Fluoride-free waterproof agent and preparation method thereof

Abstract

The invention discloses a fluoride-free waterproof agent and a preparation method thereof.The preparation method comprises the following preparation steps that S1, an acrylate monomer, an initiator and a chain transfer agent react in a first solvent, and a first product is prepared; s2, carrying out a reaction on an organic silicon monomer, high-hydrogen-content silicone oil, tetramethyldisiloxane and an acid catalyst to prepare a second product; s3, the first product, the second product, an active monomer, isopropanol and a catalyst are subjected to a reaction, and a third product is prepared; s4, mixing the third product, a second solvent, an emulsifier and water, heating and emulsifying to obtain the fluoride-free waterproof agent. The fluoride-free waterproof agent disclosed by the invention has a relatively good waterproof effect and can improve the hand feeling of fabrics.

Description

Technical Field

[0001] The present application relates to the field of waterproofing agents, and in particular to a fluorine-free waterproofing agent and a preparation method thereof. Background Art

[0002] Fabric waterproofing agents are widely used in many fields such as clothing, outdoor products, and home textiles. In terms of clothing, it can keep jackets and raincoats dry even in heavy rain, prevent rainwater from penetrating, and ensure the comfort of the wearer; outdoor tents and backpacks can resist the invasion of bad weather after being treated with it, extend their service life, and ensure the smooth progress of outdoor activities; curtains and sofa covers in the home field can easily deal with water stains and stains after using waterproofing agents, and are easy to clean and maintain. Its importance lies in effectively improving the functionality and practicality of fabrics, meeting people's needs for fabric waterproofing in different scenarios, bringing great convenience to people's lives and work, and at the same time expanding the application range of fabrics and promoting the development of the textile industry.

[0003] At present, fluorine-containing waterproofing agents still dominate the market, but the per- and poly-fluoroalkyl substances (PFAS) they contain can cause harm to the environment and life. Octafluorocarbon waterproofing agents are currently banned in Europe and the United States, and restrictions on the use of hexafluorocarbon waterproofing agents have also been gradually tightened. Therefore, research and development of green and environmentally friendly fluorine-free waterproofing agents has become a hot topic in the market.

[0004] Conventional polyacrylate-based fluorine-free waterproofing agents are very popular in the market due to their excellent cost-effectiveness, but this type of fluorine-free waterproofing agent has problems such as poor feel. The conventional solution is to compound polyacrylate-based fluorine-free with special silicone emulsions, but this brings about problems such as difficulty in balancing waterproof performance and feel, and poor processing stability of the compounded emulsion. Summary of the invention

[0005] The purpose of the present application is to provide a fluorine-free waterproof agent, which can provide good hand feel and processing stability for fabrics after being treated.

[0006] To achieve the above objectives, the technical solution adopted in the present application is: to provide a method for preparing a fluorine-free waterproofing agent, comprising the following preparation steps: S1: reacting an acrylate monomer, an initiator and a chain transfer agent in a first solvent to obtain a first product; S2: reacting an organosilicon monomer, a high hydrogen silicone oil, tetramethyldisiloxane and an acid catalyst to obtain a second product; S3: reacting the first product, the second product, an active monomer, isopropanol and a catalyst to obtain a third product; S4: mixing the third product, a second solvent, an emulsifier and water, heating and emulsifying to obtain the fluorine-free waterproofing agent.

[0007] Preferably, the first product is an acrylate prepolymer containing active groups, the second product is a hydrogen-containing silicone oil containing side chain hydrogen or terminal hydrogen, and the third product is an acrylate-modified silicone prepolymer.

[0008] As another preference, the acrylate monomer is any one of methyl acrylate, octyl acrylate, dodecyl acrylate, tetradecyl acrylate, hexadecyl acrylate, octadecyl acrylate, behenyl acrylate, methyl methacrylate, octyl methacrylate, dodecyl methacrylate, tetradecyl methacrylate, hexadecyl methacrylate, octadecyl methacrylate, behenyl methacrylate, isodecyl acrylate, and isooctyl acrylate, or a combination of more thereof.

[0009] As another preference, the high hydrogen silicone oil has a hydrogen content of 1.5%.

