Rubber composite material composition for shoe soles and preparation method of rubber composite material composition

Abstract

The invention discloses a rubber composite material composition for shoe soles and a preparation method of the rubber composite material composition, and relates to the technical field of shoe materials. The composition is prepared from the following components: 6 to 12 parts of artificial rubber TPE, 24 to 30 parts of isoprene rubber, 6 to 9 parts of nitrile rubber, 20 to 35 parts of natural rubber, 4 to 7 parts of ethylene propylene diene monomer EPDM, 5 to 11 parts of polyolefin elastomer POE, 10 to 13 parts of hydrogenated styrene block copolymer, 6 to 15 parts of modified zinc oxide whisker, 0.2 to 0.8 part of foaming agent and 0.3 to 0.6 part of paraffin. The composition provided by the invention has excellent elastic recovery, wear resistance, oil resistance, aging resistance and processing fluidity, the introduction of the modified whiskers not only provides mechanical enhancement and interface compatibility improvement, but also endows the material with lasting thermal oxidation resistance, and significantly improves the comfort and prolongs the service life while ensuring the high strength and durability of the sole.

Description

Technical Field

[0001] This invention relates to the field of footwear materials technology, specifically to a rubber composite material composition for shoe soles and its preparation method. Background Technology

[0002] As consumers' demands for footwear performance continue to rise, the overall performance of sole materials, as key components that directly bear the weight of the human body and the impact of the ground, directly affects the comfort, durability, and safety of footwear products. Modern sole materials need to simultaneously possess multiple requirements, including excellent elastic recovery, abrasion and oil resistance, aging resistance, lightweight, and good processing performance.

[0003] Currently, most shoe sole rubber materials on the market employ a technical approach of using a single or a few types of rubber matrices in combination. Common rubber matrices include natural rubber, nitrile rubber, and EPDM rubber, but a single rubber system often struggles to simultaneously meet multiple performance requirements. For example, natural rubber possesses excellent elasticity and strength, but its weather resistance and oil resistance are relatively poor; nitrile rubber exhibits outstanding oil resistance, but its elastic recovery ability is limited; EPDM rubber has good weather resistance, but its mechanical strength is relatively low. Therefore, achieving synergistic and balanced performance through the scientific formulation of multi-component rubbers remains a significant technical challenge in this field.

[0004] In terms of filler modification, zinc oxide, as an important functional filler in the rubber industry, not only possesses vulcanization activity but also provides a certain reinforcing effect. However, traditional zinc oxide powder suffers from poor dispersibility and weak interfacial bonding in the rubber matrix, easily leading to localized stress concentration and affecting the overall performance of the material. Although zinc oxide whiskers offer superior reinforcing effects compared to powders, their surface polarity and compatibility with the organic rubber matrix remain poor, limiting their application potential.

[0005] In existing technologies, surface modification of zinc oxide fillers mainly employs simple treatment methods such as silane coupling agents, which have limited modification capabilities and fail to fully realize the reinforcing effect of the filler. Meanwhile, traditional anti-aging agents are mostly small molecule compounds, which suffer from problems such as easy migration and volatilization loss, making it difficult to provide long-lasting protective effects.

[0006] Furthermore, as consumers increasingly demand greater comfort in footwear, lightweighting and cushioning have become crucial directions for the development of sole materials. While traditional foaming technology can reduce material density, it often comes at the cost of a significant decrease in mechanical properties. Achieving effective weight reduction while maintaining strength still requires technological breakthroughs.

[0007] Therefore, developing a rubber composite material composition for shoe soles that combines high strength, excellent elasticity, good aging resistance, and lightweight characteristics, and establishing a corresponding efficient preparation process, has significant technical value and market significance. Summary of the Invention

[0008] To address the shortcomings of existing technologies, the present invention aims to provide a rubber composite material composition for shoe soles and its preparation method. The composition of the present invention possesses excellent elastic recovery, abrasion and oil resistance, aging resistance, and processing fluidity. The introduction of modified whiskers not only provides mechanical reinforcement and improved interfacial compatibility but also endows the material with long-lasting resistance to thermal oxidation. This composition significantly improves comfort and service life while ensuring high strength and durability of the shoe sole.

