NMR spectroscopy of poly(vinyl chloride) defects. 2. ¹H and ¹³C NMR analysis of the terminal vinyl end group, 1,3-dichlorobutyl end group and chloromethyl branch

• Published in: Macromolecular symposia. Vol. 86; no. 1; pp. 65 - 75
• Main Authors: Benedikt, George M, Goodall, Brian L, Rhodes, Larry F, Kemball, Alan C
• Format: Journal Article
• Language: English
• Published: Hüthig & Wepf Verlag 01.09.1994
• ISSN: 1022-1360; 1521-3900
• DOI: 10.1002/masy.19940860107

We have been able to obtain the ¹H NMR subspectra of most of the major saturated end groups in PVC. In order to assign the terminal vinyl (TV) group, CH₂CH-CHCl-, we synthesized and analyzed the symmetrical model compound 3,5-dichloro-1,6-heptadiene (4) containing a racemic (r) and a meso (m) isomer. They exhibit distinct NMR signals for the vinyl protons, which allowed us to subsequently assign the r diad and the previously unreported m diad terminal vinyl resonances present in very small amounts in commercial PVC. The study of the solvent induced chemical shifts of the vinyl protons in an experimental PVC sample containing an unusually high level of this end group allowed us to further assign it in terms of the terminal rr, rm, mm and mr triads.