Preparation of silica microcapsules containing octadecane as temperature-adjusting powder

Abstract

Spherical microcapsules of silica-shelled octadecane are prepared in the presence of polyvinyl alcohol in an O/W emulsion. The silica shell forms via hydrolysis and condensation from tetraethyl silicate with acetatic acid as catalyst. The thermogravimetric curves show that the microcapsules have thermal stability superior to that of octadecane. The latent heat and the melting point of microcapsule are 162 J·g-1 and 30°C, respectively. Copyright © 2007 The Chemical Society of Japan.