Počet záznamů: 1
Highly Branched Polyisobutylene by Radical Polymerization under Li[CB11(CH3)(12)] Catalysis
- 1.0386198 - ÚOCHB 2013 RIV US eng J - Článek v odborném periodiku
Volkis, V. - Shoemaker, R. K. - Michl, Josef
Highly Branched Polyisobutylene by Radical Polymerization under Li[CB11(CH3)(12)] Catalysis.
Macromolecules. Roč. 45, č. 23 (2012), s. 9250-9257. ISSN 0024-9297. E-ISSN 1520-5835
Výzkumný záměr: CEZ:AV0Z40550506
Klíčová slova: Dodecamethylcarba-closo-dodecaborate(-)Anion * polymerization * LiCB11(CH3)(12)
Kód oboru RIV: CC - Organická chemie
Impakt faktor: 5.521, rok: 2012 ; AIS: 1.237, rok: 2012
DOI: https://doi.org/10.1021/ma301850c
In the presence of a nonoxidizing radical initiator, azo-tert-butane, and a high concentration of LiCB11(CH3)(12), isobutylene undergoes thermal or light-induced radical polymerization to b-PIB, a highly branched polymer of modest molecular weight (mostly a few thousand and up to similar to 25 000 g/mol based on GPC with polystyrene standards). The structure of b-PIB was elucidated by NMR spectroscopy of a low-molecular-weight fraction. The polymer is branched on every carbon atom of the main chain; one chain end carries an isobutenyl group, and the other carries a tert-butyl group originating in the initiator. The branches are short segments of l-PIB (linear polyisobutylene), on the average composed of five IB units. A mechanism of formation if this dendrimer-like structure is proposed.
Trvalý link: http://hdl.handle.net/11104/0215648
Počet záznamů: 1