Polymerization of lactams, 81. Anionic polymerization of lactams accelerated with N‐iminolactams, 2 ϵ‐caprolactam (6‐hexanelactam)

Abstract

The anionic polymerization of e-caprolactam (CL), initiated with the sodium or potassium salt of CL, was shown to be accelerated with l-(l-pyrrolin-2-yl)-2-pyrrolidone (I), 1 -(l-azacyclohept-1 -en-2-yl)-2-pyrrolidone (2), 1 -( 1 -azacyclonon-1 -en-2-yl)-2-pyrrolidone (3), 1 -( 1 -azacyclohept-1 -en-2-yl)-l -azacycloheptan-2-one (4) and 1 -(phenyliminornethyl)-2-pyrrolidone (S), both above and below the melting temperature of the polymer (150-230°C). The postpolymerization of the product was followed at 180 "C for certain cases. 0025-1 16)</88/$03.00*) The structure of 4 was erroneously described as a symmetrical ether (di-e-caprolactim ether) in earlier papers.

Synthesis and characterization of poly(ε‐caprolactones) and poly(δ‐valerolactone): Macroactivators for obtaining poly(esteramides)

“…The monomer ε-caprolactam (CLA; Merck, Darmstadt, Germany) was dried in a vacuum oven, over P 2 O 5 at 60˚C for 5 days. The initiator, sodium salt of caprolactam (NaCL), was synthesized and purified according to Brozek et al 16 Isophorone diisocyanate (5-isocyanate 1-isocyanatomethyl-1,3,3trimetylcyclohexane) (IF; Merck), and chloroform (CHCl 3 ; Merck) utilized for extraction of the obtained copolymers, were used as received. Toluene (C 7 H 8 ; Merck) was purified by distillation, which was followed by drying over sodium.…”

Study of multiblock polyamide-6/Poly-(isoprene) copolymers by positron annihilation spectroscopy

“…The initiator, sodium salt of caprolactam (Na-CL), was synthesized and purified according to [7]. Hexamethylene diisocyanate HM (1,6-diisocyanatohexane) (Merck) was used without further purification.…”

Polyamide‐6‐b‐polybutadiene block copolymers: Synthesis and properties

“…The initiator, sodium salt of caprolactam (NaCl), was synthesized and purified according to ref. 15. Benzene (Merck, USA) was dried and distilled over calcium hydride.…”