1
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Chen G, Adibi A, Jubinville D, Hao C, Yan N, Mekonnen TH. Rubber-lignin-ammonium polyphosphate bio-composite foams: Fabrication, thermomechanical properties and flame retardancy. Int J Biol Macromol 2024; 280:135884. [PMID: 39317292 DOI: 10.1016/j.ijbiomac.2024.135884] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/28/2024] [Revised: 09/10/2024] [Accepted: 09/19/2024] [Indexed: 09/26/2024]
Abstract
Bio-composite foams based on Epoxidized Natural Rubber (ENR) filled with lignin (LG) and ammonium polyphosphate (APP) were fabricated via batch foaming. The addition of APP accelerated the foaming process at lower temperatures. Pre-mixing induced ionic and hydrogen bonding between the LG and the APP particles, which reduced crosslinking between LG and ENR. The resulting ENR bio-composite foams with LG/APP exhibited a significant increase in compressive strength (up to 700 %) and modulus (up to 600 %) compared to the ENR foam baseline. Furthermore, the LG/APP foams demonstrated lower thermal conductivity than both the ENR foam baseline and foams containing only LG or APP, attributed to optimal thermal conduction in the solid phase and convection within the pore cells. The combination of APP and LG produced synergistic effects, with phosphorus (from APP) and high carbon content (from LG) enhancing flame-retardant efficiency. This study highlights the potential of these sustainable bio-composite foams for applications requiring enhanced thermal insulation and flame retardancy attributes for insulation and other practical applications.
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Affiliation(s)
- Guowei Chen
- Department of Chemical Engineering, Waterloo Institute for Nanotechnology, Institute of Polymer Research, University of Waterloo, Waterloo, ON, Canada
| | - Azin Adibi
- Department of Chemical Engineering, Waterloo Institute for Nanotechnology, Institute of Polymer Research, University of Waterloo, Waterloo, ON, Canada
| | - Dylan Jubinville
- Department of Chemical Engineering, Waterloo Institute for Nanotechnology, Institute of Polymer Research, University of Waterloo, Waterloo, ON, Canada
| | - Cheng Hao
- Department of Chemical Engineering and Applied Chemistry, University of Toronto, Toronto, ON, Canada
| | - Ning Yan
- Department of Chemical Engineering and Applied Chemistry, University of Toronto, Toronto, ON, Canada
| | - Tizazu H Mekonnen
- Department of Chemical Engineering, Waterloo Institute for Nanotechnology, Institute of Polymer Research, University of Waterloo, Waterloo, ON, Canada.
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2
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Bhardwaj S, Singh S, Dev K, Chhajed M, Maji PK. Harnessing the Flexibility of Lightweight Cellulose Nanofiber Composite Aerogels for Superior Thermal Insulation and Fire Protection. ACS APPLIED MATERIALS & INTERFACES 2024; 16:18075-18089. [PMID: 38560888 DOI: 10.1021/acsami.4c01803] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 04/04/2024]
Abstract
Thermally insulating materials from renewable and readily available resources are in high demand for ecologically beneficial applications. Cellulose aerogels made from lignocellulosic waste have various advantages. However, they are fragile and breakable when bent or compressed. In addition, cellulose aerogels are flammable and weather-sensitive. Hence, to overcome these problems, this work included the preparation of polyurethane (PU)-based cellulose nanofiber (CNF) aerogels that had flexibility, flame retardancy, and thermal insulation. Methyl trimethoxysilane (MTMS) and water-soluble ammonium polyphosphate (APP) were added to improve the cross-linking, hydrophobicity, and flame-retardant properties of aerogels. The flexibility of chemically cross-linked CNF aerogels is enhanced through the incorporation of polyurethane via the wet coagulating process. The aerogels obtained during this study have exhibited low weight (density: 35.3-91.96 kg/m3) together with enhanced hydrophobic properties, flame retardancy, and decreased thermal conductivity (26.7-36.7 mW/m K at 25 °C). Additionally, the flame-retardant properties were comprehensively examined and the underlying mechanism was deduced. The aerogels prepared in this study are considered unique in the nanocellulose aerogel category due to their integrated structural and performance benefits. The invention is considered to substantially contribute to the large-scale manufacture and use of insulation in construction, automobiles, and aerospace.
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Affiliation(s)
- Shakshi Bhardwaj
- Department of Polymer and Process Engineering, Indian Institute of Technology Roorkee, Saharanpur Campus, Saharanpur 247001, India
| | - Shiva Singh
- Department of Polymer and Process Engineering, Indian Institute of Technology Roorkee, Saharanpur Campus, Saharanpur 247001, India
| | - Keshav Dev
- Department of Chemistry, Indian Institute of Technology Roorkee, Roorkee 247667, India
| | - Monika Chhajed
- Department of Polymer and Process Engineering, Indian Institute of Technology Roorkee, Saharanpur Campus, Saharanpur 247001, India
| | - Pradip K Maji
- Department of Polymer and Process Engineering, Indian Institute of Technology Roorkee, Saharanpur Campus, Saharanpur 247001, India
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3
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Woźniak-Budych M, Staszak K, Wieszczycka K, Bajek A, Staszak M, Roszkowski S, Giamberini M, Tylkowski B. Microplastic label in microencapsulation field - Consequence of shell material selection. JOURNAL OF HAZARDOUS MATERIALS 2024; 465:133000. [PMID: 38029585 DOI: 10.1016/j.jhazmat.2023.133000] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/06/2023] [Revised: 11/10/2023] [Accepted: 11/11/2023] [Indexed: 12/01/2023]
Abstract
Plastics make our lives easier in many ways; however, if they are not appropriately disposed of or recycled, they may end up in the environment where they stay for centuries and degrade into smaller and smaller pieces, called microplastics. Each year, approximately 42000 tonnes of microplastics end up in the environment when products containing them are used. According to the European Chemicals Agency (ECHA) one of the significant sources of microplastics are microcapsules formulated in home care and consumer care products. As part of the EU's plastics strategy, ECHA has proposed new regulations to ban intentionally added microplastics starting from 2022. It means that the current cross-linked microcapsules widely applied in consumer goods must be transformed into biodegradable shell capsules. The aim of this review is to provide the readers with a comprehensive and in-depth understanding of recent developments in the art of microencapsulation. Thus, considering the chemical structure of the capsule shell's materials, we discuss whether microcapsules should also be categorized as microplastic and therefore, feared and avoided or whether they should be used despite the persisting concern.
