Photoinduced Volume Transition in Liquid Crystalline Polymer Gels Swollen by a Nematic Solvent.
ACS Macro Lett
; 1(11): 1357-1361, 2012 Nov 20.
Article
em En
| MEDLINE
| ID: mdl-35607171
ABSTRACT
Nematic liquid crystalline (LC) cross-linked polymer gel sheets containing 3 mol % azobenzene (Az) unit were prepared and swollen by a nematic solvent of 4'-pentyl-4-cyanobiphenyl (5CB). This 5CB-swollen gel sheet exhibited a discontinuous volume change around the nematic-isotoropic phase transition temperature of the LC gel (TNIG). UV irradiation at a temperature slightly lower than TNIG provoked a large volume transition (expansion) due to a loss of nematic order within the gel sheet caused by the trans-to-cis photoisomerization of Az. The volume was reverted by irradiation with 436 nm light. By templating the colloidal crystal film of monodispersed silica particles, a LC gel sheet possessing a microporous structure was also prepared. Due to the facilitated diffusion of 5CB, the microporous LC gel exhibited significant enhancements in the extent and rate of the photoinduced volume transition.
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1
Coleções:
01-internacional
Base de dados:
MEDLINE
Idioma:
En
Revista:
ACS Macro Lett
Ano de publicação:
2012
Tipo de documento:
Article
País de afiliação:
Japão