FINITE AND INFINITE DILUTION ACTIVITY-COEFFICIENTS IN POLYCARBONATE SYSTEMS

Measurements of activity coefficients at infinite dilution in bispheno l-a-polycarbonate were carried out for a series of alkanes (C-8,C-9,C1 0C12), alcohols (C-3-C-10) and aromatics (toluene, ethylbenzene, propy lbenzene, o-, m-, p-xylene, chlorobenzene, o-dichlorobenzene) at 160 d egrees C, 180 degrees C and 200 degrees C using the inverse gas chroma tography. Applying a gravimetric method, the solubilities of different solvents (chlorobenzene, toluene, ethylbenzene, m-xylene, p-xylene an d mesitylene) in the same polymer were measured. To model the absorpti on data the SAFT equation of state was used. For this purpose the pure -component parameters of the polymer had to be adjusted to the binary data of one polycarbonate-solvent system. Using these parameters for t he polymer, the experimental data of the other systems could be descri bed well, too. (C) 1997 Elsevier Science B.V.