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Abstract
The dependence of the hydrolysis and condensation kinetics of y-ureidopropyltrimethoxysilane on the pH in the water-methanol system at 23 °C was investigated by FTIR spectroscopy. Hydrolysis rate constants were calculated by nonlinear regression of the absorbance vs. time data for the CH3 rocking spectral band of the Si-O-CH3 group using SAS/STAT® software. It was found that γ-ureidopropyltrimethoxysilane was most stable in the water-methanol system at pH 7.7, since the rate of the first hydrolysis step was relatively slow at this pH. The rate of overall condensation of silanols produced by hydrolysis was qualitatively analyzed. These silanol groups are relatively more stable around pH 4.87, in comparison with those at the higher pH values.
