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Pawlak M, Pobłocki K, Drzeżdżon J, Gawdzik B, Jacewicz D. "Isocyanates and isocyanides - life-threatening toxins or essential compounds?". THE SCIENCE OF THE TOTAL ENVIRONMENT 2024; 934:173250. [PMID: 38761928 DOI: 10.1016/j.scitotenv.2024.173250] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/24/2023] [Revised: 04/14/2024] [Accepted: 05/12/2024] [Indexed: 05/20/2024]
Abstract
Isocyanides and isocyanates are some of the most reactive compounds in organic chemistry, making them perceived as compounds with high potential for use in both the laboratory and industry. With their high reactivity also comes several disadvantages, most notably their potentially high toxicity. The following article is a collection of information on the toxic effects of the isocyanide group on the human body and the environment. Information on the mechanism of how these harmful substances affect living tissues and the environment, worldwide information on how to protect against these chemicals, current regulations, and exposure limits for specific countries is compiled. The latest research on the application uses of isocyanates and isocyanides is also outlined, as well as the latest safer and greener methods and techniques to work with these compounds. Additionally, the presented article can serve as a brief guide to the organic toxicity of a group of isocyanates and isocyanates.
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Affiliation(s)
- Marta Pawlak
- Faculty of Chemistry, Department of Environmental Technology, University of Gdansk, Wita Stwosza 63, Gdansk, Poland.
| | - Kacper Pobłocki
- Faculty of Chemistry, Department of Environmental Technology, University of Gdansk, Wita Stwosza 63, Gdansk, Poland
| | - Joanna Drzeżdżon
- Faculty of Chemistry, Department of Environmental Technology, University of Gdansk, Wita Stwosza 63, Gdansk, Poland
| | - Barbara Gawdzik
- Institute of Chemistry, Jan Kochanowski University, Uniwersytecka 7, 25-406 Kielce, Poland
| | - Dagmara Jacewicz
- Faculty of Chemistry, Department of Environmental Technology, University of Gdansk, Wita Stwosza 63, Gdansk, Poland.
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2
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Hong SM, Kwon HJ, Sun JM, Lee CW. Synthesis and Characteristic Valuation of a Thermoplastic Polyurethane Electrode Binder for In-Mold Coating. Polymers (Basel) 2024; 16:375. [PMID: 38337264 DOI: 10.3390/polym16030375] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/03/2024] [Revised: 01/22/2024] [Accepted: 01/27/2024] [Indexed: 02/12/2024] Open
Abstract
A polyurethane series (PHEI-PU) was prepared via a one-shot bulk polymerization method using hexamethylene diisocyanate (HDI), polycarbonate diol (PCD), and isosorbide derivatives (ISBD) as chain extenders. The mechanical properties were evaluated using a universal testing machine (UTM), and the thermal properties were evaluated using thermogravimetric analysis (TGA) and differential scanning calorimetry (DSC). The PHEI-PU series exhibited excellent mechanical properties with an average tensile strength of 44.71 MPa and an elongation at break of 190%. To verify the applicability of different proportions of PU as an electrode binder, PU and Ag flakes were mixed (30/70 wt%) and coated on PCT substrates, the electrodes were evaluated by four-point probe before and after 50% elongation, and the dispersion was evaluated by scanning electron microscopy (SEM). The electrical resistance change rate of PHEI-PU series was less than 20%, and a coating layer with well-dispersed silver flakes was confirmed even after stretching. Therefore, it exhibited excellent physical properties, heat resistance, and electrical resistance change rate, confirming its applicability as an electrode binder for in-mold coating.
