Micro-crosslinked polyurea polyurethane as well as application method and product thereof

Abstract

The invention provides micro-crosslinked polyurea polyurethane as well as an application method and a product thereof, the micro-crosslinked polyurea polyurethane comprises a first component and a second component, the first component is a polyurea polyurethane base material prepared by carrying out polymerization reaction on diisocyanate, prepolymer dihydric alcohol, a dihydric alcohol chain extender and a diamine chain extender; the second component is a polyisocyanate compound and comprises at least one of an HDI (hexamethylene diisocyanate) tripolymer, a TDI (toluene diisocynate) tripolymer, an IPDI (isophorone diisocyanate) tripolymer and triphenylmethane triisocyanate; the first component and the second component are uniformly mixed in an organic solvent and then spontaneously subjected to micro-crosslinking / self-curing reaction to form micro-crosslinking polyurea polyurethane; and the mass of the second component accounts for 0.5-5% of the mass of the first component. And uniformly mixing the first component and the second component, coating the mixture on the shoe insole subjected to surface treatment within 2 hours, drying, and curing the surface coating to obtain the shoe outsole. The sneaker outsole made of the micro-crosslinked polyurea polyurethane has the characteristics of light weight, high wear resistance and high slip resistance.

Description

Technical Field

[0001] This invention relates to the field of polyurethane technology, and in particular to a micro-crosslinked polyurea polyurethane, its application methods, and products. Background Technology

[0002] Polyurethane (PU) is a polymer material with urethane bonds as its core repeating functional groups, produced by the polymerization reaction of polyols, isocyanates, and chain extenders. PU possesses high strength, high toughness, wear resistance, oil resistance, and ozone resistance, and is widely used in athletic shoe outsoles, providing excellent slip resistance and abrasion resistance. Thermoplastic polyurea polyurethane refers to thermoplastic polyurethane containing urea-formaldehyde bonds in its molecular chain. Compared to general thermoplastic polyurethane, it has higher mechanical strength, wear resistance, and chemical resistance.

[0003] Abrasion resistance is a key parameter for evaluating the function and quality of athletic shoe outsoles. It determines the lifespan and consumer reputation of athletic shoes, making it a hot research and development area for various brands. To meet the same abrasion resistance requirements, significantly improving outsole abrasion resistance allows for thinner outsoles, reducing the weight of the shoe and thus enhancing the athletic experience for consumers and the performance of professional runners. Furthermore, during relatively strenuous activities such as long-distance running, basketball, table tennis, and badminton, or in hot summer weather, the friction between the shoe sole and the ground generates heat in the outsole, with local temperatures reaching 60°C or higher. This also creates a higher demand for heat-resistant outsole materials.

[0004] US Patent 2020 / 0115489 A1 discloses a coated article comprising intumescent thermoplastic polyurethane. The polyurethane urea solution used to prepare the coating can be applied to a substrate by brushing, spraying, roller coating, slot coating, dip coating, and / or printing to form a protective coating. The polyurethane urea in this technology contains polycarbonate structural units (using polycarbonate diol as the polyol), which improves the adhesion of the polyurethane urea coating to the intumescent TPU surface and provides sufficient flexibility to maintain high bond strength even when the intumescent TPU is bent. While this technology indicates its applicability to shoe soles, its functionality is more decorative, and it does not focus on the coating's abrasion resistance, let alone its thermal abrasion resistance.

[0005] Patent application CN 111356713A discloses a method for forming an elastomer polyurethane product with good wear resistance. The preparation process involves separately preparing isocyanate and isocyanate reactive components, then adding a thixotropic agent to directly generate the polyurethane product through an exothermic / self-curing reaction (coating on a carrier must be completed before complete curing). This exothermic reaction is quite vigorous, generating high temperatures, exceeding 100°C. If coated on a low-density shoe midsole within a suitable viscosity range (i.e., when the carrier matrix is ​​low-density foamed shoe material), the high reaction temperature can cause wrinkles and localized shrinkage on the surface of the low-density shoe material, limiting its use on low-density soles and hindering the overall lightweighting of the shoe. Furthermore, the direct and vigorous reaction between the isocyanate and isocyanate reactive components is also detrimental to the control of crosslinking degree. The final product often has a high degree of crosslinking, resulting in good wear resistance but poor damping and slip resistance.

