One- and two-dimensional NMR characterization of N-vinyl-2-pyrrolidone/methyl acrylate copolymers (vol 40, pg 2225, 2002)

N-vinyl-2-pyrrolidone/methyl acrylate (V/M) copolymers were prepared by free-radical bulk polymerization using benzoyl peroxide as an initiator. The copolymer composition of these copolymers was calculated from H-1 NMR spectra. The radical reactivity ratios for N-vinyl-2-pyrrolidone (V) and methyl acrylate (M) were r(V) = 0.09, r(M) = 0.44. These reactivity ratios for the copolymerization of V and M were determined using the Kelen-Tudos and nonlinear least-squares error-in-variable methods. The C-13{H-1} and H-1 NMR spectra of these copolymers overlapped and were complex. The complete spectral assignment of the C-13 and H-1 NMR spectra were done with distortionless enhancement by polarization transfer and two dimensional C-13-H-1 heteronuclear single quantum correlation spectroscopic experiments. The two-dimensional H-1-H-1 homonuclear total correlation spectroscopic NMR spectrum showed the various bond interactions, thus inferring the possible structure of the copolymers. (C) 2002 Wiley Periodicals, Inc.