High-elasticity wear-resistant EVA (Ethylene Vinyl Acetate) sole material and preparation process thereof

Abstract

The invention relates to the technical field of sole materials, in particular to a high-elasticity wear-resistant EVA sole material and a preparation process thereof. The sole material is prepared from the following raw materials in parts by weight: 50 to 60 parts of ethylene-vinyl acetate copolymer, 10 to 20 parts of ethylene-octylene copolymer, 20 to 30 parts of thermoplastic elastomer, 5 to 10 parts of modified zinc oxide whisker, 2 to 5 parts of talcum powder, 1 to 3 parts of zinc stearate, 0.5 to 1.5 parts of stearic acid, 2 to 5 parts of foaming agent, 1 to 2 parts of cross-linking agent and 0.3 to 0.8 part of antioxidant. The high-elasticity wear-resistant EVA sole material prepared by the invention has good wear resistance and elasticity, and good strength can be ensured while the comfort is improved.

Description

Technical Field

[0001] This invention relates to the field of shoe sole material technology, specifically to a high-elasticity, wear-resistant EVA shoe sole material and its preparation process. Background Technology

[0002] As people's demands for comfort and functionality in various types of shoes, such as athletic shoes and casual shoes, continue to increase, the research and development and improvement of sole materials have become crucial for the development of the footwear industry. EVA (ethylene-vinyl acetate copolymer), as a high-performance polymer material, is widely used in the field of sole materials due to its advantages such as softness, good elasticity, chemical resistance, and good processing performance.

[0003] However, traditional EVA sole materials still have limitations in terms of high elasticity and abrasion resistance, and cannot fully meet consumers' needs for shoes in different usage scenarios. After prolonged use or exposure to significant pressure, the elasticity of some EVA sole materials gradually decreases, failing to maintain good rebound performance and affecting wearing comfort and agility during movement. Furthermore, frequent friction between the sole and the ground during daily walking or exercise easily leads to wear, reducing the sole's anti-slip and support performance, and shortening the shoe's lifespan. Under different environmental conditions, such as high temperature, low temperature, and humidity, EVA sole materials may harden, become brittle, and age, further affecting their performance and appearance.

[0004] Therefore, developing a highly elastic and wear-resistant EVA sole material and its preparation process is of great significance. Summary of the Invention

[0005] The purpose of this invention is to provide a highly elastic and wear-resistant EVA shoe sole material and its preparation process to solve the problems raised in the prior art.

[0006] To achieve the above objectives, the present invention provides the following technical solution:

[0007] A highly elastic and wear-resistant EVA shoe sole material, wherein the shoe sole material is composed of the following raw materials in parts by weight: 50-60 parts of ethylene-vinyl acetate copolymer, 10-20 parts of ethylene-octene copolymer, 20-30 parts of thermoplastic elastomer, 5-10 parts of modified zinc oxide whiskers, 2-5 parts of talc, 1-3 parts of zinc stearate, 0.5-1.5 parts of stearic acid, 2-5 parts of foaming agent, 1-2 parts of crosslinking agent, and 0.3-0.8 parts of antioxidant.

[0008] Furthermore, the method for preparing the modified zinc oxide whiskers includes the following steps:

[0009] Step 1: Mix zinc oxide whiskers, anhydrous ethanol, deionized water and 3-aminopropyltriethoxysilane, sonicate for 30-50 min, react at 60-70℃ for 4-6 h, and after centrifugation, washing and drying, obtain aminated zinc oxide whiskers.

[0010] Step 2: Mix aminated zinc oxide whiskers, epoxidized EVA and toluene evenly, react at 50-60℃ for 12-24h, introduce nitrogen gas, add isocyanate-terminated polybutadiene and dibutyltin dilaurate and mix evenly, react at 70-80℃ for 3-5h, cool to room temperature, filter, wash and dry to obtain modified zinc oxide whiskers.

