Solvent-free nonionic waterborne polyurethane resin as well as preparation method and application thereof

Abstract

The invention provides solvent-free nonionic waterborne polyurethane resin as well as a preparation method and application thereof. The solvent-free nonionic waterborne polyurethane resin is prepared from the following raw materials: polymer polyol, diisocyanate, nonionic hydrophilic polyol, an emulsifier, an amine chain extender and an amino silane coupling agent, non-ionic hydrophilic polyol is adopted as an internal hydrophilic chain extender, and an emulsifier is added for synergistic emulsification, so that the water resistance of the obtained waterborne polyurethane resin is effectively improved, the water swelling property of the waterborne polyurethane resin is reduced, the jungle stability of the waterborne polyurethane resin is improved, and the waterborne polyurethane resin has the characteristics that the solid content is relatively high, and acetone does not need to be removed; the water resistance and alkali resistance of the obtained waterborne polyurethane resin are further improved by further introducing an amine chain extender and an amino silane coupling agent, so that the waterborne polyurethane resin is applied to the field of waterborne microfiber leather, and the prepared waterborne microfiber leather is good in hand feeling, fine in crease, good in resilience and qualified in jungle test.

Description

Technical Field

[0001] The invention belongs to the technical field of polyurethane, and in particular relates to a solvent-free non-ionic waterborne polyurethane resin and a preparation method and application thereof. Background Art

[0002] Waterborne polyurethane is a new type of polyurethane system that uses water instead of organic solvents as a dispersion medium. It is also called water-dispersible polyurethane, water-based polyurethane or water-based polyurethane. Waterborne polyurethane uses water as a solvent and has the advantages of being pollution-free, safe and reliable, having excellent mechanical properties, good compatibility, and being easy to modify. Waterborne polyurethane resins have gradually replaced solvent-based ones and have become an important direction for the development of the polyurethane industry.

[0003] At present, the synthesis of water-based polyurethane for microfiber impregnation is mainly based on the acetone method, which introduces hydrophilic groups into the polyurethane prepolymer molecular chain, dilutes it with acetone, neutralizes it into salts and then disperses it in water, and then extracts the acetone to obtain a polyurethane emulsion. This method uses a large amount of acetone solvent during the synthesis process, and still does not fundamentally solve the pollution problem caused by the synthesis and application of water-based polyurethane.

[0004] In addition, with the gradual enhancement of human health and environmental awareness and the increasing depletion of petroleum resources, more and more stringent environmental regulations and export quality standards have been introduced one after another. The synthesis of solvent-free non-ionic waterborne polyurethane resins came into being in this environment.

[0005] CN118005884A reports a method for preparing a water-based polyurethane emulsion for water-reduced microfibers, and also discloses a water-reduced microfiber leather and a method for preparing the same, wherein the polyurethane emulsion can smoothly open water-soluble sea-island fibers. However, the preparation method provided by the invention requires the use of an organic solvent to reduce the viscosity of the prepolymer before emulsification and dispersion, which not only increases the process time accordingly, but also makes the preparation process environmentally unfriendly.

[0006] CN102432992A reports a method of using linear polyethylene glycol difunctional methyl ether instead of trimethylolpropane polyethoxy monomethyl ether, and then adding a small amount of ionic hydrophilic chain extender, but the added amount does not affect the non-ionic nature of the emulsion. The problem of large amount of non-ionic chain extender used and the emulsion being unstable and prone to stratification can be solved; however, this method introduces ionic groups after all, and its application surface exclusively in non-ionic polyurethane emulsions is also affected to a certain extent.

[0007] CN103102789A reports an aqueous nonionic antistatic coating resin and a preparation method thereof. In this method, polyethylene glycol monomethyl ether and small molecule polyethylene glycol are hydrophilic chain extenders, small molecule diols are used for chain extension, and diamines are used for chain extension after emulsification. The obtained emulsion has good storage stability, good film mechanical properties, and good friction charging properties that anionic polyurethane emulsions do not have. However, this method has the problem of introducing a large amount of low-boiling point solvents and the preparation process is not environmentally friendly.

[0008] Therefore, in view of the above technical problems, it is urgent to develop a solvent-free nonionic waterborne polyurethane resin that does not require acetone removal and has excellent comprehensive performance. Summary of the invention

[0009] In view of the deficiencies in the prior art, the object of the present invention is to provide a solvent-free non-ionic waterborne polyurethane resin and a preparation method and application thereof. The solvent-free non-ionic waterborne polyurethane resin has the characteristics of high solid content and no need to remove acetone, is very environmentally friendly, and has excellent solvent resistance, weather resistance, wear resistance, heat resistance, alkali resistance and mechanical properties, and is very suitable for the application of ultra-fiber impregnation.

[0010] To achieve this object, the present invention adopts the following technical solutions:

[0011] In a first aspect, the present invention provides a solvent-free nonionic waterborne polyurethane resin, wherein the raw materials of the solvent-free nonionic waterborne polyurethane resin include polymer polyol, diisocyanate, nonionic hydrophilic polyol, emulsifier, amine chain extender and aminosilane coupling agent.

[0012] The solvent-free nonionic waterborne polyurethane resin raw materials provided by the present invention include polymer polyols, diisocyanates, nonionic hydrophilic polyols, emulsifiers, amine chain extenders and aminosilane coupling agents. On the one hand, nonionic hydrophilic polyols are used as internal hydrophilic chain extenders, and external emulsifiers are added for coordinated emulsification, so that the prepared solvent-free nonionic waterborne polyurethane resin has a small emulsion particle size and good storage stability, which solves the problem that a large amount of acetone needs to be introduced into the emulsion synthesized by conventional methods, and the solid content is high, which truly realizes green and environmentally friendly production. In addition, due to the nonionic hydrophilic polyols used, the prepared solvent-free nonionic waterborne polyurethane resin has no charge, so it is not sensitive to various environmental factors such as acids, alkalis and electrolytes. Sensitive, effectively improving the water resistance of the obtained water-based polyurethane resin, reducing its water swelling performance, and improving its jungle stability; on the other hand, by further introducing amine chain extenders and aminosilane coupling agents, the water resistance and alkali resistance of the obtained solvent-free non-ionic water-based polyurethane resin are also improved, so that it can be used in the field of water-based microfiber leather, and can play a good wetting and protective role on the microfiber, as well as bonding and bundling effects, and will not change color at high temperature in light-colored products, can effectively prevent the accumulation of static charge on the surface of microfibers, and can enable the fibers to obtain good compatibility with the substrate and interfacial chemical bonding or chemical adsorption and other properties, so that the further prepared water-based microfiber leather has a good feel, fine creases, good resilience, and a normal jungle test.

