摘要：

Experimental data from hydrodynamic measurements on eleven standard polystyrene samples in a poor and a good solvent (cyclohexane at theta-temperature 34,5°C, toluene at 25°C) are analyzed in terms of the two-parameter theory of the hydrodynamic properties of random coils. The discussion is focussed on the expansion factors of hydrodynamic radii α f and α μ , evaluated from the translation friction coefficients and the intrinsic viscosity, and on the hydrodynamic-interaction parameters P and Φ . The expansion factors α f and α η are shown to assume nearly equal values (at 1,15 ≤α η ≤ 1,5). That implies that the dependences on coil expansion must be very similar for P and Φ 1/3 . The value of the P parameter in the unperturbed state (i.e. P 0 ) is shown to be close to that recently calculated by Zimm and to be significantly higher than the results of previous theoretical calculations.

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