One‐ and two‐dimensional NMR characterization of N‐vinyl‐2‐pyrrolidone/methyl acrylate copolymers

Abstract

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 1 H NMR spectra. The radical reactivity ratios for N-vinyl-2-pyrrolidone (V) and methyl acrylate (M) were r V ϭ 0.09, r M ϭ 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 13 C{ 1 H} and 1 H NMR spectra of these copolymers overlapped and were complex. The complete spectral assignment of the 13 C and 1 H NMR spectra were done with distortionless enhancement by polarization transfer and two dimensional 13 C-1 H heteronuclear single quantum correlation spectroscopic experiments. The two-dimensional 1 H-1 H homonuclear total correlation spectroscopic NMR spectrum showed the various bond interactions, thus inferring the possible structure of the copolymers.

Lithography application of a novel photoresist for patterning of cells

“…Copolymerization reactions provide an excellent way of preparing macromolecules with controlled properties such as hydrophilic/hydrophobic balances, polarity and film formation [12,13]. GPC showed that the molecular weight of MMA:TBNVP was 24,000 and the polydispersity was 1.80.…”