CN1205365C - Poly(p-phenylene terephthalamide) fiber and manufacturing method thereof - Google Patents

Abstract

The invention provides a dyeable polyparaphenylene terephthalamide fiber and a method for producing the same, characterized in that the polyparaphenylene terephthalamide fiber after spinning and once wound before dyeing has a tensile strength of 15 g/denier or more, a crystal size (110 direction) of 30 to 55 AA, and a moisture content before drying of less than 8%. To provide a poly (p-phenylene terephthalamide) fiber which can be dyed while retaining high strength and high elastic modulus and can give a fiber product dyed in various colors.

Description

Poly(p-phenylene terephthalamide) fiber and manufacturing method thereof

technical field

The invention relates to a para-position polyaramid fiber maintaining high strength and high elastic modulus and a manufacturing method thereof.

Background technique

Polyparaphenylene terephthalamide fibers (hereinafter referred to as para-type polyaramid fibers) have excellent properties such as high strength, high elastic modulus, high heat resistance, non-conductivity and rust resistance, and A synthetic fiber with excellent properties such as softness and light weight unique to organic fibers. Due to these characteristics, it can be used as a reinforcing material for automobile, motorcycle and bicycle tires, gear belts for automobiles, and conveyor belts. Moreover, it can also be used for reinforcement and rope of fiber optic cables. It can also be used as bullet-proof vests, safety gloves with the property of preventing cutting by sharp tools, protective clothing materials such as work clothes, and fire-fighting clothing using its flame-retardant properties.

When used in these fields, in addition to the above properties, dyeability is also required. However, because polyaramid fibers have high crystallinity, strong intermolecular bonding, and compact structure, dyeing is difficult.

Heretofore, the following method has been proposed as a method for dyeing polyaramid fibers.

In JP-A No. 50-12322, the method proposed is a method of diffusing additives such as dyes, antioxidants, ultraviolet shielding agents, and flame retardants in water-swellable fibers. However, Japanese Patent Application Laid-Open No. 50-12322 does not refer to the diffusion of all kinds of dyes in fibers, nor does it describe the conditions. In particular, dyeing with a water content below 50% is not stated.

Japanese Unexamined Patent Publication No. 54-59476 discloses a method in which curls are formed at 10 or more places per inch and dyed from the buckled parts. In addition, JP-A-2-41414 discloses a method of adding an organic dye to a spinning dope. In addition, JP-A-63-145412 discloses a method in which para-oriented polyaramid is introduced into a tension relaxation step when coagulated immediately after spinning, and then brought into contact with a dyeing solution. Moreover, a method proposed in JP-A-7-258980 is to contact the para-type polyarylamide with an intrinsic viscosity less than 2.5dl/g in the state of swelling it with water, and contact it with the dye solution. method. The method proposed in the Japanese Patent Laid-Open No. 8-260362 is to use a fiber swelling agent and use a cationic dye to dye at a temperature above 130°C. The method disclosed in Japanese Unexamined Patent Publication No. 5-209372 is a method for dyeing copolymerized para-type aramid fibers at a temperature above 160°C by using disperse dyes with a molecular weight of 400 or less. In addition, the method proposed in JP-A-9-87978 and JP-A-9-87979 is a method of high-pressure dyeing at 200°C after treating the para-type polyaramid fiber with a polar solution such as dimethyl sulfoxide. .

However, the method described in JP-A-54-59476 is industrially difficult to achieve a crimp of 10 crimps/inch or more for high-strength rigid para-aramid fibers, and is limited to the production of short fibers. The method proposed in JP-2-41414 is the so-called original color spinning method, while the method recorded in JP-63-145412 is to contact with the dye solution under tension-free conditions without immediately winding once after spinning. Methods. In any method, hues are limited with the production volume of each color as a prerequisite. In the method described in JP-A-7-258980, since the viscosity of the polymer is low, the strength of the fiber is extremely low, and it does not have the feature of polyaramid fiber which is a high-strength fiber. The method described in Japanese Patent Application Publication No. 8-260362 relates to the scheme of using a short-fiber yarn whose tensile strength and tensile elastic modulus are all worse than that of the filament yarn. Therefore, the original high strength and high The filament yarn dyeing method of elastic modulus function cannot be used. The methods described in JP-A-5-209372, JP-A-9-87978 and JP-A-9-87979 require special equipment such as a polar solution recovery device and high-temperature dyeing, and therefore are not common methods.