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Affiliation(s)
- Marta Woźniak-Budych
- NanoBioMedical Centre, Adam Mickiewicz University, Wszechnicy Piastowskiej 3, 61-614 Poznan, Poland
| | - Katarzyna Staszak
- Institute of Technology and Chemical Engineering, Poznan University of Technology, Berdychowo 4, 60-965 Poznan, Poland
| | - Karolina Wieszczycka
- Institute of Technology and Chemical Engineering, Poznan University of Technology, Berdychowo 4, 60-965 Poznan, Poland
| | - Anna Bajek
- Tissue Engineering Department, Chair of Urology and Andrology, Ludwik Rydygier Collegium Medicum in Bydgoszcz, Nicolaus Copernicus University in Torun, ul. Karlowicza str 24, 85-092 Bydgoszcz, Poland
| | - Maciej Staszak
- Institute of Technology and Chemical Engineering, Poznan University of Technology, Berdychowo 4, 60-965 Poznan, Poland
| | - Szymon Roszkowski
- Department of Geriatrics, Ludwik Rydygier Collegium Medicum in Bydgoszcz, Nicolaus Copernicus University in Torun, ul. Jagiellonska 13/15, 85-067 Bydgoszcz, Poland
| | - Marta Giamberini
- Department of Chemical Engineering (DEQ), Universitat Rovira i Virgili, Av. Països Catalans, 26, 43007 Tarragona, Spain
| | - Bartosz Tylkowski
- Eurecat, Centre Tecnològic de Catalunya, Unitat de Tecnologia Química, Marcel·lí Domingo 2, 43007 Tarragona, Spain; Department of Clinical Neuropsychology, Faculty of Health Science, Ludwik Rydygier Collegium Medicum in Bydgoszcz, Nicolaus Copernicus University in Torun, ul. Sklodowskiej Curie 9, 85-094 Bydgoszcz, Poland.
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4
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Amariei G, Lahn Henriksen M, Klarskov P, Hinge M. In-line quantitative estimation of ammonium polyphosphate flame retardant in polyolefins via industrial hyperspectral imaging system and machine learning. WASTE MANAGEMENT (NEW YORK, N.Y.) 2023; 170:1-7. [PMID: 37531740 DOI: 10.1016/j.wasman.2023.07.026] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/26/2023] [Revised: 07/04/2023] [Accepted: 07/23/2023] [Indexed: 08/04/2023]
Abstract
Due to developments in European legislation, several halogenated flame retardants are banned due to their toxicity, and the use of phosphor-based flame retardants in plastics is increasing. A revision of ammonium polyphosphate (APP) flame retardant revealed that it is an eye irritant and toxic, thus posing a health issue. Hence APP identification is needed for enabling safe recycling of plastic waste streams. Herein an industrial in-line method for quantitative estimation of APP in low density polyethylene (LDPE) and polypropylene (PP) is demonstrated, by using an industrial hyperspectral imaging system (955 to 1700 nm) and principal component analysis (PCA). Spectra of plastic samples with varying concentrations of APP were applied to build and calibrate a quantitative determination method. PCA and band area ratios (of selected bands) were made and fitted with continuous functions for concentration determination. The plastic samples were characterised by elemental analysis, attenuated total reflection, differential scanning calorimetry, and thermogravimetric analysis. The PCA model outperforms the band area ratio model and predicts APP concentrations between 24.3 and 1.5 wt% in LDPE (R2 = 0.98) and 20.0 and 1.7 wt% in PP (R2 = 0.97). Unknown samples with APP ranging from 23.7 to 2.7 wt% in LDPE and from 18.6 to 2.3 wt% in PP were predicted and correlated to the actual concentrations. The proposed approach is valuable for the plastic recyclers and waste management industries where inline concentration determination of flame retardants is key.
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Affiliation(s)
- Georgiana Amariei
- Plastic and Polymer Engineering, Department of Biological and Chemical Engineering, Aarhus University, Aabogade 40, DK-8200 Aarhus N., Denmark
| | - Martin Lahn Henriksen
- Plastic and Polymer Engineering, Department of Biological and Chemical Engineering, Aarhus University, Aabogade 40, DK-8200 Aarhus N., Denmark
| | - Pernille Klarskov
- Terahertz Photonics, Department of Electrical and Computer Engineering, Aarhus University, Finlandsgade 22, DK-8200 Aarhus N, Denmark
| | - Mogens Hinge
- Plastic and Polymer Engineering, Department of Biological and Chemical Engineering, Aarhus University, Aabogade 40, DK-8200 Aarhus N., Denmark.
