通过掺杂双酚环氧树脂来调控间苯二酚-甲醛(RF)气凝胶的微结构,在常压干燥条件下获得线收缩率较小的树脂基气凝胶。利用场发射扫描电子显微镜(FESEM)、N_2吸附-脱附比表面积与孔径分析仪等仪器对树脂基气凝胶的微观形貌、结构进行表征,用Hotdisk热分析仪测试热导率。结果表明:在常压干燥后,通过掺杂双酚环氧树脂,间苯二酚(R)与Na_2CO_3(C)催化剂的n(R)/n(C)值为500、间苯二酚占甲醛质量分数30%的RF树脂基气凝胶密度为0.42 g/cm~3,仍能维持较好的孔结构,比表面积为421.8 m~2/g,并且极大地降低了树脂基气凝胶的线收缩,线收缩率为1.5%。
The microstructure of resorcinol-formaldehyde( RF) aerogel was controlled by the doping of bisphenol epoxy resin. Resin matrix aerogel with tiny linear shrinkage rate was obtained by subcritical drying process. Field emission scanning electron microscopy( FESEM),surface area and pore size analyzer were used to investigate the microtopography and the microstructure of the resin-based aerogels.The thermal weight loss was analyzed by Hotdisk thermal analyzer. Results showed that with a trend to the theoretical value,the density of RF resin based aerogel doped with bisphenol epoxy resin was 0. 42 g / cm~3 after the drying under ambient conditions while resorcinol / sodium carbonate molar ratio was 500,and the mass fraction was 30%. Specific surface area of the resin based aerogel was 421. 8 m~2/ g, thus maintaining a good pore structure. The linear shrinkage of the aerogel was reduced with its linear shrinkage rate of 1. 5%.