Brominated acrylamide compound, azo reactive disperse dye and preparation and synchronous dyeing method

Abstract

The invention discloses a brominated acrylamide compound, an azo reactive disperse dye and a preparation and synchronous dyeing method. The preparation method comprises the following steps: by taking N-(3-aminoethyl)-N-ethyl-3-methylaniline as a monomer, carrying out nucleophilic substitution reaction on the N-(3-aminoethyl)-N-ethyl-3-methylaniline and 2, 3-dibromopropionyl chloride to obtain a coupling component with an active group; supercritical carbon dioxide fluid is used as a medium and an acid source, a coupling component with an active group and 3-amino-4-methoxy acetanilide are used as raw materials, diazotization and coupling reactions are completed in an SCF-CO2 reaction device through a one-bath method, and the azo reactive disperse dye is obtained. Meanwhile, the dye is dissolved in SCF-CO2, and synchronous dyeing of the sample is completed. The SCF-CO2 is taken as a main medium in a dye synthesis process and is taken as an acid source for diazotization and coupling reaction, the special azo reactive disperse dye is synthesized by a one-bath method, synchronous dyeing of the azo special dye on a sample can be simultaneously completed, the process flow from dye synthesis to dyeing is remarkably shortened, and the method is energy-saving, emission-reducing, green and ecological.

Description

Technical Field

[0001] This invention relates to the fields of dye synthesis and textile dyeing technology, and particularly to the preparation of a coupling component with an active group and an azo reactive disperse dye and its method for simultaneous dyeing with supercritical carbon dioxide (SCF-CO2) fluid. Background Technology

[0002] Compared with the recycling and reuse of wastewater in traditional dyeing processes, the SCF-CO2 dyeing process can solve the problem at its source, fundamentally eliminating the consumption of water resources by dyeing, making it more practical and cost-effective. This has profound and significant implications for the ecology, sustainable development, and technological innovation of my country's entire textile printing and dyeing industry (see: Investigations on the level dyeing of fabrics in supercritical carbon dioxide[J]. Journal of Supercritical Fluids, 2011, 57(1): 80-86.).

[0003] In recent years, research on azo dyes has mainly focused on reducing or eliminating color, salt, and heavy metals in industrial wastewater to mitigate environmental problems caused by dye synthesis, and on using greener, more eco-friendly aromatic amine intermediates and their reaction media systems and catalysts (see reference: Removal of azo dyes from synthetic wastewater using biochar derived from sewage sludge to prevent groundwater contamination[J]. Urban Climate, 2023, 49: 101502.). However, although SCF-CO2 has been used as an alternative to water-based media in fiber dyeing research and considerable progress has been made, research on using SCF-CO2 as a reaction media in the synthesis of azo dyes remains extremely limited. In addition, most newly developed reactive disperse dyes currently involve first synthesizing the dye, and then conducting SCF-CO2 dyeing experiments and related performance tests, which is a rather complicated process (see the literature: Ecofriendly synthesis and application of special disperse reactive dyes inwaterless coloration of wool with supercritical carbon dioxide[J]. Journal of Cleaner Production, 2016, 133: 746-756.). Summary of the Invention

[0004] This invention addresses the shortcomings of existing SCF-CO2-specific dye synthesis and the problem that dye synthesis cannot be carried out simultaneously with SCF-CO2 dyeing. It provides a method for preparing azo reactive disperse dyes with active groups, which have high directness to natural fibers and stable physicochemical properties, and for using them for simultaneous SCF-CO2 dyeing.

[0005] The technical solution to achieve the objective of this invention is to provide a brominated acrylamide compound with the following general structural formula: , Where R1 is CH3 or C2H5; R2 is H or CH3; 0≤n≤6.

[0006] The preferred embodiment is a brominated acrylamide compound, wherein R1 is C2H5; R2 is CH3; and n=1.

[0007] The preparation method of the above-mentioned brominated acrylamide compound is as follows: aniline compound is dissolved in an organic solvent at a concentration of 0.05–0.15 mol / L, and a polymerization inhibitor at a concentration of 100–1000 ppm is added; halopropionyl chloride is dissolved in an organic solvent at a molar ratio of aniline compound to halopropionyl chloride of 1:1–1:2, and slowly added to the aniline compound solution. Under a nitrogen and / or argon protective atmosphere and at a temperature of -3–3℃, the reaction is carried out for 15–30 min. After the system temperature rises to 20–30℃, an alkali agent is added and the reaction is carried out for 1–2 h. After purification, a brominated acrylamide compound is obtained.

