Super wear-resistant and non-slip rubber sole material and preparation method thereof

Abstract

The invention relates to the technical field of rubber sole materials and discloses a super wear-resistant and anti-skid rubber sole material and a preparation method thereof. The molecular structure of silicon-containing cardanol grafted polyisoprene rubber is similar to that of natural rubber, and a co-crosslinking reaction occurs between the two. The sulfur-containing groups in the structure can promote vulcanization, thereby increasing the crosslinking density of the rubber. The phenolic hydroxyl groups in the structure can generate hydrogen bonds with hydroxyl groups on the surface of silica, fixing the silica in a matrix like a gripper, improving the dispersibility of silica in the rubber matrix, and increasing the wear resistance of the rubber material. The main chain in the structure of the silicon-containing cardanol grafted polyisoprene rubber is a silicon-oxygen bond, which has a high bond energy and is not easy to break, and has relatively stable chemical properties. The side chains have a flexible long-chain structure and can form a tangled and cross-linked network structure with the rubber matrix, thereby increasing the mechanical properties of the rubber sole material.

Description

Technical Field

[0001] The invention relates to the technical field of rubber sole materials, in particular to a super wear-resistant and anti-skid rubber sole material and a preparation method thereof. Background Art

[0002] Sole materials are a by-product of footwear products. With the development of footwear products, the quality requirements of sole materials are getting higher and higher. Nowadays, most sole materials are made of rubber. For shoe rubber, good wear resistance and anti-slip performance are one of the basic functions that sole rubber products should have. It is also an important indicator to measure the quality of footwear. The wear resistance and anti-slip performance of the sole refers to the anti-slip effect or grip of the sole on the ground. If the anti-slip performance of the sole is not good, it is easy to slip and fall when walking on wet, icy roads. With the prosperous development of the economy and the continuous progress of society, people are making roads and indoor floors smoother and smoother, which makes it more likely to cause falls. Therefore, it is very important to improve the wear resistance and anti-slip performance of the sole material.

[0003] Natural rubber has excellent softness, elasticity and outstanding processability, can be applied to various sports, plays a role in shock absorption, and is widely used in sole materials. However, the wear resistance of natural rubber sole materials is insufficient, and the anti-skid performance needs to be improved. In the prior art, fillers such as white carbon black and nano-silica are generally added as reinforcing materials. However, inorganic reinforcing materials are prone to large-scale agglomeration in the rubber matrix, resulting in stress concentration and cracks in the rubber, and ultimately affecting its wear resistance and anti-skid performance. Invention patent CN106832470B discloses an anti-skid rubber sole and a preparation method thereof. The anti-skid rubber sole is obtained by vulcanization molding of components such as NBR / PVC emulsion co-precipitated alloy, low-melting point polyamide, natural rubber, solution-polymerized styrene-butadiene rubber, brominated butyl rubber, and white carbon black in a space aluminum mold. The obtained anti-skid rubber sole has excellent anti-skid performance, but many components are added and the wear resistance of the sole material is not significantly improved.

[0004] Invention patent CN106589499B discloses an oil-resistant rubber sole for safety shoes and a preparation method thereof. Through pattern design, material selection, and adjustment of the material component ratios, an optimal balance between sole pattern, hardness, and oil-resistant performance is achieved. However, it uses high-vinyl solution-polymerized styrene-butadiene rubber, which is not mass-produced. While the sample performance is excellent, it is expensive, making industrial production difficult. The present invention aims to achieve the dual effects of plasticization and compatibilization by adding silica as a reinforcing agent to natural rubber. The phenolic hydroxyl groups in the structure of the prepared silicon-containing cardanol-grafted polyisoprene rubber form hydrogen bonds with the surface hydroxyl groups of silica, thereby achieving good compatibility with natural rubber, improving the wear resistance of the sole material, and further enhancing the mechanical properties of the material. Summary of the Invention

[0005] In view of this, the object of the present invention is to provide a super wear-resistant and non-slip rubber sole material and a preparation method thereof, so as to solve the problem of poor wear resistance of existing rubber soles.

[0006] In order to achieve the above-mentioned object of the invention, the present invention provides the following technical solutions:

[0007] A super-wear-resistant and anti-skid rubber sole material comprises the following components in parts by weight: 100 parts of natural rubber, 20-35 parts of epoxidized natural rubber, 10-20 parts of white carbon black, 2-10 parts of silicon-containing cardanol grafted polyisoprene rubber, 1-3 parts of stearic acid, 2-4 parts of zinc oxide, 1-2 parts of an accelerator, 3-5 parts of sulfur, and 0.5-1 part of an antioxidant.

[0008] The preparation method of silicon-containing cardanol grafted polyisoprene rubber is as follows: under a nitrogen atmosphere, liquid polyisoprene rubber and silicone-modified cardanol are added to a reaction flask, reacting at 70-90° C. for 20-40 minutes, adding an initiator azobisisobutyronitrile, continuing the reaction for 1-3 hours, performing Soxhlet extraction, and obtaining silicon-containing cardanol grafted polyisoprene rubber after drying.

