1-Ethyl-3-methylimidazolium hexafluorophosphate ([Emim][PF6]) was incorporated into poly(amide-6-b-ethylene oxide) (Pebax1657) to prepare blend membranes. The physical properties of Pebax1657/[Emim][PF6] blend membranes were characterized by Fourier transform infrared spectroscopy (FTIR), differential scanning calorimetry (DSC) and scanning electron microscopy (SEM). For Pebax1657/[Emim] [PF6] blend membranes, the melting peak of polyether (PE) segment disappeared when [Emim][PF6] content reached 10 wt%, and the melting peak of [Emim][PF6] appeared until [Emim][PF6] content came up to 60 wt%, indicating the homogeneous mixing of [Emim][PF6] and Pebax1657 for the prepared Pebax1657/ [Emim][PF6] blend membranes. According to FTIR, some interactions were formed between [Emim][PF6] and PE segment. The gas transport properties of CO2, N-2, CH4 and H-2 for Pebax1657/[Emim][PF6] blend membranes were also investigated. The incorporation of [Emim][PF6] increased the gas solubility coefficients of CO2, N-2, CH4 and H-2, however the gas diffusion coefficients decreased, which led to the decrease of the permeabilities of CO2, N-2, CH4 and H-2. Meanwhile, the selectivity of CO2/CH4 increased slightly. With the increase of temperature (35-85 degrees C), the solubility coefficient of CO2 decreased, while the diffusion coefficients of CO2, N-2, CH4 and H-2 increased, resulting into the increase of the permeabilities of CO2, N-2, CH4 and H-2. Moreover, no sharp increase of gas permeability was observed at the melting point of [Emim][PF6] (60 degrees C). And the activation energies of permeation of CO2, N-2, CH4 and H-2 increased with increasing [Emim][PF6] content. (C) 2017 Elsevier B.V. All rights reserved.