Polyether-block-amide (Pebax)/glycerol triacetate (GTA) blend membranes with various compositions were prepared with a solution-casting method. The gas-separation performance, thermal stability, and storage stability of the prepared membranes were investigated at different pressures and temperatures. The Arrhenius equation was used to describe the gas-permeation performance of the Pebax1074/GTA membranes with a low GTA concentration (<= 40 wt %) rather than those membranes with a high GTA concentration (>40 wt %). A higher GTA content, lower treatment temperature, and storage temperature increased the gas permeability and induced a stronger hydrostatic pressure effect. The low-storage temperature was beneficial for fixing GTA on the blend membrane. (c) 2019 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2019, 136, 47620.