Production of polycaprolactam useful for making fibers or molding composition

摘要

In the production of polycaprolactam using an additive, an N,N'-bis(2,2,6,6-tetraalkylpiperid-4-yl)-iso or terephthalodiamide is added as chain regulator at any time between addition of the monomer and the start of polycondensation. In the production of polycaprolactam using an additive, an N,N'-bis(2,2,6,6-tetraalkylpiperid-4-yl)-iso or terephthalodiamide of formula R1-NH-OC-R2-CO-NH-R1 (I) is added as chain regulator at any time between addition of the monomer and the start of polycondensation; R1 = a group of formula (II); R2 = phenyl with substituents in the 1,3- or 1,4-position; R3 = hydrogen (H), 1-6C alkyl, 1-4C alkoxy or -CO-(1-4C)-alkyl; R4 = 1-5C alkyl.