Previously, in the form of filament yarns with high strength and high elastic modulus, which are characteristic of polyaramid fibers, post-dyeing in various colors can be used, that is, filament yarns are wound on tubular objects after spinning On the other hand, after the process is stopped, the cut parts are moved to the dyeing process, and the method of dyeing each color and carrying out multiple colors has not been realized so far.

Generally speaking, the yarn making process of forming filament yarn fibers and the dyeing process of dyeing fibers are separated from each other, and can be implemented by various special equipment and specialized technicians. In order to meet customers' strict requirements on the color of dyed fiber products, it is of great significance to stop the process once after the fiber is produced, and transport the fiber to the dyeing factory for dyeing by specialized dyeing technicians to the color tone required by customers.

disclosure of invention

The object of the present invention is to provide a para-position polyaramid fiber that can be dyed with high strength and high modulus of elasticity, and a para-position polyaramid fiber that can be dyed into various shades.

In order to achieve the above objects, the present invention employs the following means.

(1) A polyparaphenylene terephthalamide fiber that can be dyed is characterized in that, after spinning, the polyparaphenylene terephthalamide fiber before the dyeing of a winding, its stretching The strength reaches 15 g/denier or more, the crystal size (110 direction) reaches 30-55 Å, and there is no history of drying with a moisture content below 8%.

(2) The dyeable poly-p-phenylene terephthalamide fiber described in (1) above, which has no history of drying at a water content of 15% or less.

(3) The fibers described in (1) or (2) above are dyeable poly-p-phenylene terephthalamide short fibers having crimps of 4 to 9 rolls/25 mm and cut into 20 to 150 mm fiber length.

(4) The fibers described in (1) or (2) above are cut into flocculent p-phenylene terephthalamide fibers with a length of 0.1 to 3 mm.

(5) A dyed poly-p-phenylene terephthalamide fiber obtained by dyeing the fiber described in (1) or (2) above.

(6) The dyed poly-p-phenylene terephthalamide fiber described in (5) above, which is dyed with a cationic dye.

(7) A dyed short-fibrous poly-p-phenylene terephthalamide fiber obtained by dyeing the short-fibrous poly-p-phenylene terephthalamide fiber described in (3) above.

(8) The dyed short-fibrous poly-p-phenylene terephthalamide fiber described in (7) above, which is dyed with a cationic dye.

(9) A flocculent dyed poly-p-phenylene terephthalamide fiber obtained by dyeing the flocculent poly-p-phenylene terephthalamide fiber described in (4) above.

(10) The poly-p-phenylene terephthalamide fiber dyed in flocculent form as described in (9) above, which is dyed with a cationic dye.

(11) A kind of manufacture method of the poly-p-phenylene terephthalamide fiber that can be dyed, it is characterized in that, comprise a filament yarn forming process and a process of dyeing the yarn filament yarn, the two processes are Independently, the filament yarn forming process is to make a spinning stock solution with poly-p-phenylene terephthalamide with an intrinsic viscosity (ηinh) of 5 or more, and concentrated sulfuric acid, and pass the spinning stock solution through the fine spinning nozzle. The hole is sprayed into the air once, and immediately introduced into the water to make it solidify, forming a high-strength, high-elastic-modulus filament yarn, and the filament yarn dyeing process is carried out in discontinuous processes, and the obtained fiber tensile strength It reaches above 15g/denier, the crystal size (110 direction) reaches 30-55 Å, and the moisture content of the fiber is generally kept above 8%.

(12) The poly-p-phenylene terephthalamide fiber that can be dyed by the method described in the above (11) is under the condition of the twist number represented by the following formula with a twist coefficient of 0.2 or less, using cationic Dye made by dyeing cheese.

