Thermal stability and degradation mechanisms of trialkylsilyl surface modifications on silica powder

Abstract

Abstract The thermal stability of a number of trialkylsilyl surface modifications has been studied. During heating, weight loss is recorded by thermogravimetry, while evolved gases are simultaneously analysed with mass spectrometry. Changes in the molecular structure on the surface are measured with solid state nuclear magnetic resonance (NMR) and static‐SIMS. Degradation mechanisms are proposed and described by a number of reaction equations. The changes in surface chemistry on the internal powder surface as measured with NMR are similar to those observed with static‐SIMS on the outer surface of the powder particles.