KR20140132074A - Method of manufacturing copolymerized aramid fiber - Google Patents

Abstract

The present invention relates to a manufacturing method of a copolymerized aramid fiber. In a process of manufacturing the copolymerized aramid fiber by adding terephthaloyl dichloride to an organic solvent in which an inorganic salt and a diamine component are dissolved and making the terephthaloyl dichloride react with the inorganic salt and the diamine component to obtain a polymerized solution including a copolymerized aramid polymer, followed by spinning the polymerized solution and coagulating the polymerized solution which has been extruded, the manufacturing method of the copolymerized aramid fiber is characterized by adding the inorganic salt to the polymerized solution including the copolymerized aramid polymer in a content of 0.01-10 wt% with respect to the weight of the polymerized solution, followed by performing a spinning process and a coagulation process. The present invention allows the intrinsic viscosity of the polymerized solution to be properly increased by adding the inorganic salt to the polymerized solution in a content of 0.01-10 wt% before spinning the polymerized solution, thereby effectively preventing the diffusion of a spinning dope on the surface directly under a spinneret in the spinning process. Accordingly, spinning ability is improved and the strength of the manufactured fiber is enhanced.

Description

TECHNICAL FIELD The present invention relates to a method of manufacturing a copolymerized aramid fiber,

More particularly, the present invention relates to a method for producing a copolymerized aramid fiber by appropriately increasing the intrinsic viscosity of the polymerized solution when spinning a polymerized solution containing a copolymerized aramid polymer into a spinneret without using sulfuric acid, The present invention relates to a method for producing a copolymerized aramid fiber capable of effectively preventing spreading of a radial dope and improving radioactivity while improving fiber strength.

Aromatic polyamides, commonly referred to as aramids, include para-aramids having a structure in which benzene rings are linearly connected through an amide group (CONH), and meta-based aramids that are not.

Para-aramid has excellent properties such as high strength, high elasticity and low shrinkage. The thin thread of 5 mm thickness produced from this has a strength enough to lift a 2-tonne automobile, so it is used not only for bulletproof but also for various applications in the aerospace industry.

In addition, since aramid is carbonized black at a temperature of 500 ° C or higher, it is also in the spotlight where high heat resistance is required.

A method of producing an aramid fiber is well described in Korean Patent Registration No. 10-0910537 of the present applicant. According to this patent, an aromatic diamine is dissolved in a polymerization solvent to prepare a mixed solution, and an aromatic diacid is added to this to prepare an aramid polymer. The aramid fiber is finally completed by dissolving the aramid polymer in a sulfuric acid solvent to prepare a spinning dope, spinning the spinning dope, followed by coagulation, washing, and drying.

However, when the aramid fiber is produced through such a process, since a solid state aramid polymer is prepared and then dissolved again in a sulfuric acid solvent to prepare a spinning dope, the spinning process is complicated and harmful to the human body, And the durability is degraded due to corrosion.

Furthermore, since the sulfuric acid solvent used to dissolve the aramid polymer having high chemical resistance and removed after the spinning causes environmental pollution, it has to be appropriately treated after use. The cost for treating such spent sulfuric acid is not only economical .

In order to solve the above problem, Korean Patent No. 10-171994 discloses a method for producing an aramid fiber without using a sulfuric acid solvent by directly irradiating a copolymerized aramid polymerization solution with an emissivity pro- cess, .

Specifically, in the above prior art, terephthaloyl dichloride is added to an organic solvent in which paraphenylenediamine and cyano-para-phenylenediamine are dissolved and reacted to polymerize the polymerization solution containing the copolymerized aramid polymer, The solution was spun and coagulated to produce copolymerized aramid fibers.

However, although the above-mentioned prior art has an advantage of not using a sulfuric acid solvent, since the intrinsic viscosity of the polymerization solution used as a radiant agent is too low, spreading of the radial dope occurs on the surface immediately under the nasal decay, And the like.

Disclosure of the Invention Problems to be Solved by the Invention It is an object of the present invention to appropriately improve intrinsic viscosity of a polymerized solvent when a copolymerized aramid polymerization solvent is used as it is without any use of sulfuric acid to produce a copolymerized aramid fiber to prevent spreading of the radial dope , And to provide a method for producing a copolymerized aramid fiber which improves radioactivity and improves fiber strength.

