CN115197361B - Acrylic ester polymer tanning agent and preparation method thereof - Google Patents

Abstract

The application relates to the technical field of chemical tanning, and discloses an acrylic polymer tanning agent and a preparation method thereof, wherein the preparation method comprises the following steps: s1, dropwise adding cyanuric chloride into acetoacetate ethylene glycol methacrylate in the presence of a first reaction solvent, and reacting to obtain a cyanuric chloride derivative; s2, dropwise adding an acrylic ester monomer and a vinyl sulfonate monomer into the cyanuric chloride derivative in the presence of a second reaction solvent to obtain a premix; s3, dropwise adding an initiator and a molecular weight regulator into the premix under the participation of a third reaction solvent to carry out solution polymerization, and removing the reaction solvent to obtain the tanning agent. The acrylic ester polymer tanning agent without carboxyl is prepared, has a plurality of active binding points and is easy to combine with amino groups of the leather collagen fiber to form a crosslinked network structure. The shrinkage temperature can reach more than 90 ℃, and the tanning effect is good. In addition, the polymeric tanning agent can endow leather with good fullness and elasticity.

Description

Acrylic ester polymer tanning agent and preparation method thereof

Technical Field

The application relates to the technical field of chemical tanning, in particular to an acrylic polymer tanning agent and a preparation method thereof.

Background

Retanning is one of the most important processes in the leather production process. With the development of the leather industry, higher requirements are put on the color, quality, softness, fullness, elasticity, bleaching, light resistance and the like of leather. The traditional chrome tanning agent can not meet the requirements of high-grade leather. Therefore, retanning is generally considered important by tanning chemists at home and abroad. This is because the re-kneading can affect the properties of the leather in many ways, improving the look and feel and the internal quality of the leather.

The principle of the acrylic acid polymer as leather retanning agent is that carboxyl of acrylic acid is utilized to form coordination bond with chromium on chrome tanned leather, so that the leather is plump and astringent. Acrylate polymers are used in leather as a filler material to impart fullness to the leather. However, since the acrylate polymer has no binding functional group, it is easily removed by washing with water. Therefore, it is necessary to use the copolymer in combination with acrylic acid or a monomer having a carboxyl group to provide excellent adhesion.

Cyanuric chloride derivatives have been reported in a large number of patents and literature as leather tanning agents, and various types of derivatives are prepared mainly by utilizing the activity difference of different chlorine atoms on cyanuric chloride structures. Wherein the first chlorine atom can be substituted with active hydrogen such as amino group at 0-5 ℃ to prepare the derivative. The second chlorine atom can be substituted at 40-50 ℃ and can be further reacted to obtain the leather tanning agent.

< patent document >

Patent document CN106674141a

The patent utilizes the reaction of first chlorine atom of cyanuric chloride and active compound containing hydrophilic group to introduce sulfonic acid group or carboxylic acid group, and utilizes second chlorine atom to react with p-hydroxybenzaldehyde so as to prepare cyanuric chloride derivative. The derivative has aldehyde group and sulfonic acid group (carboxyl) to tan the softened acid skin, and the tanning principle is that the aldehyde group and the skin collagen form covalent bond combination, the sulfonic acid group (or carboxyl) and the skin collagen amino form ionic bond combination, and the leather shrinkage temperature after tanning is 76 ℃ at most, belongs to single-point combination and does not reach a crosslinking structure.

Patent document two CN108085434A

The polyurethane is adopted to control the molar ratio of the polyurethane to cyanuric chloride to prepare derivatives with cyanuric chloride at two ends, and the tanning principle of the derivatives is that the second chlorine atom on cyanuric chloride at two ends and collagen amino form a covalent bond structure to achieve the purpose of crosslinking, so that the shrinkage temperature of tanned leather can be increased to 86 ℃ at most. The disadvantage is that the cross-linking of the linear structure must be effected between two collagen fibers.