[0009] To achieve the above objectives, the present invention adopts the following technical solution: A rubber composite composition for shoe soles, comprising, by weight, the following components: 6-12 parts of synthetic rubber (TPE), 24-30 parts of isoprene rubber, 6-9 parts of nitrile rubber, 20-35 parts of natural rubber, 4-7 parts of ethylene propylene diene monomer (EPDM), 5-11 parts of polyolefin elastomer (POE), 10-13 parts of hydrogenated styrene block copolymer, 6-15 parts of modified zinc oxide whiskers, 0.2-0.8 parts of foaming agent, and 0.3-0.6 parts of paraffin wax. Preferably, the modified zinc oxide whiskers are prepared by the following method steps: (1) Disperse zinc oxide whiskers in anhydrous ethanol, ultrasonically disperse them evenly, then add a small amount of deionized water, slowly add KH550, stir the reaction, filter, wash and dry the product to obtain pretreated zinc oxide whiskers. Amination of Zinc Oxide Whiskers: The surface of zinc oxide whiskers contains numerous hydroxyl groups (-OH). KH550 silane coupling agent undergoes hydrolysis in the presence of a small amount of water, converting ethoxy groups (-OEt) into silanol groups (-SiOH). Subsequently, the silanol groups undergo dehydration condensation with the hydroxyl groups on the zinc oxide surface, forming Si-O-Zn covalent bonds, while simultaneously introducing aminopropyl chains (-CH2CH2CH2NH2) onto the whisker surface. This step achieves amination modification of the zinc oxide whisker surface, providing active amino functional groups for subsequent reactions.

[0010] Preferably, in step (1), the ratio of zinc oxide whiskers, anhydrous ethanol, deionized water, and KH550 is 10g: 100~150mL: 0.1~0.3mL: 1~4mL.

[0011] Preferably, in step (1), ultrasonic dispersion is performed for 20-40 min, and the stirring reaction is performed at 60-75℃ for 4-7 h.

[0012] (2) Disperse the pretreated zinc oxide whiskers, 2,4-pentadienoic acid and DMAP into DMF, add DCC under ice bath, heat the reaction under nitrogen atmosphere, filter, wash and dry the product to obtain intermediate whiskers; Whisker surface esterification: 2,4-pentadienoic acid is activated by DCC (dicyclohexylcarbodiimide), and the carboxyl group combines with DCC to form an active ester intermediate. Simultaneously, the DMAP catalyst promotes the reaction. The amino groups on the pretreated zinc oxide whisker surface undergo nucleophilic substitution with the active ester to form stable amide bonds (C-NH-CO), and the byproduct dicyclohexylurea is removed by washing. This step successfully links 2,4-pentadienoic acid containing C=C double bonds to the whisker surface, maintaining the reactivity of the double bonds while achieving surface functionalization.

[0013] Preferably, in step (2), the ratio of the amount of pretreated zinc oxide whiskers, 2,4-pentadienoic acid, DMAP, DMF and DCC is 10g: 2~5g: 0.1~0.4g: 100~200mL: 1~3g.

[0014] Preferably, in step (2), the ice bath is 0~5℃; the temperature reaction conditions are to raise the temperature to 60~75℃ and react for 7~10h.

[0015] (3) Disperse the intermediate whiskers into toluene, then add eugenol and BPO, reflux the reaction under a nitrogen atmosphere, cool, filter, wash and dry the product to obtain modified zinc oxide whiskers.

[0016] Addition polymerization on the surface of whiskers: Benzoyl peroxide (BPO) decomposes at reflux temperature to generate free radicals, which initiate a free radical polymerization reaction. The double bonds on the surface of the intermediate whiskers open under the action of free radicals and undergo an addition reaction with the allyl side chain (-CH2CH=CH2) of the eugenol molecule, constructing polymer molecular chains on the whisker surface, and finally forming a polymer coating layer mainly composed of eugenol, thus achieving the organic modification of zinc oxide whiskers.

[0017] Preferably, in step (3), the ratio of intermediate whiskers, toluene, eugenol and BPO is 10g: 150~200mL: 5~8mL: 0.2~0.5g.

[0018] Preferably, in step (3), the reflux reaction conditions are reflux reaction at 110°C for 5~8h.

[0019] Preferably, the hydrogenated styrene block copolymer is a hydrogenated styrene-butadiene block copolymer; the blowing agent is blowing agent H and / or sodium bicarbonate.

[0020] This invention also claims a method for preparing the rubber composite composition for shoe soles, comprising the following steps: a. Add TPE (tissue rubber), isoprene rubber, nitrile rubber, natural rubber, and EPDM (ethylene propylene diene monomer) rubber to a mixer and start mixing until all materials are mixed and dissolved to obtain the first mixture. Preferably, in step a, the mixing temperature of the internal mixer is raised to 80~90℃, and the materials are mixed and dissolved to obtain the first mixture.

