EVA (Ethylene Vinyl Acetate) foaming material, preparation method and application thereof

Abstract

The invention relates to the technical field of EVA foaming materials, in particular to an EVA foaming material and a preparation method and application thereof, and the preparation method comprises the following steps: weighing raw materials according to parts by weight, mixing for 5-8 minutes in a mixing mill at the mixing temperature of 85 DEG C, obtaining a mixed sheet after the mixing is finished, foaming in a vulcanizing machine, and obtaining the EVA foaming material after the foaming is finished. According to the EVA foaming material disclosed by the invention, EVA is matched with the antistatic agent, the stearic acid, the calcium stearate, the cross-linking agent and the foaming agent for mixing and foaming treatment, meanwhile, beta-cyclodextrin-silane combination is added, and the aluminum hydroxide agent based on end group silicone oil modification and the aluminum hydroxide agent are blended, matched and co-synergized, so that the prepared EVA foaming material has the advantages that the foaming effect is good under the low-density condition, and the foaming effect is good. The antistatic property and the non-slip property of the product are optimized and improved, and meanwhile, the elasticity and the fracture property of the product are obviously improved under the aging condition of the product.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of EVA foaming material, in particular to an EVA foaming material, a preparation method and application thereof. BACKGROUND

[0002] EVA foaming material is widely used in shoe materials due to its excellent performance. With the increasing demand of consumers for the performance of shoe products, EVA foaming material has broad development prospects in the future shoe material market. The existing EVA foaming material has poor antistatic property. In order to add an antistatic agent to optimize the antistatic property, interface problems between raw materials are prone to occur, which in turn affects the slip resistance of the product. In addition, the addition of the antistatic agent and other fillers also affects the density of the product. It is difficult to improve the antistatic property and slip resistance of the product under the condition of low density. In addition, the product has poor aging stability. Under aging conditions, the elasticity and breaking property of the product have a significant deterioration trend, which further affects the performance of the product. SUMMARY

[0003] In view of the defects of the prior art, the purpose of the present application is to provide an EVA foaming material, a preparation method and application thereof to solve the problems raised in the background.

[0004] The technical problem solved by the present application adopts the following technical scheme: The present application provides a preparation method of an EVA foaming material, comprising the following steps: Step one: weigh the raw materials according to the weight parts: 75-85 parts of EVA, 5-8 parts of an antistatic agent, 11-13 parts of an additive based on a combination of beta-cyclodextrin-silane, 5-8 parts of an aluminum hydroxide agent based on end-silicone oil modification, 2-3 parts of stearic acid, 3-5 parts of calcium stearate, 0.5-0.7 parts of a crosslinking agent and 2-3 parts of a foaming agent; Step two: sequentially add the above raw materials to a mixing machine for mixing for 5-8 minutes, and the mixing temperature is 85°C. After mixing, a mixed sheet is obtained; Step three: foaming treatment of the mixed sheet in a vulcanizing machine. After foaming, an EVA foaming material is obtained.

[0005] Preferably, the temperature of the foaming treatment is 175-180°C, the pressure is 15-20 MPa, and the time is 5-8 minutes; the crosslinking agent is cumene hydroperoxide; the foaming agent is azodicarbonamide; and the antistatic agent is composed of graphene and carbon fiber in a weight ratio of 3:2.

[0006] Preferably, the preparation method of the additive based on the combination of beta-cyclodextrin-silane is as follows: S11: 2-5 parts by weight of ethanol solvent, 5-8 parts by weight of sodium citrate solution and 1-2 parts by weight of trimethoxysilane are uniformly blended to obtain a silane solution; S12: The nanocellulose, beta-cyclodextrin and silane solution are uniformly blended and stirred according to a weight ratio of 3:(4-6):(5-8) to obtain a beta-cyclodextrin-silane modified body; S13: A hollow glass microsphere-based additive body is prepared to obtain a hollow glass microsphere-based additive body; S14: The hollow glass microsphere-based additive body and the beta-cyclodextrin-silane modified body are ball milled according to a weight ratio of 7:(3-5), and after ball milling, are filtered and dried to obtain a beta-cyclodextrin-silane combined additive.

