The Synthesis of Phenol–Formaldehyde Copolymers Based on Phthalide-Containing Monophenol

Abstract

When o-benzoylbenzoic acid chloride interacts with phenol in dioxane solution in the presence of catalyst ZnCl2, the phthalide-containing monophenol 3-phenyl-3-(4′-hydroxyphenyl)phthalide (I) is formed. When a mixture of the synthesised monophenol and phenol in different weight ratios (from 5:95 to 40:60) interacts with formaldehyde in the presence of catalytic amounts of ammonia, resol-type phenol–formaldehyde cooligomers are obtained, and heat-resistant crosslinked polymers based on them.