Dyeing accelerant as well as preparation method and application thereof

Abstract

The invention provides a dyeing accelerant as well as a preparation method and application thereof. The molecular formula of the dyeing accelerant is shown as a formula I: # imgabs0 #, the molecular weight of the dyeing accelerant is 4 * 10 < 5 >-6 * 10 < 5 >, and the ratio of n to m is 1: 1. The dyeing accelerant provided by the invention is a double-active-group polymer simultaneously containing a quaternary ammonium salt cation group and an epoxy group, the quaternary ammonium salt cation group reacts with reactive dye anions, and meanwhile, the epoxy group reacts with cellulose fibers, so that a'bridge 'effect is achieved between dye molecules and cellulose fiber molecules; therefore, dye utilization rate is improved and inorganic salt consumption is reduced. Therefore, the clean production level of the printing and dyeing industry is improved, and good economic and social benefits are achieved.

Description

Technical Field

[0001] The invention relates to the technical field of dye auxiliaries, in particular to a dyeing accelerator and a preparation method and application thereof. Background Art

[0002] Reactive dyes have the characteristics of complete color spectrum, bright color, good level dyeing and high color fastness. They are currently the main dyes used for dyeing and printing cellulose fibers, with an annual usage of nearly 260,000 tons, accounting for about 27.9% of all dyes.

[0003] At present, the main problems of reactive dye dyeing are low fixation rate and low dye utilization rate. This is because reactive dyes are in anionic state in the dye bath, and cellulose fibers also carry negative charges in the dye bath, resulting in low directness and affinity of reactive dyes. During the dyeing process, as the dye is adsorbed by the fiber, the dye anions adsorbed on the fiber surface make the fiber present more negative charges, which will hinder the dye from continuing to approach the fiber surface, resulting in low reactive dye uptake. Therefore, a large amount of inorganic salts need to be added to promote dyeing during the reactive dye dyeing process. After adding inorganic salts, Na + The charge shielding effect reduces the repulsion between the dye and the fiber, thereby increasing the equilibrium adsorption of the dye. Generally, the amount of dyeing salt used for exhaust dyeing is 30-70g / L, and the amount of dyeing salt used for continuous pad dyeing is 200-250g / L. Due to the consumption of a large amount of inorganic salts, the dyeing cost increases, and the inorganic salt concentration in the wastewater is seriously excessive.

[0004] In addition, since the nucleophilicity of the hydroxyl groups on cellulose fibers will be significantly enhanced under alkaline conditions, the fixation reaction of most reactive dyes is carried out under alkaline conditions. However, under alkaline conditions, the hydrolysis reaction of reactive dyes will also be enhanced. In most cases, the hydrolyzed dyes can reach 20% to 40%, and in severe cases it can reach more than 50%, which is also the main reason for the low utilization rate of reactive dyes. In order to remove the hydrolyzed and unfixed dyes, a time-consuming and energy-consuming washing process is required after dyeing, which not only produces a large amount of wastewater, but also has high alkalinity, high salinity, high chroma, and complex pollutant composition, making subsequent wastewater treatment more difficult.

[0005] In view of the problems of low dye utilization and high inorganic salt consumption in the above-mentioned reactive dye dyeing process, it is imperative to develop dyeing accelerators that can improve dye utilization, reduce inorganic salt consumption, and achieve color fixation and synergistic effects. Summary of the invention

[0006] 1. Technical issues to be solved

[0007] In view of the deficiencies in the prior art, the present invention provides a dyeing accelerator and a preparation method and application thereof, introduces cationic groups that can promote dyeing and reactive groups that can act as a "bridge" between dye molecules and fiber molecules, and solves the problems raised in the above-mentioned background technology.

[0008] (II) Technical solution

[0009] To achieve the above objectives, the present invention is implemented through the following technical solutions:

[0010] According to a first aspect of the present invention, a dyeing accelerator is provided, wherein the molecular formula of the dyeing accelerator is as shown in Formula I:

[0011]

[0012] Wherein, the molecular weight of the dyeing accelerator is 4×10 5 ~6×10 5 , the ratio of n to m is 1:1.

