均苯型聚酰亚胺模塑粉的制备与性能

用含有扭曲非共平面结构的二胺1,3-二(3-氨基苯氧基-4'-苯酰基 )苯(BABB)与均苯四甲酸二酐(PMDA)缩聚制备了具有3种不同分子量的均苯型热塑性聚酰亚胺模塑粉, 并研究了其组成、 聚集态结构、 熔体黏度、 稳定性和热性能, 将模塑粉模压成型后进行机械性能测试. 结果表明, 引入柔性的二胺, 模塑粉的玻璃化转变温度(T_g)与传统的均苯型聚酰亚胺相比明显下降, 熔体黏度大幅度下降, 且具有良好的熔体黏度稳定性. 同时, 均苯四甲酸酐的存在保证了该模塑粉具有优异的热稳定性和优异的机械性能及较低的吸水率.

Synthesis and Characterization of Polypyromelliticimide Polyimide Molding Powders

To improve the processability of the polyimide molding powder, a novel molding powder with twisted structure was prepared with 1,3-bisbenzene(BABB) and pyromellitic dianhydride(PMDA). The component, morphological structure, melt viscosity, thermal stability of molding powder and the mechanical properties of molding products were studied. The results show that the glass-transition temperature and melt viscosity of molding powder reduce markedly, compared with the traditional polyimides, because of the introduction of the flexible structures in polymer main chain. The polyimide molding powder exhibited excellent melt viscosity stability and thermal stability. The molding products also possessed outstanding mechanical properties and lower water absorption.