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Affiliation(s)
- Suk-Min Hong
- Department of Chemistry, College of Science and Technology, Dankook University, Cheonan 31116, Republic of Korea
| | - Hyuck-Jin Kwon
- Department of Chemistry, College of Science and Technology, Dankook University, Cheonan 31116, Republic of Korea
| | - Jung-Min Sun
- Department of Chemistry, College of Science and Technology, Dankook University, Cheonan 31116, Republic of Korea
| | - Chil Won Lee
- Department of Chemistry, College of Science and Technology, Dankook University, Cheonan 31116, Republic of Korea
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3
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De Hoyos-Martinez PL, Mendez SB, Martinez EC, Wang DY, Labidi J. Elaboration of Thermally Performing Polyurethane Foams, Based on Biopolyols, with Thermal Insulating Applications. Polymers (Basel) 2024; 16:258. [PMID: 38257057 PMCID: PMC10821512 DOI: 10.3390/polym16020258] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/20/2023] [Revised: 12/30/2023] [Accepted: 01/09/2024] [Indexed: 01/24/2024] Open
Abstract
In this work, biobased rigid polyurethane foams (PUFs) were developed with the aim of achieving thermal and fireproofing properties that can compete with those of the commercially available products. First, the synthesis of a biopolyol from a wood residue by means of a scaled-up process with suitable yield and reaction conditions was carried out. This biopolyol was able to substitute completely the synthetic polyols that are typically employed within a polyurethane formulation. Different formulations were developed to assess the effect of two flame retardants, namely, polyhedral oligomeric silsesquioxane (POSS) and amino polyphosphate (APP), in terms of their thermal properties and degradation and their fireproofing mechanism. The structure and the thermal degradation of the different formulations was evaluated via Fourier Transformed Infrared Spectroscopy (FTIR) and thermogravimetric analysis (TGA). Likewise, the performance of the different PUF formulations was studied and compared to that of an industrial PUF. From these results, it can be highlighted that the addition of the flame retardants into the formulation showed an improvement in the results of the UL-94 vertical burning test and the LOI. Moreover, the fireproofing performance of the biobased formulations was comparable to that of the industrial one. In addition to that, it can be remarked that the biobased formulations displayed an excellent performance as thermal insulators (0.02371-0.02149 W·m-1·K-1), which was even slightly higher than that of the industrial one.
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Affiliation(s)
- Pedro Luis De Hoyos-Martinez
- Chemical and Environmental Engineering Department, University of the Basque Country, Plaza Europa 1, 20018 Donostia-San Sebastián, Spain;
| | - Sebastian Barriga Mendez
- Chemical and Environmental Engineering Department, University of the Basque Country, Plaza Europa 1, 20018 Donostia-San Sebastián, Spain;
| | - Eriz Corro Martinez
- Chemical and Environmental Engineering Department, University of the Basque Country, Otaola Etorbidea 29, 20600 Eibar, Spain;
| | - De-Yi Wang
- IMDEA Materials Institute, C/Eric Kandel, 2, 28906 Getafe, Spain;
- Escuela Politécnica Superior, Universidad Francisco de Vitoria, Ctra. Pozuelo-Majadahonda Km 1800, 28223 Pozuelo de Alarcón, Spain
| | - Jalel Labidi
- Chemical and Environmental Engineering Department, University of the Basque Country, Plaza Europa 1, 20018 Donostia-San Sebastián, Spain;
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Masri M, Haberal M. Establishing a Solid-Organ Transplant Registry in MESOT Countries. EXP CLIN TRANSPLANT 2024; 22:1-13. [PMID: 38385367 DOI: 10.6002/ect.mesot2023.l6] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/23/2024]
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Loureiro MV, Aguiar A, dos Santos RG, Bordado JC, Pinho I, Marques AC. Design of Experiment for Optimizing Microencapsulation by the Solvent Evaporation Technique. Polymers (Basel) 2023; 16:111. [PMID: 38201776 PMCID: PMC10780531 DOI: 10.3390/polym16010111] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/02/2023] [Revised: 12/22/2023] [Accepted: 12/25/2023] [Indexed: 01/12/2024] Open
Abstract
We employed microemulsion combined with the solvent evaporation technique to produce biodegradable polycaprolactone (PCL) MCs, containing encapsulated isophorone diisocyanate (IPDI), to act as crosslinkers in high-performance adhesive formulations. The MC production process was optimized by applying a design of experiment (DoE) statistical approach, aimed at decreasing the MCs' average size. For that, three different factors were considered, namely the concentration of two emulsifiers, polyvinyl alcohol (PVA) and gum arabic (GA); and the oil-to-water phase ratio of the emulsion. The significance of each factor was evaluated, and a predictive model was developed. We were able to decrease the average MC size from 326 μm to 70 µm, maintaining a high encapsulation yield of approximately 60% of the MCs' weight, and a very satisfactory shelf life. The MCs' average size optimization enabled us to obtain an improved distributive and dispersive mixture of isocyanate-loaded MCs at the adhesive bond. The MCs' suitability as crosslinkers for footwear adhesives was assessed following industry standards. Peel tests revealed peel strength values above the minimum required for casual footwear, while the creep test results indicated an effective crosslinking of the adhesive. These results confirm the ability of the MCs to release IPDI during the adhesion process and act as crosslinkers for new adhesive formulations.