[0010] As another preference, the active monomer is any one of hydroxyethyl acrylate, hydroxyethyl methacrylate, glycidyl acrylate, and glycidyl methacrylate, or a combination of more than one thereof.

[0011] As another preference, the emulsifier is a mixture of a nonionic emulsifier and a cationic emulsifier in a mass ratio of (19:2) to (1:4).

[0012] As another preference, the chain transfer agent is any one of 2-[dodecylthio(thiocarbonyl)thio]-2-methylpropionic acid, 4-cyano-4-(dithiobenzoyloxy)pentanoic acid, and 4-cyanopentanoic acid-4-ethyl trithiocarbonate, or a combination of more than one thereof.

[0013] As another preferred embodiment, the initiator is any one or a combination of azobiscyanovaleric acid, azobisisopropylimidazoline, tert-butyl perbenzoate or dilauric acid peroxide, and azobisisobutyronitrile; the first solvent is any one or a combination of ethylene glycol butyl ether, diethylene glycol butyl ether, anhydrous ethanol, acetone, isopropanol, dipropylene glycol dimethyl ether, N,N'-dimethylformamide, and dimethyl sulfoxide; the second solvent is any one or a combination of ethylene glycol, propylene glycol, dipropylene glycol, tripropylene glycol, dipropylene glycol dimethyl ether, dipropylene glycol ethyl ether, tripropylene glycol ethyl ether, ethylene glycol butyl ether, diethylene glycol butyl ether, triethylene glycol butyl ether, ethanol, ethyl ether, isopropanol, and 3-methoxy-3-methyl-1-butanol.

[0014] Further preferably, in parts by mass, the preparation steps are specifically as follows: S1: 50 to 85 parts of the acrylate monomer, 0.3 to 2 parts of the initiator, 0.05 to 1.5 parts of the chain transfer agent and 25 to 45 parts of the first solvent are mixed, and reacted at 60 to 90° C. for 2 to 5 hours to prepare the first product; S2: 85 to 95 parts of the organosilicon monomer, 3 to 10 parts of the high hydrogen silicone oil, 0.5 to 5 parts of the tetramethyldisiloxane and 0.5 to 5 parts of the acid catalyst are mixed, reacted at 30 to 50° C. for a period of time, heated to 40 to 80° C. and added with a base, Neutralize for a period of time, then filter and remove impurities to obtain the second product; S3: mix 50-85 parts of the first product, 25-45 parts of the second product, 5-15 parts of the active monomer, and 10-20 parts of the isopropanol, heat to 55-60°C, add 0.1-3 parts of the catalyst, gradually heat to 80-90°C and react for a period of time to obtain the third product; S4: mix 30-45 parts of the third product, 5-20 parts of the second solvent, 3-15 parts of the emulsifier and 45-65 parts of the water, heat to 55-60°C and emulsify to obtain the fluorine-free waterproofing agent.

[0015] The present application also provides a fluorine-free waterproofing agent, which is prepared by any of the above-mentioned preparation methods.

[0016] Compared with the prior art, the beneficial effects of this application are:

[0017] (1) The waterproofing agent of the present application does not contain fluorine, is safer for the human body and the environment, does not cause irritation or allergic reactions to the human body, and can provide people with a safer and healthier use experience;

[0018] (2) The fluorine-free waterproofing agent of the present application has a good waterproof effect and can improve the feel of the fabric;

[0019] (3) The fluorine-free waterproofing agent of the present application has good processing performance, and its salt resistance and alkali resistance are excellent, which is conducive to expanding the applicable scenarios of the fluorine-free waterproofing agent. DETAILED DESCRIPTION

[0020] Below, the present application is further described in conjunction with specific implementation methods. It should be noted that, under the premise of no conflict, the various embodiments or technical features described below can be arbitrarily combined to form new embodiments.

[0021] The terms "including" and "having" and any variations thereof in the specification and claims of this application are intended to cover non-exclusive inclusions. For example, a process, method, system, product or apparatus comprising a series of steps or units is not necessarily limited to those steps or units explicitly listed, but may include other steps or units not explicitly listed or inherent to these processes, methods, products or apparatuses.

