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Fang Y, Ma Z, Wei D, Yu Y, Liu L, Shi Y, Gao J, Tang LC, Huang G, Song P. Engineering Sulfur-Containing Polymeric Fire-Retardant Coatings for Fire-Safe Rigid Polyurethane Foam. Macromol Rapid Commun 2024:e2400068. [PMID: 38593218 DOI: 10.1002/marc.202400068] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/31/2024] [Revised: 03/31/2024] [Indexed: 04/11/2024]
Abstract
With the advantages of lightweight and low thermal conductivity properties, polymeric foams are widely employed as thermal insulation materials for energy-saving buildings but suffer from inherent flammability. Flame-retardant coatings hold great promise for improving the fire safety of these foams without deteriorating the mechanical-physical properties of the foam. In this work, four kinds of sulfur-based flame-retardant copolymers are synthesized via a facile radical copolymerization. The sulfur-containing monomers serve as flame-retardant agents including vinyl sulfonic acid sodium (SPS), ethylene sulfonic acid sodium (VS), and sodium p-styrene sulfonate (VSS). Additionally, 2-hydroxyethyl acrylate (HEA) and 4-hydroxybutyl acrylate are employed to enable a strong interface adhesion with polymeric foams through interfacial H-bonding. By using as-synthesized waterborne flame-retardant polymeric coating with a thickness of 600 µm, the coated polyurethane foam (PUF) can achieve a desired V-0 rating during the vertical burning test with a high limiting oxygen index (LOI) of >31.5 vol%. By comparing these sulfur-containing polymeric fire-retardant coatings, poly(VS-co-HEA) coated PUF demonstrates the best interface adhesion capability and flame-retardant performance, with the lowest peak heat release rate of 166 kW m-2 and the highest LOI of 36.4 vol%. This work provides new avenues for the design and performance optimization of advanced fire-retardant polymeric coatings.
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Affiliation(s)
- Yang Fang
- College of Chemistry and Materials Engineering, Zhejiang A&F University, Hangzhou, 311300, China
| | - Zhewen Ma
- Interdisciplinary Materials Research Center, College of Materials Science and Engineering, Tongji University, Shanghai, 201804, P. R. China
| | - Dewang Wei
- College of Chemistry and Materials Engineering, Zhejiang A&F University, Hangzhou, 311300, China
| | - Youming Yu
- College of Chemistry and Materials Engineering, Zhejiang A&F University, Hangzhou, 311300, China
| | - Lei Liu
- College of Environment and Safety Engineering, Qingdao University of Science and Technology, Qingdao, 266045, China
- Centre for Further Materials, University of Southern Queensland, Springfield Central, QLD, 4300, Australia
| | - Yongqian Shi
- College of Environment and Safety Engineering, Fuzhou University, 2 Xueyuan Road, Fuzhou, 350116, China
| | - Jiefeng Gao
- School of Chemistry and Chemical Engineering, Yangzhou University, Yangzhou, 225002, China
| | - Long-Cheng Tang
- Key Laboratory of Organosilicon Chemistry and Material Technology of MoE, College of Material, Chemistry and Chemical Engineering, Hangzhou Normal University, Hangzhou, 311121, China
| | - Guobo Huang
- School of Pharmaceutical and Chemical Engineering, Taizhou University, Taizhou, 318000, China
| | - Pingan Song
- School of Agriculture and Environmental Science, Centre for Future Materials, University of Southern Queensland, Springfield, QLD, 4300, Australia
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Bennie S, Crowley JD, Wang T, Pelletier MH, Walsh WR. Pedicle screw pull-out testing in polyurethane foam blocks: Effect of block orientation and density. Proc Inst Mech Eng H 2024; 238:455-460. [PMID: 38480483 DOI: 10.1177/09544119241236873] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 04/12/2024]
Abstract
Synthetic bone models such as polyurethane (PU) foam are a well-established substitute to cadaveric bone for screw pull-out testing; however, little attention has been given to the effect of PU foam anisotropy on orthopaedic implant testing. Compressive and screw pull-out performance in three PU foam densities; 0.16 g/cm3 (PCF 10), 0.32 g/cm3 (PCF 20) and 0.64 g/cm3 (PCF 40) were performed in each of the X, Y or Z orientations. The maximum compressive force, stiffness in the linear region, maximum stress and modulus were determined for all compression tests. Pedicle screws were inserted and pulled out axially to determine maximum pull-out force, energy to failure and stiffness. One-way ANOVA and post hoc tests were used to compare outcome variables between PU foam densities and orientations, respectively. Compression tests demonstrated the maximum force was significantly different between all orientations for PCF 20 (X, Y and Z) while stiffness and maximum stress were different between X versus Y and X versus Z. Maximum pull-out force was significantly different between all orientations for PCF 10 foam. No significant differences were noted for other foam densities. There is potential for screw pull-out testing results to be significantly affected by orientation in lower density PU foams. It is recommended that a single, known orientation of the PU foam block be used for experimental testing.
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Affiliation(s)
- Stephen Bennie
- Surgical & Orthopaedic Research Laboratories (SORL), Prince of Wales Clinical School, UNSW Sydney, Sydney, NSW, Australia
| | - James Douglas Crowley
- Surgical & Orthopaedic Research Laboratories (SORL), Prince of Wales Clinical School, UNSW Sydney, Sydney, NSW, Australia
| | - Tian Wang
- Surgical & Orthopaedic Research Laboratories (SORL), Prince of Wales Clinical School, UNSW Sydney, Sydney, NSW, Australia
| | - Matthew Henry Pelletier
- Surgical & Orthopaedic Research Laboratories (SORL), Prince of Wales Clinical School, UNSW Sydney, Sydney, NSW, Australia
| | - William Robert Walsh
- Surgical & Orthopaedic Research Laboratories (SORL), Prince of Wales Clinical School, UNSW Sydney, Sydney, NSW, Australia
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Hajizadeh R, Ghiasvand F, Azimi Pirsaraei SR, Khani F, Feiz-Arefi M, Beheshti MH. Investigating the effect of hot and cold polyurethane foam on reducing whole body vibration of forklift operators. Work 2024:WOR230421. [PMID: 38517832 DOI: 10.3233/wor-230421] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 03/24/2024] Open
Abstract
BACKGROUND Vibration is one of the harmful factors for forklift drivers. The use of non- standard seats and not paying attention to how the seats are maintained can be affected by the amount of vibration transmitted to the person. OBJECTIVE This study investigates the amount of vibration transmitted from the forklift and the effect of different types of polyurethane foam in reducing the vibration transmitted from the forklift seat. METHODS This descriptive-analytical study was performed on 38 forklifts in 4 diesel models with the same weight class. The amount of vibration transmitted from forklift seats according to ISO2631 standard, taking into account the effect of various factors such as foam type (hot and cold), thickness (6-12 cm), load and year Function was measured. The amount of vibration caused by the forklift on the seat and under the seat was evaluated using ISO7096 standard. RESULTS The average total vibration of the whole body in all foams in no-load mode is more than with load. The transmission vibration of cold polyurethane foam is less than that of hot polyurethane foam. With increasing thickness, the efficiency of cold polyurethane foam increases by 12 cm and in the loaded state 40.63% and in the unloaded state 49.58% in reducing the vibration transmitted to drivers. CONCLUSION The results of this study show that cold foam has better effectiveness and efficiency than hot polyurethane foam. Also, the thicker the foam, the less vibration is transmitted to the driver.
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Affiliation(s)
- Roohalah Hajizadeh
- Department of Occupational Health Engineering, Research Center for Environmental Pollutants, School of Public Health, Qom University of Medical Sciences, Qom, Iran
| | - Fatemeh Ghiasvand
- Zanjan Student Research Center, School of Public Health, Zanjan University of Medical Sciences, Zanjan, Iran
| | - Seyed Reza Azimi Pirsaraei
- Department of Occupational Health Engineering, School of Public Health, Zanjan University of Medical Sciences, Zanjan, Iran
| | - Fouzia Khani
- Zanjan Student Research Center, School of Public Health, Zanjan University of Medical Sciences, Zanjan, Iran
| | - Maryam Feiz-Arefi
- Department of Occupational Health and Safety Engineering, Faculty of Health, Social Determinants of Health Research Center, Gonabad University of Medical Sciences, Gonabad, Iran
| | - Mohammad Hosein Beheshti
- Department of Occupational Health and Safety Engineering, Faculty of Health, Social Determinants of Health Research Center, Gonabad University of Medical Sciences, Gonabad, Iran
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Kosmela P, Sałasińska K, Kowalkowska-Zedler D, Barczewski M, Piasecki A, Saeb MR, Hejna A. Fire-Retardant Flexible Foamed Polyurethane (PU)-Based Composites: Armed and Charmed Ground Tire Rubber (GTR) Particles. Polymers (Basel) 2024; 16:656. [PMID: 38475340 DOI: 10.3390/polym16050656] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/23/2024] [Revised: 02/23/2024] [Accepted: 02/27/2024] [Indexed: 03/14/2024] Open
Abstract
Inadequate fire resistance of polymers raises questions about their advanced applications. Flexible polyurethane (PU) foams have myriad applications but inherently suffer from very high flammability. Because of the dependency of the ultimate properties (mechanical and damping performance) of PU foams on their cellular structure, reinforcement of PU with additives brings about further concerns. Though they are highly flammable and known for their environmental consequences, rubber wastes are desired from a circularity standpoint, which can also improve the mechanical properties of PU foams. In this work, melamine cyanurate (MC), melamine polyphosphate (MPP), and ammonium polyphosphate (APP) are used as well-known flame retardants (FRs) to develop highly fire-retardant ground tire rubber (GTR) particles for flexible PU foams. Analysis of the burning behavior of the resulting PU/GTR composites revealed that the armed GTR particles endowed PU with reduced flammability expressed by over 30% increase in limiting oxygen index, 50% drop in peak heat release rate, as well as reduced smoke generation. The Flame Retardancy Index (FRI) was used to classify and label PU/GTR composites such that the amount of GTR was found to be more important than that of FR type. The wide range of FRI (0.94-7.56), taking Poor to Good performance labels, was indicative of the sensitivity of flame retardancy to the hybridization of FR with GTR components, a feature of practicality. The results are promising for fire protection requirements in buildings; however, the flammability reduction was achieved at the expense of mechanical and thermal insulation performance.
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Affiliation(s)
- Paulina Kosmela
- Department of Polymer Technology, Gdańsk University of Technology, Narutowicza 11/12, 80-233 Gdańsk, Poland
| | - Kamila Sałasińska
- Faculty of Materials Science and Engineering, Warsaw University of Technology, Wołoska 141, 02-507 Warsaw, Poland
| | - Daria Kowalkowska-Zedler
- Department of Inorganic Chemistry, Gdańsk University of Technology, Narutowicza 11/12, 80-233 Gdańsk, Poland
| | - Mateusz Barczewski
- Institute of Materials Technology, Poznan University of Technology, Piotrowo 3, 61-138 Poznań, Poland
| | - Adam Piasecki
- Institute of Materials Engineering, Poznan University of Technology, Jana Pawła II 24, 60-965 Poznan, Poland
| | - Mohammad Reza Saeb
- Department of Pharmaceutical Chemistry, Medical University of Gdańsk, J. Hallera 107, 80-416 Gdańsk, Poland
| | - Aleksander Hejna
- Department of Polymer Technology, Gdańsk University of Technology, Narutowicza 11/12, 80-233 Gdańsk, Poland
- Institute of Materials Technology, Poznan University of Technology, Piotrowo 3, 61-138 Poznań, Poland
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Zhang Z, Shen G, Li R, Yuan L, Feng H, Chen X, Qiu F, Yuan G, Zhuang X. Long-Service-Life Rigid Polyurethane Foam Fillings for Spent Fuel Transportation Casks. Polymers (Basel) 2024; 16:229. [PMID: 38257028 PMCID: PMC10819990 DOI: 10.3390/polym16020229] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/20/2023] [Revised: 01/09/2024] [Accepted: 01/11/2024] [Indexed: 01/24/2024] Open
Abstract
Soft materials bearing rigid, lightweight, and vibration-dampening properties offer distinct advantages over traditional wooden and metal-based fillings for spent fuel transport casks, due to their low density, tunable structure, excellent mechanical properties, and ease of processing. In this study, a novel type of rigid polyurethane foam is prepared using a conventional polycondensation reaction between isocyanate and hydroxy groups. Moreover, the density and size of the pores in these foams are precisely controlled through simultaneous gas generation. The as-prepared polyurethane exhibits high thermal stability exceeding 185 °C. Lifetime predictions based on thermal testing indicate that these polyurethane foams could last up to over 60 years, which is double the lifetime of conventional materials of about 30 years. Due to their occlusive structure, the mechanical properties of these polymeric materials meet the design standards for spent fuel transport casks, with maximum compression and tensile stresses of 6.89 and 1.37 MPa, respectively, at a testing temperature of -40 °C. In addition, these polymers exhibit effective flame retardancy; combustion ceased within 2 s after removal of the ignition source. All in all, this study provides a simple strategy for preparing rigid polymeric foams, presenting them as promising prospects for application in spent fuel transport casks.