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Affiliation(s)
- Mónica V. Loureiro
- CERENA—Centro de Recursos Naturais e Ambiente, Departamento de Engenharia Química, Instituto Superior Técnico, Universidade de Lisboa, Avenida Rovisco Pais, 1049-001 Lisbon, Portugal; (A.A.); (R.G.d.S.); (J.C.B.)
| | - António Aguiar
- CERENA—Centro de Recursos Naturais e Ambiente, Departamento de Engenharia Química, Instituto Superior Técnico, Universidade de Lisboa, Avenida Rovisco Pais, 1049-001 Lisbon, Portugal; (A.A.); (R.G.d.S.); (J.C.B.)
| | - Rui G. dos Santos
- CERENA—Centro de Recursos Naturais e Ambiente, Departamento de Engenharia Química, Instituto Superior Técnico, Universidade de Lisboa, Avenida Rovisco Pais, 1049-001 Lisbon, Portugal; (A.A.); (R.G.d.S.); (J.C.B.)
| | - João C. Bordado
- CERENA—Centro de Recursos Naturais e Ambiente, Departamento de Engenharia Química, Instituto Superior Técnico, Universidade de Lisboa, Avenida Rovisco Pais, 1049-001 Lisbon, Portugal; (A.A.); (R.G.d.S.); (J.C.B.)
| | - Isabel Pinho
- CIPADE—Indústria e Investigação de Produtos Adesivos, SA. Av. Primeiro de Maio 121, 3700-227 São João da Madeira, Portugal;
| | - Ana C. Marques
- CERENA—Centro de Recursos Naturais e Ambiente, Departamento de Engenharia Química, Instituto Superior Técnico, Universidade de Lisboa, Avenida Rovisco Pais, 1049-001 Lisbon, Portugal; (A.A.); (R.G.d.S.); (J.C.B.)
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Rusen E, Toader G, Diacon A, Dîrloman FM, Matache LC, Alexe F, Dinescu A, Mocanu A. Synthesis and Mechanical Performances of Polyurethane Bio-Based Adhesives Resulted from the Depolymerization of Lignocellulose Biomass. ACS OMEGA 2023; 8:38178-38190. [PMID: 37867717 PMCID: PMC10586253 DOI: 10.1021/acsomega.3c04393] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 06/20/2023] [Accepted: 08/30/2023] [Indexed: 10/24/2023]
Abstract
The purpose of this study is to valorize biomass waste into products with added value for indoor applications. Thus, broadleaf sawdust was chemically processed by the solvolysis reaction in acid catalysis in the presence of diethylene glycol at 160 °C for 4 h. After filtration and removal of the unreacted biomass, the glycolysis product was used in 6 different polyurethane adhesive formulations for wood bonding. The adhesive films were characterized by FT-IR, TGA, and DMA, while the mechanical performances were investigated by tensile and three-point bending tests. An innovative method for the determination of the working time was proposed. After the displacement of the wood substrates by the tensile test, the bonded area was investigated by SEM analysis. To confirm a correlation between the mechanical performances of the adhesives and their structure/formulation, two-dimensional (2D) simulations were performed based on the tensile tests.
