端硅氧烷基聚氨酯/环氧树脂复合材料形态及热力学性能研究

Morphologies and Thermal Properties of Alkoxysilane Terminated Polyurethane/Epoxy Resin Composites

用两种不同类型的低聚物二元醇与小分子硅烷偶联剂三乙氧硅丙基异氰酸酯(ICPTES)为原料,合成了不同结构的端硅氧烷基聚氨酯低聚物(PUSi):聚四氢呋喃醚二元醇型(PTSi)和聚己内酯二元醇型(PLSi),以此低聚物改性环氧树脂。通过Sol-gel技术及胺类固化剂与环氧基团的反应,得到了端硅氧烷基聚氨酯低聚物(PUSi)/环氧树脂(EP)复合体系。用FTIR表征了两种低聚物的化学结构;用扫描电镜(SEM)、动态力学性能测试(DMTA)及热重分析(TGA),研究了PLSi/PTSi含量对PUSi/EP复合体系的微观形态、热力学性能的影响。结果表明,PUSi在体系中形成了海岛结构,PLSi的加入改善了体系的相容性,当PLSi/PTSi的含量比为1∶1时,复合体系的5%热失重温度相比纯环氧树脂提高了近100℃,达275℃。

Two kinds of alkoxysilane terminated urethane oligomers（PUSi）,polytetramethyleneoxide glycol（PTMEG） urethane oligomer（PTSi） and polycaprolactone（PCL） urethane oligomer（PLSi）,were directly synthesized via reacting diols of PTMEG and PCL with isocyanatopropyltriethoxysilane（ICPTES）,respectively.PUSi/epoxy composites were prepared via sol-gel process and the reaction of amine curing agent and epoxy resin.The structure of PTSi and PLSi were characterized by FTIR.The morphology and thermal properties of the composites with different ratio of PLSi and PTSi were investigated with SEM,DMTA and TGA analysis.The results showed that a ＂sea-island＂ phase structure was formed in PUSi/ epoxy composites,and that the compatibility between PUSi and epoxy was improved with adding PLSi.And also,when the mass ratio of PLSi and PTSi was 1∶1,the PUSi/epoxy system had a highest temperature value at 5% mass loss,reaching to 275℃,an increase of 100℃ when compared with that of neat amine-cured epoxy resin.