Polymerization of lactams, 92. Non-activated anionic polymerization ofε-caprolactam initiated with the sodium salt ofε-caprolactam

Abstract

The non-activated polymerization of e-caprolactam initiated with the sodium salt of e-caprolactam (CLNa), which was prepared in situ with sodium methoxide, was studied in the temperature range 170-230°C and at CLNa concentrations from 0.20 to 1.0 mol-%, and at 190°C in the presence of 2.0-10.0 mol-% CLNa. Apparent rate constants and values of apparent activation energy (E a ) were determined for the initial autoaccelerated stage of polymerization (E a = 230 kJ. mol -1 ) as well as for the stage characterized by a zero-order reaction with respect to the monomer (E a = 120 kJ. mol -1 ). Non-integral orders of the polyreaction with respect to the initiator indicate a highly complex polymerization mechanism. Degradation reactions accompany the polymerization at high polymer contents.