| abstract |
High modulus shaped articles such as fibers and films, composed of a wholly aromatic copolyamide, are provided. The wholly aromatic copolyamide is comprised of recurring units of the formulae:n andn wherein Ar l , Ar 2 and Ar 3 independently stand for divalent groups selected fromn n andn in which X's independently stand for a group selected from halogeno, alkyl, aralkyl, aromatic, alkoxy, acetyl and cyano, n is 1 to 3 and Y is selected fromn in which R' stands for an 1-5C alkyl group, and the copolymerization ratio expressed by the molar ratio of the total of Ar,, Ar 2 and Ar 3 falls within the square hatched region in a triangular coordinate of Figure 1, and said copolyamide has an intrinsic viscosity of at least 1.5. The shaped articles are prepared by a process wherein a solution comprised of the above-defined wholly aromatic copolyamide, a halide of a metal of Group I or II of the Periodic Table and an amide type organic solvent is subjected to wet or dry shaping; and then, the shaped article is stretched at a stretch ratio of at least 1.5 at an elevated temperature. |