Complete spectral assignment of poly(N-vinylcarbazole-co-methyl acrylate)s by NMR spectroscopy

Abstract

The copolymers of N-vinylcarbazole/methyl acrylate (V/M) of different compositions were prepared by solution polymerisation using 2,2'-Azobisisobutyronitrile (AIBN) as an initiator and their composition was determined from quantitative 13C{1H} NMR spectroscopy. Reactivity ratios for the comonomers were calculated using the Kelen-Tudos (KT) and non-linear error in variable methods (EVM). The complete spectral assignment of the overlapping 1H and 13C{1H} spectra of the copolymers were done with the help of Distortionless Enhancement by Polarization Transfer (DEPT), two dimensional heteronuclear single quantum correlation (HSQC) and total correlated spectroscopy (TOCSY). The assignments of various compositional sequences were done in the carbon resonance signals of the methoxy region of M unit, the methine region of both V and M units and the methylene region of both V and M units.