In order to accomplish the above object, the present invention provides a process for preparing a polymerized solution by polymerizing a polymerization solution containing a copolymerized aramid polymer by adding terephthaloyl dichloride to an organic solvent in which an inorganic salt and a diamine component are dissolved, When coagulated aramid fibers are produced by solidification, 0.01 to 10% by weight of an inorganic salt is further added to the polymerization solution containing the copolymerized aramid polymer, and the resultant solution is then spun and coagulated.

Since the intrinsic viscosity of the polymerization solution is appropriately increased by adding 0.01 to 10% by weight of an inorganic salt to the polymerization solution before spinning the polymerization solution, the spinning dope spreading phenomenon can be effectively prevented , Which improves radioactivity and improves the strength of the fabricated fibers.

Hereinafter, the present invention will be described in detail.

It will be apparent to those skilled in the art that various modifications and variations can be made in the present invention without departing from the spirit or scope of the invention. It will be apparent to those skilled in the art that variations are possible. Therefore, the present invention encompasses all changes and modifications that come within the scope of the invention as defined in the appended claims and equivalents thereof.

In the present invention, first, an inorganic salt and a diamine component are added to an organic solvent and dissolved.

At this time, paraphenylenediamine and cyano-para-phenylenediamine may be dissolved in a molar ratio of 1: 9 to 9: 1 as a diamine component, or cyano-para-phenylenediamine may be solely dissolved.

Next, terephthaloyl dichloride is added to the organic solvent in which paraphenylenediamine and cyano-para-phenylenediamine are added and dissolved in the same molar amount as the diamine component, A polymerization solvent containing an aramid polymer is prepared.

Next, an inorganic salt is added to the polymerization solvent in an amount of 0.01 to 10% by weight based on the weight of the polymerization solution to improve the intrinsic viscosity of the polymerization solution to an appropriate level, preferably 50 to 1,500 poise.

Examples of the inorganic salt include calcium chloride, sodium chloride, potassium chloride, lithium chloride, magnesium chloride, and mixtures thereof.

When the addition amount of the inorganic salt is less than 0.01 wt%, the intrinsic viscosity of the polymerization solution is lowered to less than 50 poise, and the polymerization solution, that is, the spreading of the radiation dope is generated on the surface immediately under the spinneret, and the radioactivity is lowered.

On the other hand, when the addition amount of the inorganic salt is more than 10% by weight, the inorganic salt in the solution is saturated and does not dissolve and the intrinsic viscosity of the polymerization solution exceeds 1,500 poises, that is, the intrinsic viscosity is too high, swelling phenomenon occurs and radioactivity decreases.

Next, the polymerized solution prepared as described above is extruded through a spinneret using the spinning process as it is, and then the extruded polymer solution is solidified as a coagulating solution to produce copolymerized aramid fibers on the filament.

The co-aramid fibers produced by the method according to the present invention have excellent strength of 28 to 35 g / d.

Hereinafter, the present invention will be described in more detail with reference to examples and comparative examples.

Example  One

An N-methyl-2-pyrrolidone (NMP) organic solvent containing 3% by weight of CaCl ₂ was placed in a reactor under a nitrogen atmosphere, and 50 mol% of para-phenylenediamine and 40% 50 mol% of cyano-p-phenylenediamine was dissolved in the reactor to prepare a mixed solution.

Then, 100 mol% of terephthaloyl dichloride was added to the reactor containing the mixed solution, and CaO (neutralizing agent) was added at the same molar ratio as HCl generated during the polymerization, and then 1 wt% (relative to the weight of the polymerization solution) Calcium chloride was further added to prepare a polymerization solution containing the copolymerized aramid polymer.

Subsequently, the polymer solution was extruded through a spinneret, and then passed through an air gap and a coagulating liquid sequentially to form a multifilament having a linear density of 3,000 denier. The pressure in the spinning pack was 2,800 psi and the spinning speed was 600 mpm (meter per minuite).

Subsequently, the multifilament was washed with water, and the washed multifilament was dried and stretched by a drying roller set at a temperature of 150 ° C. The drawn multifilament was heat-treated at 250 ° C and wound up to produce a copolymerized aramid fiber.

Table 1 shows the results of evaluating the strength and radioactivity of the copolymerized aramid fibers.