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5
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Delatorre FM, Cupertino GFM, Pereira AKS, de Souza EC, da Silva ÁM, Ucella Filho JGM, Saloni D, Profeti LPR, Profeti D, Dias Júnior AF. Photoluminous Response of Biocomposites Produced with Charcoal. Polymers (Basel) 2023; 15:3788. [PMID: 37765642 PMCID: PMC10536408 DOI: 10.3390/polym15183788] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/14/2023] [Revised: 09/06/2023] [Accepted: 09/08/2023] [Indexed: 09/29/2023] Open
Abstract
Due to the possible effects of global warming, new materials that do not have a negative impact on the environment are being studied. To serve a variety of industries and outdoor applications, it is necessary to consider the impact of photoluminosity on the performance of biocomposites in order to accurately assess their durability characteristics and prevent substantial damage. Exposure to photoluminosity can result in adverse effects such as discoloration, uneven surface, loss of mass, and manipulation of the intrinsic mechanical properties of biocomposites. This study aims to evaluate general charcoal from three pyrolysis temperatures to understand which charcoal is most suitable for photoluminosity and whether higher pyrolysis temperatures have any significant effect on photoluminosity. Porosity, morphology, Fourier transform infrared spectroscopy (FTIR), and X-ray photoelectron spectroscopy of charcoal were analyzed. Charcoal obtained at a temperature of 800 °C demonstrates remarkable potential as a bioreinforcement in polymeric matrices, attributable to its significantly higher porosity (81.08%) and hydrophobic properties. The biocomposites were characterized for flexural strength, tensile strength, scanning electron microscopy (SEM), FTIR, and x-ray diffraction (XRD). The results showed an improvement in tensile strength after exposure to photoluminosity, with an increase of 69.24%, 68.98%, and 54.38% at temperatures of 400, 600, and 800 °C, respectively, in relation to the treatment control. It is notorious that the tensile strength and modulus of elasticity after photoluminosity initially had a negative impact on mechanical strength, the incorporation of charcoal from higher pyrolysis temperatures showed a substantial increase in mechanical strength after exposure to photoluminosity, especially at 800 °C with breaking strength of 53.40 MPa, and modulus of elasticity of 4364.30 MPA. Scanning electron microscopy revealed an improvement in morphology, with a decrease in roughness at 800 °C, which led to greater adhesion to the polyester matrix. These findings indicate promising prospects for a new type of biocomposite, particularly in comparison with other polymeric compounds, especially in engineering applications that are subject to direct interactions with the weather.
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Affiliation(s)
- Fabíola Martins Delatorre
- Department of Forestry and Wood Sciences, Federal University of Espírito Santo (UFES), Av. Governador Lindemberg, 316, Jerônimo Monteiro 29550-000, ES, Brazil
| | - Gabriela Fontes Mayrinck Cupertino
- Department of Forestry and Wood Sciences, Federal University of Espírito Santo (UFES), Av. Governador Lindemberg, 316, Jerônimo Monteiro 29550-000, ES, Brazil
| | - Allana Katiussya Silva Pereira
- Department of Forest Sciences, "Luiz de Queiroz" College of Agriculture, University of São Paulo (ESALQ/USP). Av. Pádua Dias, 11, Piracicaba 13418-900, SP, Brazil
| | - Elias Costa de Souza
- Institute of Xingu Studies, Federal University of South and Southeast Pará (UNIFESSPA), Subdivision Cidade nova, QD 15, Sector 15, São Félix do Xingu 68380-000, PA, Brazil
| | - Álison Moreira da Silva
- Department of Forest Sciences, "Luiz de Queiroz" College of Agriculture, University of São Paulo (ESALQ/USP). Av. Pádua Dias, 11, Piracicaba 13418-900, SP, Brazil
| | - João Gilberto Meza Ucella Filho
- Department of Forestry and Wood Sciences, Federal University of Espírito Santo (UFES), Av. Governador Lindemberg, 316, Jerônimo Monteiro 29550-000, ES, Brazil
| | - Daniel Saloni
- Department of Forest Biomaterials, College of Natural Resources, North Carolina State University, Raleigh, NC 27695, USA
| | | | - Demetrius Profeti
- Department of Chemistry and Physics, Federal University of Espírito Santo (UFES), Alegre 29500-000, ES, Brazil
| | - Ananias Francisco Dias Júnior
- Department of Forestry and Wood Sciences, Federal University of Espírito Santo (UFES), Av. Governador Lindemberg, 316, Jerônimo Monteiro 29550-000, ES, Brazil
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6
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Wang J, Yu S, Xiao S. Research progress of triazine flame retardants. Macromol Res 2023. [DOI: 10.1007/s13233-023-00157-2] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 04/05/2023]
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7
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Kumar D, Mandal S, Bailey JV, Flood BE, Jones RS. Fluoride and gallein inhibit polyphosphate accumulation by oral pathogen Rothia dentocariosa. Lett Appl Microbiol 2023; 76:ovad017. [PMID: 36715153 PMCID: PMC9990172 DOI: 10.1093/lambio/ovad017] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/11/2022] [Accepted: 01/27/2023] [Indexed: 01/31/2023]
Abstract
The uptake and storage of extracellular orthophosphate (Pi) by polyphosphate (polyP) accumulating bacteria may contribute to mineral dissolution in the oral cavity. To test the effect of potential inhibitors of polyP kinases on Rothia dentocariosa, gallein (0, 25, 50, and 100 μM) and fluoride (0, 50, and 100 ppm) were added to R. dentocariosa cultures grown in brain-heart infusion broth. At a late log growth phase (8 h), extracellular Pi was measured using an ascorbic acid assay, and polyP was isolated from bacterial cells treated with RNA/DNAases using a neutral phenol/chloroform extraction. Extracts were hydrolyzed and quantified as above. Gallein and fluoride had minor effects on bacterial growth with NaF having a direct effect on media pH. Gallein (≥25 μM) and fluoride (≥50 ppm) attenuated the bacterial drawdown of extracellular Pi by 56.7% (P < 0.05) and 37.3% (P < 0.01). There was a corresponding polyP synthesis decrease of 73.2% (P < 0.0001) from gallein and 83.1% (P < 0.0001) from fluoride. Attenuated total reflectance-Fourier-transform infrared spectroscopy validated the presence of polyP and its reduced concentration in R. dentocariosa bacterial cells following gallein and fluoride treatment. Rothia dentocariosa can directly change extracellular Pi and accumulate intracellular polyP, but the mechanism is attenuated by gallein and NaF.
