TECHNOLOGY FOCUS - ELECTRICAL POWER AND ENERGY - Preferred System: The fuel cell system comprised of each of the cathode and the anode containing an electrode substrate and a catalyst layer. The fuel cell system further comprises a microporous layer disposed between the cathode or anode electrode substrate and catalyst layer. The fuel cell system comprises the fuel supplier containing a tank; and a pump. The fuel cell system comprises the oxidant supplier containing at least one pump.    TECHNOLOGY FOCUS - INORGANIC CHEMISTRY - Preferred Components: the radical polymerization initiator comprises peroxide-based compound, hydroperoxide-based compound and/or azo-based compound.    TECHNOLOGY FOCUS - ORGANIC CHEMISTRY - Preferred Components: The vinyl-based monomer comprises at least one of styrene, alpha-methyl styrene, 4-methylstyrene, 3,4-dichlorostyrene, methyl metacrylic acid, sodium acrylamide-tert-butyl sulfonate, polyaniline, polypyrrol, and poly thiophene. The anionic surfactant comprises at least one of alkyl fatty acid salt including 1-20C alkyl, alkylsulfonate including 1-12C alkyl, alcohol sulfuric acid ester salt including 1-12C alkyl and/or alkyl arylsulfonate including 1-12C alkyl. The proton-conductive polymer comprises at least one of poly(perfluorosulfonic acid), poly(perfluorocarboxylic acid), a copolymer of tetrafluoroethylene and fluorovinylether having a sulfonic acid group, defluorinated polyetherketone sulfide, aryl ketone having a proton-conductive functional group, poly(2,2'-(meta-phenylene)-5,5'-bibenzimidazole) having a proton-conductive functional group and/or poly(2,5-benzimidazole) having a proton-conductive functional group with the proton-conductive functional group selected from sulfonic acid, sulfonate, carboxylic acid, carboxylate, phosphoric acid, and phosphate.    TECHNOLOGY FOCUS - POLYMERS - Preferred Method: The method involves performing the emulsion polymerization at 0 - 50degreesC while dipping the proton-conductive polymer membrane in the emulsion polymerization solution. Preferred Components: The micelle has an average particle diameter of 1 nm - 10 microns. The vinyl-based polymer has an average molecular weight of 1000 - 100000. The polymer micelle is included into the proton-conductive polymer in an amount of 5 - 50 parts by weight based on 100 parts by weight of the proton-conductive polymer. EXAMPLE - Styrene (30 g), azobisisobutyronitrile (0.5 g) as a radical initiator, and dodecylbenzenesulfonic acid (10 g) as an anionic surfactant were put in deionized water (200 g) and mixed with it, thereby preparing an emulsion polymerization solution. Then, a 0.005 inch thick NAFION 115 (RTM: membrane) was dipped into the polymerization solution, so that it could be sufficiently swollen by the emulsion polymerization solution and permeated thereby. The swollen NAFION membrane was left in the emulsion polymerization solution at 30degreesC for 10 hours and then was washed, thereby preparing a test polymer electrolyte membrane. The same NAFION 115 membrane used above was used as a comparative polymer electrolyte membrane. Then, the fabricated test and comparative polymer electrolyte membranes for a fuel cell were evaluated regarding proton conductivity, swelling characteristics, and permeability by the over-crossed amount of methanol. The proton conductivity was measured by using a 2-probe type impedance analyzer, and the swelling characteristic was estimated by measuring weight change of distilled water after swelling. In addition, the permeability was estimated by measuring the over-crossed amount of methanol cross-over with a refractometer. The proton conductivity (S/cm); swelling characteristics (%); and permeability (cm2/s) for test/comparative polymer electrolyte membranes was found to be 0.19/0.1; 10/15; and 1.51.3 x 1025/1.3 x 1026 respectively. The test polymer electrolyte membrane turned out to have more excellent proton conductivity and swelling characteristic, and also had less methanol permeability than that of comparative membrane.