Photoreversible gelation of a triblock copolymer in an ionic liquid.
Angew Chem Int Ed Engl
; 54(10): 3018-22, 2015 Mar 02.
Article
en En
| MEDLINE
| ID: mdl-25613353
The reversible micellization and sol-gel transition of block copolymer solutions in an ionic liquid (IL) triggered by a photostimulus is described. The ABA triblock copolymer employed, denoted P(AzoMA-r-NIPAm)-b-PEO-b-P(AzoMA-r-NIPAm)), has a Bâ
block composed of an IL-soluble poly(ethylene oxide) (PEO). The Aâ
block consists of a random copolymer including thermosensitive N-isopropylacrylamide (NIPAm) units and a methacrylate with an azobenzene chromophore in the side chain (AzoMA). A phototriggered reversible unimer-to-micelle transition of a dilute ABA triblock copolymer (1â
wt%) was observed in an IL, 1-butyl-3-methylimidazolium hexafluorophosphate ([C4mim]PF6), at an intermediate "bistable" temperature (50 °C). The system underwent a reversible sol-gel transition cycle at the bistable temperature (53 °C), with reversible association/fragmentation of the polymer network resulting from the phototriggered self-assembly of the ABA triblock copolymer (20â
wt%) in [C4 mim]PF6.
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Colección:
01-internacional
Base de datos:
MEDLINE
Idioma:
En
Revista:
Angew Chem Int Ed Engl
Año:
2015
Tipo del documento:
Article
Pais de publicación:
Alemania