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Affiliation(s)
- Zhenyu Zhang
- National Engineering Research Center of Light Alloy Net Forming & State Key Laboratory of Metal Matrix Composite, Shanghai Jiao Tong University, 800 Dongchuan Road, Shanghai 200240, China;
- Shanghai Nuclear Engineering Research and Design Institute Co., Ltd., 169 Tianlin Road, Xuhui District, Shanghai 200030, China; (G.S.); (R.L.); (H.F.); (X.C.)
| | - Guangyao Shen
- Shanghai Nuclear Engineering Research and Design Institute Co., Ltd., 169 Tianlin Road, Xuhui District, Shanghai 200030, China; (G.S.); (R.L.); (H.F.); (X.C.)
| | - Rongbo Li
- Shanghai Nuclear Engineering Research and Design Institute Co., Ltd., 169 Tianlin Road, Xuhui District, Shanghai 200030, China; (G.S.); (R.L.); (H.F.); (X.C.)
| | - Lei Yuan
- The Meso-Entropy Matter Lab, State Key Laboratory of Metal Matrix Composites & Shanghai Key Laboratory of Electrical Insulation and Thermal Ageing, Frontiers Science Center for Transformative Molecules, School of Chemistry and Chemical Engineering, Shanghai Jiao Tong University, 800 Dongchuan Road, Shanghai 200240, China;
| | - Hongfu Feng
- Shanghai Nuclear Engineering Research and Design Institute Co., Ltd., 169 Tianlin Road, Xuhui District, Shanghai 200030, China; (G.S.); (R.L.); (H.F.); (X.C.)
| | - Xiuming Chen
- Shanghai Nuclear Engineering Research and Design Institute Co., Ltd., 169 Tianlin Road, Xuhui District, Shanghai 200030, China; (G.S.); (R.L.); (H.F.); (X.C.)
| | - Feng Qiu
- School of Chemical and Environmental Engineering, Shanghai Institute of Technology, 100 Haiquan Road, Shanghai 201418, China
| | - Guangyin Yuan
- National Engineering Research Center of Light Alloy Net Forming & State Key Laboratory of Metal Matrix Composite, Shanghai Jiao Tong University, 800 Dongchuan Road, Shanghai 200240, China;
| | - Xiaodong Zhuang
- The Meso-Entropy Matter Lab, State Key Laboratory of Metal Matrix Composites & Shanghai Key Laboratory of Electrical Insulation and Thermal Ageing, Frontiers Science Center for Transformative Molecules, School of Chemistry and Chemical Engineering, Shanghai Jiao Tong University, 800 Dongchuan Road, Shanghai 200240, China;
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Donadini R, Boaretti C, Scopel L, Lorenzetti A, Modesti M. Deamination of Polyols from the Glycolysis of Polyurethane. Chemistry 2024; 30:e202301919. [PMID: 37844012 DOI: 10.1002/chem.202301919] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/16/2023] [Revised: 10/13/2023] [Accepted: 10/16/2023] [Indexed: 10/18/2023]
Abstract
Methylenedianiline (MDA) is a secondary, undesired, product of the glycolysis process of polyurethane (PU) scraps due to hydrolysis and pyrolysis side reactions. As an aromatic and carcinogen amine, MDA poses different problems in handling, transporting, and labelling recycled polyols derived from glycolysis, hindering the closure of PU recycling loop. Aiming to provide a solution to this issue, in this work different deaminating agents (DAs) were investigated with the purpose of analyzing their reactivity with MDA. A first part of the study was devoted to the analysis of MDA formation as a function of reaction time and catalyst concentration (potassium acetate) during glycolysis. It was observed that the amount of MDA increases almost linearly with the extent of PU depolymerization and catalyst content. Among the DAs analyzed 2-ethylhexyl glycidyl ether (2-EHGE), and acetic anhydride (Ac2 O) showed interesting performance, which allowed MDA content to be diminished below the limit for labelling prescription in 30 minutes. PU rigid foams were, therefore, synthesized from the corresponding recycled products and characterized in terms of thermal and mechanical performance. Ac2 O-deaminated polyols led to structurally unstable foams with poor compressive strength, while 2-EHGE-deaminated products allowed the production of foams with improved mechanical performance and unaltered thermal conductivity.
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Affiliation(s)
- Riccardo Donadini
- Department of Industrial Engineering, University of Padova, via Marzolo 9, Padova, 35131, Italy
| | - Carlo Boaretti
- Department of Industrial Engineering, University of Padova, via Marzolo 9, Padova, 35131, Italy
| | - Luca Scopel
- Department of Industrial Engineering, University of Padova, via Marzolo 9, Padova, 35131, Italy
| | - Alessandra Lorenzetti
- Department of Industrial Engineering, University of Padova, via Marzolo 9, Padova, 35131, Italy
| | - Michele Modesti
- Department of Industrial Engineering, University of Padova, via Marzolo 9, Padova, 35131, Italy
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He C, Thai PK, Bertrand L, Jayarathne A, van Mourik L, Phuc DH, Banks A, Mueller JF, Wang XF. Calibration and Application of PUF Disk Passive Air Samplers To Assess Chlorinated Paraffins in Ambient Air in Australia, China, and Vietnam. Environ Sci Technol 2023; 57:21061-21070. [PMID: 37939218 DOI: 10.1021/acs.est.3c06703] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/10/2023]
Abstract
Ambient air samples were collected in Brisbane (Australia), Dalian (China), and Hanoi (Vietnam) during Mar 2013-Feb 2018 using polyurethane foam based passive air samplers. A sampling rate calibration experiment was conducted for chlorinated paraffins (CPs, i.e., short-chain, medium-chain, and long-chain CPs), where the sampling rates were 4.5 ± 0.7, 4.8 ± 0.3, and 4.8 ± 2.1 m3 day-1 for SCCPs, MCCPs, and LCCPs, respectively. The atmospheric concentration of CPs was then calculated and the medians of ∑CPs were 0.079, 1.0, and 0.89 ng m-3 in Brisbane, Dalian, and Hanoi, respectively. The concentration of CPs in Brisbane's air remained at low levels, with no significant differences observed between the city background site and the city center site, indicating limited usage and production of CPs in this city. The highest concentration of MCCPs was detected in Dalian, while the highest concentration of SCCPs was detected in Hanoi. A decrease of SCCP concentration and an increase of MCCPs' were found in Brisbane's air from 2016 to 2018, while increasing trends for both SCCPs and MCCPs were observed in Dalian. These results indicated impacts from different sources of CPs in the investigated cities.
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Affiliation(s)
- Chang He
- Guangdong-Hong Kong-Macao Joint Laboratory for Contaminants Exposure and Health, Guangdong Key Laboratory of Environmental Catalysis and Health Risk Control, Institute of Environmental Health and Pollution Control, Guangdong University of Technology, Guangzhou 510006, P. R. China
- Guangzhou Key Laboratory of Environmental Catalysis and Pollution Control, Key Laboratory for City Cluster Environmental Safety and Green Development of the Ministry of Education, School of Environmental Science and Engineering, Guangdong University of Technology, Guangzhou 510006, P. R. China
- QAEHS, Queensland Alliance for Environmental Health Sciences, The University of Queensland, 4102 Brisbane, Australia
| | - Phong K Thai
- QAEHS, Queensland Alliance for Environmental Health Sciences, The University of Queensland, 4102 Brisbane, Australia
| | - Lidwina Bertrand
- CIBICI- CONICET and Universidad Nacional de Córdoba, Facultad Ciencias Químicas, Dpto. Bioquímica Clínica, 5000 Córdoba, Argentina
| | - Ayomi Jayarathne
- QAEHS, Queensland Alliance for Environmental Health Sciences, The University of Queensland, 4102 Brisbane, Australia
| | - Louise van Mourik
- Department of Environment and Health, Vrije Universiteit, De Boelelaan 1087, 1081 HV Amsterdam, The Netherlands
| | - Dam Hoang Phuc
- Hanoi University of Science and Technology, Hanoi 10999, Viet Nam
| | - Andrew Banks
- QAEHS, Queensland Alliance for Environmental Health Sciences, The University of Queensland, 4102 Brisbane, Australia
- Racing Science Centre, Queensland Racing Integrity Commission, 4010 Brisbane, Australia
| | - Jochen F Mueller
- QAEHS, Queensland Alliance for Environmental Health Sciences, The University of Queensland, 4102 Brisbane, Australia
| | - Xianyu Fisher Wang
- QAEHS, Queensland Alliance for Environmental Health Sciences, The University of Queensland, 4102 Brisbane, Australia
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Li C, Zhang G, Yuan B. Exceptional Performance of Flame-Retardant Polyurethane Foam: The Suppression Effect on Explosion Pressure and Flame Propagation of Methane-Air Premixed Gas. Materials (Basel) 2023; 16:7602. [PMID: 38138744 PMCID: PMC10745016 DOI: 10.3390/ma16247602] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/07/2023] [Revised: 12/06/2023] [Accepted: 12/06/2023] [Indexed: 12/24/2023]
Abstract
A self-built gas explosion testing platform was used to explore the quenching effect of flame-retardant polyurethane foam on a gas explosion. The effect of the foam's filling position and length on the explosion suppression performance was explored. The results demonstrate that polyurethane foam exhibits an excellent flame-quenching performance, with a minimum of a 5 cm length of porous material being sufficient to completely quench the flame during propagation. Furthermore, the attenuation function of this porous material on the pressure wave is insignificantly affected by the change in ignition energy. Compared with the explosive state of the empty pipeline, the best suppression effect is obtained when the polyurethane foam is 20 cm in length with a filling position at 1.8 m, and the maximum explosion pressure and maximum rise rate are attenuated by 86.2% and 84.7%, respectively. This work has practical significance for the application of porous materials in explosion suppression and explosion-proof technologies in the chemical industrial processing and oil (gas) storage fields.
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Affiliation(s)
| | | | - Bihe Yuan
- School of Safety Science and Emergency Management, Wuhan University of Technology, Wuhan 430070, China; (C.L.); (G.Z.)
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Kim Y, Kong CG, Park HY, Lee KS, Sur YJ. Clinical and radiographic outcomes of negative pressure wound therapy combined with polymethylmethacrylate sealant for wound management of Gustilo type III open tibia fractures. Acta Orthop Traumatol Turc 2023; 57:366-371. [PMID: 37737582 PMCID: PMC10837575 DOI: 10.5152/j.aott.2023.22104] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/27/2022] [Accepted: 07/19/2023] [Indexed: 09/23/2023]
Abstract
OBJECTIVE This study aimed to introduce a new wound management method combining negative pressure wound therapy and polymethylmethacrylate sealant for Gustilo type III open tibia fractures and to evaluate its clinical outcomes. METHODS Among 186 patients who visited our institution for the treatment of open tibia fractures between January 2016 and December 2019, 20 male patients who sustained Gustilo type III open tibia fractures and were compelled to undergo delayed flap coverage using negative pressure wound therapy combined with polymethylmethacrylate sealant due to initial critical condition were enrolled in this study. We retrospectively investigated patients' demographics, interval between the injury and flap coverage, number of negative pressure wound therapy changes, flap survival, bone union time, and infection-induced complications. RESULTS The mean interval from injury until flap coverage was 27.8 (range, 8-63) days. Most soft-tissue defects were reconstructed using free flaps (14/20, 70%); the anterolateral thigh flap was the most frequently used flap (12/20, 60%) in this study. Among 20 flaps trans- ferred, 16 flaps (80%) survived uneventfully, 1 flap (5%) developed partial necrosis, and 3 flaps (15%) failed. The mean follow-up period was 22.7 (range, 12- 43) months. A total of 17 patients (85%) achieved tibia fracture union. The mean bone union time was 31 (range, 12-81) weeks. With regard to infection-induced complications, 3 patients (15%) developed osteomyelitis and no patient showed superficial surgical site infection. CONCLUSION Combination therapy using negative pressure wound therapy and polymethylmethacrylate sealant serves as a useful and reliable therapeutic strategy for wound management of Gustilo type III open tibia fractures, especially when delayed soft-tissue recon- struction is unavoidable. Corresponding author: Yoo Joon Sur yoojoon@catholic.ac.kr Content of this journal is licensed under a Creative Commons Attribution-NonCommercial 4.0 International License. LEVEL OF EVIDENCE Level IV, Therapeutic Study.
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Affiliation(s)
- Youngwoo Kim
- Department of Orthopedic Surgery, College of Medicine, The Catholic University of Korea, Seoul, Republic of Korea
| | - Chae Gwan Kong
- Department of Orthopedic Surgery, College of Medicine, The Catholic University of Korea, Seoul, Republic of Korea
| | - Ho Youn Park
- Department of Orthopedic Surgery, College of Medicine, The Catholic University of Korea, Seoul, Republic of Korea
| | - Kwan Soo Lee
- Department of Orthopedic Surgery, College of Medicine, The Catholic University of Korea, Seoul, Republic of Korea
| | - Yoo Joon Sur
- Department of Orthopedic Surgery, College of Medicine, The Catholic University of Korea, Seoul, Republic of Korea
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Furletov A, Apyari V, Volkov P, Torocheshnikova I, Dmitrienko S. Solid-Phase Spectrometric Determination of Organic Thiols Using a Nanocomposite Based on Silver Triangular Nanoplates and Polyurethane Foam. Sensors (Basel) 2023; 23:7994. [PMID: 37766049 PMCID: PMC10536471 DOI: 10.3390/s23187994] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/19/2023] [Revised: 09/13/2023] [Accepted: 09/19/2023] [Indexed: 09/29/2023]
Abstract
Adsorption of silver nanoparticles on polymers may affect the processes in which they participate, adjusting the analytical characteristics of methods for the quantitation of various substances. In the present study, a composite material based on silver triangular nanoplates (AgTNPs) and polyurethane foam was proposed for chemical analysis. The prospects of its application for the solid-phase/colorimetric determination of organic thiols were substantiated. It was found that aggregation of AgTNPs upon the action of thiols is manifested by a decrease in the AgTNPs' localized surface plasmon resonance band and its significant broadening. Spectral changes accompanying the process can be registered using household color-recording devices and even visually. Four thiols differing in their functional groups were tested. It was found that their limits of detection increase in the series cysteamine < 2-mercaptoethanol < cysteine = 3-mercaptopropionic acid and come to 50, 160, 500, and 500 nM, respectively. The applicability of the developed approach was demonstrated during the analysis of pharmaceuticals and food products.
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Affiliation(s)
- Aleksei Furletov
- Department of Chemistry, Lomonosov Moscow State University, 119991 Moscow, Russia
| | - Vladimir Apyari
- Department of Chemistry, Lomonosov Moscow State University, 119991 Moscow, Russia
| | - Pavel Volkov
- Scientific-Research Institute of Chemical Reagents and Special Purity Chemicals, National Research Center “Kurchatov Institute”, 107076 Moscow, Russia
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Wang Z, Wang C, Gao Y, Li Z, Shang Y, Li H. Porous Thermal Insulation Polyurethane Foam Materials. Polymers (Basel) 2023; 15:3818. [PMID: 37765672 PMCID: PMC10537539 DOI: 10.3390/polym15183818] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/18/2023] [Revised: 08/14/2023] [Accepted: 08/20/2023] [Indexed: 09/29/2023] Open
Abstract
Porous thermal insulation materials (PTIMs) are a class of materials characterized by low thermal conductivity, low bulk density and high porosity. The low thermal conductivity of the gas enclosed in their pores allows them to achieve efficient thermal insulation, and are they among the most widely used and effective materials in thermal insulation material systems. Among the PTIMs, polyurethane foam (PUF) stands out as particularly promising. Its appeal comes from its multiple beneficial features, such as low density, low thermal conductivity and superior mechanical properties. Such attributes have propelled its broad application across domains encompassing construction, heterogeneous chemical equipment, water conservation and hydropower, and the aviation and aerospace fields. First, this article outlines the structure and properties of porous thermal insulation PUF materials. Next, it explores the methods of preparing porous thermal insulation PUF materials, evaluating the associated advantages and disadvantages of each technique. Following this, the mechanical properties, thermal conductivity, thermal stability, and flame-retardant characteristics of porous thermal insulation PUF materials are characterized. Lastly, the article provides insight into the prospective development trends pertaining to porous thermal insulation PUF materials.
