A polymer coloring method, spinning solution and colored fiber

Abstract

The invention relates to a polymer coloring method, a spinning solution and a colored fiber, and belongs to the technical field of textile printing and dyeing. The invention solves the problem that the existing dyeing method has a large filtering pressure of the spinneret and a high breakage rate, which leads to low relative strength and elongation at break of the dyed fiber product. The polymer coloring method comprises the following steps: reacting a chromogenic reaction monomer, a first monomer and a second monomer to prepare a polyisophthalamide-metaphenylene diamine colored spinning solution; pre-treating the spinning solution to remove impurities; spinning the pre-treated spinning solution to obtain a spun fiber; and post-treating the spun fiber to obtain a polyisophthalamide-metaphenylene diamine colored fiber. The invention prepares polyisophthalamide-metaphenylene diamine colored fibers by using a chromogenic reaction monomer, thereby improving the filtering performance and spinnability of the spinning solution compared with the prior art, and the obtained fiber product has a durable coloring, good physical properties and low dyeing cost.

Description

Technical Field

[0001] The invention relates to the technical field of textile printing and dyeing, and in particular to a polymer coloring method, spinning solution and colored fiber. Background Art

[0002] Poly(m-phenylene isophthalamide), hereinafter referred to as PMIA, has excellent heat resistance. The decomposition temperature of the fiber made from it reaches 500°C, the long-term use temperature is greater than 230°C, the limiting oxygen index is >29, and it has excellent high temperature acid and alkali resistance, electrical insulation and good textile processing performance. It is widely used in protective clothing, high temperature filter materials, electrical industry and composite materials. It is an important strategic material that cannot be lacking in the country's economic development. However, due to the regular molecular structure, high crystallinity and lack of active functional groups on the molecular chain of PMIA fiber, it is difficult for dye or pigment molecules to penetrate into its structure. The polymerized PMIA fiber molecules are difficult to combine with dye or pigment molecules, which makes it difficult to dye itself and the prepared fabrics, making the application of PMIA fiber in the field of high temperature protection a "short board".

[0003] The existing coloring and dyeing method generally mixes pigments or dyes with fiber natural color slurry (polyisophthalamide solution). Pigments are generally inorganic or insoluble organic matter, which exist in the spinning solution fiber in the form of particles, which are easy to block the micropores of the spinneret, resulting in high filtration pressure and high breakage rate, resulting in low relative strength and elongation at break of the colored fiber products. Dyes are generally small organic molecules that are not heat-resistant and are prone to discoloration and fading during high-temperature treatment and use of fiber products.

[0004] In addition, during wet spinning, since polar solvents and water are miscible with dye molecules, dyes are easily dissolved and carried away by solvents and water washing, resulting in a low exhaustion rate, or even failure to dye. In addition, organic small molecule dyeing usually involves placing fibers, yarns or fabrics in a special solution containing dyes and specific chemical materials. Dye molecules are fixed to fibers by physical bonding, such as absorption, diffusion or bonding, at a certain temperature and pressure. The bonding between dye molecules and fibers depends on the physical bonding force between the dye molecules used and the fibers. For example, PMIA fibers are prone to fading or discoloration due to their weak physical bonding force with dye molecules. In addition, dyeing needs to be carried out in a solvent, which consumes a lot of energy and produces a large amount of wastewater and waste residue. Summary of the invention

[0005] In view of the above analysis, the present invention aims to provide a polymer coloring method, a spinning solution and colored fibers, so as to solve the problems of high filtration pressure of the spinneret, high breakage rate, low relative strength and elongation at break of the dyed fiber products, poor water washing resistance and poor light resistance in the coloring method in the prior art, as well as one of the problems that printing and dyeing produces a large amount of wastewater and waste residue, polluting the environment.

[0006] The purpose of the present invention is mainly achieved through the following technical solutions:

[0007] The invention discloses a polymer coloring method, comprising the following steps:

[0008] Step 1: mixing a chromogenic monomer and a first monomer and then polymerizing them with a second monomer to prepare a poly(m-phenylene isophthalamide) colored spinning solution, wherein the chromogenic monomer and the first monomer react with the second monomer to form an amide bond and are connected to the second monomer via the amide bond;

[0009] Step 2: pre-treating the prepared colored spinning solution to remove impurities;

[0010] Step 3: Spinning the pretreated spinning solution to obtain primary fibers;

[0011] Step 4: Post-treating the spun fibers to obtain poly(m-phenylene isophthalamide) colored fibers.

[0012] Preferably, the step 1 comprises the following steps:

[0013] Step 101: dissolving a chromogenic monomer and a first monomer in a solvent;

[0014] Step 102: adding a second monomer while stirring to polymerize to obtain a poly(m-phenylene isophthalamide) spinning solution.

[0015] Preferably, in step 102, the polymerization reaction temperature is -20°C to 60°C.

[0016] Preferably, the chromophoric reaction monomer is a compound containing two primary amino groups; preferably, the chromophoric reaction monomer is an aromatic compound containing two primary amino groups; preferably, the chromophoric reaction monomer is diaminoanthraquinone or azo aromatic diamine.

[0017] Preferably, the diaminoanthraquinone is one or more of 1,4-diaminoanthraquinone, 1,5-diaminoanthraquinone, 2,6-diaminoanthraquinone, 1,5-diamino-4,8-dihydroxyanthraquinone, 1,2-diaminoanthraquinone, 1,8-diaminoanthraquinone, 1,4-diamino-2,3-diphenyloxyanthraquinone, 1,4-diamino-2,3-dichloroanthraquinone, 1,4-diamino-2-methoxyanthracene-9,10-dione and 1,5-diamino-4,8-dihydroxy-2-chloroanthraquinone, and / or the azo aromatic diamine is 4-[(4-nitrophenyl)azo]benzene-1,3-diamine.

[0018] Preferably, in step 101, the solvent is a polar organic solvent, and the polar organic solvent is any one of N-dimethylacetamide, dimethylformamide, and N-methylpyrrolidone.

[0019] A spinning solution for colored fibers, comprising a colored polymer and a polar organic solvent;

[0020] The colored polymer comprises: The two structural units (Ⅰ) and (Ⅱ) are randomly distributed, and Aq contains an anthraquinone functional group or an aromatic azo group.

[0021] Preferably, the viscosity [η] of the spinning solution is 1.65 to 2.05.

[0022] Preferably, the quantitative ratio of the two structural units (I) and (II) in the colored polymer is 80-99.9:0.1-20.

[0023] A colored fiber, comprising randomly distributed two structural units (I) and (II):

[0024]

[0025] Aq contains anthraquinone functional group or aromatic azo group, and the quantity ratio of the two structural units (Ⅰ) and (Ⅱ) is 80-99.9:0.1-20; the dynamic viscosity is 13000 centipoise to 28000 centipoise.

[0026] Compared with the prior art, the present invention can achieve at least one of the following beneficial effects:

[0027] (1) The coloring method of the present invention is to introduce dye molecules into the main chain of polymers through certain chemical reactions to copolymerize to form colored polymers, which is different from the coloring mechanism of blending and grafting copolymerization. The coloring reaction monomer is one of the reactants, copolymerizes with other monomers of the fiber to form a polymer main chain, dissolves in the solvent system, and forms a homogeneous solution. Compared with the existing fiber coloring method using granular pigments, the filtration pressure is small, the breakage rate is low, and the relative strength and elongation at break of the dyed fiber are high, which greatly improves the physical properties of the colored fiber products; improves the defects of the prior art that the micropores of the spinneret are easily blocked, the filtration pressure is large, the breakage rate is high, and the relative strength and elongation at break of the dyed fiber products are low; compared with the method of dyeing the fiber after spinning, the coloring unit structure of the present invention is more stable and not easy to be leached, lost or aged, and the dyeing durability and light aging resistance are significantly improved.

[0028] (2) The present invention obtains a rich color system by selecting chromogenic monomers with different reactivities to copolymerize with other monomers of the polymer to be dyed to form a polymer chain; while the co-blending coloring method in the prior art needs to consider the dispersion and uniformity of the pigment and the compatibility of the pigment with the polymer, which limits the range of pigment selection.

