3D nanostructured materials, an application for a gas separation membranes

Abstract

In an effort to make a very efficient gas separation membrane, a three dimensional composite structure of very thin polypyrrole (PPy) nanotube array was fabricated. A very thin PPy film was polymerized using the interfacial polymerization technique inside the pores of a polycarbonate track-etched membrane, which results in a very thin membrane with a large surface area. After removing of polycarbonate template, polydimethylsiloxane (PDMS) polymer which is very permeable was coated on both sides of the polypyrrole nanotube array to increase mechanical strength. Gas separation characteristics of this PDMS / PPy nanotube array was measured with constant volume method. The permeability of this membrane for oxygen was about 220barrers and for the nitrogen was about 12barrers with O2/N2 selectivity of 18.3. However, reproducibility of the fabrication is still a problem.