$\mathrm{<span\; class="notranslate">\; K</span>}<span\; class="notranslate">\; =</span><span\; class="notranslate">\; (</span>\mathrm{<span\; class="notranslate">\; T</span>}\sqrt{\mathrm{<span\; class="notranslate">\; D.</span>}}<span\; class="notranslate">\; )</span><span\; class="notranslate">\; /</span>\mathrm{<span\; class="notranslate">\; 2870</span>}$

K: Twist coefficient

T: number of twists (times/m)

D: Denier when absolutely dry (denier)

Implement the scheme of the present invention

The so-called poly-p-phenylene terephthalamide (hereinafter also referred to as PPTA for short) of the present invention is a polymer formed by polycondensation of terephthalic acid and p-phenylenediamine, but it can also be made by using a small amount of dicarboxylic acid and Copolymers of diamines. The poly-p-phenylene terephthalamide fiber of the present invention (hereinafter referred to as the para-type polyaramid fiber) is to make PPTA and concentrated sulfuric acid with an intrinsic viscosity (ηinh) of 5 or more into an optically anisotropic spinning The stock solution, and then the spinning stock solution is sprayed in the air once through the fine holes of the spinning nozzle, immediately introduced into water to solidify, and then led to the Nelson drum, neutralized with sodium hydroxide aqueous solution, sent to the washing process, and heated The drum is slightly dried and passed through a continuous process of winding the filament yarn onto a tube. The twisted para-aramid fiber is packed with polyethylene film as packaging material to prevent drying before sending it to the dyeing process. At this time, the crystallinity of the para-type aramid fiber is 50% or less. At this stage, the tensile elastic modulus of the fiber exceeds 400g/denier, and it has the properties of a high elastic modulus yarn. However, in order to further increase the elastic modulus, heat treatment at 350-400°C for 5-10 seconds after drying, With this treatment, the degree of crystallinity usually exceeds 50%.

The intrinsic viscosity (ηinh) of PPTA used in the present invention is desired to be 5 or more. If the intrinsic viscosity (?inh) is less than 5, it is difficult to obtain high-strength, high-elastic-modulus fiber physical properties.

The para-type aramid fiber of the present invention must have a crystal size (110 direction) of 30-55 Å, and the moisture content is generally above 8%. When the crystal size is less than 30 Å, it is difficult to sufficiently dense the fiber, and the fiber physical properties of high strength and high elastic modulus cannot be obtained. In addition, when it exceeds 55 Å, dyeing is difficult.

The so-called moisture content here is generally above 8%, which means that there is no drying process with a moisture content below 8%. When the moisture content is dried below 8%, the structure becomes dense and dyeing is difficult. Even if water is given again, its dyeing performance cannot be restored. Ideally, the moisture content of the para-polyaramid fibers is expected to be between 15% and 49%. When the moisture content is more than 50%, the frictional resistance against the guide rollers etc. increases, making winding difficult. In order to control such moisture content, it is preferable to dry the spun para-aramid fiber at a heating drum temperature of 100-150° C. for 5-20 seconds. When the drying temperature is lower than 100°C, moisture is difficult to remove, and handling after winding on a tube causes problems. If it exceeds 150°C, crystallization is promoted and dyeing becomes difficult.

In the present invention, para-type aramid fibers having such physical properties are dyed. The dyeing method does not require special equipment or a special method, and existing synthetic fiber dyeing equipment can be used. Add appropriate amount of dyes and auxiliaries and add acid to adjust the pH, for example, start dyeing at 60°C, take 60 minutes to heat up to 130°C and dye for 30 minutes, it can be achieved. When the moisture content is less than 50%, it is best to use cationic dyes that tend to saturate dense structures.

The para-polyaramid fiber of the present invention has many uses. The dyed para polyaramid fiber filament yarn can be used as cotton thread, cord, rope and fabric for sewing machines of various colors. The para-polyaramid fiber fabrics with various colors obtained according to the present invention can be used as sportswear clothing, bag fabrics, work clothes, firefighting clothes, various protective clothing, tent cloth, etc. The fabric used as a bulletproof vest is dyed in an unobtrusive color, and even if it is shot, it only scratches the outer skin. Para-position polyaramid fibers have appeared as bulletproof fabrics, but they have not attracted attention.