Example  2

An N-methyl-2-pyrrolidone (NMP) organic solvent containing 3% by weight of CaCl ₂ was placed in a reactor under a nitrogen atmosphere, and 50 mol% of para-phenylenediamine and 40% 50 mol% of cyano-p-phenylenediamine was dissolved in the reactor to prepare a mixed solution.

Then, 100 mol% of terephthaloyl dichloride was added to the reactor containing the mixed solution, and CaO (neutralizing agent) was added at the same molar ratio as that of HCl generated during the polymerization while continuously adding 3 wt% (based on the weight of the polymerization solution) Sodium chloride was further added to prepare a polymerization solution containing the copolymerized aramid polymer.

Subsequently, the polymer solution was extruded through a spinneret, and then passed through an air gap and a coagulating liquid sequentially to form a multifilament having a linear density of 3,000 denier. The pressure in the spinning pack was 2,800 psi and the spinning speed was 600 mpm (meter per minuite).

Subsequently, the multifilament was washed with water, and the washed multifilament was dried and stretched by a drying roller set at a temperature of 150 ° C. The drawn multifilament was heat-treated at 250 ° C and wound up to produce a copolymerized aramid fiber.

Table 1 shows the results of evaluating the strength and radioactivity of the copolymerized aramid fibers.

Example  3

An N-methyl-2-pyrrolidone (NMP) organic solvent containing 3% by weight of CaCl ₂ was placed in a reactor under a nitrogen atmosphere, and 50 mol% of para-phenylenediamine and 40% 50 mol% of cyano-p-phenylenediamine was dissolved in the reactor to prepare a mixed solution.

Subsequently, 100 mol% of terephthaloyl dichloride was added to the reactor containing the mixed solution, and CaO (neutralizing agent) was added at the same molar ratio as HCl generated during the polymerization, and then 6 wt% (relative to the weight of the polymerization solution) Magnesium chloride was further added to prepare a polymerization solution containing the copolymerized aramid polymer.

Subsequently, the polymer solution was extruded through a spinneret, and then passed through an air gap and a coagulating liquid sequentially to form a multifilament having a linear density of 3,000 denier. The pressure in the spinning pack was 2,800 psi and the spinning speed was 600 mpm (meter per minuite).

Subsequently, the multifilament was washed with water, and the washed multifilament was dried and stretched by a drying roller set at a temperature of 150 ° C. The drawn multifilament was heat-treated at 250 ° C and wound up to produce a copolymerized aramid fiber.

Table 1 shows the results of evaluating the strength and radioactivity of the copolymerized aramid fibers.

Example  4

An N-methyl-2-pyrrolidone (NMP) organic solvent containing 3% by weight of CaCl ₂ was placed in a reactor under a nitrogen atmosphere, and 100 mol% of cyano-p-phenylenediamine The mixture was put into the reactor and dissolved to prepare a mixed solution.

Then, 100 mol% of terephthaloyl dichloride was added to the reactor containing the mixed solution, and CaO (neutralizing agent) was added at the same molar ratio as HCl generated during the polymerization, and then 1 wt% (relative to the weight of the polymerization solution) Calcium chloride was further added to prepare a polymerization solution containing the copolymerized aramid polymer.

Subsequently, the polymer solution was extruded through a spinneret, and then passed through an air gap and a coagulating liquid sequentially to form a multifilament having a linear density of 3,000 denier. The pressure in the spinning pack was 2,800 psi and the spinning speed was 600 mpm (meter per minuite).

Subsequently, the multifilament was washed with water, and the washed multifilament was dried and stretched by a drying roller set at a temperature of 150 ° C. The drawn multifilament was heat-treated at 250 ° C and wound up to produce a copolymerized aramid fiber.

Table 1 shows the results of evaluating the strength and radioactivity of the copolymerized aramid fibers.

Comparative Example  One

An N-methyl-2-pyrrolidone (NMP) organic solvent containing 3% by weight of CaCl ₂ was placed in a reactor under a nitrogen atmosphere, and 50 mol% of para-phenylenediamine and 40% 50 mol% of cyano-p-phenylenediamine was dissolved in the reactor to prepare a mixed solution.

Then, 100 mol% of terephthaloyl dichloride was added to the reactor containing the mixed solution, and a polymerization solution containing the copolymerized aramid polymer was prepared by adding CaO (neutralizing agent) at the same molar ratio as HCl generated during the polymerization.