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Affiliation(s)
- Dhiraj Kumar
- Department of Developmental and Surgical Sciences, University of Minnesota, Minneapolis, MN 55455, USA
| | - Subhrangshu Mandal
- Department of Earth and Environmental Sciences, University of Minnesota, Minneapolis, MN 55455, USA
| | - Jake V Bailey
- Department of Earth and Environmental Sciences, University of Minnesota, Minneapolis, MN 55455, USA
| | - Beverly E Flood
- Department of Earth and Environmental Sciences, University of Minnesota, Minneapolis, MN 55455, USA
| | - Robert S Jones
- Department of Developmental and Surgical Sciences, University of Minnesota, Minneapolis, MN 55455, USA
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8
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A Novel Approach to Charcoal Fine Waste: Sustainable Use as Filling of Polymeric Matrices. Polymers (Basel) 2022; 14:polym14245525. [PMID: 36559891 PMCID: PMC9785315 DOI: 10.3390/polym14245525] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/02/2022] [Revised: 11/29/2022] [Accepted: 12/12/2022] [Indexed: 12/23/2022] Open
Abstract
Most composites produced come from fossil fuel sources. Renewable strategies are needed for the production of composites. Charcoal fines are considered waste and an alternative for the production of biocomposites. The charcoal fines resulting from the pyrolysis of any biomass are an efficient alternative for the production of green composites. Studies to understand how the pyrolysis parameters influence the properties of this material for the production of biocomposites are necessary. Charcoal has a high carbon content and surface area, depending on final production temperatures. This study aims to evaluate charcoal fines as potential reinforcing agents in biocomposites. This study investigated for the first time charcoal fines from three pyrolysis temperatures (400, 600, and 800 °C) to identify the most suitable charcoal for use as a raw material in the production of carbon biocomposites with 30% by weight incorporated into a polyester matrix composite. Apparent density, porosity, morphology, and immediate chemical composition and Fourier transform infrared spectroscopy (FTIR) and X-ray photoelectron spectroscopy (XPS) of charcoal fines were evaluated. The charcoal fines produced at 800 °C showed interesting potential as polymeric matrix fillers due to their higher porosity (81.08%), fixed carbon content (96.77%), and hydrophobicity. The biocomposites were analyzed for flexural and tensile strength and scanning electron microscopy. The results revealed an improvement in resistance at elevated temperatures, especially at 800 °C, with higher breaking strength (84.11 MPa), modulus of elasticity (4064.70 MPa), and traction (23.53 MPa). Scanning electron microscopy revealed an improvement in morphology, with a decrease in roughness at 800 °C, which caused greater adhesion to the polyester matrix. These results revealed a promising new biocomposite compared to other natural lignocellulosic polymeric composites (NLFs) in engineering applications.
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9
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Song B, Zhu X, Wang W, Wang L, Pei X, Qian X, Liu L, Xu Z. Toughening of melamine-formaldehyde foams and advanced applications based on functional design. J IND ENG CHEM 2022. [DOI: 10.1016/j.jiec.2022.11.069] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
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10
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Antimicrobial Activity of a Titanium Dioxide Additivated Thermoset. Catalysts 2022. [DOI: 10.3390/catal12080829] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/01/2023] Open
Abstract
The transmission of pathogens via surfaces poses a major health problem, particularly in hospital environments. Antimicrobial surfaces can interrupt the path of spread, while photocatalytically active titanium dioxide (TiO2) nanoparticles have emerged as an additive for creating antimicrobial materials. Irradiation of such particles with ultraviolet (UV) light leads to the formation of reactive oxygen species that can inactivate bacteria. The aim of this research was to incorporate TiO2 nanoparticles into a cellulose-reinforced melamine-formaldehyde resin (MF) to obtain a photocatalytic antimicrobial thermoset, to be used, for example, for device enclosures or tableware. To this end, composites of MF with 5, 10, 15, and 20 wt% TiO2 were produced by ultrasonication and hot pressing. The incorporation of TiO2 resulted in a small decrease in tensile strength and little to no decrease in Shore D hardness, but a statistically significant decrease in the water contact angle. After 48 h of UV irradiation, a statistically significant decrease in tensile strength for samples with 0 and 10 wt% TiO2 was measured but with no statistically significant differences in Shore D hardness, although a statistically significant increase in surface hydrophilicity was measured. Accelerated methylene blue (MB) degradation was measured during a further 2.5 h of UV irradiation and MB concentrations of 12% or less could be achieved. Samples containing 0, 10, and 20 wt% TiO2 were investigated for long-term UV stability and antimicrobial activity. Fourier-transform infrared spectroscopy revealed no changes in the chemical structure of the polymer, due to the incorporation of TiO2, but changes were detected after 500 h of irradiation, indicating material degradation. Specimens pre-irradiated with UV for 48 h showed a total reduction in Escherichia coli when exposed to UV irradiation.
