Para-aramid dope of low degree of polymerization, para-aramid fiber and para-aramid pulp prepared therefrom and their preparation method

摘要

Low-polymerization para exhibiting optical anisotropy, containing 4-10% by weight of para-aramid and 2-10% by weight of alkali metal halide or alkaline earth metal halide in polar amide solvent with intrinsic viscosity of 1.0-2.5 dl / g -Aramid, para-aramid fibers obtained by spinning the first low degree of polymerization of para-aramid dope, and the second para-aramid fibers are made into short fibers, and microfibers are formed into microfibers as mechanical high shear force, 0.94-0.99 moles of para-oriented aromatic dicarboxyl to 1 mole of para-oriented aromatic diamine in a para-aramid pulp obtained by drying the fiber, a polar amide solution in which 2-10 weight alkali metal chloride or alkyl earth metal chloride is dissolved. An acid halide was added, and a polymerization reaction was carried out at a temperature of -20 to 50 占 폚 to give para- A method for producing para-aramid fibers, comprising 100 moles of para-oriented aromatic diamine, which forms an optically anisotropic para-aramid dope having a low degree of polymerization having a amide concentration of 4 to 10% by weight, and emits the dope. 0.95-0.98 mole of para-oriented aromatic dicarboxylic acid halide is added, and the said 4th or 5th para-aramid fiber is cut | disconnected, and it cuts into short fibers. And a method for producing para-aramid pulp characterized by drying microfibers obtained by microfiberization as mechanical high shear force.