Polyamides (PAs) based on terephthaloyl chloride and a series of aromatic diamines were synthesized; PA films were prepared by solution casting without mechanical stretching to produce high-performance films with good optical transparency and dimensional stability. The PA films displayed high heat resistance with glass transition temperatures (Tg) of 342–399°C. Good mechanical properties were obtained with tensile modulus and strength up to 5.38 GPa and 195.4 MPa, respectively. Coefficient of thermal expansion of the as-cast PA films achieved to an ultralow value of 8.3 ppm °C−1 and could be tailored in a wide range as a function of the macromolecular composition. The series of PA films showed a transparent and colorless feature, with the cutoff wavelength in the range of 355–365 nm. The data were discussed from the perspective of structure–property relationship, may give helpful knowledge for the topic of PA chemistry, and this method could provide an alternative for the production of high-performance colorless polymer films.

中文翻译：

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具有高耐热性和尺寸稳定性的无色聚酰胺薄膜的合成与性能

合成了基于对苯二甲酰氯和一系列芳香二胺的聚酰胺（PAs）；PA薄膜是通过溶液流延制备的，无需机械拉伸，以生产具有良好光学透明度和尺寸稳定性的高性能薄膜。PA 薄膜显示出高耐热性，玻璃化转变温度 (Tg) 为 342–399°C。获得了良好的机械性能，拉伸模量和强度分别高达 5.38 GPa 和 195.4 MPa。铸态 PA 薄膜的热膨胀系数达到 8.3 ppm °C-1 的超低值，并且可以根据大分子组成在很宽的范围内进行调整。该系列 PA 薄膜显示出透明无色的特性，截止波长范围为 355-365 nm。