Preparation method of a dyeable seaweed fiber

Abstract

The invention discloses a preparation method of dyeable seaweed fiber, belonging to the technical field of textile chemical engineering. It mainly solves the technical limitations that existing seaweed fibers are not salt-tolerant and cannot be dyed, which is a technical breakthrough for dyeing seaweed fibers. First, fiber-grade sodium alginate powder is made into a spinning solution, and by using wet spinning equipment and process, after coagulation, drawing, and water washing, seaweed fiber is obtained after cross-linking post-treatment and drying. During the production process, water-soluble aluminate can be added in any and all processes of the spinning solution, coagulation bath, and cross-linking, and then dyeable seaweed fiber can be obtained. The seaweed fiber prepared by the method of the invention is dyed with reactive dyes, the dye uptake rate of the dye on the fiber is greater than or equal to 60%, the fiber strength damage is small, and the soaping fastness is ≥4 levels.

Description

Technical Field

[0001] The present invention belongs to the technical field of textile chemicals, and particularly relates to a preparation method of a dyeable seaweed fiber. Background Art

[0002] Seaweed fiber is a new type of biomass fiber prepared from alginic acid extracted from natural seaweed by a specific spinning method. Alginic acid polysaccharide consists of two components, β-D-mannuronic acid and α-L-guluronic acid. The salts formed by alginic acid and most divalent and higher metal ions are insoluble in water. Therefore, sodium alginate can be dissolved in water to prepare a spinning dope, and then alginic acid fiber can be prepared by wet spinning. Usually, sodium alginate is used as the spinning matrix, and an aqueous solution containing metal ions such as Ca 2+ , Cu 2+ , Ba 2+ , Zn 2+ etc., is used as a coagulation bath, and it is prepared by the method of wet spinning. Divalent calcium ions are ionically bonded to carboxylic acid groups on adjacent alginic acid molecular chains, and calcium ions are surrounded between adjacent molecular chains to form an "egg box" structure. It has attracted attention due to its good biodegradability and compatibility, excellent moisture absorption and easy removal properties, film-forming and fiber-forming properties, and self-flame retardancy. At present, it has been widely used in the field of medical dressings and also has great potential in high-grade clothing, underwear fabrics and decorative textiles. However, it has been found that seaweed fiber has poor acid-base tolerance, and when it encounters ionic solutions such as N + , Na + , K + etc., the fiber will swell and even dissolve.

[0003] Part of the carboxyl groups in the molecular structure of seaweed fiber exist in the form of chelation with calcium ions. The fiber is negatively charged because these carboxyl groups ionize in aqueous solution; direct dyes and reactive dye molecules are also negatively charged in aqueous solution. Under the repulsive force of the same charge, the dyeing rate of seaweed fiber with direct dyes or reactive dyes is relatively low, and the dyes are adsorbed on the surface of the seaweed fiber as floating colors. This results in difficulties in dyeing seaweed fiber in the current dyeing system.

[0004] At present, there are some reports on the research of seaweed fiber dyeing in the existing technologies, mainly including: traditional dyeing methods, coloring of spinning dope, fiber modification, and development of special dyes.

[0005] As described in CN101736440A, a method for manufacturing a dyeable alginate fiber is disclosed. In this application, a water-soluble dendrimer is added to the alginate fiber spinning solution. Using a wet spinning device and process, through coagulation, drawing, water washing, and post-treatment, a dyeable alginate fiber is obtained. The key to this method is adding a dendrimer to the spinning solution. Adding macromolecules to the spinning solution will inevitably increase the viscosity of the spinning solution, thereby increasing the difficulty of spinning. In actual production, it is necessary to reduce the spinning speed, and the spinneret holes are often blocked and the filaments are broken. Therefore, it is difficult to apply this method industrially. And this method is based on the reactive dyeing process. Although the dyeing of alginate fibers is achieved to a certain extent, the dendrimer cannot protect the alginate fibers, and the fiber strength is severely damaged, making it difficult to apply industrially.

[0006] Chinese Patent CN113249823B, alginate fiber and its preparation method. In this patent, a quaternary ammonium salt polymer with a five-membered ring is added during the spinning process, and the prepared alginate fiber has the ability to be dyed. Although this patented technology can achieve the dyeing of alginate fibers, the additives used are cationic macromolecules, which are likely to cause uneven dyeing and ring dyeing problems.

