KR20170017829A - Copolynerized aramid fiber with high elasticity - Google Patents

Abstract

Copolymerized aramid fiber with high elongation 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 15-40 (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 high strength properties as an intrinsic characteristic of an aramid fiber. The present invention is useful as a material for various products requiring high strength properties of the aramid fiber as well as high elongation properties at the same time.

Description

[0001] Copolynerized aramid fiber with high elasticity [0002]

More specifically, the present invention relates to a high-co-polymerized aramid fiber comprising an aramid copolymer containing an aromatic group substituted with a cyano group (-CN), having a loose fiber structure and a reduced crystallinity and crystal size, The present invention relates to a copolymerized aramid fiber.

The 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-tonne automobile by a thin thread having a thickness of about 5 mm, It has been used in a variety of applications in high-tech industries such as aerospace.

The aramid fibers are typically produced by a process comprising the steps of (i) spinning an aramid yarn dope through a spinneret 20, and (ii) spinning the aramid fibers into a coagulation bath 30 and (Iii) a step of passing the coagulated aramid fibers through the at least one wash rollers 50 in order as shown in FIG. 4, while passing through the coagulation tubes 40, (Iv) a step of drying the washed aramid fibers with a drying device (70), and then winding the washed aramid fibers on the aramid fibers passing through the water washing rollers (50) And winding them around the rollers 80 in that order.

For example, as disclosed in Korean Patent No. 10-0910537, an aromatic diamine such as paraphenylenediamine is dissolved in an organic solvent to which an inorganic salt is added to prepare an aramid radiation dope, A solution is prepared, and an aromatic diacid halide such as terephthaloyl dichloride or the like is added to the mixed solution. To prepare an aramid polymer, and then the prepared aramid polymer was dissolved in sulfuric acid to prepare a radiation dope.

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

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

The aromatic diacid halide may be terephthaloyl dichloride, 4,4'-benzoyl dichloride, 2,6-naphthalene dicarboxylic acid dichloride, or 1,5-naphthalene dicarboxylic acid dichloride.

The aramid polymer may be selected from the group consisting of polyparaphenylene terephthalamide, poly (4,4'-benzanilide terephthalamide), poly (paraphenylene-4,4'-bis Phenylene-dicarboxylic acid amide), or poly (paraphenylene-2,6-naphthalene dicarboxylic acid amide).

As an example of another method of producing the aramid radiation dope, there is disclosed an organic solvent in which paraphenylenediamine and cyano-para-phenylenediamine are dissolved in an organic solvent as disclosed in Korean Patent No. 10-171994 Terephthaloyldichloride was added and reacted to prepare a radiation dope containing a copolymerized aramid polymer containing an aromatic group substituted with a cyano group (-CN). In this case, the copolymerized aramid polymer can be advantageously prepared as a radiation dope without a process of dissolving the copolymerized aramid polymer in sulfuric acid.

Conventional aramid fibers produced by the methods described above are dense and have a low degree of crystallinity and crystal size because they have a low fiber elongation of less than 4%. Therefore, aramid fibers produced by the above-described methods are required to have high intrinsic strength and high- There were limitations that were difficult to use.

The object of the present invention is to provide a high-grade aramid-coated aramid fiber having an elongation of 4.0 to 6.5%, which is made of an aramid copolymer containing an aromatic group substituted with cyano group (-CN).

In order to achieve the above object, the present invention rapidly extracts the organic solvent remaining in the aramid fibers in the coagulation process and the washing process for producing the aramid fibers, thereby reducing the crystallinity and crystal size of the aramid fibers and loosening the structure of the aramid fibers It increases the shinto.

The present invention relates to an aramid fiber comprising an aramid copolymer containing an aromatic group substituted with a cyano group (-CN), having a loose fiber structure, a small degree of crystallinity and a small crystal size, .

INDUSTRIAL APPLICABILITY The present invention is useful as a material for various products requiring high strength properties as well as high strength properties of aramid fibers.

BRIEF DESCRIPTION OF THE DRAWINGS Figure 1 is a schematic view of a process for producing aramid fibers.
2 is a cross-sectional view of a water wash roller used in an embodiment of the present invention.
3 is a schematic view of the process of washing the aramid fibers using the water wash roller of FIG. 2 in the present invention.
4 is a schematic view of a process for washing aramid fibers by a conventional method.

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

The high-tin-copolymerized aramid fiber according to the present invention comprises an aramid copolymer containing an aromatic group substituted with a cyano group (-CN), having an elongation of 4.0 to 6.5%, a crystallinity of 30 to 55%, a crystal size of 15 to 40 Å (200 sides).

