Zhao Xinfu, Su Mengqing, Yu Shimo, Zhang Jing, Liu Xiaochan, Qiu Kang, Yi Xibin, Zhang Jian, Dou Guoliang, Wang Mengdi
Shandong Provincial Key Laboratory of Special Silicone-Containing Materials, Advanced Materials Institute, QiLu University of Technology (Shandong Academy of Sciences), Jinan 250014, P. R. China.
Shandong Copolymer Silicone Technology Research Institute, Weifang 261000, P. R. China.
ACS Appl Mater Interfaces. 2024 Jun 5;16(22):29282-29290. doi: 10.1021/acsami.4c05455. Epub 2024 May 23.
Polyimide (PI) aerogel is a good thermal insulation material with the highest temperature resistance in practical application. But the mechanical strength of PI aerogels prepared by freeze-drying or thermoimide methods is weak. In this research, TPU was selected as an aging solution to solve the problem of the low mechanical strength of PI aerogel prepared by the freeze-drying method. Previous work has certified that the coupling of PI and thermoplastic polyurethane (TPU) can enhance the mechanical strength of PI aerogel to a certain extent due to the flexibility of TPU. But excessive TPU will change the PI structure in the cross-linking process and decrease the mechanical strength of the aerogel. Thus, a new kind of PI gel modification method was provided by using TPU as an aging solution, and the mechanical strength of PI aerogel is improved to 3.06 MPa. Furthermore, the shrinkage, specific surface area, waterproof angle, and thermal conductivity all show good performance, thus enabling PI aerogel to be used in many aspects. Specially, the method is simple and can be used to prepare some other high-strength aerogels.
聚酰亚胺（PI）气凝胶是一种在实际应用中具有最高耐温性的良好隔热材料。但通过冷冻干燥或热酰亚胺化方法制备的PI气凝胶机械强度较弱。在本研究中，选择热塑性聚氨酯（TPU）作为老化溶液来解决通过冷冻干燥法制备的PI气凝胶机械强度低的问题。先前的工作已经证实，由于TPU的柔韧性，PI与热塑性聚氨酯（TPU）的偶联可以在一定程度上提高PI气凝胶的机械强度。但过量的TPU会在交联过程中改变PI结构并降低气凝胶的机械强度。因此，通过使用TPU作为老化溶液提供了一种新型的PI凝胶改性方法，PI气凝胶的机械强度提高到3.06MPa。此外，收缩率、比表面积、防水角和热导率均表现出良好的性能，从而使PI气凝胶能够在许多方面得到应用。特别地，该方法简单，可用于制备其他一些高强度气凝胶。