[0007] Chinese Patent CN103981744A, a salt-free dyeing method for calcium alginate fibers. In this patent, an aqueous solution of aluminum sulfate is first used to pretreat the calcium alginate fibers to be dyed, then direct dyes are used for salt-free dyeing, and finally an aqueous solution of calcium chloride is used for fixing. This patent has made great progress in improving the dyeing depth, but the use of a large amount of calcium chloride for fixing will calcify the fibers and lose the flexibility of the fibers.

[0008] Wang Ping, Zhang Liping, Tian Anli, etc. Influence of fluorescent pigments on the properties of alginate fiber spinning solution and its membrane [J]. Journal of Textile Research, 2015, 36(05): 48-53. introduced a method of coloring by blending fluorescent pigments / alginate fiber spinning dope. However, the coloring depth and color fastness effects using fluorescent dyes are not ideal enough.

[0009] Chinese Patent CN109183447A, a reactive dye salt-free dyeing method for calcium alginate fibers. This method uses polyvinylamine as an additive to pretreat the fibers, and a large number of primary amino groups carried form ionic bond combinations with the dyes. However, there are problems such as difficult synthesis and high cost of polyvinylamine.

[0010] Chinese Patent CN108342912B discloses a method for dyeing alginate fibers with polycarboxylic acid type dyes. This method mainly dyes alginate fibers by developing a special polycarboxylic acid type dye. A large number of carboxyl groups on the dye form a complex structure with the metal ions of the alginate fibers, enabling the dye macromolecules to be fixed on the fibers. The deficiencies of this method are that the synthesis process of the special dye is complex, the cost is high, and the applicable range is narrow. Summary of the Invention

[0011] In order to further solve the defects existing in the above-mentioned prior art, the present invention provides a preparation method of a dyeable seaweed fiber. The seaweed fiber prepared by this method can be dyed in an alkaline system, protecting the seaweed fiber to the greatest extent.

[0012] To solve the above technical problems, the present invention adopts the following technical solutions:

[0013] A preparation method of a dyeable seaweed fiber, comprising the following steps:

[0014] S1. Preparation of the spinning solution: Dissolve sodium alginate and water-soluble aluminate in water and mix evenly to obtain a sodium alginate spinning solution;

[0015] S2. Coagulation and shaping of the fiber: Let the spinning solution obtained in step S1 stand for defoaming and then extrude it into an aqueous coagulation bath solution at 40-70 °C for coagulation and shaping. After stretching, rinsing, and drying, a seaweed fiber containing water-soluble aluminate is obtained;

[0016] S3. Post-treatment of the fiber: Contact and soak the seaweed fiber obtained in step S2 with an auxiliary agent solution at 20-70 °C for 5-60 minutes. After soaking, rinse and dry to obtain the dyeable seaweed fiber.

[0017] Further, in step S1, the water-soluble aluminate is one or more of potassium alum, potassium meta-aluminate, sodium meta-aluminate, and barium meta-aluminate.

[0018] Further, in step S1, the mass ratio of sodium alginate to water-soluble aluminate is 40:0 to 5 g.

[0019] Further, in step S1, the concentration of sodium alginate in the sodium alginate spinning solution is 3-7.5 wt%.

[0020] Further, in step S2, the aqueous coagulation bath solution is a mixed solution of calcium chloride and water-soluble aluminate.

[0021] Further, the water-soluble aluminate in the aqueous coagulation bath solution is one or more of potassium alum, potassium meta-aluminate, sodium meta-aluminate, and barium meta-aluminate.

[0022] Further, the concentration of calcium chloride in the aqueous coagulation bath solution is 4-6 wt%.

[0023] Further, the concentration of water-soluble aluminate in the aqueous coagulation bath solution is 0-2 wt%.

[0024] Further, in step S3, the auxiliary agent in the auxiliary agent solution is one or more of potassium alum, potassium meta-aluminate, sodium meta-aluminate, and barium meta-aluminate.

[0025] Further, in step S3, the concentration of the auxiliary agent in the auxiliary agent solution is 0.1-0.6 wt%.

[0026] Further, in step S3, the mass ratio of the seaweed fiber to the auxiliary agent in the auxiliary agent solution is 15-40:1.

[0027] The present invention provides the seaweed fiber prepared by the above method.

[0028] The application of the seaweed fiber provided by the present invention in the fields of textile and clothing.

