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Updated: Jun 29, 2026

Accurate Determination of the Equilibrium Surface Tension Values with Area Perturbation Tests
Published on: August 30, 2019
Origin of change in molecular-weight dependence for polymer surface tension
R B Thompson1, J R Macdonald, P Chen
1Department of Physics and Astronomy, University of Waterloo, Waterloo, Ontario, Canada N2L 3G1.
Abstract:
Self-consistent-field theory is used to reproduce the behavior of polymer surface tension with molecular-weight for both lower and higher molecular-weight polymers. The change in behavior of the surface tension between these two regimes is shown to be due to the almost total exclusion of polymer from the nonpolymer bulk phase. The predicted two regime surface tension behavior with molecular-weight and the exclusion explanation are shown to be valid for a range of different polymer compressibilities.
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