Physical property measurements are presented for 24 fluorinated propane and butane derivatives and one fluorinated ether. These measurements include melting point, boiling point, vapour pressure below the boiling point, heat of vaporisation at the boiling point, critical properties (temperature and density), and liquid-phase heat capacities at 40 deg C (104 deg F). Measured vapour pressures are obtained up to the critical temperature for four of the compounds - R227ea, R245cb, R236ea (all HFCs), and R125a (an HFE). These measured data, combined with estimated vapour-phase densities, heat capacities, and vapour pressures, may be used to evaluate the chemicals as alternative refrigerants. Modified corresponding states methods, using R134a (an HFC) as a reference fluid, are presented as a means of obtaining the needed estimated data, and the accuracy of these methods is judged by comparisons with measured data.

KEYWORDS: properties, fluorocarbons, refrigerants, R227ea, R245cb, R125a, measuring, calculating, density, thermal capacity, vapour pressure, accuracy, comparing.