Waterborne polyurethane-urea dispersion with high brushing property as well as preparation method and application of waterborne polyurethane-urea dispersion

Abstract

The invention discloses a waterborne polyurethane-urea dispersion with high brushing property as well as a preparation method and application of the waterborne polyurethane-urea dispersion. According to the waterborne polyurethane-urea dispersion, more hydrophilic ion groups are enriched to the surfaces of latex particles by controlling reaction sites of an amine compound with hydrophilicity or hydrophilic potential and an isocyanate group, and fatty alcohol-polyoxyethylene ether with a specific structure is matched. The waterborne polyurethane-urea dispersion prepared by the preparation method disclosed by the invention is excellent in brushing performance, and can be applied to the field of adhesives, and other properties are slightly influenced.

Description

Technical Field

[0001] The invention belongs to the field of adhesives, and in particular relates to a highly brushable aqueous polyurethane-urea dispersion and a preparation method and application thereof. Background Art

[0002] Waterborne polyurethane dispersions are widely used in the adhesive field, especially shoe glue, due to their environmental friendliness and excellent physical and mechanical properties. Currently, the construction process of shoe glue is mainly brushing, and before gluing, it is usually necessary to use B powder to treat the surface of the rubber substrate. There are two main methods for B powder treatment: (1) Oil-based treatment agent - dissolve B powder in organic solvents such as butanone and ethyl acetate, then apply it to the rubber surface and dry it; (2) Water-based treatment agent - dissolve modified B powder in aqueous solutions such as phosphoric acid, malic acid, citric acid, then apply it to the rubber surface and dry it. The surface of the rubber substrate treated by the two methods is quite different, and the requirements for waterborne polyurethane dispersions are also completely inconsistent.

[0003] Existing technologies are all developed based on oil-based treatment agents. When used in combination with water-based treatment agents, their brushability is particularly poor, which seriously restricts their application. Summary of the Invention

[0004] In view of the above-mentioned deficiencies in the prior art, one of the objectives of the present invention is to provide an aqueous polyurethane-urea dispersion that can be used in combination with an aqueous treatment agent, which can be used as an adhesive.

[0005] Another object of the present invention is to provide a method for preparing the highly paintable aqueous polyurethane-urea dispersion.

[0006] Another object of the present invention is to provide applications of the highly paintable aqueous polyurethane-urea dispersion.

[0007] To achieve the above object, the present invention adopts the following technical solutions:

[0008] A highly brushable waterborne polyurethane-urea dispersion is prepared from raw materials comprising the following components:

[0009] S1, polyisocyanate;

[0010] S2, polymer polyol, having an average molecular weight of 800-4000 g / mol, for example, having an average molecular weight of 1000 g / mol, 2000 g / mol, 3000 g / mol, 4000 g / mol, etc.;

[0011] S3, a nonionic hydrophilic compound that can react with isocyanate;

[0012] S4. Hydrophilic or hydrophilic potential compounds containing 1 to 3 NCO reactive groups, wherein the amount of the bifunctional compound shall not be less than 90%, for example, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98%, 99%, etc.;

[0013] S5, a small molecule compound containing an amino group or a hydroxyl group with a functionality of 1 to 3, having an average molecular weight of 60-499 g / mol, for example, 80 g / mol, 100 g / mol, 150 g / mol, 200 g / mol, 250 g / mol, 300 g / mol, 350 g / mol, 400 g / mol, 450 g / mol, etc.;

[0014] S6. Hydrophilic or hydrophilic potential amino compounds containing 1-2 functional groups, of which the proportion of monofunctional compounds shall not be less than 80%, such as 85%, 90%, 95%, 99%, etc.;

[0015] S7, fatty alcohol polyoxyethylene ether, cloud point greater than 70 ° C, its general formula is RO (CH2CH2O) n H, R is saturated or unsaturated C 10 ~C 16 A hydrocarbon group, n = 20 to 60, such as 25, 30, 35, 40, 45, 50, 55, 60, etc.;

[0016] S8, water;

[0017] S9, an optional catalyst capable of catalyzing the reaction of isocyanate groups with hydroxyl groups;

[0018] S10. An organic solvent containing no group capable of reacting with isocyanate.

