摘要
以3,3′,4,4′-联苯四酸二酐（sBPDA）和2,2′-二甲基-4,4′-二氨基联苯胺（DMBZ）为聚合单体,八（氨基苯基）聚倍半硅氧烷（OAPS）为交联剂,SiO2纳米粒子为填料,采用超临界二氧化碳干燥工艺制备了一系列聚酰亚胺（PI）/SiO2纳米复合气凝胶（CPIA-SiO2-0~CPIA-SiO2-7）。研究表明：SiO2纳米粒子的引入对PI气凝胶的耐热性能未产生显著的影响。然而,随着SiO2纳米粒子含量的增加,PI气凝胶的孔隙率从89.6%逐渐降低至79.4%,BET表面积也随之从425.5m2/g降低至380.2m2/g,纳米泡孔孔径分布呈现出变宽的趋势。SiO2的引入显著提高了PI气凝胶的抗原子氧侵蚀能力,含量为7%（质量分数,下同）的PI/SiO2复合气凝胶CPIA-SiO2-7的原子氧侵蚀率（2.6%）仅为不含SiO2气凝胶CPIA-SiO2-0的原子氧侵蚀率（12.3%）的1/5左右。
A series of polyimide（PI）-SiO_2 nanocomposite aerogels（CPIA-SiO_2-0-CPIA-SiO_2-7）were successfully prepared viathe supercritical carbon dioxide drying process of the nanocomposite PI wet gels derived from 3,3′,4,4′-biphenylene tetracarboxylic dianhydride（BPDA）and 2,2′-dimethylbenzidine（DMBZ）with octa（aminophenyl）silsesquioxane（OAPS）as the end-capper,and nano-sized silica particles as the filler.The results indicate that the introduction of nanoscale silica particles have not apparently affected the thermal resistance of the obtained aerogels.However,with the increase of SiO_2 loading in the aerogels,the porosity from 89.6% to 79.4% and the Branuaer-Emmet-Teller（BET）surface areas of the composite aerogels decrease from 425.5m2/g to 380.2m2/g,meanwhile,the pore size distribution widens gradually.At last,the atomic-oxygen resistance of the PI-SiO_2 aerogels is greatly improved by introduction of nanoscale SiO_2 fillers.The atomic-oxygen erosion ratio（2.6%）of CPIA-SiO_2-7with 7% SiO_2 loading is only 1/5that（12.3%）of the pristine CPIA aerogel（CPIA-SiO_2-0）.
出处
《材料工程》
EI
CAS
CSCD
北大核心
2015年第12期17-23,共7页
Journal of Materials Engineering
基金
国家自然科学基金资助项目(51573094
51173188)
国家重点基础研究发展计划(973)资助项目(2014CB643605)
