Waterborne polyurethane-polyurea dispersion as well as preparation method and application thereof

Abstract

The invention provides a waterborne polyurethane-polyurea dispersion as well as a preparation method and application thereof. According to the invention, a trace amount of allophanate and ether bonds are matched in polyurethane, so that the initial heat resistance, humidity and heat resistance and other properties of the product are greatly improved while the initial viscosity of polyurethane-urea is not influenced. The waterborne polyurethane-polyurea dispersion can be applied to the fields of adhesives and the like.

Description

Technical Field

[0001] The invention belongs to the technical field of polyurethane dispersions, and in particular relates to an aqueous polyurethane-polyurea dispersion and a preparation method and application thereof. Background Art

[0002] As environmental protection becomes increasingly stringent, oil-to-water conversion has become a trend in the fields of coatings and adhesives. Polyurethane or polyurethane-urea aqueous dispersions use only water as a dispersion medium. They are non-polluting to the environment during use, non-flammable, non-explosive, safe and reliable, and are widely used in the fields of coatings and adhesives. However, there is currently a huge gap between water-based adhesives and oil-based adhesives in terms of initial adhesion and resistance, which has greatly hindered the process of oil-to-water conversion in the adhesive field. How to prepare water-based adhesive products with equivalent performance to oil-based adhesives is undoubtedly a huge challenge for water-based adhesive developers.

[0003] At present, the industry usually improves initial viscosity by adding end capping or reducing the urea content, but this will seriously affect the initial resistance of the product. Patents CN101848952B and CN101848954B prepare water-based polyurethane adhesives by controlling the average amino functionality, which have a lower activation temperature, but the introduction of a monofunctional end capping agent greatly reduces the initial heat resistance of the product. Patent CN106432663A introduces a urea-free polyurethane dispersion. The water-based polyurethane produced by this patent contains almost no urea bonds, and the resistance is greatly reduced.

[0004] Aqueous polyurethane contains a large number of hydrophilic groups. In order to obtain the same resistance as oily glue, more crosslinking must be introduced, but the introduction of crosslinking usually leads to a decrease in viscosity or other disadvantages. Patent CN102216359 obtains an aqueous dispersion of polyurethane or polyurethane urea containing carboxyl groups at the end by introducing monoamino and / or monohydroxy carboxylic acids in the reaction system. The terminal carboxyl group has high activity and can be matched with carbodiimide to produce a rapid crosslinking reaction, thereby significantly improving the performance of the adhesive film. However, carboxylic acid can cause the hydrolysis of ester bonds in polyurethane, and the stability of carbodiimide itself is not good, which is not conducive to the storage of the product and cannot be used normally. Patent CN108250390B improves the resistance of the product by introducing non-sterically hindered siloxane groups in the side chains of polyurethane or polyurethane-urea. During the drying and activation process of the aqueous dispersion, the siloxanes on the side chains are hydrolyzed and crosslinked with each other, increasing the crosslinking density, and significantly improving the heat resistance, moisture and heat resistance and other properties of the adhesive obtained therefrom, but the introduction of the crosslinking also reduces the initial viscosity of the product.

[0005] In the process of preparing polyurethane adhesives, people generally believe that the content of allophanate will affect the initial viscosity of the product, so it is hoped that the content of allophanate in the product is as low as possible. Patent CN102405243 reduces the content of allophanate / biuret and controls the molecular weight distribution to obtain a polyurethane resin dispersion with excellent film-forming properties, but the reduction of micro-crosslinking leads to a lack of heat resistance of the product.

[0006] In summary, the current water-based polyurethane adhesive still has the problem of difficult balance between initial adhesion and durability, which needs to be solved urgently. Summary of the invention

[0007] One of the purposes of the present invention is to provide an aqueous polyurethane-polyurea dispersion applicable to the adhesive field, in view of the problem that the initial viscosity and heat resistance and moisture-heat resistance of the existing aqueous polyurethane-urea are difficult to balance.

[0008] The inventors found that by introducing a trace amount of allophanate into polyurethane and combining it with a certain amount of ether bonds to weaken the hydrogen bonding between urea bonds, the heat resistance and moisture-heat resistance of the product can be greatly improved without affecting the initial viscosity of the polyurethane-urea.

[0009] In order to achieve one aspect of the above purpose, the present invention adopts the following technical solution:

[0010] A polyurethane or polyurethane-urea aqueous dispersion, the reaction product obtained by reacting a composition comprising the following components:

[0011] a) at least one polyol component having a functionality of 2 to 4;

[0012] b) at least one polyisocyanate component;

[0013] c) at least one hydrophilic compound component, wherein the hydrophilic group of the hydrophilic compound comprises one or both of an ionic group and a potential ionic group, and the hydrophilic compound contains 2 to 3 isocyanate-reactive groups; the ionic group is preferably a carboxylate and / or a sulfonate group; the potential ionic group is preferably a carboxyl group and / or a sulfonic acid group; the isocyanate-reactive group is preferably a hydroxyl group and / or an amino group;

[0014] d) an optional component of an isocyanate-reactive nonionic hydrophilic compound;

[0015] e) optional small molecule alcohol chain extender;

[0016] f) optionally, a compound containing 1 to 3 amino groups and / or hydroxyl groups in the molecule; and

[0017] The ether bond content in the reaction product is 20 μmol / g to 2000 μmol / g based on the mass of the reaction product, preferably 50 μmol / g to 1000 μmol / g, and more preferably 100 μmol / g to 700 μmol / g; and the allophanate content in the reaction product is 1 μmol / g to 30 μmol / g based on the mass of the reaction product, preferably 2 μmol / g to 10 μmol / g;

[0018] The allophanate content is obtained by controlling the residual NCO content after the reaction to be 0.01 wt% to 0.13 wt% lower than the theoretical value, or by extending the reaction time by more than 50% after the NCO content reaches the theoretical value and keeping the NCO constant. The NCO theoretical value is calculated from the hydroxyl value and water content of the raw materials;

[0019] The component a) is a diol and / or polyol having a number average molecular weight of 400 to 10,000; preferably a diol and / or polyol having a number average molecular weight of 1000 to 5000; more preferably one or more of polyester, polycarbonate, polylactone polyol, polyether polyol and polyurethane polyol having a number average molecular weight of 1000 to 3000 and a functionality of 2 to 3.

[0020] Suitable polyester polyols may be linear polyester diols and / or slightly branched polyester diols (a small amount of polyester polyols with a functionality greater than 3 may be contained in the slightly branched polyester diols). The polyester polyols can be obtained, for example, by known means from carboxylic acids and / or acid anhydrides such as aliphatic, alicyclic, aromatic dicarboxylic acids or polycarboxylic acids or their corresponding acid anhydrides, etc., and polyols through dehydration condensation. Examples of the carboxylic acids or acid anhydrides for dehydration condensation include, but are not limited to, succinic acid, methylsuccinic acid, malonic acid, succinic acid, glutaric acid, adipic acid, pimelic acid, suberic acid, azelaic acid, sebacic acid, terephthalic acid, isophthalic acid, phthalic acid, tetrahydrophthalic acid, hexahydrophthalic acid, cyclohexanedicarboxylic acid, maleic acid, fumaric acid, trimellitic acid, phthalic anhydride, trimellitic anhydride, succinic anhydride or mixtures thereof; the polyols for dehydration condensation are preferably low molecular weight polyols (for example, polyols with a molecular weight not greater than 400), and examples thereof include, but are not limited to, ethylene glycol, diethylene glycol, triethylene glycol, tetraethylene glycol, 1,2 - propanediol, dipropylene glycol, tripropylene glycol, tetrapropylene glycol, 1,3 - propanediol, 1,4 - butanediol, 1,3 - butanediol, 2,3 - butanediol, 1,5 - pentanediol, 1,6 - hexanediol, 2,2 - dimethyl - 1,3 - propanediol, 1,4 - dihydroxycyclohexane, 1,4 - bis(hydroxymethyl)cyclohexane, 1,8 - octanediol, 1,10 - decanediol, 1,12 - dodecanediol or mixtures of several of them. Optionally, polyols with a higher functionality, such as trimethylolpropane, glycerol or pentaerythritol, may also be added during the above - mentioned dehydration condensation. Alicyclic and aromatic polyhydroxy compounds are also suitable as the polyols for preparing the polyester polyols.

