Water: The Third Component in Polymer Two-Phase Systems

  • T. E. Treffry
  • T. H. Lilley
  • P. J. Cheek


Phase systems which are close to the critical point can be changed from biphase to monophase by increasing temperature or adding urea or water. Lower temperature or tert. Butanol have the opposite effect. These observations imply that water structure plays an important part in phase separation. Flow calorimetry of dextran and PEG solutions shows that these polymers are strongly solvated and that solute: solvent: solvent interactions are predominant in these systems. In mixing experiments the critical point appears thermochemically trivial and it is suggested that like polymer hydates form micro-phases at concentrations below the critical point.


Water Structure Guanidine Thiocyanate Polymer Hydrate Flow Calorimetry Lower Molecular Weight PEGs 


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Copyright information

© Plenum Press, New York 1989

Authors and Affiliations

  • T. E. Treffry
    • 1
  • T. H. Lilley
    • 2
  • P. J. Cheek
    • 2
  1. 1.Biochemistry DepartmentsUniversity of SheffieldSheffieldUK
  2. 2.Chemistry DepartmentsUniversity of SheffieldSheffieldUK

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