| dc.contributor.author | Langner, Andreas | en_US |
| dc.contributor.author | Ehrlich, Paul | en_US |
| dc.date.accessioned | 2006-07-19T19:48:29Z | en_US |
| dc.date.available | 2006-07-19T19:48:29Z | en_US |
| dc.date.issued | 1990-04-19 | en_US |
| dc.identifier.citation | Macromolecules 23N8 (1990) 2203-2210 | en_US |
| dc.identifier.issn | 1520-5835 | en_US |
| dc.identifier.uri | http://hdl.handle.net/1850/2194 | en_US |
| dc.description.abstract | The line-shape and saturation analysis for inhomogeneously broadened ESR spectra, developed in the previous paper, is used to study the change of the PPA/Fe-Al resonance signal with temperature and polymer aging. A mechanism for radical formation, involving backbone cyclization reactions, is proposed to interpret the irreversible increase in spin concentration observed above -70 degrees C. As before, the spectra of the soluble and insoluble fractions of the polymer are interpreted as arising largely from triphenylcyclohexadienyl radicals formed upon cyclization of a cis-cisoid hexatriene precursor. An analysis of the resonance signal of the catalyst revealed that a low A1:Fe ratio at the active polymerization site leads to a high concentration of the cis-cisoid conformation. The presence of oxygen-complexed radicals with shorter spin-lattice relaxation times is inferred from saturation experiments. | en_US |
| dc.format.extent | 31371 bytes | en_US |
| dc.format.mimetype | application/pdf | en_US |
| dc.language.iso | en_US | en_US |
| dc.publisher | The American Chemical Society: Macromolecules | en_US |
| dc.subject | ESR spectra | en_US |
| dc.subject | Radicals | en_US |
| dc.subject | Saturation analysis | en_US |
| dc.title | Electron spin resonance study of radical formation in cis-poly(phenylacetylene)/ferric acetylacetonate-triethylaluminum (PPA/Fe-Al). 2. Results and interpretation | en_US |
| dc.type | Abstract | en_US |
| dc.identifier.url | http://dx.doi.org/10.1021/ma00210a013 | |
