WOOD-BASED EPOXY RESINS AND THE RAMIE FIBER REINFORCED COMPOSITES

Wood-based epoxy resin was synthesized from resorcinol-liquefied wood. First, wood components were depolymerized and liquefied by reaction with resorcinol. The resorcinol-liquefied wood with plenty of hydroxyl groups could be considered as a precursor for synthesizing wood-based epoxy resin. Namely, the phenolic-OH groups of the liquefied wood reacted with epichlorohydrine under alkali condition. By the glycidyl etherification, epoxy functionality was introduced to the liquefied wood. The wood-based epoxy resin was cured with 4, 4'-diamino diphenyl sulphone (DDS) and the thermal and mechanical properties were evaluated. The flexural modulus and strength of the cured wood-based epoxy resin were comparable to those of the petroleum-based bisphenol-A type epoxy resin (diglycidyl ether of bisphenol-A: DGEBA). The mechanical and adhesive properties of the wood-based epoxy resins suited well for matrix resins of fiber reinforced composites. Therefore, biomass composites consist of ramie fibers and the wood-based epoxy resin were fabricated. The flexural modulus and strength of the biomass composites were equivalent to those of the same fiber reinforced bisphenol-A type epoxy composites.