Polyacrylonitrile dry powder suitable for dry acrylic fiber spinning, and preparation method thereof

Abstract

The invention relates to a polyacrylonitrile dry powder and a preparation method thereof, and especially relates to a polyacrylonitrile dry powder suitable for dry acrylic fiber spinning. The polyacrylonitrile dry powder is prepared through a polymerization reaction of acrylonitrile, methyl acrylate, sodium styrenesulfonate and 2-acrylamido-2-methylpropanesulfonic acid used as copolymerization monomers. The polyacrylonitrile dry powder prepared in the invention has the advantages of low water content, moderate molecular weight and molecular weight distribution, good granularity and good internal porosity amount of particles, so a spinning stock solution prepared in the dry spinning process has the advantages of good elasticity, few bubbles, bright color, smooth spinning process, and obtaining of a spinning product with good chromaticity and strong hygroscopicity. The invention also provides a preparation method of the polyacrylonitrile dry powder suitable for dry acrylic fiber spinning. The method comprises the following steps: adding the copolymerization monomers into a polymerization kettle, adding an assistant, and carrying out a polymerization reaction; and adding EDTA to end the reaction, filtering a material obtained after the polymerization reaction, washing, drying to obtain polyacrylonitrile resin, and crushing to form fine powder in order to obtain the polyacrylonitrile dry powder suitable for dry acrylic fiber spinning.

Description

technical field [0001] The invention relates to a polyacrylonitrile dry powder and a preparation method, in particular to a polyacrylonitrile dry powder suitable for dry acrylic fiber spinning and a preparation method. Background technique [0002] The polyacrylonitrile dry spinning process is to dissolve the polyacrylonitrile dry powder obtained after polymerization in the organic solvent dimethylformamide (DMF) or dimethylacetamide (DMAC) to form a spinning stock solution, and then spin After the silk stock solution is transported to the spinning tunnel, the solvent is removed by means of hot nitrogen. The dry spinning forming process is relaxed, and the internal structure of the fiber is uniform, so that the physical and mechanical properties and dyeing performance of the dry spinning fiber are better, and the spinning section strength is good. In addition, the dry spinning speed is high, the number of spinneret holes is small, the solvent recovery is simple, the spinning...

AI Technical Summary

Problems solved by technology

In addition, the dry spinning speed is high, the number of spinneret holes is small, the solvent recovery is simple, the spinning process is simple, and the floor space is small; the unique dog-bone structure of the dry spinning fiber makes its characteristics close to natural wool. The fabric has good elasticity, light weight, and the finished product has the characteristics of warmth, comfort, and elegant luster; but dry spinning is prone to occur during the preparation of spinning stock solution (1) The spinning stock solution has poor viscoelasticity, resulting in spinning When the stock solution is released, the flow rate is fast, and the adapter has no outlet expansion phenomenon; (2) When the water content in the spinning stock solution exceeds the standard, the air bubbles in the spinning stock solution will increase, resulting in problems such as parallel filaments and broken filaments during spinning. Smooth spinning; (3) Problems such as poor color of the spinning stock solution affect the final quality of the product

Since these problems will lead to unsmooth spinning, which will affect the quality of the final product, and will also cause problems such as increased production intensity of workers during production, it is necessary to strictly control the copolymerization process conditions of acrylonitrile in the early stage, such as copolymerization Types of the second, third and fourth monomers in the polymerization and the ratio of each monomer, polymerization temperature and system acidity, moisture content of the dry polymer powder after drying, particle size of the dry powder and internal pores of the particles, molecular weight and molecular weight distribution Etc., to obtain polyacrylonitrile dry powder suitable for dry spinning, so as to provide strong support for the subsequent preparation of qualified spinning stock solution, in order to facilitate the smooth operation of production and stable product quality, and to obtain spinning products with excellent performance

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