Preparation, characterization and thermal properties of titanium- and silicon-modified novolac resins

Titanium- and silicon-modified novolac (TSN) resins were prepared by the reaction of novolac resin with the organotitanium polysiloxane. TSN resins with a series of inorganic element contents were prepared, and the corresponding silicon fiber reinforced TSN composites (TSN/silica fiber) were fabricated by the compression molding procedure. The results of thermogravimetric analysis show that the thermal stability of TSN resins were improved by the introduction of inorganic element, both for the initial decomposition temperature and char yields. As the inorganic element increase, the thermal stability also increases initially and then subsequently decreases. Meanwhile, the storage modulus and glass transition temperature (T-g) of TSN resin composites were improved. TSN-3.12 composite shows the best thermal stability with T-g at 290 degrees C, which was 37 degrees C higher than that of the neat resin composite.