A New Approach for Synthesizing the Hybrid Silica Aerogels

详细信息    查看全文

• 作者：Z. Talebi Mazraeh-shahi^a ; ^b ; ^{z.talebi@cc.iut.ac.ir" class="auth_mail" title="E-mail the corresponding author} ; A. Mousavi Shoushtari^b ; A.R. Bahramian^c
• 关键词：Hybrid aerogel ; Polyurethane/silica ; Ambient pressure ; Pore structure.
• 刊名：Procedia Materials Science
• 出版年：2015
• 出版时间：2015
• 年：2015
• 卷：11
• 期：Complete
• 页码：571-575
• 全文大小：246 K

文摘

Uniform Polyurethane/silica hybrid aerogels were achieved at ambient pressure via an approach in which an aqueous polyurethane dispersion was used and the hybridization step carried out before gelation step. The FT-IR spectra confirmed the incorporation of polymer chains into the silica network and hybrid network formation.

As the H₂O/TEOS molar ratio increased after hybridization in this method, the effect of H₂O/TEOS molar ratio changes and PU content on the density of hybrid aerogels was investigated separately. The density of native silica aerogels decreases commonly with increasing the water content while increasing the aqueous PU dispersion content increases the density of hybrid aerogels. The density difference between the hybrid aerogel sample with a certain aqueous PU dispersion and the similar native silica aerogel with the same H₂O/TEOS molar ratio demonstrated the intensive polyurethane chain effect on the aerogel density. The results showed that the simultaneous increase of H₂O/TEOS molar ratio and PU content could be led to the uniform structure of hybrid aerogels. However, the effect of polyurethane on the aerogel density was more sensitive than H₂O/TEOS molar ratio effect especially in high polyurethane content (≥10 wt.%) that increased the density of hybrid aerogels.