[0021] b. Add paraffin to the modified zinc oxide whiskers, mix evenly, and then add it together with polyolefin elastomer POE, hydrogenated styrene block copolymer and other remaining components into a mixer. Mix and knead the mixture with the first mixture again. After mixing evenly, start unloading to obtain the second mixture. Preferably, in step b, the mixing temperature of the internal mixer is raised to 110~120℃, and after the materials are mixed evenly, the material is discharged to obtain the second mixture.

[0022] c. The second mixture is fed to an open mill for at least two passes, then to an air-cooled single-screw granulator for extrusion and pelletizing. The pelletized rubber particles are then sent by a high-speed blower to a cyclone drum and a kneader for complete cooling to obtain the rubber composite composition for shoe soles.

[0023] This invention also protects the application of the rubber composite material composition in shoe soles, comprising the following steps: adding the rubber composite material composition into the hopper of an injection molding machine, gradually heating the injection gun and applying pressure to the injection gun to inject the rubber composite material composition into a shoe sole mold, vulcanizing in the mold, opening the mold after vulcanization, and then shrinking and cooling the molded shoe sole obtained after mold opening using a constant temperature production line to obtain the shoe sole.

[0024] Preferably, the vulcanization temperature is 160~165℃ and the vulcanization time is 180~240s.

[0025] Compared with the prior art, the present invention has the following beneficial effects: 1. This invention provides a rubber composite composition that achieves excellent comprehensive performance through the synergistic combination of multiple rubber matrices. TPE (tissue polyethylene) and isoprene rubber provide excellent elastic recovery and fatigue resistance, ensuring good resilience and comfort of the sole. The addition of nitrile rubber significantly improves the material's abrasion resistance and oil resistance, extending the sole's service life. Natural rubber contributes excellent tensile and tear strength. EPDM (ethylene propylene diene monomer) rubber enhances the material's weather resistance and anti-aging properties. The synergistic effect of POE (polyolefin elastomer) and hydrogenated styrene block copolymer improves the material's processing fluidity and toughness balance. Modified zinc oxide whiskers, as a reinforcing filler, not only improve mechanical strength but also enhance the filler's dispersion in the matrix. The introduction of a foaming agent reduces the material density, giving the sole excellent cushioning and shock absorption properties, while the addition of paraffin wax improves processing performance and provides a certain lubrication effect.

[0026] 2. This invention employs a step-by-step mixing process. First, multiple rubber matrices are thoroughly mixed to ensure compatibility. Then, functional additives are added for a second mixing process, effectively avoiding adverse interactions between components. Staged temperature control ensures that each component is fully mixed at an appropriate temperature without thermal degradation. Subsequent open milling, granulation, and cooling processes further guarantee the uniformity and stability of the material's microstructure.

[0027] 3. This invention provides a modified zinc oxide whisker that achieves multiple functional integrations through a three-step surface functionalization process. First, an aminopropyl chain (-CH2CH2CH2NH2) is introduced as a bridging group, which covalently bonds firmly with the inorganic whisker, significantly improving interfacial bonding strength. Subsequently, the grafting of 2,4-pentadienoic acid segments significantly improves surface compatibility. Its unsaturated bond structure is similar to that of rubber molecular chains, enabling it to participate in the vulcanization process and form chemical cross-linking points, thereby enhancing the bonding strength between the filler and the matrix. The surface-polymerized eugenol molecular layer not only provides excellent interfacial compatibility, but more importantly, its natural phenolic structure endows the material with long-lasting antioxidant capabilities. Compared to traditional small-molecule antioxidants, it has stronger retention and persistence, significantly improving the service life of rubber products. Simultaneously, the modified whisker retains the intrinsic reinforcing properties of inorganic particles, providing mechanical strength enhancement while achieving a synergistic toughening effect with the organic matrix through surface modification. This allows the composite material to maintain high strength while possessing good toughness and processability. Detailed Implementation

[0028] To make the objectives, technical solutions, and advantages of this invention clearer, the invention will be further described in detail below with reference to embodiments. Of course, the specific embodiments described herein are only for explaining the invention and are not intended to limit the invention.

[0029] Unless otherwise specified, all chemical reagents and materials in this invention are purchased from the market or synthesized from raw materials purchased from the market.