[0029] The present invention also provides a method for dyeing seaweed fiber with high dye uptake and less fiber damage, comprising the following steps:

[0030] (1) Preparation of the spinning solution: Dissolve sodium alginate and water-soluble aluminate in water and mix evenly to obtain a sodium alginate spinning solution;

[0031] (2) Fiber coagulation and forming: Let the spinning solution obtained in step S1 stand for defoaming and then extrude it into a coagulation bath aqueous solution at 40-70 °C for coagulation and forming. After stretching, rinsing and drying, a seaweed fiber containing water-soluble aluminate is obtained;

[0032] (3) Fiber post-treatment: Contact the seaweed fiber obtained in step S2 with the auxiliary agent solution at 20-70 °C and soak for 5-60 minutes. After soaking, rinse and dry to obtain a dyeable seaweed fiber;

[0033] (4) Dyeing: Weigh 1-2% of the reactive dye according to the mass of the dyeable seaweed fiber, prepare a dyeing solution according to a bath ratio of 1:20-30. When the dyeing solution is heated to 30-35 °C, put the dyeable seaweed fiber into the dyeing solution, and then heat the dyeing solution at a rate of 1-2 °C / min to 70-80 °C, then add 4-5 g / L of water-soluble aluminate for 40-50 min of color fixation. After that, take out the seaweed fiber and put it into a neutral detergent of 4-5 g / L, oscillate at 90-95 °C for 5-10 minutes, and then dry to obtain the dyed seaweed fiber.

[0034] In one embodiment of the present invention, in step (1), the water-soluble aluminate is one or more of potassium alum, potassium meta-aluminate, sodium meta-aluminate, and barium meta-aluminate.

[0035] Further, in step (1), the mass ratio of sodium alginate to water-soluble aluminate is 40:0-5 g.

[0036] Further, in step (1), the concentration of sodium alginate in the sodium alginate spinning solution is 3-7.5 wt%.

[0037] Further, in step (2), the coagulation bath aqueous solution is a mixed solution of calcium chloride and water-soluble aluminate.

[0038] Further, the water-soluble aluminate in the coagulation bath aqueous solution is one or more of potassium alum, potassium meta-aluminate, sodium meta-aluminate, and barium meta-aluminate.

[0039] Further, the concentration of calcium chloride in the coagulation bath aqueous solution is 4-6 wt%.

[0040] Further, the concentration of water-soluble aluminate in the coagulation bath aqueous solution is 0-2 wt%.

[0041] Further, in step (3), the auxiliary agent in the auxiliary agent solution is one or more of potassium alum, potassium meta-aluminate, sodium meta-aluminate, and barium meta-aluminate.

[0042] Further, in step (3), the concentration of the auxiliary agent in the auxiliary agent solution is 0.1-0.6 wt%.

[0043] Further, in step (3), the mass ratio of the seaweed fiber to the auxiliary agent in the auxiliary agent solution is 15-40:1.

[0044] The present invention provides the dyed seaweed fiber prepared by the above method.

[0045] The application of the dyed seaweed fiber provided by the present invention in the fields of textile and clothing.

[0046] The beneficial effects brought by the present invention are as follows:

[0047] 1. The present invention uses spinning crosslinking and post-finishing processes, selects appropriate raw materials, ratios, and reaction conditions, constructs dyeable groups inside and on the surface of the seaweed fiber, and simultaneously closes some hydroxyl groups of the seaweed fiber to achieve the salt tolerance of the seaweed fiber; thereby preparing a dyeable seaweed fiber, thus solving the bottleneck problem of the industrial application of current seaweed fibers.

[0048] 2. The fiber production process of the present invention is simple, easy to operate, the dyed color is bright, the dye uptake rate is relatively high, all fastnesses are good, the fiber maintains its original morphology during the dyeing process, no obvious dissolution phenomenon occurs, and the mechanical properties do not decrease significantly, having good prospects for commercialization and industrialization of seaweed fibers. Specific Embodiments

[0049] In order to make the advantages and technical solutions of the present invention clearer and more definite, the present invention will be described in detail below with specific embodiments.

[0050] Example 1

[0051] (1) Dissolve 40 g of sodium alginate and 1 g of potassium alum in water to prepare 1000 g of solution as the spinning solution.

