CN109610177B - Preparation method and application of cationic polyurethane acrylate water repellent agent - Google Patents

Abstract

The invention discloses a preparation method and application of a cationic polyurethane acrylate water repellent agent, and belongs to the field of environment-friendly textiles. In the water repellent prepared by the invention, the polyurethane and the acrylate are connected by chemical bonds, and the polymer has excellent film forming property, flexibility and water repellency; the polymer self-emulsification is realized by introducing the cationizable monomer in the polymerization process, and the problems of water repellency effect reduction, environmental pollution and the like caused by emulsification of a conventional acrylate water repellent agent by an external low-molecular surfactant are avoided; meanwhile, the cationic water repellent avoids the problem that the conventional anionic product cannot be tightly adsorbed with the fabric, and is more beneficial to the uniform film formation of the water repellent on the surface of the fabric; the cationic polyurethane-acrylate water repellent agent prepared by the invention avoids the problems of environmental pollution and bioaccumulation toxicity caused by fluorine-containing water repellent agents, and has wide application prospect.

Description

A kind of preparation method and application of cationic polyurethane acrylate water repellent

technical field

The invention relates to a preparation and application method of a cationic polyurethane acrylate water repellent, and belongs to the field of textiles.

Background technique

The development of science and technology promotes the continuous development of the textile industry, consumers' demand for functional textiles is gradually increasing, and various functional textiles have received extensive attention and development. Hydrophobic fabrics are widely used due to their excellent water repellency, antifouling, self-cleaning and other properties. Fabrics have a long history of water repellency, and commonly used water repellents are mainly fluorine-containing compounds, silicones and aliphatic hydrocarbon compounds. Fluorine-containing water-repellent can impart excellent water-repellent effect to fabrics. However, fluorine-containing water-repellent has certain bioaccumulation and toxicity in the process of synthesis and use, so there is an ecological pollution problem; at the same time, its price is expensive, Lead to higher production and use costs. Silicone water repellent can give fabrics better water repellency and softness, but its disadvantage is that it increases the pilling and seam release on the surface of the fabric. Long-chain aliphatic hydrocarbon water repellents are mainly acrylate compounds, which can give fabrics better hydrophobic properties. However, it has defects such as hot sticking and cold brittleness, poor flexibility, and solvent resistance when used. Polyurethane is a polymer compound containing urethane repeating units on the main chain of the molecule. It has the advantages of low temperature resistance, good flexibility and high bonding strength, but it lacks hydrophobic properties. The complementarity of the advantages and disadvantages of polyurethane and acrylate polymers is beneficial to improve the wearing performance of polyacrylate water repellents. Since the 1980s, polyurethane has been used to modify acrylic products to obtain new water repellents with complementary advantages. Early polyurethane-modified acrylates used physical blending methods to improve the mutual solubility of the two molecules by hydrogen bonding of polyurethane and acrylate. However, due to the weak intermolecular force of hydrogen bonds, the stability of urethane acrylate water repellent is poor. In order to improve the compatibility between polyurethane and acrylate, chemical cross-linking can be used to chemically bond between polyurethane and acrylate to improve its stability. For chemical cross-linking, carbonyl-containing diacetone acryloyl monomers are mostly used, and cross-linking is formed by dehydration reaction to obtain a cross-linking system. There are certain restrictions on the cross-linking between them. In the preparation process of conventional acrylate water repellent, an external low-molecular-weight emulsifier needs to be used. The addition of emulsifier will affect the water-repellent effect of the water-repellent agent, and at the same time, it is soluble in water, causing harm to the environment. For example, the emulsifier polyoxyethylene octyl phenol ether has poor biodegradability, and some countries and regions have begun to limit its dosage. In addition, the waste liquid discharge, dissolving and washing process during the preparation and use of the water repellent agent and the process of treating the fabric during consumption will cause certain pollution to the environment. Self-emulsification is achieved by introducing hydrophilic moieties, such as groups ionizable as anions or cations. Self-emulsifying water repellent can effectively avoid product defects caused by external emulsifiers. The fabric is negatively charged in water, so the anionic products cannot be closely adsorbed with the fabric, and the anionic water repellent has high requirements on water quality, which limits its wider application. At present, water-based polyurethanes are mostly anionic polyurethanes, and there is no report on cationic polyurethane-acrylic water repellents. In addition, the existing conventional non-fluorine water repellent also has the problem of poor washing fastness, and generally the washing fastness is not more than 10 times of washing in an ordinary household washing machine.

Therefore, there is an urgent market demand to provide a high-performance cationic polyurethane-acrylate water repellent.

SUMMARY OF THE INVENTION

In order to solve the above problems and broaden the application scope of the polyurethane-acrylate water repellent, the present invention constructs a polyurethane-acrylate water repellant with a cationic structure. Polyurethane-acrylate water repellent, namely self-emulsifying cationic high-fastness aqueous emulsion, was prepared by introducing unsaturated monomer-terminated, cationizable monomer and cross-linkable monomer.

The first object of the present invention is to provide a method for preparing a cationic polyurethane-acrylate water-repellent agent, the method comprising:

(1) Utilize polymer polyol, partial alcohol amine and diisocyanate to prepare polyurethane prepolymer;

(2) the polyurethane prepolymer and the remaining alcohol amine and unsaturated alcohol obtain a double bond-terminated polyurethane molecular main chain;

(3) self-emulsification by adding water to obtain water-based cationic polyurethane self-emulsion;

(4) polymerizing the polyurethane self-emulsion and the acrylate monomer to construct a graft copolymer to obtain a cationic polyurethane-acrylate water repellent.