[0013] The dyeing accelerator provided by the present invention is a polymer having a quaternary ammonium salt cationic group and an epoxy group. The quaternary ammonium salt cationic group of the dyeing accelerator reacts with an anion of a reactive dye, and the epoxy group reacts with cellulose fibers. The dyeing principle is shown in Formula II.

[0014]

[0015] Therefore, during the dyeing process, it acts as a "bridge" between the dye molecules and the cellulose fiber molecules, allowing the unfixed dyes and hydrolyzed dyes to continue to react with the cellulose fibers, thereby improving the dye fixation rate, color fastness and utilization rate, and reducing the consumption of inorganic salts.

[0016] According to a second aspect of the present invention, a method for preparing a dyeing accelerator is provided, wherein dimethyldiallylammonium bromide and allyl glycidyl ether are used as reaction monomers, an initiator is added, and a free radical polymerization reaction is carried out to obtain the dyeing accelerator.

[0017] The reaction equation is shown in Formula III:

[0018]

[0019] A specific preparation method of a dyeing accelerator of the present invention comprises the following steps:

[0020] a. Fully dissolving the dimethyldiallylammonium bromide in distilled water to obtain a first solution;

[0021] Fully dissolving the allyl glycidyl ether in ethanol to obtain a second solution;

[0022] b. Add the first solution into a four-necked flask, and introduce nitrogen to maintain the four-necked flask in a nitrogen positive pressure state;

[0023] c. Add the second solution and the initiator dropwise into the first solution to obtain a reaction solution, perform a free radical polymerization reaction, and cool the temperature to room temperature to obtain the dyeing accelerator.

[0024] The four-necked flask of the present invention is equipped with a thermometer, a stirrer and a gas guide tube.

[0025] Preferably, in step c, the total monomer concentration of dimethyldiallylammonium bromide and allyl glycidyl ether in the reaction solution is 20-40%.

[0026] Preferably, in step c, the amount of the initiator added is 0.4-1.1% of the reaction solution.

[0027] Preferably, in step c, the mass ratio of dimethyldiallylammonium bromide to allyl glycidyl ether in the reaction solution is 2 to 5:1.

[0028] Preferably, in step c, the temperature of the free radical polymerization reaction is 60 to 90° C., and the time of the free radical polymerization reaction is 4 to 8 hours.

[0029] Preferably, in step c, the initiator is selected from sodium persulfate or ammonium persulfate.

[0030] Preferably, in step c, the second solution and the initiator are added dropwise for 1.5 to 2.5 hours.

[0031] According to a third aspect of the present invention, there is provided a use of a dyeing accelerator in dyeing with reactive dyes.

[0032] (III) Beneficial effects

[0033] The present invention provides a dyeing accelerator and a preparation method and application thereof, which have the following beneficial effects:

[0034] (1) The dyeing accelerator provided in this scheme is a dual-active polymer having both a quaternary ammonium salt cationic group and an epoxy group. The quaternary ammonium salt cationic group reacts with the anion of the active dye, and the epoxy group reacts with the cellulose fiber, playing a "bridge" role between the dye molecule and the cellulose fiber molecule, thereby improving the dye fixation rate, color fastness and utilization rate, and reducing the consumption of inorganic salts. This will further improve the clean production level of the printing and dyeing industry, with good economic and social benefits.

[0035] (2) The present invention provides a dyeing accelerator, wherein the quaternary ammonium salt cation in the dyeing accelerator can also form ion bonds with the hydrolyzed dye and the unfixed dye, thereby further improving the utilization rate of the dye and reducing the consumption of inorganic salts during the dyeing process.

[0036] (3) The present invention provides a method for preparing a dyeing accelerator. The preparation method is simple and can achieve the polymerization reaction of dimethyldiallylammonium bromide and allyl glycidyl ether by adding an initiator. BRIEF DESCRIPTION OF THE DRAWINGS

[0037] Figure 1 The present invention is a dyeing process curve diagram of the dyeing accelerator prepared in the present invention during the dyeing process. DETAILED DESCRIPTION

[0038] In order to better illustrate the content of the present invention, a detailed description is given below in conjunction with specific embodiments.