[0008] The preferred embodiment is that the aniline compound is N-(3-aminoethyl)-N-ethyl-3-methylaniline; the halopropionyl chloride is 2,3-dibromopropionyl chloride; the polymerization inhibitor is polymerization inhibitor 701; the organic solvent is one or more of N,N-dimethylformamide, acetone, and dichloromethane; the alkaline agent is one or more of potassium hydroxide, sodium hydroxide, triethylamine, sodium carbonate, and potassium carbonate; the purification process is carried out using silica gel column purification, the silica gel powder is 200-300 mesh, and the eluent includes petroleum ether and dichloromethane.

[0009] The technical solution of the present invention also includes providing an azo reactive disperse dye for SCF-CO2 staining, the general structural formula of which is: , Wherein, R1 is CH3 or C2H5; R2 is H or CH3; R3 is CH3 or OCH3; R4 is CH3 or NHCOCH3; 0≤n≤6.

[0010] The preferred embodiment is a structural formula in which: R1 is C2H5; R2 is CH3; R3 is OCH3; R4 is NHCOCH3; n=1.

[0011] The preparation method of the above-mentioned azo reactive disperse dye is as follows: Acetanilide compound is added to an SCF-CO2 reaction apparatus at a concentration of 0.0001–0.001 mol / L. The aforementioned bromoacrylamide compound is added to the SCF-CO2 reaction apparatus at a molar ratio of acetanilide to bromoacrylamide of 1:1–1:2. A salt solution with a concentration of 0.05–0.15 mol / L is then added, with a molar ratio of acetanilide to salt of 1:1–1:3. The reaction is carried out at a temperature of 40–90℃ and a pressure of 8–13 MPa for 1–6 h. The diazotization and coupling reaction are completed in a one-bath process in SCF-CO2. After purification, an azo reactive disperse dye is obtained.

[0012] The preferred embodiment is that the bromoacrylamide compound is [2-bromo-N-(2-(ethyl(m-tolyl)amino)ethyl)acrylamide]; the acetanilide compound is 3-amino-4-methoxyacetanilide; the salt solution is an aqueous solution of sodium nitrite; the purification process is carried out using a silica gel column with silica gel powder of 200-300 mesh, and the eluent includes ethyl acetate and acetone.

[0013] The technical solution of this invention also includes a method for simultaneously staining a sample while synthesizing an azo reactive disperse dye: the sample is fixed in an SCF-CO2 reaction apparatus, an acetanilide compound is added to the SCF-CO2 reaction apparatus at a concentration of 0.0001–0.001 mol / L, a bromoacrylamide compound is added to the SCF-CO2 reaction apparatus at a molar ratio of acetanilide to bromoacrylamide of 1:1–1:2, and a salt solution at a concentration of 0.05–0.15 mol / L is added at a molar ratio of acetanilide to salt solution of 1:1–1:3; the reaction is carried out for 1–6 h at a temperature of 40–90 °C and a pressure of 8–13 MPa, and the diazotization and coupling reaction are completed in a one-bath process in the SCF-CO2 reaction apparatus. After the obtained azo reactive disperse dye diffuses, the sample is simultaneously stained.

[0014] Based on the properties of SCF-CO2, this invention uses SCF-CO2 as the main reaction medium and acid source to carry out diazotization and coupling reactions, synthesizes azo dyes in a one-bath process, and simultaneously dyes fibers or their products.

[0015] Compared with the prior art, the beneficial effects of the present invention are as follows: 1. This invention uses N-(3-aminoethyl)-N-ethyl-3-methylaniline as a monomer and inserts an α-bromoacrylamide-type active group into its structure to complete the modification of the coupling component of traditional azo dyes, providing a new dye modification approach.

[0016] 2. The azo reactive disperse dyes provided by this invention have good directness to natural fibers, high reaction yield, and dyes with different colors and properties can be obtained by changing different diazo components and modified coupling components.

