PAA-PVP-AMPS terpolymer based anti-staining soaping agent for cotton as well as preparation method and application of anti-staining soaping agent

Abstract

The invention relates to a PAA-PVP-AMPS terpolymer based anti-staining soaping agent for cotton as well as a preparation method and application of the PAA-PVP-AMPS terpolymer based anti-staining soaping agent. The anti-staining soaping agent comprises the following components in percentage by weight: 25-35% of a PAA-PVP-AMPS terpolymer aqueous solution, 5-12% of a bio-based nonionic surfactant, 4-8% of a green chelating agent, 2-5% of a low-foam penetrant and 40-64% of deionized water. And the PAA-PVP-AMPS terpolymer is formed by polymerizing acrylic acid, polyvinylpyrrolidone and 2-acrylamide-2-methyl propane sulfonic acid. According to the anti-staining soaping agent disclosed by the invention, PAA and PVP complexes are taken as main bodies, AMPS is taken as a third monomer, a PAA-PVP-AMPS ternary comb-shaped copolymer is constructed, the anti-staining effect and acid and alkali resistance are remarkably improved by cooperating with a bio-based nonionic surfactant, a green chelating agent and a low-foam penetrant, and the soaping agent is adaptive to a soaping process at 60-80 DEG C and is green and environment-friendly.

Description

Technical Field

[0001] This invention belongs to the field of chemical additives technology, specifically relating to a PAA-PVP-AMPS terpolymer-based anti-stain soaping agent for cotton, its preparation method, and its application. Background Technology

[0002] Reactive dyes are generally the first choice for dyeing and printing cotton fibers due to their advantages such as a full color spectrum, bright colors, and low cost. However, they have a fatal problem: they cannot be 100% fixed. ① During dyeing, about 20%-40% of the dye is not covalently bonded to the cotton fibers, forming unfixed dye. ② The reactive groups of the dye are easily hydrolyzed by water and alkali to form hydrolyzed dyes, which have similar adsorption properties to reactive dyes and are very easy to re-stain the fabric. ③ If the floating dye is not stably dispersed after soaping, it will be adsorbed again under high temperature and high salt conditions, causing staining of the white ground, color bleeding, and decreased color fastness, especially in dark-colored printing.

[0003] To address the aforementioned issues, soaping agents are primarily used to treat dyed fabrics. In recent years, existing technologies have mostly employed PAA (polyacrylic acid) or PAA-PVP binary complex systems. While these systems possess some dispersion and chelation capabilities, they exhibit significant drawbacks: First, they lack sufficient salt and alkali resistance, easily flocculating and reducing dispersion stability in high-salt (residual sodium sulfate) and high-alkali (pH 9-11) environments following reactive dyeing. Second, their dye coating and anti-staining effects are limited, with white-ground anti-staining grades often only reaching level 3, insufficient for high-end fabric requirements. Third, soaping requires high temperatures of 95-98℃, resulting in extremely high energy and water consumption, and some products contain harmful substances such as phosphorus and APEO, failing to meet environmental protection policy requirements. Therefore, these methods cannot fundamentally solve the problem.

[0004] Furthermore, some soap detergents have compatibility issues with dyeing and finishing auxiliaries (such as fixing agents and leveling agents), which can lead to problems such as color changes and a stiff feel. They are also sensitive to water hardness, with performance significantly reduced in water with high calcium and magnesium ion concentrations. Traditional soap detergents contain phosphorus and APEO (alkylphenol polyoxyethylene ether), which do not comply with current environmental policies and can cause eutrophication pollution of water bodies after discharge.

[0005] With the upgrading of quality in the textile industry, the market urgently needs an active anti-stain soap for cotton that combines high efficiency in preventing staining, strong weather resistance, low-temperature energy saving, and green environmental protection. Summary of the Invention

[0006] The purpose of this invention is to provide a PAA-PVP-AMPS terpolymer-based anti-stain soaping agent for cotton. It is based on a polyacrylic acid (PAA) and polyvinylpyrrolidone (PVP) complex, with 2-acrylamide-2-methylpropanesulfonic acid (AMPS) introduced as a third monomer to construct a PAA-PVP-AMPS terpolymer. This synergistic effect with bio-based nonionic surfactants, green chelating agents, and low-foaming penetrants significantly improves anti-staining performance and acid / alkali resistance. It is suitable for low-temperature soaping processes at 60-80℃ and is environmentally friendly.