[0030] The synthetic rubber TPE is JSR RB820 from Japan; The EPDM rubber used is Dow's EPDM4570P. Polyolefin elastomer POE, grade: ENGAGE 8450, brand: Dow, purchased from Suzhou Shunwangjia International Trade Co., Ltd. The zinc oxide whiskers are tetraneedle-shaped zinc oxide whiskers with a diameter of 0.5~5μm and a length of 10~50μm. The grade is FF-JY510, the brand is Jiayou, and it was purchased from Xuancheng Jingrui New Materials Co., Ltd. The foaming agent H refers to N,N-dinitrospentamethylenetetramine.

[0031] The CAS number for hydrogenated styrene-butadiene block copolymer is 66070-58-4.

[0032] A method for preparing a rubber composite material composition for shoe soles, characterized by comprising the following steps: (1) Disperse 10g of zinc oxide whiskers in 100-150mL of anhydrous ethanol, sonicate for 20-40min, then add 0.1-0.3mL of deionized water, slowly add 1-4mL of KH550, stir and react at 60-75℃ for 4-7h, filter, wash and dry the product to obtain pretreated zinc oxide whiskers; (2) Disperse 10g of pretreated zinc oxide whiskers, 2-5g of 2,4-pentadienoic acid and 0.1-0.4g of DMAP into 100-200mL of DMF, add 1-3g of DCC in an ice bath at 0-5℃, and react at 60-75℃ in a nitrogen atmosphere for 7-10h. Filter, wash and dry the product to obtain intermediate whiskers; (3) Disperse 10g of intermediate whiskers into 150-200mL of toluene, then add 5-8mL of eugenol and 0.2-0.5g of BPO, and reflux at 110℃ under nitrogen atmosphere for 5-8h. Cool, filter, wash and dry the product to obtain modified zinc oxide whiskers. (4) Put 6-12 parts of TPE synthetic rubber, 24-30 parts of isoprene rubber, 6-9 parts of nitrile rubber, 20-35 parts of natural rubber, and 4-7 parts of EPDM into a mixer at 80-90°C to start mixing and mixing until all materials are mixed and dissolved to obtain the first mixture; (5) Add 0.3 to 0.6 parts of paraffin to 6 to 15 parts of modified zinc oxide whiskers, mix evenly, and then add 5 to 11 parts of polyolefin elastomer POE, 10 to 13 parts of hydrogenated styrene-butadiene block copolymer and 0.2 to 0.8 parts of foaming agent into a mixer. Mix the mixture with the first mixture at 110 to 120°C and then mix evenly to obtain the second mixture. (6) The second mixture is fed to an open mill for at least two rounds of milling, and then fed to an air-cooled single-screw granulator for extrusion and pelletizing. The pelletized rubber particles are then fed to a cyclone drum and a kneader for complete cooling by a high-speed blower to obtain the rubber composite composition for shoe soles.

[0033] The application of the rubber composite material composition in a shoe sole includes the following steps: The rubber composite material composition is added into the hopper of an injection molding machine. The rubber composite material composition is injected into the shoe sole mold by gradually heating the injection gun and applying pressure inside the injection gun. The mold is vulcanized at 160~165℃ for 180~240 minutes. After vulcanization, the mold is opened. The molded shoe sole is then shrunk and cooled in a constant temperature production line to obtain the shoe sole.

[0034] The present invention will be further described below through specific embodiments.

[0035] Example 1 A method for preparing a rubber composite material composition for shoe soles, characterized by comprising the following steps: (1) Disperse 10g of zinc oxide whiskers in 120mL of anhydrous ethanol, sonicate for 30min, then add 0.2mL of deionized water, slowly add 4mL of KH550, stir at 75℃ for 4h, filter, wash and dry the product to obtain pretreated zinc oxide whiskers. (2) Disperse 10g of pretreated zinc oxide whiskers, 5g of 2,4-pentadienoic acid and 0.4g of DMAP into 150mL of DMF, add 3g of DCC in an ice bath at 2℃, and react at 75℃ in a nitrogen atmosphere for 7h. Filter, wash and dry the product to obtain intermediate whiskers. (3) Disperse 10g of intermediate whiskers into 200mL of toluene, then add 8mL of eugenol and 0.5g of BPO, and reflux at 110℃ under nitrogen atmosphere for 8h. Cool, filter, wash and dry the product to obtain modified zinc oxide whiskers. (4) Put 1200g of TPE synthetic rubber, 3000g of isoprene rubber, 900g of nitrile rubber, 3500g of natural rubber and 700g of EPDM into a mixer at 85°C and start mixing until all materials are mixed and dissolved to obtain the first mixture. (5) Add 60g of paraffin to 1500g of modified zinc oxide whiskers, mix evenly, and then add 1100g of polyolefin elastomer POE, 1300g of hydrogenated styrene-butadiene block copolymer and 80g of foaming agent H into a mixer. Mix and knead the mixture with the first mixture at 115°C. After mixing evenly, start unloading to obtain the second mixture. (6) The second mixture is fed to an open mill for at least two rounds of milling, and then fed to an air-cooled single-screw granulator for extrusion and pelletizing. The pelletized rubber particles are then fed to a cyclone drum and a kneader for complete cooling by a high-speed blower to obtain the rubber composite composition for shoe soles.

