KR20100108976A - Aramid pulp and method for manufacturing the same - Google Patents

Abstract

PURPOSE: An aramid pulp and a manufacturing method thereof are provided to reduce aramid manufacturing costs and environmental contamination by removing waste material processing costs by recycling waste dope and waste filament. CONSTITUTION: An aramid pulp is manufactured by using a chopped fiber. The waste aramid fiber is manufactured from the aramid waste dope. The aramid pulp has the cross sectional deviation of 3-100% and freeness of 300-400ml. A waste aramid single fiber is manufactured. The waste aramid single fiber is washed. The washed waste aramid single fiber is dispersed into the water. A slurry is manufactured and the slurry is fibrillated. A spinning dope is spun by using a spinneret(10) after a spinning process. A filament is formed by solidifying it in a coagulation bath after passing through an air gap.

Description

Aramid pulp and method for manufacturing the same

The present invention relates to aramid pulp and a method for manufacturing the same, specifically, in the manufacture of aramid pulp, a large amount of waste dope and cut filaments generated during the spinning and weaving process and the yarn, fabric and nonwoven fabric discarded for a long time And the like to recycle aramid pulp.

Fibrous and nonfibrous reinforcements have been used for many years in friction products, seal products and other plastic or rubber products. Such reinforcements typically should exhibit high wear and heat resistance.

Asbestos fibers have been generally used as fibrous reinforcing materials, but have been found to be harmful to humans, and their use is prohibited. Therefore, alternatives to various asbestos fibers have been proposed, and one of the most noticed among them is aramid pulp made using aramid fibers. Aramid pulp is used as a reinforcement for various articles, for example, widely used as a reinforcement for brake pads, clutches, gaskets and the like.

Generally, wholly aromatic polyamide fibers, collectively referred to as aramid fibers, include para-aramid fibers and meta-aramid fibers having a structure in which the benzene rings are connected linearly through an amide group (-CONH). Para-aramid fibers have excellent properties such as high strength, high elasticity, and low shrinkage.The thin aramid fibers are 5mm thick and have a strong strength enough to lift 2 tons of cars. It is used for various purposes in the high-tech industry. In addition, aramid fibers are carbonized at 500 ° C or higher, and thus are attracting attention in fields requiring high heat resistance.

Aramid fiber is a process for producing a wholly aromatic polyamide polymer by polymerizing an aromatic diamine and an aromatic dieside halide in a polymerization solvent containing N-methyl-2-pyrrolidone, dissolving this polymer in a concentrated sulfuric acid solvent to prepare a spinning dope After the step of spinning through the spin dope through the spinneret to pass through the non-coagulant fluid and the coagulation bath sequentially to produce a filament, and the step of washing and drying the filament is produced.

Aramid pulp, on the other hand, has been prepared using aramid filaments prepared by conventional methods, more specifically, aramid chopped fibers are milled in water between two rotating disks to form fibrillated fibers. And then by a hydrofibrillation method for producing pulp by dehydration, or a dry fibrillation method for dry pulp by dry milling aramid fibers between a rotary cutter and a screen.

However, a variety of aramid waste dope and the cut filament mortality occurs during the process for producing the aramid filament, conventionally there was no way to recycle the aramid waste dope and the yarn as it was discarded as it is.

In addition, waste aramids such as fabrics, non-woven fabrics, and cables that are discarded after a long time by using aramid filaments and used for a long time are increasingly generated, and conventionally, there is no way to recycle such waste aramids. Has been causing serious environmental problems.

The present invention was derived to solve the above problems, the present invention is to recycle the waste dope and waste filaments generated during the process of manufacturing the aramid filament and a large amount of waste aramid discarded after use in the product without disposal On the other hand, it aims at providing the aramid pulp which has the outstanding physical property calculated | required by the industry, and its manufacturing method.