[0019] In the present invention, in the above-mentioned highly paintable aqueous polyurethane-urea dispersion, based on the total mass of components S1 to S7:

[0020] The amount of component S1 is 7.5-16.5 wt%, such as 8 wt%, 9 wt%, 10 wt%, 11 wt%, 12 wt%, 13 wt%, 14 wt%, 15 wt%, 16 wt%, etc., preferably 9-14 wt%;

[0021] The amount of component S2 is 72-90 wt%, such as 75 wt%, 78 wt%, 80 wt%, 82 wt%, 84 wt%, 85 wt%, 86 wt%, 88 wt%, etc., preferably 79-85 wt%;

[0022] The amount of component S3 is 0.1-2.1 wt%, such as 0.2 wt%, 0.5 wt%, 0.6 wt%, 0.8 wt%, 1.0 wt%, 1.3 wt%, 1.5 wt%, 1.6 wt%, 1.8 wt%, 1.9 wt%, etc., preferably 0.5-1.7 wt%;

[0023] The amount of component S4 is 0.5-2.3wt%, for example, 0.6wt%, 0.8wt%, 1.0wt%, 1.2wt%, 1.4wt%, 1.5wt%, 1.6wt%, 1.7wt%, 2.0wt%, 2.2wt%, etc., preferably 1.0-1.8wt%;

[0024] The amount of component S5 is 0.01-1.0 wt%, for example, 0.02 wt%, 0.03 wt%, 0.05 wt%, 0.08 wt%, 0.1 wt%, 0.2 wt%, 0.3 wt%, 0.4 wt%, 0.5 wt%, 0.6 wt%, 0.7 wt%, 0.8 wt%, 0.9 wt%, etc., preferably 0.03-0.5 wt%;

[0025] The amount of component S6 is 0.2-1.2 wt%, such as 0.3 wt%, 0.4 wt%, 0.5 wt%, 0.6 wt%, 0.7 wt%, 0.8 wt%, 0.9 wt%, 1.0 wt%, 1.1 wt%, etc., preferably 0.4-0.9 wt%;

[0026] The amount of component S7 is 1.0-6.0 wt%, for example, 1.5 wt%, 2.0 wt%, 2.5 wt%, 3.0 wt%, 3.5 wt%, 4.0 wt%, 4.5 wt%, 5.0 wt%, 5.5 wt%, etc., preferably 1.4-5 wt%.

[0027] Based on the total mass of components S1-S3:

[0028] The amount of component S9 is 0-2000ppm, for example, 10ppm, 50ppm, 100ppm, 300ppm, 500ppm, 800ppm, 1000ppm, 1500ppm, 1800ppm, etc., preferably 40-500ppm;

[0029] The amount of component S10 is 0.7-3.0 times the total mass of components S1-S3, for example, 0.8 times, 1.0 times, 1.2 times, 1.5 times, 1.8 times, 2.0 times, 2.2 times, 2.5 times, 2.8 times, 3.0 times, etc., preferably 1.0-2.2 times.

[0030] In the present invention, in component S1 of the above-mentioned highly brushable aqueous polyurethane-urea dispersion, the polyisocyanate includes, but is not limited to, one or more of hexamethylene diisocyanate, isophorone diisocyanate, 4,4-dicyclohexylmethane diisocyanate, 2,4-toluene diisocyanate, 2,6-toluene diisocyanate, pentamethylene diisocyanate, tetramethylene diisocyanate, dodecamethylene diisocyanate, 1,4-cyclohexane diisocyanate, 2,2-diphenylmethane diisocyanate, 4,4-diphenylmethane diisocyanate, 2,4-diphenylmethane diisocyanate, tetramethylxylene diisocyanate and p-xylylene diisocyanate, more preferably one or more of hexamethylene diisocyanate and isophorone diisocyanate.

[0031] In the present invention, in component S2 of the above-mentioned highly brushable aqueous polyurethane-urea dispersion, the polymer polyol is selected from one or more polymer diols with a number average molecular weight of 800-4000, preferably one or more linear or branched polyester polyols and polycarbonate polyols, and more preferably polyester diols prepared by reacting one or more of 1,4-butanediol, 1,5-pentanediol, 1,6-hexanediol, neopentyl glycol, and diethylene glycol with adipic acid.

[0032] In the present invention, in component S3 of the above-mentioned highly brushable aqueous polyurethane-urea dispersion, the nonionic hydrophilic compound is a monofunctional polyoxyethylene ether with a number average molecular weight of 200-8000 and an ethylene oxide number of 4-200, preferably polyethylene glycol monomethyl ether with a number average molecular weight of 500-3000 and an ethylene oxide number of 12-75.

