PREPARATION OF CAST POLYAMIDES USING SPECIAL ACTIVATORS

摘要

A system containing lactam and a catalyst suitable for anion polymerization of lactam is provided to prepare cast polyamide with excellent crystallinity which does not initiate anion polymerization as soon as contact with lactam or after contact. A system comprises (a) at least one kind of catalyst for anion polymerization of lactam, and (b) at least one kind of activators for anion polymerization of lactam. At least one kind of the activators is selected from group consisting of cyclic isocyanate, allophanate and their mixture. The cyclic isocyanate is a dimmer, trimer, oligomer or polymer.