PROCESS FOR PREPARING LOW-MOLECULAR EPOXIDE RESINS

摘要

In the present invention there is disclosed a process for preparing low-molecular epoxy resins in a discontinuous process formed by condensation of epichlorhydrin with dian in molar ratio 2.1 to 10 : 1 by reacting thereof with an alkali metal hydroxide in two stages, wherein the intermediate of the first stage containing 0.5 to 1.9 percent by weight chlorine is formed by making use of 95 to 100 percent of sodium hydroxide based on dian, the residual epichlorhydrin is distilled off , whereupon the reaction product containing O.5 to 1.9 percent by weight chlorine is dissolved in aromatic hydrocarbons or aliphatic ketones to 30 to 70 percent solution, optionally sodium chloride formed by reaction in the first preparation stage is separated and subsequent dehydrochlorination proceeds for a period ranging from 15 to 240 minutes at a temperature ranging from 30 to 40 degC and in 10 to 900 percent excess of sodium hydroxide based on the chlorine content being present in the intermediate of the first stage and finally the product is isolated by usual processes.