CN101240468A - A kind of polyacrylonitrile-chitin composite fiber and its manufacturing method - Google Patents

Abstract

The invention relates to a polyacrylonitrile-chitin composite fiber and a manufacturing method thereof. The composite fiber is composed of chitin and polyacrylonitrile, the chitin accounts for 1-20% of the solid content of the composite fiber, and the polyacrylonitrile accounts for 80% to 99% of that; its manufacturing method includes: 1) dissolving polyacrylonitrile in a solvent to form a polyacrylonitrile solution with a content of 3% to 45%; 2) adding chitin to the polyacrylonitrile solution, The addition amount is 1 to 20% of the dry weight of polyacrylonitrile, and it is made into polyacrylonitrile-chitin spinning solution, which is left to defoam; Stretching, washing, drying and other conventional processes to make finished products. The invention can improve the human affinity of the polyacrylonitrile fiber, endow the fiber with the special effect of antibacterial and antipruritic, and increase the antistatic property of the polyacrylonitrile fiber.

Description

A kind of polyacrylonitrile-chitin composite fiber and its manufacturing method

technical field

The invention belongs to the field of composite materials and its manufacturing method, in particular to a polyacrylonitrile-chitin composite fiber and its manufacturing method.

Background technique

Polyacrylonitrile fiber, commonly known as acrylic fiber, is a synthetic fiber with excellent warmth retention, excellent dyeability, and no moth and mildew. After dyeing, it can obtain brighter colors than wool. Polyacrylonitrile is widely used It is used to make wool-like products, so polyacrylonitrile is also called artificial wool. However, polyacrylonitrile also has many disadvantages: poor hydrophilicity, easy to charge static electricity in dry weather, poor human affinity, and poor antibacterial performance.

In order to improve the performance of these shortcomings of polyacrylonitrile, researchers have done a lot of work on modified polyacrylonitrile, such as silk grafted polyacrylonitrile, milk protein grafted polyacrylonitrile fiber, but these must be in the polymerization stage. Great changes are made to the original equipment and processes, which cannot be widely promoted.

Chitin and its derivatives have good antibacterial properties and certain hydrophilicity. my country is rich in chitin resources. Recently, some people have also begun to use chitin and its derivatives for the modification of chemical fibers, such as the Chinese patent of "Preparation method and application of carboxymethyl chitosan and alginic acid blend film or fiber" with application number 99120092 . Among chitin and its derivatives, chitin has the lowest cost, but chitin has poor compatibility with some conventional fiber-forming polymers, especially chitin is difficult to melt and insoluble in water, dilute acid, dilute Alkali, concentrated alkali and general organic solvents, so the application in chemical fiber modification is limited.

Contents of the invention

The technical problem to be solved by the present invention is to provide a polyacrylonitrile-chitin composite fiber and its manufacturing method, so as to make up for the deficiencies and defects of the prior art and meet the needs of production and life.

The present invention utilizes chitin and polyacrylonitrile to have polar groups, and compatibility is good, and particularly chitin can be dissolved in the partial solvent of polyacrylonitrile (sodium thiocyanate, potassium thiocyanate aqueous solution), therefore makes After chitin and polyacrylonitrile are uniformly mixed and dispersed in the spinning solution, the polyacrylonitrile-chitin composite fiber is prepared by the original spinning process of polyacrylonitrile fiber to improve the hydrophilicity and resistance of polyacrylonitrile fiber. Electrostatic properties, affinity with the human body and antibacterial properties.

The polyacrylonitrile-chitin composite fiber of the invention is composed of chitin and polyacrylonitrile, the chitin accounts for 1-20% of the solid content of the composite fiber, and the polyacrylonitrile accounts for 80-99% of the fiber solid content.

The polyacrylonitrile is an acrylonitrile homopolymer or copolymer, with a conventional molecular weight of 50,000 to 170,000 or an ultrahigh molecular weight of 500,000 to 2,000,000;

The chitin is an industrial chitin product or directly extracted from the wings or shells of arthropods (spiders, crustaceans) and the cell walls of fungi and algae;

A kind of preparation method of polyacrylonitrile-chitin composite fiber of the present invention, comprises the steps:

(1) dissolving polyacrylonitrile in a solvent to make a polyacrylonitrile solution with a mass fraction of 3 to 45%;

(2) Dissolve chitin powder in a polyacrylonitrile solvent or make ultrafine powder and add it to the polyacrylonitrile solution in an amount of 1 to 20% of the dry weight of polyacrylonitrile to make polypropylene Nitrile-chitin spinning solution, standing for defoaming;

(3) The spinning solution obtained in step (2) is sprayed out through the spinneret holes, solidified and formed, and then processed into a finished product after several conventional processes such as stretching, washing, crimping, shaping, and drying.

