Khavunko O. Viscoelastic and dynamic properties of polystyrene in solutions and melts.

A dependence of the effective viscosity of diluted and concentrated solutions of polystyrene in toluene and also its melts on the hydrodynamic flow gradient rate has been investigated with the use of the rotary viscometer technique. It was proposed the fundamentally new approach to the analysis of these dependences based on the Maxwell's model. Using the optimization method of the experimental data it was marked out and numerically estimated the frictional and elastic components of the viscosity and it was investigated their dependence on the concentration of polystyrene in solution, molar mass and temperature. It have been calculated the activation energies, characteristic times of the segmental motion and dynamical properties of the polystyrene in solutions and melts. It was obtained the analytical expression for the characteristic viscosity of polymeric solution and it was shown, that the elastic component of the viscosity makes the main contribution into the characteristic viscosity of polymeric solution with taken into account its dependence on the hydrodynamic flow gradient rate.