Moreover, the cyanuric chloride derivatives disclosed in the above patents are all small molecular compounds, and the leather is flat and thin after tanning.

Disclosure of Invention

< technical problem to be solved by the application >

The method is used for solving the problems that the shrinkage temperature is not high enough after the cyanuric chloride derivative is tanned as a leather tanning agent and the finished leather is shrunken.

< technical scheme adopted by the application >

Aiming at the technical problems, the application aims to provide an acrylic polymer tanning agent and a preparation method thereof. According to the application, cyanuric chloride is introduced into an acrylic ester polymer structure to prepare the acrylic ester polymer tanning agent without carboxyl. The tanning agent has a plurality of active binding points, and is easy to combine with amino groups of the collagen fibers to form a crosslinked network structure. The shrinkage temperature can reach more than 90 ℃, and the tanning effect is good. In addition, the polymeric tanning agent can endow leather with good fullness and elasticity.

The specific contents are as follows:

first, the application provides a preparation method of an acrylic polymer tanning agent, which comprises the following steps:

s1, dropwise adding cyanuric chloride and an acid binding agent into acetoacetate ethylene glycol methacrylate in the presence of a first reaction solvent, and reacting to obtain a cyanuric chloride derivative;

s2, dropwise adding an acrylic ester monomer and 2-acrylamide-2-methylpropanesulfonic acid into the cyanuric chloride derivative in the presence of a second reaction solvent to obtain a premix; and in the presence of a third reaction solvent, dropwise adding an initiator and a molecular weight regulator into the premix to carry out solution polymerization, and removing the reaction solvent to obtain the tanning agent.

Secondly, the application provides the acrylic ester polymer tanning agent prepared by the preparation method.

< technical mechanism and advantageous effects of the application >

The application prepares the cyanuric chloride derivative with carbon-carbon double bond by utilizing the reaction of active hydrogen between beta-dicarbonyl groups in acetoacetic acid ethylene glycol methacrylate structure and cyanuric chloride.

The cyanuric chloride derivative prepared by the method and the acrylic ester monomer are subjected to polymerization reaction to prepare the acrylic ester polymer, so that the tanned leather is endowed with good fullness and elasticity and good tearing strength.

The acrylic ester polymer tanning agent provided by the application has a plurality of cyanuric chloride structural sites, and can form a multi-point cross-linking network structure with leather collagen during tanning, so that higher shrinkage temperature is achieved.

Drawings

FIG. 1 is a diagram showing the mechanism of action of various tanning agents with leather collagen;

FIG. 2 is a diagram showing the mechanism of action of the acrylic polymer and the collagen.

Detailed Description

In order to make the objects, technical solutions and advantages of the embodiments of the present application more clear, the technical solutions of the embodiments of the present application will be clearly and completely described below. The specific conditions are not noted in the examples and are carried out according to conventional conditions or conditions recommended by the manufacturer. The reagents or apparatus used were conventional products commercially available without the manufacturer's attention.

First, the application provides a preparation method of an acrylic polymer tanning agent, which comprises the following steps:

s1, dropwise adding cyanuric chloride (TCT) and an acid binding agent into acetoacetate ethylene glycol methacrylate in the presence of a first reaction solvent, and reacting to obtain a cyanuric chloride derivative;

s2, dropwise adding an acrylic ester monomer and 2-acrylamide-2-methylpropanesulfonic acid into the cyanuric chloride derivative in the presence of a second reaction solvent to obtain a premix; and in the presence of a third reaction solvent, dropwise adding an initiator and a molecular weight regulator into the premix to carry out solution polymerization, and removing the reaction solvent to obtain the tanning agent.

In the application, in S1, the reaction temperature of acetoacetate-based ethylene glycol methacrylate and cyanuric chloride is 0-5 ℃, the dripping time is controlled to be 1-3 h, and the temperature is kept for 0.5-2 h after dripping.

