JP3911654B2 - Method for producing aramid filaments - Google Patents

Description

実施例８〜１０、比較例３〜４
更に高弾性（９５０ｇ／Ｄ以上）の原糸の実施例を表２に示す。
【００４３】
表２の実施例８〜１０は各々、表１の実施例５、６および７で得られたアラミド長繊維糸を、２９０℃もしくは３００℃の温度で連続的に熱処理したものである。熱処理して得られた原糸物性を表２に示す。
【００４４】
また、比較例３〜４も表２に示す。これは表１の比較例１、２で得られたアラミド長繊維糸を実施例１０と同じ熱処理条件で熱処理したものである。
【００４５】
実施例８〜１０に示すとおり、弾性率は従来の７５０ｇ／Ｄレベルに比べ飛躍的に向上している。
【００４６】
【表２】

なお、製糸された長繊維糸の複数本を合糸することにより、所望の糸条繊度、例えば５０〜１００００Ｄなどとすることができる。
【００４７】
【発明の効果】
本発明で得られるポリ（ｐーフェニレンテレフタラミド）からなるアラミド長繊維糸は、極めて高い強度で、かつ十分な弾性率を有するか、または、極めて高い弾性率で、かつ十分な強度を有するものであるため、従来のポリ（ｐーフェニレンテレフタラミド）からなるアラミド長繊維糸では適用困難であった各種用途に適用可能となる。 [0001]
BACKGROUND OF THE INVENTION
The present invention relates to a method for producing an aramid continuous fiber yarn having high strength and high elastic modulus.
[0002]
[Prior art]
Aramid fibers, particularly para-oriented aramid fibers, have excellent properties such as high strength and high heat resistance, and are therefore widely used in industrial and clothing applications.
[0003]
The basic method for manufacturing a para-aramid fibers are proposed air gap spinning process is in U.S. Patent No. 3,767,756, a liquid crystal aromatic polyamide dissolved in 98 to 100.2% sulfuric acid, A method for obtaining high-strength and high-elasticity aramid fibers in the steps of coagulation, washing with water and drying is described. On the basis of this invention, an attempt to obtain a higher strength yarn has been made, and a higher strength yarn has been obtained.
[0004]
That is, in U.S. Patent No. 3,767,756, polymer viscosity of 4.0 or more, using a solution of aromatic polyamide dissolved in from 98 to 100.2 percent sulfuric acid, spinning, coagulation, washing with water, drying step The washing tension is 1/3 of the drying tension, that is, washing with a tension of 2 g / D or more (D is a single yarn denier measured with a fiber bundle), and drying is performed at a temperature of 300 ° C. or less. . Among them, the drying tension is 3-7 g / D which is much higher than the usual 2.5 g / D or less, and it is shown that higher strength can be obtained by making the moisture at least 10%. Yes.
[0005]
On the other hand, U.S. Patent No. 4726922, water and dried under low tension does not affect the strength of the yarn, and dried under high tension or medium tension, 0.5 g / D or more increase in strength is It is obtained that the elastic modulus is improved. Further, paying attention to the fact that high strength can be obtained even if the drying tension is lowered by increasing the tension of washing and neutralization, the raw yarn strength and elastic modulus are 27.3 g / D and 799 g / in, respectively, in Example I. D, Example II includes 27.4 g / D, 849 g / D, 26.2 g / D, and 900 g / D, and Example III has a strength of 27.8 to 26.4 g / D. There is also a description example of the elastic modulus 869 to 909 g / D.
[0006]
However, these drying tensions, to US Patent No. 3767756 Pat At 3 to 7 g / D, U.S. Patent No. At Pat 4726922 3.7~5.23g / D and less tension normal 1 g / D , It is dried at a tension of 3 to 7 times, and as a commercial production, there is concern about the occurrence of fluff and tarmi, and the deterioration of quality is unavoidable. Is difficult to get. On the other hand, US Patent No. 5173236 low tension (0.05~0.35g / D) washing, with drying, by a combination of the base and the coagulation bath, with the strength of 27.9~26.5g / D However, the elastic modulus is a low level of 470 to 483 g / D.
