Patent ID: 8039577

Claim:
A process for producing a polyester composition, comprising: an esterification step comprising transesterifying a dicarboxylic acid diester with a diol, or directly esterifying a dicarboxylic acid with a diol, to obtain one or more of a polyester monomer or a polyester oligomer; a polycondensation step comprising reacting the one or more of a polyester monomer or a polyester oligomer in a polycondensation reaction in the presence of a polycondensation catalyst to produce a polyester polymer having an It.V. from about 0.50 dL/g to about 1.1 dL/g; a particulation step in which the molten polyester polymer is solidified into particles; an optional solid-stating step in which the solid polymer is polymerized to an It.V. from about 0.70 dL/g to about 1.2 dL/g; and a particle addition step comprising adding and dispersing titanium nitride particles to provide an amount from about 1 ppm to about 50 ppm by weight of the polymer, wherein the particle addition step occurs after the esterification step and prior to the polycondensation step.