The solvent in the step (1) is an aqueous solution of zinc chloride, sodium thiocyanate, potassium thiocyanate, nitric acid with a mass percentage of 30% to 75%, and ethylene carbonate with a mass percentage of 5% to 80%. One or more of sodium thiocyanate solution, dimethylformamide, dimethylacetamide, and dimethylsulfoxide.

The particle size range of the ultrafine powder in the step (2) is 100nm-1000nm.

The curing molding in the step (3) is completed through wet spinning, dry spinning, dry-wet spinning or gel spinning.

The wet spinning process is spinning, stretching, washing, drying or washing, stretching, and drying. Specifically, the spinning solution is sprayed from the spinneret and enters the spinning bath to solidify into silk, and the coagulation bath is a solvent. An aqueous solution with a mass concentration of 0-30% and a temperature of 0-70°C. The stretching is carried out in multiple stages, ranging from 1 to 3 stages. A hot water bath or saturated water vapor is used as the stretching medium, and the stretching temperature is 65-70°C. 140°C, the total stretching ratio is 1-10 times; drying can be carried out by radiation or contact heating, and the temperature is 80-170°C.

The dry spinning process is spinning, stretching and drying, that is, the spinning solution heated to 130-140°C is sprayed out from the special spinneret for spinning hollow fibers and then enters the spinning tunnel to solidify into filaments, and the spinning The length of the tunnel is 6-10m, the medium is air, nitrogen or saturated water vapor, heated to 280-400°C; stretching is carried out in 1-3 stages, hot water bath or saturated water vapor is used as the stretching medium, and the temperature is 65-140°C , the total stretching ratio is 1 to 10 times; drying can be carried out by radiation or contact heating, and the temperature is 80 to 170°C.

The dry-wet spinning molding process is spinning, stretching, washing, drying or spinning, washing, stretching, drying, wherein the spinning solution is first passed through an air gap after being sprayed from the spinneret, and then Enter the spinning bath and solidify into silk, the medium of the air gap is air or nitrogen, the length of the air gap is 1-10cm, the coagulation bath is an aqueous solution with a solvent mass concentration of 0-30%, and the temperature is 0-70°C; The stretching is 1-3 grades, hot water bath or saturated water vapor is used as the stretching medium, the stretching temperature is 65-140°C, and the total stretching ratio is 1-10 times; the drying is through radiation and contact heating To carry out, the temperature is 80 ~ 170 ℃.

The gel spinning process is spinning, washing, extracting, stretching, and drying. Specifically, the spinning solution heated to 130-180°C is sprayed out from the special spinneret for spinning hollow fibers and enters through the air gap. Introduce into the freezing solidification bath to freeze to form gel state filaments, the medium of the air gap is air or other gas nitrogen, the length of the air gap is 1 ~ 10cm, the coagulation bath is an aqueous solution with a solvent mass concentration of 75% ~ 85%, and the temperature is 0～10 DEG C; The described extraction is to introduce the gel state filaments coming out from the coagulation bath into a solvent with good volatility, and the solvent with good volatility has ethanol, ethylene glycol or glycerol; The above-mentioned stretching is 2 to 3 stages, using hot water bath, hot alcohol bath or saturated water vapor as the stretching medium, the stretching temperature is 65-140°C, and the total stretching ratio is 10-30 times; Drying can be carried out by radiation, contact heating or gas medium, and the temperature is 80-170°C.

Beneficial effects of the present invention:

Improve the human affinity of polyacrylonitrile fiber, in addition to endow the fiber with special antibacterial and anti-itching effect, and increase the antistatic property of polyacrylonitrile fiber.

Detailed ways

Below in conjunction with specific embodiment, further illustrate the present invention. It should be understood that these examples are only used to illustrate the present invention and are not intended to limit the scope of the present invention. In addition, it should be understood that after reading the teachings of the present invention, those skilled in the art can make various changes or modifications to the present invention, and these equivalent forms also fall within the scope defined by the appended claims of the present application.

Example 1

A polyacrylonitrile-chitin composite fiber, the composite fiber is composed of chitin and polyacrylonitrile, the chitin accounts for 1% of the solid content of the composite fiber, and the polyacrylonitrile accounts for 99% of the solid content of the fiber.