In the application, in S3, the premix is heated to 25-30 ℃ for dripping, stirring treatment is carried out during dripping, the dripping time is controlled to be 2-5 h, and after dripping, the temperature is kept for 0.5-2 h.

In the application, the mole ratio of cyanuric chloride to acetoacetyl ethylene glycol methacrylate to acrylic ester monomer to 2-acrylamido-2-methylpropanesulfonic acid is 1 (2.0-2.2) (4.26-10.17) (1.98-2.15).

In the application, the addition amount of acetoacetic acid ethylene glycol methacrylate, cyanuric chloride, acrylic ester monomer and vinyl sulfonate monomer is taken as the total mass, and the use amount of the initiator is 10-20% of the total mass; and/or the molecular weight regulator is used in an amount of 2-5% of the total mass.

In the present application, the acrylate monomer includes at least one of Butyl Acrylate (BA), ethyl methacrylate, and Ethyl Acrylate (EA).

In the application, the initiator is an oxidation-reduction initiator and consists of dibenzoyl peroxide and N, N-dimethylaniline; and/or the molecular weight regulator is dodecyl mercaptan.

In the application, the first reaction solvent is acetone; the second reaction solvent and the third reaction solvent are both N, N-dimethylacetamide.

In the application, in S1, the acid-binding agent is triethylamine or sodium hydroxide, and the dosage of the acid-binding agent is 1.2-1.5 times of the molar quantity of cyanuric chloride;

when in use, the acid binding agent is prepared into a solution, specifically a triethylamine acetone solution or a sodium hydroxide aqueous solution.

In the application, in S1, acetoacetate group ethylene glycol methacrylate and cyanuric chloride are dissolved in a first reaction solvent to obtain corresponding solutions, and then the corresponding solutions are reacted;

the molar concentration of the acetoacetate-based ethylene glycol methacrylate solution is 1.17-2.34 mmol/mL;

and/or the number of the groups of groups,

s2, adding acetoacetic acid ethylene glycol methacrylate, cyanuric chloride, acrylate monomers and 2-acrylamide-2-methylpropanesulfonic acid into the mixture to obtain the total mass, wherein the adding amount of the second reaction solvent is 0.79-1.16 times of the total mass;

and/or the number of the groups of groups,

and S3, dissolving an initiator in a third reaction solvent to obtain a corresponding solution, and then carrying out reaction.

The molar concentration ranges of the dibenzoyl peroxide solution and the N, N-dimethylaniline solution are respectively 1.03-1.65 mmol/mL and 2.06-3.30 mmol/mL.

Secondly, the application provides the acrylic ester polymer tanning agent obtained by the preparation method.

< route of synthetic principle >

The synthetic route of the polyacrylic acid polymer tanning agent provided by the method is as follows:

wherein a, b, c, d is an integer, and n is a positive integer.

< mechanism of action of tanning agent and leather collagen fiber >

The mechanism of action of tanning agent and collagen in the prior art is shown in figure 1;

the mechanism of action of the polyacrylic acid polymer tanning agent and collagen provided by the application is shown in figure 2. R shown in fig. 2, which is a repeating unit structure. The method comprises the following steps:

figure 1 illustrates the range of leather shrinkage temperatures after tanning with various tanning agents relative to the range of hide shrinkage temperatures. From the wet heat resistance temperature of the pelts and the finished leather obtained by the various tanning methods available today: the raw leather is 65 ℃, the oil tanning is 60-70 ℃, the vegetable tanning is 75-85 ℃, the formaldehyde tanning is 80-85 ℃, the aluminum tanning is 70-75 ℃, the zirconium tanning is 90-95 ℃, and the chrome tanning is more than 100 ℃ (Chen Wuyong, li Guoying. Tanning chemistry [ M ]. Third edition. Beijing: light industrial Press in China, 2011: 2-3). The chrome tanned leather can form a multi-point crosslinked structure in principle, so that the shrinkage temperature of the finished leather is high.