[0007]
In addition, the 60-52617 discloses and U.S. Patent No. 4,560,743 JP, at low tension drying (0.11~0.45g / D), strong degree 35～40.2G / d, it is described that give the aramid fiber yarns of elastic modulus 540~470g / d. In this method, the strength is extremely high, but the elastic modulus is insufficient.
[0008]
As described above, in the conventional aramid long fiber yarn made of poly (p-phenylene terephthalamide) , the strength of the multifilament yarn does not exceed 28.5 g / D, or the elastic modulus exceeds 950 g / D, and high strength strength is 22 g / D or more, high modulus yarns also have greens.
[0009]
[Problems to be solved by the invention]
The present invention aims to improve the properties of multifilaments that can be applied to commercial production, and has a very high strength and sufficient elastic modulus, or a very high elastic modulus and sufficient strength. it is an object of the present invention to provide a method for manufacturing aramid textiles consisting Terefutaramido).
[0010]
[Means for Solving the Problems]
The present invention as a means for solving the above problems, a poly (p-phenylene terephthalamide) sulfuric acid solution is spun into a coagulation bath through an air gap through an air gap, In a method for producing an aramid long fiber yarn composed of multifilaments through water washing, neutralization, and drying steps, the diameter of the nozzle discharge hole is set to 2.0 mil or less, and the single yarn fineness of the produced long fiber yarn is 0.3 to 1 4d, the ratio of the amount of coagulated liquid per unit time in the coagulation bath to the mass of the passing yarn ( mass ratio) is 250 or more, and the drying tension in the drying step is 2.0 to 2.5 g / D. This is a method for producing an aramid long fiber yarn having a single yarn fineness of 0.3 to 1.4 d, a strength exceeding 28.5 g / D, and an elastic modulus of 700 to 1200 g / D.
Furthermore, a sulfuric acid solution of poly (p-phenylene terephthalamide) is spun into a coagulation bath through an air gap through an air gap, In a method for producing an aramid long fiber yarn composed of multifilaments through water washing, neutralization, and drying steps, the diameter of the nozzle discharge hole is 2.0 mil or less, and the single yarn fineness of the produced long fiber yarn is 0.3 to 1.4d, the ratio of the amount of coagulated liquid per unit time in the coagulation bath to the mass of the passing yarn ( mass ratio) is 250 or more, and the drying tension in the drying step is 2.0 to 2.5 g. / D and a heat treatment temperature of 200 to 300 ° C., the single yarn fineness is 0.3 to 1.4 d, the strength is 22 to 28.5 g / D, and the elastic modulus is 950 to 1200 g / It is a manufacturing method of the aramid long fiber yarn which is D.
[0012]
DETAILED DESCRIPTION OF THE INVENTION
A aramid, the aromatic diamine and an aromatic dicarboxylic acid is a polymer having a structural unit amide bond, the aromatic diamine, p- phenylenediamine, m- phenylenediamine, 4,4'-diaminodiphenyl ether, 3 4,4'-diaminodiphenyl ether or a nucleus-substituted compound thereof, and examples of the dicarboxylic acid include terephthalic acid, isophthalic acid, and 2,6-naphthalenedicarboxylic acid . Of these, a combination of p-phenylenediamine and terephthalic acid is preferable.
[0014]
The present invention method is a homopolymer of para-aromatic polyamide, i.e., by using poly (p over phenylene terephthalamide), represented by U.S. Pat. No. 3,767,765 and 4,965,033 Pat A high tenacity yarn is obtained by an air gap spinning process using liquid crystal, that is, a dry and wet spinning process (liquid crystal spinning process) .
