Preparation method of salt-resistant leveling agent for dyeing of polyester fabric

Abstract

The present invention relates to the field of textile auxiliaries, and discloses a preparation method of a salt-resistant leveling agent for dyeing polyester fabrics. First, p-alkyl benzoate polyoxyethylene ether is prepared by condensing and adding ethylene oxide to p-hydroxybenzoic acid alkyl ester, and then it is compounded with ammonium tristyrylphenol polyoxyethylene ether sulfate to obtain a salt-resistant high-temperature leveling agent for polyester. The high-temperature leveling agent prepared by the present invention can effectively solve the dyeing problems such as color streaks caused by high water hardness and high conductivity in actual production.

Description

Technical Field

[0001] The present invention relates to the field of textile auxiliaries, and particularly to a preparation method of a salt-resistant leveling agent for dyeing polyester fabrics. Background Art

[0002] During the dyeing process of polyester fabrics, due to improper operation or incomplete removal of oil during the pretreatment of the fabrics, defects such as color streaks, color difference, and stripe patterns will occur, causing economic losses to the factory. During the dyeing process of polyester fabrics, dyes approach the polyester fibers and are adsorbed on the surface of the polyester fibers. As the temperature gradually increases during the dyeing process, most of the disperse dyes gradually diffuse from the surface of the polyester fibers into the fiber interior. Since the proportion of the amorphous region of polyester fibers gradually increases at high temperatures, the disperse dyes enter the amorphous region of the fibers and are fixed on the fibers, completing the dyeing of the polyester fibers by the disperse dyes (i.e., the process of the disperse dyes being adsorbed). At the same time, there is also a desorption process for the disperse dyes, that is, the disperse dyes gradually migrate from the fiber interior to the outside and finally transfer from the surface of the polyester fibers to the dye liquor. The above two processes of adsorption and desorption exist simultaneously, and the optimal dyeing state is that the two processes are in a dynamic equilibrium state. However, as the dyeing temperature increases, the dynamic equilibrium begins to be broken, that is, the adsorption trend gradually increases while the desorption trend gradually weakens, and the disperse dyes no longer redistribute after being adsorbed on the polyester fibers, thus easily causing defects such as color spots, color streaks, and color difference on the polyester fibers. The addition of a high-temperature leveling agent helps to reduce the occurrence of these dyeing problems. However, at present, many dyeing factories use recycled water for dyeing. The calcium and magnesium ions, electrolytes, etc. in the recycled water not only increase the probability of color spots and color streaks but also have a great impact on the dyeing performance of the leveling agent itself. Summary of the Invention

[0003] The technical problem to be solved by the present invention is to overcome the defects existing in the above-mentioned prior art and provide a preparation method of a salt-resistant leveling agent for dyeing polyester fabrics.

[0004] To achieve the above object, the present invention adopts the following technical solutions:

[0005] A: By mass ratio, add 200 - 300 parts of alkyl p-hydroxybenzoate and 4 - 6 parts of potassium hydroxide into a reaction vessel, start heating and stirring. When the temperature rises to 105 - 120 °C, start vacuuming, and remove water for 1 - 2 h under a vacuum degree of 1 - 10 kPa; then introduce 300 - 600 parts of ethylene oxide, and keep the temperature at 125 - 140 °C and the pressure at 0.25 - 0.35 MPa for heat preservation reaction for 2 - 5 h to obtain alkyl p-benzoate polyoxyethylene ether, and its structural general formula is as follows:

[0006]

[0007] B: Add 30 - 50 parts of alkyl p - benzoate polyoxyethylene ether, 5 - 15 parts of ammonium tristyrylphenol polyoxyethylene ether sulfate, and 10 - 30 parts of solvent into a reaction vessel equipped with a condensing reflux device. Start stirring, and after mixing evenly, slowly add 10 - 30 parts of deionized water. After stirring evenly, a salt - resistant leveling agent for polyester dyeing is prepared.

