PURPOSE: To obtain the subject acrylic fiber by adding a monomer containing sulfonic acid group to a specific (meth)acrylate derivative, polymerizing the monomers, copolymerizing AN to the polymer and adding an antioxidant to the obtained block copolymer.
CONSTITUTION: A mixture of (A) 50-95wt.% of a monomer of the formula (R1 is H or methyl; R2 is a 1-20C alkyl; (n) is integer of 5-50) and (B) 50-5wt.% of a monomer containing sulfonic acid group is subjected to the 1st stage polymerization in the presence of a polyperoxide polymerization initiator using water as a polymerization medium. Monomers composed mainly of AN are added to the obtained essentially homogeneous aqueous solution and subjected to the 2nd stage polymerization to obtain an AN-based block copolymer containing 5-50wt.% of the monomer component A. A spinning dope produced by adding 0.01-5 pts.-wt. of an antioxidant (thioether, phosphite or phenolic antioxidant) to 100 pts.wt. of the AN-based block copolymer is spun by wet, dry or dry-wet spinning process.
NISHIDA KOJI
KAWACHI HIROYUKI
DAN HIDETO