[0006] Therefore, a coatable thermoplastic polyurethane material that combines abrasion resistance and slip resistance is provided; it can be used for coating low-density shoe midsoles, and it can also give the soles better thermal abrasion resistance (reducing wear and tear on the soles during strenuous exercise and increasing service life) and slip resistance, which is of practical significance and helps to improve the sports experience of ultralight sports shoes. Summary of the Invention

[0007] To address the problems of poor heat abrasion resistance and difficulty in achieving both abrasion resistance and slip resistance in existing coated polyurethane shoe soles, this invention provides a micro-crosslinked polyurea polyurethane, its application method, and the product thereof. The outsole made of this micro-crosslinked polyurea polyurethane exhibits lightweight, thinness, high abrasion resistance / high heat abrasion resistance, and high slip resistance, greatly improving the wearing comfort and athletic experience of running shoes.

[0008] The technical solution of the present invention is as follows: A micro-crosslinked polyurea polyurethane includes a first component and a second component. The first component is a polyurea polyurethane base material prepared by polymerization reaction of diisocyanate, prepolymer diol, diol chain extender and diamine chain extender. The second component is a polyisocyanate compound, including at least one of HDI trimer, TDI trimer, IPDI trimer and triphenylmethane triisocyanate. The first and second components are mixed evenly in an organic solvent to form a mixed solution, and a micro-crosslinking / self-curing reaction spontaneously occurs in the solution to form micro-crosslinked polyurea polyurethane; the mass ratio of the second component is 0.5~5% of the mass of the first component.

[0009] Furthermore, the organic solvent is at least one selected from N,N-dimethylformamide, N,N-dimethylacetamide, tetrahydrofuran, pyridine, and carbon tetrachloride.

[0010] Furthermore, the solid content of the mixed solution is controlled within 5-30% to facilitate coating on the carrier and curing to form micro-crosslinked polyurea polyurethane.

[0011] Furthermore, the diisocyanate may be an aromatic diisocyanate or an aliphatic diisocyanate. The aromatic diisocyanate includes at least one of methylene diphenyl diisocyanate, toluene diisocyanate, terephthalic diisocyanate, and diphenylmethylene diisocyanate; the aliphatic diisocyanate includes at least one of hexamethylene diisocyanate, methylene dicyclohexyl diisocyanate, isophorone diisocyanate, and cyclohexane dimethylene diisocyanate.

[0012] Furthermore, the diol prepolymer is at least one of polyethylene adipate, propylene adipate, butylene adipate, poly(ε-caprolactone diol), polycarbonate diol, polyethylene oxide homopolymer diol, polypropylene oxide homopolymer diol, and polytetrahydrofuran ether diol.

[0013] Furthermore, the diol chain extender is at least one selected from ethylene glycol, 1,3-propanediol, 1,4-butanediol, 1,5-pentanediol, and 1,6-hexanediol.

[0014] Furthermore, the diamine chain extender is at least one selected from ethylenediamine, butanediamine, hexamethylenediamine, isophoronediamine, 3,5-dimethylthiotoluenediamine, diethyltoluenediamine, 1,3-propanediol bis(4-aminobenzoate), 4,4'-methylenebis(2-ethyl)aniline, and bis-sec-butylaminodiphenylmethane.

[0015] Furthermore, the molar ratio of diisocyanate, diol prepolymer, and diol / amine chain extender is 10:2~8:8~2, that is, the molar amount of diisocyanate is the sum of the molar amounts of diol prepolymer and diol / amine chain extender, wherein the molar ratio of diol prepolymer to diol / amine chain extender is between 1:4 and 4:1; and the molar ratio of diol chain extender to diamine chain extender is between 3:1 and 1:3.

[0016] This invention also provides a method for applying the above-mentioned micro-crosslinked polyurea polyurethane, comprising the following steps: S1. Weigh out diisocyanate, prepolymer diol, diol chain extender and diamine chain extender according to the proportion, and prepare the first component by polymerization reaction. After drying, store for later use. S2. Treat the shoe midsole surface with cleaning agent and surfactant in sequence, and ensure that the next step is carried out within 12 hours; S3. Dissolve the first component in an organic solvent. After it is completely dissolved, add the second component and mix it evenly. Apply it to the shoe midsole that has undergone surface treatment in step S2 within 2 hours. S4. Place the coated shoe midsole in an oven and wait for the surface coating to cure before transferring it to a ventilated area until the solvent has completely evaporated, thus completing the shoe outsole production.