At this time, no additional inorganic salt was added to the polymerization solution.

Subsequently, the polymer solution was extruded through a spinneret, and then passed through an air gap and a coagulating liquid sequentially to form a multifilament having a linear density of 3,000 denier. The pressure in the spinning pack was 2,800 psi and the spinning speed was 600 mpm (meter per minuite).

Subsequently, the multifilament was washed with water, and the washed multifilament was dried and stretched by a drying roller set at a temperature of 150 ° C. The drawn multifilament was heat-treated at 250 ° C and wound up to produce a copolymerized aramid fiber.

Table 1 shows the results of evaluating the strength and radioactivity of the copolymerized aramid fibers.

Comparative Example  2

An N-methyl-2-pyrrolidone (NMP) organic solvent containing 3% by weight of CaCl ₂ was placed in a reactor under a nitrogen atmosphere, and 50 mol% of para-phenylenediamine and 40% 50 mol% of cyano-p-phenylenediamine was dissolved in the reactor to prepare a mixed solution.

Subsequently, 100 mol% of terephthaloyl dichloride was added to the reactor containing the mixed solution, and CaO (neutralizing agent) was added at the same molar ratio as HCl generated during the polymerization, and then 15 wt% (relative to the weight of the polymerization solution) Sodium chloride was added to prepare a polymerization solution containing the copolymerized aramid polymer.

Subsequently, the polymer solution was extruded through a spinneret, and then passed through an air gap and a coagulating liquid sequentially to form a multifilament having a linear density of 3,000 denier. The pressure in the spinning pack was 2,800 psi and the spinning speed was 600 mpm (meter per minuite).

Subsequently, the multifilament was washed with water, and the washed multifilament was dried and stretched by a drying roller set at a temperature of 150 ° C. The drawn multifilament was heat-treated at 250 ° C and wound up to produce a copolymerized aramid fiber.

Table 1 shows the results of evaluating the strength and radioactivity of the copolymerized aramid fibers.

division burglar Radioactive Example 1 30 Great Example 2 31 Great Example 3 32 Great Example 4 30 Great Comparative Example 1 27 Bad Comparative Example 2 30 Bad

The strength and radioactivity of the above Table 1 were evaluated in the following manner.

Aramid  Strength of fiber

The strength of the aramid fiber was determined by measuring the strength at the breaking point after stretching until a sample of 25 cm in length was broken in an Instron tester (Instron Engineering Corp, Canton, Mass) according to ASTM D885, Was tested five or more times and then the average value was obtained. At this time, the tensile speed was 300 mm / min, and the initial load was 1 × 30 g of fineness.

Radioactive

It was judged to be defective when a drop phenomenon occurs in which the radiation doping drops directly into the liquid state under the spinneret due to the dew welling phenomenon immediately under the spinneret, and when the drop phenomenon occurs, it is judged to be defective.

Claims (6)

The present invention relates to a method for producing a copolymerized aramid fiber by polymerizing a polymerization solution containing a copolymerized aramid polymer by adding terephthaloyl dichloride to an organic solvent in which an inorganic salt and a diamine component are dissolved and then reacting and coagulating the polymerized solution,
Wherein the inorganic salt is added to the polymerization solution containing the copolymerized aramid polymer in an amount of 0.01 to 10% by weight based on the weight of the polymerization solution, followed by spinning and solidifying the copolymerized aramid fiber. The method according to claim 1, wherein an intrinsic viscosity of the polymerization solution is adjusted to 50 to 1,500 poise by adding an inorganic salt of the polymerization solution. The method for producing a co-aramid fiber according to claim 1, wherein the inorganic salt is at least one selected from calcium chloride, sodium chloride, potassium chloride, lithium chloride and magnesium chloride. The process for producing a co-aramid fiber according to claim 1, wherein the organic solvent is dissolved in a molar ratio of 1: 9 to 9: 1 of paraphenylenediamine and cyano-para-phenylenediamine as a diamine component.
The method for producing a co-aramid fiber according to claim 1, wherein cyano-para-phenylenediamine is solely dissolved in the organic solvent as a diamine component. The method for producing a co-aramid fiber according to claim 1, wherein terephthaloyl dichloride is added to the organic solvent in which the diamine component is dissolved in the same molar amount as the total amount of the diamine component dissolved in the organic solvent.