WO2017026748A1 - High-elongation copolymerized aramid fiber - Google Patents

Abstract

A high-elongation copolymerized aramid fiber of the present invention comprises an aramid copolymer comprising a cyano group(-CN)-substituted aromatic group and has an elongation of 4.0-6.5%, a crystallinity of 30-55%, and a crystal size of 15-40Å(200 planes). The present invention comprises an aramid copolymer comprising a cyano group(-CN)-substituted aromatic group, the fiber structure thereof is loosely formed, and the crystallinity and crystal size thereof are small, and thus the elongation of the aramid fiber is significantly improved to 4.0-6.5% while having a high strength property as an intrinsic characteristic of an aramid fiber. The present invention is useful as a material for various products requiring both a high strength property of the aramid fiber as well as a high elongation property at the same time.

Description

High Elongation Copolymer Aramid Fiber

The present invention relates to a high-strength copolymerized aramid fiber, specifically, consisting of an aramid copolymer containing an aromatic group substituted with a cyano group (-CN), loose fiber structure, crystallinity and crystal size is small, high elongation It relates to the copolymerized aramid fiber to be provided.

Aramid fibers include para-aramid fibers and meta-aramid fibers. Among them, para-aramid fiber has excellent properties such as high strength, high elasticity, and low shrinkage. Especially, it has a strong strength enough to lift a 2 ton car with a thin thread of about 5mm thick, and is not only used for bulletproof applications. It is used for various purposes in high-tech industries such as aerospace.

Aramid fibers are typically (i) spinning the aramid spinning dope (Dope) through the spinneret 20, as shown in Figure 1, and (ii) coagulating the spun aramid fibers with the coagulation bath (30) Solidification while passing through the solidification tube 40 is injected into the solidification process, and (iii) the solidified aramid fibers passing through the at least one flush roller 50 as shown in FIG. The washing process by spraying the washing liquid to the aramid fibers passing through the washing roller (50) through the washing liquid injection nozzle (90), and (iv) drying the washed aramid fibers with a drying apparatus 70 and then wound up It is manufactured through a series of winding process in the roller (80).

In this case, as an example of a method for producing the aramid spinning dope (Dope) as described in Korean Patent No. 10-0910537 aromatic diamine such as paraphenylenediamine dissolved in an organic solvent to which inorganic salts are added and mixed Prepare a solution, and add aromatic diacid halides such as terephthaloyl dichloride to the mixed solution. After reacting to prepare an aramid polymer, the prepared aramid polymer was dissolved in sulfuric acid to prepare a spinning dope.

The organic solvent may be N-methyl-2-pyrrolidone (NMP), N, N'-dimethylacetamide (DMAc), hexamethylphosphoamide (HMPA), N, N, N ', N'-tetra Methyl urea (TMU), N, N-dimethylformamide (DMF) or mixtures thereof may be used. As the inorganic salt, CaCl ₂ , LiCl, NaCl, KCl, LiBr, KBr, or a mixture thereof may be used.

The aromatic diamine may be para-phenylenediamine, 4,4'-diaminobiphenyl, 2,6-naphthalenediamine, 1,5-naphthalenediamine, or 4,4'-diaminobenzanilide.

The aromatic dieside halide may be terephthaloyl dichloride, 4,4'-benzoyl dichloride, 2,6-naphthalenedicarboxylic acid dichloride, or 1,5-naphthalenedicarboxylic acid dichloride.

The aramid polymer may be polyparaphenylene terephthalamide, poly (4,4'-benzanilide terephthalamide), poly (paraphenylene-4,4'-ratio depending on the type of aromatic diamine and aromatic dieside halide used. Phenylene-dicarboxylic acid amide), or poly (paraphenylene-2,6-naphthalenedicarboxylic acid amide).

