Cross-linked HTPB-based polyurethaneurea membranes for recovery of ethyl acetate from aqueous solution by pervaporation

Cross-linked hydroxy terminated polybutadiene (HTPB)-based polyurethaneurea (PU), HTPB–DVB–PU, was synthesized by a three-step polymerization process. It was firstly used as membrane material to recover aroma, ethyl acetate (EA), from aqueous solution by pervaporation (PV). The effects of the content of cross-linker DVB, EA concentration in feed, and operating temperature on the PV performance of HTPB–DVB–PU membranes were investigated. The membranes demonstrated high EA permselectivity as well as high total flux. The introduction of DVB significantly enhanced the temperature resistance ability of the HTPB–DVB–PU membranes. With increasing DVB content, the separation factor increased while the total flux decreased a little. The best PV performance, separation factor and total flux were 655 and 256 g/m2 h, respectively with feed concentration of 2.5 wt% EA at 30 °C. These PV performances with increasing DVB content were explained in terms of the viewpoint of chemical compositions and physical structures of the HTPB–DVB–PU membranes.