Thermodynamic properties of fluorinated ethers as alternative refrigerants.

The authors measured saturated vapor pressures from normal boiling point to critical temperature for 12 compounds and determined the critical temperatures and pressures for 10 compounds of a series of fluorinated ethers, which are expected to be promising candidates as advanced refrigerants. Wagner equation with 4 parameters was useful to correlate the vapor pressures in the wide temperature range. The group contribution method proposed by Lydersen could estimate the critical properties of the fluorinated ethers satisfactorily.