6533b835fe1ef96bd129e9af

RESEARCH PRODUCT

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Phase diagrams were calculated for flowing solutions of polystyrene in trans-decahydronaphthalene assuming that the energy (Es) stored in the sheared state has to be added to the Gibbs energy of mixing; Es is computed from viscometric data (flow curves). The resulting phase diagrams exhibit two maxima in most of the cases instead of only one for the stagnant solutions. A comparison with experimental data (Part 1) shows that the calculated demixing behaviour agrees well for moderate shear rates and concentrations of the polymer. Deviations in the semidilute region, particularly for higher values, are a consequence of the fact that so far no reliable theoretical relation has been given for these conditions to calculate Es from viscometric data. In all cases, however, the present attempt describes the characteristics of the phase diagrams very well, namely the eulytic points and the inversion of shear dissolution into shear demixing.