[0007] The technical solution adopted by the present invention to solve the above problems is as follows: a PAA-PVP-AMPS terpolymer-based anti-stain soaping agent for cotton, comprising the following components by weight percentage: 25-35% aqueous solution of PAA-PVP-AMPS terpolymer Bio-based nonionic surfactants 5-12% Green chelating agent 4-8% Low-foaming penetrant 2-5% Deionized water 40-64% The solid content of the PAA-PVP-AMPS terpolymer aqueous solution is 30-40%; The PAA-PVP-AMPS terpolymer aqueous solution is polymerized from the following monomers in parts by weight: 25-40 parts of acrylic acid (AA), 10-20 parts of polyvinylpyrrolidone (PVP), and 8-15 parts of 2-acrylamide-2-methylpropanesulfonic acid (AMPS), wherein the K value of the polyvinylpyrrolidone is 30-60.

[0008] Preferably, the PAA-PVP-AMPS terpolymer is prepared by the following method: (1) Add deionized water to the reactor, heat to 75-85℃, and purge with nitrogen for protection; (2) Add AA monomer, PVP and initiator in sequence, and stir at constant temperature for 1.5-2h; then add a mixture of AMPS monomer and chain transfer agent dropwise, with the dropwise addition time controlled at 1-1.5h, and keep the reaction at the temperature for 2-3h after the dropwise addition is completed; cool down to below 40℃, and adjust the pH to 6.0-7.0 with sodium hydroxide solution to obtain an aqueous solution of PAA-PVP-AMPS terpolymer with a solid content of 30-40%.

[0009] More preferably, the initiator is ammonium persulfate, and its addition amount is 0.8-1.2% of the total monomer weight; the chain transfer agent is mercaptoacetic acid, and its addition amount is 0.3-0.5% of the total monomer weight.

[0010] Preferably, the bio-based nonionic surfactant is one or more of C8-C14 cocoyl alkyl glycoside (APG-0814), C8-C10 alkyl glycoside (APG-0810), and C12-C14 lauryl glycoside (APG-1214).

[0011] More preferably, the bio-based nonionic surfactant is a compound of C8-C14 cocoyl alkyl glycoside and C8-C10 alkyl glycoside in a weight ratio of 6-8:2-3, wherein the solid content of the C8-C14 cocoyl alkyl glycoside is 50% and the solid content of the C8-C10 alkyl glycoside is 50%.

[0012] Preferably, the green chelating agent is tetrasodium glutamate diacetate (GLDA-Na4) with a solid content of 40-47%.

[0013] Preferably, the low-foaming penetrant is isomeric C13 alcohol polyoxyethylene ether or isomeric tridecyl alcohol polyoxyethylene ether, wherein the ethylene oxide EO addition number of the isomeric tridecyl alcohol polyoxyethylene ether is 7-9.

[0014] Another object of the present invention is to provide a method for preparing a PAA-PVP-AMPS terpolymer-based anti-stain soaping agent for cotton, comprising the following steps: (1) At room temperature, add deionized water into a clean reaction vessel, turn on the stirrer, and add green chelating agent and bio-based nonionic surfactant in sequence, stirring until completely dissolved; (2) Add low-foaming penetrant and continue stirring; (3) Slowly add the PAA-PVP-AMPS terpolymer aqueous solution, stir until the system is uniform and transparent, and let it stand to defoam.

[0015] Preferably, the specific steps include: (1) At room temperature, add deionized water into a clean reaction vessel, turn on the stirrer, add green chelating agent and bio-based nonionic surfactant in sequence, and stir for 10-15 minutes until completely dissolved; (2) Add low-foaming penetrant and continue stirring for 5-10 minutes; (3) Slowly add the PAA-PVP-AMPS terpolymer aqueous solution, control the stirring speed to 200-300r / min, stir for 30-40min until the system is uniform and transparent, and let it stand to defoam.

