Abstract

The influence of nanosized cerium oxide as an active filler on the mechanical properties and thermal stability indices and heat resistance of films of thermally stable aromatic polyimides of various chemical structures is studied. It is shown that, depending on the polyimide structure the introduction of cerium oxide nanoparticles into the film can lead to a noticeable increase or a significant decrease in the thermal stability of the material during thermo-oxidative degradation. It is found that the thermal stability of the films increases significantly when polyimides containing sulfonic groups in elementary units serve as matrix polymers. The introduction of cerium oxide nanoparticles into such polyimides leads to an increase in the thermal stability of the films in air by 20–40°C. Moreover, in an inert medium the thermal stability indices for the films of matrix polymers and nanocomposites differ slightly. For all the studied polyimides, the introduction of cerium oxide does not cause a noticeable change in the glass transition temperature but in some cases leads to limitation of the compliance of the films in the temperature range above the glass transition.

中文翻译：

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纳米氧化铈对芳族聚酰亚胺薄膜热学性能的影响

摘要

研究了纳米氧化铈作为活性填料对各种化学结构的热稳定芳族聚酰亚胺薄膜的力学性能，热稳定性指标和耐热性的影响。已表明，根据聚酰亚胺的结构，将氧化铈纳米颗粒引入薄膜中可导致在热氧化降解过程中材料的热稳定性显着增加或显着降低。发现当在基本单元中含有磺酸基的聚酰亚胺用作基质聚合物时，膜的热稳定性显着提高。将氧化铈纳米颗粒引入此类聚酰亚胺中会导致薄膜在空气中的热稳定性提高20–40°C。此外，在惰性介质中，基质聚合物和纳米复合材料薄膜的热稳定性指数略有不同。对于所有研究的聚酰亚胺，氧化铈的引入不会引起玻璃化转变温度的明显变化，但是在某些情况下，会限制玻璃化转变温度以上温度范围内薄膜的柔韧性。