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Affiliation(s)
- Zhiguo Wang
- College of New Energy, Xi’an Shiyou University, Xi’an 710065, China; (Z.W.); (C.W.); (Y.S.)
| | - Chengzhu Wang
- College of New Energy, Xi’an Shiyou University, Xi’an 710065, China; (Z.W.); (C.W.); (Y.S.)
| | - Yuebin Gao
- Research Institute of Petroleum Exploration & Development, PetroChina, Beijing 100083, China;
| | - Zhao Li
- College of New Energy, Xi’an Shiyou University, Xi’an 710065, China; (Z.W.); (C.W.); (Y.S.)
| | - Yu Shang
- College of New Energy, Xi’an Shiyou University, Xi’an 710065, China; (Z.W.); (C.W.); (Y.S.)
| | - Haifu Li
- Shaanxi Haichuang Industrial Co., Ltd., Xi’an 712034, China;
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12
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Rubtsova S, Dahman Y. Biomimetic Orthopedic Footwear Advanced Insole Materials to Be Used in Medical Casts for Weight-Bearing Monitoring. Biomimetics (Basel) 2023; 8:334. [PMID: 37622939 PMCID: PMC10452612 DOI: 10.3390/biomimetics8040334] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/19/2023] [Revised: 07/12/2023] [Accepted: 07/27/2023] [Indexed: 08/26/2023] Open
Abstract
Fabrication, characterization and testing of protective biomimetic orthopedic footwear advanced insole materials are introduced. The main objective of this material is to preserve and isolate a set of sensors for the Weight-Bearing Monitoring System (WBMS) device. Twenty-one samples of renewably sourced Polyurethane Foam (PUF) composed of poly(trimethylene ether) glycol (PO3G) and unmodified castor oil (CO) were synthesized and evaluated according to predetermined criteria. Response surface methodology of Box-Behnken design was applied to study the effect of the polyols ratio, isocyanate index (II), and blowing agent ratio on the properties (hardness, density) of PUFs. Results showed that CO/PO3G/Tolyene Diisocyanate (TDI) PUFs with hardness Shore A 17-22 and density of 0.19-0.25 g/cm3 demonstrate the required characteristics and can potentially be used as a durable and functional insole material. Phase separation studies have found the presence of well-segregated structures in PUFs having polyols ratio of CO:PO3G 1:3 and low II, which further explains their extraordinary elastic properties (400% elongation). Analysis of cushioning performance of PUF signified that five samples have Cushioning Energy (CE) higher than 70 N·mm and Cushioning Factor (CF) in the range of 4-8, hence are recommended for application in WBMS due to superior weight-bearing and pressure-distributing properties. Moreover, the developed formulation undergoes anaerobic soil bacterial degradation and can be categorized as a "green" bio-based material.
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Affiliation(s)
| | - Yaser Dahman
- Department of Chemical Engineering, Toronto Metropolitan University, Toronto, ON M5B 2K3, Canada
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13
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Junaedi H, Khan T, Sebaey TA. Characteristics of Carbon-Fiber-Reinforced Polymer Face Sheet and Glass-Fiber-Reinforced Rigid Polyurethane Foam Sandwich Structures under Flexural and Compression Tests. Materials (Basel) 2023; 16:5101. [PMID: 37512375 PMCID: PMC10385354 DOI: 10.3390/ma16145101] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/28/2023] [Revised: 07/12/2023] [Accepted: 07/18/2023] [Indexed: 07/30/2023]
Abstract
Composite sandwich structures are extensively used in aircraft applications. Aircraft components are required to be robust and lightweight. Sandwich structures made of carbon-fiber-reinforced polymer as the facing sheets and milled-glass-fiber-reinforced rigid polyurethane foam with a different glass fiber content as the core structure were prepared. The influence of glass fiber content in the foam on the sandwich structure's mechanical properties was investigated. Flexural and compression tests were performed to assess the mechanical properties of the sandwich structures. Visual inspection and an optical microscope were used to observe the morphology of the polyurethane composite foams at different contents. From the flexural test, the force, facing stress and core shear stress improved with the increase in the milled fiber loading with the maximum increase at 10 wt.% loading and then a drop. Meanwhile, the compression modulus and strength increased up to 20 wt.% loadings and then dropped subsequently. The increase in the polyurethane composite foam's compression strength shifted the bending load's failure type from facing crack failure into core shear failure. The loadings range of 8-10 wt.% showed a transitional of the bending loading failure type. The density of the foams increased with the increase in milled glass fiber loading. At 10 wt.% loading, the density increased by 20%, and it increased by 47% at 30 wt.% loading. At 30 wt% loading, the optical microscope images of the foam showed wall thinning and broken walls that were responsible for the drop in the mechanical properties of the sandwich.
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Affiliation(s)
- Harri Junaedi
- Engineering Management Department, College of Engineering, Prince Sultan University, Riyadh 11586, Saudi Arabia
| | - Tabrej Khan
- Engineering Management Department, College of Engineering, Prince Sultan University, Riyadh 11586, Saudi Arabia
| | - Tamer A Sebaey
- Engineering Management Department, College of Engineering, Prince Sultan University, Riyadh 11586, Saudi Arabia
- Mechanical Design and Production Department, Faculty of Engineering, Zagazig University, Zagazig 44519, Egypt
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14
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Cho D, Oh JK. Silica Nanoparticle-Infused Omniphobic Polyurethane Foam with Bacterial Anti-Adhesion and Antifouling Properties for Hygiene Purposes. Nanomaterials (Basel) 2023; 13:2035. [PMID: 37513046 PMCID: PMC10385342 DOI: 10.3390/nano13142035] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/09/2023] [Revised: 07/05/2023] [Accepted: 07/07/2023] [Indexed: 07/30/2023]
Abstract
In this study, a method for preventing cross-infection through the surface coating treatment of polyurethane (PU) foam using functionalized silica nanoparticles was developed. Experimental results confirmed that the fabricated PU foam exhibited omniphobic characteristics, demonstrating strong resistance to both polar and nonpolar contaminants. Additionally, quantitative analysis using the pour plate method and direct counting with a scanning electron microscope determined that the treated material exhibited anti-adhesion properties against bacteria. The fabricated PU foam also demonstrated a high level of resistance to the absorption of liquids commonly found in medical facilities, including blood, 0.9% sodium chloride solution, and 50% glycerol. Mechanical durability and stability were verified through repeated compression tests and chemical leaching tests, respectively. The proposed coated PU foam is highly effective at preventing fouling from polar and nonpolar fluids as well as bacteria, making it well-suited for use in a range of fields requiring strict hygiene standards, including the medical, food, and environmental industries.
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Affiliation(s)
- Dongik Cho
- Department of Polymer Science and Engineering, Dankook University, 152 Jukjeon-ro, Suji-gu, Yongin-si 16890, Gyeonggi-do, Republic of Korea
| | - Jun Kyun Oh
- Department of Polymer Science and Engineering, Dankook University, 152 Jukjeon-ro, Suji-gu, Yongin-si 16890, Gyeonggi-do, Republic of Korea
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15
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Poirot A, Bedrici N, Walrick JC, Arrigoni M. Piezoresistive Behavior of a Conductive Polyurethane Based-Foam for Real-Time Structural Monitoring. Sensors (Basel) 2023; 23:s23115161. [PMID: 37299890 DOI: 10.3390/s23115161] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/01/2023] [Revised: 05/18/2023] [Accepted: 05/25/2023] [Indexed: 06/12/2023]
Abstract
Smart flexible materials with piezoresistive property are increasingly used in the field of sensors. When embedded in structures, they would allow for in situ structural health monitoring and damage assessment of impact loading, such as crash, bird strikes and ballistic impacts; however, this could not be achieved without a deep characterization of the relation between piezoresistivity and mechanical behavior. The aim of this paper is to study the potential use of the piezoresistivity effect of a conductive foam made of a flexible polyurethane matrix filled with activated carbon for integrated structural health monitoring (SHM) and low-energy impact detection. To do so, polyurethane foam filled with activated carbon, namely PUF-AC, is tested under quasi-static compressions and under a dynamic mechanical analyzer (DMA) with in situ measurements of its electrical resistance. A new relation is proposed for describing the evolution of the resistivity versus strain rate showing that a link exists between electrical sensitivity and viscoelasticity. In addition, a first demonstrative experiment of feasibility of an SHM application using piezoresistive foam embedded in a composite sandwich structure is realized by a low-energy impact (2 J) test.
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Affiliation(s)
- Antoine Poirot
- ESTACA, ESTACA'Lab-Laval, 53000 Laval, France
- ENSTA-Bretagne, IRDL, UMR 6027 CNRS, 2 rue François Verny, 29806 Brest, France
| | | | | | - Michel Arrigoni
- ENSTA-Bretagne, IRDL, UMR 6027 CNRS, 2 rue François Verny, 29806 Brest, France
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16
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Gu X, Wang X, Guo X, Liu S, Lou C, Liu Y. Study on Efficient Degradation of Waste PU Foam. Polymers (Basel) 2023; 15:polym15102359. [PMID: 37242933 DOI: 10.3390/polym15102359] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/21/2023] [Revised: 04/21/2023] [Accepted: 04/25/2023] [Indexed: 05/28/2023] Open
Abstract
In this paper, the high-efficiency degradation and alcoholysis recovery of waste polyurethane foam were realized using a combination of a high-efficiency alkali metal catalyst (CsOH) and two-component mixed alcoholysis agents (glycerol and butanediol) in different proportions, using recycled polyether polyol and one-step foaming to prepare regenerated thermosetting polyurethane hard foam. The foaming agent and catalyst were adjusted experimentally to prepare regenerated polyurethane foam, and a series of tests were conducted on the viscosity, GPC, hydroxyl value, infrared spectrum, foaming time, apparent density, compressive strength, and other properties of the degradation products of the regenerated thermosetting polyurethane rigid foam. The resulting data were analyzed, and the following conclusions were drawn: The optimal conditions of alcoholysis were obtained when the mass ratio of glycerol to butanediol was 3:2, the amount of cesium hydroxide was 0.08%, the reaction temperature was 170 °C, and the reaction time was 2.5 h. Regenerated polyurethane foam with an apparent density of 34.1 kg/m3 and a compressive strength of 0.301 MPa was prepared under these conditions. It had good thermal stability, complete sample pores, and a strong skeleton. At this time, these are the best reaction conditions for the alcoholysis of waste polyurethane foam, and the regenerated polyurethane foam meets various national standards.
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Affiliation(s)
- Xiaohua Gu
- School of Energy and Building Environment, Guilin University of Aerospace Technology, Guilin 541004, China
- School of Material Science and Engineering, Qiqihar University, Qiqihar 161006, China
- School of Materials Science and Engineering, Donghua University, Shanghai 200051, China
| | - Xiaoyao Wang
- School of Material Science and Engineering, Qiqihar University, Qiqihar 161006, China
| | - Xinyu Guo
- College of Chemistry and Chemical Engineering, Qiqihar University, Qiqihar 161006, China
| | - Siwen Liu
- College of Innovative Material & Energy, Hubei University, Wuhan 430062, China
| | - Chunhua Lou
- School of Energy and Building Environment, Guilin University of Aerospace Technology, Guilin 541004, China
| | - Yan Liu
- School of Energy and Building Environment, Guilin University of Aerospace Technology, Guilin 541004, China
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17
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Costantini R, Nodari L, La Nasa J, Modugno F, Bonasera L, Rago S, Zoleo A, Legnaioli S, Tomasin P. Preserving the Ephemeral: A Micro-Invasive Study on a Set of Polyurethane Scenic Objects from the 1960s and 1970s. Polymers (Basel) 2023; 15:polym15092111. [PMID: 37177259 PMCID: PMC10181275 DOI: 10.3390/polym15092111] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/27/2023] [Revised: 04/21/2023] [Accepted: 04/24/2023] [Indexed: 05/15/2023] Open
Abstract
Among the innovative materials used by 20th-century artists, polyurethane (PUR) has been shown to be highly unstable, and therefore artworks made of it are now in need of careful conservation strategies. This study presents a multi-analytical investigation of PUR foam scenic objects originally made between the 1960s and 1970s during the Italian Arte Viva movement. The main components in the foam and additives were characterized through micro attenuated total reflectance infrared spectroscopy (μ-ATR-FTIR) and pyrolysis coupled with gas chromatography and mass spectrometry (Py-GC/MS). Painted samples were further investigated through μ-FTIR and Raman spectroscopy to define binders and pigments. The use of μ-ATR-FTIR in combination with evolved gas analysis-mass spectrometry (EGA-MS) allowed the variable conditions of the artworks to be assessed and attained some insights into the chemical processes responsible for aging. At the same time, morphological changes due to the degradation phenomena were recorded through optical (OM) and scanning electron microscopy (SEM). The detailed characterization of the PUR foam and painting materials was helpful in attaining some insights into harmful environmental parameters for the artworks, thus informing preventive conservation.
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Affiliation(s)
- Rosa Costantini
- Institute of Condensed Matter Chemistry and Technologies for Energy, National Research Council, (ICMATE-CNR), Corso Stati Uniti 4, 35127 Padova, Italy
| | - Luca Nodari
- Institute of Condensed Matter Chemistry and Technologies for Energy, National Research Council, (ICMATE-CNR), Corso Stati Uniti 4, 35127 Padova, Italy
| | - Jacopo La Nasa
- Department of Chemistry and Industrial Chemistry, University of Pisa, Via Giuseppe Moruzzi 13, 56124 Pisa, Italy
| | - Francesca Modugno
- Department of Chemistry and Industrial Chemistry, University of Pisa, Via Giuseppe Moruzzi 13, 56124 Pisa, Italy
| | - Lucia Bonasera
- Department of Chemistry and Industrial Chemistry, University of Pisa, Via Giuseppe Moruzzi 13, 56124 Pisa, Italy
| | - Sara Rago
- Department of Cultural Heritage: Archaeology and History of Art, Cinema and Music, University of Padova, Piazza Capitaniato 7, 35139 Padova, Italy
| | - Alfonso Zoleo
- Department of Chemical Sciences, University of Padova, Via Marzolo 1, 35131 Padova, Italy
| | - Stefano Legnaioli
- Institute of Chemistry of Organometallic Compounds, National Research Council, (ICCOM-CNR), Via Moruzzi 1, 56124 Pisa, Italy
| | - Patrizia Tomasin
- Institute of Condensed Matter Chemistry and Technologies for Energy, National Research Council, (ICMATE-CNR), Corso Stati Uniti 4, 35127 Padova, Italy
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18
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Ponce MDV, Cina M, López C, Cerutti S. Polyurethane Foam as a Novel Material for Ochratoxin A Removal in Tea and Herbal Infusions-A Quantitative Approach. Foods 2023; 12:foods12091828. [PMID: 37174366 PMCID: PMC10178770 DOI: 10.3390/foods12091828] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/24/2023] [Revised: 04/17/2023] [Accepted: 04/26/2023] [Indexed: 05/15/2023] Open
Abstract
A novel solid-phase extraction methodology followed by UHPLC-MS/MS has been developed for Ochratoxin A (OTA) analysis in herbal infusions. For this purpose, a commercial polyurethane foam (PUF) was used as sorbent, and the experimental conditions were fully optimized. The strategy was satisfactory for reducing the matrix effect and allowed for OTA quantification in black tea and herbal infusions, with suitable recoveries and quantitation limits in agreement with those required by the maximum levels allowed by current regulations. The achieved results demonstrated the unprecedented use of polyurethane foam as an effective alternative for OTA retention and quantification in herbal infusions with the advantages of simple preparation, time saving, sustainability, and low cost for routine analysis.