[0021] Preferably, the carboxylic acid or acid anhydride for dehydration condensation is one or more of phthalic acid, isophthalic acid, terephthalic acid and adipic acid, more preferably adipic acid, and the polyol for dehydration condensation is preferably one or more of ethylene glycol, 1,4 - butanediol, 1,6 - hexanediol and neopentyl glycol, more preferably 1,4 - butanediol.

[0022] The polyester polyol may also be a homopolymer or copolymer of lactones, which can be obtained by ring - opening reaction of lactones or a mixture of lactones with suitable di - and / or higher functionality low molecular weight polyols. Among them, the lactones are preferably butyrolactone, ε - caprolactone, methyl - ε - caprolactone and mixtures thereof, and the polyols can be the low molecular weight polyols as the structural components of the polyester polyols as described above. A linear polyester polyol obtained by ring - opening ε - caprolactone with 1,4 - butanediol, 1,6 - hexanediol, 2,2 - dimethyl - 1,3 - propanediol or mixtures thereof is preferably used.

[0023] Component a) can also be a polycarbonate polyol with hydroxyl groups prepared using a diol and a carbonate, wherein the diol can be 1,4-butanediol or 1,6-hexanediol, and the carbonate can be a diaryl carbonate or a dialkyl carbonate. The diaryl carbonate includes diphenyl carbonate, and the dialkyl carbonate includes dimethyl carbonate; preferably, the polycarbonate polyol is a polycarbonate polyol prepared by reacting 1,6-hexanediol with dimethyl carbonate.

[0024] The polyether polyol is selected from one or more of polypropylene oxide polyols, polytetrahydrofuran polyols, and their copolymer polyols.

[0025] Component b) the polyisocyanate is an organic compound having at least two isocyanate groups, preferably a diisocyanate, more preferably one or more of tetramethylene diisocyanate, pentamethylene diisocyanate, hexamethylene diisocyanate, dodecamethylene diisocyanate, 1,4-cyclohexane diisocyanate, isophorone diisocyanate, 4,4'-dicyclohexylmethane diisocyanate, 4,4'-dicyclopropylpropane diisocyanate, 1,4-phenylene diisocyanate, 2,4-toluene diisocyanate, 2,6-toluene diisocyanate, 4,4'-diphenylmethane diisocyanate, 2,2'- and 2,4'-diphenylmethane diisocyanate, tetramethylxylene diisocyanate, and p-phenylene dimethyl diisocyanate, and further preferably one or more of hexamethylene diisocyanate, isophorone diisocyanate, and 4,4'-dicyclohexylmethane diisocyanate.

[0026] Component b) may also include a small amount, preferably not exceeding 10 wt% of the total amount of component c), of polyisocyanates having a functionality of more than 3 isocyanate groups per molecule known in the art, such as polyisocyanates prepared by modifying simple aliphatic, cycloaliphatic, araliphatic, and / or aromatic diisocyanates or modified polyisocyanates synthesized from at least two diisocyanates (such as having uretdione, isocyanurate, carbamate, urethane, biuret, carbodiimide, iminooxadiazinedione, and / or oxadiazinetrione structures).

[0027] In the present invention, the latent ionic group in component c) refers to a covalent bond functional group that can be easily converted into a corresponding salt with the change of the solution pH by adding a neutralizing agent. Preferred latent ionic groups include acid groups, and the acid groups are carboxyl groups (-COOH) and / or sulfonic acid groups (-SO3H); preferred NCO-reactive groups are hydroxyl groups and / or amino groups.

[0028] Preferred ionic groups are carboxylate (-COO - ) and / or sulfonate (-SO3 - ).

[0029] Preferably, examples of component c) include, but are not limited to, one or more of dihydroxycarboxylic acids, trihydroxycarboxylic acids, dihydroxy sulfonic acids, trihydroxy sulfonic acids, diamino sulfonic acids, triamino sulfonic acids, diamino carboxylic acids, triamino carboxylic acids, polyether sulfonic acids, and their salts (alkali metal salts, alkaline earth metal salts, and / or ammonium salts), etc.

[0030] Particularly preferably, component c) is one or more of those composed of dimethylolacetic acid, dimethylolpropionic acid, dimethylolbutyric acid, dihydroxysuccinic acid, N-(2-aminoethyl)-2-aminoethanesulfonic acid, N-(3-aminopropyl)-2-aminoethanesulfonic acid, N-(3-aminopropyl)-3-aminopropanesulfonic acid, N-(2-aminoethyl)-3-aminopropanesulfonic acid, poly(propylene oxide) modified sulfonic acid, and their salts, and / or one or more of Michael addition products formed by adding one or more of these acids such as acrylic acid, methacrylic acid, maleic acid, and fumaric acid to amines (such as ethylenediamine, butanediamine, isophoronediamine, and / or 1,6-hexanediamine).

[0031] If component c) contains latent ionic groups, preferably, a neutralizing agent can be added to the composition before, during, after, or stepwise addition of component c). The amount of the neutralizing agent added is such that the latent ionic groups are partially or completely converted into ionic groups. The neutralizing agent is selected from one or more of primary amines, secondary amines, tertiary amines, alkali metal compounds, and alkaline earth metal compounds. Preferred neutralizing agents are one or more of triethanolamine, dimethylethanolamine, N-methylmorpholine, dimethylisopropylamine, N-methyldiethanolamine, triethylamine, dimethylcyclohexylamine, ethyldiisopropylamine, sodium hydroxide, potassium hydroxide, lithium hydroxide, and calcium hydroxide, etc.

[0032] Generally, the amount of the neutralizing agent added is such that, based on the total molar amount of the acid groups introduced, the degree of neutralization is at least 50%, preferably at least 70%, and not more than 130%. Those skilled in the art understand that in the system, in addition to the acid groups being neutralized to form ionic groups, there are also free neutralizing agents. Particularly preferably, the degree of neutralization is 90 - 110%. Wherein, the degree of neutralization = the molar amount of the neutralizing agent added / the total molar amount of the acid groups introduced.

[0033] More preferably, component c) is N-(2-aminoethyl)-2-aminoethanesulfonate, dimethylolpropionate, and / or poly(propylene oxide) modified sulfonate.

[0034] The polyether sulfonate polyol described above can be prepared by the method reported in the patent CN200580023287.

[0035] Component d) of the present invention is selected from polyoxyethylene ethers and / or polyoxyethylene polyoxypropylene copolymers containing at least one hydroxyl group and / or amino group; preferably polyoxyethylene ethers and / or polyoxyethylene polyoxypropylene copolymers containing only one hydroxyl group, more preferably polyoxyethylene ethers containing only one hydroxyl group; examples of the initiators for preparing the polyoxyethylene ethers and / or polyoxyethylene polyoxypropylene copolymers containing only one hydroxyl group include but are not limited to saturated monohydric alcohols, unsaturated alcohols, aromatic alcohols, araliphatic alcohols, secondary monamines and heterocyclic secondary amines. Among them, the saturated monohydric alcohol can be one or more of methanol, ethanol, n-propanol, isopropanol, n-butanol, isobutanol, sec-butanol, isomeric pentanols, hexanol, heptanol, octanol, nonanol, n-decanol, n-dodecanol, n-tetradecanol, n-hexadecanol, cyclohexanol, hydroxymethylcyclohexane or 3-ethyl-3-hydroxymethyloxolane; the unsaturated alcohol can be one or more of allyl alcohol, 1,1-dimethyl-allyl alcohol or oleyl alcohol; the aromatic alcohol can be one or more of phenol, isomeric cresols or hydroxymethylphenol; the araliphatic alcohol can be one or more of benzyl alcohol, anisyl alcohol or cinnamyl alcohol; the secondary monamine can be one or more of dimethylamine, diethylamine, dipropylamine, diisopropylamine, di-n-butylamine, diisobutylamine, bis(2-ethylhexyl)-amine, N-methylcyclohexylamine, N-ethylcyclohexylamine; the heterocyclic secondary amine can be one or two of morpholine and pyrrolidone; the preferred initiator is a saturated monohydric alcohol having at most 4 carbon atoms, and methanol is particularly preferably used as the initiator. Preferably, the number of ethylene oxide units in each molecule of the polyoxyethylene ether is 4 to 200, preferably 12 to 75;

