METHACRYLIC COPOLYMER AND ITS PRODUCTION METHOD, PLASTIC OPTICAL FIBER, PLASTIC OPTICAL FIBER CABLE, AND PLASTIC OPTICAL FIBER CABLE WITH PLUG

摘要

PROBLEM TO BE SOLVED: To stably and easily produce a methacrylic copolymer which is suitable as a core material of a plastic optical fiber and has a high refractive index and excellent optical characteristics while inhibiting the change in copolymer composition. SOLUTION: In producing a copolymer of methyl methacrylate and benzyl methacrylate, raw materials including a monomer mixture comprising 0.1-99.9 mass% methyl methacrylate and 0.1-99.9 mass% benzyl methacrylate (the total amount of monomers being 100 mass%) and a free-radical polymerization initiator and if necessary further including a solvent are subjected to bulk polymerization or solution polymerization at 120-170 deg.C to give a copolymer composition having a copolymer content of 30-70 mass%; then, volatile components are separated and removed from the copolymer composition.