[0022] The present application provides a method for preparing a fluorine-free waterproofing agent, comprising the following preparation steps:

[0023] S1: preparing a first product by reacting an acrylate monomer, an initiator, a chain transfer agent and a first solvent;

[0024] S2: preparing a second product by reacting an organic silicon monomer, a high hydrogen silicone oil, tetramethyldisiloxane and an acid catalyst;

[0025] S3: reacting the first product, the second product, the active monomer, isopropanol and the catalyst to obtain a third product;

[0026] S4: Mix the third product, the second solvent, the emulsifier and water, increase the temperature and emulsify, to obtain the fluorine-free waterproofing agent of the present application.

[0027] Among them, the first product is an acrylate prepolymer containing active groups, the second product is a hydrogen-containing silicone oil containing side chain hydrogen or terminal hydrogen, and the third product is an acrylate-modified silicone polymer.

[0028] The fluorine-free waterproofing agent of the present application is prepared by reversible addition-fragmentation chain transfer polymerization (RAFT) to obtain an acrylate prepolymer with an active group, and further reacts with hydrogen-containing silicone oil. The prepared fluorine-free waterproofing agent not only has a good waterproof effect, but also can effectively improve the feel of the fabric and enhance the salt and alkali resistance.

[0029] In addition, the acrylic prepolymer containing active groups is linked to the hydrogenated silicone oil through a strong chemical bond. This tight combination enables the two to form a stable structure at the molecular level, thereby effectively avoiding many problems caused by competitive adsorption between different components during actual application.

[0030] For example, in traditional waterproof finishing, different components in the waterproofing agent may compete for adsorption sites on the fabric surface, resulting in excessive silicone oil adsorption in some areas, forming silicone oil spots, affecting the appearance and feel of the fabric; while other areas may not be adsorbed enough by the waterproofing ingredients, resulting in uneven waterproofing effects, making some areas of the fabric effectively waterproof, while other areas are easily wetted by water. However, when the waterproof functional group is linked to the silicone oil component through chemical bonds, its spatial topological structure can effectively form a synergistic and anchoring effect, giving the fabric excellent waterproof effect and improving the processing stability of the waterproofing agent emulsion, while maintaining the softness and breathability of the fabric, thereby greatly improving the effect and quality of the fabric waterproof finishing, providing people with more reliable and comfortable waterproof fabric products.

[0031] In some embodiments, the acrylate monomer is any one of methyl acrylate, octyl acrylate, dodecyl acrylate, tetradecyl acrylate, hexadecyl acrylate, octadecyl acrylate, behenyl acrylate, methyl methacrylate, octyl methacrylate, dodecyl methacrylate, tetradecyl methacrylate, hexadecyl methacrylate, octadecyl methacrylate, behenyl methacrylate, isodecyl acrylate, and isooctyl acrylate, or a combination of more thereof.

[0032] In some embodiments, the initiator is any one of azobiscyanovaleric acid, azobisisopropylimidazoline, tert-butyl perbenzoate or dilauric acid peroxide, or azobisisobutyronitrile, or a combination of more than one thereof.

[0033] In some embodiments, the chain transfer agent is any one of 2-[dodecylthio(thiocarbonyl)thio]-2-methylpropionic acid, 4-cyano-4-(dithiobenzoyloxy)pentanoic acid, and 4-ethyl 4-cyanopentanoate trithiocarbonate, or a combination of more thereof.

[0034] In some embodiments, the first solvent is any one of ethylene glycol butyl ether, diethylene glycol butyl ether, anhydrous ethanol, acetone, isopropanol, dipropylene glycol dimethyl ether, N,N'-dimethylformamide, and dimethyl sulfoxide, or a combination of more than one thereof.

[0035] In some embodiments, the hydrogen content of the high hydrogen-containing silicone oil is 1.5%, which is beneficial for effectively regulating the hydrogen content of the hydrogen-containing silicone oil on the one hand, and is beneficial for the effective reaction of the active group acrylate prepolymer (first product S1) with the hydrogen-containing silicone oil (S2) on the other hand.

[0036] In some embodiments, the reactive monomer is any one of hydroxyethyl acrylate, hydroxyethyl methacrylate, glycidyl acrylate, and glycidyl methacrylate, or a combination of more than one thereof.