[0013] Preferably, the raw materials of the solvent-free non-ionic waterborne polyurethane resin include the following components in parts by weight:

[0014] 200-400 parts by weight of polymer polyol;

[0015] 100-150 parts by weight of diisocyanate;

[0016] 15-35 parts by weight of nonionic hydrophilic polyol;

[0017] 15-25 parts by weight of emulsifier;

[0018] 12 to 25 parts by weight of an amine chain extender;

[0019] 5 to 10 parts by weight of aminosilane coupling agent.

[0020] Wherein, the weight of the polymer polyol can be 200 parts by weight, 220 parts by weight, 240 parts by weight, 260 parts by weight, 280 parts by weight, 300 parts by weight, 320 parts by weight, 340 parts by weight, 360 parts by weight, 380 parts by weight or 400 parts by weight, etc.

[0021] The weight of the diisocyanate can be 100 parts by weight, 105 parts by weight, 110 parts by weight, 115 parts by weight, 120 parts by weight, 125 parts by weight, 130 parts by weight, 135 parts by weight, 140 parts by weight, 145 parts by weight or 150 parts by weight, etc.

[0022] The weight of the nonionic hydrophilic polyol can be 15 parts by weight, 17 parts by weight, 19 parts by weight, 21 parts by weight, 23 parts by weight, 25 parts by weight, 27 parts by weight, 29 parts by weight, 31 parts by weight, 33 parts by weight or 35 parts by weight, etc.

[0023] The weight of the emulsifier can be 15 parts by weight, 16 parts by weight, 17 parts by weight, 18 parts by weight, 19 parts by weight, 20 parts by weight, 21 parts by weight, 22 parts by weight, 23 parts by weight, 24 parts by weight or 25 parts by weight, etc.

[0024] The weight of the amine chain extender can be 12 parts by weight, 14 parts by weight, 16 parts by weight, 18 parts by weight, 20 parts by weight, 22 parts by weight, 24 parts by weight or 25 parts by weight, etc.

[0025] The weight of the aminosilane coupling agent can be 5 parts by weight, 6 parts by weight, 7 parts by weight, 8 parts by weight, 9 parts by weight or 10 parts by weight.

[0026] Preferably, the number average molecular weight of the polymer polyol is 500-8000, for example, 500, 1000, 2000, 4000, 6000 or 8000.

[0027] Preferably, the polymer polyol comprises polyester polyol and / or polyether polyol.

[0028] Preferably, the polyether polyol includes any one of polytetramethylene oxide ether diol, polypropylene oxide ether diol, polypropylene oxide ether triol, polypropylene oxide / ethylene oxide ether diol or polypropylene oxide / ethylene oxide ether triol, or a combination of at least two thereof.

[0029] Preferably, the polyester polyol includes any one of polycarbonate diol, polycaprolactone diol, polyneopentyl adipate diol, polyhexane adipate diol or polybutylene adipate diol, or a combination of at least two thereof.

[0030] Preferably, the diisocyanate includes any one or a combination of at least two of hexamethylene diisocyanate (HDI), isophorone diisocyanate (IPDI), diphenylmethane-4,4-diisocyanate (MDI), dicyclohexylmethane diisocyanate (HMDI), tetramethylxylene diisocyanate (TMXDI) or toluene diisocyanate (TDI), and is more preferably any one or a combination of at least two of isophorone diisocyanate, dicyclohexylmethane diisocyanate, toluene diisocyanate, hexamethylene diisocyanate or diphenylmethane-4,4-diisocyanate.

[0031] Preferably, the number average molecular weight of the nonionic hydrophilic polyol is 500-8000, for example, 500, 1000, 2000, 4000, 6000 or 8000.

[0032] Preferably, the nonionic hydrophilic polyol includes any one of polyethylene oxide ether glycol, polyethylene oxide ether glycol monomethyl ether, polyethylene oxide ether glycol monoethyl ether, polypropylene oxide / ethylene oxide ether glycol monomethyl ether, polypropylene oxide / ethylene oxide ether glycol monoethyl ether or trimethylolpropane polyethoxy monomethyl ether, or a combination of at least two thereof.

[0033] Preferably, the emulsifier includes any one of Tween 80, Tween 85, Tween 60, Tween 20, Span 80, Span 85, Span 60, Span 20, C12-C14 fatty alcohol polyoxyethylene ether, fatty alcohol polyoxyethylene ether sodium sulfate, sodium dodecylbenzene sulfonate, alkylphenol polyoxyethylene ether, coconut acid diethanolamide, isomeric tridecyl alcohol polyoxyethylene ether, diethanolamide or ethylenediaminetetraacetic acid, or a combination of at least two thereof.

[0034] Preferably, the emulsifier comprises a compound of emulsifier A and emulsifier B; the emulsifier A comprises any one of Tween 80, Tween 85, Tween 60, Tween 20, C12-C14 fatty alcohol polyoxyethylene ether, fatty alcohol polyoxyethylene ether sodium sulfate, sodium dodecylbenzene sulfonate, alkylphenol polyoxyethylene ether, isomeric tridecyl alcohol polyoxyethylene ether, coconut acid diethanolamide, diethanolamide or ethylenediaminetetraacetic acid, or a combination of at least two thereof; the emulsifier B comprises any one of Span 80, Span 85, Span 60 or Span 20, or a combination of at least two thereof.

