Epoxide-based PDMS membranes with an ultrashort and controllable membrane-forming process for 1-butanol/water pervaporation

Abstract

The ultrashort and controllable membrane-forming process is highly required in large-scale production of PDMS membrane. To shorten the cross-linking time, an UV-induced ring-opening polymerization of the epoxide groups was introduced to the preparation of PDMS membranes. PDMS was firstly functionalized with epoxide groups, providing the possibility of being cross-linked under UV irradiation. With this strategy, the membrane curing was finished within 200 s, hence shortened by two orders of magnitude in comparison with the conventional thermal-driven method. Meanwhile, the cationic photoinitiation of epoxide groups can be achieved without oxygen inhibition in an open-air environment. Moreover, the viscosity of the coating solution in the groove is kept constant when protected from light, thus meeting the requirement of the coatability. When applied to the pervaporation of a 1.5 wt% 1-butanol/water solution at 55 °C, the measured 1-butanol separation factor was 45 and the total flux was 1119 g m−2 h−1. This novel strategy shows a great prospect in the continuous preparation of membrane.