[0052] (2) Prepare an aqueous solution of 5% calcium chloride + 1% potassium metaaluminate by mass percentage as the coagulation bath aqueous solution. After standing and degassing the spinning solution, extrude it into the coagulation bath aqueous solution at 40 °C for coagulation molding, and obtain seaweed fibers with a linear density of 1.4 dtex through stretching and rinsing.

[0053] (3) Dissolve 1 g of potassium metaaluminate in water to prepare 1000 g of immersion solution; contact and soak 40 g of the seaweed fibers prepared in step (2) with the immersion solution at 30 °C for 20 minutes. After the soaking is completed, obtain post-treatment crosslinked seaweed fibers through rinsing and drying.

[0054] Example 2

[0055] (1) Dissolve 100 g of sodium alginate in water to prepare 2000 g of solution as the spinning solution.

[0056] (2) Prepare an aqueous solution of 6% calcium chloride + 1.5% sodium metaaluminate by mass percentage as the coagulation bath aqueous solution. After standing and degassing the spinning solution, extrude it into the coagulation bath aqueous solution at 40 °C for coagulation molding, and obtain seaweed fibers with a linear density of 1.4 dtex through stretching and rinsing;

[0057] (3) Dissolve 3 g of sodium metaaluminate and 3 g of potassium metaaluminate in water to prepare 1000 g of immersion solution; contact and soak 100 g of the seaweed fibers prepared in step (2) with the immersion solution at 40 °C for 10 minutes. After the soaking is completed, obtain post-treatment crosslinked seaweed fibers through rinsing and drying. ]

[0058] Example 3

[0059] (1) Dissolve 300 g of sodium alginate in water to prepare 4,000 g of solution as the spinning solution.

[0060] (2) Prepare an aqueous solution of 4.5% calcium chloride by mass percentage as the coagulation bath aqueous solution. After standing and degassing the spinning solution, extrude it into the coagulation bath aqueous solution at 55 °C for coagulation molding, and obtain seaweed fibers with a linear density of 1.4 dtex through stretching and rinsing;

[0061] (3) Dissolve 5 g of barium metaaluminate and 4 g of sodium metaaluminate in water to prepare 6000 g of immersion solution; contact and soak 300 g of the seaweed fibers prepared in step (2) with the immersion solution at 50 °C for 8 minutes. After the soaking is completed, obtain post-treatment crosslinked seaweed fibers through rinsing and drying.

[0062] Comparative Example 1

[0063] ((1) Prepare a 1000 g solution of 40 g of sodium alginate and 1 g of aluminum sulfate as the spinning solution.

[0064] (2) Prepare an aqueous coagulation bath solution of 5% calcium chloride + 1% aluminum sulfate by mass percentage. After the spinning solution is left standing to remove bubbles, it is extruded into the aqueous coagulation bath solution at 40 °C for coagulation molding, and then seaweed fibers with a linear density of 1.4 dtex are obtained through drawing and rinsing.

[0065] (3) Dissolve 1 g of aluminum sulfate in water to prepare 1000 g of soaking solution; contact 40 g of the seaweed fibers prepared in step (2) with the soaking solution at 30 °C for 20 minutes for infiltration. After infiltration, the post-treatment cross-linked seaweed fibers are obtained through rinsing and drying.

[0066] Comparative Example 2

[0067] Refer to Example 1 for preparation, where only the dosage of potassium alum in step (3) is adjusted to 5 g, and others remain unchanged, to prepare cross-linked seaweed fibers.

[0068] Take the seaweed fibers of Examples 1 - 3 and Comparative Examples 1 - 2 for dyeing, and the process is as follows:

[0069] Weigh reactive dyes according to 2% of the mass of seaweed fibers, prepare a dyeing solution according to a bath ratio of 1:30. When the dyeing solution is heated to 30 °C, put the prepared seaweed fibers into the dyeing solution, then heat the dyeing solution at a rate of 2 °C / min to 80 °C, add potassium meta-aluminate at 2 g / L and sodium meta-aluminate at 3 g / L for color fixation, and perform color fixation treatment for 50 minutes. Put the dyed seaweed fibers into a neutral detergent at 5 g / l, perform oscillating treatment at 95 °C for 5 minutes, wash in hot water at 50 °C, and dry in an oven at 60 °C.

