Process for separating low molecular weight compounds from polycaproamide melt with superheated steam

摘要

A process for separating low molecular weight compounds from a crude polycaproamide melt comprises heat treating the melt in vacuo with superheated steam, in an extruder having a plurality of degassing zones, under precise conditions of temperature, pressure and configuration, such that the occurrence of side reactions and dehydration of the melt are substantially eliminated, the molecular weight of the polymer during the heat treatment in vacuo, during transport and subsequent processing remains substantially unchanged, a residual content of low molecular weight compounds of