[0037] In some embodiments, the second solvent is any one of ethylene glycol, propylene glycol, dipropylene glycol, tripropylene glycol, dipropylene glycol dimethyl ether, dipropylene glycol ethyl ether, tripropylene glycol ethyl ether, ethylene glycol butyl ether, diethylene glycol butyl ether, triethylene glycol butyl ether, ethanol, ethyl ether, isopropanol, and 3-methoxy-3-methyl-1-butanol, or a combination of more than one thereof.

[0038] In some embodiments, the emulsifier can be a nonionic emulsifier and a cationic emulsifier. In a preferred embodiment, the emulsifier is a mixture of a nonionic emulsifier and a cationic emulsifier.

[0039] The nonionic emulsifier may be any one or a combination of ethers, esters, ester ethers, alkanolamides, polyols and amine oxides; the cationic emulsifier may be any one or a combination of amines, amine salts, quaternary ammonium salts, imidazolines and imidazolinium salts.

[0040] In some embodiments, the mass ratio of the nonionic emulsifier to the cationic emulsifier is (19:2) to (1:4).

[0041] In some embodiments, the amount of emulsifier added is 5% to 20% of the mass of the third product.

[0042] In some embodiments, the specific preparation steps are as follows, based on parts by mass:

[0043] S1: 50 to 85 parts of an acrylate monomer, 0.3 to 2 parts of an initiator, 0.05 to 1.5 parts of a chain transfer agent, and 25 to 45 parts of a first solvent are mixed, and reacted at 60 to 90° C. for 2 to 5 hours to prepare a first product;

[0044] S2: 85-95 parts of organosilicon monomer, 3-10 parts of high hydrogen silicone oil, 0.5-5 parts of tetramethyldisiloxane and 0.5-5 parts of acid catalyst are mixed, reacted at 30-50°C for a period of time, heated to 40-80°C and alkali is added, neutralized for a period of time, filtered and impurities are removed, and the second product is obtained;

[0045] S3: 50-85 parts of the first product, 25-45 parts of the second product, 5-15 parts of the active monomer, and 10-20 parts of isopropanol are mixed, the temperature is raised to 55-60° C., 0.1-3 parts of the catalyst are added, the temperature is gradually raised to 80-90° C., and the mixture is reacted for a period of time to obtain a third product;

[0046] S4: 30 to 45 parts of the third product, 5 to 20 parts of the second solvent, 3 to 15 parts of the emulsifier and 45 to 65 parts of water are mixed, the temperature is raised to 55 to 60° C. and emulsified to obtain the fluorine-free waterproofing agent of the present application.

[0047] The preparation method of the fluorine-free waterproof agent of the present application is simple. The prepared waterproof agent can give the treated fabric a better feel and alkali and salt resistance stability while ensuring the waterproof effect, and has practical application significance.

[0048] Example 1

[0049] Prepare a fluorine-free waterproofing agent according to the following preparation steps:

[0050] S1: 400 g of behenyl acrylate, 250 g of octadecyl acrylate, 50 g of octyl acrylate, 1.5 g of 2-[dodecylthio(thiocarbonyl)thio]-2-methylpropionic acid, 200 g of anhydrous ethanol, 95.5 g of ethylene glycol butyl ether and 3 g of azobisisobutyronitrile were sequentially added into a four-necked flask, and reacted at 75° C. for 3.5 hours to obtain a first product;

[0051] S2: 1000g of organosilicon monomer (DMC), 50g of high hydrogen silicone oil and 14g of tetramethyldisiloxane were put into a four-necked flask with condensation reflux, 11g of 98wt% concentrated sulfuric acid was added, the temperature was first raised to 40°C and kept warm for 10h, then the temperature was raised to 50°C, 25g of sodium bicarbonate was added and stirred for neutralization, and after 5 hours, the mixture was filtered and impurities were removed to obtain the second product;

[0052] S3: 550 g of the first product, 260 g of the second product, 60 g of hydroxyethyl acrylate and 128 g of isopropanol were added to a four-necked flask, the temperature was raised to 55-60° C., 2 g of Custer catalyst was added and the temperature was gradually raised to 80-90° C., and the third product was obtained after reacting for 6 hours;

[0053] S4: 350g of the third product, 100g of dipropylene glycol, 15g of sorbitan laurate, 20g of hexadecyltrimethylammonium chloride and 515g of water are added into a four-necked flask, the temperature is raised to 55-60°C, and after high-speed dispersion for 1 hour, homogenization and emulsification are performed to obtain a fluorine-free waterproofing agent of the present application after emulsification.

