RU2744118C1 - Method for dying aramide fiber - Google Patents

Abstract

FIELD: fiber dying.

SUBSTANCE: invention relates to the field of technology for producing dyed heat- and fire-resistant aramid yarns and can be used in the chemical industry directly in the production of aramid yarns. A method for dyeing aramid fiber by introducing an acidic metal-containing dye at the stage of polymer synthesis or after polymer synthesis with subsequent spinning of a fiber from a solution based on aprotic amide solvents by a wet or dry-wet method is described. Aramid fiber is dyed with acid metal-containing dyes, with a general formula of Ме(-О-)₂Кр(-SO₃Na)_n, in an amount of 0.5-5.0% by weight of the polymer.

EFFECT: proposed method makes it possible to obtain uniform and intense colors of a wide range, resistant to washing and friction while maintaining high physical and mechanical properties.

4 cl, 2 tbl

Description

FIELD OF TECHNOLOGY

The invention relates to the field of chemical technology for producing dyed thermo- and fire-resistant aramid fibers and can be used in the chemical industry directly in the production of aramid fibers and threads.

LEVEL OF TECHNOLOGY

The combination of high physical, mechanical and thermal characteristics of aramid yarns makes it possible to use them for the manufacture of protective clothing. Therefore, when dyeing aramid yarns and fabrics, great importance is attached to the achievement of intense, uniform and stable color while maintaining the performance of the textile material. Aramid fabrics are difficult to stain with dyes, since they have a dense structure, high crystallinity of the polymer and a low content of functional groups that can interact with the dye.

In order to facilitate the process of obtaining a dyed aramid fabric, it is necessary to dye a solution of the polymer in the mass and then to form the dyed threads in the mass.

Combining the synthesis of polymers or the spinning of threads from their solutions or melts with the dyeing process is called bulk dyeing.

These requirements are met by the methods of dyeing aramid fibers at the stages of synthesis [RF Patent 2210649. AV Volokhina. and other Method of dyeing aramid fibers, publ. 20.08.2003., IPC: D06P 3/04, D06P 3/24, D01F 8/08]. For spinning fibers from a solution based on aprotic amide solvents by wet or dry-wet method, a mixture of polymers of aromatic polyamide and polyacrylonitrile is used at a content of the latter of 1.5-20 wt%, followed by heat treatment at 240-350 ° C for 20 minutes. Aramid fiber acquires a dark brown or black color, while the strength indicators not only do not decrease, but in some cases increase. However, a significant disadvantage of the proposed method is the release of toxic volatile substances during heat setting.

Periodic and continuous methods of dyeing aramid fibers using intensifying agents of various chemical nature are widely used. The work [Nechwatal A., Rossbach V. The carrier effect in the m-aramid fiber / cationic dye / benzyl alcohol system // Textile research journal Vl. 69, Is.9, Sep.1999, 635-641] shows the effectiveness of using benzyl alcohol, acetophenone, dimethylacetamide and dimethyl sulfoxide when dyeing meta-aramid fibers with cationic dyes. It is proposed to use a cationic dye in an amount of 2% by weight of the fiber and benzyl alcohol with a concentration of 70 g / l for dyeing from an aqueous solution in the presence of 20 g / l sodium nitrate and 2.5% acetic acid with a bath modulus of M = 20. Dyeing is carried out on batch machines for 60 minutes at 125 ° C. The analysis of coloristic and physical and mechanical properties showed that the strength of the paint to friction and wet treatments is 5 and 3-4 points, respectively, the breaking load is reduced by 18%. In US patent [US patent 6840967. Riggins P., Hansen J. Dye diffusion promotion for aramids, publ. 11.01.2005, IPC: D06P 1/64, D06P 3/24, D06P 3/26] describes a method for dyeing aramid fibers using alkyl-substituted amides containing 7-14 carbon atoms. Dyeing Nomex and Kevlar fibers, as well as their mixtures, in the presence of the proposed intensifier at 100-150 ° C and increased pressure provides an improvement in fire-retardant performance (CI) by 3-20%.