Further, examples of products to which the dyed para-aramid fiber of the present invention is applied include seat belts for automobiles, protective clothing for rowers, bowstrings, tennis liners, fishing lines, and the like. When the dyed para-polyaramid fiber of the present invention is used as a fiber reinforcement material for transparent or translucent resin, because the colored reinforcement material can be seen through the transparent or translucent resin, colored Resin products. For example, it is used in the manufacture of resin eyeglass frames, tennis racket frames, table tennis rackets, hockey sticks, fishing rods, golf clubs, etc. When the resin is an elastomer, it can be used to make resin conveyor belts, resin hoses, bicycle tires, etc. The para-position polyaramid fiber of the present invention can also be used to manufacture cables or wires whose production years are indicated by color. When multiple wires are gathered into a bundle, by using reinforcement materials of different colors, it can be used not only as reinforcement for each wire, but also as identification of the end of the wire. In the case of wire sheathing, the sheathing is cut open accordingly to expose the split end, which can also be used as a notch code.

Put the dyed para-type polyaramid fiber filament yarn on the crimping machine, and form 4 to 9 rolls/25mm of crimps (for example, 6 rolls /inch), cut into the fiber length suitable for weaving, that is, 20-150mm, then dyed para-aramide fiber staple fibers can be obtained. The dyed para-aramid fiber can be cut into 0.1-3mm long without bending, and used as wadding for electronic flocking. It is also possible to bend and cut the para-polyaramid fiber of the present invention before dyeing to make short fibers and then dye it. Similarly, dyeing after cutting can also be used as wadding for electronic flocking.

Example

The present invention is illustrated by the following examples. The physical properties in the examples were measured according to the following methods.

(1) Crystal size

Determined by wide-angle X-ray diffraction.

・X-ray diffraction device: manufactured by Rigaku Denki Co., Ltd., type 4036A2

X-ray source: CuKα line

Bending Crystalline Monochromator (using Graphite)

(2) Intrinsic viscosity

It was dissolved in 98.5% (weight) concentrated sulfuric acid to prepare a polymer solution with a concentration (C) = 0.5 g/dl, and the intrinsic viscosity (ηinh) was measured by conventional methods at 30°C.

ηinh=(ln η rel)/C

(3) Strength and elongation characteristics of fibers

The tensile strength and tensile elastic modulus (initial tensile resistance) of the filaments were measured in accordance with JIS-L-1013.

(4) Moisture content

The water content was measured in accordance with JIS-L-1013.

Attached moisture content (%)=(W-W')×100/W'

In the formula, W: the quality of sampling

W': the mass of the sample when it is absolutely dry

(5) L value

The L value is measured in accordance with JIS-Z-8729. As the measuring instrument, Macbeth Color Eyes 3000 manufactured by Sumika Analytical Center Co., Ltd. was used.

Embodiment 1, comparative example 1

Dissolve the PPTA (ηinh=6.5) prepared by the usual method in 99.9% concentrated sulfuric acid to make a spinning dope with a polymer concentration of 19.0% and a temperature of 80°C. From a nozzle with an aperture of 0.06mm and a number of fine holes of 1000, After spraying into the air in a little space, pour it into water at 4°C to solidify it, guide it to a Nelson drum, neutralize it with an 8% aqueous solution of sodium hydroxide, wash it with water, and dry it with a heating roller at 110°C for 15 seconds , continuously wound on a plastic tube to obtain a para-polyaramid fiber A (filament) with a total denier of 1500 denier (converted to absolute dryness) consisting of 1000 filament yarns.

Do not wind the para-type aramid fiber A on the pipe, then guide it to the set hot roller, and then wind it after heat treatment at 350°C for 10 seconds to obtain the dry para-type aramid fiber B (filament).

The physical properties of these para-aramid fibers are shown in Table 1.

Table 1 Fiber type A B Crystal size () 110 direction 42 65 Tensile strength (g/denier) 23.0 22.2 Tensile modulus of elasticity (g/denier) 565 850 Moisture content (%) 48 2.2

These para-type aramid fiber filament yarns were dyed dark blue with the following conditions. "owf" indicates the weight percent of dye in dry fiber weight. g/l represents the weight ratio of the auxiliary agent in the adjusted dyeing bath 1L.

