Importance

Loading Importance Indicators...

Abstract

A composite membrane comprises a substrate made from a polymer selected from copolymers and homopolymers of ethylenically unsaturated nitriles, which substrate has preferably first been treated with a pore protector in absence of curing agents and catalysts therefor, prior to applying as the final coating a silicone layer, which is crosslinked. The pore protector, which may be, for example, a hydroxy-terminated polysiloxane, particularly a silanol-terminated polysiloxane, serves the dual purpose of preventing the pores from collapsing, when the support is dried during the curing of the silicone layer, and of preventing passage of the coating material deeply into the pores and thus also preventing an undue reduction of the flux of the finished coated membrane. Such composite membranes include solvent stable membranes which swell to an extent of no more than about 10% when immersed in various organic solvents, and their mixtures with each other and/or water.

Loading the Abstract Image...

First Claim