【摘要】 以3,3’,4,4’-联苯四酸二酐(BPDA)和含咪唑环的芳香族二胺,2-(4-氨基苯基)-5-氨基苯并咪唑(4-APBI)或2-(3-氨基苯基)-5-氨基苯并咪唑(3-APBI)为聚合单体,以八(氨基苯基)聚倍半硅氧烷(OAPS)为交联剂,采用超临界CO2干燥工艺制备了两种PI气凝胶,PIA-1(BPDA/4-APBI/OAPS)与PIA-2(BPDA/3-APBI/OAPS)。研究表明,制备的PI气凝胶具有纳米串珠状的微观结构,其泡孔最可几孔径分别为22nm(PIA-1)与14 nm(PIA-2)。PIA-1与PIA-2的密度分别为0.105和0.080 g/cm3,BET表面积分别为693和302 m2/g。此外,制备的PI气凝胶具有良好的柔韧性与耐热稳定性,T g超过了350℃,T5d超过了530℃。更多还原

【Abstract】 Two kinds of polyimide( PI) aerogels,PIA-1( BPDA /4-APBI /OAPS) and PIA-2( BPDA /3-APBI / OAPS) have been successfully prepared via the supercritical carbon dioxide drying process of the PI gels derived from 3,3’,4,4’-biphenylene tetracarboxylic dianhydride( BPDA),2-( 4-aminophenyl)-5-aminobenzimidazole( 4-APBI) or 2-( 3-aminophenyl)-5-aminobenzimidazole( 3-APBI) and octa( aminophenyl) silsesquioxane( OAPS). The obtained PI aerogels exhibited micromorphology of a strain of beads with the pore size distribution peaks of 22 nm for PIA-1 and 14 nm for PIA-2. The densities of the PI aerogels are 0. 105 g / cm3for PIA-1 and 0. 080 g / cm3for PIA-2; and the Branuaer-Emmet-Teller( BET) surface areas of the aerogels are 693 m2/ g and 302 m2/ g,respectively. In addition,the PI aerogels exhibited good flexibility and thermal resistance with the T g higher than 350℃ and initial thermal decomposition temperatures over 530℃.更多还原