Surface tension measurements of 1,1,1,3,3-pentafluoropropane (HFC-245fa) and 1,1,1,3,3,3-hexafluoropropane (HFC-236fa) from 254 to 333 K

The surface tension of 1,1,1,3,3-pentafluoropropane (HFC-245fa) and 1,1,1,3,3,3-hexafluoropropane (HFC-236fa) were measured over the temperature range of 254–333 K, using the differential capillary rise method (DCRM) under vapor–liquid equilibrium conditions. The temperature and surface tension uncertainties were estimated to be within ±10 mK and ±0.15 mN m−1, respectively. The present data were used to develop van der Waals-type surface tension correlations for HFC-245fa and HFC-236fa, respectively.