Interpenetrating networks obtained by crosslinking in the vinylacetate (VAc)-triethoxyvinylsilane (VTES)-tetraethoxysilane (TEOS) system

In the present work the sol-gel process in the ternary system VAc-VTES-TEOS was approached. The monomer that ensures the crosslinking of the obtained networks is VTES, which could react with VAc by free-radical polymerisation and with TEOS by hydrolysis-polycondensation. The early stage evolution of the process was monitored by gas chromatography coupled with mass spectrom etry (GC-MS). The gels obtained were characterised by IR spectroscopy, DTA/ TG analysis and DSC measurements. Important differences in the gelling proc ess and in the properties of the obtained gels could be noticed, related to the presence of VAc and VTES in the reaction mixtures. The investigation a llowed to establish the compositions and the experimental conditions in whi ch gels with high degree of crosslinking could be obtained.