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6635771 
Journal Article 
Characterization of 4-vinylpyridine-styrene copolymer by NMR spectroscopy 
Hooda, S; Brar, AS; , 
2001 
1 
Indian Journal of Chemistry. Section A
ISSN: 0376-4710
EISSN: 0975-0975 
NATL INST SCIENCE COMMUNICATION 
NEW DELHI 
40 
5 
483-490 
English 
WOS:000168832900010 
4-Vinylpyridine-styrene (V/S) copolymers of different compositions have been prepared by free radical bulk polymerization. The copolymer composition has been calculated from H-1 NMR spectra. The co-monomer reactivity ratios of V/S copolymer have been calculated from Kelen - Tudos (KT) and non-linear error in variables methods (EVM). The reactivity ratios obtained from KT and EVM are r(V) = 0.85, r(S) = 0.67 and r(V) =0.80 +/- 0.20, r(S) = 0.66 +/- 0.05 respectively. The copolymerization parameters such as conditional probabilities, number - average sequence lengths and block character in the copolymers have been calculated from C-13{H-1} NMR spectra. The observed triads concentration as determined from C-13{H-1} NMR spectra are in good agreement with those calculated from statistical model using terminal model reactivity ratios. The complete spectral assignment of these copolymers has been done with the help of Distortionless Enhancement by Polarization Transfer (DEPT) and two dimensional heteronuclear single quantum coherence (HSQC) spectra. The various type of H-1 - H-1 couplings in copolymer are assigned with the help of 2D-Total correlated spectroscopy (TOCSY).