A high-resilience and aging-resistant TPU sports shoe sole and its preparation method

Abstract

The present invention relates to the field of shoe sole production technology, and in particular to a high-resilience, aging-resistant TPU sports shoe sole and a method for preparing the same. The TPU sports shoe sole comprises a TPU composite film and a TPU midsole disposed on the surface of the TPU composite film. The TPU composite film is a double-layer co-extruded film made by a cast co-extrusion process of TPU particles and TPU hot-melt adhesive particles. By integrally forming the TPU composite film and the TPU midsole, the present invention significantly reduces the weight of the sole, effectively simplifies the production process, and imparts excellent resilience, wear resistance, and anti-slip properties to the TPU sports shoe sole, making the sole more evenly stressed in all directions. This improves the comfort of the TPU sports shoe sole and provides stable foot protection.

Description

Technical Field

[0001] The invention relates to the technical field of sole production, and in particular to a high-rebound and aging-resistant TPU sports shoe sole and a preparation method thereof. Background Art

[0002] With improved living standards, people are placing higher demands on the comfort and functionality of their shoes. Foam soles, with their remarkable combination of lightness, comfort, and high elasticity, are being used in the soles of various sports shoes. Common foam materials used in the industry include EVA, SBS, PVC, and TPU. However, these materials all have drawbacks, such as EVA's low slip resistance and significant hardening at low temperatures; SBS's poor heat and wear resistance; and PVC's poor wear and cold resistance. TPU, on the other hand, faces challenges such as high cost, yellowing, and a lack of anti-slip properties. However, compared to other foam materials, TPU offers significant advantages in comfort, resilience, and wear resistance. Using TPU for shoe manufacturing offers simple processing and superior performance. Therefore, in-depth research on TPU sports shoe sole materials is urgently needed to provide more and better options for the high-quality sole manufacturing industry. Summary of the Invention

[0003] The purpose of the present invention is to provide a high-resilience and aging-resistant TPU sports shoe sole and a preparation method thereof in order to solve the above-mentioned deficiencies in the prior art.

[0004] The purpose of the present invention is achieved through the following technical solution: The present invention provides a high-resilience and aging-resistant TPU sports shoe sole, including a TPU composite film and a TPU midsole arranged on the surface of the TPU composite film. The TPU composite film is a double-layer co-extruded film made of TPU particles and TPU hot-melt adhesive particles through a cast co-extrusion process.

[0005] Furthermore, the TPU particles include the following raw materials in parts by weight: 60-80 parts of TPU elastomer, 3-8 parts of plasticizer, 0.5-6 parts of anti-yellowing agent, 0.1-1.5 parts of lubricant and 0-10 parts of colorant.

[0006] Furthermore, the preparation method of the TPU elastomer includes the following steps: heating and melting polycaprolactone diol and vacuum dehydrating it, then transferring it to a reactor, raising the temperature to 90-100°C, adding 4,4-dicyclohexyltoluene diisocyanate in batches under a nitrogen atmosphere, adding a small amount of organic tin catalyst to carry out a prepolymerization reaction after the temperature stabilizes, and then adding a chain extender and carbodiimide to carry out a chain extension reaction after completion, and then transferring it to a mold for curing and demolding to obtain the TPU elastomer.

[0007] Furthermore, the R value of the prepolymerization reaction system is 2.0, the chain extender is at least one of 1,4-hexanediol, TDMA-G55, and 3,3'-dichloro-4,4'-diphenylmethanediamine, the amount of the chain extender is 8-10% of the total amount of polycaprolactone diol and 4,4-dicyclohexyltoluene diisocyanate, and the amount of the carbodiimide is 0.05-0.2% of the total amount of polycaprolactone diol and 4,4-dicyclohexyltoluene diisocyanate.

[0008] Furthermore, the plasticizer is at least one of dioctyl oxalate, dioctyl sebacate, epoxy fatty acid methyl ester, and propylene glycol adipate polyester.

[0009] Furthermore, the lubricant is at least one of amino silicone oil, zinc stearate, and stearamide.