[0036] Preferably, the polyoxyethylene ether is a polyoxyethylene ether having a number average molecular weight of 200 to 8000 and 4 to 200 ethylene oxide units, preferably poly(ethylene glycol) monomethyl ether having a number average molecular weight of 500 to 3500 and 12 to 75 ethylene oxide units. The optional small molecule alcohol chain extender e having a molecular weight of 60 to 400 has a functionality of 2 to 4. Examples of suitable small molecule alcohols include but are not limited to ethylene glycol, diethylene glycol, triethylene glycol, tetraethylene glycol, 1,2-propanediol, dipropylene glycol, tripropylene glycol, tetrapropylene glycol, 1,3-propanediol, 1,4-butanediol, 1,3-butanediol, 2,3-butanediol, 1,5-pentanediol, 1,6-hexanediol, 2,2-dimethyl-1,3-propanediol, 1,4-dihydroxycyclohexane, 1,4-bis(hydroxymethyl)cyclohexane, 1,8-octanediol, 1,10-decanediol, 1,12-dodecanediol, trimethylolpropane, glycerol, pentaerythritol or a mixture of several of them.

[0037] Component f) in the present invention is a compound containing 1 to 3, preferably 2 to 3 NCO-reactive functional groups, and the NCO-reactive functional groups can be one or more of hydroxyl groups, primary amino groups, and secondary amino groups. Preferably, at least one NCO-reactive functional group in component f) is a primary amino group or a secondary amino group. Component f) can be an aliphatic or cycloaliphatic primary monoamine or secondary monoamine, such as ethylamine, diethylamine, isopropylamine, diisopropylamine, butylamine, or cyclohexylamine. It can also be an amino alcohol containing both an amino group and a hydroxyl group, such as ethanolamine, diethanolamine, N-methylethanolamine, diisopropanolamine, 1,3-diamino-2-propanol, N-(2-hydroxyethyl)ethylenediamine, N,N-bis(2-hydroxyethyl)ethylenediamine, and 2-propanolamine. It can also be diamines and triamines, such as ethylenediamine, 1,3-propanediamine, 1,4-butanediamine, 1,5-pentanediamine, 1,6-hexanediamine, 1,7-heptanediamine, 1,8-octanediamine, 1,9-nonanediamine, 1,10-decanediamine, 4,4'-diaminodicyclohexylmethane, N,N'-dimethyl-1,3-propanediamine, N-benzylethylenediamine, N,N'-diphenylethylenediamine, N-methylethylenediamine, m-phenylenediamine, 1,3-cyclohexanediamine, N,N'-dimethylethylenediamine, isophoronediamine, piperazine, 1,4-diaminocyclohexane, and diethylenetriamine. It can also be special amines, such as adipic dihydrazide and hydrazine. Mixtures of two or more of the above compounds can also be used. More preferably, component f) is ethylenediamine, isophoronediamine, and / or N-(2-hydroxyethyl)ethylenediamine.

[0038] In the present invention, the aqueous polyurethane-polyurea dispersion preferably has a solid content of 15 to 60 wt%, more preferably 35 to 55 wt%; the pH value of the dispersion is preferably 4 to 11, more preferably 5 to 9; the average particle size of the solid phase particles in the system is preferably 20 to 1000 nm, more preferably 50 to 300 nm.

[0039] The present invention also provides a method for preparing the above-mentioned aqueous dispersion of polyurethane or polyurethane-urea, reacting components a), b), c), d) and optionally e) in one or more steps to form a prepolymer with terminal isocyanate groups, and then reacting the prepolymer with optionally f) in one or two stages, and then dispersing or dissolving with water, wherein a solvent that can be partially or completely removed by distillation during or after dispersion is optionally used; or,

[0040] Reacting components a), b), d) and optionally e) in one or more steps to form a prepolymer with terminal isocyanate groups, and then reacting the prepolymer with components c) and optionally f) in one or more stages, and then dispersing or dissolving with water, wherein a solvent that can be partially or completely removed by distillation during or after dispersion is optionally used.

[0041] The preparation of the aqueous dispersion of the polyurethane or polyurethane-urea according to the invention can be carried out in one or more steps in the homogeneous phase or, in the case of a multi-step reaction, part of the reaction is carried out in the dispersed phase. The complete or partial polymerization reaction is followed by a dispersion, emulsification or dissolution step. Optionally, the dispersed phase can then be subjected to a further step of addition polymerization or modification.

[0042] All methods known from the prior art, such as emulsifier shear dispersion, acetone method, prepolymer mixing method, melt emulsification method, ketimine method and solid spontaneous dispersion method or their derivative methods can be used for the preparation of the above-mentioned aqueous dispersion of polyurethane or polyurethane-urea. An overview of these methods can be found in Methoden der organischen Chemie (Houben-Weyl, Erweiterungs-und zur 4.Auflage, volume E20, H.Bartl and J.Falbe, Stuttgart, New York, Thieme 1987, pages 1671-1682); melt emulsification method, prepolymer mixing method and acetone method are preferred; acetone method is particularly preferred.

[0043] Suitable solvents may be acetone, butanone, tetrahydrofuran, methyl isobutyl ketone, dioxane, acetonitrile, dipropylene glycol dimethyl ether, N-methyl pyrrolidone, N-ethyl pyrrolidone, N-butyl pyrrolidone, etc., which may be added in batches or all at any stage at the beginning of the reaction, during the reaction, or after the reaction. Acetone and butanone are preferred, and acetone is more preferred.

[0044] The ratio of the molar amount of isocyanate groups to the sum of the molar amounts of hydroxyl groups and amino groups used to prepare the aqueous polyurethane or polyurethane-urea dispersion of the invention is 0.6-2.5:1, preferably 1.0-1.85:1.

[0045] The conversion is usually monitored by following the NCO content of the reaction mixture. For this purpose, spectroscopic measurements (e.g. infrared or near infrared spectroscopy, determination of the refractive index) and chemical potentiometric titration (e.g. chemical titration by taking a sample) can be performed, preferably chemical potentiometric titration.

[0046] In the preparation, the catalyst can be used in batches or all at any stage at the beginning of the reaction, during the reaction or after the reaction. The catalyst used can be a catalyst known to those skilled in the art for accelerating the reaction of NCO and OH, such as triethylamine, 1,4-diazabicyclo-[2,2,2]-octane, dibutyltin dilaurate, tin isooctanoate, zinc isooctanoate, bismuth isooctanoate, zinc neodecanoate and bismuth neodecanoate, etc. Bismuth neodecanoate, bismuth isooctanoate and zinc isooctanoate are preferred, and bismuth neodecanoate is more preferred.

[0047] The chain extension reaction is usually carried out at a temperature of 10 to 100°C, preferably 25 to 60°C.

[0048] The organic solvent optionally used, for example acetone, is distilled off during and / or after the dispersion.

[0049] The aqueous polyurethane-polyurea dispersion prepared according to the present invention can be used alone or together with auxiliary substances and additives known in the coating and adhesive technology, such as emulsifiers, light stabilizers (such as UV absorbers and sterically hindered amines (HALS)), antioxidants, fillers, anti-settling agents, defoamers and / or wetting agents, flow regulators, reactive diluents, plasticizers, neutralizers, catalysts, auxiliary solvents, thickeners, pigments, dyes, matting agents, tackifiers, etc. Additives and / or auxiliary agents can be added before / after polymerization or after dispersion.

[0050] The aqueous polyurethane-polyurea dispersions prepared according to the invention can also be used in combination with other aqueous or solvent-containing oligomers or polymers, for example, polyolefins, polyvinyl alcohols, polyvinyl esters, polyvinyl ethers, polyvinyl chloride, polystyrene, polybutadiene, polyurethanes, polyurethane-polyureas, polyurethane-polyacrylates, polyesters, polyacrylates and / or copolymer dispersions or emulsions or aqueous or organic solutions. The compatibility of such mixtures must be tested in each case using simple preliminary tests.

