29 Si NMR, Sec and Ftir Studies of The Hydrolysis and Condensation of Si(OC 2 H 5 ) 4 and Si 2 O(OC 2 H 5 ) 6

The hydrolysis and initial condensation reactions of Si(OC 2 H 5 ) 4 and low order polyethoxysiloxanes have been studied with high resolution 29 Si NMR and size exclusion chromatography/FTIR spectroscopy. The effects of various parameters such as H 2 O/TEOS mole ratio, catalyst, pH, solvent, temperature and aging have been observed in the different nature of the reaction products. The products include partially hydrolyzed and unhydrolyzed Si(OC 2 H 5 ) 4 , Si 2 O(CH 2 H 5 ) 6 , and Si 3 O 2 (OC 2 H 5 ) 8 . The rate of formation and concentration of each product obtained under different conditions provides information about the reactivity of various silanol-containing species and the factors that affect the overall reaction scheme.