[0010] Furthermore, the anti-yellowing agent is at least one of a hindered amine light stabilizer, a UV absorber, and an antioxidant. The hindered amine light stabilizer is preferably Light Stabilizer 783, the UV absorber is preferably GSSORB UV-571 or UV-1130, and the antioxidant is at least one of GSINOX DHOP, GSINOX 5057, and GSINOX 1135.

[0011] Furthermore, the colorant can be an organic pigment, such as phthalocyanine blue, or an inorganic pigment such as titanium dioxide, carbon black, etc. The choice of colorant is determined by the application scenario requirements, giving the TPU particles an optional color.

[0012] Furthermore, the TPU particles also include foamed particles. The preparation method of the foamed particles is specifically as follows: 5-8 parts of polyborosiloxane and 0.3-1 parts of a compatibilizer are evenly mixed and added to an internal mixer; 50-60 parts of ethylene-vinyl acetate copolymer, 30-40 parts of a polyolefin elastomer, 0.1-0.5 parts of a coupling agent and 0.5-3 parts of a filler are added thereto, first heated to 80°C for preheating and stirring, then heated to 120-125°C, 0.5-1 parts of a cross-linking agent and 2-4 parts of a foaming agent are added and continued to stir to obtain an internal mixing rubber compound; transferred to an open mixer at 80-90°C for mixing, and the mixed rubber compound is granulated by an extruder; the granulated rubber particles are placed in a foaming device, and the rubber particles are foamed by heating to obtain the foamed particles.

[0013] The compatibilizer is maleic anhydride grafted polyethylene or maleic anhydride grafted polypropylene, the coupling agent is hydroxy-terminated polydimethylsiloxane, the filler is one or more of white carbon black, calcium carbonate, and zinc stearate, the crosslinking agent is di-tert-butyl peroxide, and the foaming agent is azodicarbonamide.

[0014] Furthermore, the preparation method of the TPU hot melt rubber particles includes the following steps: S1, placing polyester polyol, inorganic filler, tackifying resin, and thermoplastic resin in a reaction container, heating and stirring to 120-140° C., controlling the vacuum pressure at 50-100 Pa, and maintaining for 1-1.5 hours;

[0015] S2, heating the aromatic polyisocyanate to a molten state, and then placing it in the reaction vessel of step S1 to react at a temperature of 80-120° C., and stopping the reaction when the -NCO group content in the reaction system reaches the theoretical calculated value;

[0016] S3, add silane coupling agent and stir for 10-20 minutes, then add dimorpholinyl diethyl ether and thermoplastic resin and continue stirring for 10-20 minutes to mix well;

[0017] S4. Control the pressure of the reaction container to be less than 100 Pa, perform degassing treatment, and granulate the obtained product through an extruder or a granulator to obtain the TPU hot melt rubber particles.

[0018] Furthermore, the polyester polyol is compounded by an amorphous polyester polyol and a crystalline polyester polyol in a mass ratio of 1:1-1.5, wherein the amorphous polyester polyol is polybutylene adipate diol or polyethylene adipate diol, and the crystalline polyester polyol is preferably crystalline polybutylene adipate or polyethylene terephthalate polyol.

[0019] Furthermore, the aromatic polyisocyanate is preferably 4,4'-diphenylmethane diisocyanate, diphenylmethane 2,4"-diisocyanate or toluene diisocyanate. In the above reaction system, the isocyanate index is preferably 1.8.

[0020] Furthermore, the inorganic filler is at least one of fumed silica, talc, and kaolin, and the amount of the inorganic filler is 0.3-0.6 wt% of the total amount of the polyester polyol and the aromatic polyisocyanate. The tackifying resin is at least one of terpene phenol resin, tert-butylphenol resin, or natural rosin resin, and the amount of the tackifying resin is 12-18% of the total amount of the polyester polyol and the aromatic polyisocyanate. The thermoplastic resin is a semi-crystalline linear polycaprolactone-based thermoplastic polyurethane resin, and the amount of the thermoplastic resin is 18-20 wt% of the total amount of the polyester polyol and the aromatic polyisocyanate. The silane coupling agent is KH550 or KH560, and the amount of the silane coupling agent is 0.1-1% of the total amount of the polyester polyol and the aromatic polyisocyanate.