[0051] The aqueous polyurethane-polyurea dispersion prepared according to the invention and the adhesive or binder combination based thereon are suitable for bonding any substrate, such as all types of metals, alloys, wood, wood-based materials, particleboard, ceramics, stone, concrete, asphalt, hard fiber, glass, glass fiber, carbon fiber, carbon nanotubes, leather, textiles and other inorganic materials. They are also suitable for bonding rubber materials such as natural and synthetic rubber, various plastics such as polyurethane, polyvinyl acetate, polyvinyl chloride, ABS (acrylic-butadiene-styrene), PC (polycarbonate), polyolefin plastics and mixtures thereof.

[0052] Based on the aqueous dispersion of the present invention, coating agents, adhesives and / or sealants can be prepared by known techniques in adhesive technology and used in these fields.

[0053] Compared with the prior art, the positive effects of the present invention are:

[0054] (1) The introduction of trace amounts of allophanate greatly improves the product's resistance.

[0055] (2) A trace amount of urea formate combined with an appropriate amount of ether bonds maintains the initial viscosity of the product. DETAILED DESCRIPTION

[0056] The preferred embodiments of the present invention will be described in more detail below. Although the preferred embodiments of the present invention are shown in the examples, it should be understood that the present invention can be implemented in various forms and should not be limited by the embodiments described herein.

[0057] I. Theoretical Calculation

[0058] NCO 理论 % = (n NCO - n OH - 2n 水 ) / m 总 × 100%

[0059] n NCO : The total molar amount of NCO groups in the prepolymer raw materials

[0060] n OH : The total molar amount of OH groups in the prepolymer raw materials

[0061] n 水 : The total molar amount of water in the prepolymer raw materials

[0062] m 总 : The total mass of the prepolymer raw materials including the solvent

[0063] II. Test Methods:

[0064] NCO Test: NCO is tested by a Metrohm 905 automatic potentiometric titrator.

[0065] Particle Size Test: Measured using a Malvern particle size analyzer at 25 °C according to the WHPU / T011 - 682 - 2015 standard;

[0066] Urethane Test: The prepolymer is formulated into a deuterated chloroform solution with a mass concentration of 5%. The 1H spectrum is scanned using a Bruker Ascend 600M spectrometer. The peak positions of urethane and carbamate are 8.55 ppm and 4.84 ppm respectively. The content of urethane is calculated by the ratio of urethane to carbamate.

[0067] II. Raw Material Sources:

[0068] PBA1000: Poly(butylene adipate) diol, number average molecular weight 999 g / mol, OH value = 112.28 mg KOH / g, water content 130 ppm, purchased from Wanhua Chemical Group Co., Ltd., product number WHP_104;

[0069] PBA2000: Poly(1,4 - butanediol adipate) diol, number - average molecular weight 1998 g / mol, OH value = 56.14 mg KOH / g, water content 94 ppm, purchased from Wanhua Chemical Group Co., Ltd., product grade WHP_204;

[0070] HDI: Purchased from Wanhua Chemical Group Co., Ltd., product grade: HDI;

[0071] IPDI: Purchased from Wanhua Chemical Group Co., Ltd., product grade: IPDI;

[0072] MPEG1200: Polyethylene glycol monomethyl ether, number - average molecular weight 1200 g / mol, purchased from Wokai, hydroxyl value 46.80 mg KOH / g, containing ether bonds 22.1 mmol / g, water content 260 ppm after dehydration treatment at 110 °C;

[0073] MPEG2000: Polyethylene glycol monomethyl ether, number - average molecular weight 2004 g / mol, purchased from Clariant, hydroxyl value 28.00 mg KOH / g, containing ether bonds 22.4 mmol / g, water content 230 ppm after dehydration treatment at 110 °C;

[0074] Sulfonic acid polyether Ⅰ: Polyoxypropylene glycol with sodium sulfonate groups, its molar mass is 424 g / mol, hydroxyl value 264.71 mg KOH / g, containing ether bonds 9.43 mmol / g, water content 850 ppm, purchased from Wanhua Chemical.

[0075] PPG1000: Polypropylene glycol, number - average molecular weight 1000 g / mol, purchased from Wanhua Chemical, hydroxyl value 112.80 mg KOH / g, containing ether bonds 16.7 mmol / g, water content 170 ppm after dehydration treatment at 110 °C.

[0076] F3056D: Tri - functional polyether polyol, number - average molecular weight 3000 g / mol, purchased from Wanhua Chemical, hydroxyl 56.13 mg KOH / g, containing ether bonds 16.7 mmol / g, water content 210 ppm after dehydration treatment at 110 °C.

[0077] Acetone: Recycled and refined by Wanhua's water - based device, water content 210 ppm.

[0078] 1,4 - Butanediol: Purchased from Sinopharm Reagent, purity 99%, water content 327 ppm after dehydration.

[0079] 1,6 - Hexanediol: Purchased from Sinopharm Reagent, purity 98%, water content 280 ppm after dehydration.

[0080] Sodium N-(2-aminoethyl)-2-aminoethanesulfonate: 50% aqueous solution, purchased from Wanhua Chemical.

[0081] Hydroxyethylethylenediamine: purchased from Sinopharm Reagent, purity 98.0%.

[0082] Ethylenediamine: purchased from Aladdin Reagent, purity 99%.

[0083] Tween 20: purchased from Sinopharm Reagent.

[0084] Example 1

[0085] 300g polyester PBA2000, 5g MPEG1200, 34.8g HDI, 34g acetone, 0.04g bismuth neodecanoate were added to a 1L stainless steel reactor replaced with dry nitrogen under nitrogen atmosphere, and the mixture was stirred at 75°C. After reacting for 3h, NCO 1.19wt% (0.00wt% lower than theoretical NCO) was measured, and NCO 1.19wt% was measured after continuing the reaction for 2h. The prepolymer was dissolved in 476g acetone and cooled to 50°C. 33g aqueous solution containing 2.75g sodium N-(2-aminoethyl)-2-aminoethanesulfonic acid and 1g hydroxyethylethylenediamine was added to the acetone solution containing the prepolymer and stirred vigorously. The mixture was dispersed by adding 344g water. Acetone was then separated by distillation, 3.4g emulsifier Tween 20 was added, and water was added to adjust the solid content. A solvent-free aqueous polyurethane-polyurea dispersion was obtained which had a solids content of 50% by weight and an average particle size in the dispersed phase of 185 nm, determined by laser correlation (laser particle sizer).

[0086] Theoretical value of NCO: 1.19 wt%

[0087] Ether bond content: 325.2μmol / g

[0088] Allophanate content: 1.1 μmol / g.

[0089] Example 2

[0090] 300 g of polyester PBA2000, 5 g of MPEG1200, 34.15 g of HDI, 0.9 g of IPDI, 34 g of acetone, and 0.04 g of bismuth neodecanoate were added to a 1 L stainless steel reactor purged with dry nitrogen under a nitrogen atmosphere. The mixture was stirred at 90 °C, and after reacting for 3 h, the NCO was measured to be 1.18 wt% (0.01 wt% lower than the theoretical NCO). The prepolymer was dissolved in 476 g of acetone and cooled to 50 °C. A 33 g aqueous solution containing 2.75 g of N-(2-aminoethyl)-2-aminoethanesulfonic acid sodium salt and 1 g of hydroxyethyl ethylenediamine was added to the acetone solution containing the prepolymer and stirred vigorously. The mixture was dispersed by adding 344 g of water. Subsequently, acetone was separated by distillation, 3.4 g of emulsifier Tween 20 was added, and water was added to adjust the solid content. A solvent-free polyurethane-polyurea aqueous dispersion was obtained, which had a solid content of 50 wt% and an average particle size of 180 nm measured by laser correlation (laser particle size analyzer) in the dispersion phase.