[0008] Preferably, the alkyl p - hydroxybenzoate is one of octyl p - hydroxybenzoate and decyl p - hydroxybenzoate; the number of oxyethylene (-CH2CH2O-) chain segments in the ammonium tristyrylphenol polyoxyethylene ether sulfate structure is 10 - 15, and the solvent is one of isopropyl alcohol, ethylene glycol monobutyl ether, and diethylene glycol monobutyl ether.

[0009] Due to the application of the above - mentioned technical solution, the present invention has the following advantages:

[0010] Using alkyl p - hydroxybenzoate as the initiator to condense and add ethylene oxide to prepare alkyl p - benzoate polyoxyethylene ether. The alkyl benzoate structure in this product has a certain similarity to the polyester structure of polyester, which can improve the adsorption of the surfactant by the fiber; at the same time, the spherical micelle formed by the long - chain alkane and the benzene ring in the structure has a larger internal space compared with the spherical micelle formed by a single long - chain alkane, and can solubilize more dye molecules inside the micelle, compensating for the decrease in the micelle solubilization ability caused by the presence of calcium and magnesium ions and electrolytes. Embodiment

[0011] The present invention will be further described below through specific embodiments. Example

[0012] (1) According to the mass ratio, add 250 kg of octyl p - hydroxybenzoate and 5 kg of potassium hydroxide into a reaction vessel. Start heating and stirring. When the temperature rises to 110 °C, start vacuuming, and remove water for 2 h under a vacuum degree of 6.3 kPa; then introduce 440 kg of ethylene oxide, and keep the reaction at 130 °C and 0.3 MPa for 3 h to obtain octyl p - benzoate polyoxyethylene ether.

[0013] (2) Add 35 kg of octyl p - benzoate polyoxyethylene ether, 10 kg of ammonium tristyrylphenol polyoxyethylene ether sulfate with 15 oxyethylenes, and 20 kg of isopropyl alcohol into a reaction vessel equipped with a condensing reflux device. Start stirring, and after mixing evenly, slowly add 30 kg of deionized water. After stirring evenly, a salt - resistant leveling agent for polyester dyeing is prepared. Example

[0014] (1) Weigh the ingredients by mass. Add 278 kg of decyl p-hydroxybenzoate and 5.5 kg of potassium hydroxide into a reaction vessel. Start heating and stirring. When the temperature reaches 115°C, turn on the vacuum. Remove water for 2 h under a vacuum of 6.3 kPa. Then introduce 484 kg of ethylene oxide and keep the reaction at 130°C and 0.3 MPa for 3.5 h to obtain decyl benzoate polyoxyethylene ether.

[0015] (2) Add 40 kg of decyl benzoate polyoxyethylene ether, 10 kg of ammonium sulfate of triphenylvinylphenol polyoxyethylene ether with 15 ethylene oxides, and 25 kg of isopropanol into a reaction vessel equipped with a condensation reflux device. Start stirring. After mixing evenly, slowly add 25 kg of deionized water and stir evenly to prepare a salt-tolerant leveling agent for polyester dyeing. Example

[0016] (1) Weigh the ingredients by mass. Add 278 kg of decyl p-hydroxybenzoate and 5.5 kg of potassium hydroxide into a reaction vessel. Start heating and stirring. When the temperature reaches 115°C, turn on the vacuum. Remove water for 2 h under a vacuum of 6.3 kPa. Then introduce 440 kg of ethylene oxide and keep the reaction at 130°C and 0.3 MPa for 3.5 h to obtain decyl benzoate polyoxyethylene ether.

[0017] (2) Add 45 kg of decyl benzoate polyoxyethylene ether, 5 kg of ammonium sulfate of triphenylvinylphenol polyoxyethylene ether with 15 ethylene oxides, and 20 kg of isopropanol into a reaction vessel equipped with a condensation reflux device. Start stirring. After mixing evenly, slowly add 30 kg of deionized water and stir evenly to prepare a salt-tolerant leveling agent for polyester dyeing.

