Cargando…
Thermal and Fire Behavior of a Bio-Based Epoxy/Silica Hybrid Cured with Methyl Nadic Anhydride
Thermosetting polymers have been widely used in many industrial applications as adhesives, coatings and laminated materials, among others. Recently, bisphenol A (BPA) has been banned as raw material for polymeric products, due to its harmful impact on human health. On the other hand, the use of arom...
Autores principales: | , , , , , , , , |
---|---|
Formato: | Online Artículo Texto |
Lenguaje: | English |
Publicado: |
MDPI
2020
|
Materias: | |
Acceso en línea: | https://www.ncbi.nlm.nih.gov/pmc/articles/PMC7466172/ https://www.ncbi.nlm.nih.gov/pubmed/32722585 http://dx.doi.org/10.3390/polym12081661 |
_version_ | 1783577751132831744 |
---|---|
author | Bifulco, Aurelio Marotta, Angela Passaro, Jessica Costantini, Aniello Cerruti, Pierfrancesco Gentile, Gennaro Ambrogi, Veronica Malucelli, Giulio Branda, Francesco |
author_facet | Bifulco, Aurelio Marotta, Angela Passaro, Jessica Costantini, Aniello Cerruti, Pierfrancesco Gentile, Gennaro Ambrogi, Veronica Malucelli, Giulio Branda, Francesco |
author_sort | Bifulco, Aurelio |
collection | PubMed |
description | Thermosetting polymers have been widely used in many industrial applications as adhesives, coatings and laminated materials, among others. Recently, bisphenol A (BPA) has been banned as raw material for polymeric products, due to its harmful impact on human health. On the other hand, the use of aromatic amines as curing agents confers excellent thermal, mechanical and flame retardant properties to the final product, although they are toxic and subject to governmental restrictions. In this context, sugar-derived diepoxy monomers and anhydrides represent a sustainable greener alternative to BPA and aromatic amines. Herein, we report an “in-situ” sol–gel synthesis, using as precursors tetraethylorthosilicate (TEOS) and aminopropyl triethoxysilane (APTS) to obtain bio-based epoxy/silica composites; in a first step, the APTS was left to react with 2,5-bis[(oxyran-2-ylmethoxy)methyl]furan (BOMF) or diglycidyl ether of bisphenol A (DGEBA)monomers, and silica particles were generated in the epoxy in a second step; both systems were cured with methyl nadic anhydride (MNA). Morphological investigation of the composites through transmission electron microscopy (TEM) demonstrated that the hybrid strategy allows a very fine distribution of silica nanoparticles (at nanometric level) to be achieved within a hybrid network structure for both the diepoxy monomers. Concerning the fire behavior, as assessed in vertical flame spread tests, the use of anhydride curing agent prevented melt dripping phenomena and provided high char-forming character to the bio-based epoxy systems and their phenyl analog. In addition, forced combustion tests showed that the use of anhydride hardener instead of aliphatic polyamine results in a remarkable decrease of heat release rate. An overall decrease of the smoke parameters, which is highly desirable in a context of greater fire safety was observed in the case of BOMF/MNA system. The experimental results suggest that the effect of silica nanoparticles on fire behavior appears to be related to their dispersion degree. |
format | Online Article Text |
id | pubmed-7466172 |
institution | National Center for Biotechnology Information |
language | English |
publishDate | 2020 |
publisher | MDPI |
record_format | MEDLINE/PubMed |
spelling | pubmed-74661722020-09-14 Thermal and Fire Behavior of a Bio-Based Epoxy/Silica Hybrid Cured with Methyl Nadic Anhydride Bifulco, Aurelio Marotta, Angela Passaro, Jessica Costantini, Aniello Cerruti, Pierfrancesco Gentile, Gennaro Ambrogi, Veronica Malucelli, Giulio Branda, Francesco Polymers (Basel) Article Thermosetting polymers have been widely used in many industrial applications as adhesives, coatings and laminated materials, among others. Recently, bisphenol A (BPA) has been banned as raw material for polymeric products, due to its harmful impact on human health. On the other hand, the use of aromatic amines as curing agents confers