[0035] Preferably, the mass ratio of the emulsifier A to the emulsifier B is (1-9):(1-5), for example, 1:1, 3:2, 6:3, 8:4 or 9:5.

[0036] Preferably, the emulsifier comprises a compound of emulsifier A1, emulsifier A2 and emulsifier B; the emulsifier A1 comprises any one of Tween 80, Tween 85, Tween 60 or Tween 20, or a combination of at least two of them; the emulsifier A2 comprises any one of C12-C14 fatty alcohol polyoxyethylene ether, fatty alcohol polyoxyethylene ether sodium sulfate, sodium dodecylbenzene sulfonate, alkylphenol polyoxyethylene ether, isomeric tridecyl alcohol polyoxyethylene ether, coconut acid diethanolamide, diethanolamide or ethylenediaminetetraacetic acid, or a combination of at least two of them; the emulsifier B comprises any one of Span 80, Span 85, Span 60 or Span 20, or a combination of at least two of them.

[0037] Preferably, the mass ratio of emulsifier A1, emulsifier A2 and emulsifier B is (1-8):(1-8):(1-5), for example, 1:1:1, 3:4:2, 4:5:3, 5:4:4, 7:8:5 or 8:7:5, etc.

[0038] Preferably, the amine chain extender includes any one of ethylenediamine, propylenediamine, hydrazine hydrate, ethanolamine, diethanolamine, N-hydroxyethylethylenediamine, diethylenetriamine, triethylenetetramine, amino-terminated polyether or piperazine, or a combination of at least two thereof.

[0039] Preferably, the aminosilane coupling agent includes any one or a combination of at least two of anilinomethyltriethoxysilane, aminopropyltriethoxysilane, N-(β-aminoethyl-γ-aminopropyl)methyldimethoxysilane, 3-(2,3-epoxypropoxy)propyltrimethoxysilane, N-2-aminoethyl-3-aminopropyltriethoxysilane or bis[3-(triethoxysilyl)propyl]amine.

[0040] Preferably, the raw materials of the solvent-free non-ionic waterborne polyurethane resin further include any one or a combination of at least two of a small molecule alcohol chain extender, an antioxidant, a catalyst or water.

[0041] Preferably, the content of the small molecule alcohol chain extender in the raw material of the solvent-free nonionic waterborne polyurethane resin is 1 to 10 parts by weight, for example, 1 part by weight, 2 parts by weight, 4 parts by weight, 6 parts by weight, 8 parts by weight or 10 parts by weight.

[0042] Preferably, the small molecule alcohol chain extender includes any one of ethylene glycol, propylene glycol, 1,4-butanediol, 1,3-propanediol, neopentyl glycol, hexanediol or 3-methyl-1,5-pentanediol, or a combination of at least two thereof.

[0043] Preferably, the content of antioxidant in the raw material of the solvent-free nonionic waterborne polyurethane resin is 0.2-0.8 parts by weight, for example, 0.2 parts by weight, 0.3 parts by weight, 0.4 parts by weight, 0.5 parts by weight, 0.6 parts by weight, 0.7 parts by weight or 0.8 parts by weight.

[0044] For example, the antioxidant may be antioxidant 1010 purchased from Double Bond Chemical Co., Ltd., Taiwan, China.

[0045] Preferably, the content of the catalyst in the raw material of the solvent-free nonionic waterborne polyurethane resin is 0.1 to 0.2 parts by weight, for example, 0.1 parts by weight, 0.13 parts by weight, 0.16 parts by weight, 0.18 parts by weight, 0.19 parts by weight or 0.2 parts by weight.

[0046] Exemplarily, the catalyst may be selected from BICAT 8118 from a leading American chemical company.

[0047] In a second aspect, the present invention provides a method for preparing the solvent-free nonionic waterborne polyurethane resin as described in the first aspect, the preparation method comprising the following steps:

[0048] The polymer polyol and the optional antioxidant are mixed, and after dehydration, isocyanate and optional part of the catalyst are added to react, and after the NCO content of the system meets the theoretical requirements, non-ionic hydrophilic polyol, optional small molecule alcohol chain extender and optional remaining catalyst are added to carry out chain extension reaction, and after the NCO content of the system meets the theoretical requirements, the temperature is lowered, and then an emulsifier is added to mix, and then water is added to mix, and finally an aminosilane coupling agent and an amine chain extender are added to mix, and after aging, the solvent-free non-ionic waterborne polyurethane resin is obtained.

[0049] Preferably, the preparation method comprises the following steps:

[0050] First, the polymer polyol and the optional antioxidant are mixed, the temperature is raised to 90-120° C. (for example, 90° C., 100° C., 110° C. or 120° C., etc.), and vacuum dehydration is performed for 20-40 min (for example, 20 min, 25 min, 30 min, 35 min or 40 min, etc.), and when the water content of the system is less than 300 ppm (for example, 300 ppm, 280 ppm, 260 ppm, 240 ppm, 200 ppm, 100 ppm or 50 ppm, etc.), the temperature is lowered to 50-60° C. (for example, 50° C., 52° C., 54° C., 56° C., 58° C. or 60° C., etc.); isocyanate and optionally part of the catalyst are added, and the reaction is carried out at 85-90° C. (for example, 85° C., 86° C., 87° C., 88° C., 89° C. or 90° C., etc.) and normal pressure for 2-3 h (for example, 2 h, 2.2h, 2.4h, 2.6h, 2.8h or 3h, etc.), until the NCO content of the system meets the theoretical requirements; then add nonionic hydrophilic polyol, optionally a small molecule alcohol chain extender and optionally the remaining catalyst, and reduce the temperature at 85-90°C (for example, 85°C, 86°C, 87°C, 88°C, 89°C or 90°C) for chain extension reaction for 1-3h (for example, 1h, 1.2h, 1.4h, 1.5h, 2h, 2.5h or 3h, etc.), until the NCO content meets the theoretical requirements; cool to 30-80°C (for example, 30°C, 40°C, 60°C, 70°C or 80°C, etc.), add an emulsifier for mixing, and then add water for mixing; finally, add an aminosilane coupling agent and an amine chain extender for reaction, and after aging, obtain the solvent-free nonionic waterborne polyurethane resin.