As another example of preparing the aramid spinning dope (Dope) as described in Korean Patent No. 10-171994, paraphenylenediamine and cyano-para-phenylene diamine is dissolved in an organic solvent Terephthaloyldichloride was added and reacted to prepare a spinning dope comprising a copolymer aramid polymer containing an aromatic group substituted with a cyano group (-CN). In this case, there is an advantage that the copolymer aramid polymer can be produced by spinning dope (Dope) without the process of dissolving in sulfuric acid.

Conventional aramid fibers prepared by the methods described above is a product material that requires high strength and high elongation characteristics inherent in aramid fibers because the elongation is less than 4% because of the dense fiber structure and large crystallinity and crystal size. There were limitations that were difficult to use.

An object of the present invention is to provide a high-strength aramid copolymer aramid fibers composed of an aramid copolymer containing an aromatic group substituted with a cyano group (-CN) excellent in elongation 4.0 to 6.5%.

In order to achieve the above object, in the present invention, the organic solvent remaining in the aramid fiber is rapidly extracted during the coagulation step and the washing step for producing the aramid fiber, thereby reducing the crystallinity and crystal size of the aramid fiber and loosening the structure of the aramid fiber. Raise your congregation.

The present invention consists of an aramid copolymer comprising an aromatic group substituted with a cyano group (-CN), the fiber structure is loosely formed, crystallinity and crystal size is small, so that the elongation is 4.0 to 6.5% This is greatly improved.

The present invention is useful as a material for various products in which high strength properties and high elongation properties of aramid fibers are simultaneously required.

1 is a process schematic diagram of making aramid fibers.

2 is a cross-sectional view of a flush roller used in an embodiment of the present invention.

Figure 3 is a schematic view of the process of washing the aramid fibers using the flushing roller of Figure 2 in the present invention.

Figure 4 is a schematic view of the process of washing the aramid fibers by the conventional method.

Hereinafter, the present invention will be described in detail with reference to the accompanying drawings.

The high-strength copolymerized aramid fiber according to the present invention is composed of an aramid copolymer containing an aromatic group substituted with cyano group (-CN), elongation 4.0 to 6.5%, crystallinity 30 to 55%, crystal size 15 to 40Å It is characterized by (200 pages).

The present invention consists of an aramid copolymer comprising an aromatic group substituted with a cyano group (-CN) elongation 4.0 to 6.5%, crystallinity 30 to 55%, crystal size 15 to 40Å (200 planes), strength It contains the high elongation copolymer aramid fiber which is 18-25 g / d.

The present invention consists of an aramid copolymer containing an aromatic group substituted with a cyano group (-CN) elongation 4.0 to 6.5%, crystallinity 30 to 55%, crystal size 15 to 40Å (200 planes), elastic modulus The high elongation copolymer aramid fiber which is 400-600 g / d is included.

The present invention consists of an aramid copolymer comprising an aromatic group substituted with a cyano group (-CN) elongation 4.0 to 6.5%, crystallinity 30 to 55%, crystal size of 15 ~ 40Å (200 planes) and 5 ~ High-strength copolymerized aramid fibers of 20 microseconds (110 faces).

The aramid copolymer including the aromatic group substituted with the cyano group (-CN) has a repeating unit of the following general formula (I).

[In Formula (I), Ar is an aromatic group of the following general formula (II), and A is an aromatic group of the following general formula (III) or an aromatic group of the general formula (II) Is an aromatic group having a ratio of 1: 9-9: 1]

Various physical properties of the high elongation copolymer aramid fibers according to the present invention were evaluated by the following method.

Crystallinity ( % )

The diffraction pattern obtained through X-ray analysis was used to determine the ratio between the peak peak and the amorphous peak.

Crystal size (Å)

The full width at half maximum (FWHM) was obtained using the diffraction pattern obtained through the X-ray analysis and calculated using the Scherrer equation.

Strength (g / d), elongation ( % ) And Modulus (g / d)

Tensile properties of aramid fibers were measured according to the ASTM D885 test method. Specifically, the physical properties of the fiber were obtained by pulling until the copolymer aramid fiber having a length of 25 cm was broken in an Instron Engineering Corp. (Cantion, Mass).