[0011] Further, in step 1, the mass ratio of zinc oxide whiskers to anhydrous ethanol, deionized water, and 3-aminopropyltrimethoxysilane is 1:(10-12):(2-4):(0.3-0.5).

[0012] Furthermore, in step 2, the mass ratio of aminated zinc oxide whiskers, epoxidized EVA, and toluene is 1:(2-4):(10-20).

[0013] Furthermore, in step 2, the amount of terminal isocyanate-terminated polybutadiene used is 50-150% of the mass of aminated zinc oxide whiskers.

[0014] Furthermore, in step 2, the amount of dibutyltin dilaurate used is 0.1-0.3% of the mass of the aminated zinc oxide whiskers.

[0015] Further, the epoxidized EVA includes the following steps:

[0016] Step A: Mix ethylene-vinyl acetate copolymer, methanol and toluene evenly, add sodium hydroxide, react at 45-55℃ for 3-5 hours, filter, wash with methanol and vacuum dry to obtain hydroxyl-containing EVA;

[0017] Step B: Mix hydroxyl-containing EVA, gallic acid and toluene evenly, add p-toluenesulfonic acid, and react under a nitrogen atmosphere at 110-120℃ for 12-14 hours. After precipitation, filtration, washing and vacuum drying, gallic acid-grafted EVA is obtained.

[0018] Step C: Gallic acid-grafted EVA, epichlorohydrin, and benzyltriethylammonium chloride are mixed evenly and reacted at 80-90℃ under a nitrogen atmosphere for 3-5 hours. The temperature is then lowered to 50-55℃, sodium hydroxide solution is added, and the reaction continues for 2-3 hours. After filtration, washing, and drying, epoxidized EVA is obtained.

[0019] Further, in step A, the mass ratio of ethylene-vinyl acetate copolymer, methanol, toluene, and sodium hydroxide is 1:(5-10):(10-20):(0.2-0.5).

[0020] Further, in step B, the mass ratio of hydroxyl EVA, gallic acid, toluene, and p-toluenesulfonic acid is 1:(0.2-0.4):(10-20):(0.1-0.3).

[0021] Further, in step C, the mass ratio of gallic acid-grafted EVA, epichlorohydrin, benzyltriethylammonium chloride, and sodium hydroxide solution is 1:(2-3):(0.05-0.08):(0.5-1.0), and the concentration of sodium hydroxide solution is 30-40 wt%.

[0022] Furthermore, the foaming agent is azodicarbonamide.

[0023] Furthermore, the crosslinking agent is dicumyl peroxide.

[0024] A manufacturing process for a highly elastic and wear-resistant EVA shoe sole material includes the following steps:

[0025] Ethylene-vinyl acetate copolymer, ethylene-octene copolymer, thermoplastic elastomer, modified zinc oxide whiskers, talc, zinc stearate, stearic acid and antioxidant are mixed and kneaded at 100-120℃ for 20-30 minutes. Then foaming agent and crosslinking agent are added and kneaded for another 10-15 minutes. The mixture is discharged, placed in a mold, and molded by compression molding to obtain a high-elasticity and wear-resistant EVA shoe sole material.

[0026] Furthermore, the foaming molding temperature is 160-180℃, the pressure is 10-20MPa, and the holding time is 5-10min.

[0027] Compared with the prior art, the beneficial effects of the present invention are:

[0028] This invention relates to a highly elastic and wear-resistant EVA shoe sole material and its preparation process. Using ethylene-vinyl acetate (EVA) and methanol as raw materials and sodium hydroxide as a catalyst, hydroxyl-containing EVA is obtained through an alcoholysis reaction. Gallic acid, a natural phenolic acid antioxidant, is grafted onto the hydroxyl-containing EVA molecular chain through an esterification reaction under the catalysis of p-toluenesulfonic acid, resulting in gallic acid-grafted EVA. This significantly improves the material's antioxidant properties and durability, extending its service life. Using gallic acid-grafted EVA as the main raw material, epoxidized EVA is prepared through an epoxidation reaction, where the epoxy groups can play a role in subsequent crosslinking reactions.