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Affiliation(s)
- María Del Valle Ponce
- Instituto de Química de San Luis (INQUISAL-CONICET-UNSL), Laboratorio de Espectrometría de Masas, Facultad de Química Bioquímica y Farmacia, Universidad Nacional de San Luis, Bloque III, Ejército de los Andes 950, San Luis 5700, Argentina
- Consejo Nacional de Investigaciones Científicas y Técnicas (CONICET), Av. Rivadavia 1917, Buenos Aires 1033, Argentina
| | - Mariel Cina
- Instituto de Química de San Luis (INQUISAL-CONICET-UNSL), Laboratorio de Espectrometría de Masas, Facultad de Química Bioquímica y Farmacia, Universidad Nacional de San Luis, Bloque III, Ejército de los Andes 950, San Luis 5700, Argentina
- Consejo Nacional de Investigaciones Científicas y Técnicas (CONICET), Av. Rivadavia 1917, Buenos Aires 1033, Argentina
| | - Carlos López
- Consejo Nacional de Investigaciones Científicas y Técnicas (CONICET), Av. Rivadavia 1917, Buenos Aires 1033, Argentina
- Instituto de Investigaciones en Tecnología Química (INTEQUI-CONICET-UNSL), Facultad de Química Bioquímica y Farmacia, Universidad Nacional de San Luis, Almirante Brown 1455, San Luis 5700, Argentina
| | - Soledad Cerutti
- Instituto de Química de San Luis (INQUISAL-CONICET-UNSL), Laboratorio de Espectrometría de Masas, Facultad de Química Bioquímica y Farmacia, Universidad Nacional de San Luis, Bloque III, Ejército de los Andes 950, San Luis 5700, Argentina
- Consejo Nacional de Investigaciones Científicas y Técnicas (CONICET), Av. Rivadavia 1917, Buenos Aires 1033, Argentina
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19
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Fan Z, Zhou X. Decoding the Role of Extracellular Polymeric Substances in Enhancing Nitrogen Removal from High-Ammonia and Low-C/N Wastewater in a Sequencing Batch Packed-Bed Biofilm Reactor. Polymers (Basel) 2023; 15:polym15061510. [PMID: 36987290 PMCID: PMC10051956 DOI: 10.3390/polym15061510] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/14/2023] [Revised: 02/24/2023] [Accepted: 03/15/2023] [Indexed: 03/30/2023] Open
Abstract
Although the role of extracellular polymeric substances (EPSs) as a viscous high-molecular polymer in biological wastewater treatment has been recognized, in-depth knowledge of how EPSs affect nitrogen removal remains limited in biofilm-based reactors. Herein, we explored EPS characteristics associated with nitrogen removal from high-ammonia (NH4+-N: 300 mg/L) and low carbon-to-nitrogen ratio (C/N: 2-3) wastewater in a sequencing batch packed-bed biofilm reactor (SBPBBR) under four different operating scenarios for a total of 112 cycles. Scanning electron microscopy (SEM), atomic force microscopy (AFM), and Fourier-transform infrared (FTIR) analysis revealed that the distinct physicochemical properties, interface microstructure, and chemical composition of the bio-carrier were conducive to biofilm formation and microbial immobilization and enrichment. Under the optimal conditions (C/N: 3, dissolved oxygen: 1.3 mg/L, and cycle time: 12 h), 88.9% ammonia removal efficiency (ARE) and 81.9% nitrogen removal efficiency (NRE) could be achieved in the SBPBBR. Based on visual and SEM observations of the bio-carriers, biofilm development, biomass concentration, and microbial morphology were closely linked with nitrogen removal performance. Moreover, FTIR and three-dimensional excitation-emission matrix (3D-EEM) spectroscopy demonstrated that tightly bound EPSs (TB-EPSs) play a more important role in maintaining the stability of the biofilm. Significant shifts in the number, intensity, and position of fluorescence peaks of EPSs determined different nitrogen removal. More importantly, the high presence of tryptophan proteins and humic acids might promote advanced nitrogen removal. These findings uncover intrinsic correlations between EPSs and nitrogen removal for better controlling and optimizing biofilm reactors.
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Affiliation(s)
- Zheng Fan
- College of Environmental Science and Engineering, Taiyuan University of Technology, Taiyuan 030024, China
- Department of Biological Sciences, National University of Singapore, Singapore 117543, Singapore
| | - Xin Zhou
- College of Environmental Science and Engineering, Taiyuan University of Technology, Taiyuan 030024, China
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20
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Xiong Q, Qu J, Zhao R, Chen Y, Li Y, Xu W, Pan B, Jin P, Zheng Z. Fabrication of a novel polyurethane foam-alginate-zeolite hydrogel and subsequent KSND bacteria encapsulation: evidence of accelerated biofilm colonization and enhanced nitrogen removal efficiency. Lett Appl Microbiol 2023; 76:7059211. [PMID: 36849163 DOI: 10.1093/lambio/ovac054] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/29/2022] [Revised: 10/15/2022] [Accepted: 02/25/2023] [Indexed: 03/01/2023]
Abstract
Biofilms are used widely to remove nitrogen from wastewater; however, most biofilm carriers (i.e. polyurethane foam, PUF) are hydrophobic organic materials with millimetre-scale apertures, ineffective attachment, and unstable colonization of microorganisms. To address these limitations, hydrophilic sodium alginate (SA) mixed with zeolite powder (Zeo) was cross-linked in PUF to form a micro-scale hydrogel (PAS) with a well-organized and reticular cellular structure. Scanning electron microscopy revealed that immobilized cells were entrapped in the interior of hydrogel filaments and rapidly formed a stable biofilm on the surface. The biofilm generated was 10.3-fold greater than the film developed on PUF. Kinetics and isotherm studies revealed that the as-developed carrier, because of the presence of Zeo, effectively improved the adsorption of NH4+-N by 53%. The PAS carrier achieved total nitrogen removal in excess of 86% for low carbon-to-nitrogen ratio wastewater treated for 30 d, indicating that this novel modification-encapsulation technology has potential for wastewater treatment.
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Affiliation(s)
- Qinyi Xiong
- School of Environmental and Resource, Zhejiang A & F University, Hangzhou 311300, China
| | - Jin Qu
- School of Environmental and Resource, Zhejiang A & F University, Hangzhou 311300, China
| | - Ruojin Zhao
- Zhejiang Shuangliang Sunda Environment Co., Ltd., Hangzhou 310000, China
| | - Yinyan Chen
- Zhejiang Shuangliang Sunda Environment Co., Ltd., Hangzhou 310000, China
| | - Yiyi Li
- Zhejiang Shuangliang Sunda Environment Co., Ltd., Hangzhou 310000, China
| | - Weiping Xu
- Zhejiang Shuangliang Sunda Environment Co., Ltd., Hangzhou 310000, China
| | - Biwen Pan
- Zhejiang Shuangliang Sunda Environment Co., Ltd., Hangzhou 310000, China
| | - Peng Jin
- College of Food and Health, Zhejiang A & F University, Hangzhou 311300, China
| | - Zhanwang Zheng
- School of Environmental and Resource, Zhejiang A & F University, Hangzhou 311300, China.,Zhejiang Shuangliang Sunda Environment Co., Ltd., Hangzhou 310000, China
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21
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Tan JLT, Shimabukuro M, Kishida R, Ishikawa K. Fabrication and histological evaluation of ant-nest type porous carbonate apatite artificial bone using polyurethane foam as a porogen. J Biomed Mater Res B Appl Biomater 2023; 111:560-567. [PMID: 36205010 DOI: 10.1002/jbm.b.35173] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/22/2022] [Revised: 09/05/2022] [Accepted: 09/19/2022] [Indexed: 01/25/2023]
Abstract
The composition of carbonate apatite (CO3 Ap) aids bone regeneration. Other features, such as porosity and pore interconnectivity of artificial bone, also govern bone regeneration. In general, a trade-off exists between the porosity and mechanical strength of artificial bone. Therefore, this suggests that the interconnected pores in the ant-nest-type porous (ANP) structure of artificial bone accelerate bone regeneration by minimizing the sacrifice of mechanical strength. The unique structure of polyurethane foam has the potential to endow CO3 Ap with an ANP structure without forming excess pores. This study investigated the efficacy of polyurethane foam as a porogen in providing ANP structure to CO3 Ap artificial bone. The polyurethane foam was completely decomposed by sintering and the resulting CO3 Ap displayed ANP structure with a compressive strength of approximately 15 MPa. Furthermore, in vivo experiments revealed that the migration of cells and tissues into the interior of CO3 Ap through the interconnected pores accelerated bone regeneration in the ANP-structured CO3 Ap. Thus, this indicates that using polyurethane foam as a porogen endows the CO3 Ap artificial bone with an ANP structure that accelerates bone regeneration.
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Affiliation(s)
| | - Masaya Shimabukuro
- Faculty of Dental Science, Kyushu University, Fukuoka, Japan.,Institute of Biomaterials and Bioengineering, Tokyo Medical and Dental University, Tokyo, Japan
| | - Ryo Kishida
- Faculty of Dental Science, Kyushu University, Fukuoka, Japan
| | - Kunio Ishikawa
- Faculty of Dental Science, Kyushu University, Fukuoka, Japan
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22
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Vieira FR, Gama NV, Evtuguin DV, Amorim CO, Amaral VS, Pinto PCOR, Barros-Timmons A. Bio-Based Polyurethane Foams from Kraft Lignin with Improved Fire Resistance. Polymers (Basel) 2023; 15:polym15051074. [PMID: 36904315 PMCID: PMC10005662 DOI: 10.3390/polym15051074] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/30/2022] [Revised: 02/08/2023] [Accepted: 02/13/2023] [Indexed: 02/24/2023] Open
Abstract
Rigid polyurethane foams (RPUFs) were synthesized using exclusively lignin-based polyol (LBP) obtained via the oxyalkylation of kraft lignin with propylene carbonate (PC). Using the design of experiments methodology combined with statistical analysis, the formulations were optimized to obtain a bio-based RPUF with low thermal conductivity and low apparent density to be used as a lightweight insulating material. The thermo-mechanical properties of the ensuing foams were compared with those of a commercial RPUF and a RPUF (RPUF-conv) produced using a conventional polyol. The bio-based RPUF obtained using the optimized formulation exhibited low thermal conductivity (0.0289 W/m·K), low density (33.2 kg/m3), and reasonable cell morphology. Although the bio-based RPUF has slightly lower thermo-oxidative stability and mechanical properties than RPUF-conv, it is still suitable for thermal insulation applications. In addition, the fire resistance of this bio-based foam has been improved, with its average heat release rate (HRR) reduced by 18.5% and its burn time extended by 25% compared to RPUF-conv. Overall, this bio-based RPUF has shown potential to replace petroleum-based RPUF as an insulating material. This is the first report regarding the use of 100% unpurified LBP obtained via the oxyalkylation of LignoBoost kraft lignin in the production of RPUFs.
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Affiliation(s)
- Fernanda R. Vieira
- CICECO-Institute of Materials and Department of Chemistry, Campus de Santiago, University of Aveiro, 3810-193 Aveiro, Portugal
- Correspondence: (F.R.V.); (A.B.-T.)
| | - Nuno V. Gama
- CICECO-Institute of Materials and Department of Chemistry, Campus de Santiago, University of Aveiro, 3810-193 Aveiro, Portugal
| | - Dmitry V. Evtuguin
- CICECO-Institute of Materials and Department of Chemistry, Campus de Santiago, University of Aveiro, 3810-193 Aveiro, Portugal
| | - Carlos O. Amorim
- CICECO-Institute of Materials and Department of Physics, University of Aveiro, 3810-193 Aveiro, Portugal
| | - Vitor S. Amaral
- CICECO-Institute of Materials and Department of Physics, University of Aveiro, 3810-193 Aveiro, Portugal
| | - Paula C. O. R. Pinto
- RAIZ, Forest and Paper Research Institute, Quinta de S. Francisco, 3801-501 Aveiro, Portugal
| | - Ana Barros-Timmons
- CICECO-Institute of Materials and Department of Chemistry, Campus de Santiago, University of Aveiro, 3810-193 Aveiro, Portugal
- Correspondence: (F.R.V.); (A.B.-T.)
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Węgrzyk G, Grzęda D, Ryszkowska J. The Effect of Mixing Pressure in a High-Pressure Machine on Morphological and Physical Properties of Free-Rising Rigid Polyurethane Foams-A Case Study. Materials (Basel) 2023; 16:857. [PMID: 36676592 PMCID: PMC9866240 DOI: 10.3390/ma16020857] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 12/13/2022] [Revised: 01/10/2023] [Accepted: 01/13/2023] [Indexed: 06/17/2023]
Abstract
This article presents the results of testing foam blocks made with a high-pressure foaming machine under industrial conditions. Foam blocks were made at pressures in the range of 110-170 bar with substrate temperatures allowed by machine suppliers. The foaming process parameters of each block were evaluated. The structure of the foams in the outer and central parts of the blocks was characterized using FTIR spectroscopic analysis and microscopic observations using SEM. The changes in apparent density, strength properties and brittleness of the foams were evaluated. The properties of the blocks made at different mixing pressures varied depending on the pressure at which the substrates were mixed and the location in the block. The biggest differences that were observed were the friability of the foams taken from different locations in the blocks by up to about 30%; the apparent density differed by about 8% and the compressive strength by about 5%.
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24
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Fan J, Li P, Guo W, Zhao X, Su C, Xu X. Experimental Investigation on the Low-Velocity Impact Response of Tandem Nomex Honeycomb Sandwich Panels. Polymers (Basel) 2023; 15:456. [PMID: 36679337 DOI: 10.3390/polym15020456] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/11/2022] [Revised: 01/12/2023] [Accepted: 01/13/2023] [Indexed: 01/19/2023] Open
Abstract
Sandwich panels are often subjected to unpredictable impacts and crashes in applications. The core type and impactor shape affect their impact response. This paper investigates the responses of five tandem Nomex honeycomb sandwich panels with different core-types under low-velocity-impact conditions with flat and hemispherical impactors. From the force response and impact displacement, gradient-tandem and foam-filled structures can improve the impact resistance of sandwich panels. Compared with the single-layer sandwich panel, the first peak of contact force of the foam-gradient-filled tandem honeycomb sandwich panels increased by 34.84%, and maximum impact displacement reduced by 50.98%. The resistance of gradient-tandem Nomex honeycomb sandwich panels under low-velocity impact outperformed uniform-tandem structures. Foam-filled structures change the impact responses of the tandem sandwich panels. Impact damage with a flat impactor was more severe than the hemispherical impactor. The experimental results are helpful in the design of tandem Nomex honeycomb sandwich panels.