[0036] The application of the rubber composite material composition in a shoe sole includes the following steps: The rubber composite material composition is added into the hopper of the injection molding machine. The rubber composite material composition is injected into the shoe sole mold by gradually heating the injection gun and applying pressure inside the injection gun. The mold is vulcanized at 162°C for 220 seconds. After vulcanization, the mold is opened. The molded shoe sole is then shrunk and cooled on a constant temperature production line to obtain the shoe sole.

[0037] Example 2 A method for preparing a rubber composite material composition for shoe soles, characterized by comprising the following steps: (1) Disperse 10g of zinc oxide whiskers in 120mL of anhydrous ethanol, sonicate for 30min, then add 0.2mL of deionized water, slowly add 3mL of KH550, stir at 70℃ for 5h, filter, wash and dry the product to obtain pretreated zinc oxide whiskers. (2) Disperse 10g of pretreated zinc oxide whiskers, 4g of 2,4-pentadienoic acid and 0.3g of DMAP into 150mL of DMF, add 2g of DCC in an ice bath at 2℃, and react at 70℃ in a nitrogen atmosphere for 8h. Filter, wash and dry the product to obtain intermediate whiskers. (3) Disperse 10g of intermediate whiskers into 180mL of toluene, then add 7mL of eugenol and 0.4g of BPO, and reflux at 110℃ under nitrogen atmosphere for 7h. Cool, filter, wash and dry the product to obtain modified zinc oxide whiskers. (4) Put 1000g of TPE synthetic rubber, 2800g of isoprene rubber, 800g of nitrile rubber, 3000g of natural rubber and 600g of EPDM into a mixer at 85°C and start mixing until all materials are mixed and dissolved to obtain the first mixture. (5) Add 50g of paraffin to 1200g of modified zinc oxide whiskers, mix evenly, and then add 900g of polyolefin elastomer POE, 1200g of hydrogenated styrene-butadiene block copolymer and 60g of foaming agent H into a mixer. Mix and knead the mixture with the first mixture at 115°C. After mixing evenly, start unloading to obtain the second mixture. (6) The second mixture is fed to an open mill for at least two rounds of milling, and then fed to an air-cooled single-screw granulator for extrusion and pelletizing. The pelletized rubber particles are then fed to a cyclone drum and a kneader for complete cooling by a high-speed blower to obtain the rubber composite composition for shoe soles.

[0038] The application of the rubber composite material composition in a shoe sole includes the following steps: The rubber composite material composition is added into the hopper of the injection molding machine. The rubber composite material composition is injected into the shoe sole mold by gradually heating the injection gun and applying pressure inside the injection gun. The mold is vulcanized at 162°C for 220 seconds. After vulcanization, the mold is opened. The molded shoe sole is then shrunk and cooled on a constant temperature production line to obtain the shoe sole.

[0039] Example 3 A method for preparing a rubber composite material composition for shoe soles, characterized by comprising the following steps: (1) Disperse 10g of zinc oxide whiskers in 120mL of anhydrous ethanol, sonicate for 30min, then add 0.2mL of deionized water, slowly add 2mL of KH550, stir at 65℃ for 6h, filter, wash and dry the product to obtain pretreated zinc oxide whiskers. (2) Disperse 10g of pretreated zinc oxide whiskers, 3g of 2,4-pentadienoic acid and 0.2g of DMAP into 150mL of DMF, add 2g of DCC in an ice bath at 2℃, and react at 65℃ in a nitrogen atmosphere for 9h. Filter, wash and dry the product to obtain intermediate whiskers. (3) Disperse 10g of intermediate whiskers into 180mL of toluene, then add 6mL of eugenol and 0.3g of BPO, and reflux at 110℃ under nitrogen atmosphere for 6h. Cool, filter, wash and dry the product to obtain modified zinc oxide whiskers. (4) Put 800g of TPE synthetic rubber, 2600g of isoprene rubber, 700g of nitrile rubber, 2500g of natural rubber and 500g of EPDM into a mixer at 85°C and start mixing until all materials are mixed and dissolved to obtain the first mixture. (5) Add 40g of paraffin to 900g of modified zinc oxide whiskers, mix evenly, and then add 700g of polyolefin elastomer POE, 1100g of hydrogenated styrene-butadiene block copolymer and 40g of foaming agent H into a mixer. Mix and knead the mixture with the first mixture at 115°C. After mixing evenly, start unloading to obtain the second mixture. (6) The second mixture is fed to an open mill for at least two rounds of milling, and then fed to an air-cooled single-screw granulator for extrusion and pelletizing. The pelletized rubber particles are then fed to a cyclone drum and a kneader for complete cooling by a high-speed blower to obtain the rubber composite composition for shoe soles.

