Article ID | Journal | Published Year | Pages | File Type |
---|---|---|---|---|
5204913 | Polymer Degradation and Stability | 2006 | 5 Pages |
Abstract
The geometry of N,Nâ²-diphenyl-p-phenylenediamine (DPPD), N-phenyl-Nâ²-(1â²-methylbenzyl)-p-phenylenediamine (SPPD), N-phenyl-Nâ²-(1,3-dimethyl-butyl)-p-phenylenediamine (6PPD), N-phenyl-Nâ²-isopropyl-p-phenylenediamine (IPPD), and N-(1-methyl-1-phenylethyl)-Nâ²-phenyl-p-phenylenediamine (CPPD) as well as of their dehydrogenation products has been optimized at B3LYP/6-31Gâ level of theory. Our results support the idea of formation of stable ketimine Ph-NC structures (instead of quinonediimine structures) during consecutive dehydrogenation of SPPD, 6PPD, and IPPD antioxidants despite the formation of tertiary carbon-centered radicals in the first dehydrogenation step is energetically preferred for SPPD only.
Related Topics
Physical Sciences and Engineering
Chemistry
Organic Chemistry
Authors
M. Breza, I. KortiÅ¡ová, Z. Cibulková,