The invention is a material for a solid polyelectrolyte, comprising a
multi-segmented fluoropolymer that comprises a block copolymer and/or a
graft copolymer, wherein the copolymer contains one or more blocks
essentially consisting of segment A and one or more blocks essentially
consisting of segment B, the segment A combines with the segment B,
wherein the segment A has a molecular weight of 5,000 to 1,000.000, and
the Segment A is a copolymer chain comprising (a) an
ethylenicfluoromonomer containing sulfonic acid functional groups each
represented by Formula (1)
CX.sub.2.dbd.CX.sup.1--(O).sub.n--Rf--SO.sub.2Y, wherein X and X.sup.1
may be the same or different and are each hydrogen or fluorine; Y is FI,
Cl, or OY.sup.1 wherein y.sup.1 is hydrogen, alkali metal or
C.sub.1-C.sub.5 alkyl; Rf is C.sub.1 to C.sub.40 divalent fluoroalkylene
or C.sub.1 to C.sub.40 divalent fluoroalkylene having one or more ether
bonds; and n is 0 or 1; and (b) at least one type of ethylenic
fluoromonomer copolymerizable with the ethylenic fluoromonomer (a) and
containing no sulfonic acid functional groups, the segment B is a
fluoropolymer containing no sulfonic acid functional groups, has a
molecular weight of 3,000 to 1,200,000, and has a crystalline melting
point of 100.degree. C. or higher or a glass transition point of
100.degree. C. or higher, wherein the ratio of segment A:segment B in the
segmented fluoropolymer is 5:9.about.to 98:2 30:70 to 90:10 wt. %.