Estimation of the η parameter for poly (dimethylsiloxane) solutions by the UNIFAC group contribution method Academic Article uri icon


  • The UNIFAC group contribution method is used to calculate the reduced residual chemical potential x for poly (dimethylsi1oxane) solutions in alkanes, aromatic hydrocarbons, and dimethylsiloxane oligomers. The correct dependence of x on polymer segment fraction is obtained for all solvents. In most cases the computed value of x differs by less than 10% from the experimental data. No adjustable parameters or solution data are required for the calculation. The UNIFAC method is shown to be a promising tool for systems with small “free volume” effects and unavailable experimental data. The thermodynamics of polymer solutions have attracted the interest of many investigators. Several theories have been put forward in an effort to explain the various phenomena occurring when large polymer molcules are mixed with small solvent rnolecule~.~-~ Traditionally, the chemical potential …

publication date

  • January 1, 1981