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Kowalczyk Ł, Korol J, Chmielnicki B, Laska A, Chuchala D, Hejna A. One More Step towards a Circular Economy for Thermal Insulation Materials-Development of Composites Highly Filled with Waste Polyurethane (PU) Foam for Potential Use in the Building Industry. Materials (Basel) 2023; 16:782. [PMID: 36676519 PMCID: PMC9864609 DOI: 10.3390/ma16020782] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 12/19/2022] [Revised: 01/04/2023] [Accepted: 01/11/2023] [Indexed: 06/17/2023]
Abstract
The rapid development of the building sector has created increased demand for novel materials and technologies, while on the other hand resulting in the generation of a severe amount of waste materials. Among these are polyurethane (PU) foams, which are commonly applied as thermal insulation materials. Their management is a serious industrial problem, due to, for example, their complex chemical composition. Although some chemical and thermochemical methods of PU foam recycling are known, their broader use is limited due to requirements related to the complexity and safety of their installation, thus implicating high costs. Therefore, material recycling poses a promising alternative. The incorporation of waste PU foams as fillers for polymer composites could make it possible to take advantage of their structure and performance. Herein, polypropylene-based composites that were highly filled with waste PU foam and modified using foaming agents were prepared and analyzed. Depending on the foam loading and the foaming agent applied, the apparent density of material was reduced by as much as 68%. The efficient development of a porous structure, confirmed by scanning electron microscopy and high-resolution computed micro-tomography, enabled a 64% decrease in the thermal conductivity coefficient. The foaming of the structure affected the mechanical performance of composites, resulting in a deterioration of their tensile and compressive performance. Therefore, developing samples of the analyzed composites with the desired performance would require identifying the proper balance between mechanical strength and economic, as well as ecological (share of waste material in composite, apparent density of material), considerations.
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Affiliation(s)
- Łukasz Kowalczyk
- Central Mining Institute, Department of Material Engineering, Pl. Gwarkow 1, 40-166 Katowice, Poland
| | - Jerzy Korol
- Central Mining Institute, Department of Material Engineering, Pl. Gwarkow 1, 40-166 Katowice, Poland
| | - Błażej Chmielnicki
- Łukasiewicz Research Network–Institute of Engineering of Polymer Materials and Dyes, Center for Paints and Plastics, ul. Chorzowska 50A, 44-100 Gliwice, Poland
| | - Aleksandra Laska
- Faculty of Mechanical Engineering and Ship Technology and EkoTech Center, Gdańsk University of Technology, 80-233 Gdańsk, Poland
| | - Daniel Chuchala
- Faculty of Mechanical Engineering and Ship Technology and EkoTech Center, Gdańsk University of Technology, 80-233 Gdańsk, Poland
| | - Aleksander Hejna
- Institute of Materials Technology, Poznan University of Technology, Piotrowo 3, 60-965 Poznań, Poland
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Olszewski A, Kosmela P, Piasecki A, Barczewski M, Hejna A. The Impact of Isocyanate Index and Filler Functionalities on the Performance of Flexible Foamed Polyurethane/Ground Tire Rubber Composites. Polymers (Basel) 2022; 14. [PMID: 36559925 DOI: 10.3390/polym14245558] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/22/2022] [Revised: 12/13/2022] [Accepted: 12/16/2022] [Indexed: 12/23/2022] Open
Abstract
The structure and performance of polyurethane (PU) foams are strongly driven by the stoichiometry of the polyaddition reaction, quantitatively described by the isocyanate index. It determines the balance between isocyanate and hydroxyl groups in the reacting system and is affected by the introduction of additional functionalities originated, e.g., from applied fillers. Nevertheless, this issue is hardly taken into account in research works. Herein, the structure and performance of PU/ground tire rubber (GTR) composites differing in their isocyanate index (from 0.8 to 1.2) and prepared with and without considering the GTR functionalities in formulation development were investigated. Incorporating GTR into the PU matrix led to a reduction in average cell diameter (from 2 to 30% depending on the isocyanate index) compared to unfilled foams. However, formulation adjustments did not show a significant impact on cellular structure. The only decrease in open cell content was noted, from 10% for the 0.9 index to 40% for 1.2. Such changes were related to the increasing strength of the PU cellular structure able to maintain inside the increasing amount of carbon dioxide. On the other hand, considering hydroxyl values of GTR noticeably affected the thermomechanical performance of composites. The shift of glass transition temperature (Tg), even by 10 °C for 1.2 isocyanate index, enhanced the performance of materials, which was expressed in an 8-62% drop in the composite performance factor, pointing to the enhanced reinforcing effect resulting from filler incorporation. The stiffening of foams, related to the variations in PU segmental structure, also caused minor changes in the course of thermal degradation of PU/GTR composites due to the inferior thermal stability of hard segments. The obtained results provide important insights into the development of formulations of PU composites filled with materials containing reactive functional groups able to disrupt the stoichiometric balance of the polyaddition reaction.
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Acosta A, Aramburu AB, Beltrame R, Gatto DA, Amico S, Labidi J, Delucis RDA. Wood Flour Modified by Poly(furfuryl alcohol) as a Filler in Rigid Polyurethane Foams: Effect on Water Uptake. Polymers (Basel) 2022; 14:polym14245510. [PMID: 36559877 PMCID: PMC9784639 DOI: 10.3390/polym14245510] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/09/2022] [Revised: 11/30/2022] [Accepted: 12/13/2022] [Indexed: 12/23/2022] Open
Abstract
The use of lignocellulosic fillers in rigid polyurethane foams (RPUFs) has been receiving great attention due to their good mechanical and insulation properties and the high sustainable appeal of the obtained cellular polymers, although high water uptakes are found in most of these systems. To mitigate this detrimental effect, RPUFs filled with wood flour (2.5% wt) were fabricated with the addition of furfuryl alcohol (FA) to create a polymer grafted with the wood filler. Two concentrations of FA (10 wt% and 15 wt%) were investigated in relation to the wood flour, and the RPUFs were characterized for cell morphology, density, compressive properties, thermal stability, and water uptake. The introduction of wood flour as a filler decreased the cell size and increased the anisotropy index of the RPUFs and, in addition to that, the FA grafting increased these effects even more. In general, there were no significant changes in both mechanical and thermal properties ascribed to the incorporation of the fillers. On the other hand, a reduction of up to 200% in water uptake was ascribed to the FA-treated fillers.
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Affiliation(s)
- Andrey Acosta
- Post-Graduate Program in Mining, Metallurgical and Materials Engineering, Federal University of Rio Grande do Sul, Porto Alegre 91509-900, Brazil
- Correspondence: (A.A.); (J.L.)
| | - Arthur B. Aramburu
- Post-Graduate Program in Mining, Metallurgical and Materials Engineering, Federal University of Rio Grande do Sul, Porto Alegre 91509-900, Brazil
| | - Rafael Beltrame
- Post-Graduate Program in Materials Science and Engineering, Federal University of Pelotas, Pelotas 96010-610, Brazil
- Post-Graduate Program in Environmental Sciences, Federal University of Pelotas, Pelotas 96010-610, Brazil
| | - Darci A. Gatto
- Post-Graduate Program in Materials Science and Engineering, Federal University of Pelotas, Pelotas 96010-610, Brazil
- Post-Graduate Program in Environmental Sciences, Federal University of Pelotas, Pelotas 96010-610, Brazil
| | - Sandro Amico
- Post-Graduate Program in Mining, Metallurgical and Materials Engineering, Federal University of Rio Grande do Sul, Porto Alegre 91509-900, Brazil
| | - Jalel Labidi
- Environmental and Chemical Engineering Department, University of the Basque Country, Plaza de Europa 1, 20018 San Sebastián, Spain
- Correspondence: (A.A.); (J.L.)
| | - Rafael de Avila Delucis
- Post-Graduate Program in Materials Science and Engineering, Federal University of Pelotas, Pelotas 96010-610, Brazil
- Post-Graduate Program in Environmental Sciences, Federal University of Pelotas, Pelotas 96010-610, Brazil
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28
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Hasanzadeh R, Mojaver P, Khalilarya S, Azdast T, Chitsaz A, Mojaver M. Polyurethane Foam Waste Upcycling into an Efficient and Low Pollutant Gasification Syngas. Polymers (Basel) 2022; 14:polym14224938. [PMID: 36433065 PMCID: PMC9694370 DOI: 10.3390/polym14224938] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/14/2022] [Revised: 11/07/2022] [Accepted: 11/11/2022] [Indexed: 11/18/2022] Open
Abstract
Waste treatment has attracted much attention and, in this regard, gasification processes offer an efficient thermochemical technique that can produce a syngas rich in hydrogen. This technique has been well developed for solid waste and biomass while investigations on gasification of polymeric foam are rare. Therefore, this study explores the treatment of polyurethane foam waste with different gasifying agents, based on thermodynamic modeling. The polymeric foam gasification was developed using the best model for estimating higher heating value (gross calorific value). As the results indicated, models based on both ultimate and proximate analyses had better performance in predicting higher heating value. As one of the main objectives and novelties, the steam and air gasification performance of flexible and rigid polyurethane foam wastes was investigated and compared from efficiency and CO2 emission viewpoints. Polyurethane foam gasification by steam resulted in higher hydrogen efficiency, led to lower energy efficiency and produced lower CO2 emissions compared to gasification by air. A hydrogen efficiency of 41.4% was obtained for gasification of waste flexible polyurethane foam by steam. An energy efficiency of 76.6% and CO2 emission of 7.43 g per mole of feedstock were attained for waste flexible polyurethane foam gasified by air.
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29
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Uricchio A, Lasalandra T, Tamborra ERG, Caputo G, Mota RP, Fanelli F. Atmospheric Pressure Plasma-Treated Polyurethane Foam as Reusable Absorbent for Removal of Oils and Organic Solvents from Water. Materials (Basel) 2022; 15:7948. [PMID: 36431434 PMCID: PMC9693071 DOI: 10.3390/ma15227948] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 10/09/2022] [Revised: 11/04/2022] [Accepted: 11/08/2022] [Indexed: 06/16/2023]
Abstract
This paper reports the optimization of a two-step atmospheric pressure plasma process to modify the surface properties of a polyurethane (PU) foam and, specifically, to prepare a superhydrophobic/superoleophilic absorbent for the removal of oils and nonpolar organic solvents from water. In particular, in the first step, an oxygen-containing dielectric barrier discharge (DBD) is used to induce the etching/nanotexturing of the foam surfaces; in the second step, an ethylene-containing DBD enables uniform overcoating with a low-surface-energy hydrocarbon polymer film. The combination of surface nanostructuring and low surface energy ultimately leads to simultaneous superhydrophobic and superoleophilic wetting properties. X-ray photoelectron spectroscopy, scanning electron microscopy and water contact angle measurements are used for the characterization of the samples. The plasma-treated PU foam selectively absorbs various kinds of hydrocarbon-based liquids (i.e., hydrocarbon solvents, mineral oils, motor oil, diesel and gasoline) up to 23 times its own weight, while it completely repels water. These absorption performances are maintained even after 50 absorption/desorption cycles and after immersion in hot water as well as acidic, basic and salt aqueous solutions. The plasma-treated foam can remove mineral oil while floating on the surface of mineral oil/water mixtures with a separation efficiency greater than 99%, which remains unaltered after 20 separation cycles.
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Affiliation(s)
- Antonella Uricchio
- Department of Chemistry, University of Bari “Aldo Moro”, Via Orabona 4, 70125 Bari, Italy
| | - Teresa Lasalandra
- Department of Chemistry, University of Bari “Aldo Moro”, Via Orabona 4, 70125 Bari, Italy
| | - Eliana R. G. Tamborra
- Department of Chemistry, University of Bari “Aldo Moro”, Via Orabona 4, 70125 Bari, Italy
| | - Gianvito Caputo
- Nanochemistry Department, Istituto Italiano di Tecnologia, Via Morego 30, 16163 Genoa, Italy
| | - Rogério P. Mota
- Department of Physics, Faculty of Engineering and Science, São Paulo State University (UNESP), 12516-410 Guaratinguetá, SP, Brazil
| | - Fiorenza Fanelli
- Institute of Nanotechnology (NANOTEC), National Research Council (CNR), c/o Department of Chemistry, University of Bari “Aldo Moro”, Via Orabona 4, 70125 Bari, Italy
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30
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Malewska E, Polaczek K, Kurańska M. Impact of Various Catalysts on Transesterification of Used Cooking Oil and Foaming Processes of Polyurethane Systems. Materials (Basel) 2022; 15:7807. [PMID: 36363400 PMCID: PMC9657215 DOI: 10.3390/ma15217807] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 10/14/2022] [Revised: 10/31/2022] [Accepted: 11/02/2022] [Indexed: 06/16/2023]
Abstract
The search for new sources of raw materials that can be used in the synthesis of polyurethanes and other polymer groups is extremely important. Currently, according to the principles of green chemistry and a circular economy, waste materials with a high reuse potential are being sought. This article presents a way of obtaining used-cooking-oil-based compounds capable of participating in the reaction of polyurethane creation. The transesterification reaction can be carried out using a variety of homo- and heterogeneous acid or base catalysts. Here, we looked at the impact of selected catalysts on the course of transesterification reactions, the composition of the post-reaction mixture and the possibility of using the products in polyurethane foam synthesis. The raw materials and the products were analyzed by means of gel permeation chromatography, FTIR spectroscopy and 1H NMR. The polyurethane foam formation process was analyzed using a FOAMAT® apparatus.
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31
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Wang C, Du L, Xing X, Feng D, Yang D. Lightweight Porous Polyurethane Foam Integrated with Graphene Oxide for Flexible and High-Concentration Hydrogen Sensing. ACS Sens 2022; 7:2420-2428. [PMID: 35854426 DOI: 10.1021/acssensors.2c01129] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Abstract
Reliable detection of high-concentration hydrogen (H2) leakage in sharp-vibration environments is highly desired such as in the application of space rockets. As hydrogen has to be detected simultaneously in a wide concentration range and at high concentrations (e.g., 100 v/v%) with outstanding linearity in response/concentration, lightweight features, and excellent tolerance against saturation and vibration, it remains challenging. Here, a flexible and high-concentration H2 sensing has been developed through "dipping-drying" a three-dimensional (3D) porous polyurethane (PU) foam integrated with graphene oxide (GO-PU). Multilayered honeycomb-structured graphene oxide appears to be tightly adhered to faveolate PU. Benefiting from the numerous adsorption sites of the "dual honeycomb" structure and abundant surface functional groups of GO, the GO-PU foam exhibits distinguished response and linearity toward 2-100 v/v% H2 and shows excellent lightweight, tailorability, and flexibility. Remarkably, the foam possesses outstanding sensing stability against 0-180° bending and low 0-20% straining, along with outstanding H2 sensing performance even after being pressed by a weight of 200 g, immersed in water, and frozen in a refrigerator at -10.8 °C. Practically, the GO-PU foam has potential for high-concentration H2 leakage detection, and our synthetic strategy may provide a way to avoid adsorbing saturation in other flexible gas sensing.
