| abstract |
The present invention relates to a polyester resin for extrusion blow molded containers comprising a branched copolymer and fumed silica to improve the aged drop performance said branched copolyester is made from the reaction of purified terephthalic acid or its dimethyl ester, ethylene glycol, bifunctional diacid other than terephthalic acid, diol other than ethylene glycol, and multifunctional compound having a least 3 carboxyl groups, hydroxyl groups and/or ester forming groups thereof, said fumed silica has a particle size of 0.1 to 5 microns and is present at about 100 ppm to about 2,500 ppm based on the weight of said copolyester. |