In order to achieve the above object, the present invention is prepared using waste aramid short fibers, the waste aramid short fibers are prepared from aramid waste dope (waste dope) and aramid pulp prepared using the waste aramid short fibers cross-sectional area Aramid pulp is characterized in that the deviation of 3 to 100% and the degree of freedom is 300 to 400ml.

Another invention is prepared using waste aramid short fibers, wherein the waste aramid short fibers are prepared from recycled aramid and the aramid pulp prepared using the waste aramid short fibers has a content of foreign matter less than 5% by weight It relates to an aramid pulp, characterized in that the degree of freedom is 300-400 ml.

On the other hand, the recycled aramid of the present invention may be cut filament, waste yarn, waste fabric and waste nonwoven fabric.

In addition, the present invention can be made by mixing the discarded aramid short fibers and aramid short fibers prepared from a conventional aramid filament.

In another aspect of the invention, the step of preparing the waste aramid short fibers; and

Washing the waste aramid short fibers; and dissociating the washed waste aramid short fibers in water to prepare a slurry; and preparing aramid pulp comprising a beating step of fibrillating the slurry. Provide a method.

On the other hand, the present invention may further comprise the step of neutralizing the pulverized waste aramid short fibers after the pulverized waste dope to manufacture the short aramid short fibers from the waste dope (waste dope) to produce a short fiber. .

In addition, the present invention is to prepare the waste aramid short fibers from the recycled aramid, the washing step, the step of injecting the waste aramid short fibers into the cleaning solution containing a surfactant; and the inside of the cleaning unit while stirring the cleaning solution The step of cleaning the air by blowing to the; and when the cleaning is completed may include the step of draining and washing the washing liquid.

In addition, the present invention may further comprise the step of making paper from the fibrillated slurry after the beating step, removing and drying moisture from the paper and crushing the dried paper into a plurality of pieces. Can be.

In addition, the present invention can be used by mixing the aramid short fibers prepared from conventional aramid filament in each step described above.

According to the present invention, by producing the aramid pulp by using the waste aramid, it is possible to omit the treatment cost by recycling the waste discarded in the manufacturing process, and to prepare a cheap aramid pulp, as well as to reduce the environmental pollution.

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 and scope of the invention. Accordingly, the invention includes all modifications and variations that fall within the scope of the invention as set forth in the claims and their equivalents.

As used herein, the term 'regenerated aramid' refers to aramid used by recycling cut aramid filaments, used cables, fabrics, nonwoven fabrics, and the like.

Hereinafter, an embodiment of the aramid pulp of the present invention and a method for producing the same will be described in detail with reference to the accompanying drawings.

First, aromatic polyamide polymers for preparing aramid filaments are prepared by the method described below.

An inorganic salt is added to the organic solvent to prepare a polymerization solvent. As the organic solvent, an amide organic solvent, a urea organic solvent, or a mixed organic solvent thereof may be used. Specific examples thereof include N-methyl-2-pyrrolidone (NMP), N, and N'-dimethylacetate. Amide (DMAc), hexamethylphosphoramide (HMPA), N, N, N ', N'-tetramethyl urea (TMU), N, N-dimethylformamide (DMF) or mixtures thereof.

Next, an aromatic diamine is dissolved in the prepared polymerization solvent to prepare a mixed solution. Specific examples of aromatic diamines include para-phenylenediamine, 4,4'-diaminobiphenyl, 2,6-naphthalenediamine, 1,5-naphthalenediamine or 4,4'-diaminobenzanilide. However, the present invention is not limited thereto.

Subsequently, while stirring the mixed solution, a predetermined amount of aromatic dieside halide is added to the mixed solution to prepolymerize. Specific examples of aromatic dieside halides include, but are not limited to, terephthaloyl dichloride, 4,4'-benzoyl dichloride, 2,6-naphthalenedicarboxylic acid dichloride or 1,5-naphthalenedicarboxylic acid dichloride. It doesn't happen.

After the completion of the prepolymerization process, the temperature is lowered to 0 to 10 ° C. and an aromatic dieside halide is further added to the prepolymer to prepare a final polymer.