[0029] (3) The present invention forms a polymer chain through the polymerization of chromogenic monomers, which are dispersed in the resin matrix at the molecular level. The dispersion is uniform, the tinting power is strong, and the amount of monomer used is very small, which can save the dyeing cost. The existing blended coloring adjusts the color and depth of the dyeing by the amount of pigment added. The pigment exists in the polymer in the form of particles, has poor tinting power, and requires a large amount of addition.

[0030] (4) The polar solvent used in the spinning process of the present invention can be recovered by vacuum distillation and the like, and there is no printing and dyeing waste residue and waste water generated in the dyeing process of the prior art. Compared with the existing spinning method, energy saving and consumption reduction are achieved, and environmental pollution is reduced.

[0031] In the present invention, the above-mentioned technical solutions can also be combined with each other to achieve more preferred combination solutions. Other features and advantages of the present invention will be described in the subsequent description, and some advantages can be obvious from the description or understood by practicing the present invention. BRIEF DESCRIPTION OF THE DRAWINGS

[0032] The drawings are only for the purpose of illustrating particular embodiments and are not to be considered limiting of the present invention. Like reference symbols denote like components throughout the drawings.

[0033] Figure 1 This is a process flow chart of the one-step full-quantity method of the present invention. DETAILED DESCRIPTION

[0034] The preferred embodiments of the present invention will be described in detail below in conjunction with the accompanying drawings, wherein the accompanying drawings constitute a part of the present invention and are used together with the embodiments of the present invention to illustrate the principles of the present invention, but are not used to limit the scope of the present invention.

[0035] A specific embodiment of the present invention discloses a polymer coloring method, comprising the following steps:

[0036] Step 1: mixing a chromogenic monomer and a first monomer and then polymerizing them with a second monomer to prepare a poly(m-phenylene isophthalamide) colored spinning solution, wherein the chromogenic monomer and the first monomer respectively form an amide bond with the second monomer and are connected to the second monomer through the amide bond;

[0037] Step 2: pre-treating the prepared PMIA colored spinning solution into a slurry before spinning;

[0038] Step 3: wet spinning and precipitation of the PMIA colored spinning solution treated in step 2 to obtain primary fibers;

[0039] Step 4: The spun fibers obtained in step 3 are post-treated to obtain PMIA colored fibers.

[0040] It should be noted that the present invention introduces dye molecules into the main chain of the polymer through chemical reaction to copolymerize to form a colored polymer, which is different from the coloring mechanism of blending and grafting copolymerization: the chromogenic reaction monomer is one of the reactants, copolymerizes with other monomers of the synthetic fiber (such as the first monomer or the second monomer) to form a polymer main chain, and is dissolved in the solvent system to form a homogeneous solution.

[0041] Compared with the fiber coloring method in the prior art using granular pigments, the coloring method of the present invention has the characteristics of low filtration pressure, low breakage rate, high relative strength and elongation at break of the dyed fiber, which greatly improves the physical properties of the colored fiber products; it improves the defects of the prior art that the micropores of the spinneret are easily blocked, the filtration pressure is large, the breakage rate is high, and the relative strength and elongation at break of the dyed fiber products are low; at the same time, since the coloring unit is directly involved in the formation of the coloring polymer, the coloring unit structure of the present invention is more stable than dyeing, is not easy to leach or age, and the dyeing durability and light aging resistance are significantly improved.

[0042] It is understandable that the present invention uses chromogenic monomers as reactive monomers for coloring PMIA fibers, connects them to the PMIA polymer main chain during the reaction, prepares spinning paste, and then realizes the PMIA spinning process to directly prepare colored fibers. These fibers can be easily processed into colored yarns and further made into colored fabrics; or directly used to prepare non-woven fabrics, and no dyeing is required during the subsequent use of the fibers. In contrast, if PMIA natural color paste is used for spinning to obtain fibers, and then they are colored after spinning or weaving, an additional dyeing process is required, and the bath used in the dyeing process also needs to be treated before it can be discharged. Compared with the prior art, the present invention does not generate dyeing wastewater, and reduces the discharge of wastewater after water treatment.

[0043] Specifically, the polymerization reaction temperature of the polymerization reaction in step 1 is -20°C to 60°C; for example, it can be -20°C, -15°C, -10°C, -5°C, 0°C, 5°C, 10°C, 15°C, 20°C, 25°C, 30°C, 35°C, 40°C, 45°C, 50°C, 55°C, or 60°C.

[0044] It should be noted that when the polymerization reaction temperature is lower than -20°C, the reaction rate is low, which will reduce the efficiency of the entire process and prolong the reaction time; when the polymerization reaction temperature is higher than 60°C, the side reactions increase, the linearity of PMIA molecules is destroyed, the molecular weight is lower, the viscosity is lower, the spinnability decreases, and the fiber strength and elongation at break decrease.

[0045] Specifically, the preparation of the colored spinning solution of poly(m-phenylene isophthalamide) (PMIA) in step 1 can be carried out by a one-step full polymerization method:

[0046] Specifically, Figure 1 As shown, the one-step full polymerization method is to directly polymerize the chromogenic reaction monomer with the first monomer and the second monomer according to the complete reaction stoichiometry or close to the complete reaction stoichiometry to form the PMIA colored spinning solution.

[0047] It should be noted that when the second monomer is sufficient or excessive, the first monomer and the chromogenic monomer undergo a competitive reaction and can both react with the second monomer, and the prepared colored polymer long chain has both the first monomer-second monomer structural unit and the chromogenic monomer-second monomer structural unit.

[0048] Specifically, the first monomer includes an amino group, and the second monomer includes a formyl group.

[0049] Preferably, the first monomer is m-phenylenediamine and the second monomer is isophthaloyl chloride.

[0050] Specifically, the chromophoric reaction monomer is a compound containing two primary amino groups.

[0051] Preferably, the chromophoric reactive monomer is an aromatic compound containing two primary amino groups.

[0052] Preferably, the chromogenic monomer is diaminoanthraquinone or azo aromatic diamine.

[0053] Preferably, the color-forming reaction monomer can be selected from one or more of 1,4-diaminoanthraquinone, 1,5-diaminoanthraquinone, 2,6-diaminoanthraquinone, 1,5-diamino-4,8-dihydroxyanthraquinone, 1,2-diaminoanthraquinone, 1,8-diaminoanthraquinone, 1,4-diamino-2,3-diphenyloxyanthraquinone, 1,4-diamino-2,3-dichloroanthraquinone, 1,4-diamino-2-methoxyanthracene-9,10-dione, and 1,5-diamino-4,8-dihydroxy-2-chloroanthraquinone.

[0054] Specifically, the structural formula of 1,4-diamino-2,3-diphenoxyanthraquinone satisfies:

[0055]

[0056] The structural formula of 1,4-diamino-2,3-dichloroanthraquinone satisfies:

[0057]

[0058] The structural formula of 1,4-diamino-2-methoxyanthracene-9,10-dione satisfies:

[0059]

[0060] The structural formula of 1,5-diamino-4,8-dihydroxy-2-chloroanthraquinone satisfies:

[0061]

[0062] Preferably, the chromogenic monomer may be an azodiamine such as 4-[(4-nitrophenyl)azo]benzene-1,3-diamine.

[0063] Specifically, the structural formula of 4-[(4-nitrophenyl)azo]benzene-1,3-diamine satisfies:

[0064]

[0065] For example, taking m-phenylenediamine as the first monomer and isophthaloyl chloride as the second monomer and the second monomer being sufficient or excessive, the reaction formula of the first monomer and the second monomer is as follows:

[0066]

[0067] Where n represents the number of polymer constituent units; It represents a polymer constituent unit formed by the reaction of a first monomer and a second monomer.

[0068] For example, taking diaminoanthraquinone (general formula NH2-Aq-NH2) as the chromogenic reaction monomer and isophthaloyl chloride as the second monomer and the second monomer being sufficient or excessive, the chromogenic reaction monomer, the first monomer and the second monomer react as follows:

[0069]

[0070] in, represents the polymer component unit formed by the reaction of the chromogenic monomer and the second monomer, a represents the number of polymer structural units formed by the reaction of diaminoanthraquinone, na represents the number of polymer structural units formed by the reaction of m-phenylenediamine, and Aq contains anthraquinone functional groups or aromatic azo groups; the two structural units (Ⅰ) and (Ⅱ) are randomly distributed in the colored fiber:

[0071] Specifically, the quantitative ratio of the two structural units (Ⅰ) and (Ⅱ) is 80-99.9:0.1-20.

