Article ID | Journal | Published Year | Pages | File Type |
---|---|---|---|---|
1197728 | Journal of Analytical and Applied Pyrolysis | 2007 | 7 Pages |
Abstract
The reactive end groups of nonvolatile oligomers obtained by controlled thermal degradation of poly(propylene-ran-ethylene) and poly(propylene-ran-1-butene) were determined by 1H and 13C NMR spectroscopy. The molar ratio of unsaturated to saturated end groups was found to be about 9:1. The average number of unsaturated end groups per molecule was between 1.6 and 1.8, indicating that 60-80Â mol% of the oligomer molecules were telechelic, having two terminal unsaturated end groups. These oligomers had a lower polydispersity than the raw material, despite their lower molecular weight and melting temperature. Although the end groups resulting from each monomer unit could be detected by 13C NMR, the end group composition differed from that of the main chains of the raw materials. The end group composition was satisfactorily explained by the differences in bond dissociation energy and activation energy of elementary reactions that occurred during thermal degradation, based on the monomer composition of the raw materials.
Related Topics
Physical Sciences and Engineering
Chemistry
Analytical Chemistry
Authors
Daisuke Sasaki, Yoshihiro Suzuki, Hagiwara Toshiki, Shoichiro Yano, Takashi Sawaguchi,