A method of obtaining a hydrophilic polyacrylonitrile fiber

 

(57) Abstract:

The invention relates to the field of finishing and modification of fibrous textile materials in the form of fibers, yarns, fabrics or knitted fabrics and can be used for manufacture of products for sanitary and technical purposes with high moisture absorption. Describes how to obtain hydrophilic polyacrylonitrile fiber by saponification of the original fiber sodium hydroxide solution, wherein the saponified fibers are first treated with 3-7% aqueous solution of calcium chloride within 10-20 min, and then impregnated with a 1-5% aqueous solution of sodium alginate. The technical result is the obtaining of acrylic fiber with high moisture absorption. table 1.

The invention relates to the field of finishing and modification of fibrous textile materials in the form of fibers, yarns, fabrics or knitted fabrics and can be used for manufacture of products for sanitary and technical purposes with high moisture absorption.

A method of obtaining hydrophilic polyacrylonitrile fiber-based copolymer of Acrylonitrile and methyl methacrylate. High g is. N 6. - S. 8). The disadvantages of this method include the use of non-conventional ternary copolymer, and double, as well as the difficulty of making a precipitation bath.

The closest technical solution is the method of processing polyacrylonitrile fibers with sodium hydroxide. The treatment is carried out with 2.5% NaOH solution at a temperature of 95-98oC for 7-8 minutes the Disadvantage of this method is the relatively low moisture absorption (wolf L. A. and other Textile materials with antimicrobial properties. E. I. Textile industry. Domestic production method. - 1985. - N 3. - S. 7-13).

The technical result is the obtaining of acrylic fiber with high moisture absorption.

The technical result is achieved by the fact that ordinary commodity polyacrylonitrile fiber (ternary copolymer) successively treated with sodium hydroxide solution of a concentration of 3-5% at a temperature of 96-98oC, calcium chloride 3-7% at temperature (20 2)oC and sodium alginate 1-5% at temperature (20 2)oC.

Treatment with solutions of calcium chloride and sodium alginate can be performed immediately after saponification of acrylic fiber, the single difference of the claimed method is the sequential processing of aqueous solutions of sodium hydroxide, calcium chloride and sodium alginate, which allows to obtain a fiber with high moisture absorption.

In the proposed method sequential processing of aqueous solutions of sodium hydroxide, calcium chloride and sodium alginate leads to unexpected effect of obtaining fibers with high moisture absorption up to 1580%.

It is known that the proposed connections are used in various industries and medicine. Calcium chloride (CaCl2) - upon receipt of calcium, for drying of gases and liquids, its solutions are used as a medicinal remedy for allergies and bleeding. Sodium alginate C5H4O2[(OH)2COONa] is a linear copolymer sodium salt D-mouronval and 2-guluronic acids associated 1,4--glucoside links - used in food, pharmaceutical and textile industries, in the manufacture of paper.

The use of serial treatment of PAN fibers with aqueous solutions of sodium hydroxide, calcium chloride and sodium alginate to obtain fibers with high moisture absorption in the prior art by the authors was not found.

The proposed method for processing PAN fiber is implemented as education is IDA sodium concentration of 3-5% at a temperature of 96-98oC (boiling water bath) for 15-25 minutes Then colout (0,0050,001 m solution of H2SO4) and washed with demineralized water. The processing solution of calcium chloride is carried out at a temperature of (202)oC for 10-20 min, the concentration of CaCl2- 3-7%, the volume of solution 250 ml calcium maintenanced POLYACRYLONITRILE fiber impregnated at a temperature of (202)oC solution of sodium alginate concentration of 1-5% and press management (pressed 150-200%) and dried.

Similar technologies can be treated yarn, fabric or knitted fabric. Examples of specific performance and properties of the fibers treated by the proposed method are presented in the table.

Table data - mapping POS. 15 (prototype) POS.2-5, 7-10, 12 (proposed method) to confirm the achievement of the technical result, i.e., in comparison with the prototype is a significant increase in moisture absorption upon contact with water: more than 2 times for 10 min (POS. 15 - 362% and POS. 2 - 758%) and more than 4 times for 60 min (POS. 15 -375% and POS.2 - 1580%). Normal (nesomyinae) POLYACRYLONITRILE fiber, treated with a solution of sodium alginate in the proposed conditions, has a moisture absorption 158% (10 min) and 205% (60 min) (Ref. 14), saponified POLYACRYLONITRILE fiber with sodium alginate has vlagopoulos the maximum moisture absorption at a concentration of calcium chloride 3% (Ref. 1): 570% at 10 min and 450% at 60 minutes

Fiber, processed by the proposed method is promising when creating dressings, manufacture various sanitary and technical water-absorbing means.

A method of obtaining a hydrophilic polyacrylonitrile fiber by saponification of the original fiber sodium hydroxide solution, wherein the saponified fibers are first treated with 3 - 7% aqueous solution of calcium chloride for 10 to 20 min, and then impregnated with 1 - 5% aqueous solution of sodium alginate.

 

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