Local Mechanism of Phenyl Ring π-Flips in Glassy Polycarbonate
| Autor: | Robert Yaris, Duane R. Whitney |
|---|---|
| Rok vydání: | 1997 |
| Předmět: |
Mathematics::Commutative Algebra
Polymers and Plastics Chemistry Organic Chemistry Order (ring theory) Activation energy Ring (chemistry) Molecular physics Rotational energy k-nearest neighbors algorithm Inorganic Chemistry Chain (algebraic topology) visual_art Polymer chemistry Materials Chemistry visual_art.visual_art_medium Polycarbonate Langevin dynamics |
| Zdroj: | Macromolecules. 30:1741-1751 |
| ISSN: | 1520-5835 0024-9297 |
| DOI: | 10.1021/ma9611432 |
| Popis: | In order to obtain the mechanism for the infrequent phenyl ring π-flips in glassy polycarbonate, a generalized Langevin dynamics simulation was performed on a reduced model consisting of a flipping ring and its keeper ring. The frequency of π-flips and activation energy for π-flips obtained from the simulation are in agreement with experiment. A phenyl ring π-flip occurs when there is an increase in the separation distance between the ring and its nearest neighbor ring on another chain, accompanied by, and in synchrony with, an increase in its rotational kinetic energy. |
| Databáze: | OpenAIRE |
| Externí odkaz: |
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