[0091] Theoretical value of NCO: 1.19 wt%

[0092] Ether bond content: 325.8 μmol / g

[0093] Allophanate content: 2.4 μmol / g.

[0094] Example 3

[0095] 300 g of polyester PBA2000, 5 g of MPEG1200, 34.8 g of HDI, 34 g of acetone, and 0.13 g of bismuth neodecanoate were added to a 1 L stainless steel reactor purged with dry nitrogen under a nitrogen atmosphere. The mixture was stirred at 90 °C, and after reacting for 2 h, the NCO was measured to be 1.17 wt% (0.02 wt% lower than the theoretical NCO). The prepolymer was dissolved in 476 g of acetone and cooled to 50 °C. A 33 g aqueous solution containing 2.75 g of N-(2-aminoethyl)-2-aminoethanesulfonic acid sodium salt and 1 g of hydroxyethyl ethylenediamine was added to the acetone solution containing the prepolymer and stirred vigorously. The mixture was dispersed by adding 344 g of water. Subsequently, acetone was separated by distillation, 3.4 g of emulsifier Tween 20 was added, and water was added to adjust the solid content. A solvent-free polyurethane-polyurea aqueous dispersion was obtained, which had a solid content of 50 wt% and an average particle size of 191 nm measured by laser correlation (laser particle size analyzer) in the dispersion phase.

[0096] Theoretical value of NCO: 1.19 wt%

[0097] Ether bond content: 325.2 μmol / g

[0098] Allophanate content: 4.2 μmol / g.

[0099] Example 4

[0100] 300 g of polyester PBA2000, 5 g of MPEG1200, 34.8 g of HDI, and 0.13 g of bismuth neodecanoate were added to a 1 L stainless steel reactor purged with dry nitrogen under a nitrogen atmosphere. The mixture was stirred at 100 °C, and after reacting for 3 h, the NCO was measured to be 1.28 (0.04 wt% lower than the theoretical NCO)%. The prepolymer was dissolved in 510 g of acetone and cooled to 50 °C. A 33 g aqueous solution containing 2.75 g of N-(2-aminoethyl)-2-aminoethanesulfonic acid sodium salt and 1 g of hydroxyethyl ethylenediamine was added to the acetone solution containing the prepolymer and stirred vigorously. The mixture was dispersed by adding 344 g of water. Subsequently, acetone was separated by distillation, 3.4 g of emulsifier Tween 20 was added, and water was added to adjust the solid content. A solvent-free polyurethane-polyurea aqueous dispersion was obtained, which had a solid content of 50 wt% and an average particle size of 205 nm measured by laser correlation (laser particle size analyzer) in the dispersion phase.

[0101] Theoretical value of NCO: 1.32 wt%

[0102] Ether bond content: 325.2 μmol / g

[0103] Allophanate content: 9.3 μmol / g.

[0104] Example 5

[0105] 300 g of polyester PBA2000, 5 g of MPEG2000, 34.7 g of HDI, and 0.04 g of zinc neodecanoate were added to a 1 L stainless steel reactor purged with dry nitrogen under a nitrogen atmosphere. The mixture was stirred at 100 °C, and after reacting for 3 h, the NCO was measured to be 1.19 wt% (0.13 wt% lower than the theoretical NCO). The prepolymer was dissolved in 612 g of acetone and cooled to 50 °C. A 33 g aqueous solution containing 2.75 g of N-(2-aminoethyl)-2-aminoethanesulfonic acid sodium salt and 1 g of hydroxyethyl ethylenediamine was added to the acetone solution containing the prepolymer and stirred vigorously. The mixture was dispersed by adding 344 g of water. Subsequently, acetone was separated by distillation, 3.4 g of emulsifier Tween 20 was added, and water was added to adjust the solid content. A solvent-free polyurethane-polyurea aqueous dispersion was obtained, which had a solid content of 50 wt% and an average particle size of 225 nm measured by laser correlation (laser particle size analyzer) in the dispersion phase.

[0106] Theoretical value of NCO: 1.32 wt%

[0107] Ether bond content: 329.7 μmol / g

[0108] Urethane content: 29.2 μmol / g.

[0109] Example 6

[0110] 300 g of polyester PBA2000, 0.5 g of PPG1000, 34.9 g of HDI, 33.5 g of acetone, and 0.13 g of bismuth neodecanoate were added to a 1 L stainless steel reactor purged with dry nitrogen under a nitrogen atmosphere. The mixture was stirred at 90 °C, and after reacting for 3 h, the NCO was measured to be 1.23 wt% (0.03 wt% lower than the theoretical NCO). The prepolymer was dissolved in 470 g of acetone and cooled to 50 °C. A 42 g aqueous solution containing 4 g of N-(2-aminoethyl)-2-aminoethanesulfonic acid sodium salt and 0.3 g of hydroxyethyl ethylenediamine was added to the acetone solution containing the prepolymer and stirred vigorously. The mixture was dispersed by adding 340 g of water. Subsequently, acetone was separated by distillation, 3.4 g of emulsifier Tween 20 was added, and water was added to adjust the solid content. A solvent-free polyurethane-polyurea aqueous dispersion was obtained, which had a solid content of 50 wt% and an average particle size of 182 nm measured by laser correlation (laser particle size analyzer) in the dispersion phase.

[0111] Theoretical value of NCO: 1.26 wt%

[0112] Ether bond content: 24.9 μmol / g

[0113] Urethane content: 5.1 μmol / g.

[0114] Example 7

[0115] 300 g of polyester PBA2000, 1.1 g of PPG1000, 35 g of HDI, 34 g of acetone, and 0.13 g of bismuth neodecanoate were added to a 1 L stainless steel reactor purged with dry nitrogen under a nitrogen atmosphere. The mixture was stirred at 90 °C, and after reacting for 3 h, the NCO was measured to be 1.23 wt% (0.02 wt% lower than the theoretical NCO). The prepolymer was dissolved in 471 g of acetone and cooled to 50 °C. A 42 g aqueous solution containing 4 g of N-(2-aminoethyl)-2-aminoethanesulfonic acid sodium salt and 0.3 g of hydroxyethyl ethylenediamine was added to the acetone solution containing the prepolymer and stirred vigorously. The mixture was dispersed by adding 335 g of water. Subsequently, acetone was separated by distillation, 3.4 g of emulsifier Tween 20 was added, and water was added to adjust the solid content. A solvent-free polyurethane-polyurea aqueous dispersion was obtained, which had a solid content of 50 wt% and an average particle size of 177 nm measured by laser correlation (laser particle size analyzer) in the dispersion phase.

[0116] Theoretical value of NCO: 1.25 wt%

[0117] Ether bond content: 54.7 μmol / g

[0118] Allophanate content: 4.6 μmol / g.

[0119] Example 8

[0120] 300 g of polyester PBA2000, 1.1 g of F3056D, 1.1 g of MPEG1200, 34.95 g of HDI, 34 g of acetone, and 0.13 g of bismuth neodecanoate were added to a 1 L stainless steel reactor purged with dry nitrogen under a nitrogen atmosphere. The mixture was stirred at 90 °C, and after reacting for 3 h, the NCO was measured to be 1.22 wt% (0.02 wt% lower than the theoretical NCO). The prepolymer was dissolved in 472 g of acetone and cooled to 50 °C. A 40 g aqueous solution containing 3.7 g of N-(2-aminoethyl)-2-aminoethanesulfonic acid sodium salt and 0.4 g of hydroxyethyl ethylenediamine was added to the acetone solution containing the prepolymer and stirred vigorously. The mixture was dispersed by adding 336 g of water. Subsequently, acetone was separated by distillation, 3.4 g of emulsifier Tween 20 was added, and water was added to adjust the solid content. A solvent-free aqueous dispersion of polyurethane-polyurea was obtained, which had a solid content of 50 wt% and an average particle size of 185 nm measured by laser correlation (laser particle size analyzer) in the dispersion phase.

[0121] Theoretical value of NCO: 1.24 wt%

[0122] Ether bond content: 126.6 μmol / g

[0123] Allophanate content: 3.9 μmol / g.