[0033] In the present invention, in component S4 of the above-mentioned highly brushable aqueous polyurethane-urea dispersion, the hydrophilic compound containing an ionic group and 1-3 NCO reactive functional groups and / or the hydrophilic compound containing a potential ionic group and 1-3 NCO reactive functional groups, preferably, the NCO reactive group is an amino group or a hydroxyl group, the ionic group is a sulfonate and / or a carboxylate, and the potential ionic group is a sulfonic acid group and / or a carboxylic acid group; more preferably, the component S4 is selected from one or more of dihydroxycarboxylic acids and salts thereof, dihydroxysulfonic acids and salts thereof, diaminocarboxylic acids and salts thereof, and diaminosulfonic acids and salts thereof; further preferably, the component S4 is selected from one or more of dimethylolpropionic acid and alkali metal salts and / or ammonium salts thereof, N-(2-aminoethyl)-2-aminoethanesulfonic acid and alkali metal salts and / or ammonium salts thereof, N-(2-aminoethyl)-2-aminobutanesulfonic acid and alkali metal salts and / or ammonium salts thereof, and N-(2-aminoethyl)-3-aminopropanesulfonic acid and alkali metal salts and / or ammonium salts thereof;

[0034] In the present invention, in component S5 of the above-mentioned highly brushable aqueous polyurethane-urea dispersion, the aliphatic small molecule compound with a functionality of 1-3 containing primary or secondary amino groups is preferably one or more of isophoronediamine, 1,6-hexamethylenediamine, 4,4'-diaminodicyclohexylmethane, N-(2-hydroxyethyl)ethylenediamine, N-(β-aminoethyl)-γ-aminopropyltrimethoxysilane, ethanolamine and diethanolamine.

[0035] In the present invention, in component S6 of the highly brushable aqueous polyurethane-urea dispersion, the hydrophilic compound containing an ionic group and 1-2 NCO-reactive functional groups and / or the hydrophilic compound containing a potential ionic group and 1-2 NCO-reactive functional groups, preferably, the NCO-reactive group is an amino group or a hydroxyl group, the ionic group is a sulfonate and / or a carboxylate, and the potential ionic group is a sulfonic acid group and / or a carboxylic acid group; more preferably, component S6 is selected from aminocaproic acid and its alkali metal salts and / or ammonium salts, taurine and its alkali metal salts and / or ammonium salts;

[0036] In the present invention, in the component S7 of the above-mentioned highly brushable aqueous polyurethane-urea dispersion, the fatty alcohol polyoxyethylene ether has a cloud point greater than 70°C and a general formula of RO(CH2CH2O) n H, R is saturated or unsaturated C 10 ~C 16 The hydrocarbon group, preferably C 12 ~C 15 A hydrocarbon group, wherein n is 20 to 40.

[0037] In the present invention, the catalyst in component S9 of the highly brushable aqueous polyurethane-urea dispersion is a conventional catalyst in the art, such as dibutyltin dilaurate, stannous octoate, bismuth neodecanoate or bismuth 2-ethylhexanoate, triethylamine, 1,4-diazabicyclo-[2,2,2]-octane, etc., but is not limited thereto.

[0038] In the present invention, in the component S10 of the highly brushable aqueous polyurethane-urea dispersion, the organic solvent is a commonly used solvent in the art, such as acetone, butanone, tetrahydrofuran, toluene, etc., but not limited thereto.

[0039] Compared with the prior art, the technical solution of the present invention has the following beneficial effects:

[0040] The present application can significantly improve the brushability of waterborne polyurethane-urea by controlling the reaction site of hydrophilic or hydrophilic potential amine compounds with isocyanate groups to enrich more hydrophilic ionic groups on the surface of latex particles, and by matching specific structure of fatty alcohol polyoxyethylene ether, the matching application of waterborne polyurethane dispersion and waterborne rubber treating agent can be realized, the use of oily rubber treating agent is reduced, and the realization of "oil to water" in the field of shoe glue is promoted to a deeper level. DETAILED DESCRIPTION

[0041] The following examples are further illustrations of the present application and are not intended to limit the scope of the present application. Those skilled in the art will readily understand that modifications and equivalent substitutions can be made to the technical solutions of the present application without departing from the spirit and scope of the present application, and all of them should be covered in the scope of the claims of the present application. Within the scope of the present application, the above-mentioned technical features of the present application and the technical features specifically described in the following (such as examples) can be combined with each other to form new or preferred technical solutions.

