Patent ID: 7638596

Claim:
A method of crystallizing polymeric pellets in a crystallizer having an inlet and an outlet, the method comprising: a) introducing a plurality of polymeric pellets, wherein the plurality of polymeric pellets have an initial average temperature between 135° C. and 200° C., into the inlet of the crystallizer, the plurality of polymeric pellets comprising a crystallizable polymer having a crystallization temperature and a melting temperature and the plurality of polymeric pellets having an average pellet temperature; b) adjusting a temperature of one or more regions of the crystallizer with a heat transfer jacket to provide the temperature of the one or more regions that is sufficient to allow at least partial crystallization of the plurality of polymeric pellets while maintaining the average pellet temperature below the melting temperature while the plurality of polymeric pellets is within the crystallizer, wherein at least a portion of the plurality of polymeric pellets crystallize from inside to outside; and c) removing the plurality of polymeric pellets from the outlet of the crystallizer, wherein the plurality of polymeric pellets are formed from solidifying a molten polyester polymer having an lt.V. of at least 0.70 dL/g.