[0016] Another objective of this invention is to provide an application of a PAA-PVP-AMPS terpolymer-based anti-staining soaping agent for cotton, wherein the active anti-staining soaping agent is used to soap and wash pure cotton reactive dyed fabrics. The soaping process conditions are: liquor ratio 1:15-25, soaping agent dosage 1.0-2.0 g / L, temperature 60-80℃, time 15-25 min, followed by two hot water washes and one cold water wash before drying.

[0017] Compared with the prior art, the advantages of the present invention are as follows: (1) Triple function synergy, excellent anti-staining and floating color removal effect: The white anti-staining level of the soap detergent of this invention can reach level 4-5, and the floating color removal rate is ≥93.1%, which is far superior to the existing PAA-PVP binary system. This invention uses PAA-PVP-AMPS ternary comb copolymer as the core functional component to achieve the integration of the triple function of "chelation-encapsulation-dispersion": AA provides carboxyl groups, which effectively chelate Ca in water. 2+ Mg 2+ Hard water ions prevent dyes from forming lakes with metal ions; the strong polar structure of PVP tightly coats hydrolyzed dyes and unfixed floating dyes through hydrogen bonds and hydrophobic interactions, preventing them from staining the fabric; the sulfonic acid groups (-SO3) introduced by AMPS... ⁻ It significantly enhances the anionicity and branching degree of the copolymer, improves its salt and alkali resistance and dispersion stability, and makes the coated dye complex stably suspended in the soap bath, making it easy to be washed out with water.

[0018] (2) Strong weather resistance and excellent adaptability to working conditions: The structural characteristics of the PAA-PVP-AMPS ternary comb copolymer of this invention enable the soaping agent to exhibit no flocculation or stratification under high-salt (sodium sulfate residue) and high-alkali (pH 9-11) soaping conditions, and it has excellent dispersion stability; and its hard water resistance is ≥300 ppm (with Ca 2+ (Calculated) It does not precipitate in hard water environments, has a stable anti-staining effect, and does not require the addition of water softener; in addition, it has excellent compatibility with auxiliaries such as fixing agents and leveling agents in the dyeing and finishing process, and has no problems such as color change or hardening of the hand, making it suitable for the actual working conditions of different printing and dyeing production lines.

[0019] (3) Low temperature energy saving and significant cost reduction: The PAA-PVP-AMPS ternary comb copolymer of this invention is suitable for medium and low temperature soaping process of 60-80℃, without the need for traditional high temperature heating of 95-98℃, and the soaping time is shortened to about 20 minutes. Only 2 hot water washes + 1 cold water wash are required afterward. Compared with the traditional process, the overall energy consumption is reduced by more than 28%, water consumption and labor time consumption are greatly reduced, the overall cost of industrial production is significantly reduced, and the application process is highly compatible with the existing printing and dyeing production line. No additional equipment modification is required, and it is easy to promote and apply.

[0020] (4) Green and environmentally friendly, in compliance with policy requirements: The PAA-PVP-AMPS ternary comb copolymer of this invention is phosphorus-free and APEO-free in its entire formula. The core chelating agent is bio-based GLDA-Na4, and the surfactant is a biodegradable alkyl glycoside. The 28-day biodegradation rate of the soap is over 85%, and there is no secondary pollution after discharge, thus avoiding eutrophication of water bodies.

[0021] (5) The preparation process is simple and easy to industrialize: The preparation of the soap detergent of the present invention is carried out at room temperature and medium and low temperature. No high temperature and high pressure equipment is required. The process steps are simple, the parameters are easy to control, and the product has good repeatability. The raw materials are all commercially available conventional chemical raw materials, which are easy to obtain and the cost is controllable, making them suitable for large-scale industrial production.

