English Abstract

Characterization of Chloroprene Rubber by High Resolution 13C-NMR Spectroscopy

Takayuki SAITO
Kazumi NAKAYAMA
Tomoko WATANABE
Yoshito OHTAKE
Chemicals Evaluation and Research Institute, Japan, Sugito-Machi, Kitakatusika-Gun, Saitama, Japan
Nippon Gomu Kyokaishi,(2011),84(2),43-48 Original Paper in Japanese

Signals in 13C-NMR spectrum for polychloroprene were re-assigned through 1D and 2D NMR spectroscopy, that is, distortionless enhancement by polarization transfer (DEPT), heteronuclear multiple quantum correlation (HMQC), and heteronuclear multiple bond correlation (HMBC) measurements. The unknown signals at 40.1, 43.0, 45.5, 128.4, 129.1, and 130.1 ppm in 13C-NMR spectrum for raw chloroprene rubber were assigned to secondary carbon of 1,2 unit, secondary carbon of 1,4 unit adjacent to 3,4 unit, tertiary carbon of 3,4 unit, tertiary carbon of 1,4 unit adjacent to 3,4 unit, quaternary carbon of 1,4 unit adjacent to 1,2 unit, and tertiary carbon of 1,4 unit adjacent to 1,2 unit, respectively.
The resulting information on the assignments was used for characterization of chloroprene rubber vulcanizate and aged chloroprene rubber vulcanizate.

Keywords: Chloroprene Rubber, NMR, Degradation, Characterization, Assignment, Vulcanization