[0072] Specifically, the preparation of the poly(m-phenylene isophthalamide) (PMIA) colored spinning solution in step 1 comprises the following steps:

[0073] S101: dissolving a chromogenic monomer and a first monomer for preparing poly(m-phenylene isophthalamide) in a polar organic solvent;

[0074] S102: gradually adding a second monomer for preparing poly(meta-phenylene isophthalamide) while stirring, performing a polymerization reaction, and obtaining a colored spinning solution of poly(meta-phenylene isophthalamide) (PMIA).

[0075] Specifically, in step S102, the polymerization reaction for preparing the poly(m-phenylene isophthalamide) colored spinning solution includes a plurality of different reaction stages, and the polymerization reaction temperature of each reaction stage is different:

[0076] The first stage: This stage mainly involves the reaction of the first monomer, the chromogenic monomer and the second monomer to generate a small molecule prepolymer and the random copolymerization of the small molecule prepolymer to generate a long chain prepolymer;

[0077] The second stage: as the second monomer continues to be added, the second monomer reacts with the first monomer or the end group of the chromophoric reaction monomer of the prepolymer molecule to achieve long-chain prepolymer connection and long-chain growth.

[0078] Specifically, taking the second monomer as isophthaloyl chloride as an example, the main reaction equation of the first stage satisfies:

[0079]

[0080] Wherein, R represents the first monomer or the part of the reaction chromogenic unit excluding the amino group; NH2-R-NH2 represents the first monomer or the reaction chromogenic unit; m represents the number of polyisophthaloyl structures in the long-chain prepolymer or the number of the second monomer consumed in the first stage.

[0081] Specifically, taking isophthaloyl chloride as the second monomer as an example, the main reaction equation of the second stage satisfies:

[0082]

[0083] Where n represents the number of polymer structural units in poly(m-phenylene isophthalamide); p represents the number of second monomers consumed in the second stage to prepare PMIA molecules with n structural units; R p+1 represents the p+1th long-chain prepolymer, and the number of polyisophthaloyl structures in different long-chain prepolymers may be the same or different.

[0084] Preferably, the polymerization reaction temperature in the first stage is -20°C to 20°C, within which PMIA molecules have a larger viscosity-average molecular weight and better mechanical strength; the reaction time is 0.05h to 1h.

[0085] More preferably, the polymerization reaction temperature in the first stage is -5°C to 20°C.

[0086] Preferably, the second stage polymerization reaction temperature is 20° C. to 50° C., and the reaction time is 0.05 h to 2 h.

[0087] It should be noted that the second monomer (such as isophthaloyl chloride) is gradually added to the color-forming reaction monomer and the first monomer solution to form a large excess of the color-forming reaction monomer and the first monomer, which is beneficial to the main reaction, inhibits the reaction of a small amount of impurities such as water in the system with the second monomer, reduces the occurrence of side reactions, and is beneficial to the chain extension growth of the prepolymer in the spinning solution to obtain a colored polymer with a larger molecular weight and degree of polymerization.

[0088] It is understandable that gradually adding the second monomer can make it easier to keep the reaction temperature stable and prevent the temperature from getting out of control due to violent heat release from the reaction. At the same time, a lower temperature helps to reduce side reactions.

[0089] Specifically, gradual joining is achieved through the following methods:

[0090] The total amount of the second monomer can be divided into several equal or unequal portions, and a certain amount of the second monomer can be added at a time interval, or, using a continuous feeding device, the feeding rate can be varied from 0 to any value that satisfies instantaneous feeding.

[0091] Specifically, the addition time of the second monomer is 0.1h to 4h, and the polymerization reaction time is 0.1h to 6h; if the time is less than 0.1h, the reaction is incomplete; if the time exceeds 6h, the side reactions increase, which will affect the molecular weight of the polymer and the efficiency is not high.

[0092] Preferably, the polymerization reaction temperature is monitored, and the feed rate is adjusted according to the polymerization reaction temperature to ensure that the polymerization reaction temperature does not exceed a set temperature range.

[0093] Further preferably, when monitoring the polymerization reaction temperature, a temperature control feedback mechanism is provided for the continuous feeding device to ensure that the feeding rate is automatically adjusted according to the temperature so that the polymerization reaction temperature is automatically added within a controllable range.

[0094] Specifically, when the temperature is higher than the preset target temperature, the feed is reduced or stopped, and the heat dissipation rate of the heat dissipation device on the reactor is increased (for example, the cooling water temperature is lowered and the water flow rate is increased); when the temperature is lower than the preset target temperature, the feed rate is increased, the heat dissipation rate of the heat dissipation device on the reactor is reduced, and the heating device is turned on for heating when necessary, thereby realizing the use of temperature feedback to regulate the feed amount.

[0095] Specifically, the amount ratio of the chromogenic reaction monomer in the chromogenic reaction monomer and the first monomer is in the range of 0.1% to 20%.

[0096] It should be noted that when the molar ratio of the chromogenic monomer in the chromogenic monomer and the first monomer is greater than 20%, the molecular weight and degree of polymerization of the colored polymer in the spinning solution decrease, and the spinnability decreases.

[0097] Specifically, the polar organic solvent in step S101 can be any one of N-dimethylacetamide, dimethylformamide (DMF), and N-methylpyrrolidone, which has good solubility for the raw material monomers in the range of -20°C to 60°C and does not react with any raw material monomers.

[0098] Specifically, in step S102, the mass concentration of PMIA in the poly(meta-phenylene isophthalamide) spinning solution is 16-24%.

[0099] Regarding the color development effect of the spinning solution and the spinning process, it should be noted that, on the one hand, the chromogenic monomers participating in the reaction make the PMIA colored spinning solution and the PMIA colored fiber after spinning present the color of the corresponding chromogenic monomer; on the other hand, by selecting a variety of chromogenic monomers of different colors for compounding, a mixed color different from any single chromogenic monomer can be produced after spinning.

[0100] Specifically, various types of reactors can be used to obtain the colored spinning solution of poly(metaphenylene isophthalamide) (PMIA), all of which have strong material mixing functions, such as vertical or horizontal kettle reactors, screw reactors, and kneaders; the length-to-diameter ratio of the reactor is mostly greater than 1:1, and it is equipped with a jacket for passing cooling liquid or heating liquid or other forms of heat dissipation equipment or heating devices.

[0101] Specifically, the stirring power of the vertical or horizontal kettle reactor is 3KW / cubic to 50KW / cubic, the stirring speed is 100rpm-3000rpm, and there are many types of stirring paddles available, such as anchor type, paddle type, frame type, multi-layer paddle type, cross type or their composite structure type stirring paddles.

[0102] Specifically, a screw reactor and various mixing and kneading structural units are used in combination to maintain a rapid tumbling state of the solution during the reaction, achieve good internal and external heat exchange, and realize rapid polymerization while ensuring safety conditions.

[0103] It should be noted that, on the one hand, the radial flow rate brought by stirring is required to meet the requirement that when the second monomer is added, the materials in different radial regions inside the reaction vessel are evenly mixed, that is, radial mass transfer is realized; on the other hand, the axial flow rate brought by stirring can meet the requirement that when the second monomer is added, the materials in different axial regions inside the reaction vessel are evenly mixed, that is, axial mass transfer is realized; in addition, while achieving mixing of various regions, the heat in the internal region of the reaction container is transferred to the heat exchange region with the outside world, and heat is exchanged with the outside world, thereby realizing heat transfer in various regions inside the reactor and stable temperature control.

[0104] Specifically, the pretreatment of the spinning slurry in step 2 includes: neutralization, filtration and degassing.

[0105] Specifically, the neutralizing agent is selected from: any one of inorganic base and organic amine.

[0106] Preferably, the inorganic base is one or more of calcium oxide, calcium hydroxide, sodium hydroxide, lithium hydroxide and liquid ammonia.

[0107] Specifically, the organic amine is one or more of diethylamine, triethylamine, and tetraethylethylenediamine.