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11
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Han LX, Zhao ZY, Deng C, Wang YZ. Piperazine/Alkene-Containing Phosphoramide Oligomer for the Intumescent Flame Retardation of EPDM Rubber. Polym Degrad Stab 2022. [DOI: 10.1016/j.polymdegradstab.2022.109990] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
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12
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Shape-controlled synthesis of sodium zincate mesoporous structures based on sulfonated melamine formaldehyde and their application as catalysts for Biginelli reaction. J Mol Struct 2021. [DOI: 10.1016/j.molstruc.2021.130028] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
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13
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Enhance the interaction between ammonium polyphosphate and epoxy resin matrix through hydrophobic modification with cationic latex. Colloids Surf A Physicochem Eng Asp 2021. [DOI: 10.1016/j.colsurfa.2020.125917] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
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14
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Bakry A, Awad FS, Bobb JA, El-Shall MS. Multifunctional Binding Sites on Nitrogen-Doped Carboxylated Porous Carbon for Highly Efficient Adsorption of Pb(II), Hg(II), and Cr(VI) Ions. ACS OMEGA 2020; 5:33090-33100. [PMID: 33403271 PMCID: PMC7774276 DOI: 10.1021/acsomega.0c04695] [Citation(s) in RCA: 14] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 09/23/2020] [Accepted: 12/02/2020] [Indexed: 06/12/2023]
Abstract
Heavy metal ions represent one of the most toxic and environmentally harmful pollutants of water sources. This work reports the development of a novel chelating nitrogen-doped carboxylated porous carbon (ND-CPC) adsorbent for the effective removal of the heavy metal ions Pb(II), Hg(II), and Cr(VI) from contaminated and polluted water sources. The ND-CPC adsorbent is designed to combine four different types of nitrogen functional groups (graphitic, pyrrolic, pyridinic, and pyridine oxide) with the carboxylic acid functional groups within a high surface area of 1135 ± 20 m2/g of the porous carbon structure. The ND-CPC adsorbent shows exceptionally high adsorption affinity for Pb(II) with a capacity of 721 ± 14 mg/g in addition to high uptake values of 257 ± 5 and 104 ± 2 mg/g for Hg(II) and Cr(VI), respectively. The high adsorption capacity is also coupled with fast kinetics where the equilibrium time required for the 100% removal of Pb(II) from 50 ppb and 10 ppm concentrations is 30 s and 60 min, respectively. Even with the very high concentration of 700 ppm, 74% uptake of Pb(II) is achieved within 90 min. Removal efficiencies of 100% of Pb(II), 96% of Hg(II), 91% of Cu(II), 82% of Zn(II), 25% of Cd(II), and 13% of Ni(II) are achieved from a solution containing 10 ppm concentrations of these ions, thus demonstrating excellent selectivity for Pb(II), Hg(II), and Cu(II) ions. Regeneration of the ND-CPC adsorbent shows excellent desorption efficiencies of 99 and 95% for Pb(II) and Cr(VI) ions, respectively. Because of the fast adsorption kinetics, high removal capacity and excellent regeneration, stability, and reusability, the ND-CPC is proposed as a highly efficient remediation adsorbent for the solid-phase removal of Pb(II), Hg(II), and Cr(VI) from contaminated water.
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Affiliation(s)
- Ayyob
M. Bakry
- Department
of Chemistry, Virginia Commonwealth University, Richmond, Virginia 23284, United States
- Department
of Chemistry, Faculty of Science, Jazan
University, Jazan 45142, Saudi Arabia
| | - Fathi S. Awad
- Department
of Chemistry, Virginia Commonwealth University, Richmond, Virginia 23284, United States
- Chemistry
Department, Faculty of Science, Mansoura
University, Mansoura 35516, Egypt
| | - Julian A. Bobb
- Department
of Chemistry, Virginia Commonwealth University, Richmond, Virginia 23284, United States
| | - M. Samy El-Shall
- Department
of Chemistry, Virginia Commonwealth University, Richmond, Virginia 23284, United States
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15
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High‐efficiency
ammonium polyphosphate intumescent encapsulated polypropylene flame retardant. J Appl Polym Sci 2020. [DOI: 10.1002/app.50413] [Citation(s) in RCA: 17] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
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16
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Pan Y, Luo Z, Wang B. Cross-Linking Modification of Ammonium Polyphosphate via Ionic Exchange and Self-Assembly for Enhancing the Fire Safety Properties of Polypropylene. Polymers (Basel) 2020; 12:polym12112761. [PMID: 33238514 PMCID: PMC7700432 DOI: 10.3390/polym12112761] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/27/2020] [Revised: 11/16/2020] [Accepted: 11/20/2020] [Indexed: 11/24/2022] Open
Abstract
Modified ammonium polyphosphate (MAPP) was prepared as a novel mono-component intumescent flame retardant (IFR) via the ionic exchange between ammonium polyphosphate (APP) and piperazine sulfonate, which is synthesized by self-assembly using 1-(2-aminoethyl) piperazine (AEP) and p-aminobenzene sulfonic acid (ASC) as raw materials. This all-in-one IFR integrating three functional elements (carbon, acid, and gas source) showed more efficient flame retardancy and excellent smoke suppression as well as better mechanical properties than the conventional APP. The incorporation of 22.5 wt.% MAPP into polypropylene (PP) eliminated the melt dripping phenomenon and passed the UL-94 V-0 rating. The results of the cone calorimetry test (CCT) revealed that the release of heat, smoke, and CO is significantly decreased, demonstrating that this novel IFR endows PP with excellent fire safety more effectively. For PP/MAPP composites, a possible IFR mechanism was proposed based on the analysis of the pyrolysis gas and char residues.
