THE PERMEABILITY BEHAVIOR OF POLYVINYLPYRROLIDONE-MODIFIED POROUS SILICA MEMBRANES

The surface of 4100 Angstrom-pore-size silica membranes was modified w ith a covalently bonded polyvinylpyrrolidone brush layer by a novel gr aft polymerization process. Hydraulic permeability measurements perfor med with six different solvents and both unmodified and modified membr anes suggest that the permeability of the modified membrane is determi ned by the configuration of the terminally anchored polymer chains. In the modified ceramic-supported polymeric (CSP) membrane, the swelling of the polymer brush layer increases as the solvent power increases, resulting in a decrease in the pore radius and subsequently, the perme ability.