Collect. Czech. Chem. Commun. 1985, 50, 840-844
https://doi.org/10.1135/cccc19850840

The equilibrium acidity of substituted N-(phenylcarbamoyl)-6-hexanelactams and disubstituted ureas and their effect on the anionic polymerization of lactams

Bohumír Valtera, M. I. Terekhovab, E. S. Petrovb, Jaroslav Stehlíčeka and Jan Šebendaa

a Institute of Macromolecular Chemistry, Czechoslovak Academy of Sciences, 162 06 Prague 6, Czechoslovakia
b Karpov Institute of Physical Chemistry, 107 120 Moscow B-120, U.S.S.R.

Abstract

The equilibrium acidity of substituted N-(phenylcarbamoyl)-6-hexanelactams, N-butyl-N'-phenylurea and N,N'-diethylurea was determined spectrophotometrically in dimethyl sulfoxide. Using the determined pK values, the effect of activator acidity of the N-(phenylcarbamoyl)-lactam type on the anionic polymerization of lactams was estimated, and the possible effect of the individual types of urea on the concentration of lactam anions was predicted.