乙炔基封端聚酰亚胺增韧改性的相结构

以双酚A二醚二酐(BPADA)和3乙-炔苯胺(APA)为原料,通过两步法合成一种热固性可交联的聚酰亚胺预聚体.将此预聚体分别与不同结构的热塑性聚酰亚胺(PI)共混,对其进行增韧改性,通过调控热塑性聚酰亚胺的质量分数,引入结构相似且含有更多柔性基团的热塑性聚酰亚胺(如含有醚键和对称甲基结构的二酐),得到了热固/热塑性聚酰亚胺复合膜.利用差示扫描量热仪(DSC)及扫描电镜(SEM)对该体系的相分离结构和相容性进行研究,并讨论其机械性能和热性能.结果表明,相分离结构使体系的机械性能得到改善,同时也保持了原有的优异热性能.

Phase Structure Study of Toughening Ethynyl-capped Polyimide

Thermosetting cross-linked polyimide(PI) prepolymer was synthesized from 4,4′-bisphenol A dianhydride(BPADA) and 3-aminophenylacetylene(APA) through a two-step polycondensation, modified by thermoplastic polyimides with different structures to form polymer blends. By regulating the quantity of thermoplastic polyimide, thermoplastic resins with similer structure and more flexible groups such as ether and symmetric methyl structures were introduced to the thermosetting/thermoplastic polyimide composite membranes. Differential scanning calorimeter(DSC) and scanning electron microscopy(SEM) were taken to evaluate the phase separation structure and compatibility of the system. The mechanical and thermal properties were also discussed. The results show that phase separation structure improve the mechanical properties of the mixture without sacrificing the excellent thermal stability of the original resin system.