[0021] The present invention also provides a method for preparing the above-mentioned sports shoe sole sheet, comprising the following preparation steps:

[0022] (1) Take the TPU composite film and press it into the desired shape through a mold to obtain a TPU outsole;

[0023] (2) placing the TPU outsole obtained in step (1) into the reserved TPU outsole position in the secondary hot pressing mold, and then placing the TPU midsole;

[0024] (3) The TPU outsole and the TPU midsole are formed into one piece by first performing a hot pressing treatment on the secondary hot pressing mold and then performing a cold pressing treatment, thereby obtaining the TPU sports shoe bottom sheet.

[0025] Furthermore, in step (3), the temperature of the hot pressing treatment is 150-160° C., and the time is 300-500 s; the temperature of the cold pressing treatment is 35-37° C., and the time is 400-600 s.

[0026] The beneficial effects of the present invention are:

[0027] (1) The present invention can significantly reduce the weight of the sole by integrally forming the TPU composite film and the TPU midsole, while effectively simplifying the production process, and giving the TPU sports shoe sole good resilience, wear resistance and anti-slip properties, so that the sole is subjected to more uniform force in all directions, thereby improving the comfort of the TPU sports shoe sole and the stable protection of the foot;

[0028] (2) The present invention adopts a cast co-extrusion process to form TPU particles and TPU hot-melt adhesive particles into a double-layer composite film, so that the formed side of the TPU hot-melt adhesive particles can be better bonded and pressed with the TPU midsole. The TPU hot-melt adhesive particles prepared by the above method have high adhesive strength, good weather resistance and temperature resistance, thereby improving the structural strength of the TPU sports shoe bottom sheet and preventing delamination;

[0029] (3) The TPU particles prepared by the present invention using raw materials such as TPU elastomer, plasticizer, anti-yellowing agent and lubricant have the characteristics of high strength and high elasticity, yellowing and aging resistance, hydrolysis resistance and easy processing, thereby giving the TPU sports shoe bottom sheet good advantages such as good yellowing and aging resistance, hydrolysis resistance and high tensile strength;

[0030] (4) The present invention further improves the resilience and shock absorption of the TPU composite film by adding foamed particles in the preparation of TPU particles, thereby significantly improving the comfort and rebound of the TPU sports shoe sole, and also improving the anti-slip property of the TPU sports shoe sole. DETAILED DESCRIPTION

[0031] In order to facilitate understanding by those skilled in the art, the present invention will be further described below with reference to the embodiments. The contents mentioned in the embodiments are not intended to limit the present invention.

[0032] Example 1

[0033] This embodiment provides a high-resilience and aging-resistant TPU sports shoe sole, including a TPU composite film and a TPU midsole arranged on the surface of the TPU composite film. The TPU composite film is a double-layer co-extruded film made of TPU particles and TPU hot-melt adhesive particles through a cast co-extrusion process.

[0034] Furthermore, the TPU particles include the following raw materials in parts by weight: 62 parts of TPU elastomer, 3 parts of plasticizer, 0.8 parts of anti-yellowing agent, and 0.4 parts of lubricant.

[0035] Furthermore, the preparation method of the TPU elastomer includes the following steps: the preparation method of the TPU elastomer includes the following steps: heating and melting polycaprolactone diol at 110°C and a vacuum degree of 90Pa and vacuum dehydrating for 2 hours, then transferring it to a reactor, raising the temperature to 90°C, adding 4,4-dicyclohexyltoluene diisocyanate in batches under a nitrogen atmosphere and stirring rapidly, adding 1 drop of stannous octoate to carry out a prepolymerization reaction after the temperature stabilizes, and the reaction is completed after the isocyanate group content reaches the theoretical value, and then vacuum degassing the obtained polyurethane prepolymer for 10 minutes. After completion, a chain extender and carbodiimide are added to carry out a chain extension reaction, and then transferred to a preheated mold for curing and demolding to obtain the TPU elastomer.

[0036] Furthermore, the R value of the prepolymerization reaction system is 2.0, the chain extender is 3,3'-dichloro-4,4'-diphenylmethanediamine, the amount of the chain extender is 8% of the total amount of polycaprolactone diol and 4,4-dicyclohexyltoluene diisocyanate, and the amount of the carbodiimide is 0.08% of the total amount of polycaprolactone diol and 4,4-dicyclohexyltoluene diisocyanate.

