NOVELTY - A fluorine-containing polymer is obtained by polymerizing perfluoro vinyl ether derivative (I). The polymer has melt viscosity of 5000 Pa.second or more at 0.1 radians/second and tan(delta) value of 2-50 at 0.1-1 radians/second, in dynamic viscoelasticity measurement at 270degreesC and 0.1-30% of distortion.    USE - For fluorine-containing compact which is a film used for solid polymer electrolyte type fuel cell (both claimed). Also used for electrolyte films for lithium cells, brine electrolysis, water electrolysis, hydrohalic acid electrolysis, film for oxygen enrichers, film for gas sensors and film for humidity sensors.    ADVANTAGE - The fluorine-containing polymer has high melt viscosity, moldability, and strength. The fluorine-containing compact obtained using the fluorine-containing polymer has favorable exterior and smooth surface.    DETAILED DESCRIPTION - A fluorine-containing polymer is obtained by polymerizing perfluoro vinyl ether derivative of general formula (I). The polymer has melt viscosity of 5000 Pa.second or more at 0.1 radians/second and tan(delta) value of 2-50 at 0.1-1 radians/second, in dynamic viscoelasticity measurement at 270degreesC and 0.1-30% of distortion.    Y1 = halogen or perfluoro alkyl group;    Y2 = halogen;    n = 0-3;    m = 1-5;    A1 = -SO2X1 or -COY3;    X1 = halogen, -OM1, -OM21/2 or -NR1R2;    M1 = H, NR3R4R5R6 or alkali metal;    M2 = alkaline earth metal;    R1,R2 = H, alkali metal, alkyl or sulfonyl-containing group;    R3-R6 = H or 1-4C alkyl;    Y3 = hydroxyl, -NR7R8 or 1-4C alkoxyl; and    R7,R8 = R1.    INDEPENDENT CLAIMS are included for the following:    (1) manufacture of fluorine-containing polymer which involves performing polymerization by carrying out additional preparation of perfluoro vinyl ether derivative of formula (I);    (2) fluorine-containing polymer derivative obtained by performing alkali hydrolysis or acid treatment of fluorine-containing polymer, and having sulfonic acid group which may form metallic salt;    (3) fluorine-containing compact which consists of fluorine-containing polymer and/or fluorine-containing polymer derivative; and    (4) solid polymer electrolyte type fuel cell having the fluorine-containing compact.    DESCRIPTION OF DRAWING(S) - The figure shows the chart for measuring frequency distribution of tan(delta) of the fluorine-containing polymer film of the example and comparative example. (Drawing includes non-English language text).