[0040] The application of the rubber composite material composition in a shoe sole includes the following steps: The rubber composite material composition is added into the hopper of the injection molding machine. The rubber composite material composition is injected into the shoe sole mold by gradually heating the injection gun and applying pressure inside the injection gun. The mold is vulcanized at 162°C for 220 seconds. After vulcanization, the mold is opened. The molded shoe sole is then shrunk and cooled on a constant temperature production line to obtain the shoe sole.

[0041] Example 4 A method for preparing a rubber composite material composition for shoe soles, characterized by comprising the following steps: (1) Disperse 10g of zinc oxide whiskers in 120mL of anhydrous ethanol, sonicate for 30min, then add 0.2mL of deionized water, slowly add 1mL of KH550, stir at 60℃ for 7h, filter, wash and dry the product to obtain pretreated zinc oxide whiskers. (2) Disperse 10g of pretreated zinc oxide whiskers, 2g of 2,4-pentadienoic acid and 0.1g of DMAP into 150mL of DMF, add 1g of DCC in an ice bath at 2℃, and react at 60℃ in a nitrogen atmosphere for 10h. Filter, wash and dry the product to obtain intermediate whiskers. (3) Disperse 10g of intermediate whiskers into 180mL of toluene, then add 5mL of eugenol and 0.2g of BPO, and reflux at 110℃ under nitrogen atmosphere for 5h. Cool, filter, wash and dry the product to obtain modified zinc oxide whiskers. (4) Put 600g of TPE synthetic rubber, 2400g of isoprene rubber, 600g of nitrile rubber, 2000g of natural rubber and 400g of EPDM into a mixer at 85°C and start mixing until all materials are mixed and dissolved to obtain the first mixture. (5) Add 30g of paraffin to 600g of modified zinc oxide whiskers, mix evenly, and then add 500g of polyolefin elastomer POE, 1000g of hydrogenated styrene-butadiene block copolymer and 20g of foaming agent H into a mixer. Mix and knead the mixture with the first mixture at 115°C. After mixing evenly, start unloading to obtain the second mixture. (6) The second mixture is fed to an open mill for at least two rounds of milling, and then fed to an air-cooled single-screw granulator for extrusion and pelletizing. The pelletized rubber particles are then fed to a cyclone drum and a kneader for complete cooling by a high-speed blower to obtain the rubber composite composition for shoe soles.

[0042] The application of the rubber composite material composition in a shoe sole includes the following steps: The rubber composite material composition is added into the hopper of the injection molding machine. The rubber composite material composition is injected into the shoe sole mold by gradually heating the injection gun and applying pressure inside the injection gun. The mold is vulcanized at 162°C for 220 seconds. After vulcanization, the mold is opened. The molded shoe sole is then shrunk and cooled on a constant temperature production line to obtain the shoe sole.

[0043] Comparative Example 1 A method for preparing a rubber composite material composition for shoe soles, characterized by comprising the following steps: (1) Disperse 10g of zinc oxide whiskers in 120mL of anhydrous ethanol, sonicate for 30min, then add 0.2mL of deionized water, slowly add 4mL of KH550, stir at 75℃ for 4h, filter, wash and dry the product to obtain pretreated zinc oxide whiskers. (2) Disperse 10g of pretreated zinc oxide whiskers, 5g of 2,4-pentadienoic acid and 0.4g of DMAP into 150mL of DMF, add 3g of DCC in an ice bath at 2℃, and react at 75℃ in a nitrogen atmosphere for 7h. Filter, wash and dry the product to obtain intermediate whiskers. (3) Put 1200g of TPE synthetic rubber, 3000g of isoprene rubber, 900g of nitrile rubber, 3500g of natural rubber and 700g of EPDM into a mixer at 85°C and start mixing until all materials are mixed and dissolved to obtain the first mixture. (4) Add 60g of paraffin to 1200g of intermediate whiskers and 300g of eugenol, mix evenly, and then add 1100g of polyolefin elastomer POE, 1300g of hydrogenated styrene-butadiene block copolymer and 80g of foaming agent H into a mixer. Mix and then mix with the first mixture at 115°C. After mixing evenly, start unloading to obtain the second mixture. (5) The second mixture is fed to a two-roll mill for at least two rounds of milling, and then fed to an air-cooled single-screw granulator for extrusion and pelletizing. The pelletized rubber particles are then fed to a cyclone drum and a kneader for complete cooling by a high-speed blower to obtain the rubber composite composition for shoe soles.

