以混合芳胺为固化剂,通过聚氨酯(Pu)对4,5-环氧环己烷-1,2-二甲酸二缩水甘油酯(TDE-85)与二酚基丙烷缩水甘油醚(E-51)环氧树脂的混合树脂体系的改性,制备了高性能聚氨酯改性环氧树脂(PU/EP)。通过红外光谱图、扫描电镜(SEM)、热重(TG)分析及力学性能的表征讨论PU/EP体系的结构与性能特征。研究结果表明:PU和EP分子链之间存在着化学接枝反应,能有效地改善PU/EP体系中PU和EP分子间的相容性及相互贯穿;与TDE-85与E-51的混和环氧树脂比,PU改性TDE-85与E-51的混和环氧树脂仍然具有很强的耐热性能,并且冲击强度、拉伸强度均获得显著提高;PU/EP体系断口裂纹呈明显的韧性断裂特征,说明TDE-85与E-51的混和环氧树脂PU改性增韧效果明显。
With polyurethane(PU) modification of the epoxy resin (EP) blend of phenol-based epoxy propane (E-51) and diglycidyl-4, 5-epoxycyclohexane-1, 2-dicarboxylate (TDE-85), the modified epoxy resin system(PU/EP) was formed using mixed aromatic amine as curing agent. The structure characteristics of the PU/EP system were analyzed by IR and SEM. The mechanical properties of the modified material were tested, and the thermal stability of the modified EP blend was also investigated by TG. The results indicate that the graft copolymerization between PU and EP effectly inforces the miscibility of the PU/EP system. Compared with the properties of pure EP, the impact strength and tensile strength of the PU/EP with high thermal stability are markedly enhanced, and the fracture surface of the PU/EP system displays tough fracture features.