[0015]
That is, as shown in these patents, the basic manufacturing process of para-aromatic polyamide fibers is a method of extruding a polymer sulfuric acid solution (spinning solution) exhibiting liquid crystal properties in an air gap spinning process from a nozzle discharge hole into a fiber form. After that, it is led to the coagulation bath through the air gap. Here, the concentrated sulfuric acid component in the fiber derived from the solvent in the spinning solution moves to dilute sulfuric acid which is a coagulation bath. Thereafter, the fiber is washed, neutralized, dried and wound up, and further heat-treated as necessary. Respect of the coagulation bath techniques are described in U.S. Patent No. 4,965,033.
The method of the present invention is based on the above-described production method , and commercially high quality high strength yarn (strength 28.5 g / D or more, elastic modulus 700 to 1200 g / D) and high elasticity yarn (elasticity) by changing the conditions in each process . rate 950~1200g / D, in which the intensity 22~28.5g / D) was possible to manufacture.
[0016]
Further, in the present invention method, the single yarn fineness of the aramid filament yarn produced (unit: d) is generally to be those thinner than commercially produced Tei Ru aramid filament yarns, more specifically 0.3 and ~1.4d, good Mashiku is the 0.5~1.2d.
[0017]
Yarn fineness of Alami de filament yarn produced in the present invention method is preferably 50～1000D. If a plurality of these long fiber yarns are combined , the yarn fineness can be set to 50 to 10000D . Moreover, this long fiber yarn can also be used by entangled single fibers by a known entanglement method for ordinary fibers.
[0018]
Next, a production method for obtaining the aramid long fiber yarn of the present invention will be described along with a production example of a multifilament yarn made of poly (paraphenylene terephthalamide).
[0019]
Poly (p-phenylene terephthalamide) is dissolved in sulfuric acid so as to be an approximately 19.50% by weight solution, and the solution (spinning solution) is guided to the spinning process at a temperature above the freezing point (approximately 70 ° C.). In this spinning process, the spinning solvent solution for example through a die having a pore size of 2.0 mil, is formed into fibers led in Mareryu acid coagulation bath cold through an air gap (e.g., 3 ° C.), then washed with water, medium After drying through the summing process, the aramid long fiber yarn is wound up.
[0020]
In this dry-wet spinning method, in order to improve the strength and modulus of the aramid filament yarn, fibers oriented to how the liquid crystal domains until entering the coagulation bath from a nozzle, and that either a fixed, each An important point is how to perform uniform solidification for each single yarn.
[0021]
Further, the strength and elastic modulus can be adjusted to some extent by variously changing the tension of the subsequent yarn.
[0022]
In general, para-aramid fibers coagulate the polymer into a fibrous form through a coagulation solution, so a two-layer structure is formed in the inner and outer layers of the fiber. It is important to reduce this two-layer structure as much as possible and increase the surface layer portion. It is.
[0023]
From the above knowledge, the following conditions are required to produce the aramid long fiber yarn of the present invention .
[0024]
That is, to adopt a means for diameter reduction of the discharge holes in order to increase the molecular orientation after ejection from a die sufficiently. Since a normal orientation can not be obtained with a normal discharge hole diameter of 2.5 mil, the discharge hole diameter is set to 2.0 mil or less . Further, the fineness is such that the single yarn fineness is 1.4 d or less . Thus, rapid and is uniformly solidified after discharge, it is Rukoto to high orientation.
[0025]
Further, in order to equalize the coagulating bath spun yarn passes, its coagulating liquid volume and passing yarn mass velocity ratio of the (Mass Ratio) 2 50 or more. Thereby, a sufficiently uniform coagulated yarn can be obtained. This speed ratio (Mass Ratio) are described in U.S. Patent No. 4,965,033.
[0026]
As a method for contacting the coagulating solution and spun yarn, passes the spun yarn into the hole of the coagulation bath funneled tray hole is opened in the center, the tray system for pouring coagulating liquid at the same time to the spun yarn It is preferable to combine a jet system in which a jet of coagulating liquid is injected.
