生物基环氧固化剂的制备及其固化性能研究

Research on the preparation and curing properties of bio-based epoxy curing agent

采用乳酸和丁二酸酐为原料通过熔融聚合制备了端羧基聚乳酸(HOOC-PLA),以其和马来酸酐(MAH)在引发剂作用下通过溶液回流的方法制备了生物基环氧固化剂(HOOC-PLA-g-MAH)。采用傅里叶红外光谱,示差热扫描量热仪,动态热机械分析仪及拉力实验机等对环氧树脂固化物的结构和性能进行了表征。结果表明:环氧树脂/HOOC-PLA-g-MAH/2,4,6-三(二甲胺基甲基)苯酚(DMP-30)体系在质量比为1:0.4:0.01,90℃/4 h+110℃/1 h条件下可完全固化。固化物弯曲强度和拉伸强度分别为150 MPa和65.1 MPa,Tg为106℃,力学性能和热稳定性能较好。

The carboxyl terminated lactic acid prepolymer （HOOC-PLA）was synthesized through melt polymerization with L-lactic acid and succine anhydride. The bio-based epoxy curing agent （HOOC-PLA-g-MAH）was obtained by solvent reflux method with （HOOC-PLA） and maleic anhydride （MAH） in the role of initiator. The structures and properties of cured epoxy resin were charac- terized by FTIR,DSC,dynamic DMA and universal mechanical testing machine. The results indicated that the epoxy resins were completely cured at 90 ℃ for 4 h and post-curing at 110 ℃ for 1 h as the mass ratio of epoxy resin ,HOOC-PLA-g-MAH and tris （dimethylaminomethyl） phenol （DMP-30） was 1 ： 0.4 ： 0.01. The impact strength and flexural strength of cured resins with Ts = 106 ℃ were 65.1 MPa and 150 MPa, respectively. The cured product had good mechanical properties and thermal stabilities.