[0037] Furthermore, the plasticizer is dioctyl oxalate.

[0038] Furthermore, the lubricant is zinc stearate.

[0039] Furthermore, the anti-yellowing agent is compounded with a hindered amine light stabilizer, a UV absorber, and an antioxidant in a mass ratio of 2:1:1, wherein the hindered amine light stabilizer is light stabilizer 783, the UV absorber is GSSORB UV-571, and the antioxidant is GSINOX 1135.

[0040] Furthermore, the preparation method of the TPU hot melt rubber particles includes the following steps: S1, placing polyester polyol, inorganic filler, tackifying resin, and thermoplastic resin in a reaction container, heating and stirring to 125° C., controlling the vacuum pressure at 90 Pa, and maintaining for 1.5 hours;

[0041] S2, heating the aromatic polyisocyanate to a molten state, and then placing it in the reaction vessel of step S1 to react at a reaction temperature of 90° C., and stopping the reaction when the -NCO group content in the reaction system reaches the theoretical calculated value;

[0042] S3, adding silane coupling agent and stirring for 15 minutes, then adding dimorpholinyl diethyl ether and thermoplastic resin and continuing to stir for 15 minutes, and mixing evenly;

[0043] S4. Control the pressure of the reaction container to be less than 100 Pa, perform degassing treatment, and granulate the obtained product through an extruder or a granulator to obtain the TPU hot melt rubber particles.

[0044] Furthermore, the polyester polyol is compounded by amorphous polyester polyol and crystalline polyester polyol in a mass ratio of 1:1.2, wherein the amorphous polyester polyol is polybutylene adipate diol and the crystalline polyester polyol is crystalline polybutylene adipate diol.

[0045] Furthermore, the aromatic polyisocyanate is diphenylmethane 2,4'-diisocyanate. In the above reaction system, the isocyanate index is preferably 1.8.

[0046] Furthermore, the inorganic filler is a compound of fumed silica and kaolin in a mass ratio of 1.3:1, and the amount of the inorganic filler is 0.3wt% of the total amount of the polyester polyol and aromatic polyisocyanate. The tackifying resin is a terpene phenol resin, and the amount of the tackifying resin is 13% of the total amount of the polyester polyol and aromatic polyisocyanate. The thermoplastic resin is a semi-crystalline linear polycaprolactone-based thermoplastic polyurethane resin, and the amount of the thermoplastic resin is 18wt% of the total amount of the polyester polyol and aromatic polyisocyanate. The silane coupling agent is KH550, and the amount of the silane coupling agent is 0.2% of the total amount of the polyester polyol and aromatic polyisocyanate.

[0047] The present invention also provides a method for preparing the above-mentioned sports shoe sole sheet, comprising the following preparation steps:

[0048] (1) Take the TPU composite film and press it into the desired shape through a mold to obtain a TPU outsole;

[0049] (2) placing the TPU outsole obtained in step (1) into the reserved TPU outsole position in the secondary hot pressing mold, and then placing the TPU midsole;

[0050] (3) The TPU outsole and the TPU midsole are formed into one piece by first performing a hot pressing treatment on the secondary hot pressing mold and then performing a cold pressing treatment, thereby obtaining the TPU sports shoe bottom sheet.

[0051] Furthermore, in step (3), the temperature of the hot pressing treatment is 150° C. and the time is 400 s; the temperature of the cold pressing treatment is 36° C. and the time is 500 s.

[0052] Example 2

[0053] This embodiment provides a high-resilience and aging-resistant TPU sports shoe sole, including a TPU composite film and a TPU midsole arranged on the surface of the TPU composite film. The TPU composite film is a double-layer co-extruded film made of TPU particles and TPU hot-melt adhesive particles through a cast co-extrusion process.

[0054] Furthermore, the TPU particles include the following raw materials in parts by weight: 70 parts of TPU elastomer, 5 parts of plasticizer, 3 parts of anti-yellowing agent, and 0.7 parts of lubricant.