At this time, the tensile speed was 300 mm / min, the ultra-load was fineness × 1 / 30g. The number of samples was calculated | required as the average value after testing five. The modulus of elasticity was obtained from the slope on the S-S curve, the strength was the maximum load at break, and the elongation was calculated from the length at break.

Next, an example of the manufacturing method of the high elongation copolymer aramid fiber of this invention is examined.

The following preparation method is merely an example of the preparation of the high-strength copolymerized aramid fibers of the present invention and should not be construed as limiting the protection scope of the present invention.

First, the present invention performs the step of preparing a spinning dope for producing aramid fibers. Specifically, an inorganic salt is added to the organic solvent to prepare a polymerization solvent, and then paraphenylenediamine and cyano-para-phenylenediamine are dissolved together in the organic solvent or cyano-para-phenylenediamine alone. After dissolving the mixture, a mixed solution was prepared, followed by primary polymerization by adding a small amount of terephthaloyldichloride to the mixed solution while stirring the mixed solution to form a prepolymer in the polymerization solvent.

Thereafter, terephthaloyldichloride was further added to the polymerization solvent to carry out the second polymerization to obtain a spinning dope for preparing aramid, in which a copolymerized aramid copolymer containing an aromatic group substituted with a cyano group (-CN) was dissolved in an organic solvent. Manufacture.

At this time, the organic solvent is N-methyl-2-pyrrolidone (NMP), N, N'- dimethylacetamide (DMAc), hexamethylphosphoramide (HMPA), N, N, N ', N' -Tetramethyl urea (TMU), N, N-dimethylformamide (DMF) or mixtures thereof can be used. The inorganic salt may be used a mixture of _{CaCl 2, LiCl, NaCl, KCl} , LiBr, KBr, or mixtures thereof.

Next, after spinning the spinning dope (Dope) prepared as described above as shown in Figure 1 through the spinneret 20, the coagulated bath 30 and the coagulating liquid is injected to the spun aramid fibers After passing through the coagulation tube (40) in turn, the coagulated aramid fibers pass through the water washing roller (50, 60) in turn and washed with water, dried with a drying apparatus (70) and then wound in a winding roller (80) to obtain a high degree of copolymerization Prepare aramid fibers.

In this embodiment, (i) water (pure) at 20 to 60 ° C is used as the coagulating solution, and (ii) water (pure) at 30 to 70 ° C is used as the washing liquid in the washing step. , (iii) as shown in FIG. 2, a washing liquid injection hole 51 is formed on the surface of the washing liquid to inject the washing liquid by centrifugal force generated by the rotation of the washing roller 50, and the washing roller 50 is formed inside the washing roller 50. A hollow washing liquid supply pipe 52 is formed in a concentric circle with the outer periphery of the washing roller 50, and the washing liquid injection ports 51 communicate with the washing liquid supply pipe 52. 50) is used to quickly extract the organic solvent remaining in the aramid fibers (Y).

When the aramid fiber (Y) passes over the flushing roller (50), the flushing liquid contained in the flushing liquid supply pipe (52) formed inside the flushing roller (50) as shown in Figure 3 flushing roller (50) By the centrifugal force generated by the rotation of the water is sprayed in the direction of the aramid fiber (Y) through the washing liquid injection port 51 formed on the surface of the water washing roller (50).

Therefore, the jetted washing solution can penetrate smoothly into the inside of the aramid yarn Y passing through the washing roller 50, thereby quickly extracting the organic solvent remaining in the aramid fiber Y.

In this way, if the organic solvent remaining in the aramid fibers (Y) is quickly extracted, the structure of the fibers is loosened, the crystallinity and crystal size are also reduced, and the elongation of the fibers is greatly improved.

