Preparation of sol–gel hybrid materials from γ-methacryloxypropyltrimethoxysilane and tetramethyl orthosilicate: study of the hydrolysis and condensation reactions

摘要

Organic–inorganic hybrid materials suitable for\udthe development of sol–gel coatings for metallic surfaces\udwere prepared by hydrolysis and condensation of γ-\udmethacryloxypropyltrimethoxysilane (MAPTMS) and tetramethyl\udorthosilicate (TMOS). The hydrolysis of MAPTMS/\udTMOS was carried out in an ethanol/water solution. The\udprehydrolysis stage of MAPTMS/TMOS system was\udmonitored by Fourier transform infrared spectroscopy\ud(FTIR) and liquid-state 29Si and 13C nuclear magnetic\udresonance (29Si and 13C NMR). FTIR analysis indicated\udthat the hydrolysis of MAPTMS/TMOS was accomplished\udas far as the (SiOMe) band corresponding to unhydrolyzed\udsilane disappeared. The concentration of the alkoxy groups\udand the extent of self-condensation of mono-, di-, and\udtrisubstituted siloxanes (T species) in the sol were estimated\udby using liquid-state 29Si NMR spectroscopy. The hydrolysis\udof the prepared sol was also evaluated by liquid-state\ud13C NMR spectroscopy. The results indicated that under the adopted synthesis strategy conditions, the hydrolysis\udprocess requires 4 h to be completed.