Effect of Low-temperature Imidization on Properties and Aggregation Structures of Polyimide Films with Different Rigidity  

作　　者：Yan Jia Lei Zhai Song Mo Yi Liu Li-Xin Liu Xin-Yu Du Min-Hui He Lin Fan 

机构地区：[1]Key Laboratory of Science and Technology on High-tech Polymer Materials,Institute of Chemistry,Chinese Academy of Sciences,Beijing 100190,China [2]School of Chemical Sciences,University of Chinese Academy of Sciences,Beijing 100049,China

出　　处：《Chinese Journal of Polymer Science》2024年第8期1134-1146,共13页高分子科学（英文版）

基　　金：financially supported by the National Key Research and Development Program of China(No.2022YFB3603105);Key Programs of the Chinese Academy of Sciences(No.ZDRW-CN-2023-3-2);the National Natural Science Foundation of China(No.51803221);Natural Science Foundation of Beijing Municipality(No.2202068)。

摘　　要：The traditional high-temperature preparation process of polyimide can cause many problems and limits the wider application in extreme conditions.An important challenge to be solved urgently is the reduction of imidization temperature.In this work,twelve kinds of polyimide films with different chain rigidity were prepared at low temperature of 200℃,in the absence or presence of imidazole used as the catalyst.The molecular rigidity and free volume were theoretically calculated,and relationship between structure and properties were systematically studied.The results show that imidization reaction under low temperatures is significantly affected by the rigidity of molecula r chains.The rigid structure of polyimide is not conducive to the low-temperature imidization,but this adverse effect can be eliminated by adding catalyst,resulting the notably increased imidization degree.The optical and thermal properties can be improved to a certain extent for the chemically catalyzed system,resulting in relatively higher heat resistance and thermal stability.While the mechanical performance could be determined by com plicating factors,greatly different from polyimide films prepa red by high temperature method.To investigate aggregation structures of film s,the effect of chain rigidity and catalyst on the stacking or orientation of molecular chains was further elaborated.This wo rk can contribute to the understanding of chemically catalyzed imidization that is rarely reported in the existing research,and will provide guidance for the low-temperature preparation of high-performance polyimides.

关 键 词：POLYIMIDE IMIDIZATION CATALYST Structure and properties Aggregation structures 

分 类 号：TQ323.7[化学工程—合成树脂塑料工业] TB383.2[一般工业技术—材料科学与工程]