Known methods for dyeing aramid fibrous materials with pretreatment in polar solvents. It was found that the pre-treatment of the fiber in an ammonia solution affects the substantive properties of the cationic dye, while the increase in dyeing is accompanied by a decrease in the physical and mechanical strength [Nicolai M., Nechwatal A. The swelling effect of liquid-ammonia in the dyeing of aramid // Journal of the society of dyers and colorists Vl. 110, Is. 7-8, Jul-Aug 1994, 228-230]. It is possible to increase the coloring and preserve the physical and mechanical properties if, before dyeing with cationic and direct dyes, the fiber is treated with either adipic acid chloride or benzoic acid chloride [Yoo Hj., Ravichandran V., Ovendorf Sk. Pretreatments for improving the dyeability of p-aramid fiber // Textile research journal Vl. 64, Is.7, Jul. 1994, 423-426].

Also known is a method that includes several stages. The Arlan aramid fiber is pretreated with a mixture that contains a solvent dimethylacetamide, or dimethylformamide, or dimethylsulfoxide, or a mixture thereof, a lower methyl alcohol, or ethyl alcohol, or ethylene glycol, or glycerol, or another, and / or water in various ratios at 18-20 ° C for 5 to 60 minutes, followed by rinsing or without rinsing. This is followed by dyeing with dispersed or cationic dyes in a periodic manner at a boiling point for 30-60 minutes, followed by washing with warm and cold water for 10-15 minutes. [Manyukov E.A. Substantiation and development of rational technology for dyeing domestic heat-resistant fiber Arlan [Text]: dissertation author's abstract for the degree of Candidate of Science. tech. Sciences: 05.19.02 / E.A. Manyukov. - M., 2005 .-- 16 p: ill. - Bibliography: p.15-16 (10 titles). - Ap06-3807], [Patent RU 2255160 C1 Method for dyeing metaparamidbenzimidazole fiber, E.A. Manyukov, publ. June 27, 2005, IPC: D06P 3/04, D06P 3/24]. By this method, it is possible to obtain intense stable colors. The disadvantage of this method is the use of toxic and flammable substances. So ethyl and methyl alcohols are flammable liquids, while the latter is a strong poison. The offered solvents dimethylacetamide, dimethylformamide, dimethylsulfoxide are classified as toxic substances with an unpleasant odor of hazard class 3 (MPC 10 mg / m ³ ). The compositions proposed by the prototype create unfavorable working conditions during the preparation of the pre-treatment bath, in the service area of the dyeing equipment, as well as during the heat treatment of the material. In addition, the structurally bound polar solvent remains on the fiber after dyeing and washing, and during operation can be released and have a toxic effect [Patent RU 2362851 C1 Method for dyeing aramid fibers. Mikhailovskaya A.P. and others, publ. 07/27/2009, IPC: D06P 3/04, D06P 3/24]. A method of dyeing aramid fiber, which consists in pretreating the fiber with an aqueous solution including an intensifier and dyeing during boiling of a dyeing solution followed by washing, characterized in that the pretreatment is carried out in a bath of the following composition, wt%: gelatin - 20-25, complex salt based on aluminum oxide - 1-3, acetic acid - 3-4, water - the rest, and staining is carried out for 30-40 minutes in a bath of the following composition, wt%: acid dye - 2.5-10, acetic acid - 3-4, water is the rest.

DISCLOSURE OF THE INVENTION

A significant difference of the proposed method is dyeing at the stage of polymer synthesis or after the end of polymer synthesis with acidic metal-containing dyes with the general formula Me (-O-) ₂ Cr (-SO ₃ Na) _n , where Me is a metal ion of chromium, cobalt, copper, nickel; n is the number of sulfo groups from 0 to 2. For example, Ostalan Black S-RQ, Ostalan Brown PN (Mixture), Ostalan Gray BL, Ostalan Gray PN (Mixture), Lanegal Green G, Lanegal Blask B (Mixture), Lanegal Red 2В ( Mixture), Lanegal Blue 2R.

The technical objective of the invention is to eliminate the disadvantages of the prior art, to create an environmentally friendly method for dyeing aramid fiber, in which the dye is completely fixed on the fiber, which makes it possible to exclude the ingress of the dye into the drains.

