Patent ID: 8039578
Filing Date: 2011-10-18
Classification: B29B,C08G,C08J,F26B,Y10T

Abstract:
1. A polyester polymer production process comprising: (a) forming polyester polymer particles from a polyester polymer melt in a particle forming zone, said polyester polymer melt comprises a carboxylic acid component and a hydroxyl component; (b) subsequent to step (a), quenching at least a portion of said particles via contact with a quench liquid in a quenching zone; (c) subsequent to step (b), drying at least a portion of said particles in a drying zone; (d) subsequent to step (c), crystallizing at least a portion of said particles in a crystallizing zone; and (e) subsequent to step (d), annealing at least a portion of said particles in an annealing zone wherein said particles have a residence time in said annealing zone of between 1 hour and 24 hours, wherein at all points during and between steps (b) through (e) the average bulk temperature of said particles is maintained above 165° C., wherein the It.V. of said particles produced from said particle forming zone is within about 5 percent of the It.V. of said particles produced from said annealing zone, and wherein said carboxylic acid component comprises at least 80 mole percent of the residues of terephthalic acid and/or derivatives thereof, wherein said hydroxyl component comprises at least 80 mole percent of residues of ethylene glycol and a modifier hydroxyl component comprising 1,4-cyclohexanedimethanol residues, wherein the total mole percentage of the glycol portion of the polyester is 100 mole percent.