·Dye (cationic dye)

"ASTRAZON Golden GL"

(CI Yellow 28, manufactured by DYSTER): 0.1% owf

"KAYACRYL RED GL"

(CI Red 29, manufactured by Nippon Kayakusha): 2.0% owf

"AIZEN CATHILON BLUE TBLH"

(manufactured by Hodogaya Chemical Co.): 8.0% owf

·Auxiliary

"Neodespon AC" (manufactured by Morin Chemical Co.): 2 g/l

Acetic acid: 1g/l

Sodium nitrate: 20g/l

"Trille Accelerator A III" (manufactured by Meisei Chemical Co.): 20g/l

Take 10g of absolute dry weight of para-type polyaramid fibers, start dyeing at 60°C with a liquor ratio of 1:15, heat up to 130°C in 60 minutes, and dye for 30 minutes. After dyeing, in a bath composed of non-ionic active agent and reducing agent, reduce and wash at 80°C for 20 minutes, dehydrate and dry, and measure the L value. The smaller the value of the L value, the less light is reflected, indicating a darker color. In the case of the same hue, the smaller the value, the better the dyeing. In the dyeing method using the dye bath adjusted as described above, it can be judged that the dyeing has been satisfactorily dyed at a level of L value of 50 or less.

The para-polyaramid fiber A has good dye adsorption, but the para-polyaramid fiber B can hardly be dyed.

Embodiment 2～4, comparative example 2

Place the para-type aramid fiber A at room temperature to evaporate the water, change the water content before dyeing, and dye in the same way as above. Dyeing was good except for Comparative Example 2 with a moisture content of 5%.

Comparative example 3

The para-type aramid fiber A was dried at 100° C. for 60 minutes with a circulating hot air dryer to make the moisture content reach 0%, and dyed under the above conditions. Almost impossible to dye. The results are shown in Table 2.

Table 2 Fiber type Moisture content (%) L value Tensile strength (g/denier) Tensile modulus of elasticity (g/denier) Comparative example 1 B 2.2 65.6 22.2 830 Example 1 A 48 45.4 23.0 565 Example 2 A 45 45.5 23.0 565 Example 3 A 28 45.4 23.0 565 Example 4 A 12 46.0 23.0 565 Comparative example 2 A 5 50.2 23.0 565 Comparative example 3 A 0 65.2 23.0 565

Example 5

Wrap the para-type polyaramid fiber A thread without twisting on a plastic tube with an inner diameter of 51mm, an outer diameter of 57mm, and a length of 250mm at a tension of 0.04g/denier. The part where the thread is wound has a hole with a diameter of 8mm Multiple, the amount of winding converted into absolute dry weight is 1kg. The dyeing is carried out under the conditions described above with a cheese dyeing device in which the dye solution is in the above-mentioned plastic tube through which the filaments flow to the outside of the cheese. The moisture content of the para-aramid fiber before dyeing was 48%. As the temperature rises during dyeing, some water is released from the para-aramid fiber A, which reduces the volume and creates gaps between the fibers, and the dye solution is easy to circulate. The L value of the para-aramid fiber A after dyeing was 45.5, and the dyeing was good. The dyed para-position polyaramid fiber has a tensile strength of 23.0g/denier and a tensile elastic modulus of 565g/denier, a para-position polyaramid fiber with high strength and high modulus of elasticity, It fully satisfies the characteristics of the para-type polyaramid fiber.

Comparative example 4

Twisting the sliver of the para-type polyaramid fiber A with a ring twisting machine, the number of twists is 74 times/m, which is equivalent to the twist coefficient=1 represented by the following formula. This twisted yarn was dyed in the same way as in Example 5. The filament sliver has a circular cross-sectional shape by twisting. In the state of being wound on the plastic tube, since spaces are formed between the fibers, the circulation of the dye solution is better than that of Example 5 during dyeing. However, partially low concentration and insufficiently stained sites were produced.

