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Conformational transformations in chiral polythiophene derivatives aggregated in polymethacrylate matrices: Experiments and molecular dynamics simulationsстатья
Информация о цитировании статьи получена из
Web of Science,
Scopus
Статья опубликована в журнале из списка Web of Science и/или Scopus
Дата последнего поиска статьи во внешних источниках: 18 июля 2013 г.
- Авторы: Bjornholm T.a., Brostow W.b., Schaumburg K.a., Shibaev P.V.a.c, Sinani V.d., Vinokur R.c.
- Журнал: Macromolecular Symposia
- Том: 148
- Год издания: 1999
- Издательство: John Wiley & Sons Ltd.
- Местоположение издательства: United Kingdom
- Первая страница: 31
- Последняя страница: 45
- Аннотация: Chiral derivatives of poly(3-(S-3′,7′-dimethyloctyl)thiophene) embedded in either poly(methyl methacrylate) (PMMA) or poly(butyl methacrylate) (PBMA) were studied by polarization optical microscopy, UV absorption and circular dichroism (CD) spectroscopy as well as simulated using the Molecular Dynamics procedure. CD spectra change on heating to mirror spectra; for PMMA-containing blends the changes in heating/cooling cycles are reversible. The signs of CD spectra depend on free volume, the packing of side groups in particular. Since in the melt there are no restrictions on the positions of the chiral groups, those groups appears with equal probabilities at any locations with respect to the thiophene ring. By contrast, in clusters restrictions imposed by other alkyl chains result in positioning of chiral methyl groups preferentially on the left or right sides of the thiophene rings. The consequence is the formation of right or left twists in molecular backbones.
- Добавил в систему: Шибаев Петр Валерьевич