Reaction of Phenyl Glycidyl Ether with Xylenols

Abstract

We discussed the behavior of epoxy groups in the curing reaction of ammoniacal resolewith epoxy resin using phenyl glycidyl ether (PGE), 2, 4-xylenol (2, 4-X) and its hydroxymethyl derivative (2, 4-XM) as models of above resin. And PhCHilTCH, PhOaH, (DBAO) which acts as catalyst was added tolhis, mixture as a model of intermediate reaction product of ammoniacal resol. The reaction conalitions were studied in the range from room temperature to 210° C. We confirmed by using NMR that, epoxy groups react mainly with phenoljc hydroxyl groups and form secondary hydroxyl groups, while hydroxymethyl groups in the resol produce methylene or dimethylene ether linkage by intramolecular condensation reaction. -We could-not, findany evidences for the reaction between epoxy and hydroxymethyl groups, although hydroxymethyl groups seemed to accelerate the reaction of epoxy groups with phenolic hydroxyl groups. Then we considered that proton released from phenolic hydroxyl groups as a result of intermolecular hydrogen bonding between hydroxymethyl groups and phenolic hydroxyl groups accelerated the above reaction.
DBAO promotes also the reaction of PGE with 2, 4-X or 2, 4-XM.
While with rising temperature, the ratio of reacted eP-ox-y groups to phenolic hydroxyl groups increases remarkably. This fact suggests that the epoxy groups react with secondary groups which are formed by the reaction between epoxy groups and phenolic hydroxyl groups.