The present invention relates to a thermoplastic resin composition comprising an aramid copolymer containing an aromatic group substituted with a cyano group (-CN), having an elongation of 4.0 to 6.5%, a crystallinity of 30 to 55%, a crystal size of 15 to 40 Å (200 plane) Of 18 to 25 g / d.

The present invention relates to a thermoplastic resin composition comprising an aramid copolymer containing an aromatic group substituted with a cyano group (-CN), having an elongation of 4.0 to 6.5%, a crystallinity of 30 to 55%, a crystal size of 15 to 40 Å (200 plane) Dyed aramid fibers of 400 to 600 g / d.

The present invention relates to a process for producing an aromatic polyamide which comprises an aramid copolymer containing an aromatic group substituted with a cyano group (-CN), having an elongation of 4.0 to 6.5%, a crystallinity of 30 to 55%, a crystal size of 15 to 40 Å (200 plane) And a high-co-polymerized aramid fiber of 20 Å (110 sides).

The aramid copolymer containing an aromatic group substituted with a cyano group (-CN) has a repeating unit represented by the following general formula (I).

Wherein Ar is an aromatic group represented by the following general formula (II), A is an aromatic group represented by the following general formula (III), or an aromatic group represented by the following general formula (II) and an aromatic group represented by the general formula (III) Aromatic group having a ratio of 1: 9 to 9: 1]

Various properties of the high-tin-copolymerized aramid fiber according to the present invention were evaluated by the following methods.

Crystallinity ( % )

The diffraction pattern obtained by X-ray analysis was used to determine the ratio of the gait peak to the amorphous peak.

Crystal size (A)

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

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

The tensile properties of the aramid fibers were measured according to the ASTM D885 test method. Specifically, the physical properties of the fibers were determined by stretching until the copolymerized aramid fibers having a length of 25 cm were broken in an Instron Tester (Instron Engineering Corp., Canton, Mass).

At this time, the tensile speed was set at 300 mm / min, and the initial load was set at a fineness of 1/30 g. The number of samples was determined by the average value after testing five samples. The modulus of elasticity was calculated from the slope of the S-S curve, the maximum strength at break, and the elongation at break.

Next, an example of a method for producing the high-crystallinity aramid fiber of the present invention will be described.

An example of the following production method is merely an example of producing the high-cinnamon-copolymerized aramid fiber of the present invention and should not be construed as limiting the protection scope of the present invention.

First, the present invention carries out a step of manufacturing a radiation dope for producing aramid fibers. Specifically, after an inorganic salt is added to an organic solvent to prepare a polymerization solvent, paraphenylenediamine and cyano-para-phenylenediamine are dissolved together in the organic solvent, or cyano-para- To prepare a mixed solution. Thereafter, a small amount of terephthaloyldichloride is added to the mixed solution while stirring the mixed solution to perform a primary polymerization to form a prepolymer in the polymerization solvent.

Next, terephthaloyldichloride is further added to the polymerization solvent to perform secondary polymerization, and a radial dope for preparing aramid in which a copolymerized aramid copolymer containing an aromatic group substituted with cyano group (-CN) is dissolved in an organic solvent .

N, N'-dimethylacetamide (DMAc), hexamethylphosphoramide (HMPA), N, N, N ', N', N'- -Tetramethylurea (TMU), N, N-dimethylformamide (DMF) or mixtures thereof may be used. The inorganic salt may be used a mixture of _{CaCl 2, LiCl, NaCl, KCl} , LiBr, KBr, or mixtures thereof.

Next, as shown in FIG. 1, after the radiation dope produced as described above is radiated through the spinneret 20, the radiated aramid fiber is sprayed onto the coagulation bath 30 and the coagulating solution And then the coagulated aramid fibers are washed with water while sequentially passing over the water wash rollers 50 and 60. Thereafter, the dried aramid fibers are wound on a winding roller 80 after being dried by a drying device 70, Aramid fibers.

At this time, in an embodiment of the present invention, (i) water (pure water) at 20 to 60 ° C is used as the coagulating solution, (ii) water (pure water) at 30 to 70 ° C is used as the washing liquid for the washing step (Iii) As shown in FIG. 2, on the surface, a water-washing liquid injection opening 51 for spraying a washing liquid by a centrifugal force generated by the rotation of the water washing roller 50 is formed. Inside the water washing roller 50 A water washing liquid supply pipe 52 concentric with the outer circumferential circle of the water wash roller 50 and hollow is formed and the water washing liquid injection openings 51 are connected to the water wash rollers 52 communicated with the water washing liquid supply pipe 52 50) is used to rapidly extract the organic solvent remaining in the aramid fiber (Y).