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Affiliation(s)
- Edina Rusen
- Faculty
of Chemical Engineering and Biotechnologies, University Politehnica of Bucharest, 1-7 Gh. Polizu Street, 011061 Bucharest, Romania
| | - Gabriela Toader
- Military
Technical Academy “Ferdinand I”, 39-49 George Cosbuc Avenue, 050141 Bucharest, Romania
| | - Aurel Diacon
- Faculty
of Chemical Engineering and Biotechnologies, University Politehnica of Bucharest, 1-7 Gh. Polizu Street, 011061 Bucharest, Romania
- Military
Technical Academy “Ferdinand I”, 39-49 George Cosbuc Avenue, 050141 Bucharest, Romania
| | - Florin Marian Dîrloman
- Military
Technical Academy “Ferdinand I”, 39-49 George Cosbuc Avenue, 050141 Bucharest, Romania
| | - Liviu Cristian Matache
- Military
Technical Academy “Ferdinand I”, 39-49 George Cosbuc Avenue, 050141 Bucharest, Romania
| | - Florentina Alexe
- Research
and Innovation Center for CBRN Defense and Ecology, 225 Oltenitei, 041327 Bucharest, Romania
| | - Adrian Dinescu
- National
Institute for Research and Development in Microtechnologies—IMT
Bucharest, 126A Erou
Iancu Nicolae Street, 077190 Bucharest, Romania
| | - Alexandra Mocanu
- Faculty
of Chemical Engineering and Biotechnologies, University Politehnica of Bucharest, 1-7 Gh. Polizu Street, 011061 Bucharest, Romania
- National
Institute for Research and Development in Microtechnologies—IMT
Bucharest, 126A Erou
Iancu Nicolae Street, 077190 Bucharest, Romania
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Hernández-Ramos F, Alriols MG, Antxustegi MM, Labidi J, Erdocia X. Valorisation of crude glycerol in the production of liquefied lignin bio-polyols for polyurethane formulations. Int J Biol Macromol 2023; 247:125855. [PMID: 37460069 DOI: 10.1016/j.ijbiomac.2023.125855] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/24/2023] [Revised: 06/26/2023] [Accepted: 07/14/2023] [Indexed: 07/23/2023]
Abstract
Bio-polyols, produced by liquefying lignin with polyhydric alcohols, offer a promising alternative to conventional polyols for polyurethane production. To enhance the sustainability on the production of these bio-polyols, this study proposes the use of crude glycerol and microwave-assisted liquefaction as substitutes for conventional methods and commercial glycerol. This approach reduces the energy requirements of the reaction while also adding value to this by-product. The synthesis of bio-polyols with suitable properties to produce elastic and rigid polyurethane was carried out using previously optimised reaction conditions. Organosolv lignins obtained from Eucalyptus globulus and Pinus radiata were employed, using polyethylene glycol and crude glycerol as solvents and sulphuric acid as a catalyst. Several parameters of the bio-polyols were analysed, including hydroxyl number (IOH), acid number (An), and functionality (f), suggesting that the bio-polyols were suitable for polyurethane synthesis. Bio-polyols formulated to produce rigid polyurethanes exhibited IOH values of 554 and 383 (mg KOH/g), An values of 1.91 and 4.21 (mg KOH/g), and functionalities of 4.16 and 3.14 for Eucalyptus globulus and Pinus radiata lignin. In the case of bio-polyols for elastic polyurethanes, the values were 228 and 173 (mg KOH/g) (IOH), 20.94 and 25.09 (mg KOH/g) (An), and functionalities of 3.51 and 2.08.