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17
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Bakry AM, Awad FS, Bobb JA, Ibrahim AA, El-Shall MS. Melamine-based functionalized graphene oxide and zirconium phosphate for high performance removal of mercury and lead ions from water. RSC Adv 2020; 10:37883-37897. [PMID: 35515170 PMCID: PMC9057240 DOI: 10.1039/d0ra07546a] [Citation(s) in RCA: 12] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/02/2020] [Accepted: 10/05/2020] [Indexed: 01/30/2023] Open
Abstract
Heavy metal ions are highly toxic and widely spread as environmental pollutants. This work reports the development of two novel chelating adsorbents, based on the chemical modifications of graphene oxide and zirconium phosphate by functionalization with melamine-based chelating ligands for the effective and selective extraction of Hg(ii) and Pb(ii) from contaminated water sources. The first adsorbent melamine, thiourea-partially reduced graphene oxide (MT-PRGO) combines the heavier donor atom sulfur with the amine and triazine nitrogen's functional groups attached to the partially reduced GO nanosheets to effectively capture Hg(ii) ions from water. The MT-PRGO adsorbent shows high efficiency for the extraction of Hg(ii) with a capacity of 651 mg g-1 and very fast kinetics resulting in a 100% removal of Hg(ii) from 500 ppb and 50 ppm concentrations in 15 second and 30 min, respectively. The second adsorbent, melamine zirconium phosphate (M-ZrP), is designed to combine the amine and triazine nitrogen's functional groups of melamine with the hydroxyl active sites of zirconium phosphate to effectively capture Pb(ii) ions from water. The M-ZrP adsorbent shows exceptionally high adsorption affinity for Pb(ii) with a capacity of 681 mg g-1 and 1000 mg g-1 using an adsorbent dose of 1 g L-1 and 2 g L-1, respectively. The high adsorption capacity is also coupled with fast kinetics where the equilibrium time required for the 100% removal of Pb(ii) from 1 ppm, 100 ppm and 1000 ppm concentrations is 40 seconds, 5 min and 30 min, respectively using an adsorbent dose of 1 g L-1. In a mixture of six heavy metal ions at a concentration of 10 ppm, the removal efficiency is 100% for Pb(ii), 99% for Hg(ii), Cd(ii) and Zn(ii), 94% for Cu(ii), and 90% for Ni(ii) while at a higher concentration of 250 ppm the removal efficiency for Pb(ii) is 95% compared to 23% for Hg(ii) and less than 10% for the other ions. Because of the fast adsorption kinetics, high removal capacity, excellent regeneration, stability and reusability, the MT-PRGO and M-ZrP are proposed as top performing remediation adsorbents for the solid phase extraction of Hg(ii) and Pb(ii), respectively from contaminated water.
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Affiliation(s)
- Ayyob M Bakry
- Department of Chemistry, Virginia Commonwealth University Richmond VA 23284 USA +1-804-828-8599 +1-804-828-2753
- Department of Chemistry, Faculty of Science, Jazan University Jazan 45142 Saudi Arabia
| | - Fathi S Awad
- Department of Chemistry, Virginia Commonwealth University Richmond VA 23284 USA +1-804-828-8599 +1-804-828-2753
- Chemistry Department, Faculty of Science, Mansoura University Mansoura 35516 Egypt
| | - Julian A Bobb
- Department of Chemistry, Virginia Commonwealth University Richmond VA 23284 USA +1-804-828-8599 +1-804-828-2753
| | - Amr A Ibrahim
- Department of Chemistry, Virginia Commonwealth University Richmond VA 23284 USA +1-804-828-8599 +1-804-828-2753
- Chemistry Department, Faculty of Science, Mansoura University Mansoura 35516 Egypt
| | - M Samy El-Shall
- Department of Chemistry, Virginia Commonwealth University Richmond VA 23284 USA +1-804-828-8599 +1-804-828-2753
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18
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Chuang C, Wu C, Wu K, Sheen H. Flame retardancy of water‐based intumescent coatings with etherified melamine–formaldehyde and polyvinyl acetate copolymer hybrid resin. J Appl Polym Sci 2020. [DOI: 10.1002/app.49279] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
Affiliation(s)
- Chih‐Shen Chuang
- Institute of Applied MechanicsNational Taiwan University Taipei Taiwan
| | - Chieh‐Ying Wu
- Institute of Applied MechanicsNational Taiwan University Taipei Taiwan
| | - Kuang‐Chong Wu
- Institute of Applied MechanicsNational Taiwan University Taipei Taiwan
| | - Horn‐Jiunn Sheen
- Institute of Applied MechanicsNational Taiwan University Taipei Taiwan
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19
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Liao H, Liu Y, Lin S. Exploitation of acetalization process of poly(vinyl alcohol) for the formation of crosslinked poly(vinyl formal) foams. POLYM ENG SCI 2020. [DOI: 10.1002/pen.25449] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
Affiliation(s)
- Honghui Liao
- The State Key Laboratory of Polymer Materials EngineeringPolymer Research Institute of Sichuan University Chengdu Sichuan People's Republic of China
| | - Yuan Liu
- The State Key Laboratory of Polymer Materials EngineeringPolymer Research Institute of Sichuan University Chengdu Sichuan People's Republic of China
| | - Shudong Lin
- Guangzhou Institute of ChemistryChinese Academy of Sciences Guangzhou People's Republic of China
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20
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Seidi F, Movahedifar E, Naderi G, Akbari V, Ducos F, Shamsi R, Vahabi H, Saeb MR. Flame Retardant Polypropylenes: A Review. Polymers (Basel) 2020; 12:polym12081701. [PMID: 32751298 PMCID: PMC7464193 DOI: 10.3390/polym12081701] [Citation(s) in RCA: 16] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/08/2020] [Revised: 07/27/2020] [Accepted: 07/28/2020] [Indexed: 11/16/2022] Open
Abstract
Polypropylene (PP) is a commodity plastic known for high rigidity and crystallinity, which is suitable for a wide range of applications. However, high flammability of PP has always been noticed by users as a constraint; therefore, a variety of additives has been examined to make PP flame-retardant. In this work, research papers on the flame retardancy of PP have been comprehensively reviewed, classified in terms of flame retardancy, and evaluated based on the universal dimensionless criterion of Flame Retardancy Index (FRI). The classification of additives of well-known families, i.e., phosphorus-based, nitrogen-based, mineral, carbon-based, bio-based, and hybrid flame retardants composed of two or more additives, was reflected in FRI mirror calculated from cone calorimetry data, whatever heat flux and sample thickness in a given series of samples. PP composites were categorized in terms of flame retardancy performance as Poor, Good, or Excellent cases. It also attempted to correlate other criteria like UL-94 and limiting oxygen index (LOI) with FRI values, giving a broad view of flame retardancy performance of PP composites. The collected data and the conclusions presented in this survey should help researchers working in the field to select the best additives among possibilities for making the PP sufficiently flame-retardant for advanced applications.