[0029] Zinc oxide whiskers possess high hardness and wear resistance, but their optimal performance depends on uniform dispersion within the matrix to prevent agglomeration. To address this, this solution combines zinc oxide whiskers, surface-modified with silane coupling agent KH550, with epoxidized EVA. This not only improves the compatibility of the zinc oxide whiskers but also allows the hydroxyl groups generated from the ring-opening reaction of amino groups with epoxy resin to further react with the isocyanate groups of terminal isocyanate polybutadiene, forming new chemical bonds. This introduces flexible polybutadiene segments to enhance resilience and simultaneously improves the adhesion between the inorganic filler and the matrix resin. Ultimately, the prepared high-elasticity, wear-resistant EVA sole material exhibits excellent wear resistance, elasticity, and anti-aging properties, meeting the increasing performance requirements of modern consumers for sole materials and offering better service life and comfort. Detailed Implementation

[0030] The technical solutions in the embodiments of the present invention will be clearly and completely described below. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0031] In this embodiment, the ethylene-vinyl acetate copolymer is EVA 7360M with a VA content of 21%; the ethylene-octene copolymer is Dow POE 8137; the thermoplastic elastomer is DuPont TPE 4069; the zinc oxide whiskers are model JC-01, purchased from Chengdu Tianyou Jingchuang Technology Co., Ltd.; the talc powder has a particle size of 2000 mesh and is purchased from Guangdong Yongfeng Chemical Co., Ltd.; the antioxidant is MB; and the isocyanate-terminated polybutadiene is TP-1001, purchased from Jiangshan Chemical (Shanghai) Co., Ltd.

[0032] Unless otherwise specified, all the following quantities are parts by weight.

[0033] Example 1: A preparation process for a high-elasticity, wear-resistant EVA shoe sole material, comprising the following processes:

[0034] 50 parts of ethylene-vinyl acetate copolymer, 10 parts of ethylene-octene copolymer, 20 parts of thermoplastic elastomer, 5 parts of modified zinc oxide whiskers, 2 parts of talc, 1 part of zinc stearate, 0.5 parts of stearic acid and 0.3 parts of antioxidant were mixed and kneaded at 100°C for 20 minutes. Then, 2 parts of azodicarbonamide and 1 part of dicumyl peroxide were added and kneaded for another 10 minutes. The mixture was then discharged, placed in a mold, and subjected to compression molding (160°C, 10 MPa pressure, and 10 minutes) to obtain a high-elasticity and wear-resistant EVA shoe sole material.

[0035] The preparation method of modified zinc oxide whiskers includes the following steps:

[0036] Step 1: Mix 5 parts zinc oxide whiskers, 50 parts anhydrous ethanol, 10 parts deionized water and 1.5 parts 3-aminopropyltriethoxysilane, sonicate for 30 min, react at 60℃ for 4 h, and after centrifugation, washing and drying, obtain aminated zinc oxide whiskers.

[0037] Step 2: Mix 5 parts of aminated zinc oxide whiskers, 10 parts of epoxidized EVA and 50 parts of toluene evenly, react at 50°C for 12 hours, introduce nitrogen gas, add 2.5 parts of isocyanate-terminated polybutadiene and 0.005 parts of dibutyltin dilaurate and mix evenly, react at 70°C for 3 hours, cool to room temperature, filter, wash and dry to obtain modified zinc oxide whiskers;

[0038] Epoxidation of EVA includes the following steps:

[0039] Step A: Mix 10 parts of ethylene-vinyl acetate copolymer, 50 parts of methanol and 100 parts of toluene evenly, add 2 parts of sodium hydroxide, react at 45°C for 3 hours, filter, wash with methanol and vacuum dry to obtain hydroxyl-containing EVA;

[0040] Step B: Mix 10 parts of hydroxyl-containing EVA, 2 parts of gallic acid and 100 parts of toluene evenly, add 1 part of p-toluenesulfonic acid, react at 110°C under a nitrogen atmosphere for 12 hours, and after precipitation, filtration, washing and vacuum drying, gallic acid-grafted EVA is obtained.