Further, in the exemplary embodiment of the present invention, since the coagulating liquid and the washing liquid use water (pure water) that maintains a temperature higher than room temperature, the organic solvent remaining in the aramid fiber (Y) is quickly extracted.

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

However, the following examples are only examples of preferred embodiments of the present invention and should not be construed as limiting the protection scope of the present invention.

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 p-phenylenediamine and cyano-para- 50 mol% of phenylenediamine (cyano-p-phenylenediamine) was added to the reactor and dissolved to prepare a mixed solution.

Subsequently, 100 mol% of terephthaloyl dichloride was added to the reactor containing the mixed solution to prepare a spinning dope including a copolymerized aramid polymer.

Subsequently, as shown in FIG. 1, after the spinning dope is spun through the spinneret 20, the spun copolymerized aramid fibers are spun with a coagulation bath 30 and 40 ° C. containing 40 ° C. water (coagulant). After coagulation while passing through the coagulation tube 40 to which water (coagulation liquid) is injected, the coagulated aramid fiber passed through the coagulation tube 40 is continuously flushed to the surface of the water washing roller 50 as shown in FIGS. 2 and 3. Washing liquid injection holes 51 are formed to inject the washing liquid with the centrifugal force generated by the rotation, and the washing liquid which is hollow while forming a concentric circle with the outer circumference of the washing roller 50 inside the washing roller 50. A supply pipe 52 is formed, and the injection holes 51 pass through the flushing roller 50, which is in communication with the flushing liquid supply pipe 52, to the flushing liquid supply pipe 52 formed inside the flushing roller 50. Washing liquid with 50 degreeC water The process of spraying water by spraying toward the copolymerized aramid fibers passing through the washing roller 50 through the washing liquid injection port 51 formed on the surface of the washing roller 50 by the centrifugal force generated by the rotation of the roller 50 is performed. After the aging, it was dried with a drying apparatus 70 and wound on a winding roller 80 to produce copolymerized aramid fibers. The results of evaluating various physical properties of the prepared copolymer aramid fibers were as shown in Table 1.

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 100 mol% of cyano-p-phenylenediamine was added. Into the reactor was dissolved to prepare a mixed solution.

Subsequently, 100 mol% of terephthaloyl dichloride was added to the reactor containing the mixed solution to prepare a spinning dope including a copolymerized aramid polymer.

Subsequently, as shown in FIG. 1, after the spinning dope is spun through the spinneret 20, the spun copolymerized aramid fibers are spun with a coagulation bath 30 and 50 ° C. containing 50 ° C. water (coagulant). After coagulation while passing through the coagulation tube 40 to which water (coagulation liquid) is injected, the coagulated aramid fiber passed through the coagulation tube 40 is continuously flushed to the surface of the water washing roller 50 as shown in FIGS. 2 and 3. Washing liquid injection holes 51 are formed to inject the washing liquid with the centrifugal force generated by the rotation, and the washing liquid which is hollow while forming a concentric circle with the outer circumference of the washing roller 50 inside the washing roller 50. A supply pipe 52 is formed, and the injection holes 51 pass through the flushing roller 50, which is in communication with the flushing liquid supply pipe 52, to the flushing liquid supply pipe 52 formed inside the flushing roller 50. Washing liquid with 60 degrees Celsius of water The process of spraying water by spraying toward the copolymerized aramid fibers passing through the washing roller 50 through the washing liquid injection port 51 formed on the surface of the washing roller 50 by the centrifugal force generated by the rotation of the roller 50 is performed. After the aging, it was dried with a drying apparatus 70 and wound on a winding roller 80 to produce copolymerized aramid fibers. The results of evaluating various physical properties of the prepared copolymer aramid fibers were as shown in Table 1.

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 p-phenylenediamine and cyano-para- 50 mol% of phenylenediamine (cyano-p-phenylenediamine) was added to the reactor and dissolved to prepare a mixed solution.

Subsequently, 100 mol% of terephthaloyl dichloride was added to the reactor containing the mixed solution to prepare a spinning dope including a copolymerized aramid polymer.