[0042] I. Main raw material sources of examples:

[0043] Polyhexanedioic acid-1,4-butanediol ester diol, hydroxyl value = 56 mg KOH / g (WHP-204, Wanhua Chemical);

[0044] Polyhexanedioic acid-1,6 hexanediol-pentanediol ester diol, hydroxyl value = 74.8 mg KOH / g (WHP-1556, Wanhua Chemical);

[0045] Polyhexanedioic acid-1,4-butanediol ester diol, hydroxyl value = 40 mg KOH / g (WHP-104, Wanhua Chemical);

[0046] Polyhexanedioic acid-1,4-butanediol ester diol, hydroxyl value = 28 mg KOH / g (WHP-404, Wanhua Chemical);

[0047] Hexamethylene diisocyanate (Wannate@R HDI, Wanhua Chemical);

[0048] Isophorone diisocyanate (Wannate@R IPDI, Wanhua Chemical);

[0049] Catalyst: Bi@8108, industrial grade, American leading limited company;

[0050] Monofunctional polyethoxy ether, number average molecular weight 1200 (MPEG1200, CLARIANT);

[0051] Monofunctional polyethoxy ether, number average molecular weight 2000 (MPEG2000, CLARIANT);

[0052] Sodium N-(2-aminoethyl)-2-aminoethanesulfonate (Vestamin A95), Wanhua;

[0053] Hydroxyethylethylenediamine, also known as N-(2-hydroxyethyl)ethylenediamine, produced by BASF-Yangzi;

[0054] Isophorone diamine (IPDA), Wanhua Chemical;

[0055] 2-Aminoethanesulfonic acid, Guangzhou Mingtong Biotechnology Co., Ltd.;

[0056] Sodium 2-aminoethanesulfonate, Guangzhou Mingtong Biotechnology Co., Ltd.;

[0057] Emulsifier I: 15-S-40 (isotridecyl alcohol, EO number 40), 70% aqueous solution, Dow Chemical;

[0058] Emulsifier II: LCN-407, (isoundecyl alcohol, EO number 40), 70% aqueous solution, Clariant;

[0059] Emulsifier III: Tween 20 (sorbitan fatty acid ester ethylene oxide) Shanghai Bangjing Industrial;

[0060] Emulsifier IV: Novelution 380 (starting with isomeric tridecanol, EO number is 8), Sasol;

[0061] 2. Analytical instruments and test methods:

[0062] Brushability: Treat the rubber surface three times with a water-based treatment agent and dry it. Then place the rubber in an 80°C oven for 5 minutes. Immediately after taking it out, add about 1g of emulsion and brush it with a brush. Test the number of brushings before particles appear or emulsion breaks.

[0063] 1min strength (adhesion): After lamination, the peel strength is tested within 1min, 180°, and the tensile rate is 200mm / min.

[0064] Later strength: After the specimens were prepared, they were cured at 25°C for 24 hours and then the peel strength was tested at 180° and a tensile rate of 200 mm / min.

[0065] Initial heat resistance: After the specimen is prepared, place it at 25°C for 10 minutes, then test it at 180°, 80°C×500g×0.5h, and measure the debonding length within 0.5h.

[0066] Later heat resistance: After the specimen is prepared, it is cured at 25°C for 24 hours, then tested at 180°, 80°C×1000g×0.5h, and the debonding length within 0.5h is measured.

[0067] Example 1

[0068] 133.34 g of dehydrated WHP-104, 80 g of WHP-404, 4.06 g of MPEG1200, 28.34 g of HDI, and 4.16 g of IPDI were added to a nitrogen-treated anhydrous four-necked flask, and then 0.05 g of Bi@8108 and 71.72 g of acetone were added and mixed. The reaction system was gradually heated to 70° C. and the mixture was stirred and reacted until the residual NCO content reached 0.85%, thereby preparing a prepolymer.

