| abstract |
The present invention discloses a grafted, asymmetric, porous, ultra-high molecular weight polyethylene film having a foaming point between about 78 psi and 160 psi. Monomers are grafted to the surface of the porous polymeric membrane, the monomers having one or more neutral groups or ion-exchange groups grafted to one or more surfaces of the membrane. The combination of two photoinitiators can be used to graft these monomers to the asymmetric, porous, ultra-high molecular weight film, resulting in water flow at a water flow rate of ungrafted, asymmetric, porous ultra-high molecular weight polyethylene film Graft microporous membranes at a rate of at least 50%. The graft film was also wetted in water. |