Journal of Chemical and Engineering Data, Vol.55, No.8, 2781-2785, 2010
Determination of Phase Equilibrium (Solid-Liquid-Gas) in Poly-(epsilon-caprolactone)-Carbon Dioxide Systems
Solid-liquid-gas equilibrium of poly-(epsilon-caprolactone)-carbon dioxide systems at high pressure has been determined by visual determination of the first melting point using a static apparatus. Measurements have been performed with poly-(epsilon-caprolactones) of three different molecular weights: 4000 g.mol(-1), 10 000 g . mol(-1), and 25 000 g . mol(-1). The determined SLG equilibrium lines show a temperature maximum at low pressures (0.5 Pa < P < 1.6 MPa) and a temperature minimum at moderate pressures (8 MPa < P < 10 MPa). The maximum reduction of melting temperature ranges from (12.5 to 16.0) K depending on the molecular weight of the polymer. A thermodynamic model based on the PC-SAFT equation of state has been developed to describe experimental data.