[0069] The prepolymer was dissolved in 328.12 g of acetone and cooled to approximately 50° C.; an aqueous solution (24.91 g) containing 4.15 g of sodium N-(2-aminoethyl)-2-aminoethanesulfonate and an acetone solution (10 g) containing 0.18 g of N-(β-aminoethyl)-γ-aminopropyltrimethoxysilane were added to the solvent-diluted prepolymer and vigorously stirred; the mixture was stirred for 20 minutes, and then 306.75 g of dispersion water was added and dispersed with high-speed stirring. After the dispersion was completed, 13.34 g of emulsifier I and an aqueous solution (78.80 g) containing 1.5 g of 2-aminoethanesulfonic acid were added and stirring was continued for more than 20 minutes; and the acetone in the system was removed by distillation to obtain a solvent-free polyurethane-urea dispersion having a solid content of 49 wt % and an average particle size of 174 nm as measured by a Malvern particle size analyzer.

[0070] Example 2

[0071] 290 g of dehydrated WHP-204, 2.05 g of MPEG1200, and 31.49 g of HDI were added to a nitrogen-treated anhydrous four-necked flask, and then 0.04 g of Bi@8108 and 80.89 g of acetone were added and mixed. The reaction system was gradually heated to 80° C. and the mixture was stirred and reacted until the residual NCO content reached 0.86%, thereby preparing a prepolymer.

[0072] The prepolymer was dissolved in 420.60 g of acetone and cooled to approximately 50° C.; an aqueous solution (25.02 g) containing 3.75 g of sodium N-(2-aminoethyl)-2-aminoethanesulfonate and 0.42 g of hydroxyethylethylenediamine was added to the solvent-diluted prepolymer and vigorously stirred; the mixture was stirred for 20 minutes, and then 402.36 g of dispersion water was added and dispersed with high-speed stirring. After the dispersion was completed, 13.82 g of emulsifier II and an aqueous solution (61.48 g) containing 1.43 g of 2-aminoethanesulfonic acid and 0.12 g of sodium N-(2-aminoethyl)-2-aminoethanesulfonate were added, and stirring was continued for more than 20 minutes; and acetone was removed from the system by distillation to obtain a solvent-free polyurethane-urea dispersion having a solid content of 49 wt % and an average particle size of 204 nm as measured by a Malvern particle size analyzer.

[0073] Example 3

[0074] 260 g of dehydrated WHP-204, 23 g of WHP-1556, 3.80 g of MPEG1200, and 34.91 g of HDI were added to a nitrogen-treated anhydrous four-necked flask, and 79.57 g of acetone was added and mixed. The reaction system was gradually heated to 75° C. and the mixture was stirred and reacted until the residual NCO content reached 0.86%, thereby preparing a prepolymer.

[0075] The prepolymer was dissolved in 445.61 g of acetone and cooled to approximately 50° C.; an aqueous solution (35.52 g) containing 3.95 g of sodium N-(2-aminoethyl)-2-aminoethanesulfonate and 0.49 g of isophorone diamine was added to the solvent-diluted prepolymer and vigorously stirred; the mixture was stirred for 20 minutes, and then 394.41 g of dispersing water was added and dispersed with high-speed stirring. After the dispersion was completed, 12.70 g of emulsifier III and an aqueous solution (55.80 g) containing 1.20 g of sodium 2-aminoethanesulfonate were added, and stirring was continued for more than 20 minutes; and the acetone in the system was removed by distillation to obtain a solvent-free polyurethane-urea dispersion having a solid content of 49 wt % and an average particle size of 182 nm as measured by a Malvern particle size analyzer.

[0076] Example 4

[0077] 280 g of dehydrated WHP-204, 7.0 g of MPEG2000, and 29.2 g of HDI were added to a nitrogen-treated anhydrous four-necked flask, and then 0.08 g of Bi@8108 and 126.48 g of acetone were added and mixed. The reaction system was gradually heated to 75° C. and the mixture was stirred and reacted until the residual NCO content reached 0.61%, thereby preparing a prepolymer.

[0078] The prepolymer was dissolved in 505.92 g of acetone and cooled to approximately 50° C.; an aqueous solution (25.2 g) containing 4.20 g of sodium N-(2-aminoethyl)-2-aminoethanesulfonate and an acetone solution (20 g) containing 0.30 g of N-(β-aminoethyl)-γ-aminopropyltrimethoxysilane were added to the solvent-diluted prepolymer and vigorously stirred; the mixture was stirred for 20 minutes, and then 392.81 g of dispersion water was added and dispersed with high-speed stirring. After the dispersion was completed, 19.0 g of emulsifier I and an aqueous solution (99.50 g) containing 0.90 g of sodium 2-aminoethanesulfonate were added and stirring was continued for more than 20 minutes; and the acetone in the system was removed by distillation to obtain a solvent-free polyurethane-urea dispersion having a solid content of 49 wt % and an average particle size of 192 nm as measured by a Malvern particle size analyzer.