In addition, the claimed method of dyeing aramid fibers, at the stage of preparation of the spinning solution, has advantages over the prior art in terms of reducing the cost of the process for producing dyed fibers, since it does not require additional production capacity and can be implemented on existing equipment under conditions for the production of aramid yarns.

The technical result consists in obtaining fibers that are resistant to washing and friction while maintaining high physical and mechanical properties, uniform and intense coloring of a wide range of colors.

The claimed technical result is achieved by a method of dyeing meta, para-aramid fibers, including the introduction of a solution of an acidic metal-containing dye in an aprotic amide solvent at the stage of polymer synthesis or after the end of polymer synthesis, followed by spinning the fiber from the solution by a wet or dry-wet method, followed by heat treatment at 180-400 ° C for 5-120 minutes, while the mass fraction of the dye is 0.5-5.0% by weight of the polymer. In this case, the acidic metal-containing dye is represented by the general formula Me (-O-) ₂ Cr (-SO ₃ Na) _n , where Me is the metal ion of chromium, cobalt, copper, nickel; n is the number of sulfo groups from 0 to 2. For example, Ostalan Black S-RQ, Ostalan Brown PN (Mixture), Ostalan Gray BL, Ostalan Gray PN (Mixture), Lanegal Green G, Lanegal Blask B (Mixture), Lanegal Red 2В ( Mixture), Lanegal Blue 2R. In this case, as an aprotic amide solvent, for example, dimethylacetamide, dimethylformamide, dimethylsulfoxide can be used. In this case, a polymer from an aromatic polyamide of the meta, para structure was synthesized from 30-70 mol.% 5 (6) -amino-2-paraaminophenylbenzimidazole, 30-70 mol.% Paraphenylenediamine (metaphenylenediamine) and 100 mol.% Terephthaloyl chloride (isophthaloyl chloride).

The above and other objects, features, advantages, as well as the technical significance of the present invention will be better understood from the following detailed description of the invention and examples of its implementation.

CARRYING OUT THE INVENTION

Method 1. Introduction of a dye at the stage of polymer synthesis

Example 1

A solution of Lanegal Blask B (Mixture) dye in an aprotic solvent (dimethylacetamide) is introduced into a solution of diamines 5 (6) -amino-2-paraaminophenylbenzimidazole (2.8361 mol / 70% mol) and paraphenylenediamine (1.2155 mol / 30% mol) , the amount of dye is 0.5% (7.58 g) by weight of the resulting polymer, then the acidic component terephthaloyl chloride (4.0515 mol) is introduced.

Wet-spun aramid thread from a mass-dyed polymer is heat treated at 180 ° C for 120 minutes.

Example 2

A solution of the Ostalan Brown PN dye (Mixture), in an aprotic solvent (dimethyl sulfoxide), is introduced into a solution of diamines 5 (6) -amino-2-paraaminophenylbenzimidazole (2.0258 mol / 50% mol) and paraphenylenediamine (2.0258 mol / 50% mol ), the amount of dye is 1.0% (14.22 g) of the mass of the resulting polymer, then the acidic component terephthaloyl chloride (4.0515 mol) is introduced.

Wet-spun aramid thread from a mass-dyed polymer is heat treated at 300 ° C for 60 minutes.

Example 3

A solution of the Ostalan Black S-RQ dye in an aprotic solvent (dimethylformamide) is introduced into a solution of diamines 5 (6) -amino-2-paraaminophenylbenzimidazole (1.21545 mol / 30% mol) and paraphenylenediamine (2.83605 mol / 70% mol), the amount of dye is 1.5% (19.92 g) by weight of the resulting polymer, then the acidic component terephthaloyl chloride (4.0515 mol) is introduced.

Aramid thread, formed by the dry-wet method from a polymer dyed in the mass, is heat treated at a temperature of 400 ° C for 5 minutes.

Example 4

The same as in example 1, differs in that instead of paraphenylenediamine, metaphenylenediamine is used, the acid component is isophthaloyl chloride, and a solution of the Ostalan Gray BL dye is used, the amount of dye is 2.0% (30.32 g) of the mass of the resulting polymer.

Example 5

The same as in example 2, differs in that instead of paraphenylenediamine, metaphenylenediamine is used, the acid component is isophthaloyl chloride, and the dye Ostalan Gray PN (Mixture) is also used, the amount of dye is 2.5% (35.55 g) of the mass obtained polymer.