[0041] Step C: Mix 10 parts gallic acid-grafted EVA, 20 parts epichlorohydrin and 0.5 parts benzyltriethylammonium chloride evenly, react at 80°C under a nitrogen atmosphere for 3 hours, cool down to 50°C, add 5 parts 30wt% sodium hydroxide solution, and continue to react for 2 hours. After filtration, washing and drying, epoxidized EVA is obtained.

[0042] Example 2: A preparation process for a high-elasticity, wear-resistant EVA shoe sole material, comprising the following processes:

[0043] 55 parts of ethylene-vinyl acetate copolymer, 15 parts of ethylene-octene copolymer, 25 parts of thermoplastic elastomer, 8 parts of modified zinc oxide whiskers, 3 parts of talc, 2 parts of zinc stearate, 1 part of stearic acid and 0.5 parts of antioxidant were mixed and kneaded at 110°C for 25 minutes. Then, 3 parts of azodicarbonamide and 1.5 parts of dicumyl peroxide were added and kneaded for another 12 minutes. The mixture was discharged, placed in a mold, and subjected to compression molding (170°C, 15 MPa pressure, and 7 minutes) to obtain a high-elasticity and wear-resistant EVA shoe sole material.

[0044] The preparation method of modified zinc oxide whiskers includes the following steps:

[0045] Step 1: Mix 8 parts of zinc oxide whiskers, 88 parts of anhydrous ethanol, 24 parts of deionized water and 3.2 parts of 3-aminopropyltriethoxysilane, sonicate for 40 min, react at 65℃ for 5 h, and after centrifugation, washing and drying, obtain aminated zinc oxide whiskers.

[0046] Step 2: Mix 8 parts of aminated zinc oxide whiskers, 24 parts of epoxidized EVA and 120 parts of toluene evenly, react at 55°C for 18 hours, introduce nitrogen gas, add 8 parts of isocyanate-terminated polybutadiene and 0.02 parts of dibutyltin dilaurate and mix evenly, react at 75°C for 4 hours, cool to room temperature, filter, wash and dry to obtain modified zinc oxide whiskers;

[0047] Epoxidation of EVA includes the following steps:

[0048] Step A: Mix 24 parts of ethylene-vinyl acetate copolymer, 190 parts of methanol and 360 parts of toluene evenly, add 9 parts of sodium hydroxide, react at 50°C for 4 hours, filter, wash with methanol and vacuum dry to obtain hydroxyl-containing EVA;

[0049] Step B: Mix 24 parts of hydroxyl-containing EVA, 7.2 parts of gallic acid and 360 parts of toluene evenly, add 4.8 parts of p-toluenesulfonic acid, react at 115°C under a nitrogen atmosphere for 13 hours, and after precipitation, filtration, washing and vacuum drying, gallic acid-grafted EVA is obtained.

[0050] Step C: Mix 24 parts gallic acid-grafted EVA, 60 parts epichlorohydrin and 1.5 parts benzyltriethylammonium chloride evenly, react at 85°C under a nitrogen atmosphere for 4 hours, cool to 52°C, add 20 parts 35wt% sodium hydroxide solution, and continue the reaction for 2.5 hours. After filtration, washing and drying, epoxidized EVA is obtained.

