POLYESTER FIBERS MODIFIED WITH CARBODIIMIDES AND PROCESS FOR THEIR PREPARATION

摘要

Polyester fibers and filaments which contain carboxyl end groups closed off by reaction with carbodiimides, wherein the closing off of the carboxyl end groups has predominantly been carried out by reaction with mono- and/or biscarbodiimides which the fibers and filaments still contain in the free form, however in as little an amount as less than 30 ppm (by weight) of the polyester, the content of free carboxyl end groups is less than 3 meq/kg of polyester and the fibers and filaments still contain at least 0.05% by weight of at least one free polycarbodiimide or a reaction product which still contains reactive carbodiimide groups, and a process for their preparation are described. The filaments described are particularly suitable for the production of paper making machinery screens.