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Affiliation(s)
- Chen Wang
- Tianjin Key Laboratory of Optoelectronic Sensor and Sensing Network Technology, Engineering Research Center of Thin Film Optoelectronics Technology, Ministry of Education and Department of Electronics, College of Electronic Information and Optical Engineering, Nankai University, Tianjin 300350, P. R. China
| | - Lingling Du
- Tianjin Key Laboratory of Optoelectronic Sensor and Sensing Network Technology, Engineering Research Center of Thin Film Optoelectronics Technology, Ministry of Education and Department of Electronics, College of Electronic Information and Optical Engineering, Nankai University, Tianjin 300350, P. R. China
| | - Xiaxia Xing
- Tianjin Key Laboratory of Optoelectronic Sensor and Sensing Network Technology, Engineering Research Center of Thin Film Optoelectronics Technology, Ministry of Education and Department of Electronics, College of Electronic Information and Optical Engineering, Nankai University, Tianjin 300350, P. R. China
| | - Dongliang Feng
- Tianjin Key Laboratory of Optoelectronic Sensor and Sensing Network Technology, Engineering Research Center of Thin Film Optoelectronics Technology, Ministry of Education and Department of Electronics, College of Electronic Information and Optical Engineering, Nankai University, Tianjin 300350, P. R. China
| | - Dachi Yang
- Tianjin Key Laboratory of Optoelectronic Sensor and Sensing Network Technology, Engineering Research Center of Thin Film Optoelectronics Technology, Ministry of Education and Department of Electronics, College of Electronic Information and Optical Engineering, Nankai University, Tianjin 300350, P. R. China
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32
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Żukowska W, Kosmela P, Wojtasz P, Szczepański M, Piasecki A, Barczewski R, Barczewski M, Hejna A. Comprehensive Enhancement of Prepolymer-Based Flexible Polyurethane Foams' Performance by Introduction of Cost-Effective Waste-Based Ground Tire Rubber Particles. Materials (Basel) 2022; 15:ma15165728. [PMID: 36013863 PMCID: PMC9412428 DOI: 10.3390/ma15165728] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/22/2022] [Revised: 08/13/2022] [Accepted: 08/18/2022] [Indexed: 05/11/2023]
Abstract
Material innovations in polyurethane (PU) foams should ideally combine performance enhancement, environmental impact limitation, and cost reduction. These goals can be achieved by applying recycled or waste-based materials without broader industrial applications, implicating their low price. Herein, from 5 to 20 parts by weight of ground tire rubber (GTR) particles originated from the recycling of postconsumer car tires were incorporated into a flexible foamed PU matrix as a cost-effective waste-based filler. A two-step prepolymer method of foams manufacturing was applied to maximize the potential of applied formulation changes. The impact of the GTR content on the foams' processing, chemical, and cellular structure, as well as static and dynamic mechanical properties, thermal stability, sound suppression ability, and thermal insulation performance, was investigated. The introduction of GTR caused a beneficial reduction in the average cell diameter, from 263.1 µm to 144.8-188.5 µm, implicating a 1.0-4.3% decrease in the thermal conductivity coefficient. Moreover, due to the excellent mechanical performance of the car tires-the primary application of GTR-the tensile performance of the foams was enhanced despite the disruption of the cellular structure resulting from the competitiveness between the hydroxyl groups of the applied polyols and on the surface of the GTR particles. The tensile strength and elongation at break were increased by 10 and 8% for 20 parts by weight GTR addition. Generally, the presented work indicates that GTR can be efficiently applied as a filler for flexible PU foams, which could simultaneously enhance their performance, reduce costs, and limit environmental impacts due to the application of waste-based material.
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Affiliation(s)
- Wiktoria Żukowska
- Department of Polymer Technology, Gdańsk University of Technology, Narutowicza 11/12, 80-233 Gdańsk, Poland
| | - Paulina Kosmela
- Department of Polymer Technology, Gdańsk University of Technology, Narutowicza 11/12, 80-233 Gdańsk, Poland
| | - Paweł Wojtasz
- Department of Polymer Technology, Gdańsk University of Technology, Narutowicza 11/12, 80-233 Gdańsk, Poland
| | - Mariusz Szczepański
- Department of Polymer Technology, Gdańsk University of Technology, Narutowicza 11/12, 80-233 Gdańsk, Poland
| | - Adam Piasecki
- Institute of Materials Engineering, Poznan University of Technology, Jana Pawła II 24, 60-965 Poznan, Poland
| | - Roman Barczewski
- Institute of Applied Mechanics, Poznan University of Technology, Jana Pawła II 24, 60-965 Poznan, Poland
| | - Mateusz Barczewski
- Institute of Materials Technology, Poznan University of Technology, Piotrowo 3, 61-138 Poznan, Poland
| | - Aleksander Hejna
- Department of Polymer Technology, Gdańsk University of Technology, Narutowicza 11/12, 80-233 Gdańsk, Poland
- Correspondence:
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Oraby H, Tantawy HR, Correa-Duarte MA, Darwish M, Elsaidy A, Naeem I, Senna MH. Tuning Electro-Magnetic Interference Shielding Efficiency of Customized Polyurethane Composite Foams Taking Advantage of rGO/Fe 3O 4 Hybrid Nanocomposites. Nanomaterials (Basel) 2022; 12:2805. [PMID: 36014670 PMCID: PMC9415845 DOI: 10.3390/nano12162805] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 07/14/2022] [Revised: 07/30/2022] [Accepted: 08/09/2022] [Indexed: 06/15/2023]
Abstract
Electromagnetic interference (EMI) has been recognized as a new sort of pollution and can be considered as the direct interference of electromagnetic waves among electronic equipment that frequently affects their typical efficiency. As a result, shielding the electronics from this interfering radiation has been addressed as critical issue of great interest. In this study, different hybrid nanocomposites consisting of magnetite nanoparticles (Fe3O4) and reduced graphene oxide (rGO) as (conductive/magnetic) fillers, taking into account different rGO mass ratios, were synthesized and characterized by XRD, Raman spectroscopy, TEM and their magnetic properties were assessed via VSM. The acquired fillers were encapsulated in the polyurethane foam matrix with different loading percentages (wt%) to evaluate their role in EMI shielding. Moreover, their structure, morphology, and thermal stability were investigated by SEM, FTIR, and TGA, respectively. In addition, the impact of filler loading on their final mechanical properties was determined. The obtained results revealed that the Fe3O4@rGO composites displayed superparamagnetic behavior and acceptable electrical conductivity value. The performance assessment of the conducting Fe3O4@rGO/PU composite foams in EMI shielding efficiency (SE) was investigated at the X-band (8-12) GHz, and interestingly, an optimized value of SE -33 dBw was achieved with Fe3O4@rGO at a 80:20 wt% ratio and 35 wt% filler loading in the final effective PU matrix. Thus, this study sheds light on a novel optimization strategy for electromagnetic shielding, taking into account conducting new materials with variable filler loading, composition ratio, and mechanical properties in such a way as to open the door for achieving a remarkable SE.
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Affiliation(s)
- Hussein Oraby
- Department of Chemical Engineering, Military Technical College, Cairo 1111, Egypt
| | - Hesham Ramzy Tantawy
- Department of Chemical Engineering, Military Technical College, Cairo 1111, Egypt
| | | | - Mohammad Darwish
- Department of Radar, Military Technical College, Cairo 4393010, Egypt
| | - Amir Elsaidy
- Department of Chemical Engineering, Military Technical College, Cairo 1111, Egypt
| | - Ibrahim Naeem
- Department of Chemical Engineering, Military Technical College, Cairo 1111, Egypt
| | - Magdy H. Senna
- Radiation Chemistry Department, National Center for Radiation Research and Technology, Atomic Energy Authority, Cairo 11762, Egypt
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Sayles C, Finnegan N, Pike T, Spence MW. Toluene diisocyanate occupational exposure data in the polyurethane industry (2005-2020): A descriptive summary from an industrial hygiene perspective. Toxicol Ind Health 2022; 38:606-621. [PMID: 35929225 DOI: 10.1177/07482337221112225] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
Abstract
This article provides an overview of toluene diisocyanate (TDI) workplace air concentration data. Data were collected between 2005-2020 in workplaces across the United States, Canada, and the European Union by a number of different organizations, primarily using the sampling procedures published in OSHA Methods 42 and 5002. The data were then collated and organized by the International Isocyanate Institute. Air samples were collected from several market segments, with a large portion of the data (87%) from the flexible foam industry. The air samples (2534 in total) were categorized into "area" or "personal," and the personal samples were subcategorized into "task," "short term," and "long term." Most of the air sample concentrations (87%) were less than 5 ppb. However, the presence of airborne TDI greater than 5 ppb indicated the importance of respiratory protection in some situations; therefore, respirator use patterns were studied and summarized. Additionally, this article provides a summary of air sample concentrations at different flexible foam manufacturing job roles. The information on air sampling concentrations and respiratory protection during TDI applications collected in this paper could be useful for product stewardship and industrial hygiene purposes in the industries studied.
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Affiliation(s)
| | | | | | - Mark W Spence
- International Isocyanate Institute, Inc., Mountain Lakes, NJ, USA
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Silva BG, Santos Oliveira JM, Zamariolli Damianovic MHR, Foresti E. Foam aerated biofilm reactor: a novel counter-diffusional process for COD and nitrogen removal from low COD/N effluents. Environ Technol 2022; 43:2671-2683. [PMID: 33616004 DOI: 10.1080/09593330.2021.1893830] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/05/2020] [Accepted: 02/14/2021] [Indexed: 06/12/2023]
Abstract
Counter-diffusional biofilms are efficient in the removal of nitrogen from low strength wastewaters. Although counter-diffusion is usually established using expensive gas-permeable membranes, a polyurethane sheet is used to separate the aerobic and anoxic environments in the novel foam aerated biofilm reactor (FABR). Foam sheets with thicknesses of 10, 5 and 2 mm and synthetic wastewater with COD/N ratios of 5 and 2.5 were evaluated. The 2 mm thick foam reactor did not show good biomass adherence and, therefore, did not show N removal efficiency. The 5 and 10 mm reactors, in both COD/N ratios, showed similar total nitrogen and COD removal performance, up to 60% and 80%, respectively. The denitrification efficiency was close to 100% throughout the experimental period. Nitrification efficiency decreased with microbial growth, which was recovered after removal of excessive biomass. Lower values of polyurethane foam thickness and COD/N ratio did not provide a higher nitrification rate, as expected. The increase in resistance to mass transfer was associated with the growth of biomass attached to the foam rather than to its thickness and resulted in specialization of the microbial communities as revealed by 16S amplicon sequencing. FABR reveals as a promising alternative for simultaneous removal of nitrogen and COD from low COD/N ratio wastewaters.
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Affiliation(s)
- Bruno Garcia Silva
- Biological Processes Laboratory, São Carlos School of Engineering (EESC), University of São Paulo (USP), São Carlos, Brazil
| | - Jean Maikon Santos Oliveira
- Biological Processes Laboratory, São Carlos School of Engineering (EESC), University of São Paulo (USP), São Carlos, Brazil
| | | | - Eugenio Foresti
- Biological Processes Laboratory, São Carlos School of Engineering (EESC), University of São Paulo (USP), São Carlos, Brazil
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Stenholm Å, Hedeland M, Pettersson CE. Neomycin removal using the white rot fungus Trametes versicolor. J Environ Sci Health A Tox Hazard Subst Environ Eng 2022; 57:436-447. [PMID: 35583106 DOI: 10.1080/10934529.2022.2072644] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/06/2022] [Revised: 04/25/2022] [Accepted: 04/26/2022] [Indexed: 06/15/2023]
Abstract
The presence of antibiotic resistance genes in wastewater treatment plants (WWTPs), and in river and lake recipients show the need to develop new antibiotic removal strategies. The aminoglycoside antibiotic class is of special concern since the chemical structure of these compounds limits the choices of removal technologies. The experimental design included fungal mediated in vivo and in vitro experiments. The experiments were performed in Erlenmeyer flasks under non-sterile conditions. In the study, the role of the laccase redox mediator 4-hydroxy benzoic acid (HBA) in the removal of neomycin was investigated. The specific objective of the study was to conclude whether it is possible to use the white rot fungus (WRF) Trametes versicolor to biodegrade neomycin. It was shown that it is feasible to remove 34% neomycin in vitro (excluding living fungal cells) by laccase-HBA mediated extracellular biodegradation. In the in vivo experiments, polyurethane foam (PUF) was used as supporting material to immobilize fungal mycelia on. The presence of living fungal cells facilitated a removal of approximately 80% neomycin in the absence of HBA. Using liquid chromatography-high resolution-mass spectrometry, it was possible to tentatively identify oxidation products of neomycin hydrolysates. The results in this study open up the possibility to implement a pretreatment plant (PTP) aimed for neomycin removal.
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Affiliation(s)
- Åke Stenholm
- Department of Medicinal Chemistry, Analytical Pharmaceutical Chemistry, Uppsala University, Uppsala, Sweden
- Cytiva AB, Uppsala, Sweden
| | - Mikael Hedeland
- Department of Medicinal Chemistry, Analytical Pharmaceutical Chemistry, Uppsala University, Uppsala, Sweden
| | - Curt E Pettersson
- Department of Medicinal Chemistry, Analytical Pharmaceutical Chemistry, Uppsala University, Uppsala, Sweden
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Santiago-Calvo M, Carracedo-Pérez M, Puertas ML, Esteban-Cubillo A, Santaren J, Villafañe F, Rodríguez-Pérez MÁ. Characterization and Properties of Water-Blown Rigid Polyurethane Foams Reinforced with Silane-Modified Nanosepiolites Functionalized with Graphite. Materials (Basel) 2022; 15:381. [PMID: 35009524 DOI: 10.3390/ma15010381] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 10/30/2021] [Revised: 12/17/2021] [Accepted: 12/30/2021] [Indexed: 02/01/2023]
Abstract
In the present study, a promising flame retardant consisting of 80 wt% silane-modified nanosepiolites functionalized with 20 wt% graphite (SFG) is used to obtain a synergistic effect principally focussed on the thermal stability of water-blown rigid polyurethane (RPU) foams. Density, microcellular structure, thermal stability and thermal conductivity are examined for RPU foams reinforced with different contents of SFG (0, as reference material, 2, 4 and 6 wt%). The sample with 6 wt% SFG presents a slightly thermal stability improvement, although its cellular structure is deteriorated in comparison with the reference material. Furthermore, the influence of SFG particles on chemical reactions during the foaming process is studied by FTIR spectroscopy. The information obtained from the chemical reactions and from isocyanate consumption is used to optimize the formulation of the foam with 6 wt% SFG. Additionally, in order to determine the effects of functionalization on SFG, foams containing only silane-modified nanosepiolites, only graphite, or silane-modified nanosepiolites and graphite added separately are studied here as well. In conclusion, the inclusion of SFG in RPU foams allows the best performance to be achieved.
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Sukhawipat N, Saengdee L, Pasetto P, Junthip J, Martwong E. Sustainable Rigid Polyurethane Foam from Wasted Palm Oil and Water Hyacinth Fiber Composite-A Green Sound-Absorbing Material. Polymers (Basel) 2022; 14:201. [PMID: 35012223 DOI: 10.3390/polym14010201] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/12/2021] [Revised: 12/31/2021] [Accepted: 01/02/2022] [Indexed: 12/10/2022] Open
Abstract
A novel rigid sound-absorbing material made from used palm oil-based polyurethane foam (PUF) and water hyacinth fiber (WHF) composite was developed in this research. The NCO index was set at 100, while the WHF content was set at 1%wt with mesh sizes ranging from 80 to 20. The mechanical properties, the morphology, the flammability, and the sound absorption coefficient (SAC) of the PUF composite were all investigated. When the WHF size was reduced from 80 to 20, the compression strength of the PUF increased from 0.33 to 0.47 N/mm2. Furthermore, the use of small fiber size resulted in a smaller pore size of the PUF composite and improved the sound absorption and flammability. A feasible sound-absorbing material was a PUF composite with a WHF mesh size of 80 and an SAC value of 0.92. As a result, PUF derived from both water hyacinth and used palm oil could be a promising green alternative material for sound-absorbing applications.
