1070-4272/05/7802-0295 C 2005 Pleiades Publishing, Inc.
Russian Journal of Applied Chemistry, Vol. 78, No. 2, 2005, pp. 295!300. Translated from Zhurnal Prikladnoi Khimii, Vol. 78, No. 2, 2005,
Original Russian Text Copyright + 2005 by Kurenkov, Zhelonkina, Kovalenko.
AND POLYMERIC MATERIALS
Concentration Effect in Copolymerization of Sodium
with N-Vinylpyrrolidone in Aqueous Solutions
V. F. Kurenkov, T. A. Zhelonkina, and V. I. Kovalenko
Kazan State Technological University, Kazan, Tatarstan, Russia
Received September 21, 2004
Abstract-The kinetics of copolymerization of sodium 2-acrylamido-2-methylpropanesulfonate with N-vinyl-
pyrrolidone in aqueous solutions in the presence of potassium persulfate at 40 370oC and the molecular char-
acteristics of the resulting complexes were studied, as influenced by the total concentration of the initial
monomer mixture, comonomer ratio, temperature, and conversion. The kinetic data were explained taking
into account the state of the ionic groups, electrostatic interactions between the reacting particles, and com-
plexation of comonomers in the course of copolymerization.
Radical copolymerization in aqueous solutions is
one of the main, but still insufficiently studied pro-
cedures for preparing water-soluble copolymers of
sodium 2-acrylamido-2-methylpropanesulfonate (Na-
AMS) with N-vinylpyrrolidone (VP), which exhibit
high flocculation , adhesive and antistatic proper-
ties , and thickening and complexing power and
show promise for various branches of industry and
medicine. In this study, copolymerization of Na-AMS
and VP was examined as influenced by concentration.
Being unusual from the standpoint of the classical
theory, this effect is due to specific features of co-
polymerization of ionic monomers  with, in partic-
ular, salts of unsaturated sulfonic acids [4, 5] and can
be described as a dependence of the polymer composi-
tion on the total concentration of the comonomers
in the course of copolymerization at fixed composi-
tion of the initial monomer mixture and conversion.
The concentration effect in copolymerization of Na-
AMS and VP has not been studied previously.
The properties of the starting compounds and the ex-
perimental procedures used (copolymerization, dilato-
metric analysis of the reaction kinetics, etc.) were simi-
lar to those described in . The initial rates of copoly-
, at low conversion (<4%) were deter-
mined from the kinetic curves obtained dilatometrically.
After copolymerization, the resulting polymers
were precipitated from aqueous solutions with ace-
tone, filtered off, washed with acetone, and dried
to constant weight in a vacuum at 50oC. The yield
of the copolymers was determined gravimetrically.
The content of ionic units in the copolymer of Na-
AMS and VP
was determined from the content of sulfur .
The molecular weight of copolymers (M) was cal-
culated with the Mark3Houwink equation from the in-
trinsic viscosity [h] of their solutions, which was
measured in a 0.5 M NaCl solution at 30oCon
a VPZh-3 viscometer (d
= 0.43 mm). The exper-
imental dependence of the reduced viscosity h
the copolymer concentration c
was plotted. Then, us-
ing the linear dependence h
), we de-
[h] = lim(h
The IR spectra were recorded on an Avatar 360
Fourier spectrometer (ThermoNicolet, the United
States) in the 40003400 cm
range using VP and
a solution of Na-AMS in VP (1 : 9 molar ratio)
prepared by mixing of alcoholic monomer solutions