[0007] Preferably, the preparation method of the hollow glass microsphere-based additive body is as follows: S13a: The hollow glass microspheres are preheated at 55-60°C for 1h to obtain preheated hollow glass microspheres; tetrabutyl titanate, acetone and methyl orthosilicate and triethanolamine are uniformly blended according to a weight ratio of (5-7):(13-15):(2-3):2 to obtain a composite modifier; S13b: The preheated hollow glass microspheres and the composite modifier are ultrasonically treated according to a weight ratio of (5-8):15, and after ultrasonic treatment, are filtered and dried to obtain a hollow glass microsphere-based additive body.

[0008] Preferably, the mass fraction of the sodium citrate solution is 5-8%; the ultrasonic power in S13b is 350-400W, and the ultrasonic treatment time is 1h; the ball milling speed in S14 is 1000-1200r / min, and the ball milling time is 2h.

[0009] Preferably, the preparation method of the end group silicone oil modified aluminum hydroxide agent is as follows: S101: Tris-HCL buffer solution and ethanol aqueous solution are uniformly blended according to a weight ratio of 3:(5-7) to obtain a Tris-alcohol solution; Then, aluminum hydroxide, tannic acid and the Tris-alcohol solution are uniformly blended according to a weight ratio of (3-5):2:(5-8) to obtain a modified aluminum hydroxide agent; S102: 5-8% of a siloxane modifier based on the total weight of the end group silicone oil and 18-22% of the modified aluminum hydroxide agent based on the total weight of the end group silicone oil are added to the end group silicone oil and stirred, and after stirring, are filtered and dried to obtain an end group silicone oil modified aluminum hydroxide agent.

[0010] Preferably, the hydrogen content of the end group silicone oil is 1.0-1.5%; and the siloxane modifier is gamma-aminopropyl triethoxysilane.

[0011] Preferably, the mass fraction of the aqueous ethanol solution is 55-75%; the pH value of the Tris-HCL buffer solution is 7.5-8.2; the stirring temperature of the stirring treatment is 50-55 DEG C, the stirring speed is 450-500 r / min, and the stirring time is 1 h.

[0012] The application further provides an EVA foaming material prepared by the preparation method of the EVA foaming material.

[0013] The application further provides an application of the EVA foaming material.

[0014] Compared with the prior art, the application has the following beneficial effects: The EVA foaming material is prepared by mixing and foaming EVA with antistatic agent, stearic acid, calcium stearate, crosslinking agent and foaming agent, and further adding both the additive based on the combination of beta-cyclodextrin-silane and the aluminum hydroxide agent based on the modification of end-silicone oil to improve the antistatic property and the skid resistance of the product under the condition of low density, and the elasticity and the breaking performance of the product under the aging condition are obviously improved. The additive based on the combination of beta-cyclodextrin-silane is prepared by mixing and blending nanocellulose, beta-cyclodextrin and silane liquid to form a beta-cyclodextrin-silane modified body, the nanocellulose is used as a base material, the beta-cyclodextrin has the effect of being organic and inorganic, and can play the bridging role of inorganic and organic in the system, the silane liquid is used as a system interface agent to enhance the interface effect between raw materials, the hollow glass microsphere is preheated, and then is mixed with tetrabutyl titanate, acetone, methyl silicate and triethanolamine to form a composite improved material, and then is subjected to ultrasonic treatment, the raw materials are mixed and blended, and are improved through mutual cooperation, the hollow glass microsphere is used as a base system, and then is improved and optimized by the beta-cyclodextrin-silane modified body, so that the additive based on the combination of beta-cyclodextrin-silane enhances the interface connection between raw materials in the system, optimizes the antistatic property and the skid resistance of the product under the condition of low density, improves the elasticity and the breaking performance of the product, and realizes the coordinated improvement of performance. The aluminum hydroxide agent based on the modification of end-silicone oil is prepared by mixing and stirring end-silicone oil, siloxane modifier and modified aluminum hydroxide agent, the modified aluminum hydroxide agent is prepared by mixing and optimizing aluminum hydroxide, tannic acid and Tris-alcohol solution, the raw materials are mixed and blended, and are improved through mutual cooperation and optimization, so that the aluminum hydroxide agent based on the modification of end-silicone oil strengthens the additive based on the combination of beta-cyclodextrin-silane in the system, and the product is further improved. DETAILED DESCRIPTION

[0015] With reference to the specific embodiments below, the technical solutions in the embodiments of the present application will be described clearly and completely. Obviously, the described embodiments are only a part of the embodiments of the present application, rather than all the embodiments. Based on the embodiments in the present application, all other embodiments obtained by those of ordinary skill in the art without creative work fall within the protection scope of the present application.

