| 摘要 |
PROBLEM TO BE SOLVED: To obtain a transparent fiber having excellent high-temperature strength and light-transmitting properties and useful for a core material of optical fiber, etc., by melt-spinning a copolymer containing an acrylic monomer, etc., and polymerizable monomer having alkoxysilyl group and curing the fiber with moisture. SOLUTION: This transparent fiber having a glass transition temperature of >=110 deg.C, a yield point of >=50kgf/cm<2> at 110 deg.C and a breakage strength of >=90kgf/cm<2> is produced by crosslinking a copolymer containing an acrylic and/or styrene-based monomer and a polymerizable monomer having an alkoxysilyl group as essential monomer units and having recurring units of formula I [R<1> is H or methyl; R<2> is COOR<4> (R<4> is a 1-6C chain alkyl, etc.), phenyl or CN] and formula II (R<3> is direct bond, etc.; R<6> is H or a 1-5C alkyl; R<7> is H, an alkyl, etc.; (a) is 0 or 1) with a siloxane bond, melt-spinning the produced copolymer having crosslinked structure and curing the spun fiber with moister in an atmosphere of 20-100 deg.C and a relative humidity of 40-100%RH. |
