Jump to main content
Jump to site search


Unusual photoresponses in the upper critical solution temperature of polymer solutions mediated by changes in intermolecular interactions in an azo-doped liquid crystalline solvent

Author affiliations

Abstract

Photoinduced changes in the upper critical solution temperature (UCST) were investigated for polymer solutions in an azobenzene-doped liquid crystal solvent. The UCST of poly(methyl methacrylate) (PMMA) and polystyrene (PS) solutions dropped upon irradiation with UV light, which induces transcis photoisomerization of the doped azo dye. In the case of PMMA solutions, the photoinduced drop in UCST was significantly larger than that expected from previous studies using azo-based polymers and common solvents. Moreover, the UCST of PS solutions also decreased under photoirradiation, in a direction opposite to that expected from the contribution of polarity. X-ray diffraction data of the solvent suggest that the decreased intermolecular interaction in the solvent (i.e. larger distance between the solvent molecules) is responsible for the photoresponsive behavior of the UCST. The proposed mechanism is consistent with the Flory–Huggins theory. Using such photoresponses in the UCST, the isothermal transition between 2-phase and 1-phase states by photoirradiation was demonstrated.

Graphical abstract: Unusual photoresponses in the upper critical solution temperature of polymer solutions mediated by changes in intermolecular interactions in an azo-doped liquid crystalline solvent

Back to tab navigation

Supplementary files

Publication details

The article was received on 13 Dec 2017, accepted on 19 Jan 2018 and first published on 22 Jan 2018


Article type: Paper
DOI: 10.1039/C7CP08335A
Citation: Phys. Chem. Chem. Phys., 2018, Advance Article
  •   Request permissions

    Unusual photoresponses in the upper critical solution temperature of polymer solutions mediated by changes in intermolecular interactions in an azo-doped liquid crystalline solvent

    Y. Kawata, T. Yamamoto, H. Kihara, Y. Yamamura, K. Saito and K. Ohno, Phys. Chem. Chem. Phys., 2018, Advance Article , DOI: 10.1039/C7CP08335A

Search articles by author

Spotlight

Advertisements