a-ODPA共聚的耐高温热塑性聚酰亚胺的研究

以2,3,3',4'-二苯醚四甲酸二酐(a-ODPA)为单体,与不同配比的4,4'-二氨基二苯醚(4,4'-ODA)和1,4-苯二胺(1,4-PDA)共聚,制备了一系列的聚酰亚胺(PI)。结果表明,随着1,4-PDA摩尔分数的增加,Tg(玻璃化转变温度)从279℃逐渐上升到328℃,同时比浓对数黏度从110 mL/g逐渐下降到40 mL/g(DMAc,25℃)。当1,4-PDA的摩尔分数不超过0.4的时候,该PI在DMAc、DMF、NMP、DMSO和γ-丁内酯中具有良好的溶解性,塑料样条在220℃的高温下,力学性能的保持率良好。

Study on High Temperature Resistant Thermoplastic Polyimide from a-ODPA

A series of polyimides were prepared by reacting different molar ratios of 4,4＇-oxydianiline（4,4＇-ODA）and 1,4-phenylenediamine（1,4-PDA） with 2,3,3′,4′-biphenyltetracarboxylic dianhydride（a-BPDA）. The results showed that with increasing the molar fraction of 1,4-PDA, the glass transition temperatures（Tg） ranged from 279 to 328 ℃, and the inherent viscosities in dimethylacetamide（DMAc） at 25 ℃ declined to 40 mL/g from 110 mL/g. When the molar fraction of 1,4-PDA was less than 0.4, the polyimides had good solubilities in DMAc, dimethylformamide（DMF）, Nmethyl-2-pyrrolidone（NMP） and γ-butyrrolactone. Meanwhile, the plastic samples maintained good mechanical performance even at 220 ℃.