[0079] Comparative Example 1 (without S6 component)

[0080] 133.34 g of dehydrated WHP-104, 80 g of WHP-404, 4.06 g of MPEG1200, 28.34 g of HDI, and 4.16 g of IPDI were added to a nitrogen-treated anhydrous four-necked flask, and then 0.05 g of Bi@8108 and 71.72 g of acetone were added and mixed. The reaction system was gradually heated to 70° C. and the mixture was stirred and reacted until the residual NCO content reached 0.85%, thereby preparing a prepolymer.

[0081] The prepolymer was dissolved in 328.12 g of acetone and cooled to approximately 50° C.; an aqueous solution (24.91 g) containing 4.15 g of sodium N-(2-aminoethyl)-2-aminoethanesulfonate and an acetone solution (10 g) containing 0.18 g of N-(β-aminoethyl)-γ-aminopropyltrimethoxysilane were added to the solvent-diluted prepolymer and vigorously stirred; the mixture was stirred for 20 minutes, and then 306.75 g of dispersing water was added and dispersed with high-speed stirring. After the dispersion was completed, an aqueous solution (78.80 g) containing 13.34 g of emulsifier I was added and stirring was continued for more than 20 minutes; and the acetone in the system was removed by distillation to obtain a solvent-free polyurethane-urea dispersion having a solid content of 49 wt % and an average particle size of 178 nm as measured by a Malvern particle size analyzer.

[0082] Comparative Example 2 (without S7 component)

[0083] 133.34 g of dehydrated WHP-104, 80 g of WHP-404, 4.06 g of MPEG1200, 28.34 g of HDI, and 4.16 g of IPDI were added to a nitrogen-treated anhydrous four-necked flask, and then 0.05 g of Bi@8108 and 71.72 g of acetone were added and mixed. The reaction system was gradually heated to 70° C. and the mixture was stirred and reacted until the residual NCO content reached 0.85%, thereby preparing a prepolymer.

[0084] The prepolymer was dissolved in 328.12 g of acetone and cooled to approximately 50° C.; an aqueous solution (24.91 g) containing 4.15 g of sodium N-(2-aminoethyl)-2-aminoethanesulfonate and an acetone solution (10 g) containing 0.18 g of N-(β-aminoethyl)-γ-aminopropyltrimethoxysilane were added to the solvent-diluted prepolymer and vigorously stirred; the mixture was stirred for 20 minutes, and then 306.75 g of dispersion water was added and dispersed with high-speed stirring. After the dispersion was completed, an aqueous solution (78.80 g) containing 1.5 g of 2-aminoethanesulfonic acid was added and stirring was continued for more than 20 minutes; and the acetone in the system was removed by distillation to obtain a solvent-free polyurethane-urea dispersion having a solid content of 49 wt % and an average particle size of 182 nm as measured by a Malvern particle size analyzer.

[0085] Comparative Example 3 (S7 component EO is low)

[0086] 133.34 g of dehydrated WHP-104, 80 g of WHP-404, 4.06 g of MPEG1200, 28.34 g of HDI, and 4.16 g of IPDI were added to a nitrogen-treated anhydrous four-necked flask, and then 0.05 g of Bi@8108 and 71.72 g of acetone were added and mixed. The reaction system was gradually heated to 70° C. and the mixture was stirred and reacted until the residual NCO content reached 0.85%, thereby preparing a prepolymer.

[0087] The prepolymer was dissolved in 328.12 g of acetone and cooled to approximately 50° C. An aqueous solution (24.91 g) containing 4.15 g of sodium N-(2-aminoethyl)-2-aminoethanesulfonate and an acetone solution (10 g) containing 0.18 g of N-(β-aminoethyl)-γ-aminopropyltrimethoxysilane were added to the solvent-diluted prepolymer and vigorously stirred. The mixture was stirred for 20 minutes, and then 306.75 g of dispersing water was added and dispersed with high-speed stirring. After the dispersion was completed, 13.34 g of emulsifier IV and an aqueous solution (78.80 g) containing 1.5 g of sodium N-(2-aminoethyl)-2-aminoethanesulfonate were added and stirring was continued for more than 20 minutes. The acetone in the system was removed by distillation to obtain a solvent-free polyurethane-urea dispersion having a solid content of 49 wt % and an average particle size of 177 nm as measured by a Malvern particle size analyzer.