Based on this, and referring to fig. 2, it can be seen that the acrylic polymer tanning agent prepared by the method is similar to chrome tanning principle, and has multiple active chain segments, so that a cross-linked network structure is formed between the tanned fibers, thereby achieving the purpose of increasing the shrinkage temperature.

< example >

Example 1

(1) 156.82g (0.7321 mol) of AAEM and 157mL of acetone were added to the reaction vessel and mixed, the temperature was controlled at 0-5℃and 337.50g (containing 0.3660mol of TCT) of a saturated solution of TCT in acetone was slowly added dropwise, while 89mL of a solution of triethylamine in acetone having a molar concentration of 4.94mmol/mL was added dropwise. The dripping time is controlled to be 2.5 hours, and the temperature is kept for 1 hour after the dripping is finished.

(2) 200g (1.5604 mol) BA and 150g (0.7238 mol) AMPS were added to step (1), and 450ml HMAMAc was added. Stirring was started, the temperature was controlled at 25℃and simultaneously, 144mL of DMAc solution having a molar concentration of 1.65mmol/mL of BPO, 72mL of DMAc solution having a molar concentration of 3.30mmol/mL of DMA, 57mL of DMAc solution having a molar concentration of 0.99mmol/mL of dodecyl mercaptan were added dropwise, respectively, to conduct solution polymerization. The dripping time is controlled to be 3 hours, after the dripping is finished, the temperature is kept at 25 ℃ for 1 hour, and then spray drying is carried out to remove the solvent, so that a white powdery product is obtained, and the weight average molecular weight is determined to be 4529.

Example 2

(1) To the reaction vessel was added 153.34g (0.7158 mol) of AAEM and 157mL of acetone, mixed, and the temperature was controlled at 0-5℃and 300g (containing 0.3254mol of TCT) of a saturated solution of TCT in acetone was slowly added dropwise, while 79mL of a solution of triethylamine in acetone having a molar concentration of 4.94mmol/mL was added dropwise. The dripping time is controlled to be 2.0h, and the temperature is kept for 1h after the dripping is finished.

(2) 190g (1.4824 mol) BA and 140g (0.6755 mol) AMPS were added to step (1), and 420ml HMAMAC was added. The stirring was started, the temperature was controlled at 30℃and 136mL of DMAc solution having a molar concentration of 1.65mmol/mL of BPO, 68mL of DMAc solution having a molar concentration of 3.30mmol/mL of DMA and 54mL of DMAc solution having a molar concentration of 0.99mmol/mL of dodecyl mercaptan were simultaneously added dropwise, respectively, to conduct solution polymerization. The dripping time is controlled to be 3 hours, after the dripping is finished, the temperature is kept at 30 ℃ for 2 hours, and then the spray drying is carried out to remove the solvent, so that a white powdery product is obtained, and the weight average molecular weight is measured to be 6953.

Example 3

(1) 156.82g (0.7321 mol) of AAEM and 157mL of acetone were added to the reaction vessel and mixed, the temperature was controlled at 0-5℃and 337.5g (containing 0.3660mol of TCT) of a saturated solution of TCT in acetone was slowly added dropwise, while 96mL of a solution of triethylamine in acetone having a molar concentration of 4.94mmol/mL was added dropwise. The dripping time is controlled to be 3.0h, and the temperature is kept for 1h after the dripping is finished.

(2) 200g (1.5604 mol) BA and 150g (0.7238 mol) AMPS were added to step (1), and 450ml HMAMAc was added. The stirring was started, the temperature was controlled at 25℃and simultaneously, 230mL of DMAc solution having a molar concentration of 1.03mmol/mL of BPO, 115mL of DMAc solution having a molar concentration of 2.06mmol/mL of DMA and 57mL of DMAc solution having a molar concentration of 0.99mmol/mL of dodecyl mercaptan were added dropwise, respectively, to conduct solution polymerization. The dripping time is controlled to be 3 hours, after the dripping is finished, the temperature is kept at 25 ℃ for 1 hour, and then spray drying is carried out to remove the solvent, so that a white powdery product is obtained, and the weight average molecular weight is determined to be 5862.

