Structure of Sol-Gel-Derived Inorganic Polymers: 2, Silicates and Borates

摘要

Many of the structural features of sol-gel-derived inorganic polymers are rationalized on the basis of the stability of the M-O-M condensation products in their synthesis environments. Structures which emerge in solution reflect a successive series of hydrolysis, condensation and, depending on the acid or base concentration, restructuring reactions. M-O-M bonds which are unstable with respect to hydrolysis or alcoholysis are generally absent. During consolidation, the condensation process continues within a very stiff matrix in a relatively inert environment. Under these conditions, metastable species may form which are temporarily stabilized by the high matrix viscosity and the absence of water and alcohol. 54 refs., 8 figs. (ERA citation 12:041398)