Various embodiments demonstrate that an in-situ polymerization enables deposition of a homogeneous polyaniline layer with a controlled thickness on top of a porous polypropylene support. Photografting and subsequent modification with diamines affords composite membranes featuring both high permeability and selectivity that are well suited for applications such as separation of carbon dioxide from a natural gas.
STATEMENT OF GOVERNMENTAL SUPPORT
 The invention described and claimed herein was made in part utilizing funds supplied by the U.S. Department of Energy under Contract No. DE-AC02-05CH11231 between the U.S. Department of Energy and the Regents of the University of California for the management and operation of the Lawrence Berkeley National Laboratory. The government has certain rights in this invention.