[0108] Specifically, the colored polymer in the colored spinning solution prepared by the present invention has good solubility and good fluidity during filtration, and the filtration pressure is 0.3Mpa to 0.5Mpa.

[0109] Specifically, the filtration uses closed filters such as plate and frame filter presses, candle filter element filters, disc filters, chamber filters and other precision pressure-resistant filters.

[0110] It can be understood that the filtration pressure is related to the spinning solution density, filtration speed and the content of insoluble impurities in the solution. In the prior art, inorganic dyes are insoluble in the spinning solution and are prone to agglomeration during filtration, which increases the filtration pressure and energy consumption of the filtration pump.

[0111] Specifically, the degassing is performed by vacuum degassing, and the vacuum degree is 0.1-20 KPa.

[0112] Specifically, the spinning pressure of the wet spinning in step 3 is set to 0.2MPa to 2MPa, for example, 0.2MPa, 0.4MPa, 0.5MPa, 0.6MPa, 0.8MPa, 1.0MPa, 1.2MPa, 1.4MPa, 1.5MPa, 1.6MPa, 1.8MPa, 2.0MPa; the spinning temperature is 5°C to 40°C, for example, 5°C, 6°C, 8°C, 10°C, 12°C, 14°C, 15 ℃, 18℃, 20℃, 22℃, 24℃, 25℃, 28℃, 30℃, 32℃, 35℃, 38℃, 40℃; the spinning feed rate is 1 m / min to 30 m / min, for example, 1 m / min, 2 m / min, 5 m / min, 8 m / min, 10 m / min, 12 m / min, 15 m / min, 18 m / min, 20 m / min, 22 m / min, 25 m / min, 28 m / min, 30 m / min.

[0113] Specifically, the hole diameter of the wet spinning spinneret is 0.04 mm to 0.10 mm, for example, 0.04 mm, 0.06 mm, 0.08 mm, or 0.10 mm.

[0114] Specifically, the precipitation solution used in step 3 is a mixture of the above-mentioned polar organic solvent and an aqueous solution of alcohol and / or calcium chloride.

[0115] In the solution composed of PMIA fiber and polar organic solvent, the addition of alcohol or calcium chloride helps to reduce the solubility of PMIA fiber in the mixed solution.

[0116] Specifically, the mass ratio of the polar organic solvent to the aqueous solution of alcohol and / or calcium chloride is in the range of 0.2-0.7:0.3-0.8, within which the spinning precipitate has the highest yield.

[0117] Specifically, the post-processing in step 4 includes: plasticizing and stretching, water washing, drying and high-temperature heat treatment.

[0118] Specifically, the specific method and process conditions of plasticizing and stretching are: the fiber passes through a plurality of rollers with different speeds in sequence, so that the speed of the fiber when leaving the stretching machine is greater than the speed when entering the stretching machine, thereby achieving the stretching effect.

[0119] Specifically, the fibers are immersed in the plasticizing liquid or washed by the plasticizing liquid in two multi-roll machines at different speeds.

[0120] Specifically, the plasticizing liquid is a mixture of polar solvent, inorganic salt and water.

[0121] Preferably, the plasticizing liquid is an aqueous solution of DMAC (dimethylacetamide) and calcium chloride, and the mass ratio satisfies: DMAC: calcium chloride: water = (5-30): (0-20): (70:50).

[0122] It can be understood that the effect of plasticization and stretching is: the fiber is affected by the plasticizing liquid, and the polymer is affected by the solvent, so it swells to a certain extent. Under the action of external force, the polymer can slide against each other to a certain extent, so as to achieve the purpose of stretching the molecules in the fiber along the axial orientation of the fiber.

[0123] Specifically, during the plasticization and stretching process, the fibers absorb the plasticizing liquid, and thus polar solvents, inorganic salts and other substances in the plasticizing liquid remain. The presence of these substances affects the physical and mechanical properties of the fibers. Water washing is used to remove impurities, recover solvents, and reduce material consumption. Specific methods of water washing include: using multi-stage water washing, and washing the fibers by multi-stage countercurrent immersion or elution.

[0124] Specifically, the specific method and process conditions of drying are: drying the fiber bundle by means of multi-stage hot rollers, hot plates or hot cavities, etc. When the fibers pass through the surface of the above-mentioned thermal equipment, the heat is transferred from the machine to the fibers, the temperature of the fiber bundle rises, and the moisture in the fiber bundle evaporates due to the heat, thereby achieving a drying effect; equipment such as hot rollers or hot plates can be heated by means of electric thermal resistors or heat media (such as thermal oil) or steam.

[0125] It is understood that drying can remove residual moisture and polar organic solvents.

[0126] Specifically, the specific method of high-temperature heat treatment in post-processing includes: heating the dried fiber through a high-temperature hot chamber device and stretching it at the same time.

[0127] It can be understood that the effect of high temperature heat treatment is to further orient the polymer in the fiber along the fiber axis, further improve the physical and mechanical properties, and at the same time improve the heat resistance of the fiber after coloring.

[0128] A specific embodiment of the present invention discloses a spinning solution for colored fibers, including a colored polymer and a polar organic solvent, for spinning to prepare the colored fibers;

[0129] The colored polymer comprises: and The two structural units (Ⅰ) and (Ⅱ) are randomly distributed, and Aq contains an anthraquinone functional group or an aromatic azo group.

[0130] Preferably, the mass concentration of PMIA in the spinning solution is 16-24%.

[0131] Preferably, the viscosity [η] of the spinning solution is 1.65 to 2.05.

[0132] [η] represents the relative viscosity, which is the ratio of the dynamic viscosity of the spinning solution to the dynamic viscosity of the solvent in the spinning solution.

[0133] Specifically, the quantitative ratio of the two structural units (Ⅰ) and (Ⅱ) is 80-99.9:0.1-20.

[0134] Specifically, the polar organic solvent may be any one of N-dimethylacetamide, dimethylformamide (DMF), and N-methylpyrrolidone.

[0135] A specific embodiment of the present invention discloses a colored fiber, wherein the colored fiber comprises randomly distributed two structural units (I) and (II):

[0136]

[0137]

[0138] Aq contains anthraquinone functional group or aromatic azo group, and the quantity ratio of the two structural units (Ⅰ) and (Ⅱ) is 80-99.9:0.1-20.

[0139] Optionally, the colored fiber is prepared by the above-mentioned polymer coloring method.

[0140] Specifically, a PMIA colored spinning solution is prepared by reacting a chromogenic monomer, a first monomer and a second monomer, and the colored spinning solution is further spun to obtain colored fibers.

[0141] Specifically, the first monomer includes an amino group, and the second monomer includes a formyl group.

[0142] Preferably, the first monomer is m-phenylenediamine and the second monomer is isophthaloyl chloride.

[0143] Specifically, the chromophoric reaction monomer is a compound containing two primary amino groups.

[0144] Preferably, the chromophoric reactive monomer is an aromatic compound containing two primary amino groups.

[0145] Preferably, the chromogenic monomer is diaminoanthraquinone. For example, one or more of 1,4-diaminoanthraquinone, 1,5-diaminoanthraquinone, 2,6-diaminoanthraquinone, 1,5-diamino-4,8-dihydroxyanthraquinone, 1,2-diaminoanthraquinone, 1,8-diaminoanthraquinone, 1,4-diamino-2,3-diphenyloxyanthraquinone, 1,4-diamino-2,3-dichloroanthraquinone, 1,4-diamino-2-methoxyanthracene-9,10-dione, 1,5-diamino-4,8-dihydroxy-2-chloroanthraquinone can be selected.

[0146] Preferably, the chromogenic monomer may be an azodiamine such as 4-[(4-nitrophenyl)azo]benzene-1,3-diamine.

[0147] Specifically, the dynamic viscosity of the fiber is 13000-28000 / centipoise; the glass transition temperature of the colored fiber is 230-280°C; the relative strength of the fiber is 3.95-4.3 cN / dtex; the elongation at break of the fiber is 16.8%-30%; the color fastness to light is grade 3-5; and the color fastness to washing is grade 4-5.

