| abstract |
Process for the preparation of epoxy resins by reacting phenolic compounds and epihalohydrin. The goal is to reduce the consumption of epichlorohydrin while producing a high quality epoxy using a simple technology. This goal is achieved by adding to the reaction mixture consisting of phenolic compound and epihalohydrin, a dipolar aprotic solvent and at the reaction temperature of 288 to 353 K Alkalihydroxidloesung added so that the pH of the homogeneous liquid reaction mixture is maintained at 7 to 9 , After separation of the Epihalogenueberschusses and the solvent by distillation, the separation of the alkali halide is carried out by filtration. Suitable dipolar aprotic solvents are dimethyl sulfoxide, diethylene glycol dimethyl ether, tetramethylene sulfone, dimethylformamide, dimethylacetamide, N-methylpyrrolidone and N-methylcaprolactam. |