Modified phenol–formaldehyde novolac resins: Synthesis and thermal oxidative degradation

Abstract

Abstract New phenolic resins containing titanium and silicon in the main polymer structure were synthesized and some of their properties were investigated. Titanium and silicon contents of the polymers ranged from 2 to 13% titanium and from 2 to 5% silicon. These polymers became insoluble and infusible as the titanium and silicon contents of the products were increased. IR spectra of these modified resins were presented. The thermal oxidative degradations of the phenolic resins modified with titanium and silicon were also investigated using thermogravimetry and differential thermal analysis. Titanium and silicon‐modified polymers, showed considerably lower weight changes as compared with those of unmodified or titanium‐modified polymers, but the rate of the last oxidative degradation increased and the final degradation temperature decreased with increasing titanium concentration. The best results for the thermal resistance was found to be 2% ≤ Ti ≤ 6% and Si 2–5%.