[0016] The preparation method of the EVA foaming material in the embodiment includes the following steps: Step one: weigh the raw materials according to the weight parts: 75-85 parts of EVA, 5-8 parts of antistatic agent, 11-13 parts of the additive based on the combination of beta-cyclodextrin-silane, 5-8 parts of the aluminum hydroxide agent based on the modification of end-silicone oil, 2-3 parts of stearic acid, 3-5 parts of calcium stearate, 0.5-0.7 parts of crosslinking agent, and 2-3 parts of foaming agent; Step two: sequentially add the above raw materials into a mixing machine for mixing for 5-8 minutes, and the mixing temperature is 85℃. After the mixing is completed, a mixed sheet is obtained; Step three: the mixed sheet is foamed in a vulcanizing machine, and the EVA foaming material is obtained after the foaming is completed.

[0017] The foaming temperature of the embodiment is 175-180℃, the pressure is 15-20MPa, and the time is 5-8 minutes; the crosslinking agent is cumene hydroperoxide; the foaming agent is azodicarbonamide; and the antistatic agent is composed of graphene and carbon fiber according to a weight ratio of 3:2.

[0018] The preparation method of the additive based on the combination of beta-cyclodextrin-silane in the embodiment is as follows: S11: uniformly blend 2-5 parts by weight of ethanol solvent, 5-8 parts by weight of sodium citrate solution, and 1-2 parts by weight of trimethoxysilane to obtain a silane liquid; S12: uniformly blend and stir the nanocellulose, beta-cyclodextrin, and the silane liquid according to a weight ratio of 3:(4-6):(5-8) to obtain a beta-cyclodextrin-silane modified body; S13: prepare an additive based on hollow glass microbeads to obtain an additive based on hollow glass microbeads; S14: ball mill the additive based on hollow glass microbeads and the beta-cyclodextrin-silane modified body according to a weight ratio of 7:(3-5), and after the ball milling is completed, perform suction filtration and drying to obtain the additive based on the combination of beta-cyclodextrin-silane.

[0019] The preparation method of the additive based on hollow glass microbeads in the embodiment is as follows: S13a: preheat the hollow glass microspheres at 55-60℃ for 1h to obtain preheated hollow glass microspheres; blend tetrabutyl titanate, acetone, and methyl orthosilicate, and triethanolamine according to the weight ratio (5-7):(13-15):(2-3):2 to obtain a composite modifier; S13b: ultrasonically treat the preheated hollow glass microspheres and the composite modifier according to the weight ratio (5-8):15, and after ultrasonic treatment, perform suction filtration and drying to obtain the hollow glass microsphere-based additive.

[0020] In this embodiment, the mass fraction of the sodium citrate solution is 5-8%; the ultrasonic power in the ultrasonic treatment in S13b is 350-400W, and the ultrasonic treatment lasts for 1h; and the ball milling speed in the ball milling treatment in S14 is 1000-1200r / min, and the ball milling lasts for 2h.

[0021] The preparation method of the aluminum hydroxide agent based on end group silicone oil modification in this embodiment is as follows: S101: blend Tris-HCL buffer and an ethanol aqueous solution according to the weight ratio 3:(5-7) to obtain a Tris-alcohol solution; Then, blend aluminum hydroxide, tannic acid, and the Tris-alcohol solution according to the weight ratio (3-5):2:(5-8) to obtain a modified aluminum hydroxide agent. S102: add 5-8% of the total weight of the end group silicone oil of a siloxane modifier and 18-22% of the total weight of the end group silicone oil of the modified aluminum hydroxide agent to the end group silicone oil, and perform stirring treatment, and after stirring, perform suction filtration and drying to obtain the aluminum hydroxide agent based on end group silicone oil modification.

[0022] The hydrogen content of the end group silicone oil in this embodiment is 1.0-1.5%; and the siloxane modifier is γ-aminopropyl triethoxysilane.

[0023] The mass fraction of the ethanol aqueous solution in this embodiment is 55-75%; the pH value of the Tris-HCL buffer is 7.5-8.2; the stirring temperature in the stirring treatment is 50-55℃, the stirring speed is 450-500r / min, and the stirring lasts for 1h.

[0024] An EVA foaming material is prepared by the preparation method of the EVA foaming material.

[0025] The EVA foaming material is applied to shoes.

