有机气凝胶的超声法制备

Fabrication of organic aerogel by supersonic technique

在间苯二酚类有机气凝胶的制备工艺中引入超声波技术，缩短了有机气凝胶制备周期。实验发现：反应物质量分数为10％的溶液在超声作用下的凝胶时间减少8％～17％，超声波能有效抑制凝胶过程中的氧化作用。在反应初始阶段，通过激光粒度仪测量稀溶液反应，发现超声波作用下的凝胶核生长速度是普通加热的凝胶核生长速度的87倍左右。微量水分测定仪的数据表明，低强度超声波可以上万倍地加快凝胶样品的溶剂交换速率。

Supersonic technique was introduced into the synthetic route of resorcinol-formaldehyde（RF） aerogel to shorten the fabrication period. The effects of supersonic on gelating and solvent exchanging process were studied. The gelating time by supersonic was shorten by 8%-17 % in 10% RF solution. In diluted RF solution, the growth of gel nucleus by supersonic irradiation was about 87 times the velocity of that heating. Supersonic restrained the oxidation effect of reactant in the gelating process. Low intensity supersonic wave speeded up the water exchange by 10 000 times in the solvent exchanging process.