[0017] A footwear product, wherein the outsole is made by the above-described method of applying micro-crosslinked polyurea polyurethane.

[0018] The advantages of this invention are as follows: the micro-crosslinked polyurea polyurethane provided not only contains long-chain polyurea polyurethane blocks, but also uses stable isocyanate trimers as crosslinking points. Strong hydrogen bonds are formed between the polyurea groups of the long-chain polyurea polyurethane blocks, which gives the polymer extremely high strength, toughness and damping properties. At the same time, the wear resistance of the material, especially the thermal wear resistance, is significantly increased.

[0019] Meanwhile, the crosslinking points of isocyanate trimer or triisocyanate are relatively limited, which makes the exothermic reaction between the first and second components more moderate, presenting a slow micro-crosslinking reaction state. This is not only more conducive to controlling the overall degree of crosslinking of the polymer, but also allows it to remain in a liquid state for a longer time, making it easier to carry out operations such as spraying, brushing, roller coating, dip coating or screen printing. Even when coated on low-density foam shoe midsoles, it will not cause secondary reactions with low-density foam shoe materials due to overheating, and it is more conducive to combining with lightweight midsoles.

[0020] Therefore, the outsoles of sports shoes made using this micro-crosslinked polyurea polyurethane material can exhibit lightweight, high wear resistance, and high slip resistance, greatly improving the wearing comfort and sports experience of running shoes. Detailed Implementation

[0021] To make the objectives, technical solutions, and advantages of this invention clearer, the technical solutions of this invention will be clearly and completely described below in conjunction with specific embodiments of this invention. All other embodiments obtained by those skilled in the art based on the embodiments of this invention without creative effort are within the scope of protection of this invention.

[0022] This invention provides a micro-crosslinked polyurea polyurethane, comprising a first component and a second component, which are two-component systems. Before use, the first and second components are dissolved in an organic solvent in a certain proportion, and crosslinking and curing are completed by evaporating part of the solvent at room temperature or by heating. After mixing the first and second components, the mixture is applied to the shoe midsole substrate within a certain viscosity range by spraying, brushing, roller coating, dip coating, or screen printing to form a continuous or pre-patterned thin film, which can be used as an outsole for sports shoes.

[0023] The first component is a polyurea polyurethane base material prepared by polymerization reaction of diisocyanate, prepolymer diol, diol chain extender and diamine chain extender.

[0024] The diisocyanate may be an aromatic diisocyanate or an aliphatic diisocyanate. The aromatic diisocyanate includes at least one of methylene diphenyl diisocyanate (MDI), toluene diisocyanate (TDI), terephthalic diisocyanate (PPDI), and diphenylmethylene diisocyanate (XDI). The aliphatic diisocyanate includes at least one of hexamethylene diisocyanate (HDI), methylene dicyclohexyl diisocyanate (HMDI), isophorone diisocyanate (IPDI), and cyclohexane diisocyanate (HXDI). Isophorone diisocyanate (IPDI) is preferred.

[0025] The diol prepolymer is at least one selected from polyethylene adipate, propylene adipate, butylene adipate, poly(ε-caprolactone) diol, polycarbonate diol, polyethylene oxide homopolymer ether diol, polypropylene oxide homopolymer ether diol, and polytetrahydrofuran ether diol; preferably at least one selected from poly(ε-caprolactone) diol and polycarbonate diol. The average molecular weight of the diol prepolymer is preferably 2000-3000.

[0026] The diol chain extender is at least one selected from ethylene glycol, 1,3-propanediol, 1,4-butanediol, 1,5-pentanediol, and 1,6-hexanediol.

[0027] The diamine chain extender is at least one of ethylenediamine (EDA), butanediamine (BDA), hexamethylenediamine (HDA), isophorone diamine (PDA), 3,5-dimethylthiotoluenediamine (DMTDA, E-300), diethyltoluenediamine (DETDA, E-100), 1,3-propanediol bis(4-aminobenzoate) (740M), 4,4'-methylenebis(2-ethyl)aniline (MOEA), and bis-sec-butylaminodiphenylmethane (MDBA).

