Abstract: The present invention provides a semipermeable membrane having enhanced alkaline stability and a method of forming a semipermeable membrane having enhanced alkaline stability, comprising steps of: providing an ultrafiltration (UF) base membrane, immersing said UF membrane in a solution comprising at least one substance selected from the group consisting of a polymer preferably polyethylenimine (PEI), a condensate solution and a mixture thereof, thereby forming reactive moieties upon said UF membrane, and forming at least one first layer upon at least portion of said UF base support membrane by immersing said UF base support membrane of step (b) in a solution comprising at least one ingredient selected from the group consisting of polymer preferably polyethylenimine (PEI), condensate solution and a mixture thereof thereby forming a cross-linked skin on the surface of said base membrane.

Abstract: The present invention provides a semipermeable membrane having enhanced alkaline stability and a method of forming a semipermeable membrane having enhanced alkaline stability, comprising steps of: providing an ultrafiltration (UF) base membrane, immersing said UF membrane in a solution comprising at least one substance selected from the group consisting of a polymer preferably polyethylenimine (PEI), a condensate solution and a mixture thereof, thereby forming reactive moieties upon said UF membrane, and forming at least one first layer upon at least portion of said UF base support membrane by immersing said UF base support membrane of step (b) in a solution comprising at least one ingredient selected from the group consisting of polymer preferably polyethylenimine (PEI), condensate solution and a mixture thereof thereby forming a cross-linked skin on the surface of said base membrane.

Abstract: Solvent and acid stable ultrafiltration and nanofiltration membranes including a non-cross-linked base polymer having reactive pendant moieties, the base polymer being modified by forming a cross-linked skin onto a surface thereof, the skin being formed by a cross-linking reaction of reactive pendant moieties on the surface with an oligomer or another polymer as well as methods of manufacture and use thereof, including, inter alia separating metal ions from liquid process streams.

Abstract: Solvent and acid stable ultrafiltration and nanofiltration membranes including a non-cross-linked base polymer having reactive pendant moieties, the base polymer being modified by forming a cross-linked skin onto a surface thereof, the skin being formed by a cross-linking reaction of reactive pendant moieties on the surface with an oligomer or another polymer as well as methods of manufacture and use thereof, including, inter alia separating metal ions from liquid process streams.