A method for environmentally friendly production of meta-aramid precipitated fibers

Abstract

The invention relates to the technical field of special synthetic fiber manufacture, in particular to a method for environment-friendly production of meta-position aramid fiber fibrid. The method comprises the following steps that 1, a meta-position aramid fiber resin solution is prepared; 2, meta-position aramid fiber resin is neutralized; 3, the meta-position aramid fiber resin is subjected to fiber precipitation; 4, a precipitation fiber product is separated and washed; 5, a solvent DMC and lithium chloride are recovered. The method adopts the lithium hydroxide to serve as a neutralizer of a polymerization resin solution, and calcium hydroxide low in price and non-environment-friendly in operating interface and a neutralizing product calcium chloride high in environment-friendly disposal cost are not adopted. Customized production of physical and chemical indicators of a product can be achieved through selective control of process parameters in the fiber precipitation process. A newly increased solvent preparation kettle is optimized through a process, and the production capacity of the polymerization reaction kettle is improved for more than one time. The reaction kettle and a solvent recovery device of an existing aramid fiber production line can be concurrently used for producing the meta-position aramid fiber fibrid, and the investment cost can be remarkably reduced.

Description

technical field [0001] The invention relates to the technical field of manufacturing special synthetic fibers, in particular to an environment-friendly method for producing meta-aramid fibrids. Background technique [0002] The precipitated fiber of meta-aramid 1313 is a high-temperature-resistant special fiber with excellent comprehensive properties. It has excellent thermal stability, flame retardancy, electrical insulation, chemical stability, and radiation resistance. It is used in the manufacture of electrical insulation Paper, high-temperature filter materials, honeycomb structure materials, etc. have a wide range of uses. [0003] Comparing the production process of aramid spinning fiber, the precipitating fiber is sent to the precipitating equipment after diluting the polymer resin solution and the precipitating solvent (coagulation liquid), and is coagulated by shearing to form ultra-short fibers, and then separated by the solvent. , The product is obtained after t...

AI Technical Summary

Problems solved by technology

[0005] In the link of resin precipitating and forming fibers, with the expansion of the application range of precipitating fiber products as processing raw materials and downstream products, the quality indicators of precipitating fiber products (including: size distribution, specific surface area, beating degree, shape, molecular weight distribution and Crystallinity, etc.) have put forward higher quality requirements or customized production requirements for indicators, and the existing technical indicators and precipitation equipment performance have been difficult to meet market demand;

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