Low-density polyimide aerogel and preparation method thereof

• Main Authors: WANG JIANYING, HUANG YUHONG, PEI XINGQI, LI XIAOMIN, ZHU YONG, YAO ZENG, CHENG SILONG, ZHONG JIBIN
• Format: Patent
• Language: Chinese; English
• Published: 22.06.2016
• Subjects: AFTER-TREATMENT NOT COVERED BY SUBCLASSES C08B, C08C, C08F,C08G; CHEMISTRY; COMPOSITIONS BASED THEREON; COMPOSITIONS OF MACROMOLECULAR COMPOUNDS; GENERAL PROCESSES OF COMPOUNDING; MACROMOLECULAR COMPOUNDS OBTAINED OTHERWISE THAN BY REACTIONSONLY INVOLVING UNSATURATED CARBON-TO-CARBON BONDS; METALLURGY; ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; WORKING-UP

The invention provides low-density polyimide aerogel and a preparation method thereof. The preparation method includes preparing midbody, polyimide acid salt, dissolving the salt in the water to sufficiently expand according to a certain proportion, generating transparent and stable aerogel. The aerogel can be stored for a long time without significant degradation and is high in molecular weight, and product performance is excellent and stable. The aerogel is high in contraction performance through the vacuum drying process after freezing, and is low in density. In addition, the process of the method is low in device cost, safer and easy to control as compared with a super-critical drying method. The polyimide aerogel produced has low density and excellent comprehensive performance. 本发明提供一种低密度聚酰亚胺气凝胶及其制备方法。本发明的方法制备出中间体聚酰胺酸盐，该盐按一定比例溶于水中可充分溶胀，生成透明均一、结构稳定的水凝胶，长期存放不会明显降解，且分子量高，使产品性能优异且稳定；且该水凝胶经冷冻后真空干燥过程中抗收缩能力强，制得的气凝胶密度较低。另一方面，本发明的方法工艺过程比超临界干燥法设备成本低、工艺过程更安全且易于控制。而本发明制得的聚酰亚胺气凝胶具有较低的密度且综合性能优异。