(253b) Tuning Structure and Properties of Graded Triblock Terpolymer-Based Mesoporous Films

Phillip, W. A., University of Notre Dame
Mika Dorin, R., Cornell University
Wiesner, U., Cornell University
Hoek, E. M., University of California, Los Angeles
Elimelech, M., Yale University
Werner, J., Cornell University

This talk will focus on the fabrication and performance of ultrafiltration membranes made from multiblock polymers, whose self-assembled structure promises superior selectivity for separating viruses and other undesirable solutes from solution.  Despite considerable efforts towards fabricating ordered, water-permeable, mesoporous films from block copolymers, fine control over pore dimensions, structural characteristics, and mechanical behavior remains a major challenge. To this end, we describe the fabrication and performance characteristics of graded mesoporous and hybrid films derived from the newly synthesized triblock terpolymer, poly(isoprene-b-styrene-b-4-vinylpyridine). The film structure comprises a thin selective layer containing vertically aligned and nearly monodisperse mesopores at a density of more than 1014 per m2 above a macroporous support layer.  Solvent flow and solute separation experiments demonstrate that the terpolymer films have permeabilities comparable to commercial membranes, are stimuli-responsive, and contain pores with a nearly monodisperse diameter.  These results suggest that moving to multiblock polymers and their hybrids may open new paths to produce high performance graded membranes for a myriad of applications.