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Yusuf A, Demirci Y, Maras T, Moon SE, Pil-Im J, Kim JH, Ballikaya S. Experimental and Theoretical Investigation of the Effect of Filler Material on the Performance of Flexible and Rigid Thermoelectric Generators. ACS Appl Mater Interfaces 2021; 13:61275-61285. [PMID: 34905915 DOI: 10.1021/acsami.1c20004] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/14/2023]
Abstract
Thermoelectric generators have found many applications where the heat source can be either flat or curved. For a curved heat source, flexible thermoelectric generators are generally used. A filler material with low thermal conductivity can provide additional mechanical support to the thermoelectric module and can reduce convection and radiation losses. Herein, the effect of three different filler materials on the output performance of rigid and flexible thermoelectric generators is investigated. At first, theoretical models are derived and the experimental study validated the models. The experimental study revealed that the flexible thermoelectric modules outperformed the rigid modules; this is due to the reduction of the number of thermal junctions in the flexible modules and due to the differences in the thermal conductivities of the flexible and rigid substrates. Likewise, among TE modules without filler/with air between the TE legs, with polyurethane foam filler material, and with polydimethylsiloxane filler material, air has the lowest thermal conductivity, and therefore, the thermoelectric generator without filler generates higher output power and higher power density than when the other two filler materials are used. For the fixed temperature gradient, the highest power densities for the flexible and rigid thermoelectric generators without filler are 155 and 137.7 μW/cm2 for temperature gradients of 10.8 and 10.3 °C, respectively.
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Affiliation(s)
- Aminu Yusuf
- Department of Electrical and Electronics Engineering, Istanbul University-Cerrahpaşa, Avcılar, Istanbul 34320, Turkey
| | - Yunus Demirci
- Department of Electrical and Electronics Engineering, Istanbul University-Cerrahpaşa, Avcılar, Istanbul 34320, Turkey
| | - Tugce Maras
- Department of Mechanical Engineering, Marmara University, Kadıköy, Istanbul 34722, Turkey
| | - Seung Eon Moon
- Emerging Nano-Materials Research Section, Electronics and Telecommunications Research Institute, Daejeon 305-700, Republic of Korea
| | - Jong Pil-Im
- Emerging Nano-Materials Research Section, Electronics and Telecommunications Research Institute, Daejeon 305-700, Republic of Korea
| | - Jeong Hun Kim
- Emerging Nano-Materials Research Section, Electronics and Telecommunications Research Institute, Daejeon 305-700, Republic of Korea
| | - Sedat Ballikaya
- Department of Physics, Istanbul University, Fatih, Istanbul 34452, Turkey
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El Khezraji S, Thakur S, Raihane M, López-Manchado MA, Belachemi L, Verdejo R, Lahcini M. Use of Novel Non-Toxic Bismuth Catalyst for the Preparation of Flexible Polyurethane Foam. Polymers (Basel) 2021; 13:polym13244460. [PMID: 34961011 PMCID: PMC8704569 DOI: 10.3390/polym13244460] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/16/2021] [Revised: 12/07/2021] [Accepted: 12/17/2021] [Indexed: 11/16/2022] Open
Abstract
Foam products are one of the largest markets for polyurethane (PU) and are heavily used in many sectors. However, current PU formulations use highly toxic and environmentally unfriendly production processes. Meanwhile, the increasing environmental concerns and regulations are intensifying the research into green and non-toxic products. In this study, we synthesized flexible polyurethane foam (PUF) using different weight percentages (0.025%, 0.05% and 0.1%) of a non-toxic bismuth catalyst. The bismuth-catalyzed foams presented a well evolved cellular structure with an open cell morphology. The properties of the bismuth-catalyzed flexible PUF, such as the mechanical, morphological, kinetic and thermal behaviors, were optimized and compared with a conventional tin-catalyzed PUF. The bismuth-catalyst revealed a higher isocyanate conversion efficiency than the stannous octoate catalyst. When comparing samples with similar densities, the bismuth-catalyzed foams present better mechanical behavior than the tin-catalyzed sample with similar thermal stability. The high solubility of bismuth triflate in water, together with its high Lewis acidity, have been shown to benefit the production of PU foams.
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Affiliation(s)
- Said El Khezraji
- IMED-Lab, Faculty of Sciences and Techniques, Cadi Ayyad University, Avenue Abdelkrim Elkhattabi, B.P. 549, Marrakech 40000, Morocco; (S.E.K.); (M.R.); (L.B.)
- Instituto de Ciencia y Tecnologia de Polimeros, ICTP-CSIC, C/Juan de la Cierva, 3, 28006 Madrid, Spain; (S.T.); (M.A.L.-M.)
| | - Suman Thakur
- Instituto de Ciencia y Tecnologia de Polimeros, ICTP-CSIC, C/Juan de la Cierva, 3, 28006 Madrid, Spain; (S.T.); (M.A.L.-M.)
| | - Mustapha Raihane
- IMED-Lab, Faculty of Sciences and Techniques, Cadi Ayyad University, Avenue Abdelkrim Elkhattabi, B.P. 549, Marrakech 40000, Morocco; (S.E.K.); (M.R.); (L.B.)
| | - Miguel Angel López-Manchado
- Instituto de Ciencia y Tecnologia de Polimeros, ICTP-CSIC, C/Juan de la Cierva, 3, 28006 Madrid, Spain; (S.T.); (M.A.L.-M.)
| | - Larbi Belachemi
- IMED-Lab, Faculty of Sciences and Techniques, Cadi Ayyad University, Avenue Abdelkrim Elkhattabi, B.P. 549, Marrakech 40000, Morocco; (S.E.K.); (M.R.); (L.B.)
| | - Raquel Verdejo
- Instituto de Ciencia y Tecnologia de Polimeros, ICTP-CSIC, C/Juan de la Cierva, 3, 28006 Madrid, Spain; (S.T.); (M.A.L.-M.)
- Correspondence: (R.V.); (M.L.)
| | - Mohammed Lahcini
- IMED-Lab, Faculty of Sciences and Techniques, Cadi Ayyad University, Avenue Abdelkrim Elkhattabi, B.P. 549, Marrakech 40000, Morocco; (S.E.K.); (M.R.); (L.B.)
- Chemical & Biochemical Sciences (CBS), Mohammed VI Polytechnic University, Lot 660, Hay Moulay Rachid, Ben Guerir 43150, Morocco
- Correspondence: (R.V.); (M.L.)
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Lee DN, Gwon K, Nam Y, Lee SJ, Tran NM, Yoo H. Polyurethane Foam Incorporated with Nanosized Copper-Based Metal-Organic Framework: Its Antibacterial Properties and Biocompatibility. Int J Mol Sci 2021; 22:13622. [PMID: 34948419 PMCID: PMC8705956 DOI: 10.3390/ijms222413622] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/14/2021] [Revised: 12/05/2021] [Accepted: 12/17/2021] [Indexed: 11/17/2022] Open
Abstract
Polyurethane foams (PUFs) have attracted attention as biomaterials because of their low adhesion to the wound area and suitability as biodegradable or bioactive materials. The composition of the building blocks for PUFs can be controlled with additives, which provide excellent anti-drug resistance and biocompatibility. Herein, nanosized Cu-BTC (copper(II)-benzene-1,3,5-tricarboxylate) was incorporated into a PUF via the crosslinking reaction of castor oil and chitosan with toluene-2,4-diisocyanate, to enhance therapeutic efficiency through the modification of the surface of PUF. The physical and thermal properties of the nanosized Cu-BTC-incorporated PUF (PUF@Cu-BTC), e.g., swelling ratio, phase transition, thermal gravity loss, and cell morphology, were compared with those of the control PUF. The bactericidal activities of PUF@Cu-BTC and control PUF were evaluated against Pseudomonas aeruginosa, Klebsiella pneumoniae, and methicillin-resistant Staphylococcus aureus. PUF@Cu-BTC exhibited selective and significant antibacterial activity toward the tested bacteria and lower cytotoxicity for mouse embryonic fibroblasts compared with the control PUF at a dose of 2 mg mL-1. The Cu(II) ions release test showed that PUF@Cu-BTC was stable in phosphate buffered saline (PBS) for 24 h. The selective bactericidal activity and low cytotoxicity of PUF@Cu-BTC ensure it is a candidate for therapeutic applications for the drug delivery, treatment of skin disease, and wound healing.
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Affiliation(s)
- Do Nam Lee
- Ingenium College of Liberal Arts (Chemistry), Kwangwoon University, Seoul 01897, Korea; (K.G.); (S.J.L.)
| | - Kihak Gwon
- Ingenium College of Liberal Arts (Chemistry), Kwangwoon University, Seoul 01897, Korea; (K.G.); (S.J.L.)
- Department of Physiology and Biomedical Engineering, Mayo Clinic, Rochester, MN 55902, USA
| | - Yunhee Nam
- Department of Materials Science and Chemical Engineering, Hanyang University, Ansan 15588, Korea; (Y.N.); (N.M.T.)
| | - Su Jung Lee
- Ingenium College of Liberal Arts (Chemistry), Kwangwoon University, Seoul 01897, Korea; (K.G.); (S.J.L.)
| | - Ngoc Minh Tran
- Department of Materials Science and Chemical Engineering, Hanyang University, Ansan 15588, Korea; (Y.N.); (N.M.T.)
| | - Hyojong Yoo
- Department of Materials Science and Chemical Engineering, Hanyang University, Ansan 15588, Korea; (Y.N.); (N.M.T.)
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Abstract
Significance: Negative pressure wound therapy (NPWT) has become a valuable adjunct in the treatment of acute and chronic wounds in several surgical disciplines. Retained foams are among its side effects, and they pose a rare but devastating complication at the site of this therapy, which might be associated with wound-healing complications, infection persistence, repeated surgical revisions, and prolonged antibiotic courses. Recent Advances: In the past 15 years, an increasing number of studies have identified this potential problem. Although the exact incidence remains unknown, initial studies have indicated rates of up to 10% in large collectives being treated by NPWT. Critical Issues: The lack of radiopaque markers does not allow for the visual control of retained foams using plain radiographs. Further imaging methods (e.g., CT and MRI) also do not help in adequate differential diagnosis. The lack of routine documentation of the number, type, and localization of the inserted foam(s) and unplanned surgery with a different surgical team pose risk factors for foam retainment. Future Directions: Introducing new documentation records for wounds treated with NPWT is recommended. At foam removal, all dressing materials should be examined for integrity. The development of foams with radiopaque markers by the industry, such as those routinely used in surgical gauze swabs, might also be a useful step to minimize the risk of foam retainment within wounds.
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Affiliation(s)
- Konstantinos Anagnostakos
- Department of Orthopedics, Center for Orthopedic and Trauma Surgery, Klinikum Saarbrücken, Saarbrücken, Germany
| | - Andreas Thiery
- Department of Orthopedics, Center for Orthopedic and Trauma Surgery, Klinikum Saarbrücken, Saarbrücken, Germany
| | - Ismail Sahan
- Department of Orthopedics, Center for Orthopedic and Trauma Surgery, Klinikum Saarbrücken, Saarbrücken, Germany
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Abd Rahman MS, Ab Kadir MZA, Abd Rahman MS, Osman M, Ungku Amirulddin UA, Mohd Nor SF, Zainuddin NM. The Behavior of Polyurethane Foam-Filled Glass-Fiber-Reinforced Polymer Crossarm Subjected to Lightning Transient Voltage. Materials (Basel) 2021; 14:5628. [PMID: 34640025 DOI: 10.3390/ma14195628] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 06/30/2021] [Revised: 08/31/2021] [Accepted: 09/15/2021] [Indexed: 11/17/2022]
Abstract
The demand for composite materials in high-voltage electrical insulation is escalating over the last decades. In the power system, the composite glass-fiber-reinforced polymer has been used as an alternative to wood and steel crossarm structures due to its superior properties. As a composite, the material is susceptible to multi-aging factors, one of which is the electrical stress caused by continuous and temporary overvoltage. In order to achieve a better insulation performance and higher life expectancy, the distribution of the stresses should firstly be studied and understood. This paper focuses on the simulation work to better understand the stress distribution of the polyurethane foam-filled glass-fiber-reinforced polymer crossarm due to the lightning transient injection. A finite-element-based simulation was carried out to investigate the behavior of the electric field and voltage distribution across the sample using an Ansys Maxwell 3D. Electrical stresses at both outer and inner surfaces of the crossarm during the peak of lightning were analyzed. Analyses on the electric field and potential distribution were performed at different parts of the crossarm and correlated to the physical characteristics and common discharge location observed during the experiment. The results of the electric field on the crossarm indicate that both the outer and internal parts of the crossarm were prone to high field stress.
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Kairytė A, Członka S, Boris R, Vėjelis S. Evaluation of the Performance of Bio-Based Rigid Polyurethane Foam with High Amounts of Sunflower Press Cake Particles. Materials (Basel) 2021; 14:ma14195475. [PMID: 34639873 PMCID: PMC8509374 DOI: 10.3390/ma14195475] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 08/04/2021] [Revised: 09/17/2021] [Accepted: 09/20/2021] [Indexed: 01/16/2023]
Abstract
In the current study, rigid polyurethane foam (PUR) was modified with 10-30 wt.% sunflower press cake (SFP) filler, and its effect on performance characteristics-i.e., rheology, characteristic foaming times, apparent density, thermal conductivity, compressive strength parallel and perpendicular to the foaming directions, tensile strength, and short-term water absorption by partial immersion-was evaluated. Microstructural and statistical analyses were implemented as well. During the study, it was determined that 10-20 wt.% SFP filler showed the greatest positive impact. For instance, the thermal conductivity value improved by 9% and 17%, respectively, while mechanical performance, i.e., compressive strength, increased by 11% and 28% in the perpendicular direction and by 43% and 67% in the parallel direction. Moreover, tensile strength showed 49% and 61% increments, respectively, at 10 wt.% and 20 wt.% SFP filler. Most importantly, SFP filler-modified PUR foams were characterised by two times lower water absorption values and improved microstructures with a reduced average cell size and increased content in closed cells.
