Curing and thermal properties of copolymer epoxy resins prepared by copolymerized bisphenol-A and epichlorohydrin with liquefied Dendrocalamus latiflorus

Dendrocalamus latiflorus Munro (ma bamboo) was liquefied in phenol or in polyethylene glycol/glycerol cosolvent, with H2SO4 as a catalyst. The liquefied bamboo was reacted with bisphenol-A and epichlorohydrin to prepare copolymer epoxy resins. The thermal properties of resins during and after curing were investigated by differential scanning calorimetry (DSC) and dynamic mechanical analysis (DMA). The results showed that a novel epoxy resin can be prepared by copolymerizing liquefied bamboo with bisphenol-A and epichlorohydrin in a two-step process. DSC analysis showed that the copolymer epoxy resins prepared with phenol-liquefied bamboo had a curing behavior similar to that of neat epoxy resin, even when 50% of the bisphenol-A was replaced with liquefied bamboo. However, the reactivity of copolymer epoxy resins prepared with polyhydric alcohol-liquefied bamboo decreased as the substitution amount of liquefied bamboo increased. DMA showed that the storage modulus and tan δ of cured copolymer epoxy resins decreased as the amount of substituted liquefied bamboo increased.