| 摘要 |
PURPOSE:To prevent a copolymer from being made cloudy and reduce residual monomer amount sufficiently by specifying the conditions for polymerization and de-monomer in the copolymer containing, as essential components, a long chain fluoroalkylmetaacrylate and N-alkylmaleimid. CONSTITUTION:A copolymer containing a fluoroalkyl (meta) acrylate unit in formula I of 20 to 99.8% by weight, a fluoroalkyl (meta) acrylate unit in formula II of 0 to 70% by weight, and an N-(fluoro) alkylmaleimid unit in formula III of 0.2 to 30% by weight is polymerized and then de-monomered. In this case, the polymerization is made under the condition that batch polymerization completes at a polymerization rate of 70% or below, and then a connected part and de-monomered part are passed continuously to provide a colorless transparent clad material with a residual monomer rate of 0.5% or below. Where, in equations I to III, X1 is CH3, etc., n is 1 or 2, X2 is H, etc., and R1 is methyl, etc. Also m in formula I is the integer of 4 to 10 and m in formula II is the integer of 0 to 3. |
