Method for preparing anti-pilling acrylic fibers from acrylonitrile and vinyl acetate

Abstract

The invention relates to a method for preparing anti-pilling acrylic fibers from acrylonitrile and vinyl acetate, which comprises the following steps: (1) dissolving a polyacrylonitrile polymer in a 40-60% sodium thiocyanate water solution through a dissolver, wherein in the polyacrylonitrile polymer, the acrylonitrile content is 85-95%, the vinyl acetate content is 5-10%, the sodium methylallyl sulfonate content is less than 1%, and the viscosity-average molecular weight of polyacrylonitrile is 45-65 thousand; (2) after debubbling and filtering a spinning solution, metering through a spinning metering pump, and extruding through spinneret orifices; (3) extruding into a coagulation bath through a spinneret plate to form nascent fibers; (4) sending the fibers into a secondary coagulation bath to form, and carrying out cold drawing, water washing and hot drawing, wherein the total drawing magnification is less than or equal to 12; (5) carrying out hot drying and compaction treatment on the fibers; and (6) thermoforming the fibers. The acrylic fibers prepared by the method have the advantages of high fracture resistance and high pilling resistance.

Description

technical field [0001] The invention relates to a production method of wet anti-pilling acrylic fiber, in particular to a method for preparing anti-pilling acrylic fiber by utilizing acrylonitrile and vinyl acetate. Background technique [0002] Most synthetic fibers suffer from the phenomenon of "pilling" during use. Because the strength of acrylic fiber is higher than that of natural fibers, the formation rate of fiber pellets on the surface of the product is greater than the rate of shedding, so when the friction force cannot eliminate the fiber pellets, the formed fiber pellets will remain on the surface of the fabric for a long time , thereby affecting the appearance and wearing comfort of the fabric. There are also many domestic and foreign patent documents about the development of anti-pilling fibers, such as <publication number> 1948567 in the anti-pilling acrylic fiber production method involving the blending of polyacrylonitrile polymers that adopt two diffe...

AI Technical Summary

Problems solved by technology

And the anti-pilling effect of the fabric is not obviously improved after repeated washing

In addition, in the production of anti-pilling acrylic fiber described in US Patent , the concentration of sodium thiocyanate in the coagulation bath is controlled to be 50%-70% of that in the spinning solution, and this concentration range is too slow for solvent diffusion in spinning forming , fiber formation is too slow to cause normal spinning

U.S. Patent describes the production of anti-pilling fibers by the second drafting method, but due to the high spinning speed, it is difficult to design such re-drawing equipment, and the operation is inconvenient and the cost is high

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