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Molecular-level mixed matrix membranes made of polyimide/β-cyclodextrin (β-CD) for separating benzene/cyclohexane mixtures by pervaporation have been prepared and studied.2~20 wt.% of β-CD were dispersed in NMP solvent before polymerization.3,5-Diaminebenzoic acid (DABA) and 4,4’-diaminodiphenyl ether (ODA) were mixed with different ratios,then copolymerized respectively with 4,4-Oxydiphthalic anhydride (ODPA),3,3,4,4-Benzophenonetetracarboxylic dianhydride (BTDA) and 4,4-(Hexafluoroisopropylidene) diphthalic anhydride (6FDA) to give poly(amic acid)s which were converted into polyimides (PIs) by thermal imidization.The structures of these series of PIs were characterized by FT-IR,NMR,and XRD.The effect of β-CD content on the thermal stability,morphologies and surface energies was investigated by DSC,TGA,SEM and contact angle measurement.The separation efficiency of such membranes containing 2 to 10 wt.% of β-CD is superior over the same component neat polyimide membrane in terms of both flux and separation factor.With the increase of β-CD loading,the separation factor and permeation flux exhibited an increasing then decreasing trend.Comparing with the BTDA-PI and ODPA-PI,The 6FDA-ODA/DABA (1:1) polyimide containing equal β-CD content shows outstanding separation efficiency.A maximum separation factor of 10.1 with a corresponding flux of 0.86 kg·μm·m-2·h-1 for benzene/cyclohexane (50/50 wt.%) at 40°C was obtained at an optimal β-CD loading of 10wt.%.The newly developed mixed matrix membrane approach may open up a new way to prepare next-generation high-performance pervaporation membranes for benzene/cyclohexane separation.