[0054] Example 2

[0055] Prepare a fluorine-free waterproofing agent according to the following preparation steps:

[0056] S1: 400 g of behenyl acrylate, 250 g of octadecyl acrylate, 50 g of isooctyl acrylate, 0.8 g of 2-[dodecylthio(thiocarbonyl)thio]-2-methylpropionic acid, 200 g of anhydrous ethanol, 96.2 g of ethylene glycol butyl ether and 3 g of azobisisobutyronitrile were sequentially added into a four-necked flask, and reacted at 75° C. for 3.5 hours to obtain a first product;

[0057] S2: 1000g of organosilicon monomer (DMC), 45g of high hydrogen silicone oil and 19g of tetramethyldisiloxane were put into a four-necked flask with condensation reflux, 11g of 98wt% concentrated sulfuric acid was added, the temperature was first raised to 40°C and kept warm for 10h, then the temperature was raised to 50°C, 25g of sodium bicarbonate was added and stirred for neutralization, and after 5 hours, the mixture was filtered and impurities were removed to obtain the second product;

[0058] S3: 600 g of the first product, 255 g of the second product, 60 g of glycidyl acrylate and 83 g of isopropanol were added to a four-necked flask, the temperature was raised to 55-60° C., 2 g of Custer catalyst was added and the temperature was gradually raised to 80-90° C., and the third product was obtained after reacting for 6 hours;

[0059] S4: 350g of the third product, 80g of dipropylene glycol, 20g of diethylene glycol butyl ether, 15g of anhydrous sorbitan laurate, 20g of hexadecyltrimethylammonium chloride and 515g of water are added into a four-necked flask, the temperature is raised to 55-60°C, and after high-speed dispersion for 1 hour, homogenization and emulsification are performed to obtain a fluorine-free waterproofing agent of the present application after emulsification.

[0060] Example 3

[0061] Prepare a fluorine-free waterproofing agent according to the following preparation steps:

[0062] S1: 400 g of behenyl acrylate, 250 g of octadecyl methacrylate, 50 g of methyl methacrylate, 0.8 g of 2-[dodecylthio(thiocarbonyl)thio]-2-methylpropionic acid, 200 g of anhydrous ethanol, 96.2 g of ethylene glycol butyl ether and 3 g of azobisisobutyronitrile were sequentially added into a four-necked flask, and reacted at 75° C. for 3.5 hours to obtain a first product;

[0063] S2: 950 g of organosilicon monomer (DMC), 80 g of high hydrogen silicone oil and 34 g of tetramethyldisiloxane were put into a four-necked flask with condensation reflux, 11 g of 98 wt% concentrated sulfuric acid was added, the temperature was first raised to 40°C and kept warm for 10 hours, then the temperature was raised to 50°C, 25 g of sodium bicarbonate was added and stirred for neutralization, and after 5 hours, the mixture was filtered and impurities were removed to obtain the second product;

[0064] S3: 600 g of the first product, 255 g of the second product, 60 g of glycidyl acrylate and 83 g of isopropanol were added to a four-necked flask, the temperature was raised to 55-60° C., 2 g of Custer catalyst was added and the temperature was gradually raised to 80-90° C., and the third product was obtained after reacting for 6 hours;

[0065] S4: 350g of the third product, 80g of dipropylene glycol, 20g of diethylene glycol butyl ether, 15g of anhydrous sorbitan laurate, 20g of hexadecyltrimethylammonium chloride and 515g of water are added into a four-necked flask, the temperature is raised to 55-60°C, and after high-speed dispersion for 1 hour, homogenization and emulsification are performed to obtain a fluorine-free waterproofing agent of the present application after emulsification.