[0051] Example 3: A preparation process for a high-elasticity, wear-resistant EVA shoe sole material, comprising the following processes:

[0052] 60 parts of ethylene-vinyl acetate copolymer, 20 parts of ethylene-octene copolymer, 30 parts of thermoplastic elastomer, 10 parts of modified zinc oxide whiskers, 5 parts of talc, 3 parts of zinc stearate, 1.5 parts of stearic acid and 0.8 parts of antioxidant were mixed and kneaded at 120°C for 30 minutes. Then, 5 parts of azodicarbonamide and 2 parts of dicumyl peroxide were added and kneaded for another 15 minutes. The mixture was then discharged, placed in a mold, and subjected to compression molding (180°C, 20 MPa pressure, and 5 minutes holding time) to obtain a high-elasticity and wear-resistant EVA shoe sole material.

[0053] The preparation method of modified zinc oxide whiskers includes the following steps:

[0054] Step 1: Mix 10 parts zinc oxide whiskers, 100 parts anhydrous ethanol, 200 parts deionized water and 5 parts 3-aminopropyltriethoxysilane, sonicate for 50 min, react at 70℃ for 6 h, and after centrifugation, washing and drying, obtain aminated zinc oxide whiskers.

[0055] Step 2: Mix 10 parts of aminated zinc oxide whiskers, 40 parts of epoxidized EVA and 200 parts of toluene evenly, react at 60°C for 24 hours, introduce nitrogen gas, add 15 parts of isocyanate-terminated polybutadiene and 0.03 parts of dibutyltin dilaurate and mix evenly, react at 80°C for 5 hours, cool to room temperature, filter, wash and dry to obtain modified zinc oxide whiskers;

[0056] Epoxidation of EVA includes the following steps:

[0057] Step A: Mix 40 parts of ethylene-vinyl acetate copolymer, 400 parts of methanol and 800 parts of toluene evenly, add 20 parts of sodium hydroxide, react at 55°C for 5 hours, filter, wash with methanol and vacuum dry to obtain hydroxyl-containing EVA;

[0058] Step B: Mix 40 parts of hydroxyl-containing EVA, 20 parts of gallic acid and 800 parts of toluene evenly, add 12 parts of p-toluenesulfonic acid, react at 120°C under a nitrogen atmosphere for 14 hours, and after precipitation, filtration, washing and vacuum drying, gallic acid-grafted EVA is obtained.

[0059] Step C: Mix 40 parts gallic acid-grafted EVA, 120 parts epichlorohydrin and 3.2 parts benzyltriethylammonium chloride evenly, react at 90°C under a nitrogen atmosphere for 5 hours, cool to 55°C, add 40 parts 40wt% sodium hydroxide solution, and continue the reaction for 3 hours. After filtration, washing and drying, epoxidized EVA is obtained.

[0060] Comparative Example 1: A preparation process for a high-elasticity, abrasion-resistant EVA shoe sole material, comprising the following processes:

[0061] The preparation method of aminated zinc oxide whiskers includes the following steps:

[0062] Eight parts of zinc oxide whiskers, 88 parts of anhydrous ethanol, 24 parts of deionized water and 3.2 parts of 3-aminopropyltriethoxysilane were mixed, ultrasonically dispersed for 40 min, reacted at 65 °C for 5 h, and after centrifugation, washing and drying, aminated zinc oxide whiskers were obtained.

[0063] Compared with Example 2, Comparative Example 1 replaced the modified zinc oxide whiskers with the same mass of aminated zinc oxide whiskers, and the other steps were the same as in Example 2.

[0064] Comparative Example 2: A preparation process for a high-elasticity, wear-resistant EVA shoe sole material, comprising the following processes:

[0065] The preparation method of modified zinc oxide whiskers includes the following steps:

[0066] Step 1: Mix 8 parts of zinc oxide whiskers, 88 parts of anhydrous ethanol, 24 parts of deionized water and 3.2 parts of 3-aminopropyltriethoxysilane, sonicate for 40 min, react at 65℃ for 5 h, and after centrifugation, washing and drying, obtain aminated zinc oxide whiskers.