Specific examples of the aromatic polyamide polymer obtained by the polymerization step include poly (paraphenylene terephthal-amide: PPD-T), poly (4,4'-benzanilide terephthalamide), poly (paraphenylene-4, 4'-biphenylene-dicarboxylic acid amide) or poly (paraphenylene-2,6-naphthalenedicarboxylic acid amide).

Subsequently, the acid produced during the polymerization reaction is neutralized with an alkali compound.

Since the aromatic polyamide polymer obtained through the polymerization reaction is present in the form of bread crumb, the flowability of the aromatic polyamide solution is poor. Therefore, in order to improve the fluidity, it is preferable to proceed with the subsequent process in the state of making the slurry by adding water to the aromatic polyamide solution. On the other hand, when the aromatic polyamide polymer slurry is made, the neutralization process may be simultaneously performed by using water in which the alkali compound is dissolved.

Subsequently, the aromatic polyamide polymer from which the acid is removed by the neutralization step is pulverized. Next, the polymerization solvent is extracted from the pulverized aromatic polyamide polymer.

Next, the remaining water after the extraction step is dehydrated, and then the drying process is completed to complete the production of the aromatic polyamide polymer.

Spinning dope is prepared by dissolving the aromatic polyamide polymer prepared as above in a concentrated sulfuric acid solvent having a concentration of 97 to 100%. Instead of the concentrated sulfuric acid, chloro sulfuric acid, fluoro sulfuric acid and the like may also be used.

Next, as shown in FIG. 1, the process of manufacturing an aramid filament is demonstrated.

The spinning dope is spinned using a spinneret 10 and then filaments are formed by coagulation in a coagulation bath 20 through an air gap.

Next, sulfuric acid remaining in the obtained filament is removed.

Sulfuric acid remaining in the filament may be removed through a washing process using water or a mixed solution of water and an alkaline solution. The washing process may be carried out in a multi-step process, for example, first washing the filament containing sulfuric acid in the first washing tank 30 containing the aqueous solution of caustic soda, and then thinner than the first washing tank 30 The second washing in the second washing tank 40 containing the aqueous solution of caustic soda is.

Subsequently, a drying process for removing moisture remaining in the filament is performed in the drying unit 50, and the dried filament is wound by the winder 60.

The waste aramid short fibers of the present invention can be prepared from a variety of materials, for example, waste doped and cut filaments generated during the spinning and weaving process can be used, or cables, fabrics, nonwoven fabrics, etc. used for a long time can be recycled. .

In the spinning process, a large amount of waste dope is thrown out through the spinneret. Since the waste dope contains sulfuric acid, it is classified as a hazardous industrial waste and must be disposed of according to strict regulations. Therefore, enormous cost is required to dispose of the waste dope and it has contaminated the environment in the process of disposal.

Accordingly, the present invention intends to use the waste dope to produce aramid pulp by recycling it without waste disposal as in the prior art.

In addition, in the case of performing the weaving process, a large amount of dead sand, which is a filament cut by process instability, is generated. The waste sand has also been disposed of in the past like waste dope.

In the present invention, in order to recycle the waste dope to produce aramid pulp, first, the waste dope in a large agglomerate state is pulverized to an average size of about 10 g using a grinder. If the waste dope is used in the form of a large mass without pulverizing small as in the present invention, the dispersion does not proceed smoothly in the dissociation process, and thus, the fibrillation does not occur smoothly in the dissociation process.

On the other hand, the pulverized waste dope is preferably neutralized using an aqueous solution of caustic soda. Since the waste dope contains a high concentration of sulfuric acid of about 97%, if the process is carried out in the above state, the mechanical life used during the process is corroded to shorten the life of the machine. In addition, when the aramid pulp, which is the final product, contains a large amount of sulfuric acid, the molecular weight of the aramid polymer is gradually lowered, thereby deteriorating the physical properties of the product.

