Coexistence curve for polystyrene–cyclohexane near the critical point

The coexistence curves for the system polystyrene–cyclohexane have been determined with a specially designed differential refractometer, which determines concentrations of the two coexisting phases with a precision of ± 0.01%. The plots of the coexistence curve data represented by log(X+−Xc) and log(Xc−X−) versus the reduced temperature e = (Tc−T)/Tc yield largely curved lines. The shape of the coexistence curve very near the critical point, however, is asymptotically symmetric. The coexistence curve obtained with an over‐all concentration at the critical concentration is represented by the relation X+−X− = Beβ with β=0.348 and B=0.97 in the temperature region of Tc −T<2.0 °C. The critical point exponent β and the coefficient B vary only slightly depending on the over‐all concentration. Although the data give a curved diameter, a precision of the present experiment is not sufficient to determine the asymptotic behavior of the diameter.

[1]  B. Chu,et al.  Coexistence curve of the polystyrene‐cyclohexane system in the critical region , 1973 .

[2]  Motozo Kaneko,et al.  Cloud-point curves of the polystyrene-cyclohexane system near the critical point , 1973 .

[3]  G. F. Allen,et al.  An Analysis of Coexistence Curve Data for Several Binary Liquid Mixtures Near Their Critical Points , 1973 .

[4]  J. L. Sengers,et al.  Coexistence Curves of CO2, N2O, and CClF3 in the Critical Region , 1971 .

[5]  N. Mermin.  Solvable Model of a Vapor-Liquid Transition with a Singular Coexistence-Curve Diameter , 1971 .

[6]  Per C. Hemmer,et al.  Fluids with Several Phase Transitions , 1970 .

[7]  R. Joseph,et al.  Scaled Equation of State and Critical Exponents in Magnets and Fluids , 1970 .

[8]  John S. Rowlinson,et al.  New Model for the Study of Liquid–Vapor Phase Transitions , 1970 .

[9]  J. L. Sengers,et al.  Thermodynamic Anomalies ofCo2, Xe, andHe4in the Critical Region , 1969 .

[10]  F. Hynne,et al.  Coexistence Curve for 3‐Methylpentane–Nitroethane near the Critical Point , 1969 .

[11]  P Heller,et al.  Experimental investigations of critical phenomena , 1967 .

[12]  A. J. Staverman,et al.  Liquid-liquid phase separation in multicomponent polymer solutions , 1967 .

[13]  D. Möller,et al.  Entmischungserscheinungen in lösungen von molekularuneinheitlichen hochpolymeren , 1965 .

[14]  O. K. Rice,et al.  Shape of the Coexistence Curve in the Perfluoromethylcyclohexane-Carbon Tetrachloride System. II. Measurements Accurate to 0.0001° , 1964 .

[15]  O. K. Rice,et al.  Shape of the Coexistence Curve in the Perfluoromethylcyclohexane‐Carbon Tetrachloride System , 1955 .

[16]  B. Zimm.  The Shape of the Coexistence Curve in the Critical Region , 1952 .

[17]  B. A. Brice,et al.  A differential refractometer. , 1951, Journal of the Optical Society of America.

[18]  B. Zimm.  Opalescence of a two-component liquid system near the critical mixing point. , 1950, The Journal of physical and colloid chemistry.

[19]  E. A. Guggenheim.  The Principle of Corresponding States , 1945 .

[20]  P. Flory.  Thermodynamics of High Polymer Solutions , 1941 .

[21]  N. A. Sörensen,et al.  Studies of Critical Phenomena in Carbon Dioxide contained in Vertical Tubes. , 1953 .