[0022] (6) Improve the color fastness of fabrics and ensure quality: Cotton fabrics treated with the soaping agent of this invention can achieve a dry rubbing fastness of grade 4 and a wet rubbing fastness of grade 3-4, which are better than existing traditional soaping agents. This effectively avoids the problems of color fading and staining in the subsequent use of the fabric, ensures the dyeing / printing quality of cotton fabrics, and meets the market demand for high-end fabrics. Detailed Implementation

[0023] The present invention will be further described in detail below with reference to the embodiments. Example 1

[0024] (1) Preparation of PAA-PVP-AMPS terpolymer Weigh out the following components by weight: 32 parts AA, 15 parts PVP (K value 40), 12 parts AMPS, 0.69 parts ammonium persulfate (1.0% of total monomer weight), 0.23 parts thioglycolic acid (0.35% of total monomer weight), and 80 parts deionized water. Add the deionized water to the reactor, heat to 80°C, and purge with nitrogen for protection. Add the AA monomer, PVP, and ammonium persulfate sequentially, and stir at a constant temperature for 1.8 hours. Then, add a mixture of AMPS and thioglycolic acid dropwise over 1.2 hours, and keep the mixture at the temperature for 2.5 hours after the addition is complete. Cool down to 35°C and adjust the pH to 6.5 with 10% sodium hydroxide solution to obtain an aqueous solution of PAA-PVP-AMPS terpolymer with a solid content of 35%.

[0025] (2) A PAA-PVP-AMPS terpolymer-based anti-stain soaping agent for cotton, comprising the following components by weight: PAA-PVP-AMPS terpolymer aqueous solution (35% solids content) 30.0%; APG-0814 (50% solids content, Transfar Group Co., Ltd.) 6.0%; APG-0810 (50% solids content, Transfar Group Co., Ltd.) 3.0%; GLDA-Na4 (47% solids content, Shandong Yuanlian Chemical) 4.0%; low-foaming penetrant 1307 (isomeric C13 alcohol ether EO7, BASF) 2.0%; deionized water 55.0%. It should be noted that APG-0814 and APG-0810 are commercially available products with 50% solids content, and the percentages in the formulation refer to the amount of the product added.

[0026] The preparation method of this active anti-stain soap for cotton includes the following steps: ① At room temperature, add deionized water to a clean reaction vessel, turn on the stirrer, and add the green chelating agent and bio-based nonionic surfactant in sequence, stirring for 10 minutes until completely dissolved; ② Add low-foaming penetrant and continue stirring for 10 minutes; ③ Slowly add the PAA-PVP-AMPS terpolymer aqueous solution, control the stirring speed at 300r / min, stir for 40min until the system is homogeneous and transparent, and let it stand to defoam. Example 2

[0027] (1) Preparation of PAA-PVP-AMPS terpolymer Weigh out the following components by weight: 30 parts AA, 18 parts PVP (K value 30), 10 parts AMPS, 0.61 parts ammonium persulfate (0.9% of the total monomer weight), 0.20 parts thioglycolic acid (0.30% of the total monomer weight), and 75 parts deionized water. Add the deionized water to the reactor, heat to 80°C, and purge with nitrogen for protection. Add the AA monomer, PVP, and ammonium persulfate sequentially, and stir at a constant temperature for 1.5 hours. Then, add a mixture of AMPS and thioglycolic acid dropwise over 1.2 hours, and maintain the temperature for 2.0 hours after the addition is complete. Cool down to 35°C and adjust the pH to 6.5 with 10% sodium hydroxide solution to obtain an aqueous solution of PAA-PVP-AMPS terpolymer with a solid content of 33%.

[0028] (2) A PAA-PVP-AMPS terpolymer-based anti-stain soaping agent for cotton, comprising the following components by weight: PAA-PVP-AMPS terpolymer aqueous solution (33% solids content) 28.0%; APG-0814 (50% solids content, Transfar Group Co., Ltd.) 7.0%; APG-0810 (50% solids content, Transfar Group Co., Ltd.) 3.0%; GLDA-Na4 (47% solids content, Shandong Yuanlian Chemical) 7.0%; low-foaming penetrant 1307 (isomeric C13 alcohol ether EO7, BASF) 4.0%; deionized water 51.0%.

