Synthesis of epoxy resins from alcohol‐liquefied wood and the mechanical properties of the cured resins

Abstract

Abstract New wood‐based epoxy resins were synthesized from alcohol‐liquefied wood. Wood was first liquefied by the reaction with polyethylene glycol and glycerin. The alcohol‐liquefied wood with plenty of hydroxyl groups were precursors for synthesizing the wood‐based epoxy resins. Namely, the alcoholic OH groups of the liquefied wood reacted with epichlorohydrin under alkali condition with a phase transfer catalyst, so that the epoxy groups were put in the liquefied wood. The wood‐based epoxy resins and the alcohol‐based epoxy resins as reference materials were cured with polyamide amine. The glass transition temperature (Tg), the tensile strength, and the modulus of elasticity of the wood‐based epoxy resin were higher than those of the alcohol‐based epoxy resin. Also, the shear adhesive strength of the wood‐based epoxy resin to steel plates was higher than those of the alcohol‐based epoxy resins, which was equivalent to the level of petroleum‐based bisphenol‐A type epoxy resins. The higher Tg of the wood‐based epoxy resin than that of the alcohol‐based epoxy resin is one of the evidences that the wood‐derived molecules were chemically incorporated into the network structures. © 2010 Wiley Periodicals, Inc. J Appl Polym Sci, 2011