[0051] Preferably, before adding the emulsifier for mixing, a step of adding part of the aminosilane coupling agent for mixing is also included, and the remaining part of the aminosilane coupling agent and the amine chain extender can be added at the same time.

[0052] In a third aspect, the present invention provides a water-based microfiber leather, which is obtained by impregnating a fiber non-woven fabric with the solvent-free non-ionic water-based polyurethane resin as described in the first aspect.

[0053] Compared with the prior art, the present invention has the following beneficial effects:

[0054] (1) The present invention uses nonionic hydrophilic polyol as an internal hydrophilic chain extender and an external emulsifier for synergistic emulsification to prepare a solvent-free nonionic waterborne polyurethane resin having the characteristics of small emulsion particle size and good storage stability, thereby solving the problem that a large amount of acetone needs to be introduced into the emulsion synthesized by the conventional method, and truly realizing green and environmentally friendly production;

[0055] (2) The present invention uses nonionic hydrophilic polyol as a hydrophilic nonionic chain extender, so that the obtained solvent-free nonionic waterborne polyurethane resin has no charge, so it is insensitive to various environmental factors such as acid, alkali and electrolyte, and will not cause demulsification due to the addition of various additives, and has a wider range of applications;

[0056] (3) The solvent-free nonionic waterborne polyurethane resin provided by the present invention has excellent properties such as good elasticity, yellowing resistance, aging resistance, solvent resistance, low temperature resistance, tortuosity resistance, and good permeability by introducing an amine chain extender and an aminosilane coupling agent through post-chain extension;

[0057] (4) The solvent-free nonionic water-based polyurethane resin provided by the present invention can play a good role in wetting and protecting, bonding and bundling in the processing of ultrafine fibers. It does not change color at high temperatures in light-colored products, can effectively prevent the accumulation of static charges on the surface of ultrafine fibers, and can enable the fibers to obtain good compatibility with the substrate and interfacial chemical bonding or chemical adsorption and other properties. DETAILED DESCRIPTION

[0058] The technical solution of the present invention is further described below by specific implementation methods. It should be understood by those skilled in the art that the embodiments are only to help understand the present invention and should not be regarded as specific limitations of the present invention.

[0059] Example 1

[0060] A solvent-free non-ionic waterborne polyurethane resin, the components and amounts of which are contained in the raw materials are shown in Table 1 below:

[0061] Table 1

[0062]

[0063] The method for preparing the solvent-free nonionic waterborne polyurethane resin provided in Example 1 comprises the following steps:

[0064] 1) Add the polymer polyol into a reaction kettle and stir evenly, heat to 100°C, dehydrate under a vacuum of -0.1MPa for 30 minutes, wait until the water content of the system is less than 300ppm, cool to 50°C for standby use;

[0065] 2) Add diisocyanate and 50% of the total catalyst into a reactor, strictly control the reaction temperature to 85°C, react for 2.5 hours under normal pressure, take a sample to measure the NCO content, and when the NCO content is lower than 5.84%, proceed to the next step of reaction;

[0066] 3) Add polyethylene oxide ether glycol and the remaining 50% of the catalyst and stir evenly, keep the temperature at 85°C for chain extension reaction for 2 hours, stop heating when the NCO content drops below 4.99%, cool to 65°C for standby use;

[0067] 4) Mix the emulsifier and 100g water, heat to 50°C and stir evenly, and after it is completely melted, obtain an emulsifier aqueous solution, cool to 25°C and set aside;

[0068] Mix the amine chain extender and 100g of water, stir evenly, and after it is completely melted, obtain an amine chain extender aqueous solution for later use;

[0069] 5) adding the emulsifier aqueous solution to the reactor, stirring for 20 seconds, and then adding the remaining water for high-speed emulsification. After the emulsification is completed, slowly adding the aminosilane coupling agent and stirring evenly, and then adding the amine chain extender aqueous solution to react for 30 minutes, and aging at 50° C. for 12 hours to obtain the solvent-free non-ionic waterborne polyurethane resin with a solid content of 40%.

[0070] Example 2

[0071] A solvent-free non-ionic waterborne polyurethane resin, the components and amounts of which are contained in the raw materials are shown in Table 2 below:

[0072] Table 2

[0073]

[0074]

[0075] The preparation method of the solvent-free nonionic waterborne polyurethane resin provided in Example 2 comprises the following steps:

[0076] 1) Add the polymer polyol into a reaction kettle and stir evenly, heat to 110°C, dehydrate under a vacuum of -0.1MPa for 30 minutes, wait until the water content of the system is less than 300ppm, cool to 60°C for standby use;

[0077] 2) Add diisocyanate and 50% of the total catalyst into a reactor, strictly control the reaction temperature to 90°C, react for 2.5 hours under normal pressure, take a sample to measure the NCO content, and when the NCO content is lower than 5.74%, proceed to the next step of reaction;

[0078] 3) Add nonionic hydrophilic polyol, small molecule alcohol chain extender and the remaining 50% of the catalyst and stir evenly, keep warm at 90°C for chain extension reaction for 2 hours, stop heating when the NCO content drops below 4.18%, cool to 65°C and set aside;

[0079] 4) Mix the emulsifier and 100g water, heat to 50°C and stir evenly, and after it is completely melted, obtain an emulsifier aqueous solution, cool to 25°C and set aside;

[0080] Mix the amine chain extender and 100g of water, stir evenly, and after it is completely melted, obtain an amine chain extender aqueous solution for later use;

[0081] 5) adding the emulsifier aqueous solution to the reactor and stirring for 20 seconds, adding the remaining water for high-speed emulsification, and after the emulsification is completed, slowly adding the aminosilane coupling agent and stirring evenly, then adding the amine chain extender aqueous solution to react for 30 minutes, and aging at 50° C. for 12 hours to obtain the solvent-free non-ionic waterborne polyurethane resin with a solid content of 40%.

