Finite and infinite dilution activity coefficients in polycarbonate systems

Measurements of activity coefficients at infinite dilution in bisphenol-a-polycarbonate were carried out for a series of alkanes (C8,C9,C10,C12), alcohols (C3C10) and aromatics (toluene, ethylbenzene, propylbenzene, o-, m-, p-xylene, chlorobenzene, o-dichlorobenzene) at 160°C, 180°C and 200°C using the inverse gas chromatography. Applying a gravimetric method, the solubilities of different solvents (chlorobenzene, toluene, ethylbenzene, m-xylene, p-xylene and mesitylene) in the same polymer were measured. To model the absorption 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 the polymer, the experimental data of the other systems could be described well, too.