[0148] In order to better illustrate the present invention, the following embodiments and comparative examples are further provided:

[0149] Example 1

[0150] (1) Preparation of colored spinning solution: 1,4-diaminoanthraquinone and meta-phenylenediamine are added to an appropriate amount of N-dimethylacetamide solvent at a molar ratio of 0.5:99.5, and isophthaloyl chloride is gradually added to the above solution in an equal amount within 2 hours according to the reaction stoichiometric ratio for gradual polymerization; meta-phenylenediamine and diaminoanthraquinone are directly polymerized with isophthaloyl chloride in an equal amount or nearly equal amount in one step to form PMIA colored spinning solution (solute mass concentration of 16.7%), and the feed amount is adjusted by temperature feedback to control the polymerization reaction temperature and time at -5°C for 1 hour in the first stage and at 20°C for 1 hour in the second stage.

[0151] (2) The prepared PMIA colored spinning solution was neutralized with calcium hydroxide, filtered, and degassed at a filtration pressure of 0.4 MPa. Then, the spinning pressure or the pressure in each spinning area was 0.6 MPa, the spinning temperature was 25°C, and the spinning feed rate was 6 m / min. Wet spinning and precipitation were performed to obtain primary fibers. The spinning process was smooth and there was basically no hair. The aperture of the spinning spinneret was 0.06 mm, and the precipitation solution was a mixture of N-dimethylacetamide, calcium chloride and water (the mass ratio of each component was 45:25:30).

[0152] (3) The spun fibers were subjected to 2-fold plasticization stretching, water washing, 120°C drying, and 360°C high-temperature heat treatment to directly obtain the corresponding PMIA colored fibers.

[0153] Example 2

[0154] (1) 1,5-diaminoanthraquinone and meta-phenylenediamine are added to an appropriate amount of N-dimethylacetamide solvent in a molar ratio of 0.5:99.5, and an equal amount of isophthaloyl chloride is gradually added to the above solution within 4 hours according to the reaction stoichiometric ratio for gradual polymerization; meta-phenylenediamine and diaminoanthraquinone react with an equal amount or nearly equal amount of isophthaloyl chloride in a one-step reaction to directly polymerize into PMIA colored spinning solution (solute mass concentration of 18%), and the feed amount is adjusted by temperature feedback to control the polymerization reaction temperature and time at -20°C for 2 hours in the first stage and at 50°C for 2 hours in the second stage.

[0155] (2) The prepared PMIA colored spinning solution was neutralized with calcium hydroxide, filtered, and degassed at a filtration pressure of 0.45 MPa. Then, wet spinning was performed at a spinning pressure or a pressure in each spinning area of ​​0.5 MPa, a spinning temperature of 25° C., and a spinning feed rate of 6 m / min. The nascent fibers were precipitated and the spinning process was smooth and substantially free of hair. The aperture of the spinning spinneret was 0.04 mm, and the coagulation bath was an N-dimethylacetamide solution having a mass percentage concentration of 40% and a temperature of 30° C.

[0156] (3) The spun fibers were subjected to 4-fold plasticization stretching, water washing, 120°C drying, and 360°C high-temperature heat treatment to directly obtain the corresponding PMIA colored fibers.

[0157] Example 3

[0158] (1) 2,6-diaminoanthraquinone and meta-phenylenediamine are added to 1067 ml of N-dimethylacetamide solvent in a molar ratio of 0.5:99.5, and isophthaloyl chloride of equal amount is gradually added to the above solution within 2 hours according to the reaction stoichiometric ratio for gradual polymerization; meta-phenylenediamine and diaminoanthraquinone are directly polymerized into PMIA colored spinning solution (solute mass concentration of 16.7%) by one-step reaction with isophthaloyl chloride of equal amount or nearly equal amount, and the feed amount is adjusted by temperature feedback to control the polymerization reaction temperature and time at -5°C for 1 hour in the first stage and at 30°C for 1 hour in the second stage.

[0159] (2) The prepared PMIA colored spinning solution was neutralized with calcium hydroxide, filtered, and degassed at a filtration pressure of 0.38 MPa, and then wet-spun at a spinning pressure or a pressure in each spinning area of ​​0.5 MPa, a spinning temperature of 25°C, and a spinning feed rate of 6 m / min. The spinning process was smooth without hair and precipitation, and the primary fiber was obtained. The aperture of the spinning spinneret was 0.10 mm, and the precipitate was a mixed solution containing N-dimethylacetamide and water in a mass ratio of 60:40.

[0160] (3) The spun fibers were subjected to 4-fold plasticization stretching, water washing, 120°C drying, and 360°C high-temperature heat treatment to directly obtain the corresponding PMIA colored fibers.

[0161] Example 4

[0162] (1) Preparation of colored spinning solution: 1,5-diamino-4,8-dihydroxyanthraquinone and meta-phenylenediamine are added to an appropriate amount of N-dimethylacetamide solvent in a molar ratio of 0.5:99.5, and isophthaloyl chloride is gradually added to the above solution in an equal amount within 2 hours according to the reaction stoichiometric ratio for gradual polymerization; meta-phenylenediamine and diaminoanthraquinone are directly polymerized into PMIA colored spinning solution (solute mass concentration of 16.7%) by a one-step reaction with an equal amount or nearly equal amount of isophthaloyl chloride. In the first stage, the polymerization reaction temperature and time are controlled at -5°C for 1 hour, and in the second stage, the polymerization reaction temperature and time are controlled at 20°C for 1 hour.

[0163] (2) The prepared PMIA colored spinning solution was neutralized and filtered with calcium hydroxide, the filtering pressure was 0.48 MPa, and deaeration was performed, and then wet spinning was performed at a spinning pressure or a pressure in each spinning area of ​​0.65 MPa, a spinning temperature of 26°C, and a spinning feed rate of 5.5 m / min. The spinning process was smooth with basically no hair and precipitation, and the primary fiber was obtained. Among them, the aperture of the spinning spinneret was 0.06 mm, and the precipitate was a mixture of N-dimethylacetamide, calcium chloride and water (the mass ratio of each component was 45:30:25).

[0164] (3) The spun fibers were subjected to 4-fold plasticization stretching, water washing, 120°C drying, and 360°C high-temperature heat treatment to directly obtain the corresponding PMIA colored fibers.

[0165] Example 5

[0166] (1) Preparation of colored spinning solution: 1,4-diaminoanthraquinone and meta-phenylenediamine are added to an appropriate amount of N-dimethylacetamide solvent in a molar ratio of 20:80, and isophthaloyl chloride is gradually added to the above solution in an equal amount within 2 hours according to the reaction stoichiometric ratio for gradual polymerization; meta-phenylenediamine and diaminoanthraquinone are directly polymerized into PMIA colored spinning solution (solute mass concentration of 16.7%) by a one-step reaction with an equal amount or nearly equal amount of isophthaloyl chloride. In the first stage, the polymerization reaction temperature and time are controlled at -5°C for 1 hour, and in the second stage, the reaction temperature and time are controlled at 20°C for 1 hour.

[0167] (2) The prepared PMIA colored spinning solution was neutralized and filtered with calcium hydroxide, the filtering pressure was 0.4 MPa, deaeration was performed, and then wet spinning was performed at a spinning pressure or a pressure in each spinning area of ​​0.70 MPa, a spinning temperature of 25°C, and a spinning feed rate of 6 m / min. The spinning process was smooth with basically no hair and precipitation, and the primary fiber was obtained. The aperture of the spinning spinneret was 0.06 mm, and the precipitate was a mixture of N-dimethylacetamide, calcium chloride and water (the mass ratio of each component was 45:30:25).

[0168] (3) The spun fibers were subjected to 4-fold plasticization stretching, water washing, 120°C drying, and 365°C high-temperature heat treatment to directly obtain the corresponding PMIA colored fibers.

[0169] Example 6

[0170] (1) Preparation of colored spinning solution: 1,4-diaminoanthraquinone and meta-phenylenediamine are added to an appropriate amount of N-dimethylacetamide solvent at a molar ratio of 0.1:99.9, and isophthaloyl chloride is gradually added to the above solution in an equal amount within 2 hours according to the reaction stoichiometric ratio for gradual polymerization; meta-phenylenediamine and diaminoanthraquinone are directly polymerized into PMIA colored spinning solution (solute mass concentration of 16.7%) by a one-step reaction with an equal amount or nearly equal amount of isophthaloyl chloride. In the first stage, the polymerization reaction temperature and time are controlled at 0°C for 1 hour, and in the second stage, the polymerization reaction temperature and time are controlled at 20°C for 1 hour.