Dissolve polyacrylonitrile and chitin powder with a viscosity average molecular weight of 90000 in 51.3% sodium thiocyanate aqueous solution to make a spinning solution with a concentration of 11%. The weight ratio of polyacrylonitrile to chitin is 100:1. After stirring evenly, let it stand for 12 hours to defoam.

The spinning solution enters the spinning hole through the metering pump and is sprayed out. Enter the first coagulation bath, the content of sodium thiocyanate in the coagulation bath is 9%, and the temperature is 10 ℃. Then enter the second coagulation bath for pre-stretching. The coagulation bath is 3% sodium thiocyanate aqueous solution, and the bath temperature is 50° C. and the stretch ratio is 1.5 times. Then it is stretched with saturated water vapor, the stretching temperature is 100°C, and the stretching ratio is 10 times, then washed with water, oiled, and dried at a temperature of 100°C. The dried fiber is crimped at 80°C, then heat-set at 130°C, oiled again, and dried at 80°C to obtain a finished polyacrylonitrile/chitin composite fiber.

Example 2

A polyacrylonitrile-chitin composite fiber, the composite fiber is composed of chitin and polyacrylonitrile, the chitin accounts for 10% of the solid content of the composite fiber, and the polyacrylonitrile accounts for 90% of the solid content of the fiber.

The polyacrylonitrile that the viscosity-average molecular weight is 120000 is dissolved in the zinc chloride aqueous solution of 65% by weight, makes the spinning solution that concentration is 12%, then mixes with the chitin superfine powder of 500nm in the ratio of 9:1, After stirring evenly, let it stand for 12 hours to defoam.

The spinning solution enters the spinning hole through the metering pump and is sprayed out. Enter the first coagulation bath, the content of calcium chloride in the coagulation bath is 12%, and the temperature is 30 ℃. Then go through the second coagulation bath for pre-stretching. The coagulation bath is a 4% aqueous solution of sodium calcium chloride solution, the temperature is 50° C., and the stretching ratio is 3 times. After steam stretching, the stretching temperature is 70°C, and the stretching ratio is 5 times, then washed with water, oiled, and dried at a temperature of 110°C. The dried fiber is crimped at 70°C, heat-set at 80°C, oiled again, and dried at 90°C to obtain a finished polyacrylonitrile/chitin composite fiber.

Example 3

A polyacrylonitrile-chitin composite fiber, characterized in that: the composite fiber is composed of chitin and polyacrylonitrile, chitin accounts for 20% of the solid content of the composite fiber, and polyacrylonitrile accounts for 80% of the solid content of the fiber .

Dissolve polyacrylonitrile in dimethyl sulfoxide to prepare a spinning solution with a concentration of 25%, and then mix it with 700nm chitin ultrafine powder at a ratio of 8:2, stir evenly, and let it stand for 12 hours for degassing.

The spinning solution enters the spinning hole through the metering pump and is sprayed out. Enter the first coagulation bath, the content of dimethyl sulfoxide in the coagulation bath is 20%, and the temperature is 20°C. Pre-stretching is carried out through the second coagulation bath, the coagulation bath is 9% dimethyl sulfoxide, the temperature is 50° C., and the stretching ratio is 3 times. After steam stretching, the stretching temperature is 35°C, and the stretching ratio is 5 times, then washed with water, oiled, and dried at a temperature of 110°C. The dried fiber is crimped at 50°C, heat-set at 120°C, oiled again, and dried at 110°C to obtain a finished polyacrylonitrile/chitin composite fiber.

Claims (11)