[0124] Example 9

[0125] 300 g of polyester PBA2000, 8 g of PPG1000, 5 g of MPEG1200, 1 g of 1,4-butanediol, 38.3 g of HDI, 35 g of acetone, and 0.13 g of bismuth neodecanoate were added into a 1 L stainless steel reactor replaced with dry nitrogen under a nitrogen atmosphere. The mixture was stirred at 90 °C. After reacting for 3 h, the NCO was measured to be 1.16 wt% (0.02 wt% lower than the theoretical NCO). The prepolymer was dissolved in 489 g of acetone and cooled to 50 °C. A 35 g aqueous solution containing 2.75 g of N-(2-aminoethyl)-2-aminoethanesulfonic acid sodium salt and 1 g of hydroxyethyl ethylenediamine was added to the acetone solution containing the prepolymer and stirred vigorously. The mixture was dispersed by adding 349 g of water. Subsequently, acetone was separated by distillation, 3.5 g of emulsifier Tween 20 was added, and water was added to adjust the solid content. A solvent-free water dispersion of polyurethane-polyurea was obtained, which had a solid content of 50 wt% and an average particle size of 187 nm measured by laser correlation (laser particle size analyzer) in the dispersion phase.

[0126] Theoretical value of NCO: 1.18 wt%

[0127] Ether bond content: 692.9 μmol / g

[0128] Allophanate content: 5.4 μmol / g.

[0129] Example 10

[0130] 300 g of polyester PBA2000, 14 g of PPG1000, 5 g of MPEG1200, 1 g of 1,6-hexanediol, 39.2 g of HDI, 36 g of acetone, and 0.13 g of bismuth neodecanoate were added into a 1 L stainless steel reactor replaced with dry nitrogen under a nitrogen atmosphere. The mixture was stirred at 90 °C. After reacting for 3 h, the NCO was measured to be 1.18 wt% (0.02 wt% lower than the theoretical NCO). The prepolymer was dissolved in 499 g of acetone and cooled to 50 °C. A 35 g aqueous solution containing 2.75 g of N-(2-aminoethyl)-2-aminoethanesulfonic acid sodium salt, 0.4 g of hydroxyethyl ethylenediamine, and 0.4 g of ethylenediamine was added to the acetone solution containing the prepolymer and stirred vigorously. The mixture was dispersed by adding 357 g of water. Subsequently, acetone was separated by distillation, 3.6 g of emulsifier Tween 20 was added, and water was added to adjust the solid content. A solvent-free water dispersion of polyurethane-polyurea was obtained, which had a solid content of 50 wt% and an average particle size of 176 nm measured by laser correlation (laser particle size analyzer) in the dispersion phase.

[0131] Theoretical value of NCO: 1.20 wt%

[0132] Ether bond content: 958.5 μmol / g

[0133] Urethane content: 4.5 μmol / g.

[0134] Example 11

[0135] 300 g of polyester PBA2000, 39.5 g of PPG1000, 5 g of MPEG1200, 42.9 g of HDI, 39 g of acetone, and 0.13 g of bismuth neodecanoate were added to a 1 L stainless steel reactor purged with dry nitrogen under a nitrogen atmosphere. The mixture was stirred at 90 °C, and after reacting for 3 h, the NCO was measured to be 1.18 wt% (0.02 wt% lower than the theoretical NCO). The prepolymer was dissolved in 543 g of acetone and cooled to 50 °C. A 35 g aqueous solution containing 2.75 g of N-(2-aminoethyl)-2-aminoethanesulfonic acid sodium salt and 1.4 g of hydroxyethyl ethylenediamine was added to the acetone solution containing the prepolymer and stirred vigorously. The mixture was dispersed by adding 388 g of water. Subsequently, acetone was separated by distillation, 3.9 g of emulsifier Tween 20 was added, and water was added to adjust the solid content. A solvent-free polyurethane-polyurea aqueous dispersion was obtained, which had a solid content of 50 wt% and an average particle size of 189 nm measured by laser correlation (laser particle size analyzer) in the dispersion phase.

[0136] Theoretical value of NCO: 1.20 wt%

[0137] Ether bond content: 1988.0 μmol / g

[0138] Urethane content: 4.7 μmol / g.

[0139] Example 12

[0140] 300 g of polyester PBA2000, 16 g of sulfonic acid polyether I, 41.9 g of HDI, 35 g of acetone, and 0.13 g of bismuth neodecanoate were added to a 1 L four-necked round-bottom flask under a nitrogen atmosphere. The mixture was stirred at 90 °C, and after reacting for 4 h, the NCO was measured to be 1.23 wt% (0.02 wt% lower than the theoretical NCO). The prepolymer was dissolved in 250 g of acetone and cooled to 35 °C. The mixture was dispersed by adding 357 g of water. After the dispersion was completed, a 20 g aqueous solution containing 2.8 g of hydroxyethyl ethylenediamine was added, and stirring was continued for 15 min. Subsequently, acetone was separated by distillation, 3.6 g of emulsifier Tween 20 was added, and water was added to adjust the solid content. A solvent-free polyurethane-polyurea aqueous dispersion was obtained, which had a solid content of 50 wt% and an average particle size of 167 nm measured by laser correlation (laser particle size analyzer) in the dispersion phase.

[0141] Theoretical value of NCO: 1.25 wt%

[0142] Ether bond content: 421.6 μmol / g

[0143] Allophanate content: 4.4 μmol / g.

[0144] Comparative Example 1

[0145] Compared with Example 3, the difference is that the allophanate is lower than the lower limit value.

[0146] 300 g of polyester PBA2000, 5 g of MPEG1200, 34.8 g of HDI, 34 g of acetone, and 0.04 g of bismuth neodecanoate were added to a 1 L stainless steel reactor purged with dry nitrogen under a nitrogen atmosphere. The mixture was stirred at 75 °C. After reacting for 3 h, the NCO was measured to be 1.19 wt% (0.00 wt% lower than the theoretical NCO). The prepolymer was dissolved in 476 g of acetone and cooled to 50 °C. A 33 g aqueous solution containing 2.75 g of N-(2-aminoethyl)-2-aminoethanesulfonic acid sodium salt and 1 g of hydroxyethyl ethylenediamine was added to the acetone solution containing the prepolymer and stirred vigorously. The mixture was dispersed by adding 344 g of water. Subsequently, acetone was separated by distillation, 3.4 g of emulsifier Tween 20 was added, and water was added to adjust the solid content. A solvent-free polyurethane-polyurea aqueous dispersion was obtained, which had a solid content of 50 wt% and an average particle size of 191 nm measured by laser correlation (laser particle size analyzer) in the dispersion phase.

[0147] Theoretical value of NCO: 1.19 wt%

[0148] Ether bond content: 325.2 μmol / g

[0149] Allophanate content: Not detected.

[0150] Comparative Example 2

[0151] Compared with Example 3, the difference is that the ether bond is lower than the lower limit value.

[0152] 300 g of polyester PBA2000, 34.15 g of HDI, 34 g of acetone, and 0.13 g of bismuth neodecanoate were added to a 1 L stainless steel reactor purged with dry nitrogen under a nitrogen atmosphere. The mixture was stirred at 90 °C, and after reacting for 2 h, the NCO was measured to be 1.24 wt% (0.02 wt% lower than the theoretical NCO). The prepolymer was dissolved in 476 g of acetone and cooled to 50 °C. A 33 g aqueous solution containing 4 g of N-(2-aminoethyl)-2-aminoethanesulfonic acid sodium salt and 0.3 g of hydroxyethyl ethylenediamine was added to the acetone solution containing the prepolymer and stirred vigorously. The mixture was dispersed by adding 344 g of water. Subsequently, acetone was separated by distillation, 3.4 g of emulsifier Tween 20 was added, and water was added to adjust the solid content. A solvent-free polyurethane-polyurea aqueous dispersion was obtained, which had a solid content of 50 wt% and an average particle size of 193 nm measured by laser correlation (laser particle size analyzer) in the dispersion phase.

[0153] Theoretical value of NCO: 1.26 wt%

[0154] Ether bond content: 0 μmol / g

[0155] Allophanate content: 3.7 μmol / g.

