PREPARATION OF EPOXY RESINS

摘要

An improved process for the preparation of epoxy resins comprising reacting at least one epihalohydrin with at least one aromatic material containing an active hydrogen atom reactive with an epihalohydrin in the presence of an organic solvent, an alkali metal hydroxide and optionally in the presence of a catalyst for the reaction between the aromatic active hydrogen-containing material and the epihalohydrin while controlling the concentration of water in the reaction mixture. The improvement comprises (1) drying the reaction mixture after completion of the reaction with the concentration of water is equal to or less than 2 percent by weight; (2) removing any insoluble materials from the reaction mixture by any suitable mechanical solid separation means thereby forming a resin/epihalohydrin/organic solvent mixture essentially free of insoluble material; (3) washing the resin/epihalohydrin/organic solvent material with water, so as to remove water soluble materials; (4) drying the resin/epihalohydrin/organic solvent mixture to a water content equal to or less than 2 percent by weight; and (5) recovering the resultant epoxy resin from the resin/epihalohydrin/organic solvent mixture by an suitable means. The present process maximizes epihlaohydrin yields and also produces epoxy resins low in hydrolyzable halide and total halide.