[0029] The preparation method of this active anti-stain soap for cotton includes the following steps: ① At room temperature, add deionized water to a clean reaction vessel, turn on the stirrer, and add the green chelating agent and bio-based nonionic surfactant in sequence, stirring for 10 minutes until completely dissolved; ② Add low-foaming penetrant and continue stirring for 10 minutes; ③ Slowly add the PAA-PVP-AMPS terpolymer aqueous solution, control the stirring speed at 300r / min, stir for 40min until the system is homogeneous and transparent, and let it stand to defoam. Example 3

[0030] (1) Preparation of PAA-PVP-AMPS terpolymer Weigh out the following components by weight: 35 parts AA, 14 parts PVP (K value 50), 14 parts AMPS, 0.80 parts ammonium persulfate (1.2% of the total monomer weight), 0.33 parts thioglycolic acid (0.50% of the total monomer weight), and 85 parts deionized water. Add the deionized water to the reactor, heat to 85°C, and purge with nitrogen for protection. Add the AA monomer, PVP, and ammonium persulfate sequentially, and stir at a constant temperature for 1.5 hours. Then, add a mixture of AMPS and thioglycolic acid dropwise over a period of 1.5 hours. After the addition is complete, keep the reactor at this temperature for 3.0 hours. Cool down to 35°C and adjust the pH to 6.5 with 10% sodium hydroxide solution to obtain an aqueous solution of PAA-PVP-AMPS terpolymer with a solid content of 38%.

[0031] (2) A PAA-PVP-AMPS terpolymer-based anti-stain soaping agent for cotton, comprising the following components by weight: PAA-PVP-AMPS terpolymer aqueous solution (38% solids content) 32.0%; APG-0814 (50% solids content, Transfar Group Co., Ltd.) 5.0%; APG-0810 (50% solids content, Transfar Group Co., Ltd.) 2.0%; GLDA-Na4 (47% solids content, Shandong Yuanlian Chemical) 5.0%; low-foaming penetrant 1307 (isomeric C13 alcohol ether EO7, BASF) 3.0%; deionized water 53.0%.

[0032] The preparation method of this active anti-stain soap for cotton includes the following steps: ① At room temperature, add deionized water to a clean reaction vessel, turn on the stirrer, and add the green chelating agent and bio-based nonionic surfactant in sequence, stirring for 15 minutes until completely dissolved; ② Add low-foaming penetrant and continue stirring for 10 minutes; ③ Slowly add the PAA-PVP-AMPS terpolymer aqueous solution, control the stirring speed at 300r / min, stir for 40min until the system is homogeneous and transparent, and let it stand to defoam.

[0033] Comparative Example 1 (PAA-PVP binary system without AMPS) Compared to Example 1, the only difference is that AMPS is not added.

[0034] The “PAA-PVP-AMPS terpolymer aqueous solution” in the formula was replaced with an equal amount of PAA-PVP binary copolymer aqueous solution (AMPS monomer was not added during preparation, and the other polymerization conditions were the same as in Example 1, with the initiator and chain transfer agent added at the same weight percentage as the total monomers).

[0035] The remaining components and proportions of the soap detergent are the same as in Example 1.

[0036] Comparative Example 2 (Commercially available regular anti-stain soap) A commonly available anti-stain soap was used as a comparative example. The commonly available anti-stain soap, by weight, includes the following components: fatty alcohol polyoxyethylene ether (AEO-9): 12%, sodium fatty alcohol sulfate (SLES): 8%, sodium α-alkenyl sulfonate (AOS) 35%: 10%, sodium citrate: 2.5%, sodium gluconate 1.5%, polymeric dispersant (sodium polyacrylate) 40%: 5%, soda ash (Na2CO3): 1.5%, silicone defoamer: 0.2%, and deionized water: 60.3%.

[0037] The preparation method of commonly available anti-stain soaps includes the following steps: Add deionized water to the reactor, turn on the stirrer, and control the speed at 300 rpm. Add soda ash and continue stirring for 20 minutes. Raise the temperature to 40°C, add sodium fatty alcohol sulfate (SLES), and stir until completely transparent. Then add sodium α-alkenyl sulfonate (AOS) and stir until transparent.

[0038] Continue adding fatty alcohol polyoxyethylene ether AEO-9, stir for 15 minutes, then add sodium citrate and sodium gluconate and continue stirring for 30 minutes.