[0088] Preparation of adhesive:

[0089] Take 100 g of each of the emulsions of Examples 1-4 and Comparative Examples 1-3, put them in a steel cup, mark it, add 0.2% wetting agent, 0.05% defoaming agent, 0.3% thickener, and 5% isocyanate curing agent based on the mass of the emulsion, stir well and set aside.

[0090] The test results are shown in Table 1:

[0091]

[0092] As shown in the table above, the aqueous polyurethane-urea dispersions prepared in Examples 1-4 of the present invention, when used in combination with an aqueous rubber treatment agent, exhibit significantly better brushability than those in Comparative Examples 1-3, while maintaining substantially unchanged peel strength and heat resistance. Therefore, this technical solution possesses significant practical application value.

Claims

1. A highly paintable aqueous polyurethane-urea dispersion, characterized in that: Prepared from raw materials including the following components: S1, polyisocyanate; S2, polymer polyol, having an average molecular weight of 800-4000 g / mol; S3, a nonionic hydrophilic compound that can react with isocyanate; S4. Hydrophilic or potentially hydrophilic compounds containing 1 to 3 NCO reactive groups, of which the amount of difunctional compounds shall not be less than 90%; S5, a small molecule compound containing amino or hydroxyl groups with a functionality of 1 to 3, having an average molecular weight of 60-499 g / mol; S6. Hydrophilic or hydrophilic potential amino compounds containing 1 to 2 functional groups, of which monofunctional compounds account for not less than 80%; S7, fatty alcohol polyoxyethylene ether, cloud point greater than 70 ° C, its general formula is RO (CH2CH2O) n H, R is saturated or unsaturated C 10 ~C 16 Hydrocarbyl, n=20-60; S8, water; S9, an optional catalyst capable of catalyzing the reaction of isocyanate groups with hydroxyl groups; S10. An organic solvent containing no group capable of reacting with isocyanate.

2. The aqueous polyurethane-urea dispersion according to claim 1, characterized in that Based on the total mass of components S1-S7: The amount of component S1 is 7.5 to 16.5 wt%, preferably 9 to 14 wt%; The amount of component S2 is 72-90 wt%, preferably 79-85 wt%; The amount of component S3 is 0.1 to 2.1 wt%, preferably 0.5 to 1.7 wt%; The amount of component S4 is 0.5 to 2.3 wt%, preferably 1.0 to 1.8 wt%; The amount of component S5 is 0.01 to 1.0 wt%, preferably 0.03 to 0.5 wt%; The amount of component S6 is 0.2-1.2 wt%, preferably 0.4-0.9 wt%. The amount of component S7 is 1.0-6.0 wt%, preferably 1.4-5 wt%.

3. The aqueous polyurethane-urea dispersion according to claim 1 or 2, characterized in that The polyisocyanate of component S1 is selected from one or more of hexamethylene diisocyanate, isophorone diisocyanate, 4,4-dicyclohexylmethane diisocyanate, 2,4-toluene diisocyanate, 2,6-toluene diisocyanate, pentamethylene diisocyanate, tetramethylene diisocyanate, dodecamethylene diisocyanate, 1,4-cyclohexane diisocyanate, 2,2-diphenylmethane diisocyanate, 4,4-diphenylmethane diisocyanate, 2,4-diphenylmethane diisocyanate, tetramethylxylyl diisocyanate and p-xylylenediisocyanate, preferably one or more of hexamethylene diisocyanate and isophorone diisocyanate; and / or The component S2 is selected from one or more polymer diols having a number average molecular weight of 800-4000, preferably one or more linear or branched polyester polyols and polycarbonate polyols, more preferably polyester diols prepared by reacting one or more of 1,4-butanediol, 1,5-pentanediol, 1,6-hexanediol, neopentyl glycol, and diethylene glycol with adipic acid; and / or The nonionic hydrophilic compound of component S3 is a monofunctional polyoxyethylene ether with a number average molecular weight of 200-8000 and an ethylene oxide number of 4-200, preferably polyethylene glycol monomethyl ether with a number average molecular weight of 500-3000 and an ethylene oxide number of 12-75.

