CTFE/VCA/HFP OR TFE/VCA/HFP-BASED COPOLYMER, ITS PREPARATION METHOD, BODY CONTAINING THE COPOLYMER, MULTIMODE GRADED INDEX PLASTIC FIBER AND ITS PREPARATION METHOD

摘要

PURPOSE: Provided are a copolymer which is colorless and transparent in solution, is soluble in a common solvent, has a glass transition temperature more than 60 deg.C and has optical and thermomechanical properties suitable for the preparation of an optical fiber, a coating, a film and a photomask, its preparation method, a body containing the copolymer, a multimode graded index plastic optical fiber containing the copolymer, and its preparation method. CONSTITUTION: The copolymer comprises at least three units represented by the formulas P1, P2 and P3, wherein the content of the unit of P2 is 30-70 mol%, the content of the units of P1 and P3 is 30-70 mol%, and the copolymer has a weight average molecular weight of 10¬3 to 10¬6 g/mol. In the formulas, X1, X2 and X3 are identical or different one another and are H, F, Cl or Br; R1 is H, F, Cl or Br; R2 is a C1-C10 carbonaceous group containing totally or partially fluorinated carbon atoms; Y1 and Y2 which are identical or different each other, represent H, F, Cl, Br or a C1-C10 carbonaceous group; and Y3 is a carbonyl group or a divalent carbonaceous group.