[0018] Application evaluation:

[0019] Dye dispersibility

[0020] Test the dye dispersibility in tap water, hard water (water hardness 100 ppm), and electrolyte water (sodium sulfate 15 g / L) according to the test method described in the industry standard HG / T 4261-2011 "Textile dyeing and finishing auxiliaries - Leveling agents for polyester - Determination of high-temperature dispersibility". Rate according to the aggregation of residual dye particles on the filter paper. The specific description is as follows:

[0021] Grade 5 - No dye particle aggregation;

[0022] Grade 4 - Slight dye particles;

[0023] Grade 3 - Dye particles;

[0024] Grade 2 - Obvious dye particle aggregation;

[0025] Level 1 - The aggregation of dye particles is extremely obvious

[0026] The test results are shown in Table 1

[0027] Table 1 Test results of dye dispersibility

[0028]

[0029] It can be seen from the dispersibility test results in Table 1 that without the leveling agent, the dispersibility of the three dyes in tap water is level 2. When calcium and magnesium ions or electrolytes are present in the water, the aggregation of the dyes is aggravated and the dispersibility becomes worse. After adding the leveling agent of this embodiment, under the conditions of the presence of calcium and magnesium ions and electrolytes, the dye dispersibility drops by about 1 level, indicating that this embodiment has good dye dispersibility in different water quality environments

[0030] Migration property

[0031] The migration property was tested in tap water, hard water (water quality hardness 100 ppm), and electrolyte water (sodium sulfate 15 g / L) in accordance with the industry standard HG / T 4263-2011 "Determination of the migration property of leveling agents for polyester in textile dyeing and finishing auxiliaries". The blank control was without the leveling agent, and the experimental results are shown in Table 2

[0032] Table 2 Comparison of migration rates under different water quality conditions

[0033]

[0034] It can be clearly seen from the data in Table 2 that when electrolytes are present, the migration property of the dyes decreases significantly. When the leveling agent is present in the system, not only is the migration rate high, but also a high migration property is maintained under the water quality conditions of hard water and electrolytes. The above data comprehensively show that the high-temperature leveling agent of the present invention still has good application performance when calcium and magnesium ions and electrolytes are present in water

[0035] The technical scope of the present invention is not limited to the content described above. Those skilled in the art can make various deformations and modifications to the above embodiments without departing from the technical idea of the present invention, and these deformations and modifications should all fall within the scope of the present invention

Claims

1. A preparation method of a salt-resistant leveling agent for dyeing polyester fabrics, characterized in that The steps are as follows: A: Weigh according to parts by mass. Add 200 - 300 parts of alkyl p - hydroxybenzoate and 4 - 6 parts of potassium hydroxide into a reaction vessel. Start heating and stirring. When the temperature rises to 105 - 120 °C, start vacuuming. Remove water for 1 - 2 h under the condition of a vacuum degree of 1 - 10 kPa. Then introduce 300 - 600 parts of ethylene oxide and keep the temperature at 125 - 140 °C and the pressure at 0.25 - 0.35 MPa for heat - preservation reaction for 2 - 5 h to obtain alkyl p - benzoate polyoxyethylene ether, and its structural general formula is as follows: B: Add 30 - 50 parts of alkyl p - benzoate polyoxyethylene ether, 5 - 15 parts of ammonium tristyrylphenol polyoxyethylene ether sulfate, and 10 - 30 parts of a solvent into a reaction vessel equipped with a condensing reflux device. Start stirring. After mixing evenly, slowly add 10 - 30 parts of deionized water. Stir evenly to prepare a salt - resistant leveling agent for polyester dyeing. The solvent is one of isopropyl alcohol, ethylene glycol monobutyl ether, and diethylene glycol monobutyl ether.

2. The preparation method of a salt-resistant leveling agent for dyeing polyester fabrics according to claim 1, characterized in that: The alkyl p - hydroxybenzoate is one of octyl p - hydroxybenzoate and decyl p - hydroxybenzoate; the number of oxyethylene (-CH2CH2O-) chain segments in the structure of ammonium tristyrylphenol polyoxyethylene ether sulfate is 10 - 15.

3. A salt-resistant high-temperature leveling agent for polyester, characterized in that: Obtained by the preparation method according to any one of claims 1 - 2.

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