[0067] Step 2: Mix 8 parts of aminated zinc oxide whiskers, 24 parts of epoxidized EVA and 120 parts of toluene evenly, react at 55°C for 18 hours, cool to room temperature, filter, wash and dry to obtain modified zinc oxide whiskers;

[0068] Compared with Example 2, Comparative Example 2 did not introduce isocyanate-terminated polybutadiene, but the other steps were the same as in Example 2.

[0069] Comparative Example 3: A preparation process for a high-elasticity, wear-resistant EVA shoe sole material, comprising the following processes:

[0070] The preparation method of modified zinc oxide whiskers includes the following steps:

[0071] Step 1: Mix 8 parts of zinc oxide whiskers, 88 parts of anhydrous ethanol, 24 parts of deionized water and 3.2 parts of 3-aminopropyltriethoxysilane, sonicate for 40 min, react at 65℃ for 5 h, and after centrifugation, washing and drying, obtain aminated zinc oxide whiskers.

[0072] Step 2: Mix 8 parts of aminated zinc oxide whiskers, 24 parts of epoxidized EVA and 120 parts of toluene evenly, react at 55°C for 18 hours, introduce nitrogen gas, add 8 parts of isocyanate-terminated polybutadiene and 0.02 parts of dibutyltin dilaurate and mix evenly, react at 75°C for 4 hours, cool to room temperature, filter, wash and dry to obtain modified zinc oxide whiskers;

[0073] Epoxidation of EVA includes the following steps:

[0074] Step A: Mix 24 parts of ethylene-vinyl acetate copolymer, 190 parts of methanol and 360 parts of toluene evenly, add 9 parts of sodium hydroxide, react at 50°C for 4 hours, filter, wash with methanol and vacuum dry to obtain hydroxyl-containing EVA;

[0075] Step B: Mix 24 parts of hydroxyl-containing EVA, 60 parts of epichlorohydrin and 1.5 parts of benzyltriethylammonium chloride evenly, react at 85°C under a nitrogen atmosphere for 4 hours, cool down to 52°C, add 20 parts of 35wt% sodium hydroxide solution, and continue the reaction for 2.5 hours. After filtration, washing and drying, epoxidized EVA is obtained.

[0076] Compared with Example 2, Comparative Example 3 replaced gallic acid-grafted EVA with the same mass of hydroxyl-containing EVA, did not introduce gallic acid, and the other steps were the same as in Example 2.

[0077] Comparative Example 4: A preparation process for a high-elasticity, wear-resistant EVA shoe sole material, comprising the following processes:

[0078] Step 1: Mix 8 parts of zinc oxide whiskers, 88 parts of anhydrous ethanol, 24 parts of deionized water and 3.2 parts of 3-aminopropyltriethoxysilane, sonicate for 40 min, react at 65℃ for 5 h, and after centrifugation, washing and drying, obtain aminated zinc oxide whiskers.

[0079] Step 2: Mix 8 parts of aminated zinc oxide whiskers and 120 parts of toluene evenly, purge with nitrogen, add 8 parts of isocyanate-terminated polybutadiene and 0.02 parts of dibutyltin dilaurate and mix evenly. React at 75°C for 4 hours, cool to room temperature, filter, wash and dry to obtain modified zinc oxide whiskers.

[0080] Compared with Example 2, Comparative Example 4 did not introduce epoxidized EVA, but the other steps were the same as in Example 2.

[0081] Experiment: Samples were prepared from the highly elastic and abrasion-resistant EVA shoe sole materials obtained in Examples 1-3 and Comparative Examples 1-4. The properties of these samples were tested, and the results were recorded.

[0082] Tensile strength was tested according to GB / T6344-2008 standard using an electronic universal testing machine at a test speed of 500 mm / min. Springback was tested using a GT-7042-RE impact elasticity testing machine. Abrasion resistance was tested according to ISO4649 standard using an abrasion tester with a roller diameter of 150 mm, a rotation speed of 40 r / min, and a friction distance of 40 m. The test sample had a diameter of 16 mm and a thickness of 6 mm, and the test load was 10 N. The abrasion amount was measured and calculated.