[0017] 3. This invention provides a method for synthesizing azo reactive disperse dyes in a one-bath process using SCF-CO2 as the main medium in the dye synthesis process and replacing the traditional acid source for diazotization and coupling reactions, thereby reducing the use of organic solvents, acids, alkalis and salt solutions in the dye synthesis process.

[0018] 4. This invention achieves simultaneous dyeing of fibers or their products by using SCF-CO2 as the dyeing medium while simultaneously synthesizing azo reactive disperse dyes in a one-bath process, thus shortening the dyeing process and reducing water consumption. Attached Figure Description

[0019] Figure 1 This is a schematic diagram illustrating the synthetic route principle of the bromoacrylamide compound and azo reactive disperse dye provided in Examples 1 and 2 of the present invention.

[0020] Figure 2 The Fourier transform infrared spectrum of the brominated acrylamide compound provided in Example 1 of this invention.

[0021] Figure 3 The Fourier transform infrared spectrum of the azo reactive disperse dye provided in Example 2 of this invention.

[0022] Figure 4 The infrared spectra of cotton fabrics before and after simultaneous dyeing with azo reactive disperse dyes provided in Example 3 of the present invention are shown. Detailed Implementation

[0023] The technical solution of the present invention will be further described below with reference to the accompanying drawings and embodiments. Example 1

[0024] See appendix Figure 1 This is a schematic diagram illustrating the synthetic route principle of the bromoacrylamide compound and azo reactive disperse dye provided in Examples 1 and 2 of the present invention.

[0025] In this embodiment, N-(3-aminoethyl)-N-ethyl-3-methylaniline and 2,3-dibromopropionyl chloride were used as reactants to prepare a brominated acrylamide compound. The specific steps are as follows: Weigh 1 mmol (0.178 g) of N-(3-aminoethyl)-N-ethyl-3-methylaniline and place it in a three-necked flask. Add 10 mL of dichloromethane to dissolve it. Add 500 ppm of polymerization inhibitor 701 to the system. Cool the mixture to 1°C using a low-temperature constant-temperature stirring reaction bath and start stirring.

[0026] 1.5 mmol (0.375 g) of 2,3-dibromopropionyl chloride was dissolved in 10 mL of dichloromethane and slowly added dropwise to the three-necked flask over 15 min using a constant-pressure funnel. The inner wall of the funnel was rinsed three times with 5 mL of dichloromethane, at which point the reaction was complete. The reaction temperature was raised to 25 °C, and 1.5 mL of triethylamine was added to the reaction system. The reaction was allowed to proceed for 1.5 h. The entire reaction was carried out under nitrogen protection.

[0027] After the reaction, the product was separated and purified using a silica gel column with petroleum ether and dichloromethane as eluents. The separated fraction was then subjected to low-pressure rotary evaporation and vacuum drying to obtain a bromoacrylamide compound with a yield of 95%. The structural formula of the prepared bromoacrylamide compound is as follows: , The brominated acrylamide compounds obtained in this example were characterized by Fourier transform infrared spectroscopy, and the results are shown in the appendix. Figure 2 The infrared spectrum shows that at a wavenumber of 3275 cm⁻¹ -1 The peak at this location is the stretching vibration peak of -NH-; at a wavenumber of 3079 cm⁻¹ -1 The vibration peak at point C is the stretching peak of C=C; at wavenumber 2972 ​​cm⁻¹ -1 2930cm -1 2892 cm -1 2867 cm -1 The multiplet at 1652 cm⁻¹ represents the antisymmetric and symmetric vibrational peaks of CH in -CH₃ and -CH₂; -1 The sharp characteristic peak at this point is the stretching vibration peak of C=O; the wavenumber is 1599 cm⁻¹. -1 The characteristic peak at 578 cm⁻¹ represents the skeletal vibration of substituted benzene in the structure of the coupled component with the active group; -1 The peak at this location represents the stretching vibration of C-Br.