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Affiliation(s)
- Fabio Hernández-Ramos
- Biorefinery Processes Research Group (BioRP), Chemical and Environmental Engineering Department, University of the Basque Country (UPV/EHU), Plaza Europa 1, 20018 San Sebastian, Spain.
| | - María González Alriols
- Biorefinery Processes Research Group (BioRP), Chemical and Environmental Engineering Department, University of the Basque Country (UPV/EHU), Plaza Europa 1, 20018 San Sebastian, Spain
| | - M Mirari Antxustegi
- Biorefinery Processes Research Group (BioRP), Chemical and Environmental Engineering Department, University of the Basque Country (UPV/EHU), Avda. Otaola 29, 20600 Eibar, Spain
| | - Jalel Labidi
- Biorefinery Processes Research Group (BioRP), Chemical and Environmental Engineering Department, University of the Basque Country (UPV/EHU), Plaza Europa 1, 20018 San Sebastian, Spain
| | - Xabier Erdocia
- Biorefinery Processes Research Group (BioRP), Department of Applied Mathematics, University of the Basque Country (UPV/EHU), Rafael Moreno "Pichichi" 3, Bilbao 48013, Spain
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Silva TAR, Marques AC, Dos Santos RG, Shakoor RA, Taryba M, Montemor MF. Development of BioPolyurethane Coatings from Biomass-Derived Alkylphenol Polyols-A Green Alternative. Polymers (Basel) 2023; 15:polym15112561. [PMID: 37299359 DOI: 10.3390/polym15112561] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/19/2023] [Revised: 05/30/2023] [Accepted: 05/31/2023] [Indexed: 06/12/2023] Open
Abstract
Bio-based polyols were obtained from the thermochemical liquefaction of two biomass feedstocks, pinewood and Stipa tenacissima, with conversion rates varying between 71.9 and 79.3 wt.%, and comprehensively characterized. They exhibit phenolic and aliphatic moieties displaying hydroxyl (OH) functional groups, as confirmed by attenuated total reflectance-Fourier transform infrared spectroscopy (ATR-FTIR) and nuclear magnetic resonance spectroscopy (NMR) analysis. The biopolyols obtained were successfully employed as a green raw material to produce bio-based polyurethane (BioPU) coatings on carbon steel substrates, using, as an isocyanate source, a commercial bio-based polyisocyanate-Desmodur® Eco N7300. The BioPU coatings were analyzed in terms of chemical structure, the extent of the reaction of the isocyanate species, thermal stability, hydrophobicity, and adhesion strength. They show moderate thermal stability at temperatures up to 100 °C, and a mild hydrophobicity, displaying contact angles between 68° and 86°. The adhesion tests reveal similar pull-off strength values (ca. 2.2 MPa) for the BioPU either prepared with pinewood and Stipa-derived biopolyols (BPUI and BPUII). Electrochemical impedance spectroscopy (EIS) measurements were carried out on the coated substrates for 60 days in 0.05 M NaCl solution. Good corrosion protection properties were achieved for the coatings, with particular emphasis on the coating prepared with the pinewood-derived polyol, which exhibited a low-frequency impedance modulus normalized for the coating thickness of 6.1 × 1010 Ω cm at the end of the 60 days test, three times higher than for coatings prepared with Stipa-derived biopolyols. The produced BioPU formulations show great potential for application as coatings, and for further modification with bio-based fillers and corrosion inhibitors.