[0156] Comparative Example 3

[0157] Compared with Example 3, the difference is that the ether bond is lower than the lower limit value and the allophanate is lower than the lower limit value.

[0158] 300 g of polyester PBA2000, 34.8 g of HDI, 34 g of acetone, and 0.04 g of bismuth neodecanoate were added to a 1 L stainless steel reactor purged with dry nitrogen under a nitrogen atmosphere. The mixture was stirred at 75 °C, and after reacting for 3 h, the NCO was measured to be 1.26 wt% (0.00 wt% lower than the theoretical NCO). The prepolymer was dissolved in 476 g of acetone and cooled to 50 °C. A 33 g aqueous solution containing 4 g of N-(2-aminoethyl)-2-aminoethanesulfonic acid sodium salt and 0.3 g of hydroxyethyl ethylenediamine was added to the acetone solution containing the prepolymer and stirred vigorously. The mixture was dispersed by adding 344 g of water. Subsequently, acetone was separated by distillation, 3.4 g of emulsifier Tween 20 was added, and water was added to adjust the solid content. A solvent-free polyurethane-polyurea aqueous dispersion was obtained, which had a solid content of 50 wt% and an average particle size of 182 nm measured by laser correlation (laser particle size analyzer) in the dispersion phase.

[0159] Theoretical value of NCO: 1.26 wt%

[0160] Ether bond content: 0 μmol / g

[0161] Allophanate content: Not detected

[0162] Comparative Example 4

[0163] Compared with Example 3, the difference is that the urethane exceeds the upper limit value.

[0164] 300 g of polyester PBA2000, 5 g of MPEG1200, 34.8 g of HDI, and 0.04 g of zinc neodecanoate were added to a 1 L stainless steel reactor purged with dry nitrogen under a nitrogen atmosphere. The mixture was stirred at 110 °C, and after reacting for 3 h, the NCO was measured to be 1.16 wt% (0.16 wt% lower than the theoretical NCO). The prepolymer was dissolved in 612 g of acetone and cooled to 50 °C. A 33 g aqueous solution containing 2.75 g of N-(2-aminoethyl)-2-aminoethanesulfonic acid sodium salt and 1 g of hydroxyethyl ethylenediamine was added to the acetone solution containing the prepolymer and stirred vigorously. The mixture was dispersed by adding 344 g of water. Subsequently, acetone was separated by distillation, 3.4 g of emulsifier Tween 20 was added, and water was added to adjust the solid content. A solvent-free polyurethane-polyurea aqueous dispersion was obtained, which had a solid content of 50 wt% and an average particle diameter of 241 nm measured by laser correlation (laser particle size analyzer) in the dispersion phase.

[0165] Theoretical value of NCO: 1.32 wt%

[0166] Ether bond content: 325.2 μmol / g

[0167] Urethane content: 38.7 μmol / g.

[0168] Comparative Example 5

[0169] Compared with Example 3, the difference is that the ether bond exceeds the upper limit value and the urethane exceeds the upper limit value.

[0170] 300 g of polyester PBA2000, 5 g of MPEG1200, 50 g of PPG1000, 45 g of HDI, and 0.04 g of zinc neodecanoate were added to a 1 L stainless steel reactor purged with dry nitrogen under a nitrogen atmosphere. The mixture was stirred at 110 °C, and after reacting for 3 h, the NCO was measured to be 1.16 wt% (0.16 wt% lower than the theoretical NCO). The prepolymer was dissolved in 612 g of acetone and cooled to 50 °C. A 33 g aqueous solution containing 2.75 g of N-(2-aminoethyl)-2-aminoethanesulfonic acid sodium salt and 1.5 g of hydroxyethyl ethylenediamine was added to the acetone solution containing the prepolymer and stirred vigorously. The mixture was dispersed by adding 344 g of water. Subsequently, acetone was separated by distillation, 3.4 g of emulsifier Tween 20 was added, and water was added to adjust the solid content. A solvent-free polyurethane-polyurea aqueous dispersion was obtained, which had a solid content of 50 wt% and an average particle size of 217 nm measured by laser correlation (laser particle size analyzer) in the dispersion phase.

[0171] Theoretical value of NCO: 1.32 wt%

[0172] Ether bond content: 2363.8 μmol / g

[0173] Allophanate content: 36.6 μmol / g.

[0174] Comparative Example 6

[0175] Compared with Example 3, the difference is that the ether bond exceeds the upper limit value and the allophanate is lower than the lower limit value.

[0176] 300 g of polyester PBA2000, 5 g of MPEG1200, 50 g of PPG1000, 45 g of HDI, 40 g of acetone, and 0.04 g of bismuth neodecanoate were added to a 1 L stainless steel reactor purged with dry nitrogen under a nitrogen atmosphere. The mixture was stirred at 75 °C, and after reacting for 3 h, the NCO was measured to be 1.20 wt% (0.00 wt% lower than the theoretical NCO). The prepolymer was dissolved in 476 g of acetone and cooled to 50 °C. A 33 g aqueous solution containing 2.75 g of N-(2-aminoethyl)-2-aminoethanesulfonic acid sodium salt and 1.5 g of hydroxyethyl ethylenediamine was added to the acetone solution containing the prepolymer and stirred vigorously. The mixture was dispersed by adding 344 g of water. Subsequently, acetone was separated by distillation, 3.4 g of emulsifier Tween 20 was added, and water was added to adjust the solid content. A solvent-free polyurethane-polyurea aqueous dispersion was obtained, which had a solid content of 50 wt% and an average particle size of 182 nm measured by laser correlation (laser particle size analyzer) in the dispersion phase.

[0177] Theoretical value of NCO: 1.20 wt%

[0178] Ether bond content: 2363.8 μmol / g

[0179] Urethane content: 0.2 μmol / g.

[0180] Preparation of one-component adhesive:

[0181] Mix 100 g of aqueous dispersion and 0.05 g of BYK024 (BYK-Chemie), stir at 500 rpm for 5 min, add 0.2 g of Tego245 (Degussa), stir for another 5 min, then add 0.25 g of Vesmody U604 (Wanhua Chemical), and then stir at 600 rpm for 10 min.

[0182] Preparation of two-component adhesive:

[0183] Take 100 g of one-component adhesive, add 5 g of Aquolin 161 (Wanhua Chemical), and then stir at 600 rpm for 10 min.

[0184] Preparation of specimens:

[0185] First, treat the substrate with a treatment agent and then air dry for later use. Gently brush the adhesive onto a 10-cm long rubber strip that has been treated with the brush three times back and forth. Another rubber strip is treated in the same way. At the same time, place the two rubber strips in an oven at 65 °C, take them out after drying for 3 minutes, press them against each other at 30 kg / cm2 for 10 s, and place them at room temperature for later use.

[0186] Performance testing:

[0187] Initial tack: Fold two rubber strips into an arc shape and gently contact them vertically against each other within 1 minute. Score the tack according to the magnitude of the force required to separate them after contact. (The scores range from A0 - A5, with higher scores indicating better tack)

[0188] Initial heat resistance: Hang a 500-gram weight on the prepared specimen and place it in an oven at 80 °C. Measure the length by which the specimen separates within 30 minutes.

[0189] Humidity and heat resistance: Place the prepared specimen at room temperature for 3 days, hang a 1000-gram weight on it, and place it in an oven at 70 °C / 95% humidity. Measure the length by which the specimen separates within 8 hours.