[0026] Embodiment 1: a preparation method of an EVA foaming material, including the following steps: Step 1: Weigh the raw materials according to the following parts by weight: 75 parts EVA, 5 parts antistatic agent, 11 parts additive based on β-cyclodextrin-silane combination, 5 parts aluminum hydroxide agent based on end-group silicone oil modification, 2 parts stearic acid, 3 parts calcium stearate, 0.5 parts crosslinking agent and 2 parts foaming agent; Step 2: Add the ingredients sequentially to the mixer and mix for 5 minutes at a mixing temperature of 85℃. After mixing, the mixed sheet is obtained. Step 3: Foam the mixed sheets in a vulcanizing machine. Once foaming is complete, you will obtain EVA foam material.

[0027] In this embodiment, the foaming treatment temperature is 175℃, the pressure is 15MPa, and the time is 5min; the crosslinking agent is diisopropylbenzene oxide; the foaming agent is azodicarbonamide; and the antistatic agent is composed of graphene and carbon fiber in a weight ratio of 3:2.

[0028] The preparation method of the additive based on β-cyclodextrin-silane combination in this embodiment is as follows: S11: Mix 2 parts by weight of ethanol solvent, 5 parts by weight of sodium citrate solution and 1 part by weight of trimethoxysilane evenly to obtain silane solution; S12: Nanocellulose, β-cyclodextrin, and silane solution are mixed and stirred thoroughly at a weight ratio of 3:4:5 to obtain β-cyclodextrin-silane modified body; S13: Prepare an additive based on hollow glass microspheres to obtain an additive based on hollow glass microspheres; S14: The additive based on hollow glass microspheres and the β-cyclodextrin-silane modified body were ball-milled at a weight ratio of 7:3. After ball milling, the mixture was filtered and dried to obtain the additive based on the β-cyclodextrin-silane combination.

[0029] The preparation method of the hollow glass microsphere-based additive in this embodiment is as follows: S13a: Hollow glass microspheres are preheated at 55°C for 1 hour to obtain preheated hollow glass microspheres; tetrabutyl titanate, acetone, methyl orthosilicate and triethanolamine are mixed evenly in a weight ratio of 5:13:2:2 to obtain composite modified material. S13b: The preheated hollow glass microspheres and the composite modified material are ultrasonically treated at a weight ratio of 5:15. After ultrasonic treatment, the mixture is filtered and dried to obtain the additive based on hollow glass microspheres.

[0030] In this embodiment, the sodium citrate solution has a mass fraction of 5%; the ultrasonic power in S13b is 350W, and the ultrasonic treatment lasts for 1 hour; the ball milling speed in S14 is 1000 r / min, and the ball milling lasts for 2 hours.

[0031] The preparation method of the aluminum hydroxide agent based on end-group silicone oil modification in this embodiment is as follows: S101: Mix Tris-HCl buffer and aqueous ethanol solution thoroughly at a weight ratio of 3:5 to obtain Tris-ethanol solution; Then, aluminum hydroxide, tannic acid, and Tris-alcohol solution are mixed evenly in a weight ratio of 3:2:5 to obtain modified aluminum hydroxide agent; S102: Add 5% by weight of siloxane modifier and 18% by weight of modified aluminum hydroxide agent to the end-based silicone oil and stir. After stirring, filter and dry to obtain aluminum hydroxide agent modified based on end-based silicone oil.

[0032] The hydrogen content of the end-group silicone oil in this embodiment is 1.0%; the siloxane modifier is γ-aminopropyltriethoxysilane.

[0033] In this embodiment, the ethanol-water solution had a mass fraction of 55%; the Tris-HCl buffer had a pH of 7.5; the stirring temperature was 50°C, the stirring speed was 450 r / min, and the stirring time was 1 h.

[0034] The EVA foaming material of this embodiment is prepared by the method for preparing EVA foaming material described above.

[0035] This embodiment describes the application of EVA foam material in shoes.

[0036] Example 2: A method for preparing EVA foam material, comprising the following steps: Step 1: Weigh the raw materials according to the following parts by weight: 85 parts EVA, 8 parts antistatic agent, 13 parts additive based on β-cyclodextrin-silane combination, 8 parts aluminum hydroxide agent based on end-group silicone oil modification, 3 parts stearic acid, 5 parts calcium stearate, 0.7 parts crosslinking agent and 3 parts foaming agent; Step 2: Add the above raw materials to the mixer in sequence and mix for 8 minutes at a mixing temperature of 85℃. After mixing, the mixed sheet is obtained. Step 3: Foam the mixed sheets in a vulcanizing machine. Once foaming is complete, you will obtain EVA foam material.

