Activator Generated Electron Transfer Combined Atom Transfer Radical Polymerization (AGET-ATRP) for Controlled Grafting Location of Glycidyl Methacrylate on Regenerated Cellulose Ultrafiltration Membranes

This investigation indicates the ability to selectively graft glycidyl methacrylate (GMA) only from the external surface of regenerated cellulose (RC) ultrafiltration (UF) membranes using activator generated electron transfer (AGET) atom transfer radical polymerization (ATRP). This controlled polymerization resulted in epoxy functionalized polymer brush ends. Further reaction of the terminal epoxy groups provides a flexible platform to introduce desired functionalities either by electrophilic or nucleophilic epoxy ring opening. Selective grafting from the external membrane surface was achieved by using an appropriate pore filling solvent prior to modification. A high viscosity pore filling solvent that is immiscible with the reactive monomer solution used during surface modification was the most effective in supressing grafting from the internal pore surface. The effects of grafting on membrane performance were evaluated by determining water permeability and protein rejection.