Patent ID: 8158710

Claim:
A composition having improved heat aging consisting of a blend of: 10 to 45 weight percent of a polyester selected from the group consisting of poly(ethylene terephthalate), poly(butylene terephthalate), poly(1,4-cyclohexyldimethylene cyclohexyl dicarboxylate), or a combination comprising at least one of the foregoing; and 55 to 90 weight percent of a poly(ester-ether) copolymer, each based on the total weight of the polyester and the poly(ester-ether) copolymer; wherein the poly(ester-ether) copolymer comprises units derived from terephthalic or a chemical equivalent thereof, units derived from butane diol or a chemical equivalent thereof, and 25 to 65 weight percent of units derived from poly(oxytetramethylene)glycol, based on the weight of the copolymer; optionally additives selected from the group consisting of antioxidants, flame retardants, light stabilizers, plasticizers, lubricants, antistatic agents, colorants, mold release agents, fillers, aromatic polycarbonates, polysulfones, polyethersulfones, and impact modifiers; wherein the elongation at break of the composition is larger than 150% after being exposed to a temperature of 140° C. for 4 weeks, as measured by ASTM D-638, and 0.1 to 5 weight percent of a carboxy reactive component consisting of an epoxide, based on the total weight of the composition, and optionally a catalyst that, if present, is selected from the group consisting of a hydroxide, hydride, amide, carbonate, phosphate, C 2-36 carboxylate, C 2-18 enolate, a C 2-36 dicarboxylate of an alkali metal, alkaline earth metal, or other metal; or a Lewis catalyst selected from the group consisting of a tin or titanium compound, a nitrogen-containing compound, a C 1-36 tetraalkyl phosphonium hydroxide or acetate; or an alkali or alkaline earth metal salt of a negatively charged polymer, and combinations thereof, exclusive of borate or other catalysts.