Polyester polymer particles having a small surface to center molecular weight gradient

Abstract

Polyester polymer particle spheroids comprising a polyester polymer including: a carboxylic acid component containing at least 90 mole % of the residues of terephthalic acid, derivates of terephthalic acid, naphthalene-2,6-dicarboxylic acid, and/or derivatives of naphthalene-2,6-dicarboxylic acid, and a hydroxyl component containing from 90 to 96 mole % of the residues of ethylene glycol, based on 100 mole percent of the carboxylic acid component residues and 100 mole percent hydroxyl component residues in the polyester polymer, wherein said particle has an It.V. of at least 0.72 dL/g, and the It.V. at the surface of the particle is from 0.02 dL/g to less than 0.25 dL/g higher than the It.V. at the center of the particle, and wherein the polyester polymer spheroids are not solid state polymerized.

Dependencies are inferred from the claim text.