Then, the cut filaments and the like are cut by using a rotary cutter (not shown) to produce the waste aramid short fibers 1 having a length of about 3 to 10 mm. The length of the waste aramid short fibers 1 can be adjusted by adjusting the blade spacing of the rotary cutter.

In addition, the present invention can produce the waste aramid short fibers (1) by cutting or grinding recycled aramid, such as fabric, cable, nonwoven fabric discarded for a long time.

Next, the present invention can produce aramid pulp from waste aramid short fibers as shown in Figure 2, washing process, dissociation process, beating process, papermaking process and water removal process, crushing process and packaging process, etc. It can manufacture by including.

First, the washing process will be described in detail. The aramid short fibers prepared as described above are introduced into the washing tank 110 containing the washing liquid 111. If the waste aramid short fibers prepared from waste dope are used, it may be preferable to neutralize and wash with caustic soda aqueous solution. In the cleaning process, it may be preferable to use a cleaning solution 111 containing a surfactant to clean the solution while stirring at room temperature or higher.

On the other hand, the waste aramid short fibers (1) made from recycled aramid such as bulletproof products may contain a large amount of various kinds of foreign matter. If the dissociation and beating process is carried out in a state in which the foreign matter is contained in a large amount, the fibrillation may not be performed smoothly, and thus the physical properties of the manufactured aramid pulp may not meet the demands of the industry. Accordingly, in the present invention, it may be preferable to perform cleaning as in the embodiment of FIG. 3.

As shown in FIG. 3, the waste aramid short fibers 1 are introduced into the washing tank 110 containing the cleaning liquid 111, and a rotary blade connected to the motor rotates to sufficiently clean the waste aramid short fibers. Stir to At this time, the air generated through the air generating unit 130 such as an air pump is introduced into the cleaning tank 110 through the air inlet 131, so that a large amount of bubbles are generated to remove foreign substances attached to the waste aramid short fibers. Remove more smoothly

On the other hand, the air inlet 131 is installed in the cleaning tank 110 to impart air to the cleaning liquid 111. At this time, the air inlet is preferably adjusted to be supplied at 20 to 80% by volume per second compared to the short aramid fibers. When the air inflow amount is less than the above range, the amount of bubbles generated is low, the cleaning effect is reduced, and when the air inflow amount is too large, the cleaning effect is rather deteriorated due to excessive foam.

As for the temperature of the said washing | cleaning liquid 111, 30-90 degreeC is preferable. If the temperature is too low, the speed of decomposing and removing foreign matters is slow, and the cleaning effect is reduced. If the temperature is too high, the cleaning effect is not large, but only the energy cost is increased.

The cleaning liquid 111 includes a surfactant, and the surfactant may be used in all of the nonionic, cationic and anionic systems, but may be used in the present invention, but in terms of cleaning efficiency, anionic and cation may be used. It may be more desirable to use surfactants of the type.

After the cleaning is completed, the washing liquid 111 is discharged and washed with water.

Next, after the cleaning process, the waste aramid short fibers are dispersed in water in the dissociation unit 200 to prepare a homogeneous slurry. The dissociation step is preferably carried out at a temperature higher than room temperature. When the dissociation process is completed, waste aramid short fibers are separated and dispersed, respectively. The concentration of short aramid fibers in the slurry is preferably about 2.0%.

When the aramid slurry is formed by the dissociation process, the aramid slurry is sent to the beating part 300 to perform a refining process of tapping short aramid fibers contained in the slurry. A refiner (refiner) is installed in the high portion 300 to separate the undispersed aramid short fibers in the slurry, as well as to cut and fibrillate.

The beating process, on the other hand, is one of the important processes for determining the freeness (Canada Standard Freeness) of aramid pulp. This is because the degree of fibrillation of the aramid short fibers through the beating process shows a great difference in the degree of freedom of the aramid pulp. That is, if the degree of fibrillation is excellent, the freeness of the pulp is lowered, which means that the aramid pulp has excellent dispersibility. On the other hand, if the degree of fibrillation is poor, the degree of freeness of the pulp is high, which means that the aramid pulp has poor dispersibility.

