极性基团对环氧树脂基体力学性能及吸水特性的影响

摘要

Tensile, flexural and water resistance properties of four kinds of epoxy resin systems, I. e. CYD-128/THPA/DMP-30 (CTD), TDE-85/THPA/DMP-30 (TTD), CYD-128/IPDA (CI) and TDE-8S/IFDA (II) were investigated. The influences of die epoxy resin types, curing agent types and molecular structures on the properties of the epoxy matrixes were discussed. Hie results show that, cured with a same curing agent, TDE-85epoocy resin (with ester groups) system exhibits higher flexural strength and Young's modulus than CYD-128 (without ester groups) system. The brittleness order of the four epoxy matrixes is TI >TTD～CTD>CI. As CTD and CI have less content of polarity groups, such as ester and amine, seawater absorption of CTD and CI is smaller than that of TTD and TI. After seawater immersion, part of the ester groups hydrotyzes and the matrix becomes more brittle. As a result, the tensile and flexural strength of the matrixes are decreased significantly. CTD system recovers about 92% of the original tensile strength after drying processing.%研究了CYD- 128/THPA/DMP- 30 (CTD)、TDE- 85/THPA/DMP- 30(TTD)、CYD- 128/IPDA(CI)与TDE- 85/IPDA (TI)4种环氧树脂基体浇铸体的拉伸、弯曲和耐海水性能,分析了树脂、固化剂类型和分子结构对树脂基体性能的影响.结果表明,使用相同固化剂时,TDE-85树脂固化物的弯曲强度与杨氏模量高于CYD- 128树脂固化物;4种树脂基体脆性由大到小依次为:TI＞ TTD≈ CTD＞ CI; CTD与CI体系酯基、胺基等极性基团含量少,吸水率小于TTD与TI体系;人工海水浸泡后,酯基水解与树脂脆化导致树脂基体拉伸、弯曲强度严重衰减,只有CID体系拉伸强度在重新干燥后恢复率较高,达到原有强度的92％左右.