【摘要】 以相对廉价的多聚硅 (E - 4 0 )为硅源 ,通过溶胶 -凝胶工艺制备了SiO2 气凝胶 .采用以三甲基氯硅烷(TMCS)为表面修饰剂 ,硅油为干燥介质的表面修饰工艺 ,实现了在常压条件下的制备 .气凝胶热导率的测试采用的是瞬态热线法 ,同时还采用BET(brunaner emmett teller)方法 ,对气凝胶的孔径等特性进行了测试 ,系统研究了密度、温度、气压、湿度及掺杂物等因素对材料导热性能的影响 .更多还原

【Abstract】 Nano-porous SiO 2 aerogel insulations were prepared via sol-gel process from polyethoxydisiloxanes (E-40).The aerogels were dried at ambient pressure after surface modification of the alcogels.The pore size distribution of silica aerogels is from several nanometer to dozens of nanometer,which were determined by BET(brunaner-emmett-teller).The thermal conductivity measurement of the silica aerogels was determined using the transient hot-wire technique.The influence of density,temperature,pressure,humidity and doping to the thermal conductivity was studied.更多还原