[0082] Example 3

[0083] A solvent-free nonionic waterborne polyurethane resin, the components and amounts of which are contained in the raw materials are shown in Table 3 below:

[0084] Table 3

[0085]

[0086] The preparation method of the solvent-free nonionic waterborne polyurethane resin provided in Example 3 comprises the following steps:

[0087] 1) Add the polymer polyol into a reaction kettle and stir evenly, raise the temperature to 90°C, dehydrate under a vacuum of -0.1MPa for 30 minutes, wait until the water content of the system is less than 300ppm, cool down to 50°C, and set aside;

[0088] 2) Add diisocyanate and 50% of the total catalyst into a reactor, strictly control the reaction temperature to 85°C, react for 3 hours under normal pressure, take samples to measure the NCO content, and when the NCO content is lower than 7.57%, proceed to the next step of reaction;

[0089] 3) Add nonionic hydrophilic polyol, small molecule alcohol chain extender and the remaining 50% of the catalyst and stir evenly, keep the temperature at 85°C for chain extension reaction for 2 hours, stop heating when the NCO content drops below 5.68%, cool to 65°C and set aside;

[0090] 4) Mix the emulsifier and 100g water, heat to 50°C and stir evenly, and after it is completely melted, obtain an emulsifier aqueous solution, cool to 25°C and set aside;

[0091] Mix the amine chain extender and 100g of water, stir evenly, and after it is completely melted, obtain an amine chain extender aqueous solution for later use;

[0092] 5) adding the emulsifier aqueous solution to the reactor and stirring for 20 seconds, adding the remaining water for high-speed emulsification, and after the emulsification is completed, slowly adding the aminosilane coupling agent and stirring evenly, then adding the amine chain extender aqueous solution to react for 30 minutes, and aging at 50° C. for 12 hours to obtain the solvent-free non-ionic waterborne polyurethane resin with a solid content of 40%.

[0093] Example 4

[0094] A solvent-free non-ionic waterborne polyurethane resin, the components and amounts of which are contained in the raw materials are shown in Table 4 below:

[0095] Table 4

[0096]

[0097] The method for preparing the solvent-free nonionic waterborne polyurethane resin provided in Example 4 comprises the following steps:

[0098] 1) Add the polymer polyol into a reaction kettle and stir evenly, raise the temperature to 90°C, dehydrate under a vacuum of -0.1MPa for 30 minutes, wait until the water content of the system is less than 300ppm, cool down to 50°C, and set aside;

[0099] 2) Add diisocyanate and 50% of the total catalyst into a reactor, strictly control the reaction temperature to 85°C, react for 3 hours under normal pressure, take samples to measure the NCO content, and when the NCO content is lower than 7.44%, proceed to the next step of reaction;

[0100] 3) Add nonionic hydrophilic polyol and the remaining 50% of the catalyst and stir evenly, keep warm at 85°C for chain extension reaction for 2 hours, stop heating when the NCO content drops below 6.49%, cool to 75°C and set aside;

[0101] 4) Mix the emulsifier and 100g water, heat to 50°C and stir evenly, and after it is completely melted, obtain an emulsifier aqueous solution, cool to 25°C and set aside;

[0102] Mix the amine chain extender and 100g of water, stir evenly, and after it is completely melted, obtain an amine chain extender aqueous solution for later use;

[0103] 5) adding the emulsifier aqueous solution to the reactor and stirring for 20 seconds, adding the remaining water for high-speed emulsification, and after the emulsification is completed, slowly adding the aminosilane coupling agent and stirring evenly, then adding the amine chain extender aqueous solution to react for 30 minutes, and aging at 50° C. for 12 hours to obtain the solvent-free non-ionic waterborne polyurethane resin with a solid content of 40%.

[0104] Example 5

[0105] A solvent-free nonionic waterborne polyurethane resin, the components and amounts of which are contained in the raw materials are shown in Table 5 below:

[0106] Table 5

[0107]

[0108]

[0109] The method for preparing the solvent-free nonionic waterborne polyurethane resin provided in Example 5 comprises the following steps:

[0110] 1) Add the polymer polyol into a reaction kettle and stir evenly, raise the temperature to 90°C, dehydrate under a vacuum of -0.1MPa for 30 minutes, wait until the water content of the system is less than 300ppm, cool down to 50°C for use;

[0111] 2) Add diisocyanate and 50% of the total catalyst into a reactor, strictly control the reaction temperature to 85°C, react for 3 hours under normal pressure, take samples to measure the NCO content, and when the NCO content is lower than 5.09%, proceed to the next step of reaction;

[0112] 3) Add nonionic hydrophilic polyol, small molecule alcohol chain extender and the remaining 50% of the catalyst and stir evenly, keep warm at 85°C for 2 hours to extend the chain, stop heating when the NCO content drops below 4.27%, cool to 65°C, add aminopropyltriethoxysilane, react for 30 minutes and set aside;

[0113] 4) Mix the emulsifier and 100g water, heat to 50°C and stir evenly, and after it is completely melted, obtain an emulsifier aqueous solution, cool to 25°C for use;

[0114] Mix the amine chain extender and 100g of water, stir evenly, and after it is completely melted, obtain an amine chain extender aqueous solution for later use;

[0115] 5) adding the emulsifier aqueous solution to the reactor and stirring for 20 seconds, adding the remaining water for high-speed emulsification, and after the emulsification is completed, slowly adding N-(β-aminoethyl-γ-aminopropyl)methyldimethoxysilane and stirring evenly, then adding the amine chain extender aqueous solution to react for 30 minutes, and aging at 50° C. for 12 hours to obtain the solvent-free non-ionic waterborne polyurethane resin with a solid content of 40%.

[0116] Example 6

[0117] A solvent-free non-ionic waterborne polyurethane resin, the components and amounts of which are contained in the raw materials are shown in Table 6 below:

[0118] Table 6

[0119]

[0120] The preparation method of the solvent-free non-ionic waterborne polyurethane resin provided in Example 6 refers to Example 2.

