Encapsulation of wax in complete silica microcapsules

Herein, we report a facile approach to fabricate silica capsules with encapsulated wax (WSC). These capsules have been formed based on O/W Pickering emulsion stabilized by hexadecyltrimethoxysilane-modified silica nanoparticles. These partially hydrophobic silica nanoparticles present at the interface are further bound together by silica layer formed by the sol-gel reaction of polymeric silica precursor. Molecular dynamics simulations have also been done to investigate the surface-modified silica nanoparticles at polar-nonpolar solvent interface. Further, the effect of various synthesis parameters on capsules formation has been systematically investigated. Capsules formed in this process completely consist of inorganic silica and the approach has also been extended for the encapsulation of different waxes as phase change materials. This simple and facile method allows the microencapsulation of wax in silica capsules with high encapsulation efficiency. The developed capsules can be a promising candidate as an active micro-filler in dental cements.

Automated summary

We present a simple method to fabricate silica capsules encapsulated with wax using hexadecyltrimethoxysilane-modified silica nanoparticles. These capsules are formed through O/W Pickering emulsion stabilized by the hydrophobic silica nanoparticles at the interface. Molecular dynamics simulations were conducted to analyze the surface-modified silica nanoparticles at the polar-nonpolar solvent interface. The encapsulation efficiency of different waxes as phase change materials was investigated, making these capsules a promising candidate for active micro-fillers in dental cements.