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Titanium Complexes of Dialkanolamine Ligands as Initiators for Living Ring-Opening Polymerization of epsilon-Caprolactoneстатья
Статья опубликована в высокорейтинговом журнале
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: Piskun Yulia A., Vasilenko Irina V., Kostjuk Sergei V., Zaitsev Kirill V., Zaitseva Galina S., Karlov Sergei S.
- Журнал: Journal of Polymer Science, Part A: Polymer Chemistry
- Том: 48
- Номер: 5
- Год издания: 2010
- Издательство: John Wiley & Sons Inc.
- Местоположение издательства: United States
- Первая страница: 1230
- Последняя страница: 1240
- DOI: 10.1002/pola.23886
- Аннотация: The titanium complexes with one (1a, 1b, 1c) and two (2a, 2b) dialkanolamine ligands were used as initiators in the ring-opening polymerization (ROP) of epsilon-caprolactone. Titanocanes 1a and 1b initiated living ROP of epsilon-caprolactone affording polymers whose number-average molecular weights (M(n)) increased in direct proportion to monomer conversion (M(n) <= 30,000 g mol(-1)) in agreement with calculated values, and were inversely proportional to initiator concentration, while the molecular weight distribution stayed narrow throughout the polymerization (M(w)/M(n) <= 1.2 up to 80% monomer conversion). (1)H-NMR and MALDI-TOF-MS studies of the obtained poly(epsilon-caprolactone)s revealed the presence of an isopropoxy group originated from the initiator at the polymer termini, indicating that the polymerization takes place exclusively at the Ti-O(i)Pr bond of the catalyst. The higher molecular weight polymers (M(n) <= 70,000 g mol(-1)) with reasonable MWD (M(w)/M(n) < 1.6) were synthesized by living ROP of epsilon-caprolactone using spirobititanocanes (2a, 2b) and titanocane 1c as initiators. The latter catalysts, according MALDI-TOF-MS data, afford poly(epsilon-caprolactone)s with almost equal content of alpha,omega-dihydroxyl- and alpha-hydroxyl-omega(carboxylic acid)-terminated chains arising due to monomer insertion into "Ti-O" bond of dialkanolamine ligand and from initiation via traces of water, respectively. (C) 2010 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 48: 1230-1240, 2010
- Добавил в систему: Карлов Сергей Сергеевич