[0055] Furthermore, the preparation method of the TPU elastomer includes the following steps: the preparation method of the TPU elastomer includes the following steps: heating and melting polycaprolactone diol at 110°C and a vacuum degree of 90Pa and vacuum dehydrating for 2 hours, then transferring it to a reactor, raising the temperature to 95°C, adding 4,4-dicyclohexyltoluene diisocyanate in batches under a nitrogen atmosphere and stirring rapidly, adding 1 drop of stannous octoate to carry out a prepolymerization reaction after the temperature stabilizes, and the reaction is completed after the isocyanate group content reaches the theoretical value, and then the obtained polyurethane prepolymer is vacuum degassed for 10 minutes. After completion, a chain extender and carbodiimide are added to carry out a chain extension reaction, and then transferred to a preheated mold for curing and demolding to obtain the TPU elastomer.

[0056] Furthermore, the R value of the prepolymerization reaction system is 2.0, the chain extender is TDMA-G55, the amount of the chain extender is 9% of the total amount of polycaprolactone diol and 4,4-dicyclohexyltoluene diisocyanate, and the amount of the carbodiimide is 0.1% of the total amount of polycaprolactone diol and 4,4-dicyclohexyltoluene diisocyanate.

[0057] Furthermore, the plasticizer is propylene glycol adipate polyester.

[0058] Furthermore, the lubricant is amino silicone oil.

[0059] Furthermore, the anti-yellowing agent is compounded from a hindered amine light stabilizer, a UV absorber, and an antioxidant in a mass ratio of 2:1:1, wherein the hindered amine light stabilizer is light stabilizer 783, the UV absorber is GSSORB UV-571, and the antioxidant is GSINOX DHOP.

[0060] Furthermore, the TPU particles also include foamed particles. The preparation method of the foamed particles is specifically as follows: 6 parts of polyborosiloxane and 0.6 parts of a compatibilizer are mixed evenly and added to an internal mixer; then 55 parts of ethylene-vinyl acetate copolymer, 32 parts of a polyolefin elastomer, 0.3 parts of a coupling agent and 1.2 parts of a filler are added thereto, first heated to 80°C for preheating and stirring, then heated to 120°C, 0.5 parts of a cross-linking agent and 3 parts of a foaming agent are added and continued to stir to obtain an internal mixing rubber compound; transferred to an open mixer at 85°C for mixing, and the mixed rubber compound is granulated by an extruder; the granulated rubber particles are placed in a foaming device, and the rubber particles are foamed by heating to obtain the foamed particles.

[0061] Wherein, the compatibilizer is maleic anhydride grafted polypropylene, the coupling agent is hydroxyl-terminated polydimethylsiloxane, the filler is zinc stearate, the cross-linking agent is di-tert-butyl peroxide, and the foaming agent is azodicarbonamide.

[0062] Furthermore, the preparation method of the TPU hot melt rubber particles includes the following steps: S1, placing polyester polyol, inorganic filler, tackifying resin, and thermoplastic resin in a reaction container, heating and stirring to 130° C., controlling the vacuum pressure at 90 Pa, and maintaining for 1.5 hours;

[0063] S2, heating the aromatic polyisocyanate to a molten state, and then placing it in the reaction vessel of step S1 to react at a reaction temperature of 95° C., and stopping the reaction when the -NCO group content in the reaction system reaches the theoretical calculated value;

[0064] S3, adding silane coupling agent and stirring for 15 minutes, then adding dimorpholinyl diethyl ether and thermoplastic resin and continuing to stir for 15 minutes, and mixing evenly;

[0065] S4. Control the pressure of the reaction container to be less than 100 Pa, perform degassing treatment, and granulate the obtained product through an extruder or a granulator to obtain the TPU hot melt rubber particles.

[0066] Furthermore, the polyester polyol is compounded by an amorphous polyester polyol and a crystalline polyester polyol in a mass ratio of 1:1-1.5, wherein the amorphous polyester polyol is polybutylene adipate diol and the crystalline polyester polyol is crystalline polybutylene adipate or polyethylene terephthalate polyol.

[0067] Furthermore, the aromatic polyisocyanate is preferably 4,4'-diphenylmethane diisocyanate. In the above reaction system, the isocyanate index is 1.8.