[0039] The specific dyeing process of the dyeing accelerator of the present invention in reactive dye dyeing is as follows:

[0040] Dye, anhydrous sodium sulfate, sodium carbonate and dyeing accelerator were mixed as follows: Figure 1 The dyeing process curve shown is used to dye cotton fabrics, and the color fixation rate and color fastness of the dyed products are tested;

[0041] Among them, the dosage of dye is 2% (owf), the dosage of anhydrous sodium sulfate is 20g / L, the dosage of sodium carbonate is 20g / L, and the dosage of dyeing accelerator is 3g / L.

[0042] Determination of the dyeing accelerator conversion rate in the present invention:

[0043] Weigh a certain amount of dyeing accelerator, dry it at 105°C to constant weight, and calculate the actual solid content Y and monomer conversion rate according to formula (1) and formula (2):

[0044]

[0045] In formula (1), W 0 is the mass of dyeing accelerator before drying; W 1 The quality of dyeing accelerator after drying;

[0046]

[0047] Example 1

[0048] A method for preparing a dyeing accelerator comprises the following steps:

[0049] 0.45 kg of dimethyldiallylammonium bromide (DMDAABr) and 2 L of distilled water are placed in a four-necked flask equipped with a thermometer, a stirrer and an air guide tube, and stirred to obtain a first solution. Nitrogen is introduced to remove oxygen in the four-necked flask. After nitrogen is continuously introduced for 10 minutes, the nitrogen in the four-necked flask is in a positive pressure state; 0.15 kg of allyl glycidyl ether (AGE) is dissolved in 100 mL of ethanol to obtain a second solution; the second solution and a sodium persulfate aqueous solution are dropped into the four-necked flask containing the first solution to obtain a reaction solution, the initial solubility of the total amount of monomers in the reaction solution is controlled to be 30%, the amount of initiator used is 0.5% of the reaction solution, the mass ratio of AGE to DMDAABr is 1:3, and a free radical polymerization reaction is carried out at 80° C. for 6 hours to obtain a dyeing accelerator.

[0050] Reactive Orange 2RH dye was used to dye cotton fabric, wherein the amount of Reactive Orange 2RH dye was 2% (owf), the amount of anhydrous sodium sulfate was 20 g / L, the amount of sodium carbonate was 20 g / L, and the amount of dyeing accelerator was 3 g / L.

[0051] Example 2

[0052] The preparation method of this embodiment is the same as that of embodiment 1, except that the mass ratio of AGE to DMDAABr in the reaction solution is 1:2.

[0053] Example 3

[0054] The preparation method of this embodiment is the same as that of embodiment 1, except that the mass ratio of AGE to DMDAABr in the reaction solution is 1:4.

[0055] Example 4

[0056] The preparation method of this embodiment is the same as that of embodiment 1, except that the mass ratio of AGE to DMDAABr in the reaction solution is 1:5.

[0057] Example 5

[0058] The preparation method of this embodiment is the same as that of embodiment 1, except that the total initial concentration of AGE and DMDAABr monomers in the reaction solution is 20%.

[0059] Example 6

[0060] The preparation method of this embodiment is the same as that of embodiment 1, except that the total initial solubility of AGE and DMDAABr monomers in the reaction solution is 40%.

[0061] Example 7

[0062] The preparation method of this embodiment is the same as that of embodiment 1, except that the amount of the initiator used is 0.4%.

[0063] Example 8

[0064] The preparation method of this embodiment is the same as that of embodiment 1, except that the amount of the initiator used is 0.7%.

[0065] Example 9

[0066] The preparation method of this embodiment is the same as that of embodiment 1, except that the amount of the initiator used is 0.9%.

[0067] Example 10

[0068] The preparation method of this embodiment is the same as that of embodiment 1, except that the amount of the initiator used is 1.1%.

[0069] Embodiment 11

[0070] The preparation method of this embodiment is the same as that of embodiment 1, except that the temperature of the free radical polymerization reaction is 60°C.

[0071] Example 12

[0072] The preparation method of this embodiment is the same as that of embodiment 1, except that the temperature of the free radical polymerization reaction is 70°C.

[0073] Embodiment 13

[0074] The preparation method of this embodiment is the same as that of embodiment 1, except that the temperature of the free radical polymerization reaction is 90°C.

[0075] Embodiment 14

[0076] The preparation method of this embodiment is the same as that of embodiment 1, except that the free radical polymerization reaction time is 4 hours.