3, when the aramid fibers Y pass over the water wash rollers 50, the wash water contained in the wash water supply pipe 52 formed inside the water wash rollers 50 passes through the water wash rollers 50, Is injected in the direction of the aramid fiber (Y) through the water-washing liquid injecting opening (51) formed on the surface of the water washing roller (50) by the centrifugal force generated by the rotation of the water washing roller

As a result, the injected washing liquid can be smoothly penetrated into the aramid yarn Y passing through the water wash rollers 50, so that the organic solvent remaining in the aramid fibers Y can be extracted quickly.

If the organic solvent remaining in the aramid fiber (Y) is rapidly extracted, the structure of the fiber is loosened, the crystallinity and the crystal size are reduced, and the elongation of the fiber is greatly improved.

Further, in the embodiment of the present invention, water (pure water) that maintains a temperature of room temperature or more is used as the coagulating liquid and the washing liquid, so that the organic solvent remaining in the aramid fiber (Y) can be extracted quickly.

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

However, the following embodiments are merely preferred embodiments of the present invention, and should not be construed as limiting the scope of protection 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 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 to prepare a radiation dope containing the copolymerized aramid polymer.

1, the radiated dope is radiated through a spinneret 20, and the radiated copolymerized aramid fibers are irradiated with a coagulation bath 30 containing 40 ° C of water (coagulation liquid) (Coagulation solution) is injected into the coagulation tube 40 through which the water (coagulation solution) is injected, and then the coagulated aramid fiber that has passed through the coagulation tube 40 is continuously applied to the surface of the water retention roller 50 And a water-washing liquid injecting port 51 for injecting washing liquid is formed by a centrifugal force generated by the rotation of the water-washing roller 50. In the water-washing roller 50, a water bath liquid concentric with the outer circumferential circle of the water- And the jetting ports 51 are passed through the water wash rollers 50 communicating with the water washing liquid supply pipe 52 and are connected to the water washing liquid supply pipe 52 formed inside the water washing roller 50 The wash water, which is the water at 50 ° C, A step of spraying the water onto the co-aramid fibers passing over the water wash rollers 50 through the water washing liquid injection openings 51 formed on the surface of the water wash rollers 50 by the centrifugal force generated by the rotation of the roller 50 is referred to as 2 Then, the coated aramid fiber was dried by a drying device 70 and wound up on a winding roller 80 to produce a co-aramid fiber. The results of evaluating various physical properties of the produced copolymerized aramid fiber are 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 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 to prepare a radiation dope containing the copolymerized aramid polymer.

1, the radiation dope is radiated through a spinneret 20, and the radiated copolymerized aramid fibers are irradiated with a coagulation bath 30 containing 50 ° C water (coagulation liquid) (Coagulation solution) is injected into the coagulation tube 40 through which the water (coagulation solution) is injected, and then the coagulated aramid fiber that has passed through the coagulation tube 40 is continuously applied to the surface of the water retention roller 50 And a water-washing liquid injecting port 51 for injecting washing liquid is formed by a centrifugal force generated by the rotation of the water-washing roller 50. In the water-washing roller 50, a water bath liquid concentric with the outer circumferential circle of the water- And the jetting ports 51 are passed through the water wash rollers 50 communicating with the water washing liquid supply pipe 52 and are connected to the water washing liquid supply pipe 52 formed inside the water washing roller 50 The water solution, which is the water at 60 ° C, A step of spraying the water onto the co-aramid fibers passing over the water wash rollers 50 through the water washing liquid injection openings 51 formed on the surface of the water wash rollers 50 by the centrifugal force generated by the rotation of the roller 50 is referred to as 2 Then, the coated aramid fiber was dried by a drying device 70 and wound up on a winding roller 80 to produce a co-aramid fiber. The results of evaluating various physical properties of the produced copolymerized aramid fiber are 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 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 to prepare a radiation dope containing the copolymerized aramid polymer.

1, the radiated dope is radiated through a spinneret 20, and the radiated copolymerized aramid fibers are irradiated with a coagulation bath 30 containing 40 ° C of water (coagulation liquid) (Coagulation solution) is injected into the coagulation tube 40 through which the water (coagulation solution) is injected, and then the coagulated aramid fiber that has passed through the coagulation tube 40 is continuously applied to the surface of the water retention roller 50 And a water-washing liquid injecting port 51 for injecting washing liquid is formed by a centrifugal force generated by the rotation of the water-washing roller 50. In the water-washing roller 50, a water bath liquid concentric with the outer circumferential circle of the water- And the jetting ports 51 are passed through the water wash rollers 50 communicating with the water washing liquid supply pipe 52 and are connected to the water washing liquid supply pipe 52 formed inside the water washing roller 50 The wash water, which is the water at 50 ° C, A step of spraying and washing the co-aramid fibers passing over the water wash rollers 50 through the water washing liquid injection port 51 formed on the surface of the water wash roller 50 by the centrifugal force generated by the rotation of the roller 50 is referred to as 3 Then, the coated aramid fiber was dried by a drying device 70 and wound up on a winding roller 80 to produce a co-aramid fiber. The results of evaluating various physical properties of the produced copolymerized aramid fiber are 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 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 to prepare a radiation dope containing the copolymerized aramid polymer.

