The Effect of Acid Concentration on the Synthesis of Hydrophobic Silica Based Aerogels

Abstract

Aerogel has a meaning of an air gel that made of a gel solution [1]. Aerogels are transparent and highly porous materials which known with low density. Since the 1930’s, researchers have been focused on the synthesis methods and applications of aerogels [2]. In recent years, silica aerogels have been widely used in optics, microelectronic, electrical engineering, acoustics, heat insulation, capture of micro particles, pharmaceutical, chemistry, and biology [1-3].

In this study, the effect of the acid concentration on the synthesis of hydrophobic silica based aerogel was investigated. Tetraethyl orthosilicate (TEOS) and chlorotrimethylsilane (TMCS) were used in the synthesis as a silica source and silylation reagent, respectively. Different concentrations (0.5 M, 1 M, and 1.5 M) of acid solutions were prepared in order to see the effect of acid concentration in the synthesis of silica based hydrophobic aerogel. The synthesized samples were characterized by Fourier transform infrared spectroscopy (FTIR) and contact angle analysis. The obtained results show that the optimum acid concentration was found as 0.5 M.

Keywords

• component; Silica based aerogel, acid concentration, FT-IR, contact angle.

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