[0039] Add the polymeric dispersant (sodium polyacrylate) and stir for 5 minutes. Finally, add the silicone defoamer and stir at 100 rpm for 5 minutes. After cooling to room temperature, the target soap detergent is obtained.

[0040] Comparative Example 3 (Ternary system in which AA is replaced by MAS) Replace "AA (acrylic acid)" in the monomer with an equal amount of MAS (methacrylic acid), while keeping PVP and AMPS unchanged, to prepare an aqueous solution of the terpolymer. The remaining components and proportions of the soaping agent are the same as in Example 1.

[0041] Comparative Example 4 (GLDA-Na4 replaced with a traditional chelating agent) Replace "GLDA-Na4 (green chelating agent)" in the formulation with an equal amount of EDTA-2Na (traditional chelating agent). The remaining components are the same as in Example 1.

[0042] The application effects of the auxiliaries finally obtained in Examples 1-3 and Comparative Examples 1-4 in the actual soaping process after reactive dyeing of cotton were compared. The specific test methods are as follows: 1. Test Sample Cotton fabrics dyed with Reactive Red 3BS (weight 180 g / m²) were selected and treated with soaping agents from Examples 1-3 and Comparative Examples 1-4, respectively. The soaping process is as follows: Examples 1-3: Bath ratio 1:20, soap dosage 1.5g / L, temperature 70℃, time 20min, followed by 2 hot water washes (60℃) and 1 cold water wash, then dried; Comparative Examples 1-4: liquor ratio 1:20, soap dosage 2.0 g / L, temperature 95℃, time 30 min, followed by 3 hot water washes (80℃) and 1 cold water wash, then dried.

[0043] 2. Testing Standards and Methods (1) White ground anti-staining grade: The test shall be conducted in accordance with the "Textiles Color Fastness Test Assessment Gray Scale for Staining" (GB / T 251—2008), and the gray scale shall be used for rating.

[0044] (2) Floating color removal rate: The absorbance of the dye solution before and after soaping was measured by UV-Vis spectrophotometer, and the removal rate was calculated; Floating color removal rate (%) = (Absorbance before soaping - Absorbance after soaping) / Absorbance before soaping × 100%.

[0045] (3) Hard water resistance: Prepare a solution of 300ppm Ca 2+ For hard water, add soap and detergent according to the process dosage, observe the appearance stability (whether there is sedimentation or flocculation), and test its white surface anti-stain level.

[0046] (4) Rubbing fastness: The dry and wet rubbing fastness were determined according to GB / T 3920-2008 "Textiles - Tests for color fastness to rubbing".

[0047] (5) Relative energy consumption: Taking the total energy consumption of the soap washing process in Comparative Example 1 as the baseline (100%), calculate the relative ratio of heating energy consumption + auxiliary energy consumption (stirring, washing) of each system.

[0048] ① Heating energy consumption (E 加 (Unit: kJ) To calculate the effective energy consumption for heating the soap bath solution from room temperature (25℃, the normal temperature in the dyeing and printing workshop) to the target soap washing temperature (T), the specific heat capacity formula is used, neglecting the effect of trace amounts of soaping agent added on the heat capacity of the aqueous solution. The formula is as follows: E 加 = c×m×ΔT Specific heat capacity of water, c: fixed at 4.2 kJ / (kg·℃) (general standard value in the textile printing and dyeing industry); Total mass m of soap bath solution: calculated at a bath ratio of 1:20, bath ratio of fabric mass (bath ratio of 1:20 for all groups, no difference); Temperature difference ΔT: ΔT = target washing temperature (T) - room temperature (25℃) ②Auxiliary energy consumption (E 辅 (Unit: kJ) This includes the energy consumption of equipment agitation during the soaping process and the water supply energy consumption of the water washing process. Since there are only slight differences in the agitation speed and water washing frequency / volume among the various groups in the patent, in order to simplify the calculation and ensure the validity of the comparison, the auxiliary energy consumption is fixed at 5% of the heating energy consumption, as shown in the following formula: E 辅 =E 加 ×5% ③ Total energy consumption of the entire soap washing process (E 总 (Unit: kJ) E 总 = E 加+ E 辅 = E 加 ×1.05 ④ Relative energy consumption (R, unit: %) Since auxiliary energy consumption is a fixed proportion of heating energy consumption, the relative value of energy consumption can be directly simplified to the ratio of heating energy consumption (the ratio of total energy consumption is exactly the same as the ratio of heating energy consumption). The simplified formula is as follows:

[0049] (6) Salt and alkali resistance: Prepare a high-salt, high-alkali solution (containing 5 g / L sodium sulfate + 2 g / L soda ash, pH=10±0.5) simulating the soaping process after reactive dyeing. Add the soaping agent at the process dosage of 1.5 g / L, place in a 70℃ constant temperature water bath and stir for 20 min. Observe the appearance stability of the soaping agent system (whether it separates into layers, flocculates, or precipitates), and test the anti-staining grade of the white ground under this system according to (GB / T 251-2008). Evaluate the overall performance based on appearance stability and anti-staining grade. The evaluation criteria are as follows: Advantages: No stratification, no flocculation, no sedimentation; anti-sticking rating ≥ 4. Good: Slight stratification, no flocculation or sedimentation, anti-sticking level 3-4. Poor: Severe stratification / flocculation / precipitation, anti-fouling level ≤ 3 The test results of the soap detergents in Examples 1-3 and Comparative Examples 1-4 are shown in Table 1: Table 1. Performance test results of soap detergents in Examples 1-3 and Comparative Examples 1-4

[0050] As shown in Table 1, the soaping agents of Examples 1-3 of this invention achieve a white surface anti-staining level of 4-5 and a floating color removal rate of ≥93.1% under a temperature of 70℃, which is significantly better than the comparative examples. Moreover, there is no precipitation in a 300ppm hard water environment, and the anti-staining effect is stable in a high saline and alkaline residual environment, while the comparative examples all show slight precipitation or even flocculation, and the anti-staining performance is reduced. They are phosphorus-free and APEO-free, with excellent environmental performance. The energy consumption is reduced by more than 28% compared with the traditional process, which meets the energy-saving requirements.

[0051] A comparison of Example 1 and Comparative Example 1 shows that the performance of the PAA-PVP-AMPS terpolymer significantly surpasses that of the PAA-PVP binary copolymer. Comparing Example 1 and Comparative Example 2, while commercially available soaps can meet general customer needs under low hard water and high temperature conditions, their anti-staining ability is inferior to Example 1. Furthermore, Comparative Example 2 exhibits system instability under poor water quality, significantly impacting performance. Its high energy consumption during use is detrimental to energy conservation and emission reduction. Comparing Example 1 and Comparative Example 3, Example 1 uses acrylic acid (AA) as the polymer monomer, while Comparative Example 3 replaces AA with methacrylic acid (MAS). Example 1 demonstrates superior performance in white ground anti-staining, floating color removal, salt and alkali resistance / hard water resistance, and color fastness. The core reason is the difference in molecular structure between AA and MAS, which directly disrupts the chelating, dispersing, and weather-resistant core functions of the terpolymer. Comparative Example 3 exhibits system instability under high hard water and high salt and alkali conditions, resulting in decreased anti-staining effect. Compared with Comparative Example 4, Example 1 shows that GLDA-Na4 is the optimal chelating agent for the soaping agent system of the present invention. It has strong chelation, resistance to salt and alkali, resistance to hard water, green biodegradability, and high synergy. In contrast, traditional chelating agents have poor adaptability to working conditions, fail to meet environmental protection standards, and have weak synergy, resulting in a decline in the overall performance of the soaping agent.

[0052] In addition to the above embodiments, the present invention also includes other embodiments. All technical solutions formed by equivalent transformation or equivalent substitution should fall within the protection scope of the claims of the present invention.

Claims

1. A PAA-PVP-AMPS terpolymer-based anti-stain soaping agent for cotton, characterized in that: By weight percentage, it includes the following components: 25-35% aqueous solution of PAA-PVP-AMPS terpolymer Bio-based nonionic surfactants 5-12% Green chelating agent 4-8% Low-foaming penetrant 2-5% Deionized water 40-64% The solid content of the PAA-PVP-AMPS terpolymer aqueous solution is 30-40%; The PAA-PVP-AMPS terpolymer is polymerized from the following monomers in parts by weight: 25-40 parts of acrylic acid (AA), 10-20 parts of polyvinylpyrrolidone (PVP), and 8-15 parts of 2-acrylamide-2-methylpropanesulfonic acid (AMPS).

