%0 Journal Article
%T Effect of Heat Treatment on Silica Aerogels Prepared via Ambient Drying
%A Fei SHI
%A Lijiu WANG
%A Jingxiao LIU
%A Miao ZENG
%A <br>Fei
%A SHI
%A Lijiu
%A WANG
%A Jingxiao
%A LIU
%A Miao
%A ZENG
%J 材料科学技术学报
%D 2007
%I 
%X Silica aerogels were prepared at ambient drying by using ethanol/trimethylchlorosilane (TMCS)/heptane solution as pore water exchange and surface modification of the wet gel before drying. The obtained silica aerogels exhibit a sponge-like structure with uniform pore size distribution. The effects of heat-treatment on the hydrophobicity, specific surface area and other properties were investigated. The results indicated that the hydrophobicity of silica aerogels could be maintained up to 350℃. With increasing heating temperature, hydrophobicity decreased, and became completely hydrophilic after heat-treatment at 500℃. Brunaueremmitt-teller (BET) surface area results indicated that the specific surface area of silica aerogels increased with increasing heating temperature in the range of 150-500 ℃. The effects of heat-treatment on the morphology and chemical bonding state of silica aerogels were investigated by scanning electron microscopy (SEM),differential temperature analysis (DTA) and Fourier-transform infrared spectroscopy (FT-IR).
%K Silica aerogel
%K Ambient drying
%K Hydrophobicity
%K Specific surface area
%K Heat-treatment<br>硅石气凝胶
%K 热处理
%K 常压干燥
%K 疏水性
%U http://www.alljournals.cn/get_abstract_url.aspx?pcid=5B3AB970F71A803DEACDC0559115BFCF0A068CD97DD29835&cid=84529CA2B2E519AC&jid=324DC3CAB22330DB19158AE0A9B7BFA5&aid=BF0A4C689B27164B&yid=A732AF04DDA03BB3&vid=EA389574707BDED3&iid=38B194292C032A66&sid=EE23223CE4332BD7&eid=DA74B62FE4348759&journal_id=1005-0302&journal_name=材料科学技术学报&referenced_num=0&reference_num=22