Example 4

(1) 172.51g (0.8053 mol) of AAEM and 157mL of acetone were added to the reaction vessel and mixed, the temperature was controlled at 0-5℃and 337.5g (containing 0.3660mol of TCT) of a saturated solution of TCT in acetone was slowly added dropwise, while 112mL of a solution of triethylamine in acetone having a molar concentration of 4.94mmol/mL was added dropwise. The dripping time is controlled to be 3.0h, and the temperature is kept for 1h after the dripping is finished.

(2) 200g (1.5604 mol) BA and 150g (0.7238 mol) AMPS were added to step (1), and 450ml HMAMAc was added. Stirring was started, the temperature was controlled at 25℃and simultaneously 189mL of DMAc solution having a molar concentration of 1.03mmol/mL of BPO, 118mL of DMAc solution having a molar concentration of 2.06mmol/mL of DMA, 147mL of DMAc solution having a molar concentration of 0.99mmol/mL of dodecyl mercaptan were added dropwise, respectively, to conduct solution polymerization. The dripping time is controlled to be 3 hours, after the dripping is finished, the temperature is kept at 25 ℃ for 1 hour, and then the spray drying is carried out to remove the solvent, so that a white powdery product is obtained, and the weight average molecular weight is measured to be 7635.

Example 5

(1) 63.89g (0.2982 mol) of AAEM and 67mL of acetone were added to the reaction vessel and mixed, the temperature was controlled at 0-5℃and 125.0g (containing 0.1356mol of TCT) of a saturated solution of TCT in acetone was slowly added dropwise while 41mL of an aqueous solution of sodium hydroxide having a molar concentration of 4.94mol/mL was added dropwise. The dripping time is controlled to be 1.5h, and the temperature is kept for 1h after the dripping is finished.

(2) 100g (0.7802 mol) BA and 56g (0.2702 mol) AMPS were added to step (1), and 168ml HMAMAc was added. The stirring was started, the temperature was controlled at 25℃and 98mL of DMAc solution having a molar concentration of 1.38mmol/mL of BPO, 49mL of DMAc solution having a molar concentration of 2.75mmol/mL of DMA and 61mL of DMAc solution having a molar concentration of 1.24mmol/mL of dodecyl mercaptan were simultaneously added dropwise, respectively, to conduct solution polymerization. The dripping time is controlled to be 3 hours, after the dripping is finished, the temperature is kept at 25 ℃ for 1 hour, and then spray drying is carried out to remove the solvent, so that a white powdery product is obtained, and the weight average molecular weight is measured to be 5064.

Example 6

(1) 67.38g (0.3145 mol) AAEM and 67mL acetone were added to the reaction vessel and mixed, the temperature was controlled at 0-5℃and 145.0g (containing 0.1573mol of TCT) of a saturated solution of TCT in acetone was slowly added dropwise, while 38mL of a solution of triethylamine in acetone having a molar concentration of 4.94mmol/mL was added dropwise. The dripping time is controlled to be 1.5h, and the temperature is kept for 1h after the dripping is finished.

(2) 200g (1.5604 mol) BA, 67.5g (0.3257 mol) AMPS were added to step (1), and 202.5ml HMAMAc was added. The stirring was started, the temperature was controlled at 25℃and, at the same time, 91mL of DMAc solution having a molar concentration of 1.65mmol/mL of BPO, 46mL of DMAc solution having a molar concentration of 3.30mmol/mL of DMA and 36mL of DMAc solution having a molar concentration of 0.99mmol/mL of dodecyl mercaptan were added dropwise, respectively, to conduct solution polymerization. The dripping time is controlled to be 3 hours, after the dripping is finished, the temperature is kept at 25 ℃ for 1 hour, and then the spray drying is carried out to remove the solvent, so that a white powdery product is obtained, and the weight average molecular weight is measured to be 4921.

