2,3,3,3-tetrafluoroprop-1-ene (R1234yf) and trans-1,3,3,3-tetrafluoropropene (R1234ze(E)) as the promising refrigerants have attracted wide attention. To understand better of the refrigeration-cycle performance working with new refrigerants, the thermodynamic properties of refrigerant/oil mixtures should be well known, especially the viscosity of the refrigerant/oil mixture. Using a dual-capillary method, the viscosities were measured for POE75 saturated with R1234yf and R1234ze(E) from 303.15 to 348.15 K. The viscosity trends of R1234yf/POE75 and R1234ze(E)/POE75 mixtures are similar. As rising solubility, a sharp decrease of viscosity appeared firstly, and then it goes to be flat. Results show that the dissolved refrigerant in oil largely reduces the oil viscosity. Comparing to viscosity models including an empirical model (modified Setchenow-type equation) and Eyring's absolute rate theory coupled with three excess Gibbs energy models (Eyring-MTSM model, Eyring-NRTL model, and Eyring-wilson model), the Eyring-MTSM model give better results than the other studied models.

2,3,3,3-四氟丙烯-1-烯（R1234yf）和反式1,3,3,3-四氟丙烯（R1234ze（E））作为有前途的制冷剂引起了广泛的关注。为了更好地了解使用新制冷剂的制冷循环性能，制冷剂/油混合物的热力学性质应该是众所周知的，尤其是制冷剂/油混合物的粘度。使用双毛细管方法，测量从303.15到348.15 K饱和R1234yf和R1234ze（E）的POE75的粘度。R1234yf/ POE75和R1234ze（E）/ POE75混合物的粘度趋势相似。随着溶解度的增加，首先出现粘度的急剧下降，然后变为平坦。结果表明，溶解在油中的制冷剂大大降低了油的粘度。