1. A polyacrylonitrile-chitin composite fiber is characterized in that: the fiber is made up of chitin and polyacrylonitrile, and chitin accounts for 1% to 20% of the solid content of the composite fiber, and polyacrylonitrile accounts for 10% of the solid content of the fiber. 80-99%. 2. The polyacrylonitrile-chitin composite fiber according to claim 1, characterized in that: the polyacrylonitrile is an acrylonitrile homopolymer or copolymer, and the viscosity-average molecular weight is a conventional molecular weight or a viscosity-average molecular weight of 50,000 to 170,000. Ultra-high molecular weight with a molecular weight of 500,000 to 2,000,000. 3. The polyacrylonitrile-chitin composite fiber according to claim 1, characterized in that: said chitin is an industrial chitin product or directly from the wings or shells of arthropod spiders, crustaceans and Extracted from the cell walls of fungi and algae. 4. a preparation method of polyacrylonitrile-chitin composite fiber, comprising the steps of: (1) dissolving polyacrylonitrile in a solvent to make a polyacrylonitrile solution with a mass fraction of 3 to 45%; (2) Dissolve chitin powder in a polyacrylonitrile solvent or make ultrafine powder and add it to the polyacrylonitrile solution in an amount of 1 to 20% of the dry weight of polyacrylonitrile to make polypropylene Nitrile-chitin spinning solution, standing for defoaming; (3) The spinning solution obtained in step (2) is sprayed out through the spinneret holes, solidified and formed, and then processed into a finished product after several conventional processes of stretching, washing, crimping, shaping and drying. 5. the preparation method of polyacrylonitrile-chitin composite fiber according to claim 1 is characterized in that: the solvent in the described step (1) is zinc chloride, thiocyanate that mass percent is 30%～75% sodium thiocyanate, potassium thiocyanate, aqueous solution of nitric acid, ethylene carbonate sodium thiocyanate solution with a mass percentage of 5% to 80%, dimethylformamide, dimethylacetamide, and dimethyl sulfoxide one or several. 6. The preparation method of polyacrylonitrile-chitin composite fiber according to claim 1, characterized in that: the ultrafine powder particle size range in the step (2) is 100nm-1000nm. 7. the preparation method of polyacrylonitrile-chitin composite fiber according to claim 1 is characterized in that: the solidification molding in described step (3) is through wet spinning, dry spinning, dry-wet spinning Spinning or gel spinning process is completed. 8. the preparation method of polyacrylonitrile-chitin composite fiber according to claim 7 is characterized in that: described wet spinning process is spinning, stretching, washing, drying or washing, stretching, drying, Specifically, the spinning solution is sprayed from the spinneret and enters the spinning bath to solidify into filaments. The coagulation bath is an aqueous solution with a solvent mass concentration of 0-30%, and the temperature is 0-70°C. The stretching is carried out in multiple stages. For grades 1 to 3, hot water bath or saturated water vapor is used as the stretching medium, the stretching temperature is 65 to 140°C, and the total stretching ratio is 1 to 10 times; drying is carried out by radiation and contact heating, and the temperature is 80～170℃. 9. The preparation method of polyacrylonitrile-chitin composite fiber according to claim 7, characterized in that: the dry spinning process is spinning, stretching, drying, specifically heating to 130-140°C The spinning solution is sprayed from the special spinneret for spinning hollow fibers and then enters the spinning tunnel to solidify into filaments. The spinning tunnel is 6-10m long, the medium is air, nitrogen or saturated water vapor, and it is heated to 280-400°C; Stretching is carried out in 1-3 stages, hot water bath or saturated water vapor is used as the stretching medium, the temperature is 65-140°C, and the total stretching ratio is 1-10 times; drying is carried out by radiation, contact heating, and contact heating Carry out, the temperature is 80～170 ℃. 10. the preparation method of polyacrylonitrile-chitin composite fiber according to claim 7 is characterized in that: described dry-wet spinning molding process is spinning, stretching, washing, drying or spinning, Washing, stretching, and drying, wherein the spinning solution is sprayed from the spinneret and passes through an air gap, and then enters the spinning bath to solidify into filaments. The medium of the air gap is air or nitrogen, and the length of the air gap is 1~ 10cm, the coagulation bath is an aqueous solution with a solvent mass concentration of 0-30%, and the temperature is 0-70°C; the stretching level is 1-3, and the hot water bath or saturated water vapor is used as the stretching medium, and the stretching temperature is 65-70°C. 140°C, the total stretching ratio is 1-10 times; drying is carried out by radiation, contact heating, and the temperature is 80-170°C. 11. the preparation method of polyacrylonitrile-chitin composite fiber according to claim 7 is characterized in that: described gel spinning process is spinning, washing, extraction, stretching, drying, specifically heating to The spinning solution at 130-180°C is sprayed out from the special spinneret for spinning hollow fibers, and then enters into the cooling and solidifying bath through the air gap to freeze to form gel state filaments. The medium of the air gap is air or nitrogen, and the air gap The length is 1-10cm, the coagulation bath is an aqueous solution with a solvent mass concentration of 75%-85%, and the temperature is 0-10°C; the extraction is to introduce the gel-state filaments coming out of the coagulation bath into a solvent with good volatility. The solvent with good volatility includes ethanol, ethylene glycol or glycerin; the stretching is 2-3 grades, and a hot water bath, a hot alcohol bath or saturated water vapor is used as the stretching medium, and the stretching temperature is 65-140°C, the total stretching ratio is 10-30 times; drying is carried out by radiation, contact heating or gas medium, and the temperature is 80-170°C.