[0037] In this embodiment, the foaming treatment temperature is 180℃, the pressure is 20MPa, and the time is 8min; the crosslinking agent is diisopropylbenzene oxide; the foaming agent is azodicarbonamide; and the antistatic agent is composed of graphene and carbon fiber in a weight ratio of 3:2.

[0038] The preparation method of the additive based on β-cyclodextrin-silane combination in this embodiment is as follows: S11: Mix 5 parts by weight of ethanol solvent, 8 parts by weight of sodium citrate solution and 2 parts by weight of trimethoxysilane evenly to obtain silane solution; S12: Nanocellulose, β-cyclodextrin, and silane solution are mixed and stirred thoroughly at a weight ratio of 3:6:8 to obtain β-cyclodextrin-silane modified body; S13: Prepare an additive based on hollow glass microspheres to obtain an additive based on hollow glass microspheres; S14: The additive based on hollow glass microspheres and the β-cyclodextrin-silane modified body were ball-milled at a weight ratio of 7:5. After ball milling, the mixture was filtered and dried to obtain the additive based on the β-cyclodextrin-silane combination.

[0039] The preparation method of the hollow glass microsphere-based additive in this embodiment is as follows: S13a: Hollow glass microspheres are preheated at 60°C for 1 hour to obtain preheated hollow glass microspheres; tetrabutyl titanate, acetone, methyl orthosilicate and triethanolamine are mixed evenly in a weight ratio of 7:15:3:2 to obtain composite modified material. S13b: The preheated hollow glass microspheres and the composite modified material are ultrasonically treated at a weight ratio of 8:15. After ultrasonic treatment, the mixture is filtered and dried to obtain the additive based on hollow glass microspheres.

[0040] In this embodiment, the sodium citrate solution has a mass fraction of 8%; the ultrasonic power in S13b is 400W, and the ultrasonic treatment lasts for 1 hour; the ball milling speed in S14 is 1200 r / min, and the ball milling lasts for 2 hours.

[0041] The preparation method of the aluminum hydroxide agent based on end-group silicone oil modification in this embodiment is as follows: S101: Mix Tris-HCl buffer and aqueous ethanol solution thoroughly at a weight ratio of 3:7 to obtain Tris-ethanol solution; Then, aluminum hydroxide, tannic acid, and Tris-alcohol solution are mixed evenly in a weight ratio of 5:2:8 to obtain modified aluminum hydroxide agent; S102: Add 8% by weight of siloxane modifier and 22% by weight of modified aluminum hydroxide agent to the end-based silicone oil and stir. After stirring, filter and dry to obtain aluminum hydroxide agent modified based on end-based silicone oil.

[0042] The hydrogen content of the end-group silicone oil in this embodiment is 1.5%; the siloxane modifier is γ-aminopropyltriethoxysilane.

[0043] In this embodiment, the ethanol-water solution had a mass fraction of 75%; the Tris-HCl buffer had a pH of 8.2; the stirring temperature was 55°C, the stirring speed was 500 r / min, and the stirring time was 1 h.

[0044] The EVA foaming material of this embodiment is prepared by the method for preparing EVA foaming material described above.

[0045] This embodiment describes the application of EVA foam material in shoes.

[0046] Example 3: A method for preparing EVA foam material, comprising the following steps: Step 1: Weigh the raw materials according to the following parts by weight: 80 parts EVA, 6.5 parts antistatic agent, 12 parts additive based on β-cyclodextrin-silane combination, 6.5 parts aluminum hydroxide agent based on end-group silicone oil modification, 2.5 parts stearic acid, 4 parts calcium stearate, 0.6 parts crosslinking agent and 2.5 parts foaming agent; Step 2: Add the above raw materials to the mixer in sequence and mix for 6.5 minutes at a mixing temperature of 85℃. After mixing, the mixed sheet is obtained. Step 3: Foam the mixed sheets in a vulcanizing machine. Once foaming is complete, you will obtain EVA foam material.

[0047] In this embodiment, the foaming treatment temperature is 178°C, the pressure is 18 MPa, and the time is 6.5 min; the crosslinking agent is diisopropylbenzene oxide; the foaming agent is azodicarbonamide; and the antistatic agent is composed of graphene and carbon fiber in a weight ratio of 3:2.