[0027]
In the case of adopting the jet method, the ratio (Flow Ratio) between the jet speed of the coagulation liquid and the yarn speed of the spun yarn is preferably 1.0 to 1.5. By maintaining this range, a high-strength yarn with no slack can be obtained.
[0028]
It is preferable to maintain the ratio of spinning speed / die discharge linear speed at 1.0 to 7.0. 1 to 2.0 is preferred, which is preferred for the prevention of adhesions between yarn breakage and single yarn.
[0029]
Further, when the spinning speed is too slow to occur decrease the viscosity of the polymer, if too fast tend to not be obtained high tenacity yarn becomes high tension immediately after spinning. Therefore, it is desirable to optimize the spinning speed in accordance with the fineness .
[0030]
Furthermore, the tension applied to washing, neutralization and drying after spinning also affects the single yarn strength, and the stretch ratio between the feed roll and the drying roll is preferably 1.1 to 1.5. Since the present invention method is aimed sufficiently high orientation by the fineness slender, dry tension of 3 to 7 g / d, as shown in U.S. Patent No. 4,726,922 high tension forces required Ku, a dry tension of 2.0~2.5g / D.
[0031]
The aramid long fiber yarn obtained under the above conditions has extremely high strength and sufficient elastic modulus . By heat-treating this, the elastic modulus can be further improved. However, the strength slightly decreases at that time.
[0032]
Heat treatment conditions in this U.S. Pat. No. 4,726,922 Pat has been that way 200 ° C. or higher according to, to 300 ° C. or lower. Preferably, the temperature is 230 ° C to 300 ° C.
[0033]
By selecting each of these yarn making conditions, the high strength yarn and the high elastic yarn of the present invention can be obtained.
[0034]
The aramid long fiber yarn of the present invention can be processed in the same manner as a conventional aramid long fiber yarn, and can be made into various processed products.
[0035]
Moreover, these processed goods can be made into an aramid fiber reinforced material by disposing in a matrix. As the matrix, natural rubber, synthetic rubber, polyamide resin, polyester resin, polyolefin resin, polyvinyl chloride resin, PBT resin, PPS resin, PPO resin, ABS resin and other thermoplastic resins, epoxy resin, phenol resin, melamine resin, Examples thereof include thermosetting resins such as unsaturated polyester resins, and inorganic matrices such as mortar and cement.
[0036]
Examples of the method of disposing in the matrix include a method of kneading single fibers in the matrix, a method of impregnating the fiber yarn with the matrix, a method of impregnating the fiber fabric with the matrix, and the like.
[0037]
Further, the aramid long fiber yarn of the present invention can be directly supplied with the processed product or twisted yarn form or the raw yarn as described above, such as various industrial materials such as belts, tire cords, optical fiber tension members, bulletproof devices, building materials, reinforcing materials, etc. It can be used for clothing such as industrial materials, fireproof clothing and gloves.
[0038]
【Example】
Hereinafter, the present invention will be described by way of specific examples.
[0039]
Examples 1-7
Poly (p-phenylene terephthalamide) was dissolved in sulfuric acid to obtain a solution having a polymer concentration of 19.50% by weight , and the solution was introduced into the spinning process at 70 ° C. The coagulation liquid after passing through the air gap, using a dilute sulfuric acid of 3 ° C., in combination with the tray system and jet system in contact with the coagulating liquid and the spun yarn. After spinning out coagulation bath of yarn passage, washed with water, alkali washing, to produce aramid filament yarn through a drying step. The strength, elastic modulus, and elongation of the obtained long fiber yarn were measured, and the results are shown in Table 1. Table 1 also shows the yarn production conditions.
[0040]
As shown in Examples 1 to 7 in Table 1, high-performance raw yarns having a strength of 28.5 g / D or more and an elastic modulus of 700 g / D or more were obtained.