[0028] The bromoacrylamide compound provided in this embodiment, as a modified coupling component, has active reactive groups and can be used as a raw material for synthesizing other dyes or compounds with other diazo components. In this invention, it is used as a coupling component for the synthesis of azo reactive disperse dyes. Example 2

[0029] This embodiment uses SCF-CO2 as the main medium and acid source, and the bromoacrylamide compound and 3-amino-4-methoxyacetanilide provided in Example 1 as raw materials. Diazotization and coupling reactions are completed in a one-bath process in an SCF-CO2 reactor to obtain reactive disperse dyes, while simultaneously dyeing samples (cotton fabrics). The principle of the synthetic route is detailed in the appendix. Figure 1 The specific steps are as follows: Weigh 0.0625 mmol (0.018 g) of bromoacrylamide compound, 0.05 mmol (0.009 g) of 3-amino-4-methoxyacetanilide, and 0.125 mmol (0.009 g) of sodium nitrite, and place them in an SCF-CO2 reaction apparatus. Then add 1.5 mL of water to the system and mix the above substances thoroughly. Fix a 1 g sample of cotton fabric on the rotating shaft of the stirring apparatus.

[0030] The SCF-CO2 reactor was heated to 60°C using a heating device, and the pressure was increased to 10 MPa. This was the start time for the reaction. The equipment was then put into heat preservation and pressure maintenance mode, and the stirring device was started at a speed of 150 r / min. The reaction was completed after 5 hours. After the reaction, the SCF-CO2 reactor was opened, and the dyed cotton fabric sample was removed.

[0031] The entire apparatus was cleaned with ethanol to collect the remaining dye. The product was then separated and purified using silica gel column chromatography with ethyl acetate and acetone as eluents. The separated components were then subjected to low-pressure rotary evaporation and vacuum drying to obtain an azo reactive disperse dye with a yield of 76%. The structural formula of the prepared azo reactive disperse dye is as follows: , The azo reactive disperse dyes obtained in Example 2 were characterized using Fourier transform infrared spectroscopy, and the results are shown in the appendix. Figure 3 The infrared spectrum shows 3284 cm⁻¹ -1 The peak at this location is the stretching vibration peak of -NH-; at a wavenumber of 2926 cm⁻¹ -1 2851cm -1 The multiplet at this point represents the antisymmetric and symmetric vibrational peaks of CH in -CH3 and -CH2; the wavenumber is 1654 cm⁻¹. -1 The peak value is the stretching vibration peak at C=O; the wavenumber is 1596 cm⁻¹. -1 The characteristic peak at 1229 cm⁻¹ represents the skeletal vibration of substituted benzene in the dye structure. -1 and 1017cm -1 The peaks at 580 cm⁻¹ represent the antisymmetric and symmetric stretching peaks of COC, respectively; the characteristic peak of C-Br is at a wavenumber of 580 cm⁻¹. -1 Place. Example 3

[0032] In this embodiment, the original cotton fabric sample after washing and drying, and the cotton fabric sample after simultaneous dyeing provided in Example 2, were cut into powder. Fourier transform infrared spectroscopy was used to test the cotton fabrics before and after simultaneous dyeing. The testing method was as follows: using the KBr pellet method at 4000–400 cm⁻¹. -1 The sample was tested within the specified wavenumber range, with 64 scans and a resolution of 4 cm⁻¹. -1 The results are shown in the appendix. Figure 4 Figure A shows the infrared absorption spectrum of the original cotton fabric, and Figure B shows the infrared absorption spectrum of the cotton fabric after simultaneous dyeing with azo reactive disperse dyes.

[0033] like Figure 4 As shown, at a wavenumber of 3284 cm⁻¹ -1The peak at 1543 cm⁻¹ represents the stretching vibration of the -NH⁻ group in the structure of azo reactive disperse dyes. -1 The peak at this location represents the in-plane bending vibration of NH in the structure of azo reactive disperse dyes; the wavenumber is 1501 cm⁻¹. -1 The characteristic peak at 809 cm⁻¹ is the stretching vibration peak of CN in the structure of azo reactive disperse dyes; -1 The peak at this point represents the out-of-plane bending vibration of the NH group in the structure of azo reactive disperse dyes. The above analytical results indicate that azo reactive disperse dyes successfully dyed cotton fibers.

Claims

1. A brominated acrylamide compound, characterized in that... Its general structural formula is: ， Where R1 is CH3 or C2H5; R2 is H or CH3; 0≤n≤6.