In an embodiment of the present invention, in the step (1), the molar ratio of isocyanate groups (diisocyanate monomers) to hydroxyl groups (polymer polyols, alcohol amines, unsaturated alcohols) is 1.2-2.2.

In one embodiment of the present invention, the polymer polyol accounts for 84-90% of the total mass of the hydroxyl-containing monomers (polymer polyol, alcohol amine, unsaturated alcohol).

In an embodiment of the present invention, the alcohol amine accounts for 2-8% of the total mass of the hydroxyl-containing monomer (polymer polyol, alcohol amine, unsaturated alcohol).

In an embodiment of the present invention, the unsaturated alcohol accounts for 2-8% of the total mass of the hydroxyl-containing monomer (polymer polyol, alcohol amine, unsaturated alcohol).

In an embodiment of the present invention, the self-emulsification in the step (3) is obtained by adding a neutralizer and water, and stirring according to a solid content of 15% to 40%.

In an embodiment of the present invention, in the step (4), the mass ratio of the acrylate monomer to the solid content of the polyurethane self-emulsion is (1-2):1.

In one embodiment of the present invention, the step (4) is to introduce the acrylate monomer by the pre-swelling method, which is to add the acrylate monomer into the self-emulsifying cationic polyurethane emulsion, and fully stir for a certain period of time to obtain the swelling solution The polymerization initiated by the initiator is then carried out.

In one embodiment of the present invention, the diisocyanates include isophorone diisocyanate, toluene diisocyanate, diphenylmethane diisocyanate, lysine diisocyanate, 1,6-hexamethylene diisocyanate, 1,4- One or more of benzene diisocyanate, 1,5-naphthalene diisocyanate, dicyclohexylmethane diisocyanate, and hexamethylene diisocyanate.

In an embodiment of the present invention, the polymer polyol includes a mixture of one or more of polyether diol and polyester diol with a molecular weight of 200-1000.

In an embodiment of the present invention, the alcohol amine includes one of diethanolamine, triethanolamine, N-methyldiethanolamine, tert-butyldiethanolamine, dimethyldiethanolamine, and N-ethyldiethanolamine or variety.

In an embodiment of the present invention, the unsaturated alcohol includes one or both of hydroxyethyl acrylate and hydroxyethyl methacrylate.

In one embodiment of the present invention, the neutralizing agent includes one or more of glacial acetic acid, hydrochloric acid, lactic acid, and dimethylmercaptopropionic acid.

In one embodiment of the present invention, the acrylate-based alkane monomers include methyl acrylate, butyl acrylate, hexyl acrylate, octyl acrylate, decyl acrylate, dodecyl acrylate, tetradecyl acrylate, and ten acrylate. Hexyl acrylate, octadecyl acrylate, methyl methacrylate, butyl methacrylate, hexyl methacrylate, octyl methacrylate, decyl methacrylate, dodecyl methacrylate, tetradecyl methacrylate One or more of esters, cetyl methacrylate, and octadecyl methacrylate.

In one embodiment of the present invention, the acrylate-based functional monomer includes one or more of glycidyl acrylate, glycidyl methacrylate, hydroxyethyl acrylate, and hydroxyethyl methacrylate .

In one embodiment of the present invention, the initiator includes one or more of azobisisobutyronitrile, azobisisoheptanenitrile, potassium persulfate, ammonium persulfate, and dibenzoyl peroxide.

In one embodiment of the present invention, the preparation method of the water-based cationic polyurethane self-emulsion in the step (3) specifically includes:

According to the ratio of isocyanate groups to hydroxyl groups of 1.2 to 2.2, the polymer polyols (accounting for 84% to 90% of the total mass of polymer polyols, alcohol amines and unsaturated alcohols), alcohol amines (accounting for polymer polyols, alcohol 2%～8% of the total mass of amines, unsaturated alcohols), unsaturated alcohols (2%～8% of the total mass of polymer polyols, alcohol amines, unsaturated alcohols) are vacuum dried at 50-60℃ to remove water ; Take part of the alcohol amine and add the polymer polyol, add dibutyl tin dilaurate (accounting for 0.2% of the mass of the total monomers participating in the reaction), and under nitrogen protection, at a temperature of 50-70 ° C, slowly add diisocyanate, using di- The -NCO value in the reaction system is measured by the butylamine method. When the theoretical value is reached (the theoretical residual amount of isocyanate groups is less than or equal to 32%), the temperature is raised to 60-80 ° C, and the remaining alcohol amine is added to measure the -NCO content in the reaction system to reach the theoretical value. unsaturated alcohol is added until the -NCO content in the reaction system reaches the theoretical value (theoretical residual amount of isocyanate ≤ 0.5%), and the unsaturated double bond is terminated. The temperature of the reaction system is lowered to room temperature, a neutralizing agent (neutralization degree 100%-120%) is added to adjust the reaction pH (pH=6-7), deionized water is added according to the solid content of the product mass of 15%-40% and stirred at high speed Self-emulsification to obtain water-based cationic polyurethane self-emulsion.

In one embodiment of the present invention, the preparation method of the cationic polyurethane-acrylate water repellent in the step (4) specifically includes:

Add the self-emulsifying cationic polyurethane emulsion dropwise to the acrylate monomer (the mass ratio of the total mass of the acrylate monomer to the solid content in the polyurethane self-emulsion is (1～2):1) at 40～50℃, And after stirring at 3000-5000r/min speed for 15-20min, and stirring at 500-1000r/min speed for 12 hours, the acrylate monomer pre-swelling liquid of cationic polyurethane is obtained. Add a certain amount of initiator (the amount of the initiator is 0.1% to 1% of the amount of the acrylate monomer), and keep the temperature at 70 to 80°C for 2 to 3 hours under the protection of nitrogen atmosphere. Natural cooling to 30-40 DEG C for heat preservation and discharging to obtain a cationic polyurethane-acrylate water repellent.