The moisture in the filament yarn can be released by the action of the balloon during twisting and the centrifugal force applied to the rotating fan, and water droplets can be observed to scatter around the twisting machine. As a result, in the longitudinal direction of the para-type aramid fiber, a part with less moisture is partially formed, and the dyeing of this part is insufficient.

$\mathrm{<span\; class="notranslate">\; K</span>}<span\; class="notranslate">\; =</span><span\; class="notranslate">\; (</span>\mathrm{<span\; class="notranslate">\; T</span>}\sqrt{\mathrm{<span\; class="notranslate">\; D.</span>}}<span\; class="notranslate">\; )</span><span\; class="notranslate">\; /</span>\mathrm{<span\; class="notranslate">\; 2870</span>}$

K: Twist coefficient

T: number of twists (times/m)

D: Denier when absolutely dry (denier)

According to the present invention, it is possible to provide poly-p-phenylene terephthalamide fibers which can be dyed while maintaining high strength and high modulus of elasticity, and poly-p-phenylene terephthalamide fibers dyed in various colors.

Possibility of industrial use

The invention provides poly-p-phenylene terephthalamide fibers that can be dyed while maintaining high strength and high elastic modulus, and poly-p-phenylene terephthalamide fibers dyed in various colors. The para-position polyaramid fiber of the present invention has multiple uses, especially the dyed para-position polyaramid fiber filament yarn, which can be used as sewing machine threads, cords, ropes and fabrics of various colors. The para-aramide fiber fabric with rich color and luster obtained by the invention can be used as sportswear material, bulletproof vest, bag fabric, work clothes, firefighting clothes, various protective clothing materials and tent fabrics.

Claims (12)

1. Fanglun 1414 that can dye, after it is spinning, once twining becomes the preceding Fanglun 1414 of dyeing, it is characterized in that, its TENSILE STRENGTH is more than the 15g/ DENIER, crystal size (110 direction) is 30～55 , and moisture is generally more than 8%.

2. the Fanglun 1414 that can dye of claim 1 record is characterized in that not having moisture in the dry course below 15%.

3. the staple fibre shape Fanglun 1414 that can dye is characterized in that, gives curling of 4～9 volume/25mm to the fiber of claim 1 or 2 records, and is cut into the fibre length of 20～150mm.

4. a cotton for wadding shape Fanglun 1414 is characterized in that, the fiber of claim 1 or 2 records is cut into 0.1～3mm.

5. a dyeing Fanglun 1414 is characterized in that, the stock-dye of claim 1 or 2 records is formed.

6. the dyeing Fanglun 1414 of record in the claim 5 is characterized in that, the usefulness cationic dyeing.

7. a staple fibre shape dyeing Fanglun 1414 is characterized in that, the staple fibre shape Fanglun 1414 dyeing of claim 3 record is formed.

8. the short fiber shape dyeing Fanglun 1414 of claim 7 record is characterized in that, the usefulness cationic dyeing.

9. cotton for wadding shape dyeing Fanglun 1414 is characterized in that, the cotton for wadding shape Fanglun 1414 of claim 4 record is dyeed to form.

10. the cotton for wadding shape dyeing Fanglun 1414 of claim 9 record is characterized in that, the usefulness cationic dyeing.

11. the Fanglun 1414 that can dye manufacture method, this method is, make spinning stoste by having the PPTA and the concentrated sulfuric acid of inherent viscosity (η inh) more than 5, and allow the pore of this spinning solution by spinning-nozzle, once be sprayed onto in the air, import immediately it is solidified, form high strength, the operation of high elastic modulus filament yarn, and the discontinuous dyeing process of this filament yarn, and the method for in each operation, implementing, it is characterized in that, in this method, its TENSILE STRENGTH of the fiber of making reaches more than the 15g/ DENIER, and crystal size (110 direction) reaches 30～55 , and the moisture of fiber generally remains on more than 8%.

12. colouring method, this method is the Fanglun 1414 that can dye who makes with the method for claim 11 record, under the twist coefficient of representing with following formula is twisting count below 0.2, carry out the dyeing of cone dyeing method with cation dyes.

$K=\left(T\sqrt{D}\right)/2870$

K: twist coefficient

T: add twisting count (inferior/m)

D: the fiber number during adiabatic drying (DENIER)