[0068] Furthermore, the inorganic filler is a compound of fumed silica and kaolin in a mass ratio of 1.3:1, and the amount of the inorganic filler is 0.4wt% of the total amount of the polyester polyol and aromatic polyisocyanate. The tackifying resin is a tert-butylphenol-formaldehyde resin, and the amount of the tackifying resin is 14% of the total amount of the polyester polyol and aromatic polyisocyanate. The thermoplastic resin is a semi-crystalline linear polycaprolactone-based thermoplastic polyurethane resin, and the amount of the thermoplastic resin is 19wt% of the total amount of the polyester polyol and aromatic polyisocyanate. The silane coupling agent is KH550, and the amount of the silane coupling agent is 0.4% of the total amount of the polyester polyol and aromatic polyisocyanate.

[0069] Example 3

[0070] This embodiment provides a high-resilience and aging-resistant TPU sports shoe sole, including a TPU composite film and a TPU midsole arranged on the surface of the TPU composite film. The TPU composite film is a double-layer co-extruded film made of TPU particles and TPU hot-melt adhesive particles through a cast co-extrusion process.

[0071] Furthermore, the TPU particles include the following raw materials in parts by weight: 75 parts of TPU elastomer, 6 parts of plasticizer, 5 parts of anti-yellowing agent, 1.3 parts of lubricant and 3 parts of colorant.

[0072] Furthermore, the preparation method of the TPU elastomer includes the following steps: the preparation method of the TPU elastomer includes the following steps: heating and melting polycaprolactone diol at 110°C and a vacuum degree of 90Pa and vacuum dehydrating for 2 hours, then transferring it to a reactor, raising the temperature to 95°C, adding 4,4-dicyclohexyltoluene diisocyanate in batches under a nitrogen atmosphere and stirring rapidly, adding 1 drop of stannous octoate to carry out a prepolymerization reaction after the temperature stabilizes, and the reaction is completed after the isocyanate group content reaches the theoretical value, and then the obtained polyurethane prepolymer is vacuum degassed for 10 minutes. After completion, a chain extender and carbodiimide are added to carry out a chain extension reaction, and then transferred to a preheated mold for curing and demolding to obtain the TPU elastomer.

[0073] Furthermore, the R value of the prepolymerization reaction system is 2.0, the chain extender is 3,3'-dichloro-4,4'-diphenylmethanediamine, the amount of the chain extender is 10% of the total amount of polycaprolactone diol and 4,4-dicyclohexyltoluene diisocyanate, and the amount of the carbodiimide is 0.15% of the total amount of polycaprolactone diol and 4,4-dicyclohexyltoluene diisocyanate.

[0074] Furthermore, the plasticizer is epoxy fatty acid methyl ester.

[0075] Furthermore, the lubricant is stearamide.

[0076] Furthermore, the anti-yellowing agent is compounded with a hindered amine light stabilizer, an ultraviolet absorber, and an antioxidant in a mass ratio of 2:1:1, wherein the hindered amine light stabilizer is light stabilizer 783, the ultraviolet absorber is UV-1130, and the antioxidant is GSINOX 5057.

[0077] Furthermore, the TPU particles also include foamed particles. The preparation method of the foamed particles is specifically as follows: 7 parts of polyborosiloxane and 0.8 parts of a compatibilizer are evenly mixed and added to an internal mixer; then 60 parts of ethylene-vinyl acetate copolymer, 38 parts of a polyolefin elastomer, 0.4 parts of a coupling agent and 2 parts of a filler are added thereto, first heated to 80°C for preheating and stirring, then heated to 125°C, 1 part of a cross-linking agent and 3 parts of a foaming agent are added and continued to stir to obtain an internal mixing rubber compound; transferred to an open mixer at 85°C for mixing, and the mixed rubber compound is granulated by an extruder; the granulated rubber particles are placed in a foaming device, and the rubber particles are foamed by heating to obtain the foamed particles.

[0078] Wherein, the compatibilizer is maleic anhydride grafted polyethylene, the coupling agent is hydroxyl-terminated polydimethylsiloxane, the filler is calcium carbonate, the cross-linking agent is di-tert-butyl peroxide, and the foaming agent is azodicarbonamide.

