Method and device for preparing modified meta-aramid fiber through continuous polymerization-dry-wet spinning

Abstract

The invention discloses a method and a device for preparing modified meta-aramid fiber through continuous polymerization-dry-wet spinning. The method comprises the following steps that (1), a DMAc mixed solution of m-phenylenediamine and a copolymerized diamine monomer is prepared by using a cosolvent; (2), the isophthaloyl dichloride melt is mixed with a DMAc mixed solution of m-phenylenediamine and a copolymerized diamine monomer, and pre-polycondensation and polycondensation are carried out to obtain a modified meta-aramid resin solution; and (3), auxiliaries are added into the modified meta-aramid resin solution, filtering, defoaming, and spinning are carried out by a dry-wet method to obtain modified meta-aramid fibers. A pre-polymerization system of the continuous polymerization-dry-wet spinning device comprises a micro-mixer and a micro-reactor which are connected in sequence, and a micro-channel of the micro-reactor is designed to be heart-shaped; and the polycondensation system is a multi-stage microscrew combination. The problems in the preparation process of the meta-position aramid fiber are comprehensively solved, the obtained product is complete in structure, excellent in performance, stable and controllable, and continuous and efficient production can be achieved.

Description

technical field [0001] The invention belongs to the field of macromolecular materials, and relates to resin and fiber manufacturing technology, in particular to a method and device for preparing aramid fiber products by continuous polymerization-dry-wet spinning technology. Background technique [0002] The unique chemical structure of polyaramid endows it with excellent properties such as high modulus, high strength, high temperature resistance, and insulation. Since its appearance in the 1960s and 1970s, it has attracted a large number of domestic and foreign scientific researchers to carry out research and development. It has become a high-tech One of the key materials in the field, it is widely used in cutting-edge fields such as electronics, national defense, aerospace, military and emergency rescue, as well as high-end civilian fields such as rail transportation, construction, high-temperature transmission, filtration, and sporting goods. Heterocycles such as imidazole...

AI Technical Summary

Problems solved by technology

On the one hand, due to the rapid heat release of the meta-aramid polymerization system, and the kettle reactor only has an external jacket for heat exchange, the heat of the reaction system cannot be removed quickly, and the low temperature of the reaction system and the temperature uniformity of the overall reaction system cannot be guaranteed. , so that the reaction synchronization is very poor, there are many side reactions, and it is difficult to control the molecular weight and distribution of the polymer; It is because the viscosity of the polymerization system increases in the later stage of the reaction, and the difficulty of mixing materials is further increased, resulting in local monomer concentration being too high or too low, resulting in local detonation or local polymerization too low, insufficient reaction, resulting in the obtained meta-aramid resin Low molecular weight, molecular weight distribution, poor spinnability of resin solution

[0006] 2) The properties of fibers obtained by wet spinning cannot meet the application requirements of high-end fields

[0008] 3) Continuous high-efficiency production has not been realized; problems such as the neutralization of the meta-aramid resin solution, low filtration efficiency, and the clogging of the spinneret caused by the inorganic salts contained therein, the phenomenon of wool and broken filaments, and the unsatisfactory properties of the obtained fibers, etc.

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