[0048] The preparation method of the additive based on β-cyclodextrin-silane combination in this embodiment is as follows: S11: Mix 3.5 parts by weight of ethanol solvent, 6.5 parts by weight of sodium citrate solution and 1.5 parts by weight of trimethoxysilane evenly to obtain silane solution; S12: Nanocellulose, β-cyclodextrin, and silane solution are mixed and stirred thoroughly at a weight ratio of 3:5:6.5 to obtain β-cyclodextrin-silane modified body; S13: Prepare an additive based on hollow glass microspheres to obtain an additive based on hollow glass microspheres; S14: The additive based on hollow glass microspheres and the β-cyclodextrin-silane modified body were ball-milled at a weight ratio of 7:4. After ball milling, the mixture was filtered and dried to obtain the additive based on the β-cyclodextrin-silane combination.

[0049] The preparation method of the hollow glass microsphere-based additive in this embodiment is as follows: S13a: Hollow glass microspheres are preheated at 58°C for 1 hour to obtain preheated hollow glass microspheres; tetrabutyl titanate, acetone, methyl orthosilicate and triethanolamine are mixed evenly in a weight ratio of 6:14:2.5:2 to obtain composite modified material. S13b: The preheated hollow glass microspheres and the composite modified material are ultrasonically treated at a weight ratio of 6.5:15. After ultrasonic treatment, the mixture is filtered and dried to obtain the additive based on hollow glass microspheres.

[0050] In this embodiment, the sodium citrate solution has a mass fraction of 6.5%; the ultrasonic power in S13b is 375W, and the ultrasonic treatment lasts for 1 hour; the ball milling speed in S14 is 1100 r / min, and the ball milling lasts for 2 hours.

[0051] The preparation method of the aluminum hydroxide agent based on end-group silicone oil modification in this embodiment is as follows: S101: Mix Tris-HCl buffer and aqueous ethanol solution at a weight ratio of 3:6 to obtain Tris-ethanol solution; Then, aluminum hydroxide, tannic acid, and Tris-alcohol solution are mixed evenly in a weight ratio of 4:2:6.5 to obtain modified aluminum hydroxide agent; S102: Add 6.5% of the total weight of the end-based silicone oil as a siloxane modifier and 20% of the total weight of the end-based silicone oil as a modified aluminum hydroxide agent to the end-based silicone oil and stir. After stirring, filter and dry to obtain an aluminum hydroxide agent modified based on the end-based silicone oil.

[0052] The hydrogen content of the end-group silicone oil in this embodiment is 1.2%; the siloxane modifier is γ-aminopropyltriethoxysilane.

[0053] In this embodiment, the ethanol-water solution had a mass fraction of 60%; the Tris-HCl buffer had a pH of 7.9; the stirring temperature was 52.5℃, the stirring speed was 475 r / min, and the stirring time was 1 h.

[0054] The EVA foaming material of this embodiment is prepared by the method for preparing EVA foaming material described above.

[0055] This embodiment describes the application of EVA foam material in shoes.

[0056] Comparative Example 1: Unlike Example 3, no additives based on the β-cyclodextrin-silane combination were added.

[0057] Comparative Example 2: Unlike Example 3, no β-cyclodextrin-silane modifier was added in the preparation of the additive based on the β-cyclodextrin-silane combination.

[0058] Comparative Example 3: Unlike Example 3, nanocellulose and β-cyclodextrin were not added in the preparation of the β-cyclodextrin-silane modified body.

[0059] Comparative Example 4: Unlike Example 3, no additives based on hollow glass microspheres were added in the preparation of the β-cyclodextrin-silane modified body.

[0060] Comparative Example 5: Unlike Example 3, no preheated hollow glass microspheres were added in the preparation of the additive based on hollow glass microspheres.

[0061] Comparative Example 6: Unlike Example 3, no composite improvement material was added in the preparation of the additive based on hollow glass microspheres.

[0062] Comparative Example 7: Unlike Example 3, the improved composite material did not contain tetrabutyl titanate or methyl orthosilicate.

[0063] Comparative Example 8: Unlike Example 3, aluminum hydroxide based on end-group silicone oil modification was not added.

[0064] Comparative Example 9: Unlike Example 3, no siloxane modifier was added in the preparation of the aluminum hydroxide agent based on end-group silicone oil modification.

[0065] Comparative Example 10: Unlike Example 3, no modified aluminum hydroxide agent was added in the preparation of the aluminum hydroxide agent based on end-group silicone oil modification.

[0066] Comparative Example 11: Unlike Example 3, aluminum hydroxide and tannic acid were not added in the preparation of the modified aluminum hydroxide agent.