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Affiliation(s)
- Farzad Seidi
- Provincial Key Lab of Pulp and Paper Science and Technology and Joint International Research Lab of Lignocellulosic Functional Materials, Nanjing Forestry University, Nanjing 210037, China;
| | - Elnaz Movahedifar
- Department of Polymer Processing, Iran Polymer and Petrochemical Institute, Tehran 14965/115, Iran; (E.M.); (G.N.)
| | - Ghasem Naderi
- Department of Polymer Processing, Iran Polymer and Petrochemical Institute, Tehran 14965/115, Iran; (E.M.); (G.N.)
| | - Vahideh Akbari
- Université de Lorraine, CentraleSupélec, LMOPS, F-57000 Metz, France;
| | - Franck Ducos
- Université de Lorraine, IUT de Moselle Est, IUTSGM, 57600 Forbach, France;
| | - Ramin Shamsi
- Research and Development Center, Marun Petrochemical Company, Mahshahr 63531 69311, Iran;
| | - Henri Vahabi
- Université de Lorraine, CentraleSupélec, LMOPS, F-57000 Metz, France;
- Correspondence: (H.V.); or (M.R.S.); Tel.: +33-(0)38-793-9186 (H.V.); +98-912-826-4307 (M.R.S.); Fax: +33-(0)38-793-9101 (H.V.)
| | - Mohammad Reza Saeb
- Université de Lorraine, CentraleSupélec, LMOPS, F-57000 Metz, France;
- Correspondence: (H.V.); or (M.R.S.); Tel.: +33-(0)38-793-9186 (H.V.); +98-912-826-4307 (M.R.S.); Fax: +33-(0)38-793-9101 (H.V.)
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21
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Selective ultrasonic assisted synthesis of iron oxide mesoporous structures based on sulfonated melamine formaldehyde and survey of nanorod/sphere, sphere and core/shell on their catalysts properties for the Biginelli reaction. MATERIALS SCIENCE & ENGINEERING. C, MATERIALS FOR BIOLOGICAL APPLICATIONS 2019; 104:109975. [PMID: 31500037 DOI: 10.1016/j.msec.2019.109975] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/03/2018] [Revised: 07/08/2019] [Accepted: 07/13/2019] [Indexed: 11/22/2022]
Abstract
Sulfonated melamine-formaldehyde including iron oxide nanoparticles were synthesized by sulfonation of melamine-formaldehyde and then Fe3O4 nanoparticles were bounded onto the surface of sulfonated melamine-formaldehyde (SMF). Two different iron oxide nanostructures including nanorods/spheres and nanospheres on sulfonated melamine-formaldehyde (SMF/Fe3O4) were obtained only by modifying the time of radiation from 4 to 8 h in our synthetic method. Furthermore core/shell (Fe3O4@SMF) was prepared by entrapping Fe3O4 magnetic nanoparticles as the core and sulfonated melamine-formaldehyde as the outer shell. The prepared components were characterized via, Fourier transform infrared spectroscopy (FT-IR), titration, X-ray diffraction (XRD), scanning electron microscope (SEM), transmission electron microscopy (TEM), Brunauer-Emmett-Teller (BET) analysis, Barret-Joyner-Halenda (BJH) analysis, vibrating sample magnetometer (VSM), energy-dispersive X-ray (EDX) spectroscopy, and thermal gravimetric analysis (TGA). According to obtained results, the synthesized products had a thermal stability near 180 °C, particle-size distribution around of 20-140 nm and surface area between 6 and 10 m2/g. In this study, vapor was used as a heat source. These effective and magnetically recoverable catalysts were employed for the synthesis of numerous 3,4-dihydropyrimidin-2(1H)-ones by utilizing aldehydes, ethylacetoacetate and urea. Functional easiness, excellent yields, short reaction time, the simplicity of work-up or filter, and thermal stability of these catalysts created them as appropriate heterogeneous systems and acceptable alternative to different heterogeneous catalysts.