[0070] Refer to the national standard "GB / T3921 - 2008 Textiles - Tests for colour fastness - Colour fastness to soaping" to test the wash color fastness of the fibers. The wash color fastness of the seaweed fibers obtained in Examples 1, 2, 3 and Comparative Example 1 to reactive red 3BS, reactive yellow 3RS, and reactive blue 2GLN all reach or exceed level 4.

[0071] The dyeing properties of ordinary seaweed fibers and the dyeable seaweed fibers obtained in Examples 1, 2, 3 and Comparative Examples 1 - 2 are shown in Table 1. It can be seen that in Comparative Example 1 using aluminum sulfate, the dye uptake rate for reactive red 3BS, reactive yellow 3RS, and reactive blue 2GLN is not high and the breaking strength is only half of that of ordinary seaweed fibers, indicating that using aluminum sulfate in water-soluble aluminate does not achieve good results. In Comparative Example 2, the concentration of meta-aluminate in the soaking solution is increased, that is, the ratio of meta-aluminate to seaweed fibers is increased. It can be found that although the dye uptake rate has increased, the decrease in breaking strength has increased from 0.03 cN / dtex to 0.09 cN / dtex. Therefore, the ratio of meta-aluminate to seaweed fibers in the treatment of the soaking solution should not be set too high.

[0072] Table 1 Properties of ordinary and dyeable seaweed fibers

[0073]

[0074] It should be noted that the above embodiments are only used to further illustrate the present invention and should not be construed as limiting the protection scope of the present invention. Those skilled in the art, based on the guidance of the above inventive content, make some non-essential improvements and adjustments to the present invention, which still fall within the protection scope of the present invention.

Claims

1. A method for preparing seaweed fiber dyed with reactive dyes with high dye uptake and minimal fiber damage, characterized in that: The following steps are involved: S1. Preparation of spinning solution: Sodium alginate and a water-soluble aluminate are dissolved in water and mixed uniformly to prepare a sodium alginate spinning solution; the water-soluble aluminate is one or more of potassium aluminum sulfate, potassium metaaluminate, sodium metaaluminate, and barium metaaluminate; the mass ratio of sodium alginate to water-soluble aluminate is 40:0-5g; the concentration of sodium alginate in the sodium alginate spinning solution is 3-7.5wt%; S2. Coagulation and forming of fibers: The spinning solution obtained in step S1 is allowed to stand for degassing and then extruded into a coagulation bath aqueous solution at 40-70° C. for coagulation and forming. After drawing, rinsing, and drying, seaweed fibers containing water-soluble aluminate are obtained; the coagulation bath aqueous solution is a mixture of calcium chloride and water-soluble aluminate; the water-soluble aluminate in the coagulation bath aqueous solution is one or more of potassium aluminum sulfate, potassium metaaluminate, sodium metaaluminate, and barium metaaluminate; the concentration of calcium chloride in the coagulation bath aqueous solution is 4-6 wt %; the concentration of water-soluble aluminate in the coagulation bath aqueous solution is 0-2 wt %; S3, fiber post-treatment: the seaweed fiber obtained in step S2 is brought into contact with the auxiliary agent solution at 20-70° C. and immersed for 5-60 minutes, and after the immersion is completed, the fiber is rinsed and dried to obtain the dyeable seaweed fiber; the auxiliary agent in the auxiliary agent solution is one or more of potassium aluminum sulfate, potassium metaaluminate, sodium metaaluminate, and barium metaaluminate; the auxiliary agent concentration in the auxiliary agent solution is 0.1-0.6 wt%; and the mass ratio of the seaweed fiber to the auxiliary agent in the auxiliary agent solution is 15-40:1; S4. Dyeing: Weighing a reactive dye according to 1-2% of the mass of the dyeable seaweed fiber, preparing a dye solution according to a bath ratio of 1:20-30, waiting for the dye solution to be heated to 30-35° C., adding the dyeable seaweed fiber into the dye solution, then heating the dye solution to 70-80° C. at a rate of 1-2° C. / min, then adding 4-5 g / L of water-soluble aluminate to perform color fixation for 40-50 minutes, then removing the seaweed fiber and adding it to 4-5 g / L of neutral detergent, shaking it at 90-95° C. for 5-10 minutes, and then drying it to obtain the dyed seaweed fiber.

2. The dyed seaweed fiber prepared by the method according to claim 1.

3. Application of the dyed seaweed fiber according to claim 2 in the field of textiles and clothing.

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