ON-LINE CONTROL OF MOLECULAR WEIGHT IN CONTINUOUS SOLID STATE POLYMERIZATION PROCESSES.

摘要

The invention relates to the on-line control of the molecular weight in continuous solid state polymerization processes. In particular it is directed to a polyester process or to a polyamide process, and more specifically to a poly (ethylene terephthalate) (PET) or a poly (butylene terephthalate) (PBT) or a nylon 6,6 continuous solid-state polymerization (SSP) process. An in-line viscometer melts and measures the molecular weight of the SSP resin and adjusts one or more of the process variables, i.e. reactor time, inert gas purity and inert gas temperature to maintain a constant resin molecular weight.