| 摘要 |
PURPOSE:A crystal transparent copolymer for an optical fiber clad having a high softening temperature, excellent heat stability and moldability, obtained by controlling the content of a residual unreacted monomer of one component in a specified copolymer. CONSTITUTION:A copolymer is obtained by polymerizing (A) 40wt% or above fluoroalkyl methacrylate of the formula (wherein m is 1-2, n is 1-4 or 6-10, X is F, H, or Cl) with (B) 0.5-10wt% o-methylphenylmaleimide and (C) 1- 59.5wt% other copolymerizable monomer components [e.g., styrene, or (meth) acrylate esters]. A slurry of this copolymer in a solvent (e.g., methyl ethyl ketone) is extruded through a vented extruder, and the solvent and unreacted component B are removed to obtain a cladding copolymer of a content of residual unreacted component B<=0.1wt% which can give optical fiber having excellent light transmission performance, a high heat resistance temperature and nonadhering property. |
