Homopolyimides are prepared by 4,4′-(ethyne-1,2-diyl)diphthalic anhydride as dianhydride monomer and several diamine monomers. The copolyimides are prepared with 4,4′-oxydianiline as an amine monomer， 3,3′,4,4′-oxydiphthalic anhydride as an anhydride monomer with the addition of 4,4′-(ethyne-1,2-diyl)diphthalic anhydride as another anhydride monomer. The structure of polyimides is characterized by Fourier transform infrared spectroscopy and X-ray diffraction. Thermogravimetric analysis, thermomechanical analysis and thermo-oxidative degradation kinetics analysis are used to investigate the properties of polyimides. The homopolyimide show the best thermal stability in both nitrogen and air atmosphere by 4,4′-oxydianiline and 4,4′-(ethyne-1,2-diyl)diphthalic anhydride. The results also indicate that the thermally cross-linkable copolyimide films not only enhance the thermal stability behaviors of polyimide by controlling the addition of dianhydride, but also improve substantially the upper limit temperature of thermal aging by undergoing chemical cross-linking reaction of the diphenylethynylene structures and providing multifarious naphthalene ring groups and biphenyl structures. Diphenylacetylene crosslinking merging to the long-chain of polyimide is a useful conversion for enhancing the thermal stability and the thermal degradation stability of aromatic polymers.

均聚酰亚胺是由 4,4'-(ethyne-1,2-diyl)diphthalic anhydride 作为二酐单体和几种二胺单体制备的。共聚酰亚胺以 4,4'-氧二苯胺为胺单体，3,3',4,4'-氧二邻苯二甲酸酐为酸酐单体，加入 4,4'-(乙炔-1,2-二基)二邻苯二甲酸酐作为另一种酸酐单体。聚酰亚胺的结构通过傅里叶变换红外光谱和X射线衍射表征。热重分析、热机械分析和热氧化降解动力学分析用于研究聚酰亚胺的性能。均聚酰亚胺通过 4,4'-氧二苯胺和 4,4'-(乙炔-1,2-二基)二邻苯二甲酸酐在氮气和空气气氛中均表现出最佳的热稳定性。结果还表明，可热交联的共聚酰亚胺薄膜不仅通过控制二酐的加入来增强聚酰亚胺的热稳定性行为，而且通过发生二苯乙炔结构的化学交联反应，显着提高了热老化的上限温度。并提供多种多样的萘环基团和联苯结构。二苯乙炔交联合并到聚酰亚胺的长链上是提高芳族聚合物热稳定性和热降解稳定性的有用转化。同时通过二苯乙炔结构的化学交联反应，提供多种萘环基团和联苯结构，大大提高了热老化的上限温度。二苯乙炔交联合并到聚酰亚胺的长链上是提高芳族聚合物热稳定性和热降解稳定性的有用转化。同时通过二苯乙炔结构的化学交联反应，提供多种萘环基团和联苯结构，大大提高了热老化的上限温度。二苯乙炔交联合并到聚酰亚胺的长链上是提高芳族聚合物热稳定性和热降解稳定性的有用转化。