[0028] The molar ratio of diisocyanate, diol prepolymer, and diol / amine chain extender is 10:2~8:8~2, meaning the molar amount of diisocyanate is the sum of the molar amounts of diol prepolymer and diol / amine chain extender. The molar ratio of diol prepolymer to diol / amine chain extender is between 1:4 and 4:1, and the molar ratio of diol chain extender to diamine chain extender is between 3:1 and 1:3.

[0029] In the preparation process of the first component, those skilled in the art can add additives such as catalysts, leveling agents, antioxidants, and pigments according to the actual situation in the polymerization reaction or to increase some properties of the final micro-crosslinked elastomer. Since the proportion of additives is very low and does not affect the main structure of the first component, this invention will not elaborate on this.

[0030] The first component reacts with diisocyanate, prepolymer diol, diol chain extender, and diamine chain extender to form a linear molecular structure polyurea polyurethane elastomer base material, whose end-capping groups are still hydroxyl or amino, and can further react with the second component.

[0031] The second component is a polyisocyanate compound, including at least one of HDI trimer, TDI trimer, IPDI trimer, and triphenylmethane triisocyanate (or "triisocyanate"). The second component is mainly used to initiate micro-crosslinking reactions with the first component. The isocyanate groups in the second component can form urethane or urea structures with the hydroxyl or amino groups of the end-capping groups in the first component.

[0032] The mass percentage of the second component is 0.5 to 5% of the mass of the first component, preferably 0.5 to 2%.

[0033] The first and second components are mixed uniformly in an organic solvent to form a mixed solution, in which a micro-crosslinking / self-curing reaction spontaneously occurs. The organic solvent is at least one selected from N,N-dimethylformamide (DMF), N,N-dimethylacetamide (DMAc), tetrahydrofuran (THF), pyridine (Py), and carbon tetrachloride. The solid content of the mixed solution is controlled within 5-30% to facilitate coating, preferably 10-20%, and more preferably 12-15%.

[0034] Since the first component is a long-chain polyurea polyurethane elastomer and the second component is an isocyanate trimer or triisocyanate containing a stable isocyanurate ring or triphenyl, when the first and second components crosslink, a polymer structure of long-chain linear polyurethane blocks can be formed with the molecules of the second component as crosslinking points. This structure not only facilitates the interaction of hydrogen bonds between multiple long-chain linear polyurethane blocks, but also fully forms physical crosslinking points, effectively dissipating external energy, making the overall softness better, exhibiting excellent damping properties, and further improving the dry and wet anti-slip properties of the sole.

[0035] Meanwhile, the limited number of crosslinking points in isocyanate trimers or triisocyanates results in a milder exothermic reaction between the first and second components, exhibiting a slow, micro-crosslinking reaction state. This not only better controls the overall polymer crosslinking degree, with the maximum exothermic temperature not exceeding 60℃ and a complete curing time of over 2 hours, but also allows for a longer liquid state, facilitating better application methods such as spraying, brushing, roller coating, dip coating, or screen printing. Even when coated on low-density foam shoe midsoles, it avoids secondary reactions with the low-density foam material due to overheating, further enhancing its integration with lightweight midsoles. The coated micro-crosslinked polyurea polyurethane elastomer can achieve a low thickness that is difficult to achieve using molding methods, contributing to the lightweighting of athletic shoes.

[0036] Specifically, the processing method of applying micro-crosslinked polyurea polyurethane to the outsole of sports shoes according to the present invention includes the following steps: S1. Weigh out diisocyanate, prepolymer diol, diol chain extender and diamine chain extender according to the above proportions, and prepare the first component (polyurea polyurethane base material) by polymerization reaction. After drying, store for later use.

[0037] S2. Treat the shoe midsole surface with cleaning agent and surfactant in sequence, and ensure that the next step is carried out within 12 hours.

[0038] S3. Take a certain amount of the first component and dissolve it in an organic solvent. After the polyurea polyurethane base material is completely dissolved, add a certain amount of the second component, mix it evenly, and coat it onto the shoe midsole after surface treatment in step S2 within 2 hours.

[0039] S4. Place the coated shoe midsole in an oven and, after the surface coating has cured, transfer it to a ventilated area until the solvent has completely evaporated, completing the outsole production. The coated shoe outsole surface should be dry and free of adhesion.

[0040] The technical effects of the present invention will be further illustrated below through specific embodiments and comparative examples.

