Poly(vinylpyrrolidone): Configurational assignments by one- and two-dimensional NMR spectroscopy

✍ Scribed by Kaushik Dutta; A. S. Brar

• Publisher: John Wiley and Sons
• Year: 1999
• Tongue: English
• Weight: 170 KB
• Volume: 37
• Category: Article
• ISSN: 0887-624X
• DOI: 10.1002/(sici)1099-0518(19991101)37:21<3922::aid-pola7>3.0.co;2-j

✦ Synopsis

The configurational assignment of poly(vinylpyrrolidone) (PVP) prepared by peroxide-initiated solution polymerization was studied by the combination of oneand two-dimensional NMR spectroscopy. The broad and overlapping 1 H-NMR and 13 C{ 1 H}-NMR spectra of PVP were assigned to the configurational triad, pentad (CH, 2 CH 2 , 3 CH 2 , and 4 CH 2 regions), and tetrad (␤-CH 2 region) sequences. The configurational assignments of the various carbon resonances were confirmed with the help of two-dimensional experiments such as heteronuclear single quantum correlation (HSQC), heteronuclear single quantum correlation-total correlation spectroscopy (2-D HSQC-TOCSY). The various geminal and vicinal couplings within the configurational sequences were assigned with the help of total correlation spectroscopy (TOCSY low mixing time). The propagation pathway was studied using the 13 C{ 1 H}-NMR (carbonyl carbon) and 15 N{ 1 H}-NMR spectra. The 15 N{ 1 H} resonance signals were assigned to pentad-level configurational sequences. The results obtained by the analysis of the area under the resonance signals confirmed that poly(vinylpyrrolidone) obeys Bernoullian statistics.