Trimethylethoxysilane (TMES) has been recognized as a good co-precursor to increase the degree of hydrophobicity during the synthesis of a silica aerogel because of its methyl groups. Therefore, some physical properties of silica aerogels, including the contact angle and porosity, were investigated using TMES as a co-precursor at different molar ratios with the main precursor such as tetramethoxysilane (TMOS) or tetraethoxysilane (TEOS). In contrast to TMES, most silylating agents such as hexamethyldisilazane (HMDZ) and trimethylchlorosilane (TMCS) have been used for surface modification because of their ability to enhance the hydrophobicity of the aerogel surface. This work examines the silylation effect, which includes increasing hydrophobicity by TMES to determine the possibility of using it as an alternative silylating agent during ambient pressure drying in the synthesis of sodium silicate-based silica aerogel. In addition, the physical properties of sodium silicate-based silica aerogels with silylation under different TMES/TMCS volume ratio are investigated. The physical properties of sodium silicate-based aerogels can be changed by the TMES/TMCS volume ratio during the surface modification step. Aerogels with a high specific surface area (458 m2/g), pore volume (3.215 cm3/g), porosity (92.7%), and contact angle (131.8°) can be obtained TMES/TMCS volume ratio of 40/60. [Figure not available: see fulltext.].
Bibliographical noteFunding Information:
This work was supported by Nano-Convergence Foundation (www.nanotech2020.org) funded by the Ministry of Science and ICT (MSIT, Korea) & the Ministry of Trade, Industry and Energy (MOTIE, Korea) [Project Name: Commercialization development of super thermal insulation aerogel composite foam for cold insulation material]. This work was supported by the Center for Advanced Meta-Materials (CAMM) funded by the Ministry of Science, ICT and Future Planning as Global Frontier Project (CAMM-No. NRF-2014M3A6B3063716). The authors declare that they have no conflict of interest.
All Science Journal Classification (ASJC) codes
- Electronic, Optical and Magnetic Materials
- Ceramics and Composites
- Condensed Matter Physics
- Materials Chemistry