COMPOSITE MEMBRANE FOR GAS SEPARATION

摘要

PURPOSE:To obtain the title membrane having good air-permeability in the vertical direction and excellent tensile strength by laminating a membrane for gas separation on a porous supporting material which consists of both a dense layer and a porous layer arranged with fibrous reinforcing material in the inside and has 50-80% void. CONSTITUTION:For example, nonwoven fabric is fixed on glass plate and a polyethersulfone resin soln. is uniformly applied thereon and immersed into aqueous coagulating liquid together with the glass plate and peeled therefrom and washed with water and thereafter dried. Thereby the following porous supporting material 12 is obtained which consists of both a dense layer 12a having hole diameter of the surface not less than 0.5mum and a cavity layer 12b arranged with fibrous reinforcing material 12c in the inside and having hole diameter not less than 0.5mum and has 50-80% void. A composite membrane is obtained by laminating a membrane 11 for gas separation such as polydimethylsiloxane, polyhydroxystyrene and a copolymer of polysulfone on the porous supporting material 12. This composite membrane is excellent in air-permeability in the vertical direction and tensile strength and air leak is not caused even when it is bonded to a module frame.