Example 6

The same as in example 3, differs in that instead of paraphenylenediamine, metaphenylenediamine is used, the acid component is isophthaloyl chloride, and Lanegal Blue 2R dye is also used, the amount of dye is 4.0% (53.12 g) of the mass of the resulting polymer.

Example 7

The same as in example 1, differs in that the dye Lanegal Green G is used, the amount of dye is 3.5% (53.06 g) by weight of the resulting polymer.

Example 8

The same as in example 2, differs in that the amount of dye is 4.5% (63.99 g) by weight of the resulting polymer.

Example 9.

The same as in example 3, differs in that the amount of dye is 5.0% (66.4 g) by weight of the resulting polymer.

Example 10

The same as in example 1, differs in that the dye Lanegal Red 2B (Mixture) is used, the amount of the dye is 3.0% (45.48 g) by weight of the resulting polymer.

Method 2. Introduction of the dye after the end of the polymer synthesis.

Example 11

A solution of the Ostalan Brown PN dye (Mixture in an aprotic solvent (dimethylformamide) is introduced into the polymer solution after the end of the synthesis, the amount of the dye is 0.5% (7.58 g) of the polymer weight.

Aramid yarn, wet-spun from a mass-dyed polymer, is heat treated at 180 ° C for 120 minutes.

Example 12

The same as in example 11, differs in that the dye Ostalan Black S-RQ is used, the aramid thread, wet-spun from the polymer dyed in the mass, is heat treated at a temperature of 300 ° C for 60 minutes.

Example 13

The same as in example 11, differs in that the dye Ostalan Gray BL is used, an aramid thread, formed by a dry-wet method from a polymer dyed in the mass, is heat treated at a temperature of 400 ° C for 5 minutes.

Example 14

The same as in example 11, differs in that the dye Ostalan Gray PN (Mixture) is used, the amount of the dye is 1.0% (15.16 g) by weight of the obtained polymer.

Example 15

The same as in example 12, differs in that the dye Lanegal Green G is used, the amount of the dye is 2.0% (30.32 g) of the weight of the obtained polymer.

Example 16

The same as in example 13, differs in that the dye Lanegal Blac B (Mixture) is used, the amount of dye is 2.5% (37.90 g) by weight of the obtained polymer.

Example 17

The same as in example 11, differs in that the dye Lanegal Red 2B (Mixture) is used, the amount of the dye is 3.0% (45.48 g) by weight of the obtained polymer.

Example 18

The same as in example 12, differs in that the dye Lanegal Blue 2R is used, the amount of dye is 3.5% (53.06 g) of the weight of the obtained polymer.

Example 19

The same as in example 13, differs in that the amount of dye is 4.0% (60.64 g) by weight of the obtained polymer.

Example 20

The same as in example 12, differs in that the amount of dye is 5.0% (75.8 g) by weight of the obtained polymer.

The test for the resistance to washing of dyed aramid yarns from them was carried out in accordance with GOST 9733.4-83. The test of color fastness to friction was carried out in accordance with GOST 9733.27-83.

The color fastness to washing and dry abrasion of the dyed aramid yarns obtained according to Examples 1-20 is shown in Table 1.

Table 1. Color fastness of aramid yarns to washing and dry friction.

No.
p.p. Dyeing method Color fastness to washing in points on a 5-point scale Color fastness to dry friction Dye black Dye gray Dye green Dye black Dye gray Dye green one As in example 1 5/5/5 5/5/5 5/5/5 five five five 2 As in example 2 5/5/5 5/5/5 5/5/5 five five five 3 As in example 3 5/5/5 5/5/5 5/5/5 five five five four As in example 4 5/5/5 5/5/5 5/5/5 five five five five As in example 5 5/5/5 5/5/5 5/5/5 five five five 6 As in example 6 5/5/5 5/5/5 5/5/5 five five five 7 As in example 7 5/5/5 5/5/5 5/5/5 five five five 8 As in example 8 5/5/5 5/5/5 5/5/5 five five five 9 As in example 9 5/5/5 5/5/5 5/5/5 five five five ten As in example 10 5/5/5 5/5/5 5/5/5 five five five eleven As in example 11 5/5/5 5/5/5 5/5/5 five five five 12 As in example 12 5/5/5 5/5/5 5/5/5 five five five thirteen As in example 13 5/5/5 5/5/5 5/5/5 five five five 14 As in example 14 5/5/5 5/5/5 5/5/5 five five five 15 As in example 15 5/5/5 5/5/5 5/5/5 five five five 16 As in example 16 5/5/5 5/5/5 5/5/5 five five five 17 As in example 17 5/5/5 5/5/5 5/5/5 five five five eighteen As in example 18 5/5/5 5/5/5 5/5/5 five five five 19 As in example 19 5/5/5 5/5/5 5/5/5 five five five 20 As in example 20 5/5/5 5/5/5 5/5/5 five five five