[0171] (2) The prepared PMIA colored spinning solution is neutralized with calcium hydroxide, filtered at a filtration pressure of 0.5 MPa, degassed, and then wet-spun at a spinning pressure or a pressure in each spinning area of ​​0.80 MPa, a spinning temperature of 25° C., and a spinning feed rate of 7 m / min, and precipitated to obtain nascent fibers, wherein there is substantially no fuzz during the spinning process. The aperture of the spinning spinneret is 0.06 mm, and the precipitate is a mixture of N-dimethylacetamide and water (N-dimethylacetamide mass ratio 60%).

[0172] (3) The spun fibers are plasticized, stretched, washed, dried and subjected to high-temperature heat treatment to directly obtain the corresponding PMIA colored fibers; wherein the heat stretching temperature is 280° C. and the heat stretching multiple is 2.5 times.

[0173] Example 7

[0174] The preparation method of PMIA colored fiber is the same as that in Example 1, the only difference is that the 1,4-diaminoanthraquinone luminescent coloring monomer in Example 1 is replaced by 1,4-diaminoanthraquinone and 2,6-diaminoanthraquinone in a molar ratio of 1:1.

[0175] Example 8

[0176] (1) Preparation of colored spinning solution: 1,4-diamino-2,3-diphenoxyanthraquinone and meta-phenylenediamine were added to an appropriate amount of N-dimethylacetamide solvent at a molar ratio of 0.5:99.5, and an equal amount of isophthaloyl chloride was gradually added to the above solution within 2 hours according to the reaction stoichiometric ratio for gradual polymerization; meta-phenylenediamine and diaminoanthraquinone were directly polymerized with an equal amount or nearly equal amount of isophthaloyl chloride to form PMIA colored spinning solution (solute mass concentration of 16.7%) in one step, and the feed amount was adjusted by temperature feedback to control the polymerization reaction temperature and time at -5°C for 1 hour in the first stage and at 20°C for 1 hour in the second stage.

[0177] (2) The prepared PMIA colored spinning solution was neutralized with calcium hydroxide, filtered, and degassed at a filtration pressure of 0.4 MPa. Then, the spinning pressure or the pressure in each spinning area was 0.6 MPa, the spinning temperature was 25°C, and the spinning feed rate was 6 m / min. Wet spinning and precipitation were performed to obtain primary fibers. The spinning process was smooth and there was basically no hair. The aperture of the spinning spinneret was 0.06 mm, and the precipitation solution was a mixture of N-dimethylacetamide, calcium chloride and water (the mass ratio of each component was 45:25:30).

[0178] (3) The spun fibers were subjected to 2-fold plasticization stretching, water washing, 120°C drying, and 360°C high-temperature heat treatment to directly obtain the corresponding PMIA colored fibers.

[0179] Example 9

[0180] (1) Preparation of colored spinning solution: 1,4-diamino-2,3-dichloroanthraquinone and meta-phenylenediamine are added to an appropriate amount of N-dimethylacetamide solvent in a molar ratio of 0.5:99.5, and isophthaloyl chloride is gradually added to the above solution in an equal amount within 2 hours according to the reaction stoichiometric ratio for gradual polymerization; meta-phenylenediamine and diaminoanthraquinone are directly polymerized with isophthaloyl chloride in an equal amount or nearly equal amount in one step to form PMIA colored spinning solution (solute mass concentration of 16.7%), and the feed amount is adjusted by temperature feedback to control the polymerization reaction temperature and time at -5°C for 1 hour in the first stage and at 20°C for 1 hour in the second stage.

[0181] (2) The prepared PMIA colored spinning solution was neutralized with calcium hydroxide, filtered, and degassed at a filtration pressure of 0.4 MPa. Then, the spinning pressure or the pressure in each spinning area was 0.6 MPa, the spinning temperature was 25°C, and the spinning feed rate was 6 m / min. Wet spinning and precipitation were performed to obtain primary fibers. The spinning process was smooth and there was basically no hair. The aperture of the spinning spinneret was 0.06 mm, and the precipitation solution was a mixture of N-dimethylacetamide, calcium chloride and water (the mass ratio of each component was 45:25:30).

[0182] (3) The spun fibers were subjected to 2-fold plasticization stretching, water washing, 120°C drying, and 360°C high-temperature heat treatment to directly obtain the corresponding PMIA colored fibers.

[0183] Example 10

[0184] (1) Preparation of colored spinning solution: 1,4-diamino-2-methoxyanthracene-9,10-dione and meta-phenylenediamine are added to an appropriate amount of N-dimethylacetamide solvent at a molar ratio of 0.5:99.5, and isophthaloyl chloride is gradually added to the above solution in an equal amount within 2 hours according to the reaction stoichiometric ratio for gradual polymerization; meta-phenylenediamine and diaminoanthraquinone are directly polymerized in one step with isophthaloyl chloride in an equal amount or nearly equal amount to form PMIA colored spinning solution (solute mass concentration of 16.7%), and the feed amount is adjusted by temperature feedback to control the polymerization reaction temperature and time at -5°C for 1 hour in the first stage and at 20°C for 1 hour in the second stage.

[0185] (2) The prepared PMIA colored spinning solution was neutralized with calcium hydroxide, filtered, and degassed at a filtration pressure of 0.4 MPa. Then, the spinning pressure or the pressure in each spinning area was 0.6 MPa, the spinning temperature was 25°C, and the spinning feed rate was 6 m / min. Wet spinning and precipitation were performed to obtain primary fibers. The spinning process was smooth and there was basically no hair. The aperture of the spinning spinneret was 0.06 mm, and the precipitation solution was a mixture of N-dimethylacetamide, calcium chloride and water (the mass ratio of each component was 45:25:30).

[0186] (3) The spun fibers were subjected to 2-fold plasticization stretching, water washing, 120°C drying, and 360°C high-temperature heat treatment to directly obtain the corresponding PMIA colored fibers.

[0187] Embodiment 11

[0188] (1) Preparation of colored spinning solution: 1,5-diamino-4,8-dihydroxy-2-chloroanthraquinone and meta-phenylenediamine are added to an appropriate amount of N-dimethylacetamide solvent in a molar ratio of 0.5:99.5, and isophthaloyl chloride is gradually added to the above solution in an equal amount within 2 hours according to the reaction stoichiometric ratio for gradual polymerization; meta-phenylenediamine and diaminoanthraquinone react with isophthaloyl chloride in an equal amount or nearly equal amount in one step to directly polymerize into PMIA colored spinning solution (solute mass concentration of 16.7%), and the feed amount is adjusted by temperature feedback to control the polymerization reaction temperature and time at -5°C for 1 hour in the first stage and at 20°C for 1 hour in the second stage.

[0189] (2) The prepared PMIA colored spinning solution was neutralized with calcium hydroxide, filtered, and degassed at a filtration pressure of 0.4 MPa. Then, the spinning pressure or the pressure in each spinning area was 0.6 MPa, the spinning temperature was 25°C, and the spinning feed rate was 6 m / min. Wet spinning and precipitation were performed to obtain primary fibers. The spinning process was smooth and there was basically no hair. The aperture of the spinning spinneret was 0.06 mm, and the precipitation solution was a mixture of N-dimethylacetamide, calcium chloride and water (the mass ratio of each component was 45:25:30).

[0190] (3) The spun fibers were subjected to 2-fold plasticization stretching, water washing, 120°C drying, and 360°C high-temperature heat treatment to directly obtain the corresponding PMIA colored fibers.

[0191] Example 12

[0192] (1) Preparation of colored spinning solution: 4-[(4-nitrophenyl)azo]benzene-1,3-diamine and meta-phenylenediamine were added to an appropriate amount of N-dimethylacetamide solvent at a molar ratio of 0.5:99.5, and isophthaloyl chloride was gradually added to the above solution in an equal amount within 2 hours according to the reaction stoichiometric ratio for gradual polymerization; meta-phenylenediamine, azo aromatic diamine and isophthaloyl chloride in an equal amount or nearly equal amount were directly polymerized into PMIA colored spinning solution (solute mass concentration of 16.7%) by one-step reaction, and the feed amount was adjusted by temperature feedback to control the polymerization reaction temperature and time at -5°C for 1 hour in the first stage and at 20°C for 1 hour in the second stage.

