Process to control the curing reaction between a copolyester resin and an epoxide compound, and a composition formed for that process

摘要

A copolyester resin having modified termini is disclosed, as well as the method for making and using that compound in subsequent reactions with epoxide curing compounds. The polymerization of the copolyester resin may include a compounding preparation stage for modifying the termini of the copolyester resin by reacting those end groups with an aromatic acid to alter the activation energy necessary to cure the modified copolyester resin with the epoxide compound upon mixing and heating of that mixture in a powder coating upon a substrate. The modified copolyester resin improves impact strength and leveling properties between 300 DEG and 450 DEG F., which is desirable for protection of the underlying substrate.