[0079] Furthermore, the preparation method of the TPU hot melt rubber particles includes the following steps: S1, placing polyester polyol, inorganic filler, tackifying resin, and thermoplastic resin in a reaction container, heating and stirring to 135° C., controlling the vacuum pressure at 100 Pa, and maintaining for 1.5 hours;

[0080] S2, heating the aromatic polyisocyanate to a molten state, and then placing it in the reaction vessel of step S1 to react at a reaction temperature of 105° C., and stopping the reaction when the -NCO group content in the reaction system reaches the theoretical calculated value;

[0081] S3, adding silane coupling agent and stirring for 15 minutes, then adding dimorpholinyl diethyl ether and thermoplastic resin and continuing to stir for 15 minutes, and mixing evenly;

[0082] S4. Control the pressure of the reaction container to be less than 100 Pa, perform degassing treatment, and granulate the obtained product through an extruder or a granulator to obtain the TPU hot melt rubber particles.

[0083] Furthermore, the polyester polyol is compounded by an amorphous polyester polyol and a crystalline polyester polyol in a mass ratio of 1:1-1.5, wherein the amorphous polyester polyol is polybutylene adipate diol, and the crystalline polyester polyol is crystalline polybutylene adipate or polyethylene terephthalate polyol.

[0084] Furthermore, the aromatic polyisocyanate is toluene diisocyanate. In the above reaction system, the isocyanate index is 1.8.

[0085] Furthermore, the inorganic filler is a compound of fumed silica and kaolin in a mass ratio of 1.3:1, and the amount of the inorganic filler is 0.3-0.6wt% of the total amount of the polyester polyol and aromatic polyisocyanate. The tackifying resin is a natural rosin resin, and the amount of the tackifying resin is 16% of the total amount of the polyester polyol and aromatic polyisocyanate. The thermoplastic resin is a semi-crystalline linear polycaprolactone-based thermoplastic polyurethane resin, and the amount of the thermoplastic resin is 18wt% of the total amount of the polyester polyol and aromatic polyisocyanate. The silane coupling agent is KH560, and the amount of the silane coupling agent is 0.7% of the total amount of the polyester polyol and aromatic polyisocyanate.

[0086] The present invention also provides a method for preparing the above-mentioned sports shoe sole sheet, comprising the following preparation steps:

[0087] (1) Take the TPU composite film and press it into the desired shape through a mold to obtain a TPU outsole;

[0088] (2) placing the TPU outsole obtained in step (1) into the reserved TPU outsole position in the secondary hot pressing mold, and then placing the TPU midsole;

[0089] (3) The TPU outsole and the TPU midsole are formed into one piece by first performing a hot pressing treatment on the secondary hot pressing mold and then performing a cold pressing treatment, thereby obtaining the TPU sports shoe bottom sheet.

[0090] Furthermore, in step (3), the temperature of the hot pressing treatment is 155° C. and the time is 400 s; the temperature of the cold pressing treatment is 36° C. and the time is 500 s.

[0091] Comparative Example 1

[0092] The difference between this comparative example and Example 2 is that a commercially available TPU elastomer (Taiwan Risheng 1730-60) is used to replace the TPU elastomer in Example 2.

[0093] Comparative Example 2

[0094] The difference between this comparative example and Example 2 is that this comparative example uses antioxidant 1010 to replace the anti-yellowing agent in Example 2.

[0095] Comparative Example 3

[0096] The difference between this comparative example and Example 3 is that commercially available EVA foam particles (Beijing Yanshan EVA 18J3) are used to replace the foam particles in Example 3.

[0097] The TPU sports shoe soles prepared in Examples 1-3 and Comparative Examples 1-3 were tested for tensile strength, resilience, aging resistance, bending resistance, and anti-slip strength. The tensile strength was measured using the GB / T1040.3-2006 standard.

[0098] The rebound rate was measured using ASTM D2632-2001; the aging resistance was measured using QUV 340nm for 1000 hours at an illumination intensity of 800W / cm2; the bending resistance was measured using GB / T 3903.1-2017 (bending angle 50°, bending frequency 230 times / min); and the anti-slip force was measured using GB / T 28287-2012. The test results are shown in the table below:

[0099]

[0100] The above results show that the TPU sports shoe soles prepared in Examples 1-3 of the present invention exhibit balanced and excellent mechanical strength, aging resistance, and bending resistance. Specifically, the tensile strength is above 40 MPa, the rebound force is greater than 46%, and the bending resistance is greater than 120,000 times. Furthermore, the tensile strength of the soles changes slightly after 1000 hours of UV aging, indicating good aging resistance and UV stability. On the other hand, the TPU sports shoe sole prepared in Example 1 is slightly inferior to that of Examples 2 and 3 in terms of anti-slip properties. This is mainly because the introduction of the expanded particles plays an important role in improving the dry and wet anti-slip properties of the TPU sports shoe sole.