[0041]
Comparative Examples 1-2
Aramid long fiber yarns were produced by changing the spinning conditions to the known conditions shown in Table 1 with the same polymer and the same spinning process as in the examples . The obtained raw yarn physical properties are summarized in Table 1. Long fiber yarn obtained in Comparative Examples 1 and 2 compared with the present invention, were inferior in the strength of and elastic modulus.
[0042]
[Table 1]

Examples 8-10, Comparative Examples 3-4
Table 2 shows examples of yarns having higher elasticity (950 g / D or more).
[0043]
The examples in Table 2 8-10 respectively, in which the aramid filament yarns obtained in Examples 5, 6 and 7 of Table 1 was continuously heat-treated at a temperature of 290 ° C. or 300 ° C.. Table 2 shows the properties of the raw yarn obtained by the heat treatment .
[0044]
Comparative examples 3 to 4 are also shown in Table 2. This is obtained by heat treatment with the same heat treatment conditions as aramid filament yarns Example 10 obtained in Comparative Examples 1 and 2 of Table 1.
[0045]
As shown in Examples 8 to 10, the elastic modulus is dramatically improved compared to the conventional 750 g / D level.
[0046]
[Table 2]

Note that by doubling a plurality of the long fiber yarn which is reeling, Ru can be, eg desired yarn fineness, for example 50～10000D.
[0047]
【The invention's effect】
The aramid long fiber yarn made of poly (p-phenylene terephthalamide) obtained in the present invention has a very high strength and a sufficient elastic modulus, or has a very high elastic modulus and a sufficient strength. for those, the applicable available-for application which was difficult various applications in aramid filament yarns made of conventional poly (p over phenylene terephthalamide).

Claims (7)

In a method for producing an aramid long fiber yarn composed of multifilaments, a poly (p-phenylene terephthalamide) sulfuric acid solution is spun into a coagulation bath through an air gap through a die, washed with water, neutralized, and dried. The diameter of the nozzle discharge hole is set to 2.0 mil or less, the single yarn fineness of the produced long fiber yarn is 0.3 to 1.4 d, and the ratio of the amount of coagulated liquid per unit time in the coagulation bath to the mass of the passing yarn ( When the mass ratio is 250 or more and the drying tension in the drying step is 2.0 to 2.5 g / D , the single yarn fineness is 0.3 to 1.4 d and the strength is 28.5 g / D. And a method for producing an aramid continuous fiber yarn having an elastic modulus of 700 to 1200 g / D. A poly (p-phenylene terephthalamide) sulfuric acid solution is spun into a coagulation bath through an air gap through a die, washed, neutralized, dried, then heat treated to produce multifilament aramid long fiber yarns. In the manufacturing method, the diameter of the nozzle discharge hole is set to 2.0 mil or less, the single yarn fineness of the manufactured long fiber yarn is set to 0.3 to 1.4 d, and the amount of coagulation liquid per unit time and passage in the coagulation bath When the yarn mass ratio is 250 or more, the drying tension in the drying step is 2.0 to 2.5 g / D, and the heat treatment temperature is 200 to 300 ° C., the single yarn fineness is 0. A method for producing an aramid continuous fiber yarn having a strength of 22 to 28.5 g / D and an elastic modulus of 950 to 1200 g / D, 3 to 1.4 d . The method for producing an aramid continuous fiber yarn according to claim 1 or 2, wherein the elongation at break is 2.0 to 4.5% . The method for producing an aramid long fiber yarn according to any one of claims 1 to 3, wherein the filament fineness of the long fiber yarn is 50 to 10,000 D. The method for producing an aramid continuous fiber yarn according to claim 4, wherein the single fibers are entangled with each other . An aramid fiber processed product obtained by processing an aramid long fiber yarn obtained by the production method according to claim 1.   An aramid fiber reinforced product in which the processed aramid fiber product according to claim 6 is disposed in a matrix.