The examples in the table illustrate the production of uniform, intense and friction-resistant paints. The used brands of dyes are resistant to the action of the solvent used to prepare the polymer solution and high temperatures in thermal imidization modes.

Physicomechanical characteristics of heat-treated filaments dyed with acidic metal-containing dyes at the stage of synthesis or after polymer synthesis, and for comparison of unpainted heat-treated filaments, are presented in Table 2.

Table 2. Physical and mechanical characteristics of the dyed yarns obtained according to examples 1-20.

Thread received Linear density of a thread, tex Specific breaking load, cN / tex Elongation at break,% Elastic modulus, GPa Specific work of breaking, J / tex Unpainted para-aramid thread 29.2 289 3.0 146 49 Unpainted meta-aramid thread 29.4 212 2.4 104 32 As in example 1 29.1 279 2.7 144 46 As in example 2 29.4 280 2.8 147 49 As in example 3 29.3 270 2.6 135 44 As in example 4 29.6 217 2,3 109 32 As in example 5 29.5 210 2,3 106 32 As in example 6 29.2 190 2.2 106 29 As in example 7 29.3 274 2.7 140 44 As in example 8 29.4 280 2.9 144 46 As in example 9 29.3 278 2.6 140 44 As in example 10 29.3 269 2.6 139 44 As in example 11 29.2 276 2.7 143 44 As in example 12 29.3 274 2.7 139 44 As in example 13 29.1 282 2.8 145 49 As in example 14 29.2 268 2.6 138 43 As in example 15 29.1 280 2.8 146 49 As in example 16 29.4 277 2.8 144 48 As in example 17 29.3 274 2.7 140 45 As in example 18 29.2 269 2.6 139 43 As in example 19 29.1 280 2.8 145 49 As in example 20 29.3 278 2.8 144 48

Thus, in the process of dyeing aramid threads at the stage of synthesis or after the synthesis of the polymer with acidic metal-containing dyes, high physicomechanical characteristics of the dyed threads are maintained at a level not lower than the original thread. Since the dye is evenly distributed in the polymer even before the filaments are formed, the resulting dyes are distinguished by exceptional resistance to all types of physical and chemical influences and high evenness.

Claims (4)

1. A method of dyeing meta-, para-aramid fibers, including the introduction of a solution of an acidic metal-containing dye in an aprotic amide solvent at the stage of polymer synthesis or after the end of polymer synthesis, followed by spinning the fiber from a solution by a wet or dry-wet method, followed by heat treatment at 180-400 ° C for 5-120 minutes, while the mass fraction of the dye is 0.5-5.0% by weight of the polymer. 2. The method according to claim 1, in which the acidic metal-containing dye is represented by the general formula Me (-O-) ₂ Cr (-SO ₃ Na) _n , where Me is a metal ion of chromium, cobalt, copper, nickel; n is the number of sulfo groups from 0 to 2. 3. The method according to PP. 1, 2, in which the aprotic amide solvent is selected from the group of dimethylacetamide, dimethylformamide, dimethylsulfoxide. 4. The method according to PP. 1-3, in which a polymer of an aromatic polyamide meta, parastructure is synthesized from 30-70 mol.% 5 (6) -amino-2-paraaminophenylbenzimidazole, 30-70 mol.% Paraphenylenediamine or metaphenylenediamine and 100 mol.% Terephthaloyl chloride or isophthaloyl chloride ...