Oxygen‐enriching properties of a new hybrid membrane cross‐linked from PDMS and fluorine‐containing silicone resin

Abstract

A fluorine‐containing silicone resin substituent group,vinyl group, and inorganic framework (SR‐FVI) was synthesized through hydrolytic condensation by using vinyltriethoxysilane, 13‐fluorooctyltriethoxysilane, tetraethoxysilane, and tetramethyldivinyldisiloxane as monomers. A new cross‐linked hybrid membrane (CHM) was prepared with the hydrogen‐containing silicone oil (HSO) as a cross‐linking agent, polydimethylsiloxane containing vinyl group and the SR‐FVI as matrix materials to enhance its membrane‐forming ability and permselectivity. The membrane‐forming process and the cross‐linking reactions between the silicon–hydrogen bond and the vinyl group were carried out simultaneously at room temperature. The effects of the SR‐FVI content in the CHMs, pressure difference, and temperature on the oxygen‐enriching properties were evaluated and discussed. A good equilibrium between membrane‐forming ability and oxygen‐enriching properties was attained, for example, oxygen permeability coefficient and ideal separation factor of the CHM with the SR‐FVI content of 50 wt% at 20°C and 0.10 MPa were 594 Barrer and 3.50, respectively. Compared to cross‐linked PDMS membranes without the SR‐FVI, the CHMs show better gas selectivity and similar gas permeability. The oxygen‐enriching property is attributed to the fluorine‐containing component in the CHM due to its good oxygen solubility. POLYM. ENG. SCI., 53:2328–2335, 2013. © 2013 Society of Plastics Engineers