PROCESS FOR PREPARING PHENOLIC RESIN BINDERS FOR FOUNDRY AND REFRACTORY USES

摘要

A process for preparing modified phenolic resole resins providing improved binders for refractories and foundry cores and molds. The resins are prepared by treating a phenol with a molar excess of aldehyde in the presence of an alkaline catalyst followed by further reaction at a pH below 7 in the presence of a catalyst which promotes formation of ortho-ortho benzylic ether bridges between the phenolic nuclei.