4. The aqueous polyurethane-urea dispersion according to any one of claims 1 to 3, characterized in that The component S4 is selected from a hydrophilic compound containing an ionic group and 1-3 NCO reactive functional groups and / or a hydrophilic compound containing a potential ionic group and 1-3 NCO reactive functional groups; preferably, the NCO reactive group is an amino group or a hydroxyl group, the ionic group is a sulfonate and / or a carboxylate, and the potential ionic group is a sulfonic acid group and / or a carboxylic acid group; more preferably, the component S4 is selected from one or more of dihydroxycarboxylic acids and salts thereof, dihydroxysulfonic acids and salts thereof, diaminocarboxylic acids and salts thereof, and diaminosulfonic acids and salts thereof; further preferably, the component S4 is selected from one or more of dihydroxymethylpropionic acid and alkali metal salts and / or ammonium salts thereof, N-(2-aminoethyl)-2-aminoethanesulfonic acid and alkali metal salts and / or ammonium salts thereof, N-(2-aminoethyl)-2-aminobutanesulfonic acid and alkali metal salts and / or ammonium salts thereof, and N-(2-aminoethyl)-3-aminopropanesulfonic acid and alkali metal salts and / or ammonium salts thereof; and / or The component S5 is an aliphatic small molecule compound with a functionality of 1-3 containing a primary or secondary amino group; preferably one or more of isophoronediamine, 1,6-hexamethylenediamine, 4,4'-diaminodicyclohexylmethane, N-(2-hydroxyethyl)ethylenediamine, N-(β-aminoethyl)-γ-aminopropyltrimethoxysilane, ethanolamine and diethanolamine; and / or The component S6 is selected from a hydrophilic compound containing an ionic group and 1-2 NCO reactive functional groups and / or a hydrophilic compound containing a potential ionic group and 1-2 NCO reactive functional groups; preferably, the NCO reactive group is an amino group or a hydroxyl group, the ionic group is a sulfonate and / or a carboxylate, and the potential ionic group is a sulfonic acid group and / or a carboxylic acid group; more preferably, the component S6 is selected from aminocaproic acid and its alkali metal salt and / or ammonium salt, taurine and its alkali metal salt and / or ammonium salt.

5. The aqueous polyurethane-urea dispersion according to any one of claims 1 to 4, characterized in that The component S7 is fatty alcohol polyoxyethylene ether, the cloud point is greater than 70 ° C, and its general formula is RO (CH2CH2O) n H, R is saturated or unsaturated C 12 ~C 15 A hydrocarbon group, wherein n is 20 to 40.

6. The aqueous polyurethane-urea dispersion according to any one of claims 1 to 5, characterized in that The solid content of the aqueous polyurethane-urea dispersion is 30-65 wt %, preferably 40-55 wt %; the pH value of the aqueous polyurethane-urea dispersion is 6-9, preferably 6.5-8.

7. A method for preparing the aqueous polyurethane-urea dispersion according to any one of claims 1 to 6, characterized in that: The steps include: (1) Component S1, component S2, component S3, component S8 and part of component S9 are mixed and reacted at 65-85° C. until the NCO content reaches the theoretical value to form a diisocyanate-terminated prepolymer; (2) The prepolymer obtained in step 1) is cooled to 25-55° C., and the remaining component S9 is added and stirred to mix uniformly; then, components S4 and S5 are added to react with the prepolymer. After the reaction is completed, water is added for dispersion, and then components S6 and S7 are added and mixed thoroughly to obtain an aqueous polyurethane-urea dispersion.

8. The preparation method according to claim 7, characterized in that The mass ratio of the partial component S9 in step (1) to the remaining component S9 in step 2) is 1 / (6-15).

9. The preparation method according to claim 7, characterized in that In step 2), the components S4 and S5 are added in the form of aqueous solution or acetone solution, and the amount of water or acetone used is 1-20 times the total mass of the components S4 and S5.

10. Use of the aqueous polyurethane-urea dispersion according to any one of claims 1 to 6 or the aqueous polyurethane-urea dispersion prepared by the method according to any one of claims 7 to 9 in an adhesive.

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