Compositions comprising polyphenylene ether-polyester copolymers from epoxytriazine-capped polyphenylene ethers

Copolymer-containing compositions are prepared by the reaction of an epoxytriazine-capped polyphenylene ether with another polymer containing carboxy end groups, especially a polyester. The compositions have excellent properties and find utility as molding compositions and as compatibilizers for blends of similar polymers. Suitable epoxytriazine-capped polyphenylene ethers may be prepared by reaction of a polyphenylene ether with an epoxychlorotriazine such as diglycidyl chlorocyanurate, n-butyl glycidyl chlorocyanurate or mesityl glycidyl chlorocyanurate.