[0121] Example 7

[0122] A solvent-free nonionic waterborne polyurethane resin, the components and amounts of which are contained in the raw materials are shown in Table 7 below:

[0123] Table 7

[0124]

[0125] The preparation method of the solvent-free non-ionic waterborne polyurethane resin provided in Example 7 refers to Example 2.

[0126] Example 8

[0127] A solvent-free non-ionic water-based polyurethane resin, the components and amounts of which are contained in the raw materials are shown in Table 8 below:

[0128] Table 8

[0129]

[0130]

[0131] The preparation method of the solvent-free non-ionic waterborne polyurethane resin provided in Example 8 refers to Example 5.

[0132] Example 9

[0133] A solvent-free non-ionic waterborne polyurethane resin is disclosed, which differs from Example 3 only in that no small molecule alcohol chain extender is added, and other components, amounts and preparation methods are all the same as those of Example 3.

[0134] Comparative Example 1

[0135] A solvent-free nonionic waterborne polyurethane resin is disclosed. The difference between the invention and the first embodiment is that the polyethylene oxide ether glycol (molecular weight 1000) is replaced by polypropylene oxide ether glycol (molecular weight 1000). The other components, dosages and preparation methods are the same as those of the third embodiment.

[0136] Comparative Example 2

[0137] A solvent-free non-ionic water-based polyurethane resin is disclosed. The difference between the above-mentioned embodiment 1 is that no emulsifier is added, and the amount of water added is 827 grams. The other components, amounts and preparation methods are all the same as those of the embodiment 1.

[0138] Comparative Example 3

[0139] A solvent-free nonionic waterborne polyurethane resin is disclosed. The difference between the solvent-free nonionic waterborne polyurethane resin and the embodiment 1 is that no aminosilane coupling agent is added, and other components, dosages and preparation methods are all the same as those of the embodiment 1.

[0140] Comparative Example 4

[0141] A solvent-free non-ionic waterborne polyurethane resin is disclosed. The difference between the solvent-free non-ionic waterborne polyurethane resin and the embodiment 1 is that the non-ionic hydrophilic polyol is not added, and the other components, dosages and preparation methods are all the same as those of the embodiment 1.

[0142] Comparative Example 5

[0143] A solvent-free nonionic waterborne polyurethane resin is disclosed. The difference between the solvent-free nonionic waterborne polyurethane resin and the embodiment 1 is that no amine chain extender is added, and other components, dosages and preparation methods are all the same as those of the embodiment 1.

[0144] Comparative Example 6

[0145] A solvent-free non-ionic water-based polyurethane resin, specifically the acetone process resin JF-PDY-823HY produced by Huafeng Company.

[0146] Application Example 1

[0147] A water-based microfiber leather, the preparation method of which comprises the following steps:

[0148] 1) Take 100 parts by weight of the solvent-free nonionic waterborne polyurethane resin provided in Example 1, add 0.4 parts by weight of a thickener (purchased from Dow Chemical, brand ACRYSOL TM RM-2020NPR), so that the viscosity of the solution is 1000cps / 25°C, and a working slurry is obtained;

[0149] 2) The obtained working pulp is then used to impregnate the water-soluble sea island fiber non-woven fabric, and then dried in an oven at 125°C for 30 minutes. After taking it out, it is placed in 100°C boiling water for weight reduction treatment for 30 minutes to obtain a leather sample, and then the leather sample is taken out for water washing and drying to obtain the water-based microfiber leather.

[0150] Application Examples 2 to 9 and Comparative Application Examples 1 to 6

[0151] Application Examples 2 to 9 and Comparative Application Examples 1 to 6 respectively provide a water-based microfiber leather, which differs from Application Example 1 in that the solvent-free non-ionic water-based polyurethane resin provided by Examples 2 to 9 and Comparative Examples 1 to 6 is used to replace the solvent-free non-ionic water-based polyurethane resin provided by Example 1, and other materials and preparation methods are the same as those in Application Example 1.

[0152] Performance test of polyurethane resin:

[0153] (1) Appearance: Visual observation.

[0154] (2) Stability: After storage at room temperature for 6 months, the appearance was visually observed.

[0155] (3) Water absorption rate: Add thickener to each solvent-free non-ionic waterborne polyurethane resin so that the viscosity of the solution is 2500cps / 25°C to obtain a working slurry; apply the working slurry on a glass plate and dry it, cut the dried film into a size of 30×30mm, weigh the initial weight M1, and then place it in 90°C hot water for 30 minutes, take out and wipe off the surface water, weigh the weight M2, and calculate the water absorption rate = (M2-M1) / M1×100%.

[0156] (4) Particle size and particle size distribution: The particle size was tested using a Malvern particle size tester.

[0157] The resins provided in Examples 1 to 9 and Comparative Examples 1 to 6 were tested according to the above test method. The test results are shown in Table 9:

[0158] Table 9

[0159] Appearance stability Water absorption / % Particle size / nm Particle size distribution Example 1 Blue light, milky white liquid No stratification, no settlement 3.3 169.4 0.124 Example 2 Blue light, milky white liquid No stratification, no settlement 4.3 182.1 0.113 Example 3 Blue light, milky white liquid No stratification, no settlement 2.6 131.2 0.125 Example 4 Blue light, milky white liquid No stratification, no settlement 3.7 143.2 0.152 Example 5 Blue light, milky white liquid No stratification, no settlement 2.9 168.3 0.147 Example 6 Blue light, milky white liquid No stratification, no settlement 3.3 152.9 0.132 Example 7 Blue light, milky white liquid No stratification, no settlement 3.3 162.3 0.129 Example 8 Blue light, milky white liquid No stratification, no settlement 3.3 146.1 0.142 Example 9 Blue light, milky white liquid No stratification, no settlement 4.1 152.1 0.159 Comparative Example 1 Milky white liquid with residue Stratification, with sedimentation 3.3 623.1 0.862 Comparative Example 2 Milky white liquid with residue Stratification, with sedimentation 3.3 890.2 0.843 Comparative Example 3 Blue light, milky white liquid No stratification, no settlement 4.5 171.2 0.132 Comparative Example 4 Milky white liquid with residue Stratification, with sedimentation 3.1 642.1 0.912 Comparative Example 5 Blue light, milky white liquid Demulsification, sedimentation - 1320.4 0927 Comparative Example 6 Blue light, milky white liquid No stratification, no settlement 14.1 90.6 0.123

[0160] Among them, “-” means that demulsification occurred and the test could not be carried out.