[0083] The test results are shown in Table 1.

[0084] Table 1. Performance test results of high-elasticity, abrasion-resistant EVA shoe sole material

[0085] Tensile strength / MPa Rebound rate / % <![CDATA[Wear amount / mm 3 > Example 1 23.4 60 56 Example 2 24.5 62 52 Example 3 25.0 63 48 Comparative Example 1 20.4 49 70 Comparative Example 2 21.7 55 63 Comparative Example 3 22.8 58 60 Comparative Example 4 21.2 53 65

[0086] Based on the data in the table above, the following conclusions can be clearly drawn:

[0087] Combining Examples 1-3 and Comparative Examples 1-4, it can be seen that the high-elasticity, wear-resistant EVA sole material prepared by the present invention has good tensile strength, wear resistance, and elasticity, improving comfort while ensuring good strength. The performance of the product prepared using aminated zinc oxide whiskers in Comparative Example 1 decreased, indicating that the modified zinc oxide whiskers prepared by the present invention have better mechanical properties and compatibility, thus effectively improving the overall performance of the material. In Comparative Example 2, the absence of terminal isocyanate-terminated polybutadiene resulted in decreased material resilience. In Comparative Example 3, the absence of gallic acid led to a decrease in crosslinking density, thereby reducing the strength and toughness of the material. In Comparative Example 4, the absence of epoxidized EVA resulted in decreased compatibility of the zinc oxide whiskers, thus affecting the mechanical properties of the material.

[0088] This indicates that the modified carbon black prepared by this invention has better flame retardant effect and compatibility than carbon black, thereby effectively improving the flame retardant performance and mechanical properties of the material; compared with 3-glycidyl etheroxypropyltrimethoxysilane, the macromolecular coupling agent prepared by this invention has better modification effect, thereby improving the compatibility between inorganic fillers and polymer matrix.

[0089] 1. It is explained that the performance of the cleaning agent prepared by the present invention is affected by its component ratio. By selecting the component ratio within the range described above, a cleaning agent with good cleaning effect can be prepared.

[0090] 2. Compared with Examples 1-3, the tensile strength retention rate and elongation at break retention rate of the product obtained in Comparative Example 3 both decreased. This indicates that the radiation-resistant additive prepared in this invention has excellent radiation resistance and compatibility. Compared with boron nitride, this additive can better improve the mechanical properties of materials under radiation environment and is suitable for use in nuclear power plants.

[0091] 3. Compared with Examples 1-3, the tensile strength retention rate and elongation at break retention rate of the product obtained in Comparative Example 4 both decreased. It can be seen that when the amount of carboxylated polyphenylene sulfide added is reduced, the radiation resistance performance of the radiation-resistant additive will decrease.

[0092] 4. It is known that the performance of the modified acrylic polymer prepared by the present invention is affected by the ratio of each reagent in its preparation process. By selecting the mass ratio within the range described above, the prepared modified acrylic polymer has excellent dispersibility, thereby improving the cleaning effect of the detergent.

[0093] 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.

Claims

1. A highly elastic and wear-resistant EVA shoe sole material, characterized in that: The sole material is composed of the following raw materials in parts by weight: 50-60 parts of ethylene-vinyl acetate copolymer, 10-20 parts of ethylene-octene copolymer, 20-30 parts of thermoplastic elastomer, 5-10 parts of modified zinc oxide whiskers, 2-5 parts of talc, 1-3 parts of zinc stearate, 0.5-1.5 parts of stearic acid, 2-5 parts of foaming agent, 1-2 parts of crosslinking agent, and 0.3-0.8 parts of antioxidant.