[0193] (2) The prepared PMIA colored spinning solution was neutralized with calcium hydroxide, filtered, and degassed at a filtration pressure of 0.4 MPa. Then, the spinning pressure or the pressure in each spinning area was 0.6 MPa, the spinning temperature was 25°C, and the spinning feed rate was 6 m / min. Wet spinning and precipitation were performed to obtain primary fibers. The spinning process was smooth and there was basically no hair. The aperture of the spinning spinneret was 0.06 mm, and the precipitation solution was a mixture of N-dimethylacetamide, calcium chloride and water (the mass ratio of each component was 45:25:30).

[0194] (3) The spun fibers were subjected to 2-fold plasticization stretching, water washing, 120°C drying, and 360°C high-temperature heat treatment to directly obtain the corresponding PMIA colored fibers.

[0195] Comparative Example 1

[0196] Comparative Example 1 discloses a method for preparing PMIA colored fibers, which differs from Example 1 in that when preparing the colored spinning solution, no chromogenic monomer is added (i.e., the molar ratio of the chromogenic monomer to m-phenylenediamine is 0:100), and undyed PMIA fibers are further prepared.

[0197] Comparative Example 2 (Inorganic Dye Dyeing Method)

[0198] A method for preparing PMIA colored fiber, comprising the following steps:

[0199] (1) Grinding: Add the nano-scale inorganic pigment lead yellow into a ball mill for dispersion, and the maximum particle diameter after ball milling is less than 180 nm;

[0200] (2) preparing a dyeing solution: placing 4800 ml of dimethylacetamide in a ball mill circulation system, starting the circulation, adding 6 g of inorganic pigment into the circulation grinding three times, mixing the inorganic pigment and N-dimethylacetamide solvent at a mass ratio of 1:800, adding a dispersant, and placing the mixed solution on an ultrasonic oscillator to oscillate to obtain a uniform dyeing solution;

[0201] (3) preparing a spinning solution: dissolving 113.50 g of m-phenylenediamine in 10670 ml of N-dimethylacetamide solvent, cooling, adding 213.10 g of isophthaloyl chloride to carry out low-temperature solution polymerization, neutralizing with calcium hydroxide to obtain a poly(m-phenylene isophthalamide) spinning solution, and degassing, wherein the mass percentage concentration of salt is 8% and the mass percentage concentration of poly(m-phenylene isophthalamide) is 20%;

[0202] (4) Mixed solution: The dyeing solution and the spinning solution are added to the extruder head and mixed, and the mass ratio of the dyeing solution to the spinning solution is 1:650;

[0203] (5) The pre-spinning filtration pressure is 0.80 MPa, and the wet spinning process finds hairy fibers and broken finger lines, and then stretches, washes, dries, curls, cuts and packages to obtain PMIA colored fibers. The wet spinning process uses a coagulation bath to process the fibers, and the coagulation bath is an N-dimethylacetamide solution with a mass percentage concentration of 40% and a temperature of 30°C; the stretching temperature is 280°C, and the stretching multiple is 2.5 times.

[0204] Comparative Example 3 (Organic Dyeing Method)

[0205] PMIA dyeing was performed by referring to the method of Example 1 of CN202011083100.7. Compared with the scheme of CN202011083100.7, the dye of Comparative Example 2 was replaced with an equal amount of 1,4-diaminoanthraquinone, and the dyed fiber was the colorless PMIA fiber prepared in Comparative Example 1, which was composed of the following steps:

[0206] A. Degreasing: Add 8.5 g / L of sodium hydroxide to PMIA fiber, degrease for 20 min at 95°C, then wash and dry;

[0207] B. Pretreatment: The PMIA fiber treated in step A is placed in N-methylpyrrolidone solvent with a bath ratio of 1:15 and soaked at 60°C for 60 minutes; then, washed with water at 80°C for 30 minutes, dried in an oven at 80°C for standby use;

[0208] C. Dyeing: The PMIA fiber treated in step B is placed in a high-temperature dye solution for dyeing; the dye solution formula: 3% by mass of 1,4-diaminoanthraquinone, 30 g / L of N,N-diethyl-3-methylbenzamide, and 30 g / L of sodium chloride; dyeing conditions: pH value = 3 (adjusted by acetic acid), temperature 140°C, time 60 min, bath ratio 1:15;

[0209] D. Post-treatment: The PMIA fiber treated in step C is placed in a 2 g / L soap solution, cleaned for 30 min, washed with water for 30 min, dehydrated, and dried to obtain the dyed PMIA fiber.

[0210] Comparative Example 4

[0211] PMIA colored fibers were prepared by the method disclosed in Example 1, wherein the difference from Example 1 was that the molar ratio of m-phenylenediamine to the chromogenic reaction monomer was 75:25.

[0212] Comparative Example 5

[0213] PMIA colored fibers were prepared by the method disclosed in Example 1, which differed from Example 1 in that a PMIA colored spinning solution was generated and the temperature of the second stage of the polymerization reaction was controlled at 60°C.

[0214] Comparative Example 6

[0215] PMIA colored fibers were prepared by the method disclosed in Example 1, wherein the difference from Example 1 is that PMIA colored spinning solution was generated and the temperature of the first stage of the polymerization reaction was controlled at -30°C.

[0216] Comparative Example 7

[0217] PMIA colored fibers were prepared by the method disclosed in Example 1, wherein the difference from Example 1 is that PMIA colored spinning solution was generated and the temperature of the second stage of the polymerization reaction was controlled at 80°C.

[0218] Comparative Example 8

[0219] PMIA colored fibers were prepared by the method disclosed in Example 1, wherein the difference from Example 1 is that PMIA colored spinning solution was generated and the temperature of the first stage of the polymerization reaction was controlled at 20°C.

[0220] Comparative Example 9

[0221] PMIA colored fibers were prepared by the method disclosed in Example 1, which differed from Example 1 in that a PMIA colored spinning solution was generated and the temperature of the first stage of the polymerization reaction was controlled at -5°C.

[0222] Comparative Example 10

[0223] PMIA colored fibers were prepared by the method disclosed in Example 1, wherein the difference from Example 1 is that PMIA colored spinning solution was generated and the temperature of the entire polymerization reaction was controlled at 30°C.

[0224] Examples 1-12 and Comparative Examples 1-10 and undyed PMIA fibers were tested, wherein the light fastness grade was based on the standard of GB / T 8426-1998 Textiles - Tests for Color Fastness - Light Fastness - Daylight; the viscosity of the spinning solution was based on the relative viscosity [η]: the ratio of the dynamic viscosity of the spinning solution to the dynamic viscosity of the pure solvent at the same temperature. The results are shown in Table 1:

[0225] Table 1 Data related to spinning solution and fiber properties

[0226]

[0227]

[0228] Test conclusion:

[0229] As can be seen from Table 1, when the amount of the chromogenic reaction monomer in the reaction system accounts for 0.1% to 20% (the total molar ratio of metaphenylenediamine to the chromogenic reaction monomer is 80.0 to 99.9: 0.1 to 20.0), the viscosity [η] of the prepared spinning solution is 1.65 to 2.05, and the spinning solution has good spinnability. The fiber color can be adjusted based on the different chromogenic reaction monomers, and there is no fuzzy fibers or broken lines in the spinning process. The present invention significantly improves the fuzzy fibers and broken lines phenomenon compared with the existing inorganic dye dyeing method. The relative strength and elongation at break performance indicators of the colored fiber prepared by the method of the present invention in Example 1 are significantly improved compared with the conventional pigment coloring in Comparative Example 1 and Comparative Example 2.

