A composite proton exchange membrane and method of manufacturing the same.
The composite proton exchange membrane comprises a proton exchange
membrane which has been modified by replacing membrane protons in desired
areas of the membrane with a cationic polymer. The cationic polymer is
preferably formed by introducing a quaternary salt monomer into the
membrane and then effecting the polymerization of the monomer. The
modified areas of the proton exchange membrane exhibit increased
strength, reduced water and gas permeability, reduced proton conductivity
and reduced acidity. Accordingly, by modifying the periphery of the
membrane, one can obtain an integral sealing edge for the membrane, and
by modifying certain interior regions of the membrane, one can divide the
membrane into a plurality of sealed segments.