Tetrafluoroethylene / hexafluoropropylene copolymer and a production method thereof and a wire

The present invention relates to a tetrafluoroethylene / hexafluoropropylene copolymer and a production method thereof and an electric wire. The tetrafluoroethylene / hexafluoropropylene copolymer in the melt extrusion molding having improved moldability, in particular, defects can be significantly reduced in the high speed extrusion coating of wire in. The tetrafluoroethylene / hexafluoropropylene copolymer obtained by polymerization of at least tetrafluoroethylene selected from the group consisting of tetrafluoroethylene, hexafluoropropylene and a third monomer of the group consisting of hexafluoropropylene and obtained, with a melting point of not mixed with the tetrafluoroethylene / hexafluoropropylene copolymer melting point above 20 ℃ difference resins; melt viscoelasticity measurement at an ambient temperature of 310 deg.] C, an angular frequency of 0.01 rad / sec, the tetrafluoroethylene / six complex viscosity-hexafluoropropylene copolymer was 2.0 × 103Pa · s ~ 10.0 × 103Pa · s, a storage modulus of 0.1Pa ~ 3.5Pa. The tetrafluoroethylene / hexafluoropropylene copolymer useful as a coating on a conductive core in the wire.