[0066] Example 4

[0067] Prepare a fluorine-free waterproofing agent according to the following preparation steps:

[0068] S1: 400 g of behenyl acrylate, 250 g of octadecyl methacrylate, 50 g of methyl methacrylate, 0.8 g of 2-[dodecylthio(thiocarbonyl)thio]-2-methylpropionic acid, 200 g of anhydrous ethanol, 96.2 g of ethylene glycol butyl ether and 3 g of azobisisobutyronitrile were sequentially added into a four-necked flask, and reacted at 75° C. for 3.5 hours to obtain a first product;

[0069] S2: 950 g of organosilicon monomer (DMC), 80 g of high hydrogen silicone oil and 34 g of tetramethyldisiloxane were put into a four-necked flask with condensation reflux, 11 g of 98 wt% concentrated sulfuric acid was added, the temperature was first raised to 40°C and kept warm for 10 hours, then the temperature was raised to 50°C, 25 g of sodium bicarbonate was added and stirred for neutralization, and after 5 hours, the mixture was filtered and impurities were removed to obtain the second product;

[0070] S3: 580 g of the first product, 275 g of the second product, 40 g of glycidyl acrylate, 20 g of hydroxyethyl acrylate and 83 g of isopropanol were added to a four-necked flask, the temperature was raised to 55-60° C., 2 g of Custer catalyst was added and the temperature was gradually raised to 80-90° C., and the third product was obtained after reacting for 6 hours;

[0071] S4: 350g of the third product, 80g of tripropylene glycol, 20g of diethylene glycol butyl ether, 15g of anhydrous sorbitan laurate, 20g of hexadecyltrimethylammonium chloride and 515g of water are added into a four-necked flask, the temperature is raised to 55-60°C, and after high-speed dispersion for 1 hour, homogenization and emulsification are performed to obtain a fluorine-free waterproofing agent of the present application after emulsification.

[0072] Example 5

[0073] Prepare a fluorine-free waterproofing agent according to the following preparation steps:

[0074] S1: 400 g of hexadecyl acrylate, 250 g of tetradecyl acrylate, 50 g of isooctyl acrylate, 0.8 g of 4-cyano-4-(dithiobenzoyloxy)pentanoic acid, 200 g of ethylene glycol butyl ether, 96.2 g of isopropanol and 3 g of azobisisobutyronitrile were sequentially added into a four-necked flask, and reacted at 75° C. for 3.5 hours to obtain a first product;

[0075] S2: 950 g of organosilicon monomer (DMC), 80 g of high hydrogen silicone oil and 34 g of tetramethyldisiloxane were put into a four-necked flask with condensation reflux, 11 g of 98 wt% concentrated sulfuric acid was added, the temperature was first raised to 40°C and kept warm for 10 hours, then the temperature was raised to 50°C, 25 g of sodium bicarbonate was added and stirred for neutralization, and after 5 hours, the mixture was filtered and impurities were removed to obtain the second product;

[0076] S3: 580 g of the first product, 275 g of the second product, 60 g of hydroxyethyl acrylate and 83 g of isopropanol were added to a four-necked flask, the temperature was raised to 55-60° C., 2 g of Custer catalyst was added and the temperature was gradually raised to 80-90° C., and the third product was obtained after reacting for 6 hours;

[0077] S4: 350g of the third product, 80g of tripropylene glycol, 20g of diethylene glycol butyl ether, 15g of anhydrous sorbitan laurate, 20g of hexadecyltrimethylammonium chloride and 515g of water are added into a four-necked flask, the temperature is raised to 55-60°C, and after high-speed dispersion for 1 hour, homogenization and emulsification are performed to obtain a fluorine-free waterproofing agent of the present application after emulsification.

[0078] Comparative Example 1

[0079] A comparative waterproofing agent was prepared. During the preparation of the first product in step S1, 2-[dodecylthio(thiocarbonyl)thio]-2-methylpropionic acid was not added, and the other preparation steps were consistent with the preparation steps in Example 1.

[0080] Comparative Example 2

[0081] A conventional fabric waterproofing agent is prepared by mixing a commercially available polyacrylic acid-based fluorine-free waterproofing agent with a special softener for waterproofing in one bath at a mass ratio of 8:2.

[0082] Comparative Example 3

[0083] A conventional fabric waterproofing agent is prepared by mixing a commercially available polyacrylic acid-based fluorine-free waterproofing agent with a special softener for waterproofing in one bath at a mass ratio of 7:3.