The waste aramid short fibers prepared from the waste dope of the present invention are less oriented in crystallization than the aramid short fibers made of the aramid filament wound through the usual spinning process, so that fibrillation is not easily produced.

Therefore, it may be desirable to perform the beating process under more severe conditions, or to repeat the beating process several times.

Next, the slurry containing the fibrillated waste aramid short fibers through the beating process is made into a sheet by the paper making unit 400, and removes water from the water removing unit 500. do. Moisture removal is to first remove the moisture from the paper by using the upper and lower two squeegee roll, and then to dry the dehydrated paper (4) to the dry unit 520 to have a constant moisture content.

The dried papermaking 5 is then crushed in a crushing unit 600 to become the final aramid pulp 6.

The final aramid pulp 6 thus prepared is compressed in a predetermined unit in a wrapping unit 700 and then transported to a destination.

The aramid pulp 6 produced is composed of a stem 6a and a plurality of fibrils 6b branched from the stem 6a, as shown in FIG. Consists of brills. On the other hand, the aramid pulp of the present invention prepared from the closed dope with poor orientation crystallinity is severely different in cross-sectional area, unlike the aramid pulp produced by the conventional method as shown in FIG. However, in order to meet the physical properties required in the industry, it is preferable that the rate of change of the cross-sectional area of the aramid pulp produced from the waste dope is 3 to 100%. If the rate of change in cross-sectional area is too large, the fibrillation variation of aramid pulp is severely generated, and the variation in physical properties also occurs in products using such aramid pulp, so it is preferable that the maximum cross-sectional area variation is not exceeded. Aramid pulp having a cross-sectional area variation of 3 to 100% as described above will meet the 300 to 400 ml range required by the industry.

In addition, the waste aramid short fibers (1) prepared from the recycled aramid of the present invention by thoroughly removing the foreign matter through the above-described cleaning process, the aramid pulp (6) produced has a content of foreign matter less than 1% and Yeosu The degree is in the range of 300 to 400 ml.

However, aramid pulp prepared using the waste aramid short fibers 1 of the present invention may be inferior in physical properties to aramid pulp prepared from aramid filaments. Therefore, aramid pulp can also be manufactured by mixing the aramid manufactured by the conventional method in one or more of the above-mentioned steps.

Hereinafter, the present invention will be described in detail through examples and comparative examples.

Example  One

Spinning dope was prepared by dissolving an aromatic polyamide polymer having an intrinsic viscosity (IV) of 5.1 in 100% sulfuric acid solvent. Waste dope discarded during the process of spinning the spin dope through the spinneret was collected and pulverized in a pulverizer to prepare waste aramid short fibers having a mass of 6 g of the average pulverized product.

The waste aramid short fibers (1) were neutralized in a 2% aqueous solution of caustic soda and washed with pure water at 50 ° C., and then 100 kg of the waste aramid short fibers was dispersed in 10,000 L of pure water to prepare a homogeneous slurry. The slurry thus prepared was introduced into a beaker 300 equipped with a double disk refiner, and then beaten for 60 minutes to produce fibrillated waste aramid short fibers 2.

After the beating process, the fibrillated slurry was made into a form of paper 3, water was removed from the squeegee roll 510, and the paper was dried in the drying unit 520 under a temperature of 100 ° C. for 5 minutes.

The dried papermaking 5 was crushed into small pieces using a grinder to produce the final aramid pulp 6.

Example  2

Aromatic polyamide polymer having an intrinsic viscosity (IV) of 5.1 is dissolved in 100% sulfuric acid solvent, the spinning dope is spun through spinneret, solidified, and then washed with water and dried to cut ordinary aramid filament using a rotary cutter. To prepare aramid short fibers. After washing the prepared aramid short fibers in 50 ℃ pure water, 100 kg of the aramid short fibers were dispersed in 10,000 L of pure water to prepare a homogeneous slurry. The slurry thus prepared was introduced into a high-discharge part 300 equipped with a double disk refiner, and then solidified for 60 minutes to produce fibrillated aramid short fibers.

