Reaction of Silica with Tetraethyl Orthosilicate

摘要

The reaction of tetraethyl orthosilicate with fumed silica at various temperatures was investigated. It was found that essentially no reaction occurred at 25C or 100C after short reaction periods. At 165C, the reaction proceeds with both hydrated and predried silica glass surfaces. It was shown that silanol sites on the glass do take part in a reaction which results in the formation of new siloxane bonds. These sites can be rehydrated after thermal degradation of the treated surfaces in vacuum. (Author)