2. The brominated acrylamide compound according to claim 1, characterized in that: R1 is C2H5; R2 is CH3; n=1.

3. The method for preparing the brominated acrylamide compound according to claim 1, characterized in that: Aniline compound is dissolved in an organic solvent at a concentration of 0.05–0.15 mol / L, and a polymerization inhibitor at a concentration of 100–1000 ppm is added. Halopropionyl chloride is dissolved in the organic solvent at a molar ratio of aniline compound to halopropionyl chloride of 1:1–1:2, and slowly added to the aniline compound solution. Under a nitrogen and / or argon protective atmosphere and at a temperature of -3–3°C, the reaction is carried out for 15–30 min. After the system temperature rises to 20–30°C, an alkali is added and the reaction is carried out for 1–2 h. After purification, a brominated acrylamide compound is obtained.

4. The method for preparing the brominated acrylamide compound according to claim 3, characterized in that: The aniline compound is N-(3-aminoethyl)-N-ethyl-3-methylaniline; the halopropionyl chloride is 2,3-dibromopropionyl chloride; the polymerization inhibitor is polymerization inhibitor 701; the organic solvent is one or more of N,N-dimethylformamide, acetone, and dichloromethane; the alkaline agent is one or more of potassium hydroxide, sodium hydroxide, triethylamine, sodium carbonate, and potassium carbonate; the purification process uses silica gel column purification, the silica gel powder is 200-300 mesh, and the eluent is selected from petroleum ether and dichloromethane.

5. An azo reactive disperse dye, characterized in that... Its general structural formula is: ， Wherein, R1 is CH3 or C2H5; R2 is H or CH3; R3 is CH3 or OCH3; R4 is CH3 or NHCOCH3; 0≤n≤6.

6. The azo reactive disperse dye according to claim 5, characterized in that: R1 is C2H5; R2 is CH3; R3 is OCH3; R4 is NHCOCH3; n=1.

7. The method for preparing the azo reactive disperse dye according to claim 5, characterized in that: Acetaniline compound is added to an SCF-CO2 reaction apparatus at a concentration of 0.0001–0.001 mol / L. Bromoacrylamide compound as described in claim 3 is added to the SCF-CO2 reaction apparatus at a molar ratio of acetaniline compound to bromoacrylamide compound of 1:1–1:

2. A salt solution with a concentration of 0.05–0.15 mol / L is then added, with a molar ratio of acetaniline compound to salt of 1:1–1:

3. The reaction is carried out for 1–6 h at a temperature of 40–90 °C and a pressure of 8–13 MPa. The diazotization and coupling reaction are completed in a one-bath process in SCF-CO2. After purification, an azo reactive disperse dye is obtained.

8. The method for preparing azo reactive disperse dyes according to claim 7, characterized in that: The bromoacrylamide compound is [2-bromo-N-(2-(ethyl(m-tolyl)amino)ethyl)acrylamide]; the acetanilide compound is 3-amino-4-methoxyacetanilide; the salt solution is an aqueous solution of sodium nitrite; the purification process is carried out using a silica gel column, the silica gel powder is 200-300 mesh, and the eluent is selected from ethyl acetate and acetone.

9. The simultaneous dyeing method using the azo reactive disperse dye as described in claim 5, characterized in that: The sample was fixed in an SCF-CO2 reaction apparatus. Acetaniline compound was added to the SCF-CO2 reaction apparatus at a concentration of 0.0001–0.001 mol / L. The bromoacrylamide compound described in claim 3 was added to the SCF-CO2 reaction apparatus at a molar ratio of acetaniline compound to bromoacrylamide compound of 1:1–1:

2. A salt solution with a concentration of 0.05–0.15 mol / L was then added, with a molar ratio of acetaniline compound to salt solution of 1:1–1:

3. The reaction was carried out for 1–6 h at a temperature of 40–90 °C and a pressure of 8–13 MPa. The diazotization and coupling reaction were completed in a one-bath process in the SCF-CO2 reaction apparatus. After the azo reactive disperse dye was diffused, the sample was simultaneously stained.

10. The simultaneous staining method according to claim 9, characterized in that: The bromoacrylamide compound is [2-bromo-N-(2-(ethyl(m-tolyl)amino)ethyl)acrylamide]; the acetanilide compound is 3-amino-4-methoxyacetanilide; and the salt solution is an aqueous solution of sodium nitrite.

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