After the beating process, the conventional fibrillated slurry and the fibrillated slurry prepared from the waste dope according to Example 1 were mixed at 50:50 to form a paper form, and then water was removed from the squeegee roll 510. The paper was dried in the drying unit 520 for 5 minutes at a temperature of 100 ° C.

The dried paper was crushed into small pieces using a grinder to produce the final aramid pulp.

Comparative example  One

The aramid pulp was prepared in the same manner as in Example 1 except that the waste dope was collected and ground in a grinder to use waste aramid short fibers having an average mass of 15 g.

Freeness and cross-sectional area variation of the aramid pulp prepared by Examples 1 and 2 and Comparative Example 1 was measured by the following method, and the results are shown in Table 1.

Example  3

The waste aramid short fibers 1 of 3 to 10 mm were made by cutting the discarded body armor containing 10 wt% or more of foreign matter using a cutter. The waste aramid short fibers were introduced into the washing tank 110 including the washing liquid 111 containing the anionic surfactant and stirred at a temperature of 60 ° C., while the air generated by the air pump was compared with the volume of the regenerated aramid short fibers. Into the cleaning liquid 111 at an air inflow rate of 50% per second was washed for 30 minutes. Thereafter, the washing liquid 111 was discharged through the outlet, and washed twice with pure water.

100 kg of the washed waste aramid short fibers was dispersed in 10,000 L of pure water to prepare a homogeneous slurry. The slurry thus prepared was introduced into a beating portion 300 equipped with a double disk refiner having a 20 inch diameter disk, and then beaten for 60 minutes to obtain fibrillated waste aramid short fibers 2 having an average length of 1 mm. Generated.

The fibrillated slurry is made into a papermaking 3 through a beating process, and then passed through two squeegee rolls 510 to remove water contained in the papermaking paper. Dry for 5 minutes under temperature.

The dried papermaking was crushed into small pieces using a grinder to produce the final aramid pulp 6.

Example  4

After the washing step, an aramid pulp was prepared in the same manner as in Example 3 except that the aramid short fibers having 3 to 10 mm prepared by the conventional method described in Example 2 were mixed and used.

Comparative example  2

Aramid pulp was prepared in the same manner as in Example 3, except that the air inflow amount was added to the cleaning liquid 111 at an air inflow amount of 5% per second compared to the volume of aramid short fibers.

Comparative example  3

Aramid pulp was prepared in the same manner as in Example 3 except that the temperature of the cleaning unit 100 was not heated in the cleaning process.

The freeness and foreign matter content of the aramid pulp prepared by Examples 3 to 4 and Comparative Examples 2 to 3 described above are shown in Table 2 by measuring by the following method.

Freedom Measurement of Aramid Pulp

Freeness (ml) of aramid pulp was measured by the Canadian Standard Freeness (CSF) test method of KS M ISO 5267-2, and the results are shown in Table 1.

Measurement of the Cross-sectional Fluctuation of Aramid Pulp

After molding the aramid pulp with paraffin, cut the cross section with a knife to prepare a sample, except for the fibril portion of the prepared sample, only the cross section of the stem portion of the image analyzer (in the software of Image-Pro Plus, JVC Digital Camera KY -F70B) was used to automatically measure the cross-sectional area variation.

Foreign substance content measurement

Remove the foreign substance such as oil by using the aramid pulp prepared by acetone or DMF organic solvent, and remove the foreign substance such as soil by sinking in aqueous solution, and remove the foreign substance which is not dyed by dyeing with acid dye. Other aramid pulp by raising the temperature before the decomposition temperature was removed to remove the foreign matter having a low decomposition temperature, was measured by comparing the aramid pulp weight before removing the foreign matter.

division Example 1 Example 2 Comparative Example 1 Yeosu-do (ml) 390 370 500 % Cross-sectional area 37 18 45

As shown in Table 1, it can be seen that the aramid pulp prepared from the waste dope having poor orientation crystallinity has a lower degree of freedom than the aramid pulp prepared by mixing the aramid short fibers prepared from conventional aramid filaments.