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Affiliation(s)
- Agnė Kairytė
- Laboratory of Thermal Insulating Materials and Acoustics, Faculty of Civil Engineering, Institute of Building Materials, Vilnius Gediminas Technical University, Linkmenu Str. 28, LT-08217 Vilnius, Lithuania;
- Correspondence:
| | - Sylwia Członka
- Institute of Polymer & Dye Technology, Lodz University of Technology, 90-924 Lodz, Poland;
| | - Renata Boris
- Laboratory of Composite Materials, Faculty of Civil Engineering, Institute of Building Materials, Vilnius Gediminas Technical University, Linkmenu Str. 28, LT-08217 Vilnius, Lithuania;
| | - Sigitas Vėjelis
- Laboratory of Thermal Insulating Materials and Acoustics, Faculty of Civil Engineering, Institute of Building Materials, Vilnius Gediminas Technical University, Linkmenu Str. 28, LT-08217 Vilnius, Lithuania;
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Pahlevanneshan Z, Deypour M, Kefayat A, Rafienia M, Sajkiewicz P, Esmaeely Neisiany R, Enayati MS. Polyurethane-Nanolignin Composite Foam Coated with Propolis as a Platform for Wound Dressing: Synthesis and Characterization. Polymers (Basel) 2021; 13:3191. [PMID: 34578092 PMCID: PMC8473208 DOI: 10.3390/polym13183191] [Citation(s) in RCA: 20] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/19/2021] [Revised: 09/07/2021] [Accepted: 09/14/2021] [Indexed: 02/03/2023] Open
Abstract
This piece of research explores porous nanocomposite polyurethane (PU) foam synthesis, containing nanolignin (NL), coated with natural antimicrobial propolis for wound dressing. PU foam was synthesized using polyethylene glycol, glycerol, NL, and 1, 6-diisocyanato-hexane (NCO/OH ratio: 1.2) and water as blowing agent. The resultant foam was immersed in ethanolic extract of propolis (EEP). PU, NL-PU, and PU-NL/EEP foams were characterized from mechanical, morphological, and chemical perspectives. NL Incorporation into PU increased mechanical strength, while EEP coating showed lower strength than PU-NL/EEP. Morphological investigations confirmed an open-celled structure with a pore diameter of 150-200 μm, a density of nearly 0.2 g/cm3,, and porosity greater than 85%, which led to significantly high water absorption (267% for PU-NL/EEP). The hydrophilic nature of foams, measured by the contact angle, proved to be increased by NL addition and EEP coating. PU and PU-NL did not show important antibacterial features, while EEP coating resulted in a significant antibacterial efficiency. All foams revealed high biocompatibility toward L929 fibroblasts, with the highest cell viability and cell attachment for PU-NL/EEP. In vivo wound healing using Wistar rats' full-thickness skin wound model confirmed that PU-NL/EEP exhibited an essentially higher wound healing efficacy compared with other foams. Hence, PU-NL/EEP foam could be a promising wound dressing candidate.
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Affiliation(s)
- Zari Pahlevanneshan
- Department of Biomaterials, Tissue Engineering and Nanotechnology, School of Advanced Medical Technologies, Isfahan University of Medical Sciences, Isfahan 81746-73461, Iran
| | - Mohammadreza Deypour
- Polymer Chemistry Research Laboratory, Department of Chemistry, Isfahan 81746-73441, Iran;
| | - Amirhosein Kefayat
- Cancer Prevention Research Center, Department of Oncology, Isfahan University of Medical Sciences, Isfahan 81746-73461, Iran;
| | - Mohammad Rafienia
- Biosensor Research Center, Isfahan University of Medical Sciences, Isfahan 81746-73461, Iran
| | - Paweł Sajkiewicz
- Institute of Fundamental Technological Research, Polish Academy of Sciences, Pawinskiego 5B, 02-106 Warsaw, Poland;
| | - Rasoul Esmaeely Neisiany
- Department of Materials and Polymer Engineering, Hakim Sabzevari University, Sabzevar 96179-76487, Iran
| | - Mohammad Saeid Enayati
- Institute of Fundamental Technological Research, Polish Academy of Sciences, Pawinskiego 5B, 02-106 Warsaw, Poland;
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Sermon A, Hofmann-Fliri L, Zderic I, Agarwal Y, Scherrer S, Weber A, Altmann M, Knobe M, Windolf M, Gueorguiev B. Impact of Bone Cement Augmentation on the Fixation Strength of TFNA Blades and Screws. Medicina (Kaunas) 2021; 57:medicina57090899. [PMID: 34577822 PMCID: PMC8465598 DOI: 10.3390/medicina57090899] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 07/02/2021] [Revised: 08/20/2021] [Accepted: 08/26/2021] [Indexed: 11/16/2022]
Abstract
Background and Objectives: Hip fractures constitute the most debilitating complication of osteoporosis with steadily increasing incidences in the aging population. Their intramedullary nailing can be challenging because of poor anchorage in the osteoporotic femoral head. Cement augmentation of Proximal Femoral Nail Antirotation (PFNA) blades demonstrated promising results by enhancing cut-out resistance in proximal femoral fractures. The aim of this study was to assess the impact of augmentation on the fixation strength of TFN-ADVANCEDTM Proximal Femoral Nailing System (TFNA) blades and screws within the femoral head and compare its effect when they are implanted in centre or anteroposterior off-centre position. Materials and Methods: Eight groups were formed out of 96 polyurethane low-density foam specimens simulating isolated femoral heads with poor bone quality. The specimens in each group were implanted with either non-augmented or cement-augmented TFNA blades or screws in centre or anteroposterior off-centre positions, 7 mm anterior or posterior. Mechanical testing was performed under progressively increasing cyclic loading until failure, in setup simulating an unstable pertrochanteric fracture with a lack of posteromedial support and load sharing at the fracture gap. Varus-valgus and head rotation angles were monitored. A varus collapse of 5° or 10° head rotation was defined as a clinically relevant failure. Results: Failure load (N) for specimens with augmented TFNA head elements (screw/blade centre: 3799 ± 326/3228 ± 478; screw/blade off-centre: 2680 ± 182/2591 ± 244) was significantly higher compared with respective non-augmented specimens (screw/blade centre: 1593 ± 120/1489 ± 41; screw/blade off-centre: 515 ± 73/1018 ± 48), p < 0.001. For both non-augmented and augmented specimens failure load in the centre position was significantly higher compared with the respective off-centre positions, regardless of the head element type, p < 0.001. Augmented off-centre TFNA head elements had significantly higher failure load compared with non-augmented centrally placed implants, p < 0.001. Conclusions: Cement augmentation clearly enhances the fixation stability of TFNA blades and screws. Non-augmented blades outperformed screws in the anteroposterior off-centre position. Positioning of TFNA blades in the femoral head is more forgiving than TFNA screws in terms of failure load.
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Affiliation(s)
- An Sermon
- Department of Traumatology, University Hospitals Gasthuisberg, 3000 Leuven, Belgium;
- Department of Development and Regeneration, KU Leuven, 3000 Leuven, Belgium
| | | | - Ivan Zderic
- AO Research Institute Davos, 7270 Davos, Switzerland; (L.H.-F.); (I.Z.); (M.W.)
| | | | - Simon Scherrer
- DePuy Synthes Trauma, 4528 Zuchwil, Switzerland; (S.S.); (A.W.); (M.A.)
| | - André Weber
- DePuy Synthes Trauma, 4528 Zuchwil, Switzerland; (S.S.); (A.W.); (M.A.)
| | - Martin Altmann
- DePuy Synthes Trauma, 4528 Zuchwil, Switzerland; (S.S.); (A.W.); (M.A.)
| | - Matthias Knobe
- Department of Trauma Surgery, Cantonal Hospital Lucerne, 6000 Lucerne, Switzerland;
| | - Markus Windolf
- AO Research Institute Davos, 7270 Davos, Switzerland; (L.H.-F.); (I.Z.); (M.W.)
| | - Boyko Gueorguiev
- AO Research Institute Davos, 7270 Davos, Switzerland; (L.H.-F.); (I.Z.); (M.W.)
- Correspondence: ; Tel.: +41-78-665-66-74
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Borowicz M, Isbrandt M, Paciorek-Sadowska J. Effect of New Eco-Polyols Based on PLA Waste on the Basic Properties of Rigid Polyurethane and Polyurethane/Polyisocyanurate Foams. Int J Mol Sci 2021; 22:ijms22168981. [PMID: 34445688 PMCID: PMC8396538 DOI: 10.3390/ijms22168981] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/28/2021] [Revised: 08/12/2021] [Accepted: 08/19/2021] [Indexed: 12/30/2022] Open
Abstract
The aim of the presented research was to obtain two new eco-polyols based on waste polylactide (PLA) and to check the effect on the properties of rigid polyurethane (RPU) foams and, based on these, rigid polyurethane/polyisocyanurate (RPU/PIR) foams. The synthesis of eco-polyols was based on the transesterification reaction of melted PLA with diethylene glycol in the presence of an organometallic catalyst. Properties of the obtained eco-polyols were examined for their potential as raw materials for synthesis of rigid polyurethane and polyisocyanurate foams, i.e., hydroxyl value, acid value, density, viscosity, pH, water content. Spectroscopic studies (FTIR, 1H NMR and 13C NMR) were also carried out. Results of these tests confirmed the assumed chemical structure of the new polyols. RPU and RPU/PIR foam formulations were developed based on the obtained analytical results. Partial replacement of petrochemical polyol by eco-polyols in RPU and RPU/PIR foams decreased the value of apparent density, compressive strength, brittleness and water absorption. Moreover, all foams modified by eco-polyols showed higher resistance to aging. All RPU/PIR foams and most PRU foams modified by eco-polyols from waste PLA had better functional properties than the reference foams based on petrochemical polyol.
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Tiwari RR, Raghavan S. Spirometric Measurement among Polyurethane Foam Mattress-making Workers of India. Indian J Community Med 2021; 46:313-316. [PMID: 34321750 PMCID: PMC8281860 DOI: 10.4103/ijcm.ijcm_909_20] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/19/2020] [Accepted: 03/09/2021] [Indexed: 11/29/2022] Open
Abstract
Background: The polyurethane foam (PUF) mattress-making workers are exposed to isocyanates which are known respiratory toxicants and cause effect on pulmonary volumes and flows. Thus, the study was with a rationale to measure the changes in pulmonary flow and volumes due to isocyanates among PUF mattress-making workers. Materials and Methods: The study included 183 male workers from seven PUF making units of western and northern India. Using the interview technique as a tool for data collection, demographic and occupational details of the subjects were recorded on the predesigned and pretested pro forma. The mean of spirometric parameters was compared using one-way ANOVA and t-test. The relation between spirometric parameters and anthropometric parameters was analyzed using the correlation coefficient. Results: The spirometry showed that out of 183 participants, 165 (90.2%) subjects had normal spirometry, 13 (7.1%) had restrictive impairment, and 4 (2.2%) had obstructive impairment. All the mean spirometric values showed a declining trend with increasing age, while only forced expiratory volume in first second and forced vital capacity25%–75% showed a declining trend with increasing duration of employment. The spirometric measurements had a negative correlation with age and positive correlation with height. Conclusion: The spirometric values representing the airway flow were affected. The associated factors include age and duration of exposure.
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Affiliation(s)
- Rajnarayan Ramshankar Tiwari
- Department of Industrial Hygiene, ICMR-National Institute for Research in Environmental Health, Bhopal, Madhya Pradesh, India
| | - Sampathraju Raghavan
- ICMR-Regional Occupational Health Centre (Southern), Bengaluru, Karnataka, India
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Kiss G, Rusu G, Bandur G, Hulka I, Romecki D, Péter F. Advances in Low-Density Flexible Polyurethane Foams by Optimized Incorporation of High Amount of Recycled Polyol. Polymers (Basel) 2021; 13:1736. [PMID: 34073296 DOI: 10.3390/polym13111736] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/15/2021] [Revised: 05/18/2021] [Accepted: 05/22/2021] [Indexed: 11/16/2022] Open
Abstract
An industrially manufactured recycled polyol, obtained by acidolysis process, was for the first time proved to be a possible replacement of the reference fossil-based polyol in a low-density formulation suitable for industrial production of flexible polyurethane foams. The influence of increasing recycled polyol amounts on the properties of the polyurethane foam has been studied, also performing foam emission tests to evaluate the environmental impact. Using 10 pbw recycled polyol in the standard formulation, significant differences of the physical properties were not observed, but increase of the recycled polyol amount to 30 pbw led to a dramatic decrease of the foam air flow and a very tight foam. To overcome this drawback, N,N′-bis[3-(dimethylamino)propyl]urea was selected as tertiary amine catalyst, enabling the preservation of foam properties even at high recycled polyol level (30 pbw). Foam emission data demonstrated that this optimized foam formulation also led to an important reduction of volatile organic compounds. The results open the way for further optimization studies in low-density flexible polyurethane foam formulations, to increase the reutilization of the polyurethane waste and reduce the amount of petroleum-based raw materials.
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50
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Al-Atroush ME, Shabbir O, Almeshari B, Waly M, Sebaey TA. A Novel Application of the Hydrophobic Polyurethane Foam: Expansive Soil Stabilization. Polymers (Basel) 2021; 13:1335. [PMID: 33921753 PMCID: PMC8073868 DOI: 10.3390/polym13081335] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/15/2021] [Revised: 04/11/2021] [Accepted: 04/12/2021] [Indexed: 11/23/2022] Open
Abstract
The reversible shrink-swell behavior of expansive soil imposes a serious challenge that threatens the overlying structures' safety and durability. Traditional chemical additives such as lime and cement still exhibit satisfying performance over their counterparts in terms of swelling potential reduction. Nevertheless, significant concerns are associated with these chemicals, in addition to their environmental impact. This paper proposes a novel application of the closed-cell one-component hydrophobic polyurethane foam (HPUF) to stabilize the swelling soil. An extensive experimental study was performed to assess the efficiency of HPUF in mitigating both the swelling and shrinkage response of high montmorillonite content expansive soil. Expansive soil was injected/mixed with different weight ratios of the proposed stabilizer, and the optimum mixing design and injection percentage of the foam resin were identified to be ranged from 10% to 15%. The shrink-swell behaviors of both injected and noninjected samples were compared. Results of this comparison confirmed that HPUF could competently reduce both the swelling potential and the shrinkage cracking of the reactive expansive soil, even after several wet-shrink cycles.
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Affiliation(s)
- Mohamed Ezzat Al-Atroush
- Department of Engineering Management, College of Engineering, Prince Sultan University, Riyadh 11543, Saudi Arabia; (O.S.); (B.A.); (T.A.S.)
| | - Omar Shabbir
- Department of Engineering Management, College of Engineering, Prince Sultan University, Riyadh 11543, Saudi Arabia; (O.S.); (B.A.); (T.A.S.)
| | - Bandar Almeshari
- Department of Engineering Management, College of Engineering, Prince Sultan University, Riyadh 11543, Saudi Arabia; (O.S.); (B.A.); (T.A.S.)
| | - Mohamed Waly
- Department of Medical Equipment Technology, College of Applied Medical Sciences, Majmaah University, Majmaah 15341, Saudi Arabia;
| | - Tamer A. Sebaey
- Department of Engineering Management, College of Engineering, Prince Sultan University, Riyadh 11543, Saudi Arabia; (O.S.); (B.A.); (T.A.S.)
- Mechanical Design and Production Department, Faculty of Engineering, Zagazig University, Zagazig 44523, Egypt
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