The second object of the present invention is to provide a cationic polyurethane-acrylate water-repellent agent prepared by the above-mentioned method.

The third object of the present invention is to provide a cationic polyurethane-acrylate water-repellent agent, and the structure of the cationic polyurethane-acrylate water-repellent agent includes the structure shown in formula (I):

A _a -B _b -CD _d -ED _m -CB _n -A _i

Formula 1)

Where a, b, d, m, n, i are natural numbers from 1 to 100, the general chemical structure of A is (2), the general chemical structure of B is (3), and C is the alkyl moiety of an unsaturated alcohol , the general chemical structure of D is (4), and the general chemical structure of E is (5); the arrangement positions of B, C, D, and E are not fixed;

Wherein R ₁ is a carbon chain with 1-18 carbon atoms; R ₂ is H or -CH ₃ ; R ₃ is H or -CH ₃ ; R ₄ is glycidyl ester or hydroxyethyl ester; wherein R ₅ is two The non-isocyanato group of the isocyanate monomer; R ₆ is the non-hydroxyl group of the polyol organic compound; wherein R ₇ , R ₈ and R ₉ are alkane groups.

The fourth object of the present invention is to provide a method for hydrophobic treatment of fabrics, the method is to treat fabrics by dipping and treating them in a treatment solution, and then rolling and baking; the treatment includes the above-mentioned cationic polyurethane-acrylate water repellent

The fifth object of the present invention is to provide a hydrophobic fabric, which comprises the above-mentioned cationic polyurethane-acrylate water-repellent agent, or is prepared by the above-mentioned hydrophobic treatment method.

The present invention has the following beneficial effects:

1. The method of the present invention adopts the copolymerization of an unsaturated double bond-terminated cationic polyurethane and an acrylate to prepare a water repellent. Polyurethane and acrylate are connected by chemical bonds, which improves the compatibility of polymer molecular segments. During use, the polymer will not undergo phase separation, and the film-forming effect is better.

2. The method of the present invention introduces a hydrophilic alcohol amine during prepolymerization, and competitive polymerization occurs. The diisocyanate reacts with the alcohol amine first, and then reacts with the polymer diol, so that the length of the segment between the two hydrophilic groups is shorter. The cationic hydrophilic groups are relatively uniformly distributed in the prepolymer.

3. The method of the present invention adopts the method of introducing cationizable monomers in the polyurethane polymerization process to implement polymer self-emulsification, which avoids the reduction of water-repellent effect and the environment caused by the emulsification of conventional acrylate water-repellent agents by adding low-molecular-weight surfactants. pollution, etc. The cationic water-repellent agent avoids the problem that conventional anionic products cannot be tightly adsorbed with the fabric (exhibits negative charge), and is more conducive to the uniform film formation of the water-repellent agent on the surface of the fabric.

4. The polymer polyol monomer in the cationic polyurethane-acrylate water repellent prepared by the method of the present invention can provide the flexibility of the product, the diisocyanate unit can provide the strength, the alcohol amine can provide the self-emulsifying hydrophilicity of the product, and the polyurethane main chain The soft and hard molecular segments in the structure can endow the fabric with good low temperature resistance, flexibility and bonding strength. Acrylate alkane monomers can effectively reduce surface energy and play a role in water repellency. The introduction of acrylate monomers containing cross-linking functional groups in the molecular structure of the water repellent can establish cross-linking between polymer molecules and chemical bonds with the fabric, giving the product higher fastness. It overcomes the poor fastness of conventional water-repellent products and the need to add a cross-linking agent to the fabric finishing solution to improve the fastness.

5. The cationic polyurethane-acrylate water-repellent agent prepared by the present invention avoids the problems of environmental pollution and bioaccumulation toxicity caused by the use of fluorine-containing water-repellent agents, and at the same time improves the hot, sticky and cold of acrylate monomers to a certain extent. The disadvantages of brittleness, poor flexibility, and solvent resistance. The structural advantages of polyurethane and acrylate complement each other, and the physical and mechanical properties, water resistance and thermodynamic properties of the finished fabric are improved.

6. The water-repellent finishing of the fabric by the water-repellent agent of the present invention is simple in operation and more energy-saving. The prepared water-repellent agent is near neutral, the fabric damage after finishing is small, the product has good uniformity, and a layer of water-repellent film can be formed on the surface of the fabric, thereby greatly improving the water-repellent capability of the fabric. And the addition of polyurethane can give the fabric a soft and plump hand. In addition, its VOC emission is extremely low, which is suitable for environmental protection requirements. In general, the finished fabric has good water-repellent, soft, breathable, stain-resistant, and wash-resistant properties.

Description of drawings

Figure 1: Static water contact angle plot of treated fabrics.

Detailed ways

The present invention will be further described below in conjunction with specific examples, and the examples are only used to explain the present invention, and are not intended to limit the scope of the present invention.