On the other hand, if the size of the waste aramid short fibers is too large, fibrillation does not proceed smoothly it can be seen that the degree of freedom is significantly reduced.

division Example 3 Example 4 Comparative Example 2 Comparative Example 3 Yeosu-do (ml) 370 360 450 420 Foreign substance content (wt%) 0.5 0.2 6 9

As shown in Table 2, the present invention subjected to a thorough cleaning process as described in the present invention using waste aramid short fibers prepared from recycled aramid has a low foreign matter content, smooth fibrillation proceeds, the excellent Yeosu required in the industry It can be seen that it has a degree.

On the other hand, if the cleaning process is not carried out thoroughly, the waste aramid short fibers (1) has a high content of foreign matters, and thus, fibril does not proceed smoothly during the beating process, and thus, even Yeosu, which is required by the industry, does not meet the physical properties. .

Figure 1 schematically shows a process for producing aramid filament according to an embodiment of the present invention.

Figure 2 schematically shows a process for producing aramid pulp according to an embodiment of the present invention.

3 schematically illustrates a cleaning process according to an embodiment of the present invention.

Figure 4 is an enlarged side view of aramid pulp prepared from waste dope which is one embodiment of the present invention.

FIG. 5 is a cross-sectional view of the stem portion of the aramid pulp of FIG. 4. FIG.

<Description of Signs of Major Parts of Drawings>

1: Waste Aramid Short Fiber 6: Aramid Pulp

100: tax government 110: washing tank

111: cleaning liquid 130: air generation unit

200: dissociation part 300: high anatomy

400: grass forming part 500: moisture removal part

600: shredding part 700: packing part

Claims (9)

Prepared using waste aramid short fibers, the waste aramid short fibers are prepared from aramid waste dope (waste dope) and aramid pulp prepared using the waste aramid short fibers has a cross-sectional variation of 3 to 100% and Yeosu Aramid pulp, characterized in that 300 to 400ml. Prepared using waste aramid short fibers, the waste aramid short fibers are prepared from recycled aramid, and aramid pulp prepared using the waste aramid short fibers has a content of foreign matter less than 5% by weight and the degree of freedom 300-400 Aramid pulp, characterized in that ml. The method of claim 2, The regenerated aramid is aramid pulp, characterized in that the cut filament, waste yarn, waste fabric and waste nonwoven fabric. The method according to any one of claims 1 to 3, Aramid pulp, characterized in that the aramid short fibers made from the waste aramid short fibers and ordinary aramid filaments are mixed. Preparing waste aramid short fibers; and Washing the waste aramid short fibers; and Dissociating the washed waste aramid short fibers in water to prepare a slurry; and A method for producing aramid pulp, characterized in that it comprises a beating step of fibrillating the slurry. The method of claim 5, When the waste aramid short fibers are manufactured from waste dope, the aramid pulp is characterized by further comprising the step of neutralizing the pulverized waste aramid short fibers after the waste dope is ground to prepare short fibers. Manufacturing method. The method of claim 5, In the case of producing the waste aramid short fibers from the recycled aramid, the washing step, the step of injecting the waste aramid short fibers into the cleaning solution containing a surfactant; and blowing the air into the cleaning unit while stirring the cleaning solution And a step of draining and washing the washing liquid when the washing is completed. The method of claim 5, Aramid further comprising: after the beating step, making paper from the fibrillated slurry; removing and drying moisture from the paper; and crushing the dried paper into a plurality of pieces. Method for producing pulp. The method according to any one of claims 6 to 8, A method for producing aramid pulp, characterized in that a mixture of aramid short fibers prepared from ordinary aramid filaments are used.

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