Preparation of jujube-cake structure membranes through in situ polymerization of hyperbranched polysiloxane in ethylene-vinyl acetate matrix for separation of ethyl acetate from water

Abstract

Ethylene-vinyl acetate (EVA)/hyperbranched polysiloxane (HPSiO) hybrid pervaporative membranes for separation of ethyl acetate (EA) from water with a “jujube-cake” structure were prepared by in situ polymerization. The morphology of the EVA/HPSiO membranes was characterized by using a scanning electron microscope (SEM) and transmission electron micrographs (TEM). The mechanical properties, contact angle, density, void volume and swelling behavior of the membranes were investigated. We also studied the effect of HPSiO content, operating temperature and feed concentration on the separation properties of EA/water mixtures. The results show that the addition of appropriate HPSiO could improve the hydrophobicity of the membranes, which is helpful to recover EA from water. The membrane, loading 20 wt% HPSiO, exhibited the highest separation factor and permeability for a feed concentration of 1 wt% at 30 °C.