TECHNOLOGY FOCUS - ORGANIC CHEMISTRY - Preferred Components: The initiator of a perfluoro compound is a perfluorobenzoyl peroxide.    TECHNOLOGY FOCUS - POLYMERS - Preferred Method: The method further comprises subjecting the copolymer to fluorination with fluorine gas alone or diluted with an inert gas at 150-200 (preferably 170-190) degrees C. The polymer obtained by the copolymerization of the monomer of the 1,1,2,2-tetrafluoro-2-pentafluoroallyloxy-ethanesulfonyl fluoride and tetrafluoroethylene, has T(Q) of 200-400 degrees C, while T(Q) indicates a temperature at which, when melt-extrusion of the resin is carried out using a nozzle having a length of 1 mm and an inner diameter of 1 mm under an extrusion pressure condition of 30 kg/cm2 , the extrusion rate would be 100 mm3/sec, and is obtained by hydrolysis of the polymer followed by conversion to an acid-form. In the method, T(Q) is at most 350 (preferably 300) degrees C. Preferred Components: The copolymer additionally comprises a minor amount of repeating units based on another fluorinated monomer. The copolymer has a perfluoro structure. EXAMPLE - 1,1,2,2-Tetrafluoro-2-pentafluoroallyloxy-ethanesulfonyl fluoride (37.2 g) and perfluorobenzoyl peroxide (205 mg) as an initiator, were introduced into a autoclave and cooled with liquid nitrogen and deaerated. Then, tetrafluoroethylene was introduced into the autoclave and the system was maintained at 80 degrees C under 0.345 MPaG for 2 hours and 50 minutes. The autoclave was cooled and the gas in the system was purged to stop the polymerization. After diluting with hydrochlorofluorocarbon-225cb, the polymer was flocculated by an addition of hydrochlorofluorocarbon-141b, followed by filtration. Then, the polymer was stirred in hydrochlorofluorocarbon-225cb and re-flocculated by hydrochlorofluorocarbon-141b, followed by vacuum drying overnight at 80 degrees C to obtain the electrolyte polymer material having ion exchange capacity of 1.12 meq/g and T(Q) of 204 degrees C, while T(Q) indicates a temperature at which, when melt-extrusion of the resin was carried out using a nozzle having a length of 1 mm and an inner diameter of 1 mm under an extrusion pressure condition of 30 kg/cm2.