Effect of hydrolysis and drying on the siloxane bonds of a silane coupling agent deposited on E‐glass fibers

Molecular structural changes of a vinyl functional silane coupling agent on E-glass fibers, induced during the immersion test in hot water, have been studied using Fourier transform infrared spectroscopy. The amount of the coupling agent on the glass fibers is reduced by hydrolytic degradation. Silanol groups formed by the hydrolysis of the siloxane groups have been detected in the FT-IR difference spectrum in the range 930–840 cm−1 due to the SiO stretching mode of the SiOH groups. Heat treatment produces partial reformation of the siloxane bonds.