[0067] Comparative Example 12: Unlike Example 3, the Tris-HCl buffer was not added to the Tris-alcohol solution in the preparation of the modified aluminum hydroxide agent.

[0068] The products of Examples 1-3 and Comparative Examples 1-12 were subjected to performance tests for density, antistatic properties and antislip properties. The test results are shown in Table 1.

[0069] Table 1. Test results of product density, antistatic properties, and antislip properties in Examples 1-3 and Comparative Examples 1-12:

[0070] As can be seen from Comparative Examples 1-12 and Examples 1-3, the product of Example 3 has excellent density and dry friction coefficient, and excellent volume resistivity. The product can achieve coordinated improvement in low density, anti-slip and antistatic properties. The product does not contain any additives based on β-cyclodextrin-silane combination or aluminum hydroxide agent modified by end-group silicone oil. The performance of the product deteriorates to varying degrees. The product of Example 3 of the present invention has the most significant performance.

[0071] The products of Examples 1-3 and Comparative Examples 1-12 were tested for elasticity and fracture properties under normal conditions and aging resistance conditions. The aging resistance conditions were to age the products at 70°C and 100% relative humidity for 168 hours, in accordance with the standard GB / T3903.7-2019 "Aging Treatment of Whole Footwear Test Methods"; the test results are shown in Table 2.

[0072] Table 2. Test results of elasticity and fracture properties of the products from Examples 1-3 and Comparative Examples 1-12:

[0073] As shown in Table 2, the product of Example 3, in addition to having low density, anti-slip and antistatic properties, also has excellent elongation at break and elastic properties, as well as significant anti-aging stability. As can be seen from Comparative Examples 1-12 and Example 3, the performance of the product deteriorates significantly when neither of the additives based on β-cyclodextrin-silane combination nor the aluminum hydroxide agent based on end-group silicone oil modification is added. The product's performance is most significantly improved when both are used in combination. In the preparation of additives based on β-cyclodextrin-silane combination, no β-cyclodextrin-silane modifier was added; in the preparation of β-cyclodextrin-silane modifier, no nanocellulose or β-cyclodextrin was added; in the preparation of β-cyclodextrin-silane modifier, no hollow glass microsphere-based additive was added; in the preparation of hollow glass microsphere-based additive, no preheated hollow glass microspheres were added; in the preparation of hollow glass microsphere-based additive, no composite improver was added; and in the composite improver, no tetrabutyl titanate or methyl orthosilicate was added. The performance of the products all showed a trend of deterioration. An additive based on hollow glass microspheres, made by combining a specific composite modified material with preheated hollow glass microspheres, and an additive based on β-cyclodextrin-silane modified material, are used together to produce an additive with the most significant performance effect. In the preparation of aluminum hydroxide agents modified with end-group silicone oil, no siloxane modifier was added. Similarly, in the preparation of modified aluminum hydroxide agents, no modified aluminum hydroxide was added. In the preparation of modified aluminum hydroxide agents, no aluminum hydroxide or tannic acid was added. Furthermore, in the preparation of modified aluminum hydroxide agents, no Tris-HCl buffer was added to the Tris-alcohol solution. All these methods resulted in a deterioration in product performance. Only the modified aluminum hydroxide agent prepared using the method of this invention, combined with a siloxane modifier, produced as an end-group silicone oil-modified aluminum hydroxide agent, exhibited the most significant performance improvement. Moreover, the preparation method of the modified aluminum hydroxide agent is unique, and other methods are not as effective as those of this invention.

[0074] It will be apparent to those skilled in the art that the present invention is not limited to the details of the exemplary embodiments described above, and that the invention can be implemented in other specific forms without departing from the spirit or essential characteristics of the invention. Therefore, the embodiments should be considered in all respects as exemplary and non-limiting, and the scope of the invention is defined by the appended claims rather than the foregoing description. Thus, it is intended that all variations falling within the meaning and scope of equivalents of the claims be included within the present invention.

[0075] Furthermore, it should be understood that although this specification describes embodiments, not every embodiment contains only one independent technical solution. This narrative style is merely for clarity. Those skilled in the art should consider the specification as a whole, and the technical solutions in each embodiment can also be appropriately combined to form other embodiments that can be understood by those skilled in the art.