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Affiliation(s)
- Tiago A R Silva
- Centro de Química Estrutural (CQE), Institute of Molecular Sciences (IMS), Departamento de Engenharia Química (DEQ), Instituto Superior Técnico (IST), Universidade de Lisboa, Av. Rovisco Pais 1, 1049-001 Lisboa, Portugal
| | - Ana C Marques
- Centro de Recursos Naturais e Ambiente (CERENA), Departamento de Engenharia Química (DEQ), Instituto Superior Técnico, Universidade de Lisboa, Av. Rovisco Pais 1, 1049-001 Lisboa, Portugal
| | - Rui G Dos Santos
- Centro de Recursos Naturais e Ambiente (CERENA), Departamento de Engenharia Química (DEQ), Instituto Superior Técnico, Universidade de Lisboa, Av. Rovisco Pais 1, 1049-001 Lisboa, Portugal
| | - Rana A Shakoor
- Centre for Advanced Materials (CAM), Qatar University, 9FHQ + JMF, Doha P.O. Box 2713, Qatar
| | - Maryna Taryba
- Centro de Química Estrutural (CQE), Institute of Molecular Sciences (IMS), Departamento de Engenharia Química (DEQ), Instituto Superior Técnico (IST), Universidade de Lisboa, Av. Rovisco Pais 1, 1049-001 Lisboa, Portugal
| | - Maria Fátima Montemor
- Centro de Química Estrutural (CQE), Institute of Molecular Sciences (IMS), Departamento de Engenharia Química (DEQ), Instituto Superior Técnico (IST), Universidade de Lisboa, Av. Rovisco Pais 1, 1049-001 Lisboa, Portugal
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Jiang W, Adamopoulos S, Hosseinpourpia R, Walther T, Medved S. Properties and Emissions of Three-Layer Particleboards Manufactured with Mixtures of Wood Chips and Partially Liquefied Bark. MATERIALS (BASEL, SWITZERLAND) 2023; 16:1855. [PMID: 36902971 PMCID: PMC10004268 DOI: 10.3390/ma16051855] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 01/20/2023] [Revised: 02/14/2023] [Accepted: 02/21/2023] [Indexed: 06/18/2023]
Abstract
Partial liquefaction of residual biomass shows good potential for developing new materials suitable for making bio-based composites. Three-layer particleboards were produced by replacing virgin wood particles with partially liquefied bark (PLB) in the core or surface layers. PLB was prepared by the acid-catalyzed liquefaction of industrial bark residues in polyhydric alcohol. The chemical and microscopic structure of bark and residues after liquefaction were evaluated by means of Fourier Transform Infrared Spectroscopy (FTIR) and Scanning Electron Microscopy (SEM), while the particleboards were tested for their mechanical and water-related properties, as well as their emission profiles. Through a partial liquefaction process, some FTIR absorption peaks of the bark residues were lower than those of raw bark, indicating hydrolysis of chemical compounds. The surface morphology of bark did not change considerably after partial liquefaction. Particleboards with PLB in the core layers showed overall lower densities and mechanical properties (modulus of elasticity, modulus of rupture, and internal bond strength), and were less water-resistant as compared to the ones with PLB used in the surface layers. Formaldehyde emissions from the particleboards were 0.284-0.382 mg/m2·h, and thus, below the E1 class limit required by European Standard EN 13986:2004. The major emissions of volatile organic compounds (VOCs) were carboxylic acids as oxidization and degradation products from hemicelluloses and lignin. The application of PLB in three-layer particleboards is more challenging than in single-layer boards as PLB has different effects on the core and surface layers.
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Affiliation(s)
- Wen Jiang
- Department of Technical Physics, University of Eastern Finland, P.O. Box 1627, 70211 Kuopio, Finland
| | - Stergios Adamopoulos
- Department of Forest Biomaterials and Technology, Swedish University of Agricultural Sciences, Vallvägen 9C, 75007 Uppsala, Sweden
| | - Reza Hosseinpourpia
- Department of Forestry and Wood Technology, Linnaeus University, Lückligs Plats 1, 35195 Växjö, Sweden