Example 1:

Follow the steps below to prepare a cationic polyurethane-acrylate water repellant and finish fabrics:

Preparation of cationic polyurethane self-emulsion:

According to the ratio of isocyanate group to hydroxyl group of 1.2:1, polytetrahydrofuran (Mn=850) (accounting for 90% of the total mass of polytetrahydrofuran (Mn=850), N-methyldiethanolamine, and hydroxyethyl acrylate), N- Methyldiethanolamine (accounting for polytetrahydrofuran (Mn=850), N-methyldiethanolamine, 2% of the total mass of hydroxyethyl acrylate), hydroxyethyl acrylate (accounting for polytetrahydrofuran (Mn=850), N-methyl acrylate 8% of the total mass of diethanolamine and hydroxyethyl acrylate) under vacuum drying at 50 ° C to remove water;

Take 1/3 N-methyldiethanolamine and add polytetrahydrofuran, add dibutyltin dilaurate (accounting for 0.2% of the mass of the total monomers participating in the reaction), under nitrogen protection, at a temperature of 50 ° C, slowly add isophorone diisocyanate dropwise , using the di-n-butylamine method to measure the -NCO content, when the -NCO value in the measured reaction system reaches the theoretical value (the theoretical residual amount of isocyanate groups is less than or equal to 32%), the temperature is raised to 60 ° C, and the remaining N-methyldiethanolamine is added. , measure the -NCO content in the reaction system reaches the theoretical value (theoretical residual amount of isocyanate ≤ 7%) and then add hydroxyethyl acrylate until the -NCO content in the reaction system reaches the theoretical value (theoretical residual amount of isocyanate ≤ 0.5%) , to achieve unsaturated double bond end capping. The temperature of the reaction system was lowered to room temperature, the neutralizing agent acetic acid (neutralization degree 100%) was added to adjust the reaction pH (pH=6～7), deionized water was added according to the solid content of the product mass 15% and stirred at high speed (1000r/min) Self-emulsification to obtain water-based cationic polyurethane self-emulsion.

Acrylate monomers react with water-based polyurethane self-emulsion to prepare water repellent:

The self-emulsifying cationic polyurethane emulsion was added dropwise to the acrylate monomer (the mass ratio of octadecyl acrylate:glycidyl acrylate was 95:5, and the total mass of the acrylate monomer was equal to the content of the polyurethane self-emulsion at 40°C). The mass ratio of solid content is 1:1), and after stirring at 3000 r/min for 15 min, and then at 500 r/min for 12 hours, a cationic polyurethane acrylate monomer pre-swelling solution is obtained. Add initiator ammonium persulfate (the amount of initiator is 0.1% of the amount of acrylate monomer), and keep the temperature at 70° C. for 3 hours under the protection of nitrogen atmosphere. Naturally cooled to 30°C for heat preservation and discharging to obtain a cationic polyurethane-acrylate water repellent.

Cationic polyurethane-acrylate water repellent treated fabrics:

The content of the above-mentioned cationic polyurethane-acrylate water-repellent agent is 100 g/L, and the fabric is dipped with a nip rate of 100%, pre-baked at 100° C. for 2 minutes, and then baked at 140° C. for 3 minutes. The relevant parameters of the treated fabrics are shown in Table 1.

Example 2:

The water-based cationic polyurethane self-emulsion was obtained with reference to the conditions of Example 1, and the mass ratio of the total mass of the acrylate monomer to the solid content in the polyurethane self-emulsion was replaced from 1:1 to 2:1 and 1.5:1 respectively, and other conditions remained unchanged. , the cationic polyurethane-acrylate water repellent was prepared.

Referring to the fabric treatment conditions of Example 1, the obtained cationic polyurethane-acrylate water repellent was used to treat the fabric. The relevant parameters of the treated fabric are shown in Table 1.

Table 1 Relevant parameters of the treated fabric

Note: The CIE whiteness value of the fabric before treatment is 75.8, the softness is 66.19, the breaking strength in the warp direction is 720N, and the breaking strength in the weft direction is 480N. 2A test standard. One AATCC 2A standard soap wash is equivalent to 5 washes of an ordinary household washing machine.

Product hydrophobic effect: It can be seen from Table 1 that the cationic polyurethane-acrylate water repellent prepared under the mass ratio of the total mass of the acrylate monomer to the solid content of the polyurethane self-emulsion has a good water repellency effect on the fabric after finishing. High hydrostatic pressure resistance, excellent pilling resistance, good fabric whiteness and high breaking strength.

Product washing fastness: It can be seen from Table 1 that the fabrics prepared with the cationic polyurethane-acrylate water repellent prepared under the mass ratio of the total mass of acrylate monomers to the solid content of the polyurethane self-emulsion are treated with an amount equivalent to 25%. After the second household washing machine washing, the static water contact angle (hydrophobicity) of the fabric is higher than 125°, and has high hydrophobicity. .

Repeatability of product hydrophobic effect: The cationic polyurethane-acrylate water repellent prepared according to acrylate monomers in different proportions, after 10 batches of finishing, the range error of the static water contact angle of each finishing fabric is ±2 °, it can be seen from the contact angle data that the hydrophobic effect of the treated fabric is reproducible.

Example 3:

The cationic polyurethane-acrylate water repellent was prepared with reference to the conditions of Example 1, and the water repellent content in the fabric finishing process was replaced by 100g/L to 80g/L, 60g/L, 40g/L, 20g/L, and other The conditions were unchanged, and the fabrics were treated separately. The relevant parameters of the treated fabrics are shown in Table 2.

Table 2 Relevant parameters of fabrics after impregnation treatment with different water repellent contents

Note: The CIE whiteness value of the fabric before treatment is 75.8, the softness is 66.19, the breaking strength in the warp direction is 720N, and the breaking strength in the weft direction is 480N. 2A test standard. One AATCC 2A standard soap wash is equivalent to 5 washes of an ordinary household washing machine.

Product hydrophobic effect: It can be seen from Table 2 that the cationic polyurethane-acrylate water repellent prepared under the same conditions uses different amounts of water repellent when finishing fabrics, and the obtained fabrics have good water repellency effects, high hydrostatic pressure resistance, Excellent pilling, good fabric whiteness and high breaking strength.

Product washing fastness: It can be seen from Table 2 that the cationic polyurethane-acrylate water repellent prepared under the same conditions uses different amounts of water repellent when finishing fabrics. The water contact angles (hydrophobicity) are all higher than 125°, and have high hydrophobicity, indicating that the fabrics have high washing fastness after the fabrics are treated with the water-repellent agent prepared by the present invention.

