| 摘要 |
PROBLEM TO BE SOLVED: To produce an epoxy resin having a low total chlorine content by reacting a polyhydric phenol with an epihalohydrin in the presence of an alkali metal hydroxide while causing water in the system to flow out together with the epihalohydrin without allowing the outflow to return to the system. SOLUTION: A condensate of a phenol with an aldehyde or ketone is used as the polyhydric phenol. The phenol is phenol, o-cresol, or the like; the aldehyde is formaldhyde, acrolein, or the like; and the condensate is a novolak, a bisphenol, or the like. Epichlorohydrin is an example of the epihalohydrin. In terms of handleability, an aprotic polar solvent (e.g. dimethyl sulfoxide) may be used in the reaction. Sodium hydroxide in the solid form or as a 5-50 wt.% aqueous solution is used as the alkali metal hydroxide, and its amount is 10-300 pts.wt. based on 100 pts.wt. epihalohydrin.
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