2. The high-elasticity, wear-resistant EVA sole material according to claim 1, characterized in that: The method for preparing the modified zinc oxide whiskers includes the following steps: Step 1: Mix zinc oxide whiskers, anhydrous ethanol, deionized water and 3-aminopropyltriethoxysilane, sonicate for 30-50 min, react at 60-70℃ for 4-6 h, and after centrifugation, washing and drying, obtain aminated zinc oxide whiskers. Step 2: Mix aminated zinc oxide whiskers, epoxidized EVA and toluene evenly, react at 50-60℃ for 12-24h, introduce nitrogen gas, add isocyanate-terminated polybutadiene and dibutyltin dilaurate and mix evenly, react at 70-80℃ for 3-5h, cool to room temperature, filter, wash and dry to obtain modified zinc oxide whiskers.

3. The high-elasticity, wear-resistant EVA sole material according to claim 2, characterized in that: In step 1, the mass ratio of zinc oxide whiskers to anhydrous ethanol, deionized water, and 3-aminopropyltrimethoxysilane is 1:(10-12):(2-4):(0.3-0.5).

4. The high-elasticity, wear-resistant EVA sole material according to claim 2, characterized in that: In step 2, the mass ratio of aminated zinc oxide whiskers, epoxidized EVA and toluene is 1:(2-4):(10-20).

5. The high-elasticity, wear-resistant EVA sole material according to claim 4, characterized in that: The preparation method of the epoxidized EVA includes the following steps: Step A: Mix ethylene-vinyl acetate copolymer, methanol and toluene evenly, add sodium hydroxide, react at 45-55℃ for 3-5 hours, filter, wash with methanol and vacuum dry to obtain hydroxyl-containing EVA; Step B: Mix hydroxyl-containing EVA, gallic acid and toluene evenly, add p-toluenesulfonic acid, and react under a nitrogen atmosphere at 110-120℃ for 12-14 hours. After precipitation, filtration, washing and vacuum drying, gallic acid-grafted EVA is obtained. Step C: Gallic acid-grafted EVA, epichlorohydrin, and benzyltriethylammonium chloride are mixed evenly and reacted at 80-90℃ under a nitrogen atmosphere for 3-5 hours. The temperature is then lowered to 50-55℃, sodium hydroxide solution is added, and the reaction continues for 2-3 hours. After filtration, washing, and drying, epoxidized EVA is obtained.

6. The high-elasticity, wear-resistant EVA sole material according to claim 5, characterized in that: In step B, the mass ratio of hydroxyl EVA, gallic acid, toluene, and p-toluenesulfonic acid is 1:(0.2-0.4):(10-20):(0.1-0.3).

7. The high-elasticity, wear-resistant EVA sole material according to claim 5, characterized in that: In step C, the mass ratio of gallic acid-grafted EVA, epichlorohydrin, benzyltriethylammonium chloride, and sodium hydroxide solution is 1:(2-3):(0.05-0.08):(0.5-1.0), and the concentration of sodium hydroxide solution is 30-40 wt%.

8. The high-elasticity, wear-resistant EVA sole material according to claim 2, characterized in that: In step 2, the amount of terminal isocyanate-based polybutadiene used is 50-150% of the mass of aminated zinc oxide whiskers.

9. The preparation process of a high-elasticity, wear-resistant EVA shoe sole material according to any one of claims 1-8, characterized in that: Includes the following steps: Ethylene-vinyl acetate copolymer, ethylene-octene copolymer, thermoplastic elastomer, modified zinc oxide whiskers, talc, zinc stearate, stearic acid and antioxidant are mixed and kneaded at 100-120℃ for 20-30 minutes. Then foaming agent and crosslinking agent are added and kneaded for another 10-15 minutes. The mixture is discharged, placed in a mold, and molded by compression molding to obtain a high-elasticity and wear-resistant EVA shoe sole material.

10. The preparation process of a high-elasticity, wear-resistant EVA shoe sole material according to claim 9, characterized in that: The foaming molding temperature is 160-180℃, the pressure is 10-20MPa, and the holding time is 5-10min.