title: Bio-based epoxy/chitin nanofiber composites cured with amine-type hardeners containing chitosan.
abstract: Sorbitol polyglycidyl ether (SPE) which is a bio-based water-soluble epoxy resin was cured with chitosan (CS) and/or a commercial water-soluble polyamidoamine- or polyetheramine-type epoxy hardener (PAA or PEA). Furthermore, biocomposites of the CS-cured SPE (CS-SPE) and CS/PAA- or CS/PEA-cured SPE (SPE-CA or SPE-CE) biocomposites with chitin nanofiber (CNF) were prepared by casting and compression molding methods, respectively. The curing reaction of epoxy and amino groups of the reactants was confirmed by the FT-IR spectral analysis. SPE-CS and SPE-CA were almost transparent films, while SPE-CE was opaque. Transparency of SPE-CS/CNF and SPE-CA/CNF became a little worse with increasing CNF content. The tanδ peak temperature of SPE-CS was higher than those of SPE-PAA and SPE-PEA. SPE-CA or SPE-CE exhibited two tanδ peak temperatures related to glass transitions of the CS-rich and PAA-rich or PEA-rich moieties. The tanδ peak temperatures related to the CS-rich and PAA-rich moieties increased with increasing CNF content. A higher order of tensile strengths and moduli of the cured resins was SPE-CS≫SPE-CA>SPE-CE. The tensile strength and modulus of each sample were much improved by the addition of 3wt% CNF, while further addition of CNF caused a lowering of the strength and modulus.
authors.affiliation: Department of Life and Environmental Sciences, Faculty of Engineering, Chiba Institute of Technology, Japan. Electronic address: mitsuhiro.shibata@p.chibakoudai.jp.
authors.forename: Mitsuhiro
authors.initials: M
authors.lastname: Shibata
authors.affiliation: Department of Life and Environmental Sciences, Faculty of Engineering, Chiba Institute of Technology, Japan.
authors.forename: Motohiro
authors.initials: M
authors.lastname: Enjoji
authors.affiliation: Department of Life and Environmental Sciences, Faculty of Engineering, Chiba Institute of Technology, Japan.
authors.forename: Katsumi
authors.initials: K
authors.lastname: Sakazume
authors.affiliation: Department of Chemistry and Biotechnology, Graduate School of Engineering, Tottori University, 4-101 Koyama-cho, Minami 680-8552, Tottori, Japan.
authors.forename: Shinsuke
authors.initials: S
authors.lastname: Ifuku
mesh_terms: D048271:Chitosan / Q000031:analogs & derivatives* / Q000138:chemical synthesis / Q000737:chemistry*; D004853:Epoxy Resins / Q000138:chemical synthesis / Q000737:chemistry*; D057139:Nanofibers / Q000737:chemistry*; D009757:Nylons / Q000737:chemistry; D017550:Spectroscopy, Fourier Transform Infrared; D013696:Temperature; D013718:Tensile Strength
chemical_list: D004853:Epoxy Resins; D009757:Nylons; D048271:Chitosan
keywords: Bio-based epoxy resin; Biocomposites; Chitin nanofiber; Chitosan; Sorbitol polyglycidyl ether