Three representative activity coefficient models were compared for the calculation of the thermodynamic factor relating self-to mutual-diffusion coefficients of polymer solutions using the experimental data of40polymer solution systems.The calculated results show that the three models have similar accuracy

and the AADs are around20%.This work shows a potential problem in the calculation of mutual-diffusion coefficients from self-diffusion coefficients

that is

the big uncertainty caused by the calculation of the thermodynamic factor with an activity coefficient model.