SYSTEM FOR POLYMER CRYSTALLIZATION

摘要

A system for crystallization of polymers involving the use of a stationary housing with a rotor mounted for rotation within the housing. The rotor supports a plurality of spaced apart hollow discs and heated fluid is delivered to the interior of the discs. The polymer material to be treated is fed into the housing for heat exchange contact with the exterior surfaces of the discs. The rotation of the discs in addition serves as the propelling force for the material along the length of the housing at which point the material is discharged. The speed of rotation of the rotor is controlled to influence agitation and conveying of material in the housing to thereby control the crystallization reaction. A holdup mechanism which operates independently of the speed control is located adjacent the discharge location to contribute to the fixing of the residence time. The material inlet operation, discharge operation and residence control are such that the ratio of crystallized to uncrystallized material is maintained within desired limits, typically at about 4 to 1. The method and apparatus provides various other operating parameters and structural features which maximize the efficiency of the crystallization reaction.