[0190] The test results are shown in Table 1:

[0191] Table 1 Test results of two-component adhesive

[0192] Sample Theoretical NCO Actual NCO Ether bond content Urea bond content Initial adhesion Heat resistance Humidity and heat resistance Example 1 1.19 1.19 325.2 1.1 A3.5 2mm 25mm Example 2 1.19 1.18 325.8 2.4 A3.5 1mm 5mm Example 3 1.19 1.17 325.2 4.2 A3.5 1mm 2mm Example 4 1.32 1.28 325.2 9.3 A3.5 1mm 1mm Example 5 1.32 1.19 329.7 29.2 A3 0mm 0mm Example 6 1.26 1.23 24.9 5.1 A3 1mm 2mm Example 7 1.25 1.23 53.7 4.6 A3.3 1mm 1mm Example 8 1.24 1.22 126.6 3.9 A3.5 0mm 2mm Example 9 1.18 1.16 692.9 5.4 A3.5 1mm 3mm Example 10 1.20 1.18 958.5 4.5 A3.2 2mm 6mm Example 11 1.20 1.18 1988.0 4.7 A3 8mm 17mm Example 12 1.25 1.23 421.6 4.4 A3.5 1mm 2mm Comparative Example 1 1.19 1.19 325.2 Not detected A3.5 7mm Completely peeled off Comparative Example 2 1.26 1.24 0 3.7 A2 1mm 2mm Comparative Example 3 1.26 1.26 0 Not detected A3.5 2mm 60mm Comparative Example 4 1.32 1.16 325.2 38.7 A2 0mm 1mm Comparative Example 5 1.32 1.16 2363.8 36.6 A1.5 1mm 4mm Comparative Example 6 1.20 1.20 2363.8 0.2 A2 25mm Completely peeled off

[0193] It can be seen from the comparison between Examples 1, 2, 3, 4, 8, 9 and Comparative Examples 1 and 3 that by incorporating a small amount of urethane and ether bonds in the polyurethane, the initial heat resistance, humidity resistance and other properties of the product can be significantly improved without affecting the initial tackiness of the polyurethane-urea.

Claims

1. A polyurethane-urea aqueous dispersion, characterized in that, The polyurethane or polyurethane-urea is a reaction product obtained by reacting a composition comprising the following components: a) at least one polyol component having a functionality of 2 to 4; b) at least one polyisocyanate component; c) at least one hydrophilic compound component, the hydrophilic group of the hydrophilic compound comprising one or both of an ionic group and a latent ionic group, the hydrophilic compound having 2 to 3 isocyanate-reactive groups; the ionic group is preferably a carboxylate group and / or a sulfonate group; the latent ionic group is preferably a carboxyl group and / or a sulfonic acid group; the isocyanate-reactive group is preferably a hydroxyl group and / or an amino group; d) an optional component of an isocyanate-reactive nonionic hydrophilic compound; e) an optional small molecule alcohol chain extender; f) an optional compound having 1 to 3 amino groups and / or hydroxyl groups in the molecule; In the reaction product, the ether bond content is 20 μmol / g to 2000 μmol / g based on the mass of the reaction product, preferably 50 μmol / g to 1000 μmol / g, more preferably 100 μmol / g to 700 μmol / g; In the reaction product, the content of urethane is 1 μmol / g to 30 μmol / g based on the mass of the reaction product, preferably 2 μmol / g to 10 μmol / g.

2. The aqueous polyurethane-urea dispersion according to claim 1, wherein The urethane content is obtained by controlling the residual NCO content after the reaction to be 0.01 wt% to 0.13 wt% lower than the theoretical value, or by extending the reaction time by more than 50% after the NCO content reaches the theoretical value and keeping the NCO constant. The NCO theoretical value is calculated from the hydroxyl value and water content of the raw materials.

3. The aqueous polyurethane-urea dispersion according to claim 1 or 2, characterized in that, The component a) is a diol and / or polyol having a number average molecular weight of 400 to 10,000; preferably a diol and / or polyol having a number average molecular weight of 1000 to 5000; more preferably one or more of a polyester, a polycarbonate, a polylactone polyol, a polyether polyol, and a polyurethane polyol having a functionality of 2 to 3 and a number average molecular weight of 1000 to 3000.

4. The aqueous polyurethane-urea dispersion according to any one of claims 1-3, characterized in that The component b) polyisocyanate is an organic compound having at least two isocyanate groups, preferably a diisocyanate, more preferably one or more of tetramethylene diisocyanate, pentamethylene diisocyanate, hexamethylene diisocyanate, dodecamethylene diisocyanate, 1,4-cyclohexane diisocyanate, isophorone diisocyanate, 4,4'-dicyclohexylmethane diisocyanate, 4,4'-dicyclopropylpropane diisocyanate, 1,4-phenylene diisocyanate, 2,4-toluene diisocyanate, 2,6-toluene diisocyanate, 4,4'-diphenylmethane diisocyanate, 2,2'- and 2,4'-diphenylmethane diisocyanate, tetramethylxylene diisocyanate, and p-phenylene dimethylene diisocyanate, and further preferably one or more of hexamethylene diisocyanate, isophorone diisocyanate, and 4,4'-dicyclohexylmethane diisocyanate.

5. The aqueous polyurethane-urea dispersion according to any one of claims 1-4, characterized in that, The hydrophilic compound containing ionic groups and / or latent ionic groups in component c) includes one or more of dimethylolacetic acid, dimethylolpropionic acid, dimethylolbutyric acid, dihydroxysuccinic acid, N-(2-aminoethyl)-2-aminoethanesulfonic acid, N-(3-aminopropyl)-2-aminoethanesulfonic acid, N-(3-aminopropyl)-3-aminopropanesulfonic acid, N-(2-aminoethyl)-3-aminopropanesulfonic acid, polyether sulfonic acid and its alkali metal salts, polyether sulfonic acid and its alkaline earth metal salts, and polyether sulfonic acid and its ammonium salts.

6. The aqueous polyurethane-urea dispersion according to any one of claims 1-5, characterized in that, Component d) is selected from polyoxyethylene ethers and / or polyoxyethylene-polyoxypropylene copolymers containing at least one hydroxyl group and / or amino group, preferably polyoxyethylene ethers and / or polyoxyethylene-polyoxypropylene copolymers containing only one hydroxyl group, more preferably polyoxyethylene ethers containing only one hydroxyl group; Preferably, the number of ethylene oxide units in each molecule of the polyoxyethylene ether is 4 to 200, preferably 12 to 75; Preferably, the polyoxyethylene ether is a polyoxyethylene ether with a number average molecular weight of 200 to 8000 and 4 to 200 ethylene oxide units, preferably polyethylene glycol monomethyl ether with a number average molecular weight of 500 to 3500 and 12 to 75 ethylene oxide units.

7. The aqueous polyurethane-urea dispersion according to any one of claims 1 to 6, characterized in that, The small molecule alcohol chain extender e) is a diol and / or polyol with a number average molecular weight of 60 to 400.

8. The aqueous polyurethane-urea dispersion according to any one of claims 1-7, characterized in that, Component f) is a compound containing 1 to 3 NCO-reactive functional groups. Preferably, at least one NCO-reactive functional group in component f) is a primary amino group or a secondary amino group. More preferably, component f) is one or more of ethylenediamine, isophoronediamine, and N-(2-hydroxyethyl)ethylenediamine.

9. A method for preparing the aqueous polyurethane-urea dispersion according to any one of claims 1-8, characterized in that, The method is as follows: React components a), b), c), d) and optionally e) in one or more steps to form a prepolymer with terminal isocyanate groups, then react the prepolymer with optionally f) in one or two stages, and then disperse or dissolve with water, where a solvent that can be partially or completely removed by distillation during or after dispersion is optionally used; or, React components a), b), d) and optionally e) in one or more steps to form a prepolymer with terminal isocyanate groups, then react the prepolymer with component c) and optionally f) in one or more stages, and then disperse or dissolve with water, where a solvent that can be partially or completely removed by distillation during or after dispersion is optionally used.

10. An aqueous polyurethane-urea dispersion according to any one of claims 1-8 or an aqueous polyurethane-urea dispersion prepared by the method according to claim 9.

11. Use of an aqueous polyurethane-urea dispersion according to any one of claims 1-8 or an aqueous polyurethane-urea dispersion prepared by the method according to claim 9 for preparing adhesives and sealants.

12. A method for manufacturing a coated film or an adhesive article, which includes the step of coating a composition of an aqueous polyurethane-urea dispersion according to any one of claims 1-8 or an aqueous polyurethane-urea dispersion prepared by the method according to claim 9 on a substrate.

13. A painted or adhered article having a coated and dried product of the aqueous polyurethane-urea dispersion according to any one of claims 1-8 or the aqueous polyurethane-urea dispersion composition prepared by the method of claim 9.