1, the radiated dope is radiated through a spinneret 20, and the radiated copolymerized aramid fibers are irradiated with a coagulation bath 30 containing 40 ° C of water (coagulation liquid) (Coagulation solution) is injected into the coagulation tube 40 through which the water (coagulation solution) is injected, and then the coagulated aramid fiber that has passed through the coagulation tube 40 is continuously applied to the surface of the water retention roller 50 And a water-washing liquid injecting port 51 for injecting washing liquid is formed by a centrifugal force generated by the rotation of the water-washing roller 50. In the water-washing roller 50, a water bath liquid concentric with the outer circumferential circle of the water- And the jetting ports 51 are passed through the water wash rollers 50 communicating with the water washing liquid supply pipe 52 and are connected to the water washing liquid supply pipe 52 formed inside the water washing roller 50 The wash water, which is the water at 50 ° C, A step of spraying and washing the co-aramid fibers passing over the water wash rollers 50 through the water washing liquid injection port 51 formed on the surface of the water wash roller 50 by the centrifugal force generated by the rotation of the roller 50 is referred to as 3 Then, the coated aramid fiber was dried by a drying device 70 and wound up on a winding roller 80 to produce a co-aramid fiber. The results of evaluating various physical properties of the produced copolymerized aramid fiber are 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 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 to prepare a radiation dope containing the copolymerized aramid polymer.

1, the radiation dope is radiated through a spinneret 20, and the radiated copolymerized aramid fiber is irradiated with a 10% aqueous solution of N-methyl-2-pyrrolidone (NMP) (Coagulation liquid) is injected into the coagulation tube 40 through which the coagulation bath 30 and the 10% N-methyl-2-pyrrolidone (NMP) 4, the water solution, which is water at 15 ° C, is supplied to the water wash rollers 50 through the wash water spray nozzles 90 at the upper end of the water wash rollers 50 ), And washed with water, followed by drying with a drying device (70), and wound around a winding roller (80) to prepare a co-aramid fiber. The results of evaluating various physical properties of the produced copolymerized aramid fiber are 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 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 to prepare a radiation dope containing the copolymerized aramid polymer.

1, the radiation dope is radiated through a spinneret 20, and the radiated copolymerized aramid fiber is irradiated with a 10% aqueous solution of N-methyl-2-pyrrolidone (NMP) (Coagulation liquid) is injected into the coagulation tube 40 through which the coagulation bath 30 and the 10% N-methyl-2-pyrrolidone (NMP) 4, the water solution, which is water at 15 ° C, is supplied to the water wash rollers 50 through the wash water spray nozzles 90 at the upper end of the water wash rollers 50 ), And washed with water, followed by drying with a drying device (70), and wound around a winding roller (80) to prepare a co-aramid fiber. The results of evaluating various physical properties of the produced copolymerized aramid fiber are shown in Table 1.

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

10: Extruder
20: spinning detention
30: Coagulation bath
40: Coagulation tube
41:
Y: Aramid fiber
50: Wash rollers
70: Drying device
80: Winding roller
90: Wash liquid spray nozzle
J: Water solution sprayed on aramid fiber
51: Water liquid injection nozzle
52:

Claims (6)

Wherein the crystallinity is in the range of 4.0 to 6.5%, the crystallinity is in the range of 30 to 55%, and the crystal size is in the range of 15 to 40 ANGSTROM (200 plane), which is composed of an aramid copolymer containing an aromatic group substituted with a cyano group (-CN) Copolymerized aramid fiber. The aramid fiber according to claim 1, wherein the high-tin-copolymerized aramid fiber has a strength of 18 to 30 g / d. The aramid fiber according to claim 1, wherein the high-tin-copolymerized aramid fiber has a strength of 22 to 28 g / d. The aramid fiber according to claim 1, wherein the high-tin-copolymerized aramid fiber has a modulus of elasticity of 400 to 600 g / d. The aramid fiber according to claim 1, wherein the high-tin-copolymerized aramid fiber has a crystal size of 5 to 20 Å (110). The aramid fiber according to claim 1, wherein the aramid copolymer film having a cyano group (-CN) -substituted aromatic group has a repeating unit represented by the following formula (I).

Wherein Ar is an aromatic group represented by the following general formula (II), A is an aromatic group represented by the following general formula (III), or an aromatic group represented by the following general formula (II) and an aromatic group represented by the general formula (III) Aromatic group having a ratio of 1: 9 to 9: 1]

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