High-pressure volumetric behavior of x 1,1,1,2-tetrafluoroethane plus (1-x) 2,5,8,11,14-pentaoxapentadecane (TEGDME) mixtures

This paper reports 1017 new pVT measurements of the x 1,1,1,2-tetrafluoroethane(HFC-134a) +(1 - x) 2,5,8,11,14-pentaoxapentadecane (TEGDME) system for x = 0.0, 0.1114, 0.2896, 0.3648, 0.5702, 0.6931, 0.7288, 0.8727, 0.9290, and 1 between 10 and 60 MPa in the temperature range 293.15 K to 373.15 K at 5 MPa and 10 K intervals, respectively. In almost all the measurement range, the density of the pure compressed refrigerant is greater than that of the pure polyether. For temperatures higher than 343.15 K, the isocomposition curves for the mixtures show an intersection point. Similar behavior has been previously found for HFC-134a + triethylene glycol dimethyl ether, carbon dioxide + alkane or toluene systems, and mixtures of R-410A with polyolester lubricants. The excess molar volume is negative over the whole composition range at all temperatures and pressures.