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22
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Preparation and characterization of a microencapsulated flame retardant and its flame-retardant mechanism in unsaturated polyester resins. POWDER TECHNOL 2019. [DOI: 10.1016/j.powtec.2019.05.077] [Citation(s) in RCA: 33] [Impact Index Per Article: 6.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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23
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Yu S, Xiao S, Zhao Z, Huo X, Wei J. Microencapsulated ammonium polyphosphate by polyurethane with segment of dipentaerythritol and its application in flame retardant polypropylene. Chin J Chem Eng 2019. [DOI: 10.1016/j.cjche.2019.04.023] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/02/2023]
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24
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Weems AC, Carrow JK, Gaharwar AK, Maitland DJ. Improving the Oxidative Stability of Shape Memory Polyurethanes Containing Tertiary Amines by the Presence of Isocyanurate Triols. Macromolecules 2018. [DOI: 10.1021/acs.macromol.8b01925] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/19/2023]
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25
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Simple synthesis of core-shell structure of Co–Co3O4 @ carbon-nanotube-incorporated nitrogen-doped carbon for high-performance supercapacitor. Electrochim Acta 2018. [DOI: 10.1016/j.electacta.2017.12.184] [Citation(s) in RCA: 143] [Impact Index Per Article: 23.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/10/2023]
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26
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Chen MJ, Wang X, Li XL, Liu XY, Zhong L, Wang HZ, Liu ZG. The synergistic effect of cuprous oxide on an intumescent flame-retardant epoxy resin system. RSC Adv 2017. [DOI: 10.1039/c7ra05482c] [Citation(s) in RCA: 25] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
Abstract
Neat epoxy resin (EP) is a highly flammable material, and the pyrolysis volatiles of it contain some harmful gases such as carbon monoxide, aromatic compounds, hydrocarbons, etc.
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Affiliation(s)
- Ming-Jun Chen
- School of Science (Sichuan)
- Xihua University
- Chengdu 610039
- China
| | - Xu Wang
- School of Science (Sichuan)
- Xihua University
- Chengdu 610039
- China
| | - Xin-Lei Li
- School of Science (Sichuan)
- Xihua University
- Chengdu 610039
- China
| | - Xing-Ya Liu
- School of Science (Sichuan)
- Xihua University
- Chengdu 610039
- China
| | - Liu Zhong
- School of Science (Sichuan)
- Xihua University
- Chengdu 610039
- China
| | - Hui-Zhen Wang
- School of Science (Sichuan)
- Xihua University
- Chengdu 610039
- China
| | - Zhi-Guo Liu
- School of Science (Sichuan)
- Xihua University
- Chengdu 610039
- China
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27
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Xie H, Lai X, Li H, Zeng X. Synthesis of a novel macromolecular charring agent with free-radical quenching capability and its synergism in flame retardant polypropylene. Polym Degrad Stab 2016. [DOI: 10.1016/j.polymdegradstab.2016.05.029] [Citation(s) in RCA: 59] [Impact Index Per Article: 7.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
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28
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Jiang T, Liu C, Liu L, Hong J, Dong M, Deng X. Synergistic flame retardant properties of a layered double hydroxide in combination with zirconium phosphonate in polypropylene. RSC Adv 2016. [DOI: 10.1039/c6ra15542a] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
Abstract
High-performance flame retardant nanocomposites were prepared for polypropylene (PP).
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Affiliation(s)
- Ting Jiang
- College of Chemistry and Chemical Engineering
- Southwest University
- Chongqing 400715
- P. R. China
| | - Changhua Liu
- College of Chemistry and Chemical Engineering
- Southwest University
- Chongqing 400715
- P. R. China
| | - Li Liu
- College of Chemistry and Chemical Engineering
- Southwest University
- Chongqing 400715
- P. R. China
| | - Jing Hong
- College of Chemistry and Chemical Engineering
- Southwest University
- Chongqing 400715
- P. R. China
| | - Ming Dong
- College of Chemistry and Chemical Engineering
- Southwest University
- Chongqing 400715
- P. R. China
| | - Xi Deng
- College of Chemistry and Chemical Engineering
- Southwest University
- Chongqing 400715
- P. R. China
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29
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Huang P, Pang Y, Zhang L, Wu F, Zhang S, Zheng W. A new approach designed for improving flame retardancy of intumescent polypropylene via continuous extrusion with supercritical CO2. RSC Adv 2016. [DOI: 10.1039/c6ra23909a] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
Abstract
scCO2-aided IFR dispersion of PP/IFR composites and their improved flame retardancy.
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Affiliation(s)
- Pengke Huang
- Ningbo Key Laboratory of Polymer Materials
- Polymers and Composites Division
- Ningbo Institute of Materials Technology and Engineering
- Chinese Academy of Sciences
- Ningbo
| | - Yongyan Pang
- Ningbo Key Laboratory of Polymer Materials
- Polymers and Composites Division
- Ningbo Institute of Materials Technology and Engineering
- Chinese Academy of Sciences
- Ningbo
| | - Lihua Zhang
- Ningbo Key Laboratory of Polymer Materials
- Polymers and Composites Division
- Ningbo Institute of Materials Technology and Engineering
- Chinese Academy of Sciences
- Ningbo
| | - Fei Wu
- Ningbo Key Laboratory of Polymer Materials
- Polymers and Composites Division
- Ningbo Institute of Materials Technology and Engineering
- Chinese Academy of Sciences
- Ningbo
| | - Shuhai Zhang
- School of Chemical and Environmental Engineering
- North University of China
- Taiyuan
- China
| | - Wenge Zheng
- Ningbo Key Laboratory of Polymer Materials
- Polymers and Composites Division
- Ningbo Institute of Materials Technology and Engineering
- Chinese Academy of Sciences
- Ningbo
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