Chemical Design of Elastomers
Abstract
Solid state C-13 nuclear magnetic spectroscopy has been extended to the study of the accelerated sulfur-vulcanization of natural rubber. Natural rubber vulcanizates which had been cured with elemental sulfur only, were studied by this particular technique. The NMR spectra that were obtained for these systems provided significant structural information on the natural rubber network. In this study, the samples are formulated with sulfur, accelerators and activators in order to study the effects of the various components in the crosslinking process of natural rubber. The NMR spectra indicate that a simpler network structure is obtained with accelerated sulfur vulcanization as compared to the systems cured with high levels of elemental sulfur. Solution C-13 NMR model compound studies have indicated that polysulfides terminated by accelerator residues will be indistinguishable from polysulfidic crosslinks. In the natural rubber vulcanizates, polysulfidic crosslinks have been observed in addition to the pendant accelerator groups. Cis-to-trans chain isomerization has been found to occur in these vulcanizates. Keywords: Tank pads, Rubbers, Track vehicles, Vehicular tracks.
Document Details
- Document Type
- Technical Report
- Publication Date
- May 19, 1987
- Accession Number
- ADA182905
Entities
People
- Jack L. Koening
Organizations
- Case Western Reserve University