Example 7

(1) To the reaction vessel, 74.11g (0.3460 mol) AAEM and 74mL acetone were added and mixed, the temperature was controlled at 0-5℃and 145g (containing 0.1573mol of TCT) of TCT acetone saturated solution was slowly added dropwise, while 44mL of triethylamine acetone solution having a molar concentration of 4.94mmol/mL was added dropwise. The dripping time is controlled to be 1.5h, and the temperature is kept for 1h after the dripping is finished.

(2) To step (1) were added 205g (1.5994 mol) BA, 70g (0.3378 mol) AMPS, and 210ml HMAMAC was added. The stirring was started, the temperature was controlled at 25℃and simultaneously, 95mL of DMAc solution having a molar concentration of 1.65mmol/mL of BPO, 47mL of DMAc solution having a molar concentration of 3.30mmol/mL of DMA and 76mL of DMAc solution having a molar concentration of 0.99mmol/mL of dodecyl mercaptan were added dropwise, respectively, to conduct solution polymerization. The dripping time is controlled to be 3 hours, after the dripping is finished, the temperature is kept at 30 ℃ for 1 hour, and then spray drying is carried out to remove the solvent, so that a white powdery product is obtained, and the weight average molecular weight is measured to be 6875.

Example 8

(1) 70.74 g (0.3302 mol) AAEM and 71mL acetone were added to the reaction vessel and mixed, the temperature was controlled at 0-5℃and 145g (containing 0.1573mol of TCT) of a saturated solution of TCT in acetone was slowly added dropwise, while 38.2mL of a solution of triethylamine in acetone having a molar concentration of 4.94mmol/mL was added dropwise. The dripping time is controlled to be 1.5h, and the temperature is kept for 1h after the dripping is finished.

(2) To step (1) were added 205g (1.5994 mol) BA, 70g (0.3378 mol) AMPS, and 210ml HMAMAC was added. Stirring was started, the temperature was controlled at 25℃and simultaneously, 150mL of DMAc solution having a molar concentration of 1.03mmol/mL of BPO, 75mL of DMAc solution having a molar concentration of 2.06mmol/mL of DMA, 94mL of DMAc solution having a molar concentration of 0.99mmol/mL of dodecyl mercaptan were added dropwise, respectively, to conduct solution polymerization. The dripping time is controlled to be 4 hours, after the dripping is finished, the temperature is kept at 25 ℃ for 1 hour, and then spray drying is carried out to remove the solvent, so that a white powdery product is obtained, and the weight average molecular weight is determined to be 8531.

< test example >

The sheepskin pelts were tested for the samples in examples 1-8 and comparative example 1 (Granofin F-90 of Style).

The experimental treatment steps are as follows: the method comprises the steps of soaking the sheep skin bare skin, liming, deashing, softening and tanning, wherein the material consumption is calculated according to the weight of the sheep skin. The tanning process is shown in table 1 below.

Table 1 tanning process

The experimental results after the treatment by the process described in table 1 are shown in table 2.

Table 2 tanning results

Tanning agent	Shrinkage temperature/°c	Hand feel	Tensile Strength/Mpa	Tear Strength/N.mm-1
					Example 1	95	Q bullet, full	286.32	81.58
Example 2	95	Q bullet, full	297.36	82.54
					Example 3	90	Q bullet, full	256.25	78.49
Example 4	98	Q bullet, full	380.28	86.68
					Example 5	93	Q bullet, full	276.45	79.35
Example 6	93	Q bullet, full	272.22	78.96
					Example 7	91	Q bullet, full	260.37	80.65
Example 8	96	Q bullet, full	301.12	83.79
					Comparative example 1	77	Soft and dry	305.8	53.64

As can be seen from the data in table 2, the organic tanning agent prepared by the application can directly tan pelts to prepare leather, so that the tanned leather has full and elastic hand feeling.

