Postcrosslinking of linear polyesters. II. UV‐induced crosslinking agents having carboxyl reactive group

Abstract

AbstractA previous article reported that polyallyl compounds such as triallyl cyanurate could be applied as an effective melt‐blend‐type ultraviolet (UV)‐induced crosslinking agent for linear polyesters to improve their thermal resistances without sacrificing their melt processabilities. The present article reports the results from further investigation to seek more effective crosslinking agents for the polyesters. Compounds having both allyl and carboxyl reactive groups, such as diallyl glycidyl isocyanurate and 2‐[β‐(3,5‐diallylisocyanuro)ethyl]carbamoyl‐2‐oxazoline have been proved to be more effective UV‐induced crosslinking agents than the simple polyallyl compounds reported previously. The former compounds were coupled with carboxyl terminal groups of the polyesters by reaction in the melt and act as an effective UV‐induced crosslinking agent, which was proved by the observation that the polyester having more carboxyl terminals resulted in higher UV crosslinkabilities. Addition of such compounds to the polyester did not seriously affect the melt stability of the mixtures.