segmental motion

We studied the gradient dependence of the effective viscosity η for the diluted solution of the polystyrene in toluene under three concentrations ρ = 0.5∙105, 1∙105 and 2∙105 g/m3 and for four polystyrene fractions with average molar weights М = 5.2∙104, 4.4∙104, 3.3∙104 and 1.8∙104 g/mol, in the temperature range of 293–308 K. The experiments have been carried out with the use of rotary viscometer “Rheotest 2.1” at various cylinder rotation angular rate ω (r/s).

An analysis of the characteristic times of the polystyrene segmental motion estimated on the basis of the elastic and frictional viscosity components of the polystyrenes solutions has been done. The characteristic times of the translational motion and also the diffusion coefficients of polystyrene in diluted and concentrated solutions were calculated.