A. Gallardo et al., Micellar electrokinetic chromatography applied to copolymer systems with heterogeneous distribution, MACROMOLEC, 32(3), 1999, pp. 610-617
The kinetic analysis and the characterization of copolymer systems at high
conversion based on the free radical polymerization of N-vinylpyrrolidone,
VP, and 2-hydroxyethyl methacrylate, HEMA, is analyzed on the basis of the
reactivity ratios of these monomers as obtained by the Tidwell and Mortimer
nonlinear method. Characterization of copolymers prepared at different con
version degrees was carried out by using micellar electrokinetic chromatogr
aphy, MEKC, as well as by size exclusion chromatography, SEC. The experimen
tal results obtained demonstrate a noticeable change of the composition of
copolymer chains with the conversion degree and a good agreement between th
e approximation of the Skeist's kinetic treatment and the experimental data
. Both MEKC and SEC provide valuable complementary information with respect
to the average composition of copolymer chains and their macromolecular si
ze and size distribution. To our knowledge this is the first time that MEKC
has been applied to the characterization of high molecular weight copolyme
r systems.