[0044] The application of the rubber composite material composition in a shoe sole includes the following steps: The rubber composite material composition is added into the hopper of the injection molding machine. The rubber composite material composition is injected into the shoe sole mold by gradually heating the injection gun and applying pressure inside the injection gun. The mold is vulcanized at 162°C for 220 seconds. After vulcanization, the mold is opened. The molded shoe sole is then shrunk and cooled on a constant temperature production line to obtain the shoe sole.

[0045] Comparative Example 2 A method for preparing a rubber composite material composition for shoe soles, characterized by comprising the following steps: (1) Disperse 10g of zinc oxide whiskers in 120mL of anhydrous ethanol, sonicate for 30min, then add 0.2mL of deionized water, slowly add 4mL of KH550, stir at 75℃ for 4h, filter, wash and dry the product to obtain pretreated zinc oxide whiskers. (2) Put 1200g of TPE synthetic rubber, 3000g of isoprene rubber, 900g of nitrile rubber, 3500g of natural rubber and 700g of EPDM into a mixer at 85°C and start mixing until all materials are mixed and dissolved to obtain the first mixture. (3) Add 60g of paraffin to 1200g of pretreated zinc oxide whiskers and 300g of 2,4-pentadienoic acid, mix evenly, and then add 1100g of polyolefin elastomer POE, 1300g of hydrogenated styrene-butadiene block copolymer and 80g of foaming agent H into a mixer. Mix and then mix with the first mixture at 115°C. After mixing evenly, start unloading to obtain the second mixture. (4) The second mixture is fed to an open mill for at least two rounds of milling, and then fed to an air-cooled single-screw granulator for extrusion and pelletizing. The pelletized rubber particles are then fed to a cyclone drum and a kneader for complete cooling by a high-speed blower to obtain the rubber composite composition for shoe soles.

[0046] The application of the rubber composite material composition in a shoe sole includes the following steps: The rubber composite material composition is added into the hopper of the injection molding machine. The rubber composite material composition is injected into the shoe sole mold by gradually heating the injection gun and applying pressure inside the injection gun. The mold is vulcanized at 162°C for 220 seconds. After vulcanization, the mold is opened. The molded shoe sole is then shrunk and cooled on a constant temperature production line to obtain the shoe sole.

[0047] Performance tests were conducted on the soles prepared in Examples 1-4 and Comparative Examples 1-2. The Shore A hardness was tested according to GB / T 531.1-2008 "Test Methods for Indentation Hardness of Vulcanized Rubber or Thermoplastic Rubber Part 1: Shore Hardness Tester Method (Shore Hardness)"; the rebound rate was tested according to GB / T 1681-2009 "Determination of Resilience of Vulcanized Rubber"; the DIN abrasion was tested using a KJ-3025 DIN abrasion tester according to GB / T 9867-2008 "Determination of Abrasion Resistance of Vulcanized Rubber or Thermoplastic Rubber (Rotating Roller Abrasion Tester Method)"; the tensile properties were tested using an electronic tensile testing machine according to GB / T 528-2009 "Determination of Tensile Stress-Strain Properties of Vulcanized Rubber or Thermoplastic Rubber"; the tear properties were tested according to GB / T 529-2008 "Determination of Tear Strength of Vulcanized Rubber or Thermoplastic Rubber (Pants-Shaped, Right-Angle and Crescent-Shaped Specimens)"; and the results were compared with GB / T Heat aging treatment was performed according to GB / T 16585-1996 "Artificial Climate Aging (Fluorescent UV Lamp) Test Method for Vulcanized Rubber or Thermoplastic Rubber" (3512-2014 "Accelerated Aging and Heat Resistance Test of Vulcanized Rubber in Hot Air"). The treatment was carried out at an aging temperature of 80℃ for 120h. UV aging treatment was carried out according to GB / T 16585-1996 "Artificial Climate Aging (Fluorescent UV Lamp) Test Method for Vulcanized Rubber" (325nm wavelength, 40W power xenon lamp irradiation for 72h). The change rate of tensile strength and tear strength was tested after aging. Specific data are shown in Table 1.