The above description is only of the preferred embodiments of the present application and is not intended to limit the present application, but various modifications and variations can be made to the present application by those skilled in the art. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present application should be included in the protection scope of the present application.

Claims (7)

1. The preparation method of the acrylic polymer tanning agent is characterized by comprising the following steps:

s1, dropwise adding cyanuric chloride and an acid binding agent into acetoacetate ethylene glycol methacrylate in the presence of a first reaction solvent, and reacting to obtain a cyanuric chloride derivative;

s2, dropwise adding an acrylic ester monomer and 2-acrylamide-2-methylpropanesulfonic acid into the cyanuric chloride derivative in the presence of a second reaction solvent to obtain a premix; dropwise adding an initiator and a molecular weight regulator into the premix to carry out solution polymerization in the presence of a third reaction solvent, and removing the reaction solvent to obtain a tanning agent;

in the S1, the reaction temperature of acetoacetate-based ethylene glycol methacrylate and cyanuric chloride is 0-5 ℃, the dripping time is controlled to be 1-3 hours, and after dripping is finished, the temperature is kept for 0.5-2 hours;

s2, heating the premix to 25-30 ℃, dropwise adding, controlling the dropwise adding time to be 2-5 h, and preserving heat for 0.5-2 h after dropwise adding;

the molar ratio of cyanuric chloride to acetoacetyl ethylene glycol methacrylate to acrylate monomer to 2-acrylamido-2-methylpropanesulfonic acid is 1 (2.0-2.2) (4.26-10.17) (1.98-2.15).

2. The preparation method of the acrylic polymer tanning agent according to claim 1, wherein the addition amount of acetoacetate-based ethylene glycol methacrylate, cyanuric chloride, acrylic monomer and vinyl sulfonate monomer is taken as the total mass, and the amount of the initiator is 10-20% of the total mass; and/or the dosage of the molecular weight regulator accounts for 2-5% of the total mass.

3. The method for preparing an acrylic polymer tanning agent according to claim 1, wherein in S2, the reaction solvent is removed by spray drying.

4. The method for preparing the acrylic polymer tanning agent according to claim 1, wherein the initiator is a redox initiator, and consists of dibenzoyl peroxide and N, N-dimethylaniline; and/or the molecular weight regulator is dodecyl mercaptan.

5. The method for preparing an acrylic polymer tanning agent according to claim 1, wherein in S1, the first reaction solvent is acetone;

and/or the number of the groups of groups,

in S1, the acid-binding agent is triethylamine or sodium hydroxide, and the dosage of the acid-binding agent is 1.2-1.5 times of the molar quantity of cyanuric chloride;

and/or the number of the groups of groups,

the second reaction solvent and the third reaction solvent are both N, N-dimethylacetamide or isopropanol.

6. The method for preparing the acrylic polymer tanning agent according to claim 1 or 5, wherein,

s1, dissolving acetoacetate-based ethylene glycol methacrylate and cyanuric chloride in a first reaction solvent to obtain corresponding solutions, and then carrying out reaction;

the molar concentration of the acetoacetate-based ethylene glycol methacrylate solution is 1.17-2.34 mmol/mL;

and/or the number of the groups of groups,

s2, adding acetoacetic acid ethylene glycol methacrylate, cyanuric chloride, acrylate monomers and vinyl sulfonate monomers into the mixture to be the total mass, wherein the adding amount of the second reaction solvent is 0.79-1.16 times of the total mass;

and/or the number of the groups of groups,

and S3, dissolving an initiator in a third reaction solvent to obtain a corresponding solution, and then carrying out reaction.

7. An acrylic polymer tanning agent obtained by the preparation method according to any one of claims 1 to 6.