[0077] Embodiment 15

[0078] The preparation method of this embodiment is the same as that of embodiment 1, except that the free radical polymerization reaction time is 5 hours.

[0079] Example 16

[0080] The preparation method of this embodiment is the same as that of embodiment 1, except that the free radical polymerization reaction time is 7 hours.

[0081] Embodiment 17

[0082] The preparation method of this embodiment is the same as that of embodiment 1, except that the free radical polymerization reaction time is 9 hours.

[0083] Comparative Example 1

[0084] The preparation method of this comparative example is the same as that of Example 1, except that the mass ratio of AGE to DMDAABr in the reaction solution is 1:1.

[0085] Comparative Example 2

[0086] The preparation method of this comparative example is the same as that of Example 1, except that the mass ratio of AGE to DMDAABr in the reaction solution is 1:6.

[0087] Comparative Example 3

[0088] The preparation method of this comparative example is the same as that of Example 1, except that the total initial solubility of AGE and DMDAABr monomers in the reaction solution is 10%.

[0089] Comparative Example 4

[0090] The preparation method of this comparative example is the same as that of Example 1, except that the total initial solubility of AGE and DMDAABr monomers in the reaction solution is 50%.

[0091] Comparative Example 5

[0092] The preparation method of this comparative example is the same as that of Example 1, except that the amount of the initiator used is 0.3%.

[0093] Comparative Example 6

[0094] The preparation method of this comparative example is the same as that of Example 1, except that the amount of the initiator used is 1.2%.

[0095] Comparative Example 7

[0096] The preparation method of this comparative example is the same as that of Example 1, except that the temperature of the free radical polymerization reaction is 50°C.

[0097] Comparative Example 8

[0098] The preparation method of this comparative example is the same as that of Example 1, except that the temperature of the free radical polymerization reaction is 100°C.

[0099] The conversion rates of the dyeing accelerators of Examples 1 to 17 of the present invention and Comparative Examples 1 to 8, as well as the color fixation rates and color fastnesses of the reactive orange 2RH dye were measured respectively. The measurement results are shown in Table 1.

[0100] Table 1

[0101]

[0102]

[0103] According to the data of Examples 1 to 4 and Comparative Examples 1 and 2 in Table 1, as the mass ratio of monomer AGE to DMDAABr becomes higher and higher, the reaction conversion rate gradually increases, the cationic group of the dyeing accelerator can attract the fuel anion, and the appropriate increase in the proportion of cationic monomers can improve the color fixation effect. However, as the proportion of DMDAABr increases, its steric hindrance will also increase, and the activity of the dyeing accelerator will decrease. At the same time, the proportion of epoxy groups in the dyeing accelerator decreases, and the film-forming property of the dyeing accelerator on the fiber surface will deteriorate, which affects the color fixation rate and color fastness of the dyed product to a certain extent.

[0104] According to the data of Example 1, Examples 5 to 6 and Comparative Examples 3 to 4, when the initial total monomer concentration in the reaction solution is low, the chances of collision between the monomer and the initiator free radicals are small, and the polymerization reaction conversion rate is low. As the initial total monomer concentration in the reaction solution increases, the chances of collision between chain growth free radicals increase, and the free radical polymerization rate accelerates. However, when the concentration of the reactants is too high, the temperature of the polymerization reaction system rises rapidly, and the probability of chain termination increases, resulting in a decrease in the molecular weight of the polymer, and further resulting in a decrease in the color fixation rate and color fastness of the dyed product.

[0105] According to the data of Example 1, Example 7 to Example 10 and Comparative Examples 5 to 6, when the amount of initiator is too low, the initiator efficiency is low, and the polymerization reaction is slow. As the amount of initiator increases, decomposition and cage effect loss can be induced, which is sufficient to initiate the reaction and improve the monomer conversion rate. However, when the amount of initiator is too much, the number of free radicals in the reaction system is too large, the free radicals are easy to interact with each other, the reaction speed is too fast, resulting in a rapid increase in the temperature of the reaction system, and a violent polymerization phenomenon is prone to occur, thereby reducing the color fixation rate and color fastness of the dyed product.