[0041] Example 1 A micro-crosslinked polyurea polyurethane shoe sole, wherein the first component comprises the following components in molar proportions: 10 parts methylene diphenyl diisocyanate (MDI), 8 parts polytetrahydrofuran ether diol (molecular weight ~2000), 1.5 parts butanediol, and 0.5 parts hexamethylenediamine; the second component is trimeric diisocyanate, and the mass percentage of the second component is 0.5% of the mass of the first component; the organic solvent is DMF; and the solid content is 5%.

[0042] The outsole processing was completed using the above-described method for applying micro-crosslinked polyurea polyurethane to athletic shoe outsoles, with the coating method being spraying.

[0043] The prepared shoe outsole was tested according to GB / T 9867 "Determination of Abrasion Resistance of Vulcanized Rubber or Thermoplastic Rubber (Rotary Roller Abrasion Test)" and GB / T 3903.6-2017 "Test Methods for Shoe Shoes - Antislip Performance". The hardness was 58A, the layer thickness was 50μm, the SATRA dry antislip was 0.82, the wet antislip was 0.45, and the DIN value at room temperature (25℃) was 25 mm. 3 High temperature (80℃) DIN is 45 mm 3 Yellowing resistance level is 3-4.

[0044] Example 2 A micro-crosslinked polyurea polyurethane shoe sole, wherein the first component comprises the following components in molar proportions: 10 parts hexamethylene diisocyanate (HDI), 7 parts polyethylene adipate diol (molecular weight ~2000), 1.8 parts hexanediol, and 1.2 parts hexamethylenediamine; the second component is trimer TDI, and the mass percentage of the second component is 1.5% of the mass of the first component; the organic solvent is DMF; and the solid content is 15%.

[0045] The outsole processing was completed using the above-described method for applying micro-crosslinked polyurea polyurethane to athletic shoe outsoles, with the coating method being spraying.

[0046] The prepared shoe outsole was tested according to GB / T 9867 "Determination of Abrasion Resistance of Vulcanized Rubber or Thermoplastic Rubber (Rotary Roller Abrasion Test)" and GB / T 3903.6-2017 "Test Methods for Shoes - Antislip Performance". The hardness was 63A, the layer thickness was 80μm, the SATRA dry antislip score was 0.84, the wet antislip score was 0.48, and the DIN value at room temperature (25℃) was 21mm. 3 High temperature (80℃) DIN is 42mm 3 Yellowing resistance level is 3-4.

[0047] Example 3 A micro-crosslinked polyurea polyurethane shoe sole, wherein the first component comprises the following components in the following molar ratio: 10 parts isophorone diisocyanate, 6 parts poly(ε-caprolactone diol) (molecular weight ~2000), 2 parts pentanediol, and 2 parts isophorone diamine; the second component is trimer IPDI, and the mass percentage of the second component is 2.5% of the mass of the first component; the organic solvent is DMAc; and the solid content is 20%.

[0048] The outsole processing was completed using the above-described method for applying micro-crosslinked polyurea polyurethane to athletic shoe outsoles, with the coating method being brush coating.

[0049] The prepared shoe outsole was tested according to GB / T 9867 "Determination of Abrasion Resistance of Vulcanized Rubber or Thermoplastic Rubber (Rotary Roller Abrasion Test)" and GB / T 3903.6-2017 "Test Methods for Shoe Shoes - Antislip Performance". The hardness was 68A, the layer thickness was 120μm, the SATRA dry antislip score was 0.79, the wet antislip score was 0.56, and the DIN value at room temperature (25℃) was 19mm. 3 High temperature (80℃) DIN is 38mm 3 Yellowing resistance level is 3-4.

[0050] Example 4 A micro-crosslinked polyurea polyurethane shoe sole, wherein the first component comprises the following components in molar proportions: 10 parts hexamethylene diisocyanate (HDI), 4 parts polyethylene adipate diol (molecular weight ~2000), 1.5 parts butanediol, and 4.5 parts diethyltoluene diamine; the second component is triphenylmethane triisocyanate, and the mass percentage of the second component is 3.5% of the mass of the first component; the organic solvent is DMAc; and the solid content is 25%.

[0051] The outsole processing was completed using the above-described method for applying micro-crosslinked polyurea polyurethane to athletic shoe outsoles, with the coating method being brush coating.