[0161] From the data in Table 9, we can see that:

[0162] The solvent-free nonionic waterborne polyurethane resin provided in Examples 1 to 8 is prepared by combining a nonionic internal hydrophilic chain extender and an external emulsifier for synergistic emulsification, and the emulsion particle size of the nonionic waterborne polyurethane resin is small, the storage stability is good, the film-forming property is excellent, and the water absorption rate of the film after drying is less than 4.5%;

[0163] However, the solvent-free nonionic waterborne polyurethane resins provided in Comparative Examples 1 to 2 and 4 will delaminate and settle after being stored at room temperature for 6 months, and their stability is poor.

[0164] The solvent-free nonionic waterborne polyurethane resins provided in Comparative Examples 3 and 6 have a high water absorption rate after drying of the adhesive film;

[0165] The solvent-free nonionic waterborne polyurethane resin provided in Comparative Example 5 was demulsified and could not form a film, and the water absorption rate could not be tested.

[0166] Performance test of water-reduced microfiber leather:

[0167] (1) Microfiber feel, appearance, and creases: visual observation and touch.

[0168] (2) Alkali resistance: Cut the water-based microfiber leather sample into a size of 30×30 mm, weigh the initial weight M1, then place it in a 90°C, 10% NaOH solution for 4 h, take it out and dry it at 140°C, weigh the weight M2, calculate the natron weight loss rate = (M1-M2) / M1×00%, and observe it visually and touch it again.

[0169] (3) Resistance to jungle aging: Place the prepared water-based microfiber leather sample in a constant temperature and humidity machine, set the temperature to 70°C and the humidity to 95%, leave it for 5 weeks, and observe the morphology of the microfiber leather.

[0170] According to the above test method, the water-based microfiber leather provided by Examples 1 to 9 and Comparative Application Examples 1 to 6 was tested, and the test results are shown in Table 10:

[0171] Table 10

[0172]

[0173]

[0174] “-” means that the test cannot be performed.

[0175] From the data in Table 10, we can see that:

[0176] The water-based microfiber leather provided in Application Examples 1 to 9 has good hand feel, fine creases, good rebound, and normal jungle tests;

[0177] However, the water-based microfiber leather provided in comparative application examples 1-2 and 4-5 is completely unusable;

[0178] The water-based microfiber leather provided in comparative application examples 3 and 6 has a poor hand feel, rough creases, poor rebound, and severe stickiness after the jungle test.

[0179] The applicant declares that the present invention illustrates a solvent-free nonionic waterborne polyurethane resin and its preparation method and application through the above embodiments, but the present invention is not limited to the above embodiments, that is, it does not mean that the present invention must rely on the above embodiments to be implemented. Those skilled in the art should understand that any improvement of the present invention, equivalent replacement of various raw materials of the product of the present invention, addition of auxiliary components, selection of specific methods, etc., all fall within the protection scope and disclosure scope of the present invention.

Claims

1. A solvent-free nonionic waterborne polyurethane resin, characterized in that: The raw materials of the solvent-free non-ionic waterborne polyurethane resin include polymer polyol, diisocyanate, non-ionic hydrophilic polyol, emulsifier, amine chain extender and aminosilane coupling agent.

2. The solvent-free nonionic waterborne polyurethane resin according to claim 1, characterized in that: The raw materials of the solvent-free non-ionic waterborne polyurethane resin include the following components in parts by weight:

3. The solvent-free nonionic waterborne polyurethane resin according to claim 1 or 2, characterized in that: The number average molecular weight of the polymer polyol is 500 to 8000; Preferably, the polymer polyol comprises polyester polyol and / or polyether polyol; Preferably, the polyether polyol comprises any one or a combination of at least two of polytetramethylene oxide ether diol, polypropylene oxide ether diol, polypropylene oxide ether triol, polypropylene oxide / ethylene oxide ether diol or polypropylene oxide / ethylene oxide ether triol; Preferably, the polyester polyol includes any one or a combination of at least two of polycarbonate diol, polycaprolactone diol, polyneopentyl adipate diol, polyhexane adipate diol or polybutylene adipate diol; Preferably, the isocyanate includes any one of 1,6-hexamethylene diisocyanate, isophorone diisocyanate, diphenylmethane-4,4-diisocyanate, dicyclohexylmethane diisocyanate, tetramethylxylene diisocyanate or toluene diisocyanate, or a combination of at least two thereof, and is further preferably any one of isophorone diisocyanate, dicyclohexylmethane diisocyanate, toluene diisocyanate, hexamethylene diisocyanate or diphenylmethane-4,4-diisocyanate, or a combination of at least two thereof.

4. The solvent-free nonionic waterborne polyurethane resin according to any one of claims 1 to 3, characterized in that: The number average molecular weight of the nonionic hydrophilic polyol is 500 to 8000; Preferably, the nonionic hydrophilic polyol includes any one of polyethylene oxide ether glycol, polyethylene oxide ether glycol monomethyl ether, polyethylene oxide ether glycol monoethyl ether, polypropylene oxide / ethylene oxide ether glycol monomethyl ether, polypropylene oxide / ethylene oxide ether glycol monoethyl ether or trimethylolpropane polyethoxy monomethyl ether, or a combination of at least two thereof.