Subsequently, as shown in FIG. 1, after the spinning dope is spun through the spinneret 20, the spun copolymerized aramid fibers are spun with a coagulation bath 30 and 40 ° C. containing 40 ° C. water (coagulant). After coagulation while passing through the coagulation tube 40 to which water (coagulation liquid) is injected, the coagulated aramid fiber passed through the coagulation tube 40 is continuously flushed to the surface of the water washing roller 50 as shown in FIGS. 2 and 3. Washing liquid injection holes 51 are formed to inject the washing liquid with the centrifugal force generated by the rotation, and the washing liquid which is hollow while forming a concentric circle with the outer circumference of the washing roller 50 inside the washing roller 50. A supply pipe 52 is formed, and the injection holes 51 pass through the flushing roller 50, which is in communication with the flushing liquid supply pipe 52, to the flushing liquid supply pipe 52 formed inside the flushing roller 50. Washing liquid with 50 degreeC water The process of jetting and washing with a centrifugal force generated by the rotation of the roller 50 toward the copolymerized aramid fiber passing through the washing roller 50 through the washing liquid injection port 51 formed on the surface of the washing roller 50 After the aging, it was dried with a drying apparatus 70 and wound on a winding roller 80 to produce copolymerized aramid fibers. The results of evaluating various physical properties of the prepared copolymer aramid fibers were as shown in Table 1.

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 was added. Into the reactor was dissolved to prepare a mixed solution.

Subsequently, 100 mol% of terephthaloyl dichloride was added to the reactor containing the mixed solution to prepare a spinning dope including a copolymerized aramid polymer.

Subsequently, as shown in FIG. 1, after the spinning dope is spun through the spinneret 20, the spun copolymerized aramid fibers are spun with a coagulation bath 30 and 40 ° C. containing 40 ° C. water (coagulant). After coagulation while passing through the coagulation tube 40 to which water (coagulation liquid) is injected, the coagulated aramid fiber passed through the coagulation tube 40 is continuously flushed to the surface of the water washing roller 50 as shown in FIGS. 2 and 3. Washing liquid injection holes 51 are formed to inject the washing liquid with the centrifugal force generated by the rotation, and the washing liquid which is hollow while forming a concentric circle with the outer circumference of the washing roller 50 inside the washing roller 50. A supply pipe 52 is formed, and the injection holes 51 pass through the flushing roller 50, which is in communication with the flushing liquid supply pipe 52, to the flushing liquid supply pipe 52 formed inside the flushing roller 50. Washing liquid with 50 degreeC water The process of jetting and washing with a centrifugal force generated by the rotation of the roller 50 toward the copolymerized aramid fiber passing through the washing roller 50 through the washing liquid injection port 51 formed on the surface of the washing roller 50 After the aging, it was dried with a drying apparatus 70 and wound on a winding roller 80 to produce copolymerized aramid fibers. The results of evaluating various physical properties of the prepared copolymer aramid fibers were as shown in Table 1.

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 p-phenylenediamine and cyano-para- 50 mol% of phenylenediamine (cyano-p-phenylenediamine) was added to the reactor and dissolved to prepare a mixed solution.

Subsequently, 100 mol% of terephthaloyl dichloride was added to the reactor containing the mixed solution to prepare a spinning dope including a copolymerized aramid polymer.

Subsequently, as shown in FIG. 1, the spinning dope was spun through the spinneret 20, and then the spun copolymerized aramid fiber was n-methyl-2-pyrrolidone (NMP) 10% aqueous solution (coagulant). The coagulation bath 30 contained therein and N-methyl-2-pyrrolidone (NMP) 10% aqueous solution (coagulation liquid) are coagulated while passing through the coagulation tube 40 to be injected, and then coagulation tube 40 is continued. Passing the copolymer aramid fibers passed through the washing roller 50 as shown in Figure 4 through the washing liquid jet nozzle 90 outside the top of the washing roller 50, the washing liquid of 15 ℃ water washing roller (50) (2) and then sprayed toward the copolymer aramid fibers passing through the water twice, and then dried with a drying apparatus 70 and wound in a winding roller 80 to prepare a copolymer aramid fibers. The results of evaluating various physical properties of the prepared copolymer aramid fibers were as shown in Table 1.