[0084] Performance Testing

[0085] 1. Waterproof effect test: According to the national standard GB 4575-2012 test method: Take at least three samples from different positions of the finished fabric, each sample size is at least 18cm×18cm, and the sample should be representative, and there should be no wrinkles or creases at the sampling position. Place the sample face up, tighten it on a metal ring of 150±2mm to form a smooth surface, and then tilt it 45°. Set a nozzle 150mm above it to quickly spray 250ml of water on the inclined sample surface within 25-30s. After the spraying is completed, quickly remove the clamp, make the fabric face down, and then gently tap it against a hard object twice, observe the wetting of the sample, and then judge the waterproof level according to the standard, and take the average value of multiple samples. The rating standard for waterproof effect is shown in Table 1.

[0086] Table 1 Waterproof effect evaluation standard

[0087] 2. Hand feel evaluation: Evaluate by touch with your hands, using a 1-5 point scoring method, with 1 point being the worst and 5 points being the best. 5 people evaluate at the same time and take the average value.

[0088] The fabric waterproofing agents prepared in the embodiments and comparative examples were applied to chemical fiber woven fabrics and cotton woven fabrics, respectively, and the test results of the waterproofing effect and hand feel performance were recorded in the following Table 2.

[0089] Table 2 Waterproof performance and hand feel evaluation test of various fabrics

[0090] Analyzing the performance test results in Table 2, the chemical fiber woven fabric or cotton woven fabric treated with the fluorine-free waterproof agent of the present application can obtain a relatively significant improvement in the waterproof effect, and has no effect on the feel of various fabrics.

[0091] 3. Salt resistance and stability: Use 5g / L salt solution (Na2SO4 15g / L+Na2CO3) to prepare 30g / L waterproofing agent working solution, and observe whether the working solution has floating oil, stratification and unstable precipitation at room temperature, 50℃, 60℃ and 70℃ respectively.

[0092] 4. Alkali resistance and stability: Use 1.2g / L caustic soda solution (NaOH) to prepare 30g / L waterproofing agent working solution, and observe whether the working solution has floating oil, stratification and unstable precipitation at room temperature, 50℃, 60℃ and 70℃ respectively.

[0093] The salt resistance stability and alkali resistance stability test results of each embodiment and each comparative example are recorded in the following Table 3.

[0094] Table 3 Test results of salt resistance stability and alkali resistance stability of waterproofing agents in various embodiments and comparative examples

[0095] From the performance test results in Table 3, it can be seen that the fluorine-free waterproofing agent prepared in each embodiment of the present application has good salt resistance stability and alkali resistance stability. It can maintain stability in a salt solution at 60°C and an alkaline solution at 50°C, while the conventional waterproofing agent even exhibits oil floating when mixed with a salt solution and an alkaline solution at room temperature. From the performance test results in Table 3, it can be seen that the fluorine-free waterproofing agent of the present application has better stability, is suitable for application in more usage scenarios, and is more stable and less prone to deterioration during transportation.

[0096] In summary, the fluorine-free waterproofing agent of the present application has good waterproof performance, good hand feel, and excellent processing stability, and has practical practicability.

[0097] The above describes the basic principles, main features and advantages of the present application. Those skilled in the art should understand that the present application is not limited by the above embodiments, and the above embodiments and the specification only describe the principles of the present application. The present application may have various changes and improvements without departing from the spirit and scope of the present application, and these changes and improvements fall within the scope of the present application for which protection is sought. The scope of protection claimed by the present application is defined by the attached claims and their equivalents.

Claims

1. A method for preparing a fluorine-free waterproofing agent, characterized in that: The method comprises the following preparation steps: S1: reacting an acrylate monomer, an initiator and a chain transfer agent in a first solvent to prepare a first product; S2: preparing a second product by reacting an organic silicon monomer, a high hydrogen silicone oil, tetramethyldisiloxane and an acid catalyst; S3: reacting the first product, the second product, an active monomer, isopropanol and a catalyst to obtain a third product; S4: mixing the third product, the second solvent, the emulsifier and water, heating and emulsifying, to obtain the fluorine-free waterproofing agent.