- College of Forest Resources and Environmental Science, Michigan Technological University, Houghton, MI 49931, USA
| | - Thomas Walther
- Department of Forestry and Wood Technology, Linnaeus University, Lückligs Plats 1, 35195 Växjö, Sweden
- IKEA Industry AB, Skrivaregatan 5, 21532 Malmö, Sweden
| | - Sergej Medved
- Department of Wood Science and Technology, Biotechnical Faculty, University of Ljubljana, Rožna Dolina C VIII/34, SI-1000 Ljubljana, Slovenia
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Palle I, Lodin V, Mohd Yunus AA, Lee SH, Md Tahir P, Hori N, Antov P, Takemura A. Effects of NCO/OH Ratios on Bio-Based Polyurethane Film Properties Made from Acacia mangium Liquefied Wood. Polymers (Basel) 2023; 15:polym15051154. [PMID: 36904395 PMCID: PMC10007325 DOI: 10.3390/polym15051154] [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: 02/01/2023] [Revised: 02/22/2023] [Accepted: 02/23/2023] [Indexed: 03/02/2023] Open
Abstract
The compatibility between isocyanate and polyol plays an important role in determining a polyurethane product's performance. This study aims to evaluate the effect of varying the ratios between polymeric methylene diphenyl diisocyanate (pMDI) and Acacia mangium liquefied wood polyol on the polyurethane film properties. A. mangium wood sawdust was liquefied in polyethylene glycol/glycerol co-solvent with H2SO4 as a catalyst at 150 °C for 150 min. The A. mangium liquefied wood was mixed with pMDI with difference NCO/OH ratios to produce film through the casting method. The effects of the NCO/OH ratios on the molecular structure of the PU film were examined. The formation of urethane, which was located at 1730 cm-1, was confirmed via FTIR spectroscopy. The TGA and DMA results indicated that high NCO/OH ratios increased the degradation temperature and glass transition from 275 °C to 286 °C and 50 °C to 84 °C, respectively. The prolonged heat appeared to boost the crosslinking density of the A. mangium polyurethane films, which finally resulted in a low sol fraction. From the 2D-COS analysis, the hydrogen-bonded carbonyl (1710 cm-1) had the most significant intensity changes with the increasing NCO/OH ratios. The occurrence of the peak after 1730 cm-1 revealed that there was substantial formation of urethane hydrogen bonding between the hard (PMDI) and soft (polyol) segments as the NCO/OH ratios increased, which gave higher rigidity to the film.
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Affiliation(s)
- Ismawati Palle
- Faculty of Tropical Forestry, Universiti Malaysia Sabah, Jalan UMS, Kota Kinabalu 88400, Sabah, Malaysia
- Correspondence: (I.P.); (A.T.)
| | - Valeritta Lodin
- Faculty of Tropical Forestry, Universiti Malaysia Sabah, Jalan UMS, Kota Kinabalu 88400, Sabah, Malaysia
| | - Ag Ahmad Mohd Yunus
- Faculty of Tropical Forestry, Universiti Malaysia Sabah, Jalan UMS, Kota Kinabalu 88400, Sabah, Malaysia
| | - Seng Hua Lee
- Department of Wood Industry, Faculty of Applied Sciences, University Teknologi MARA (UiTM) Cawangan Pahang Kampus Jengka, Bandar Tun Razak 26400, Pahang, Malaysia
- Institute of Tropical Forestry and Forest Products, University Putra Malaysia, Serdang 43400, Selangor, Malaysia
| | - Paridah Md Tahir
- Institute of Tropical Forestry and Forest Products, University Putra Malaysia, Serdang 43400, Selangor, Malaysia
- Faculty of Forestry and Environment, University Putra Malaysia, Serdang 43400, Selangor, Malaysia
| | - Naruhito Hori
- Laboratory of Adhesive Sciences and Bio-Composites, Department of Biomaterial Sciences, Graduate School of Agricultural and Life Sciences, The University of Tokyo, 1-1-1 Yayoi, Bunkyo-Ku, Tokyo 113-8657, Japan
| | - Petar Antov
- Faculty of Forest Industry, University of Forestry, 1797 Sofia, Bulgaria
| | - Akio Takemura
- Laboratory of Adhesive Sciences and Bio-Composites, Department of Biomaterial Sciences, Graduate School of Agricultural and Life Sciences, The University of Tokyo, 1-1-1 Yayoi, Bunkyo-Ku, Tokyo 113-8657, Japan
- Correspondence: (I.P.); (A.T.)