[0101] The above specific embodiments are further explanations of the technical solutions and beneficial effects of the present invention, and are not intended to limit the implementation methods. For those skilled in the art, any obvious substitutions that do not depart from the concept of the present invention are within the scope of protection of the present invention.

Claims

1. A high-resilience and aging-resistant TPU sports shoe sole, characterized by: It includes a TPU composite film and a TPU midsole arranged on the surface of the TPU composite film, wherein the TPU composite film is a double-layer co-extruded film made by a cast co-extrusion process of TPU particles and TPU hot-melt adhesive particles; The TPU particles include the following raw materials in parts by weight: 60-80 parts of TPU elastomer, 3-8 parts of plasticizer, 0.5-6 parts of anti-yellowing agent, 0.1-1.5 parts of lubricant and 0-10 parts of colorant; The preparation method of the TPU elastomer comprises the following steps: heating and melting polycaprolactone diol and vacuum dehydrating it, then transferring it to a reactor, raising the temperature to 90-100° C., adding 4,4-dicyclohexyltoluene diisocyanate in batches under a nitrogen atmosphere, adding a small amount of an organotin catalyst to carry out a prepolymerization reaction after the temperature stabilizes, and then adding a chain extender and carbodiimide to carry out a chain extension reaction after completion, and then transferring it to a mold for curing and demolding to obtain the TPU elastomer; The TPU particles also include 12-20 parts of foamed particles; The preparation method of the foamed beads is specifically as follows: 5-8 parts of polyborosiloxane and 0.3-1 part of a compatibilizer are uniformly mixed and added to an internal mixer; 50-60 parts of ethylene-vinyl acetate copolymer, 30-40 parts of a polyolefin elastomer, 0.1-0.5 parts of a coupling agent and 0.5-3 parts of a filler are added thereto; the mixture is first heated to 80° C. for preheating and stirring; then the mixture is heated to 120-125° C., 0.5-1 parts of a cross-linking agent and 2-4 parts of a foaming agent are added and stirred continuously to obtain an internally mixed rubber material; the mixture is transferred to an open mixer at 80-90° C. for mixing, and the mixed rubber material is granulated by an extruder; the granulated rubber particles are placed in a foaming device and foamed by heating to obtain the foamed beads.

2. The high-resilience and aging-resistant TPU sports shoe sole according to claim 1, characterized in that: The plasticizer is at least one of dioctyl oxalate, dioctyl sebacic acid, epoxy fatty acid methyl ester, and propylene glycol adipate polyester.

3. The high-resilience and aging-resistant TPU sports shoe sole according to claim 1, characterized in that: The lubricant is at least one of amino silicone oil, zinc stearate, and stearamide.

4. The high-resilience and aging-resistant TPU sports shoe sole according to claim 1, characterized in that: The anti-yellowing agent is at least one of a hindered amine light stabilizer, an ultraviolet absorber, and an antioxidant.

5. The method for preparing the high-resilience and aging-resistant TPU sports shoe sole according to claim 1, characterized in that: The method comprises the following preparation steps: (1) Take the TPU composite film and press it into the desired shape through a mold to obtain a TPU outsole; (2) placing the TPU outsole obtained in step (1) into the reserved TPU outsole position in the secondary hot pressing mold, and then placing the TPU midsole; (3) The TPU outsole and the TPU midsole are formed into one piece by first performing a hot pressing treatment on the secondary hot pressing mold and then performing a cold pressing treatment, thereby obtaining the TPU sports shoe bottom sheet.

6. The method for preparing the high-resilience and aging-resistant TPU sports shoe sole according to claim 5, characterized in that: In step (3), the temperature of the hot pressing treatment is 150-160°C, and the time is 300-500s; the temperature of the cold pressing treatment is 35-37°C, and the time is 400-600s.

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