2. The PAA-PVP-AMPS terpolymer-based anti-stain soaping agent for cotton according to claim 1, characterized in that: The PAA-PVP-AMPS terpolymer was prepared by the following method: (1) Add deionized water to the reactor, heat to 75-85℃, and purge with nitrogen for protection; (2) Add AA monomer, PVP and initiator in sequence, and stir at constant temperature for 1.5-2h; then add a mixture of AMPS monomer and chain transfer agent dropwise, with the dropwise addition time controlled at 1-1.5h, and keep the reaction at the temperature for 2-3h after the dropwise addition is completed; cool down to below 40℃, and adjust the pH to 6.0-7.0 with sodium hydroxide solution to obtain an aqueous solution of PAA-PVP-AMPS terpolymer with a solid content of 30-40%.

3. The PAA-PVP-AMPS terpolymer-based anti-stain soaping agent for cotton according to claim 2, characterized in that: The initiator is ammonium persulfate, and its addition amount is 0.8-1.2% of the total monomer weight; the chain transfer agent is mercaptoacetic acid, and its addition amount is 0.3-0.5% of the total monomer weight.

4. The PAA-PVP-AMPS terpolymer-based anti-stain soaping agent for cotton according to claim 1, characterized in that: The bio-based nonionic surfactant is one or more of C8-C14 cocoyl alkyl glycoside, C8-C10 alkyl glycoside, and C12-C14 lauryl glycoside.

5. The PAA-PVP-AMPS terpolymer-based anti-stain soaping agent for cotton according to claim 4, characterized in that: The bio-based nonionic surfactant is a compound of C8-C14 cocoyl alkyl glycoside and C8-C10 alkyl glycoside in a weight ratio of 6-8:2-3.

6. The PAA-PVP-AMPS terpolymer-based anti-stain soaping agent for cotton according to claim 1, characterized in that: The green chelating agent is tetrasodium glutamate diacetate (GLDA-Na4).

7. The PAA-PVP-AMPS terpolymer-based anti-stain soaping agent for cotton according to claim 1, characterized in that: The low-foaming penetrant is isomeric tridecyl alcohol polyoxyethylene ether, and the number of ethylene oxide EO additions in its structure is 7-9.

8. A method for preparing a PAA-PVP-AMPS terpolymer-based anti-stain soaping agent for cotton according to any one of claims 1-7, characterized in that: Includes the following steps: (1) At room temperature, add deionized water into a clean reaction vessel, turn on the stirrer, and add green chelating agent and bio-based nonionic surfactant in sequence, stirring until completely dissolved; (2) Add low-foaming penetrant and continue stirring; (3) Slowly add the PAA-PVP-AMPS terpolymer aqueous solution, stir until the system is uniform and transparent, and let it stand to defoam.

9. The method for preparing the PAA-PVP-AMPS terpolymer-based anti-stain soaping agent for cotton according to claim 8, characterized in that: Specifically, the steps include the following: (1) At room temperature, add deionized water into a clean reaction vessel, turn on the stirrer, add green chelating agent and bio-based nonionic surfactant in sequence, and stir for 10-15 minutes until completely dissolved; (2) Add low-foaming penetrant and continue stirring for 5-10 minutes; (3) Slowly add the PAA-PVP-AMPS terpolymer aqueous solution, control the stirring speed to 200-300r / min, stir for 30-40min until the system is uniform and transparent, and let it stand to defoam.

10. The application of a PAA-PVP-AMPS terpolymer-based anti-stain soaping agent for cotton according to any one of claims 1-7, characterized in that: The cotton active anti-stain soaping agent is used to soap and wash pure cotton reactive dyed fabrics. The soaping process conditions are: liquor ratio 1:15-25, soaping agent dosage 1.0-2.0g / L, temperature 60-80℃, time 15-25min, followed by 2 hot water washes and 1 cold water wash before drying.

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