Repeatability of product hydrophobic effect: The polyurethane-acrylate water repellent prepared according to the acrylate monomer in different proportions, after 10 batches of finishing, the range error of the static water contact angle of each finishing fabric is ±2°, It can be seen from the contact angle data that the hydrophobic effect of the treated fabric is reproducible.

Embodiment 4:

Preparation of cationic polyurethane self-emulsion:

According to the ratio of isocyanate group to hydroxyl group of 2.2:1, polyester diol (Mn=1000) (accounting for 84% of the total mass of polyester diol (Mn=1000), triethanolamine and hydroxyethyl methacrylate), Triethanolamine (8% of the total mass of polyester diol (Mn=1000), triethanolamine, hydroxyethyl methacrylate), hydroxyethyl methacrylate (accounting for polyester diol (Mn=1000), triethanolamine , 8% of the total mass of hydroxyethyl methacrylate) under vacuum drying at 60 ° C to remove water;

Take 1/3 triethanolamine and add polyester diol, add dibutyltin dilaurate (accounting for 0.2% of the total monomer mass participating in the reaction), under nitrogen protection, slowly add toluene diisocyanate dropwise at a temperature of 70 ° C, using di-n- The -NCO content was determined by the butylamine method. When the -NCO value in the reaction system reached the theoretical value (the theoretical residual amount of isocyanate ≤ 32%), the temperature was raised to 80 ° C, and the remaining triethanolamine was added to determine the -NCO content in the reaction system. After reaching the theoretical value (theoretical residual amount of isocyanate ≤ 7%), add hydroxyethyl methacrylate until the -NCO content in the reaction system reaches the theoretical value (theoretical residual amount of isocyanate group ≤ 0.5%) to realize the unsaturated double bond end capped. The temperature of the reaction system was lowered to room temperature, the neutralizing agent hydrochloric acid (neutralization degree 120%) was added to adjust the reaction pH (pH=6～7), deionized water was added according to the solid content of the product mass 40% and stirred at high speed (1000r/min) Self-emulsification to obtain water-based cationic polyurethane self-emulsion.

Acrylate monomers react with water-based polyurethane self-emulsion to prepare water repellent:

At 50°C, the self-emulsifying cationic polyurethane emulsion was added dropwise to the acrylate monomers (the mass ratio of cetyl acrylate: methyl methacrylate: hydroxyethyl acrylate was 100:120:10, and the total amount of acrylate monomers was 100:120:10). The mass ratio of the mass to the solid content in the polyurethane self-emulsion is 2:1), and after stirring at 5000 r/min for 20 min, and then at 1000 r/min for 12 hours, a cationic polyurethane acrylate monomer pre-swelling solution is obtained . Add the initiator potassium persulfate (the amount of the initiator is 1% of the amount of the acrylate monomer), and keep the temperature at 80° C. for 2 hours under the protection of nitrogen atmosphere. Naturally cooled to 40°C for heat preservation and discharging to obtain a cationic polyurethane-acrylate water repellent.

Cationic polyurethane-acrylate water repellent treated fabrics:

The content of the above-mentioned cationic polyurethane-acrylate water-repellent agent is 40 g/L, and the fabric is dipped with a nip rate of 80%, pre-baked at 105° C. for 2 minutes, and then baked at 150° C. for 2 minutes. The relevant parameters of the treated fabrics are shown in Table 3.

Example 5:

Preparation of cationic polyurethane self-emulsion:

According to the ratio of isocyanate group to hydroxyl group of 1.4:1, polyoxyethylene glycol (Mn=400) (accounting for 88% of the total mass of polyoxyethylene glycol (Mn=400), diethyldiethanolamine and hydroxyethyl acrylate %), diethyldiethanolamine (accounting for polyethylene oxide diol (Mn=400), diethyl diethanolamine, 6% of the total mass of hydroxyethyl acrylate), hydroxyethyl acrylate (accounting for polyethylene oxide diol ( Mn=400), diethyldiethanolamine, 6% of the total mass of hydroxyethyl acrylate) at 60 ° C under vacuum drying to remove water;

Take 1/3 diethyldiethanolamine, add polyethylene oxide diol, add dibutyltin dilaurate (accounting for 0.2% of the total monomer mass participating in the reaction), under nitrogen protection, at a temperature of 70 ° C, slowly add 1,6 -Hexylene diisocyanate, use the di-n-butylamine method to measure the -NCO content, when the -NCO value in the measured reaction system reaches the theoretical value (theoretical residual amount of isocyanate ≤ 32%), increase the temperature to 80 ° C, add the remaining diethyl ether diethanolamine, measure the -NCO content in the reaction system reaches the theoretical value (theoretical residual amount of isocyanate ≤ 7%) and then add hydroxyethyl acrylate until the -NCO content in the reaction system reaches the theoretical value (theoretical residual amount of isocyanate ≤ 7%) 0.5%) to achieve unsaturated double bond end capping. The temperature of the reaction system was lowered to room temperature, the neutralizing agent lactic acid (neutralization degree 110%) was added to adjust the reaction pH (pH=6～7), deionized water was added according to the solid content of the product mass 30% and stirred at high speed (1000r/min) Self-emulsification to obtain water-based cationic polyurethane self-emulsion.