[0106] According to the data of Example 1, Examples 11 to 13 and Comparative Examples 7 to 8, the conversion rate of the dyeing accelerator gradually increases with the increase of the reaction temperature. However, since the CH bonds on the double bonds of the monomers DMDAABr and AGE molecules are relatively active, the more active free radicals can easily replace hydrogen atoms and cause chain transfer. In addition, the activation of chain transfer is greater than the activation energy of chain growth. When the temperature is excessively increased, the conversion rate of the monomer is not greatly improved, but violent polymerization occurs, which reduces the color fixation rate and color fastness of the dyed product.

[0107] According to the data of Examples 1 and 15 to 17, in the initial stage of the polymerization reaction, the active free radicals of the initiator are more, the polymer molecular chain grows faster, and the conversion rate of the monomer increases significantly; when the reaction reaches a certain time, the active free radicals that can trigger chain growth decrease, the polymer molecular chain growth rate decreases, and the reaction tends to be stable. Prolonging the reaction time will only increase production costs.

[0108] For different dyes, the fixation rates before and after the addition of the dyeing accelerator were tested. The test results are shown in Table 2.

[0109] Table 2

[0110]

[0111] According to the data in Table 2, adding a dyeing accelerator during the dyeing process can significantly improve the fixation rate. The self-developed dyeing accelerator is a polymer with a quaternary ammonium salt cationic group and an epoxy group. It can react with the anion of the active dye with the help of the quaternary ammonium salt cationic group, and react with the cellulose fiber with the help of the epoxy group, thereby playing a "bridging" role between the dye molecules and the fiber molecules, allowing the unfixed dye and the hydrolyzed dye to continue to react with the fiber. Therefore, the fixation rate of the dye is significantly improved.

[0112] Although embodiments of the present invention have been shown and described, it will be appreciated by those skilled in the art that various changes, modifications, substitutions and variations may be made to the embodiments without departing from the principles and spirit of the present invention, and that the scope of the present invention is defined by the appended claims and their equivalents.

Claims

1. A dyeing accelerator, characterized in that: The molecular formula of the dyeing accelerator is shown in Formula I: Wherein, the molecular weight of the dyeing accelerator is 4×10 5 ~6×10 5 , the ratio of n to m is 1:

1.

2. A method for preparing the dyeing accelerator according to claim 1, characterized in that: Dimethyldiallylammonium bromide and allyl glycidyl ether are used as reaction monomers, an initiator is added, and a free radical polymerization reaction is carried out to obtain the dyeing accelerator.

3. The method for preparing a dyeing accelerator according to claim 2, characterized in that: The following steps are involved: a. Fully dissolving the dimethyldiallylammonium bromide in distilled water to obtain a first solution; Fully dissolving the allyl glycidyl ether in ethanol to obtain a second solution; b. Add the first solution into a four-necked flask, and introduce nitrogen to maintain the four-necked flask in a nitrogen positive pressure state; c. Add the second solution and the initiator dropwise into the first solution to obtain a reaction solution, perform a free radical polymerization reaction, and cool the temperature to room temperature to obtain the dyeing accelerator.

4. The method for preparing a dyeing accelerator according to claim 3, characterized in that: In step c, the total monomer concentration of dimethyldiallylammonium bromide and allyl glycidyl ether in the reaction solution is 20-40%.

5. The method for preparing a dyeing accelerator according to claim 3, characterized in that: In step c, the amount of the initiator added is 0.4-1.1% of the reaction solution.

6. The method for preparing a dyeing accelerator according to claim 3, characterized in that: In step c, the mass ratio of dimethyldiallylammonium bromide to allyl glycidyl ether in the reaction solution is 2 to 5:

1.

7. The method for preparing a dyeing accelerator according to claim 3, characterized in that: In step c, the temperature of the free radical polymerization reaction is 60 to 90° C., and the time of the free radical polymerization reaction is 4 to 8 hours.

8. The method for preparing a dyeing accelerator according to claim 3, characterized in that: In step c, the initiator is selected from sodium persulfate or ammonium persulfate.

9. The method for preparing a dyeing accelerator according to claim 3, characterized in that: In step c, the second solution and the initiator are added dropwise for 1.5 to 2.5 hours.

10. Use of the dyeing accelerator according to claim 1 or the dyeing accelerator according to any one of claims 2 to 9 in dyeing with reactive dyes.

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