Process for preparing perfluoroalkyl vinyl ether copolymer and copolymer

A process for preparing a fluorinated polymer suitable for use in the formation of transparent optical fiber for use as a light transmission medium by copolymerizing (i) perfluoroalkyl vinyl ether represented by Formula 1 below:

• wherein RF is a fluorine atom or a C1˜5 perfluoroalkyl group;
• A is a single bond, —(CF2)n— in which n is an integer of 1 to 5, or —(CF2CRF2—O—CF2)— in which the substituents RF are each independently a fluorine atom or a C1˜5 perfluoroalkyl group;
• is a perfluoro cyclohexyl, perfluorophenyl, perfluorodioxanyl or perfluorodioxalanyl group,
• (ii) perfluorinated olefin monomer in a chlorofluorinated solvent in the presence of a periluorinated radical initiator, wherein the molar ratio of (i):(ii) is between 99:1 and 50:50, and
• (iii) a fluorinated monomer represented by Formula 5 below:
• wherein RF is a fluorine atom or a C1˜5 perfluoroalkyl group;
• and
• is a perfluoro cyclohexyl, perfluorophenyl, perfluorodioxanyl or perfluorodioxalanyl group, and wherein no C—H bonds are present in the resulting fluorinated polymer.