Acrylate monomers react with water-based polyurethane self-emulsion to prepare water repellent:

At 40°C, the self-emulsifying cationic polyurethane emulsion was added dropwise to the acrylate monomer (tetradecyl acrylate: octadecyl acrylate: butyl methacrylate: hydroxyethyl methacrylate in a mass ratio of 100:100: 120:2, the mass ratio of the total mass of the acrylate monomer to the solid content in the polyurethane self-emulsion is 1.5:1), and after stirring at 5000r/min for 20min, then at 1000r/min for 12 hours to obtain cationic type Polyurethane acrylate monomer pre-swelling solution. Add the initiator azobisisobutyronitrile (the amount of the initiator is 0.5% of the amount of the acrylate monomer), and keep the temperature at 75° C. for 3 hours under the protection of nitrogen atmosphere. Naturally cooled to 30°C for heat preservation and discharging to obtain a cationic polyurethane-acrylate water repellent.

Cationic polyurethane-acrylate water repellent treated fabrics:

The content of the above-mentioned cationic polyurethane-acrylate water-repellent agent is 60 g/L, and the fabric is impregnated with 150% rolling stock, pre-baked at 110° C. for 2 minutes, and then baked at 150° C. for 2 minutes. The relevant parameters of the treated fabrics are shown in Table 3.

Example 6:

Preparation of cationic polyurethane self-emulsion:

According to the ratio of isocyanate group to hydroxyl group of 1.5:1, polypropylene glycol (Mn=400) (accounting for 85% of the total mass of polypropylene glycol (Mn=400), N-methyldiethanolamine, and hydroxyethyl methacrylate), N-methyldiethanolamine (accounting for polypropylene glycol (Mn=400), N-methyldiethanolamine, 8% of the total mass of hydroxyethyl methacrylate), hydroxyethyl methacrylate (accounting for polypropylene glycol (Mn=400) ), N-methyldiethanolamine, 7% of the total mass of hydroxyethyl methacrylate) at 50 ° C under vacuum drying to remove water;

Take 1/3 N-methyldiethanolamine, add polypropylene glycol, add dibutyltin dilaurate (accounting for 0.2% of the total monomer mass participating in the reaction), under nitrogen protection, at a temperature of 70 ° C, slowly add isophorone diisocyanate dropwise , using the di-n-butylamine method to measure the -NCO content, when the -NCO value in the measured reaction system reaches the theoretical value (the theoretical residual amount of isocyanate ≤ 32%), the temperature is raised to 75 ° C, and the remaining N-methyldiethanolamine is added. , measure the -NCO content in the reaction system reaches the theoretical value (theoretical residual amount of isocyanate ≤ 7%) and then add hydroxyethyl methacrylate until the -NCO content in the reaction system reaches the theoretical value (theoretical residual amount of isocyanate ≤ 0.5 %) to achieve unsaturated double bond end capping. The temperature of the reaction system was lowered to room temperature, and the neutralizing agent lactic acid (neutralization degree 100%) was added to adjust the reaction pH (pH=6～7), and deionized water was added according to the solid content of the product mass of 20% and stirred at high speed (1000r/min) Self-emulsification to obtain water-based cationic polyurethane self-emulsion.

Acrylate monomers react with water-based polyurethane self-emulsion to prepare water repellent:

At 40°C, the self-emulsifying cationic polyurethane emulsion was added dropwise to the acrylate monomers (octadecyl methacrylate: dodecyl acrylate: glycidyl methacrylate mass ratio 100:150:10, acrylate monomer The mass ratio of the total body mass to the solid content in the polyurethane self-emulsion is 1:1), and after stirring at 3000 r/min for 20 min, and then stirring at 500 r/min for 12 hours, the acrylate monomer of cationic polyurethane is obtained. swelling fluid. Add the initiator potassium persulfate (the amount of the initiator is 0.5% of the amount of the acrylate monomer), and keep the temperature at 80° C. for 2 hours under the protection of nitrogen atmosphere. Naturally cooled to 30°C for heat preservation and discharging to obtain a cationic polyurethane-acrylate water repellent.

Cationic polyurethane-acrylate water repellent treated fabrics:

The content of the above-mentioned cationic polyurethane-acrylate water-repellent agent is 20 g/L, and the fabric is impregnated with 100% rolling stock, pre-baked at 100° C. for 2 minutes, and then baked at 140° C. for 5 minutes. The relevant parameters of the treated fabrics are shown in Table 3.

Example 7:

Preparation of cationic polyurethane self-emulsion:

According to the ratio of isocyanate group to hydroxyl group of 1.8:1, poly-ε-caprolactone diol (Mn=1000) (accounting for poly-ε-caprolactone diol (Mn=1000), tert-butyldiethanolamine, 90% of the total mass of hydroxyethyl methacrylate), tert-butyl diethanolamine (accounting for the total mass of poly-ε-caprolactone diol (Mn=1000), tert-butyl diethanolamine, hydroxyethyl methacrylate 7%), hydroxyethyl methacrylate (3% of the total mass of poly-ε-caprolactone diol (Mn=1000), tert-butyl diethanolamine, hydroxyethyl methacrylate) under vacuum at 50°C drying to remove water;

Take 1/3 tert-butyldiethanolamine, add poly-ε-caprolactone diol, add dibutyltin dilaurate (accounting for 0.2% of the mass of the total monomers participating in the reaction), under nitrogen protection, at a temperature of 70 ° C, slowly drip Add 1,4-phenylenediisocyanate, and use the di-n-butylamine method to measure the -NCO content. When the -NCO value in the reaction system reaches the theoretical value (theoretical residual amount of isocyanate ≤ 32%), increase the temperature to 75°C, Add the remaining N-methyldiethanolamine, measure the -NCO content in the reaction system to reach the theoretical value (the theoretical residual amount of isocyanate ≤ 7%) and then add hydroxyethyl methacrylate until the -NCO content in the reaction system reaches the theoretical value ( The theoretical residual amount of isocyanate group is less than or equal to 0.5%) to realize the end capping of unsaturated double bonds. The temperature of the reaction system was lowered to room temperature, the neutralizing agent dimethylmercaptopropionic acid (120% neutralization degree) was added to adjust the reaction pH (pH=6～7), deionized water was added according to the solid content of the product mass 30% and stirred at high speed (1000r/min) self-emulsification to obtain water-based cationic polyurethane self-emulsion.