excellent thermal, mechanical and flame retardant properties to the final product, although they are toxic and subject to governmental restrictions. In this context, sugar-derived diepoxy monomers and anhydrides represent a sustainable greener alternative to BPA and aromatic amines. Herein, we report an “in-situ” sol–gel synthesis, using as precursors tetraethylorthosilicate (TEOS) and aminopropyl triethoxysilane (APTS) to obtain bio-based epoxy/silica composites; in a first step, the APTS was left to react with 2,5-bis[(oxyran-2-ylmethoxy)methyl]furan (BOMF) or diglycidyl ether of bisphenol A (DGEBA)monomers, and silica particles were generated in the epoxy in a second step; both systems were cured with methyl nadic anhydride (MNA). Morphological investigation of the composites through transmission electron microscopy (TEM) demonstrated that the hybrid strategy allows a very fine distribution of silica nanoparticles (at nanometric level) to be achieved within a hybrid network structure for both the diepoxy monomers. Concerning the fire behavior, as assessed in vertical flame spread tests, the use of anhydride curing agent prevented melt dripping phenomena and provided high char-forming character to the bio-based epoxy systems and their phenyl analog. In addition, forced combustion tests showed that the use of anhydride hardener instead of aliphatic polyamine results in a remarkable decrease of heat release rate. An overall decrease of the smoke parameters, which is highly desirable in a context of greater fire safety was observed in the case of BOMF/MNA system. The experimental results suggest that the effect of silica nanoparticles on fire behavior appears to be related to their dispersion degree. MDPI 2020-07-26 /pmc/articles/PMC7466172/ /pubmed/32722585 http://dx.doi.org/10.3390/polym12081661 Text en © 2020 by the authors. Licensee MDPI, Basel, Switzerland. This article is an open access article distributed under the terms and conditions of the Creative Commons Attribution (CC BY) license (http://creativecommons.org/licenses/by/4.0/). |
spellingShingle | Article Bifulco, Aurelio Marotta, Angela Passaro, Jessica Costantini, Aniello Cerruti, Pierfrancesco Gentile, Gennaro Ambrogi, Veronica Malucelli, Giulio Branda, Francesco Thermal and Fire Behavior of a Bio-Based Epoxy/Silica Hybrid Cured with Methyl Nadic Anhydride |
title | Thermal and Fire Behavior of a Bio-Based Epoxy/Silica Hybrid Cured with Methyl Nadic Anhydride |
title_full | Thermal and Fire Behavior of a Bio-Based Epoxy/Silica Hybrid Cured with Methyl Nadic Anhydride |
title_fullStr | Thermal and Fire Behavior of a Bio-Based Epoxy/Silica Hybrid Cured with Methyl Nadic Anhydride |
title_full_unstemmed | Thermal and Fire Behavior of a Bio-Based Epoxy/Silica Hybrid Cured with Methyl Nadic Anhydride |
title_short | Thermal and Fire Behavior of a Bio-Based Epoxy/Silica Hybrid Cured with Methyl Nadic Anhydride |
title_sort | thermal and fire behavior of a bio-based epoxy/silica hybrid cured with methyl nadic anhydride |
topic | Article |
url | https://www.ncbi.nlm.nih.gov/pmc/articles/PMC7466172/ https://www.ncbi.nlm.nih.gov/pubmed/32722585 http://dx.doi.org/10.3390/polym12081661 |
work_keys_str_mv | AT bifulcoaurelio thermalandfirebehaviorofabiobasedepoxysilicahybridcuredwithmethylnadicanhydride AT marottaangela thermalandfirebehaviorofabiobasedepoxysilicahybridcuredwithmethylnadicanhydride AT passarojessica thermalandfirebehaviorofabiobasedepoxysilicahybridcuredwithmethylnadicanhydride AT costantinianiello thermalandfirebehaviorofabiobasedepoxysilicahybridcuredwithmethylnadicanhydride AT cerrutipierfrancesco thermalandfirebehaviorofabiobasedepoxysilicahybridcuredwithmethylnadicanhydride AT gentilegennaro thermalandfirebehaviorofabiobasedepoxysilicahybridcuredwithmethylnadicanhydride AT ambrogiveronica thermalandfirebehaviorofabiobasedepoxysilicahybridcuredwithmethylnadicanhydride AT malucelligiulio thermalandfirebehaviorofabiobasedepoxysilicahybridcuredwithmethylnadicanhydride AT brandafrancesco thermalandfirebehaviorofabiobasedepoxysilicahybridcuredwithmethylnadicanhydride |