[0048] Table 1. Results of sole performance tests

[0049] The above description is only a preferred embodiment of the present invention, but the scope of protection of the present invention is not limited thereto. Any equivalent substitutions or modifications made by those skilled in the art within the scope of the technology disclosed in the present invention, based on the technical solution and inventive concept of the present invention, should be covered within the scope of protection of the present invention.

Claims

1. A rubber composite material composition for shoe soles, characterized in that, It is made of the following components by weight: 6-12 parts of synthetic rubber (TPE), 24-30 parts of isoprene rubber, 6-9 parts of nitrile rubber, 20-35 parts of natural rubber, 4-7 parts of ethylene propylene diene monomer (EPDM), 5-11 parts of polyolefin elastomer (POE), 10-13 parts of hydrogenated styrene block copolymer, 6-15 parts of modified zinc oxide whiskers, 0.2-0.8 parts of foaming agent, and 0.3-0.6 parts of paraffin wax.

2. The rubber composite material composition for shoe soles according to claim 1, characterized in that, The modified zinc oxide whiskers were prepared by the following steps: (1) Disperse zinc oxide whiskers in anhydrous ethanol, ultrasonically disperse them evenly, then add a small amount of deionized water, slowly add KH550, stir the reaction, filter, wash and dry the product to obtain pretreated zinc oxide whiskers. (2) Disperse the pretreated zinc oxide whiskers, 2,4-pentadienoic acid and DMAP into DMF, add DCC under ice bath, heat the reaction under nitrogen atmosphere, filter, wash and dry the product to obtain intermediate whiskers; (3) Disperse the intermediate whiskers into toluene, then add eugenol and BPO, reflux the reaction under a nitrogen atmosphere, cool, filter, wash and dry the product to obtain modified zinc oxide whiskers.

3. The rubber composite material composition for shoe soles according to claim 2, characterized in that, In step (1), the ratio of zinc oxide whiskers, anhydrous ethanol, deionized water, and KH550 is 10g: 100~150mL: 0.1~0.3mL: 1~4mL.

4. The rubber composite material composition for shoe soles according to claim 2, characterized in that, In step (1), ultrasonic dispersion is performed for 20-40 minutes, and the stirring reaction is carried out at 60-75℃ for 4-7 hours.

5. The rubber composite material composition for shoe soles according to claim 2, characterized in that, In step (2), the ratio of the amount of pretreated zinc oxide whiskers, 2,4-pentadienoic acid, DMAP, DMF and DCC is 10g: 2~5g: 0.1~0.4g: 100~200mL: 1~3g.

6. The rubber composite material composition for shoe soles according to claim 2, characterized in that, In step (2), the ice bath is 0~5℃; the temperature reaction conditions are to raise the temperature to 60~75℃ and react for 7~10h.

7. The rubber composite material composition for shoe soles according to claim 2, characterized in that, In step (3), the ratio of intermediate whiskers, toluene, eugenol and BPO is 10g: 150~200mL: 5~8mL: 0.2~0.5g.

8. The rubber composite composition for shoe soles according to claim 2, characterized in that, In step (3), the reflux reaction conditions are reflux reaction at 110℃ for 5~8h.

9. The rubber composite material composition for shoe soles according to claim 1, characterized in that, The hydrogenated styrene block copolymer is a hydrogenated styrene-butadiene block copolymer; the blowing agent is blowing agent H and / or sodium bicarbonate.

10. A method for preparing a rubber composite material composition for shoe soles as described in any one of claims 1 to 9, characterized in that, Includes the following steps: a. Add TPE (tissue rubber), isoprene rubber, nitrile rubber, natural rubber, and EPDM (ethylene propylene diene monomer) rubber to a mixer and start mixing until all materials are mixed and dissolved to obtain the first mixture. b. Add paraffin to the modified zinc oxide whiskers, mix evenly, and then add it together with polyolefin elastomer POE, hydrogenated styrene block copolymer and other remaining components into a mixer. Mix and knead the mixture with the first mixture again. After mixing evenly, start unloading to obtain the second mixture. c. The second mixture is fed to an open mill for at least two passes, then to an air-cooled single-screw granulator for extrusion and pelletizing. The pelletized rubber particles are then sent by a high-speed blower to a cyclone drum and a kneader for complete cooling to obtain the rubber composite composition for shoe soles.

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