5. The solvent-free nonionic waterborne polyurethane resin according to any one of claims 1 to 4, characterized in that: The emulsifier includes any one of Tween 80, Tween 85, Tween 60, Tween 20, Span 80, Span 85, Span 60, Span 20, C12-C14 fatty alcohol polyoxyethylene ether, fatty alcohol polyoxyethylene ether sodium sulfate, sodium dodecylbenzene sulfonate, alkylphenol polyoxyethylene ether, coconut acid diethanolamide, isomeric tridecyl alcohol polyoxyethylene ether, diethanolamide or ethylenediaminetetraacetic acid, or a combination of at least two thereof; Preferably, the emulsifier comprises a compound of emulsifier A and emulsifier B, wherein the emulsifier A comprises any one or a combination of at least two of Tween 80, Tween 85, Tween 60, Tween 20, C12-C14 fatty alcohol polyoxyethylene ether, fatty alcohol polyoxyethylene ether sodium sulfate, sodium dodecylbenzene sulfonate, alkylphenol polyoxyethylene ether, isomeric tridecyl alcohol polyoxyethylene ether, coconut acid diethanolamide, diethanolamide or ethylenediaminetetraacetic acid, and the emulsifier B comprises any one or a combination of at least two of Span 80, Span 85, Span 60 or Span 20; Preferably, the mass ratio of the emulsifier A to the emulsifier B is (1-9):(1-5); Preferably, the emulsifier comprises a compound of emulsifier A1, emulsifier A2 and emulsifier B, the emulsifier A1 comprises any one of Tween 80, Tween 85, Tween 60 or Tween 20 or a combination of at least two thereof, the emulsifier A2 comprises any one of C12-C14 fatty alcohol polyoxyethylene ether, fatty alcohol polyoxyethylene ether sodium sulfate, sodium dodecylbenzene sulfonate, alkylphenol polyoxyethylene ether, isomeric tridecyl alcohol polyoxyethylene ether, coconut acid diethanolamide, diethanolamide or ethylenediaminetetraacetic acid or a combination of at least two thereof, and the emulsifier B comprises any one of Span 80, Span 85, Span 60 or Span 20 or a combination of at least two thereof; Preferably, the mass ratio of the emulsifier A1, emulsifier A2 and emulsifier B is (1-8):(1-8):(1-5).

6. The solvent-free nonionic waterborne polyurethane resin according to any one of claims 1 to 5, characterized in that: The amine chain extender includes any one or a combination of at least two of ethylenediamine, propylenediamine, hydrazine hydrate, ethanolamine, diethanolamine, N-hydroxyethylethylenediamine, diethylenetriamine, triethylenetetramine, amino-terminated polyether or piperazine; Preferably, the aminosilane coupling agent includes any one or a combination of at least two of anilinomethyltriethoxysilane, aminopropyltriethoxysilane, N-(β-aminoethyl-γ-aminopropyl)methyldimethoxysilane, 3-(2,3-epoxypropoxy)propyltrimethoxysilane, N-2-aminoethyl-3-aminopropyltriethoxysilane or bis[3-(triethoxysilyl)propyl]amine.

7. The solvent-free nonionic waterborne polyurethane resin according to any one of claims 1 to 6, characterized in that: The raw materials of the solvent-free non-ionic waterborne polyurethane resin also include any one or a combination of at least two of a small molecule alcohol chain extender, an antioxidant, a catalyst or water; Preferably, the content of the small molecule alcohol chain extender in the raw material of the solvent-free non-ionic waterborne polyurethane resin is 1 to 10 parts by weight; Preferably, the small molecule alcohol chain extender includes any one or a combination of at least two of ethylene glycol, propylene glycol, 1,4-butanediol, 1,3-propanediol, neopentyl glycol, hexanediol or 3-methyl-1,5-pentanediol; Preferably, the content of antioxidant in the raw material of the solvent-free non-ionic waterborne polyurethane resin is 0.2 to 0.8 parts by weight; Preferably, the content of the catalyst in the raw material of the solvent-free non-ionic waterborne polyurethane resin is 0.1 to 0.2 parts by weight.

8. A method for preparing the solvent-free nonionic waterborne polyurethane resin according to any one of claims 1 to 7, characterized in that: The preparation method comprises the following steps: The polymer polyol and the optional antioxidant are mixed, and after dehydration, isocyanate and optional part of the catalyst are added to react, and after the NCO content of the system meets the theoretical requirements, non-ionic hydrophilic polyol, optional small molecule alcohol chain extender and optional remaining catalyst are added to carry out chain extension reaction, and after the NCO content of the system meets the theoretical requirements, the temperature is lowered, and then an emulsifier is added to mix, and then water is added to mix, and finally an aminosilane coupling agent and an amine chain extender are added to mix, and after aging, the solvent-free non-ionic waterborne polyurethane resin is obtained.

9. The preparation method according to claim 8, characterized in that: The preparation method comprises the following steps: First, polymer polyol and optional antioxidant are mixed, heated to 90-120° C., vacuum dehydrated for 20-40 minutes, and when the water content of the system is less than 300 ppm, the temperature is lowered to 50-60° C.; isocyanate and optional part of the catalyst are added, and the reaction is carried out at 85-90° C. under normal pressure for 2-3 hours, and when the NCO content of the system meets the theoretical requirements; nonionic hydrophilic polyol, optional small molecule alcohol chain extender and optional remaining catalyst are added, and the temperature is lowered to 85-90° C. for chain extension reaction for 1-3 hours, and when the NCO content meets the theoretical requirements; the temperature is lowered to 30-80° C., and an emulsifier is added for mixing, and then water is added for mixing; finally, an aminosilane coupling agent and an amine chain extender are added for reaction, and the solvent-free nonionic waterborne polyurethane resin is obtained after aging; Preferably, before adding the emulsifier for mixing, the step of adding part of the aminosilane coupling agent for mixing is also included.

10. A water-based microfiber leather, characterized in that: The water-based microfiber leather is obtained by impregnating fiber non-woven fabric with the solvent-free non-ionic water-based polyurethane resin as described in any one of claims 1 to 7.

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