Claims

1. A method for preparing EVA foam material, characterized in that, Includes the following steps: Step 1: Weigh the raw materials according to the following parts by weight: 75-85 parts EVA, 5-8 parts antistatic agent, 11-13 parts additive based on β-cyclodextrin-silane combination, 5-8 parts aluminum hydroxide agent based on end-group silicone oil modification, 2-3 parts stearic acid, 3-5 parts calcium stearate, 0.5-0.7 parts crosslinking agent and 2-3 parts foaming agent; The preparation method of the additive based on β-cyclodextrin-silane combination is as follows: S11: Mix 2-5 parts by weight of ethanol solvent, 5-8 parts by weight of sodium citrate solution and 1-2 parts by weight of trimethoxysilane evenly to obtain silane solution; S12: Nanocellulose, β-cyclodextrin, and silane solution are mixed and stirred thoroughly at a weight ratio of 3:(4-6):(5-8) to obtain β-cyclodextrin-silane modified body; S13: Prepare an additive based on hollow glass microspheres to obtain an additive based on hollow glass microspheres; S14: The additive based on hollow glass microspheres and the β-cyclodextrin-silane modified body were ball-milled at a weight ratio of 7:(3-5). After ball milling, the mixture was filtered and dried to obtain the additive based on the β-cyclodextrin-silane combination. The preparation method of the aluminum hydroxide agent based on end-group silicone oil modification is as follows: S101: Mix Tris-HCl buffer and aqueous ethanol solution at a weight ratio of 3:(5-7) thoroughly to obtain Tris-ethanol solution; Then, aluminum hydroxide, tannic acid, and Tris-alcohol solution are mixed evenly in a weight ratio of (3-5):2:(5-8) to obtain modified aluminum hydroxide agent; S102: Add 5-8% of the total weight of the end-based silicone oil as a siloxane modifier and 18-22% of the total weight of the end-based silicone oil as a modified aluminum hydroxide agent to the end-based silicone oil and stir. After stirring, filter and dry to obtain an aluminum hydroxide agent modified based on the end-based silicone oil. Step 2: Add the above raw materials to the mixer in sequence and mix for 5-8 minutes at a mixing temperature of 85℃. After mixing, the mixed sheet is obtained. Step 3: Foam the mixed sheets in a vulcanizing machine. Once foaming is complete, you will obtain EVA foam material.

2. The method for preparing an EVA foam material according to claim 1, characterized in that, The foaming process is carried out at a temperature of 175-180℃, a pressure of 15-20MPa, and a time of 5-8min.

3. The method for preparing an EVA foam material according to claim 1, characterized in that, The crosslinking agent is dicumyl oxide; the foaming agent is azodicarbonamide; and the antistatic agent is composed of graphene and carbon fiber in a weight ratio of 3:

2.

4. The method for preparing an EVA foam material according to claim 1, characterized in that, The preparation method of the hollow glass microsphere-based additive is as follows: S13a: Preheat hollow glass microspheres at 55-60℃ for 1 hour to obtain preheated hollow glass microspheres; mix tetrabutyl titanate, acetone, methyl orthosilicate and triethanolamine in a weight ratio of (5-7):(13-15):(2-3):2 to obtain composite improved material. S13b: The preheated hollow glass microspheres and composite modified material are ultrasonically treated at a weight ratio of (5-8):

15. After ultrasonic treatment, the mixture is filtered and dried to obtain an additive based on hollow glass microspheres.

5. The method for preparing an EVA foam material according to claim 4, characterized in that, The sodium citrate solution has a mass fraction of 5-8%; the ultrasonic power for ultrasonic treatment in S13b is 350-400W, and the ultrasonic treatment lasts for 1 hour; the ball milling speed for ball milling treatment in S14 is 1000-1200 r / min, and the ball milling lasts for 2 hours.

6. The method for preparing an EVA foam material according to claim 1, characterized in that, The stirring temperature for the stirring process is 50-55℃, the stirring speed is 450-500 r / min, and the stirring time is 1 hour.

7. The method for preparing an EVA foam material according to claim 1, characterized in that, The hydrogen content of the end-group silicone oil is 1.0-1.5%; the siloxane modifier is γ-aminopropyltriethoxysilane.

8. The method for preparing an EVA foam material according to claim 1, characterized in that, The ethanol-water solution has a mass fraction of 55-75%; the pH of the Tris-HCl buffer solution is 7.5-8.

2.

9. An EVA foam material, characterized in that, It is prepared by the method for preparing an EVA foam material as described in any one of claims 1 to 8.

10. An application of an EVA foam material, characterized in that, The EVA foam material as described in claim 9 is applied to shoes.

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