Acrylate monomers react with water-based polyurethane self-emulsion to prepare water repellent:

At 50°C, the self-emulsifying cationic polyurethane emulsion was added dropwise to the acrylate monomers (tetradecyl methacrylate: octyl methacrylate: hydroxyethyl methacrylate in a mass ratio of 100:110:5, acrylates The mass ratio of the total mass of the monomer to the solid content in the polyurethane self-emulsion is 1.2:1), and after stirring at 3000r/min for 20min, and then stirring at 500r/min for 12 hours, the acrylate monomer of cationic polyurethane is obtained Pre-swelling solution. Add the initiator potassium persulfate (the amount of the initiator is 0.5% of the amount of the acrylate monomer), and keep the temperature at 80° C. for 2 hours under the protection of nitrogen atmosphere. Naturally cooled to 30°C for heat preservation and discharging to obtain a cationic polyurethane-acrylate water repellent.

Cationic polyurethane-acrylate water repellent treated fabrics:

The content of the above-mentioned cationic polyurethane-acrylate water-repellent agent is 80 g/L, and the fabric is impregnated with 100% rolling stock, pre-baked at 100° C. for 2 minutes, and then baked at 150° C. for 5 minutes. The relevant parameters of the treated fabrics are shown in Table 3.

Comparative Example 1:

Prepare acrylic water repellent according to the following steps:

Dissolve the emulsifier sodium dodecyl sulfate (SDS) and polyoxyethylene stearate (AEO-18) in deionized water to prepare an emulsion (SDS: AEO-18=1:4, mass ratio, the dosage is 10% of the total mass of the monomer). Under high-speed stirring (5000r/min), add octadecyl acrylate and methyl methacrylate (the mass ratio of monomers is 1:1, and the total mass of monomers is 20% of the mass of the emulsion) into the emulsion system, and carry out Pre-emulsified. 50% of the pre-emulsion was added to the reaction vessel, the temperature was raised to 75°C, and the initiator potassium persulfate (the amount of the initiator was 0.6%) was added dropwise under nitrogen environmental protection, and the remaining pre-emulsion was added after continuing the reaction for 2 hours. Incubate for 2h, cool down to room temperature, cool and discharge.

Preparation of water repellent finishing fabric method:

The water repellent content was 80 g/L, and the fabric was impregnated with 100% rolling stock, pre-baked at 105 °C for 2 minutes, and then baked at 140 °C for 5 minutes. The relevant parameters of the treated fabrics are shown in Table 3.

Comparative Example 2:

Prepare anionic polyurethane-modified acrylate water repellent according to the following steps:

Referring to Example 1, only the cationizable alcohol amine (N-methyldiethanolamine) was replaced with anionizable dimethylol butyric acid, and the neutralizing agent triethylamine was mixed to prepare an anionic polyurethane modified acrylate. Water repellent.

Preparation of water repellent finishing fabric method:

The fabric finishing method is the same as that in Example 1, and the relevant parameters of the treated fabric are shown in Table 3.

Comparative Example 3:

With reference to Example 1, change the N-methyldiethanolamine adding mode, do not add alcohol amine during prepolymerization, only add completely during chain extension in the second step:

Polytetrahydrofuran, dibutyltin dilaurate (accounting for 0.2% of the mass of the total monomers involved in the reaction), under nitrogen protection, slowly add isophorone diisocyanate dropwise at a temperature of 50 ° C, and use the di-n-butylamine method to determine the -NCO content , when the -NCO value in the measurement reaction system reaches the theoretical value (the theoretical residual amount of isocyanate group is less than or equal to 32%), the temperature is raised to 60 ° C, N-methyldiethanolamine is added, and the -NCO content in the measurement reaction system reaches the theoretical value ( The theoretical residual amount of isocyanate groups is less than or equal to 7%) and then hydroxyethyl acrylate is added until the -NCO content in the reaction system reaches the theoretical value (theoretical residual amount of isocyanate groups is less than or equal to 0.5%) to achieve unsaturated double bond end capping. The temperature of the reaction system was lowered to room temperature, the neutralizing agent acetic acid (100% neutralization degree) was added to adjust the reaction pH (pH=6～7), deionized water was added according to the solid content of 15% of the product mass and stirred at high speed (1000r/min) Self-emulsification to obtain water-based cationic polyurethane self-emulsion.

Referring to the preparation conditions of the water repellent agent in Example 1, the polyurethane-acrylate water repellent agent was obtained and used for fabric treatment. The relevant parameters of the treated fabric are shown in Table 3.

Comparative Example 4:

With reference to Example 1, only the way of adding N-methyldiethanolamine was changed, and alcoholamine was completely added at one time during prepolymerization:

N-methyldiethanolamine, polytetrahydrofuran, dibutyltin dilaurate (accounting for 0.2% of the mass of the total monomers participating in the reaction), under nitrogen protection, at a temperature of 50 ° C, slowly add isophorone diisocyanate dropwise, increase the temperature At 60°C, hydroxyethyl acrylate was added to achieve end-capping of unsaturated double bonds. The temperature of the reaction system was lowered to room temperature, the neutralizing agent acetic acid (100% neutralization degree) was added to adjust the reaction pH (pH=6～7), deionized water was added according to the solid content of 15% of the product mass and stirred at high speed (1000r/min) Self-emulsification to obtain water-based cationic polyurethane self-emulsion.