[0052] The prepared shoe outsole was tested according to GB / T 9867 "Determination of Abrasion Resistance of Vulcanized Rubber or Thermoplastic Rubber (Rotary Roller Abrasion Test)" and GB / T 3903.6-2017 "Test Methods for Shoe Shoes - Antislip Performance". The hardness was 70A, the layer thickness was 200μm, the SATRA dry antislip score was 0.92, the wet antislip score was 0.49, and the DIN value at room temperature (25℃) was 15mm. 3 High temperature (80℃) DIN is 32mm 3 Yellowing resistance level is 3-4.

[0053] Comparative Example 1 A polyurea polyurethane shoe sole contains only a first component, the components of which are in the following molar ratios: 10 parts methylene diphenyl diisocyanate (MDI), 8 parts polytetrahydrofuran ether diol (molecular weight ~2000), 1.5 parts butanediol, and 0.5 parts hexamethylenediamine; the organic solvent is DMF; and the solid content is 10%.

[0054] Referring to the above-mentioned processing method for applying micro-crosslinked polyurea polyurethane to the outsole of sports shoes (without adding a second component), the outsole processing was completed, and the coating method was spraying.

[0055] The prepared shoe outsole was tested according to GB / T 9867 "Determination of Abrasion Resistance of Vulcanized Rubber or Thermoplastic Rubber (Rotary Roller Abrasion Test)" and GB / T 3903.6-2017 "Test Methods for Shoe Shoes - Antislip Performance". The hardness was 55A, the layer thickness was 100μm, the SATRA dry antislip score was 0.92, the wet antislip score was 0.49, and the DIN value at room temperature (25℃) was 48mm. 3 High temperature (80℃) DIN is 65mm 3 Yellowing resistance level is 3-4.

[0056] Comparative Example 2 A deeply cross-linked polyurea polyurethane shoe sole, wherein the first component comprises the following components in the following molar ratio: 10 parts of methylene diphenyl diisocyanate (MDI), 8 parts of polytetrahydrofuran ether glycol (molecular weight ~2000), 1.5 parts of butanediol, and 0.5 parts of hexamethylenediamine; the second component is trimeric diisocyanate (HDI), and the mass percentage of the second component is 8% of the mass of the first component; the organic solvent is DMF; and the solid content is 10%.

[0057] Referring to the above-mentioned processing method for applying micro-crosslinked polyurea polyurethane to sports shoe outsoles, the shoe outsole processing was completed, and the coating method was spraying.

[0058] The prepared shoe outsole was tested according to GB / T 9867 "Determination of Abrasion Resistance of Vulcanized Rubber or Thermoplastic Rubber (Rotary Roller Abrasion Test)" and GB / T 3903.6-2017 "Test Methods for Shoes - Antislip Performance". The hardness was 78A, the layer thickness was 100μm, the SATRA dry antislip was 0.66, the wet antislip was 0.34, and the DIN value at room temperature (25℃) was 40mm. 3 High temperature (80℃) DIN is 56mm 3 Yellowing resistance level is 3-4.

[0059] As shown in Examples 1-4, the shoe outsoles made using the micro-crosslinked polyurea polyurethane of the present invention have a hardness of 58-70A, a film thickness of 50-200μm, a SATRA dry slip resistance of 0.79-0.92, a wet slip resistance of 0.45-0.56, and a DIN thickness of 15-25mm at room temperature (25℃). 3 High temperature DIN is 32~45mm 3 It has a yellowing resistance rating of 3-4, and generally exhibits good anti-slip and wear resistance, as well as good heat wear resistance.

[0060] As shown in Comparative Example 1, the shoe outsole prepared by coating with conventional polyurea polyurethane material contains only long-chain polyurea polyurethane structures without additional cross-linking points. This results in excellent softness and high damping, leading to good anti-slip performance in the resulting outsole, but its abrasion resistance is significantly inferior to the micro-crosslinked polyurea polyurethane of this invention. In Comparative Example 2, the content of the second component in the deeply crosslinked polyurea polyurethane material exceeds the limits defined in this invention, resulting in a higher number of intramolecular cross-linking points. Although the material's hardness increases, it tends to become brittle, leading to a decrease in toughness, as well as a reduction in both anti-slip and abrasion resistance.

[0061] The present invention has been further described above with reference to specific embodiments, which are merely preferred embodiments and should not be construed as limiting the substance and scope of the invention. Any simple modifications or equivalent variations made by those skilled in the art to the above embodiments after reading this specification fall within the protection scope of the present invention. The various specific technical features described in the above embodiments can be combined in any suitable manner without contradiction. To avoid unnecessary repetition, the embodiments of the present invention will not further describe various possible combinations.