[0230] As can be seen from Table 1, the glass transition temperature of the colored fibers prepared in Examples 1 to 12 is in the range of 260°C-278°C; the dynamic viscosity of the fibers is in the range of 13000 centipoise to 28000 centipoise; the relative strength of the fibers is in the range of 3.95 cN / dtex to 4.3 cN / dtex; the elongation at break of the fibers is in the range of 16.8% to 30%; the color fastness to light is grade 3 to 5; and the color fastness to washing is grade 4 to 5. Different chromogenic reaction monomers have different coloring effects, and different combinations of chromogenic reaction monomers can prepare new coloring effects different from any chromogenic reaction monomers.

[0231] The structures of 1,2-diaminoanthraquinone and 1,8-diaminoanthraquinone are similar to those of 1,4-diaminoanthraquinone, 1,5-diaminoanthraquinone and 2,6-diaminoanthraquinone. The experimental data of their use as chromogenic reaction monomers are similar to those of the latter three. Due to space limitations, they are not described one by one.

[0232] By comparing Examples 1, 5, 6 and Comparative Example 4, it can be seen that when the molar ratio of diaminoanthraquinone in the mixture with meta-phenylenediamine is higher than 20%, the glass transition temperature decreases significantly, the relative strength of the fiber decreases from 3.95 cN / dtex in Example 5 to 3.6 cN / dtex in Comparative Example 4, the glass transition temperature decreases by 5°C, the viscosity of the spinning solution decreases significantly, and the spinnability decreases significantly.

[0233] By comparing Example 1 and Comparative Example 2, it can be seen that the coloring scheme of the present invention has significantly improved the relative strength and light fastness grade of the fiber compared with ordinary inorganic dye dyeing, wherein the relative strength of the fiber is increased from 3.3 cN / dtex to 4.02 cN / dtex, the elongation at break of the fiber is increased from 15% to 16.8%, and the pre-spinning filtration pressure is reduced from 0.80 MPa to 0.4 MPa, which greatly reduces the filtration energy consumption.

[0234] By comparing Example 1 and Comparative Example 3, it can be seen that the coloring scheme of the present invention has significantly improved the relative strength and light fastness grade of the fiber compared with ordinary organic dye dyeing, wherein the relative strength of the fiber is increased from 3.5 cN / dtex to 4.02 cN / dtex, the light fastness grade is increased from 2-3 to 4, and the water washing color fastness grade is increased from 3 to 4.

[0235] Comparing Example 1 with Comparative Examples 5 and 7, it can be seen that the polymerization temperature in the second stage is higher than 60°C. Due to the increase of side reactions and the decrease of polymerization degree, the molecular weight of the colored fiber decreases, resulting in a decrease in spinnability, the phenomenon of broken finger lines, and the relative strength of the fiber and the elongation at break of the fiber are significantly reduced; at the same time, comparing Example 1 with Comparative Example 6, it can be seen that the polymerization temperature in the first stage is too low, which will also affect the final polymerization degree, and the relative strength of the fiber is reduced; the polymerization temperature is in the range of -20°C to 60°C, and the relative strength of the prepared colored fiber and the elongation at break of the fiber are in a good range. Comparing Example 1 with Comparative Example 10, it can be seen that the relative strength and elongation at break of the colored fiber prepared in Comparative Example 10, which did not undergo a low-temperature polymerization stage with a temperature less than or equal to 20°C, are significantly deteriorated.

[0236] By comparing Example 1 with Comparative Examples 1, 5, 7 and 9, it can be seen that when the polymerization reaction temperature is in the range of -5°C to 20°C, the molecular weight of the prepared colored fiber is closer to that of Comparative Example 1, and the relative strength of the fiber and the elongation at break of the fiber are in a better range.

[0237] The above description is only a preferred specific implementation manner of the present invention, but the protection scope of the present invention is not limited thereto. Any changes or substitutions that can be easily conceived by any technician familiar with the technical field within the technical scope disclosed by the present invention should be covered within the protection scope of the present invention.

Claims

1. A method for preparing polymer colored fibers, characterized in that: The following steps are involved: Step 1: Mixing a chromogenic reaction monomer and a first monomer and polymerizing them with a second monomer to prepare a poly(m-phenylene isophthalamide) colored spinning solution, wherein the chromogenic reaction monomer and the first monomer react with the second monomer to form an amide bond and are connected to the second monomer through the amide bond; the chromogenic reaction monomer is diaminoanthraquinone or azo aromatic diamine; the first monomer is m-phenylene diamine, and the second monomer is isophthaloyl chloride; Step 2: pre-treating the prepared poly(m-phenylene isophthalamide) colored spinning solution to remove impurities; Step 3: Spinning the pretreated poly(m-phenylene isophthalamide) colored spinning solution to obtain primary fibers; Step 4: post-treating the raw fiber to obtain poly(m-phenylene isophthalamide) colored yarn; In step 1, the molar ratio of the chromogenic monomer to the first monomer is in the range of 0.5:99.5 to 20:80; The preparation of the poly(m-phenylene isophthalamide) colored spinning solution in step 1 comprises the following steps: S101: dissolving a chromogenic monomer and a first monomer for preparing poly(m-phenylene isophthalamide) in a polar organic solvent; S102: gradually adding a second monomer for preparing poly(meta-phenylene isophthalamide) while stirring, and performing a polymerization reaction to obtain a poly(meta-phenylene isophthalamide) colored spinning solution; In step S102, the polymerization reaction for preparing the poly(m-phenylene isophthalamide) colored spinning solution includes a plurality of different reaction stages, and the polymerization reaction temperature of each reaction stage is different: The first stage: This stage mainly involves the reaction of the first monomer, the chromogenic monomer and the second monomer to generate a small molecule prepolymer and the random copolymerization of the small molecule prepolymer to generate a long chain prepolymer; The second stage: as the second monomer continues to be added, the second monomer reacts with the first monomer or the end group of the chromophoric reaction monomer of the prepolymer molecule to achieve long-chain prepolymer connection and long-chain growth; Gradual inclusion is achieved by: The total amount of the second monomer is divided into several equal or unequal portions, and a certain amount of the second monomer is added at a time interval, or a continuous feeding device is used; The addition time of the second monomer is 0.1h to 4h, and the polymerization reaction time is 0.1h to 4h.

2. The method for preparing polymer colored fibers according to claim 1, characterized in that: In the step 102, the polymerization reaction temperature is -20°C to 60°C.

3. The method for preparing polymer colored fibers according to claim 1, characterized in that: The diaminoanthraquinone is one or more of 1,4-diaminoanthraquinone, 1,5-diaminoanthraquinone, 2,6-diaminoanthraquinone, 1,5-diamino-4,8-dihydroxyanthraquinone, 1,2-diaminoanthraquinone, 1,8-diaminoanthraquinone, 1,4-diamino-2,3-diphenyloxyanthraquinone, 1,4-diamino-2,3-dichloroanthraquinone, 1,4-diamino-2-methoxyanthracene-9,10-dione and 1,5-diamino-4,8-dihydroxy-2-chloroanthraquinone, and / or the azo aromatic diamine is 4-[(4-nitrophenyl)azo]benzene-1,3-diamine.

4. The method for preparing polymer colored fibers according to claim 1, characterized in that: In step 101, the solvent is a polar organic solvent, and the polar organic solvent is any one of N-dimethylacetamide, dimethylformamide, and N-methylpyrrolidone.

5. A spinning solution for colored fibers, characterized in that: Prepared by step 1 of the method for preparing polymer colored fibers according to any one of claims 1 to 4, wherein the spinning solution comprises a colored polymer and a polar organic solvent; The colored polymer comprises: and The two structural units (Ⅰ) and (Ⅱ) are randomly distributed, and Aq contains an anthraquinone functional group or an aromatic azo group.

6. The spinning solution according to claim 5, characterized in that The viscosity of the spinning solution is 1.65 to 2.

05.

7. The spinning solution according to claim 6, characterized in that The quantitative ratio of the two structural units (I) and (II) in the colored polymer is 80-99.5:0.5-20.

8. A colored fiber, characterized in that: Prepared by the method for preparing polymer colored fibers according to any one of claims 1 to 4, the colored fibers contain randomly distributed two structural units (I) and (II): Aq contains anthraquinone functional group or aromatic azo group, and the quantity ratio of the two structural units (Ⅰ) and (Ⅱ) is 80-99.9:0.1-20; the dynamic viscosity is 13000 centipoise to 28000 centipoise.

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