Liquid-liquid equilibria of polyrotaxane and poly(vinyl alcohol)

Toshiyuki Kataoka, Yohei Nagao, Masatoshi Kidowaki, Jun Araki, Kohzo Ito

Research output: Contribution to journalArticlepeer-review

8 Citations (Scopus)


Liquid-liquid equillibria (LLE) of the tertiary system of hydroxypropylated polyrotaxane (HPPR)-poly(vinyl alcohol) (PVA)-solvent have been investigated by focusing on the internal structures of HPPR-PVA blend gels. The phase diagrams of the HPPR-PVA aqueous systems displayed two liquid phases at a high concentration and molecular weight of PVA. This result was consistent with the prediction of the Flory-Huggins lattice model. On the contrary, the HPPR-PVA-DMSO system exhibited only a single phase. The HPPR-PVA blend gels crosslinked in dimethylsulfoxide (DMSO) were highly transparent over a wide concentration range, while the gels prepared in water were opaque at high polymer concentrations. Spherical domains were observed in the opaque gels by laser scanning confocal microscopy, and the sizes of the domains were significantly dependent on the amount of cross-linking reagent utilized. These results indicated that the transparency of the HPPR-PVA blend gels was strongly affected by the competition between the liquid-liquid two-phase separation and the crosslinking HPPR and PVA polymers during the preparation of the blend gels.

Original languageEnglish
Pages (from-to)270-276
Number of pages7
JournalColloids and Surfaces B: Biointerfaces
Issue number1-2
Publication statusPublished - 2007 Apr 15
Externally publishedYes


  • Blend gel
  • Liquid-liquid equilibrium
  • Phase separation
  • Polyrotaxane
  • Slide-ring gel

ASJC Scopus subject areas

  • Biotechnology
  • Surfaces and Interfaces
  • Physical and Theoretical Chemistry
  • Colloid and Surface Chemistry


Dive into the research topics of 'Liquid-liquid equilibria of polyrotaxane and poly(vinyl alcohol)'. Together they form a unique fingerprint.

Cite this