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Berzins R, Merijs-Meri R, Zicans J. Comparison of Two-Component Silyl-Terminated Polyether/Epoxy Resin Model and Complete Systems and Evaluation of Their Mechanical, Rheological and Adhesive Properties. Polymers (Basel) 2022; 14:polym14122421. [PMID: 35745997 PMCID: PMC9230202 DOI: 10.3390/polym14122421] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/10/2022] [Revised: 06/07/2022] [Accepted: 06/13/2022] [Indexed: 02/04/2023] Open
Abstract
The current research is devoted to the investigation of the influence of a secondary amine compatibilizer and customized additive package on the tensile, rheological and adhesive properties of a Silyl-terminated polyether (SIL)/Epoxy resin (EP) model and completed two-component systems. A SIL/EP model and completed two-component systems were developed over a broad range of the both pre-polymer ratios (90/10-30/70 wt.-to-wt%). Additive packages of the components A and B were designed to prevent premature polycondensation of the respective pre-polymers (including suitable catalysts for each of the pre-polymers, as well as vinyltrimetoxysilane as a drying agent for moisture control), to ensure easy processing and stable performance of the system. Results of the investigation testify that the values of the tensile strength and Shore-A hardness of the compatibilized systems are higher in comparison to unmodified ones. In the presence of the additive package, a further improvement of tensile strength and tensile strain values is observed for SIL-rich compositions (SIL content above 70 wt%), whereas at lower SIL concentrations, the reinforcing effect is considerably reduced. In respects to adhesion properties, the highest values to a broad range of substrates with different surface polarities are observed at the SIL/EP range from 80/20 to 50/50 wt.-to-wt%.
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Recent Advances in Development of Waste-Based Polymer Materials: A Review. Polymers (Basel) 2022; 14:polym14051050. [PMID: 35267873 PMCID: PMC8914771 DOI: 10.3390/polym14051050] [Citation(s) in RCA: 10] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/24/2021] [Revised: 02/04/2022] [Accepted: 03/01/2022] [Indexed: 11/16/2022] Open
Abstract
Limited petroleum sources, suitable law regulations, and higher awareness within society has caused sustainable development of manufacturing and recycling of polymer blends and composites to be gaining increasing attention. This work aims to report recent advances in the manufacturing of environmentally friendly and low-cost polymer materials based on post-production and post-consumer wastes. Sustainable development of three groups of materials: wood polymer composites, polyurethane foams, and rubber recycling products were comprehensively described. Special attention was focused on examples of industrially applicable technologies developed in Poland over the last five years. Moreover, current trends and limitations in the future “green” development of waste-based polymer materials were also discussed.
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Tian F, Xu D, Xu X. Synergistic Effect of APP and TBC Fire-Retardants on the Physico-Mechanical Properties of Strandboard. MATERIALS 2022; 15:ma15020435. [PMID: 35057153 PMCID: PMC8777585 DOI: 10.3390/ma15020435] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 12/13/2021] [Revised: 01/04/2022] [Accepted: 01/04/2022] [Indexed: 12/23/2022]
Abstract
This study explored the feasibility of fabricating fire-retardant strandboard with low mechanical properties deterioration to the physico-mechanical properties. A hybrid fire-retardant system of ammonium polyphosphate (APP) and 1,3,5-tris(2,3-dibromopropyl)-1,3,5-triazinane-2,4,6-trione (TBC) was investigated. Thermogravimetric analysis results show that both APP and TBC enhance the thermal stability and incombustibility of wood strands. An infrared spectrum was applied to investigate the effect of flame retardants on the curing behaviors of polymeric diphenylmethane diisocyanate (PMDI) resin. Based on the results of limiting oxygen index (LOI) and Cone calorimetry (CONE), APP and TBC both lead to a higher fire retardancy to strandboard. It is worth mentioning that the two flame retardants lead to evidently differential influences on the modulus of rupture (MOR), modulus of elasticity (MOE), internal bond (IB), and water-soaking thickness swelling (TS) properties of strandboard. Hence, a hybrid flame retardant is prominent in manufacturing strandboard with both good fire retardant and satisfying physico-mechanical properties.
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Affiliation(s)
| | | | - Xinwu Xu
- Correspondence: ; Tel.: +86-13814097545
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