Patent ID: 7884177
Filing Date: 2011-02-08
Classification: C08G

Abstract:
1. A process for the continuous polycondensation of polyester material in a solid phase comprising the steps of passing a flow of hot gas through a fluidized bed of polyester granulate to heat the polyester granulate at a rate of from 50° C./minute to 100° C./minute to a temperature in a range of from 200° C. to 235° C.; passing the heated polyester granulate from the fluidized bed through a post-crystallizer in heat exchange relation with a flow of heated gas to maintain the temperature of the polyester granulate in a range of from 200° C. to 250° C.; and thereafter passing the polyester granulate from the post-crystallizer into a cooler in heat exchange relation with a flow of cooling gas to reduce the temperature to under 60° C. after solid state polymerisation.