2. The preparation method according to claim 1, characterized in that The first product is an acrylate prepolymer containing active groups, the second product is a hydrogen-containing silicone oil containing side chain hydrogen or terminal hydrogen, and the third product is an acrylate-modified organosilicon prepolymer.

3. The preparation method according to claim 1, characterized in that: The acrylic acid ester monomer is any one of methyl acrylate, octyl acrylate, dodecyl acrylate, tetradecyl acrylate, hexadecyl acrylate, octadecyl acrylate, behenyl acrylate, methyl methacrylate, octyl methacrylate, dodecyl methacrylate, tetradecyl methacrylate, hexadecyl methacrylate, octadecyl methacrylate, behenyl methacrylate, isodecyl acrylate, and isooctyl acrylate, or a combination of more than one thereof.

4. The preparation method according to claim 1, characterized in that: The hydrogen content of the high hydrogen silicone oil is 1.5%.

5. The preparation method according to claim 1, characterized in that: The active monomer is any one of hydroxyethyl acrylate, hydroxyethyl methacrylate, glycidyl acrylate, and glycidyl methacrylate, or a combination of multiple thereof.

6. The preparation method according to claim 1, characterized in that: The emulsifier is a mixture of a nonionic emulsifier and a cationic emulsifier in a mass ratio of (19:2) to (1:4).

7. The preparation method according to claim 1, characterized in that: The chain transfer agent is any one of 2-[dodecylthio(thiocarbonyl)thio]-2-methylpropionic acid, 4-cyano-4-(dithiobenzoyloxy)pentanoic acid, and 4-cyanopentanoic acid-4-ethyl trithiocarbonate or a combination of more than one thereof.

8. The preparation method according to claim 1, characterized in that: The initiator is any one or a combination of azobiscyanovaleric acid, azobisisopropylimidazoline, tert-butyl perbenzoate or dilauric acid peroxide, and azobisisobutyronitrile; the first solvent is any one or a combination of ethylene glycol butyl ether, diethylene glycol butyl ether, anhydrous ethanol, acetone, isopropanol, dipropylene glycol dimethyl ether, N,N'-dimethylformamide, and dimethyl sulfoxide; the second solvent is any one or a combination of ethylene glycol, propylene glycol, dipropylene glycol, tripropylene glycol, dipropylene glycol dimethyl ether, dipropylene glycol ethyl ether, tripropylene glycol ethyl ether, ethylene glycol butyl ether, diethylene glycol butyl ether, triethylene glycol butyl ether, ethanol, ethyl ether, isopropanol, and 3-methoxy-3-methyl-1-butanol.

9. The preparation method according to any one of claims 1 to 8, characterized in that: In terms of parts by mass, the preparation steps are specifically as follows: S1: 50 to 85 parts of the acrylic acid ester monomer, 0.3 to 2 parts of the initiator, 0.05 to 1.5 parts of the chain transfer agent and 25 to 45 parts of the first solvent are mixed, and reacted at 60 to 90° C. for 2 to 5 hours to prepare the first product; S2: 85-95 parts of the organosilicon monomer, 3-10 parts of the high hydrogen silicone oil, 0.5-5 parts of the tetramethyldisiloxane and 0.5-5 parts of the acid catalyst are mixed, reacted at 30-50° C. for a period of time, heated to 40-80° C. and added with alkali, neutralized for a period of time, filtered and impurities removed, to obtain the second product; S3: 50-85 parts of the first product, 25-45 parts of the second product, 5-15 parts of the active monomer, and 10-20 parts of the isopropanol are mixed, the temperature is raised to 55-60° C., 0.1-3 parts of the catalyst are added, the temperature is gradually raised to 80-90° C., and the mixture is reacted for a period of time to obtain the third product; S4: 30 to 45 parts of the third product, 5 to 20 parts of the second solvent, 3 to 15 parts of the emulsifier and 45 to 65 parts of the water are mixed, the temperature is raised to 55 to 60° C. and emulsified to obtain the fluorine-free waterproofing agent.

10. A fluorine-free waterproofing agent, characterized in that: The invention is prepared by the preparation method of a fluorine-free waterproofing agent according to any one of claims 1 to 9.

Images