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 100 mol% of cyano-p-phenylenediamine was added. Into the reactor was dissolved to prepare a mixed solution.

Subsequently, 100 mol% of terephthaloyl dichloride was added to the reactor containing the mixed solution to prepare a spinning dope including a copolymerized aramid polymer.

Subsequently, as shown in FIG. 1, the spinning dope was spun through the spinneret 20, and then the spun copolymerized aramid fiber was n-methyl-2-pyrrolidone (NMP) 10% aqueous solution (coagulant). The coagulation bath 30 contained therein and N-methyl-2-pyrrolidone (NMP) 10% aqueous solution (coagulation liquid) are coagulated while passing through the coagulation tube 40 to be injected, and then coagulation tube 40 is continued. Passing the copolymer aramid fibers passed through the washing roller 50 as shown in Figure 4 through the washing liquid jet nozzle 90 outside the top of the washing roller 50, the washing liquid of 15 ℃ water washing roller (50) (2) and then sprayed toward the copolymer aramid fibers passing through the water twice, and then dried with a drying apparatus 70 and wound in a winding roller 80 to prepare a copolymer aramid fibers. The results of evaluating various physical properties of the prepared copolymer aramid fibers were as shown in Table 1.

division		Example 1	Example 2	Example 3	Example 4	Comparative Example 1	Comparative Example 2
Elongation (%)		4.5	5.5	4.0	6.5	2.8	3.2
Crystallinity (%)		37	42	30	55	57	59
Crystal size	(P. 200)	28	32	12	40	52	54
	(P. 110)	9	13	5	20	21	22
Strength (g / d)		20	22	26	30	19	21
Modulus		480	530	410	600	680	700

* Explanation of the sign

10: Extruder

20: spinneret

30: coagulation tank

40: coagulation tube

41: coagulation liquid jet

Y: Aramid Fiber

50: Suse Roller

70: drying device

80: winding roller

90: flushing nozzle

J: flushing solution sprayed on aramid fibers

51: flushing liquid jet

52: washing liquid supply pipe

The present invention is useful in a variety of product materials that require high elongation characteristics along with high strength characteristics such as tire cord reinforcement.

Claims (6)

1. Acinamide is composed of an aramid copolymer containing a cyano group (-CN) substituted aromatic group, elongation 4.0 ~ 6.5%, crystallinity 30 ~ 55%, crystal size is 15 ~ 40 ~ (200 pages) Degree copolymerized aramid fibers.
2. The high-strength copolymerized aramid fiber of claim 1, wherein the high-strength copolymerized aramid fiber has a strength of 18 to 30 g / d.
3. The high-strength copolymerized aramid fiber of claim 1, wherein the high-strength copolymerized aramid fiber has a strength of 22 to 28 g / d.
4. The high elongation copolymer aramid fiber according to claim 1, wherein the high elongation copolymer aramid fiber has an elastic modulus of 400 to 600 g / d.
5. The high-strength copolymerized aramid fiber of claim 1, wherein the high-strength copolymerized aramid fiber has a crystal size of 5 to 20 microns (110 planes).
6. The high-strength copolymerized aramid fiber of claim 1, wherein the aramid copolymer film comprising a substituted aromatic group with cyano group (-CN) has a repeating unit of the following general formula (I).

   

   [In Formula (I), Ar is an aromatic group of the following general formula (II), and A is an aromatic group of the following general formula (III) or an aromatic group of the general formula (II) Is an aromatic group having a ratio of 1: 9-9: 1]

   

   

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