Claims

1. A micro-crosslinked polyurea polyurethane, characterized in that, It includes a first component and a second component. The first component is a polyurea polyurethane base material prepared by polymerization reaction of diisocyanate, prepolymer diol, diol chain extender and diamine chain extender. The second component is a polyisocyanate compound, including at least one of HDI trimer, TDI trimer, IPDI trimer and triphenylmethane triisocyanate. The first and second components are mixed evenly in an organic solvent to form a mixed solution, and a micro-crosslinking / self-curing reaction spontaneously occurs in the solution to form micro-crosslinked polyurea polyurethane; the mass ratio of the second component is 0.5~5% of the mass of the first component.

2. The micro-crosslinked polyurea polyurethane as described in claim 1, characterized in that, The organic solvent is at least one of N,N-dimethylformamide, N,N-dimethylacetamide, tetrahydrofuran, pyridine, and carbon tetrachloride.

3. The micro-crosslinked polyurea polyurethane as described in claim 1, characterized in that, The solid content of the mixed solution is controlled within 5-30% to facilitate coating on the carrier and curing to form micro-crosslinked polyurea polyurethane.

4. The micro-crosslinked polyurea polyurethane as described in claim 1, characterized in that, The diisocyanate may be an aromatic diisocyanate or an aliphatic diisocyanate. The aromatic diisocyanate includes at least one of methylene diphenyl diisocyanate, toluene diisocyanate, terephthalic diisocyanate, and diphenylmethylene diisocyanate. The aliphatic diisocyanate includes at least one of hexamethylene diisocyanate, methylene dicyclohexyl diisocyanate, isophorone diisocyanate, and cyclohexane dimethylene diisocyanate.

5. The micro-crosslinked polyurea polyurethane as described in claim 1, characterized in that, The diol prepolymer is at least one of polyethylene adipate, propylene adipate, butylene adipate, poly(ε-caprolactone diol), polycarbonate diol, polyethylene oxide homopolymer diol, polypropylene oxide homopolymer diol, and polytetrahydrofuran ether diol.

6. The microcrosslinked polyurea polyurethane as described in claim 1, characterized in that, The diol chain extender is at least one selected from ethylene glycol, 1,3-propanediol, 1,4-butanediol, 1,5-pentanediol, and 1,6-hexanediol.

7. The micro-crosslinked polyurea polyurethane as described in claim 1, characterized in that, Furthermore, the diamine chain extender is at least one selected from ethylenediamine, butanediamine, hexamethylenediamine, isophoronediamine, 3,5-dimethylthiotoluenediamine, diethyltoluenediamine, 1,3-propanediol bis(4-aminobenzoate), 4,4'-methylenebis(2-ethyl)aniline, and bis-sec-butylaminodiphenylmethane.

8. The microcrosslinked polyurea polyurethane according to any one of claims 1 to 7, characterized in that, Furthermore, the molar ratio of diisocyanate, diol prepolymer, and diol / amine chain extender is 10:2~8:8~2, that is, the molar amount of diisocyanate is the sum of the molar amounts of diol prepolymer and diol / amine chain extender, wherein the molar ratio of diol prepolymer and diol / amine chain extender is between 1:4 and 4:1; and the molar ratio of diol chain extender to diamine chain extender is between 3:1 and 1:

3.

9. A method for applying micro-crosslinked polyurea polyurethane, characterized in that, The micro-crosslinked polyurea polyurethane of claim 8 comprises the following steps: S1. Weigh out diisocyanate, prepolymer diol, diol chain extender and diamine chain extender according to the proportion, and prepare the first component by polymerization reaction. After drying, store for later use. S2. Treat the shoe midsole surface with cleaning agent and surfactant in sequence, and ensure that the next step is carried out within 12 hours; S3. Dissolve the first component in an organic solvent. After it is completely dissolved, add the second component and mix it evenly. Apply it to the shoe midsole that has undergone surface treatment in step S2 within 2 hours. S4. Place the coated shoe midsole in an oven and wait for the surface coating to cure before transferring it to a ventilated area until the solvent has completely evaporated, thus completing the shoe outsole production.

10. A footwear product, characterized in that, The shoe outsole is made using the above-mentioned method for applying micro-crosslinked polyurea polyurethane.