Modeling the gelation of silicon alkoxides

摘要: Abstract This paper reviews the experimental evidence which suggests that gelation of alkoxides can be modeled using analyses developed for organic condensation polymerizations, and presents a model used to predict acid catalyzed silicon alkoxides. Parameters characterize polymerization products, such as weight averaged molecular weight, are calculated from extent reactions recursive solution technique applied random branching theory polymerization. The hydrolysis functions time kinetic schemes Assink Kay [J. Non-Cryst. Solids 99 (1988) 359; 104 112] Pouxveil Boilot 94 (1987) 347]. Results this modeling give versus conversion time. predictions gel times combined with models TMOS in reasonable agreement data Kelts Armstrong Mater. Res. 4 (1989) 423] if effects cyclization considered. For TEOS, scheme Boilot, is not good due larger cyclization.