IUPAC-NIST Solubilities Database

IUPAC-NIST Solubility Database
NIST Standard Reference Database 106

Solubility System: Methane with Tetramethylhexafluorpolycarbonate (TMHFPC)

Components:
   (1) Methane; CH4; [74-28-8]  NIST Chemistry WebBook for detail
   (2) Tetramethylhexafluropolycarbonate (TMHFPC); ; [125431-72-3]  NIST Chemistry WebBook for detail

Original Measurements:
   D.S. Pope, G.K. Feming and W.J. Koros, Macromolecules 23, 2988 (1990).

Variables:
   Temperature = 308 K
   Pressure = 0-3 MPa

Prepared By:
   Yu. P. Yampol'skii

Experimental Data:   (Subscripts 1,2,3, ..., in column headings refer to components 1,2,3, ...)

Sorption isotherms of methane at 308 K in unconditioned conventionally conditioned, and exchange-conditioned samples of TMHFPC (The original data were represented graphically)
Pressure [MPa]	Sorption [(V₁(STP)/V₂)]	Remark(s)
0.20	3.51	Unconditioned
0.60	8.50	Unconditioned
1.05	12.66	Unconditioned
1.61	16.39	Unconditioned
2.23	20.03	Unconditioned
2.94	23.33	Unconditioned
0.70	11.09	Conventionally conditioned
1.41	17.75	Conventionally conditioned
2.12	22.64	Conventionally conditioned
2.72	26.45	Conventionally conditioned
0.34	7.02	Exchange-conditioned
0.71	12.18	Exchange-conditioned
1.23	17.93	Exchange-conditioned
1.75	22.42	Exchange-conditioned
2.23	25.65	Exchange-conditioned
2.69	28.38	Exchange-conditioned

Method/Apparatus/Procedure:
   Two methods of conditioning were studied. Conventionally conditioned isotherm were obtained with the samples which had been previously in contact with CO₂ gas under pressure of 6.2 MPa for 2—3 h with consequent pumping for 2 days. Exchange conditioning involves exposing samples to CO₂ gas and then sweeping it with a methane flux. For exchange conditioning runs a gravimetric technique was used. In two other types of experiments a pressure decay method was applied.¹

Source and Purity of Materials:
   CH₄: purity >99.99 %. TMHFPC: synthesized, density 1.200 g/cm³, glass transition temperature 481 K.

Estimated Errors:

   Temperature: No information given.

References:
   ¹W. 3. Koron and D. R. Paul, J. Polym. Sci., Polym. Phys. Ed. 14, 1903 (1976).