Referring to the preparation conditions of the water repellent agent in Example 1, the polyurethane-acrylate water repellent agent was obtained and used for fabric treatment. The relevant parameters of the treated fabric are shown in Table 3.

Table 3 Fabric related parameters after treatment

Note: The CIE whiteness value of the fabric before treatment is 75.8, the softness is 66.19, the breaking strength in the warp direction is 720N, and the breaking strength in the weft direction is 480N. 2A test standard. One AATCC 2A standard soap wash is equivalent to 5 washes of an ordinary household washing machine.

Product hydrophobic effect: The hydrophobic performance data of the fabric treated with the water repellent agent are shown in Table 1-3. It can be seen from the comparison of Examples 1-7 and 1-4 that the cationic polyurethane-modified acrylates designed in the present invention are water-repellent. Agent-treated fabrics have better water repellency (contact angles are greater than 140°) and better breaking strength (low loss of strength) than those containing only acrylic water repellent and anionic polyurethane-modified acrylic water repellent. At the same time, compared with the process of adding alcohol amine at one time, the water-repellent agent prepared by adding alcohol amine in batches has better water-repellent effect.

Repeatability of the hydrophobic effect of the product: After 10 batches of finishing of the fabrics in Example 1, the range of the static water contact angle of each finishing fabric is 146±3°. It can be seen from the contact angle data that the hydrophobic effect of the treated fabrics is repeated. good sex.

Washing resistance: According to the standard of AATCC 61-2010 "Color Fastness to Washing", the washing fastness test of the fabric after finishing with water repellent emulsion is carried out. After washing, the static water contact angle of the fabric was measured. After the fabrics prepared in Examples 1-7 were washed by the equivalent of 25 times in a domestic washing machine, although the static contact angle decreased compared with that before soaping, the contact angles of the fabric samples were all greater than 130°, and the fabrics still had high hydrophobicity. , indicating that the water repellent has good washing resistance.

Breaking strength: With reference to GB/T 3923-2013 "Strip-like method for the determination of tensile strength and elongation at break of fabrics", the breaking strength of the fabrics before and after finishing with water repellent agent is tested. As can be seen from the data in Table 3, the breaking strength loss of the fabrics treated with the cationic polyurethane-acrylate water repellent is smaller.

The above are only preferred embodiments of the present invention. It should be pointed out that for those skilled in the art, without departing from the principles of the present invention, several improvements and modifications can be made. These improvements and modifications It should also be regarded as the protection scope of the present invention.

Claims (8)

1. a preparation method of cationic polyurethane-acrylate water repellent, is characterized in that, described method comprises: (1) Utilize polymer polyol, partial alcohol amine and diisocyanate to prepare polyurethane prepolymer; (2) polyurethane prepolymer and remaining alcohol amine, unsaturated alcohol obtain the main chain of polyurethane molecule containing terminal double bond; (3) self-emulsification by adding water to obtain water-based cationic polyurethane self-emulsion; (4) polymerizing the polyurethane self-emulsion and the acrylate monomer to construct a graft copolymer to obtain a cationic polyurethane-acrylate water repellent; The molar ratio of isocyanate to hydroxyl in the diisocyanate, polymer polyol, alcohol amine and unsaturated alcohol in the method is 1.2-2.2; In the step (4), the mass ratio of the solid content of the acrylate monomer to the polyurethane self-emulsion is (1～2):1; The alcoholamine includes one or more of diethanolamine, triethanolamine, N-methyldiethanolamine, tert-butyldiethanolamine, dimethyldiethanolamine, and N-ethyldiethanolamine. 2. according to the method described in claim 1, it is characterized in that, the addition amount of described polymer polyol accounts for 84-90% of the total mass of hydroxyl-containing monomer, and described hydroxyl-containing monomer is polymer polyol, alcohol Amines and unsaturated alcohols. 3. The method according to claim 1, characterized in that, in the method, the total amount of alcohol amine added accounts for 2-8% of the total mass of the hydroxyl-containing monomer. 4. The method according to claim 1, wherein the added amount of the unsaturated alcohol accounts for 2-8% of the total mass of the hydroxyl-containing monomer. 5 . A cationic polyurethane-acrylate water-repellent agent, characterized in that the cationic polyurethane-acrylate water-repellent agent is prepared by the method of any one of claims 1 to 4 . 6. A cationic polyurethane-acrylate water repellent, characterized in that the structure is formula (1): A _a -B _b -CD _d -ED _m -CB _n -A _i Formula 1) where a, b, d, m, n, i are natural numbers from 1 to 100, the general chemical structure of A is formula (2), the general chemical structure of B is formula (3), and C is an alkane of an unsaturated alcohol Base part, the general chemical structure of D is formula (4), and the general chemical structure of E is formula (5);

Wherein R ₁ is a carbon chain with 1-18 carbon atoms; R ₂ is H or -CH ₃ ; R ₃ is H or -CH ₃ ; R ₄ is glycidyl ester or hydroxyethyl ester; wherein R ₅ is two The non-isocyanato group of the isocyanate monomer; R ₆ is the non-hydroxyl group of the polyol organic compound; wherein R ₇ , R ₈ and R ₉ are alkane groups. 7. A fabric hydrophobic treatment method, characterized in that, the fabric is immersed in a treatment solution for treatment, and then rolled and baked to obtain; the treatment comprises the cationic polyurethane-acrylate repellent according to claim 5 or 6. Water agent. 8 . A hydrophobic fabric, characterized in that the fabric comprises the cationic polyurethane-acrylate water repellent according to claim 5 or 6 , or is prepared by the method according to claim 7 .

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