[0009] Furthermore, the mass amounts of organosilicon-modified cardanol and azobisisobutyronitrile are 6-10% and 0.2-0.5% of the mass amount of the liquid polyisoprene rubber, respectively.

[0010] Furthermore, the preparation method of organosilicon-modified cardanol is as follows:

[0011] Step (1), under a nitrogen atmosphere, add dimethylvinylchlorosilane and ethanol to a reaction flask, stir evenly, add 4-methoxythiophenol and triethylamine, stir and react, after the reaction is completed, extract with ethyl acetate and deionized water, purify the organic phase by column chromatography, and dry to obtain a 4-methoxyphenylchlorosilane intermediate.

[0012] Step (2): under a nitrogen atmosphere, add cardanol and 1,4-dioxane to a reaction flask, stir evenly, add 4-methoxyphenylchlorosilane intermediate and sodium hydride, stir and react, after which the reaction is completed, recrystallize from acetone, filter and wash to obtain 4-methoxyphenylsilane-modified cardanol.

[0013] Step (3): Add 4-methoxyphenylsilane-modified cardanol and dichloromethane to a reaction flask under a nitrogen atmosphere, mix well, add boron tribromide, react at 0-20°C for 8-16 hours, concentrate under reduced pressure, and dry to obtain organosilicon-modified cardanol. The preparation reaction formula is as follows:

[0014]

[0015] Furthermore, in step (1), the molar amounts of 4-methoxythiophenol and triethylamine are 102-110% and 150-200% of the molar amount of dimethylvinylchlorosilane, respectively.

[0016] Furthermore, in step (1), the reaction temperature is 35-50° C., and the reaction time is 12-24 h.

[0017] Furthermore, in step (2), the molar amounts of the 4-methoxyphenylchlorosilane intermediate and sodium hydride are 110-130% and 120-150% of the molar amount of cardanol, respectively.

[0018] Furthermore, in step (2), the reaction temperature is 60-80° C., and the reaction time is 5-12 h.

[0019] Furthermore, in step (3), the molar amount of boron tribromide is 150-220% of the molar amount of 4-methoxyphenylsilane-modified cardanol.

[0020] Furthermore, the preparation method is as follows: natural rubber is added to an open mill and mixed over a roller, epoxidized natural rubber, white carbon black, silicon-containing cardanol grafted polyisoprene rubber, stearic acid, and zinc oxide are added for mixing at a mixing temperature of 50-70°C, and then an accelerator, sulfur, and an antioxidant are added, the mixture is mixed and left to stand for 5-12 hours, and then vulcanized in a flat vulcanizer to obtain an ultra-wear-resistant and anti-slip rubber sole material.

[0021] Furthermore, the vulcanization temperature is 115-130° C., the vulcanization pressure is 20-30 MPa, and the vulcanization time is 5-10 min.

[0022] Compared with the prior art, the present invention has the following beneficial effects:

[0023] The present invention firstly subjects dimethylvinylchlorosilane and 4-methoxythiophenol to a Michael addition reaction under the action of triethylamine to obtain a 4-methoxyphenylchlorosilane intermediate, which is then subjected to a substitution reaction with cardanol to obtain 4-methoxyphenylsilane-modified cardanol. Subsequently, the methoxy group is removed under the action of boron tribromide to obtain organosilicon-modified cardanol. Subsequently, the double bonds on the long chain of cardanol are used to graft with liquid polyisoprene rubber to obtain silicon-containing cardanol-grafted polyisoprene rubber. Finally, the rubber is mixed with natural rubber, white carbon black, etc. and vulcanized to obtain an ultra-wear-resistant and anti-slip rubber sole material.

[0024] The main structure of natural rubber is "cis-1,4-polyisoprene", and the molecular structure of silicon-containing cardanol grafted polyisoprene rubber also contains a large number of similar structures. They are similar and compatible, and a co-cross-linking reaction will occur between the two. The sulfur-containing groups in its structure can promote vulcanization, thereby increasing the cross-linking density of the rubber. At the same time, silica has high fluidity and small size effect, forming a denser structure in the material, thereby reducing the friction coefficient of the material surface, so that the material can reduce wear during movement or use. The phenolic hydroxyl groups in its structure can produce hydrogen bonds with the hydroxyl groups on the surface of silica, fixing silica in the matrix like a gripper, improving the dispersion of silica in the rubber matrix, and increasing the wear resistance of the rubber material.

[0025] The main chain of the silicon-containing cardanol grafted polyisoprene rubber structure is a silicon-oxygen bond, which has a high bond energy and is not easy to break. It has relatively stable chemical properties, a low friction coefficient, and good adhesion, which can effectively increase the adhesion and wear resistance of the rubber material. At the same time, its side chain has a flexible long-chain structure and can form a tangled and cross-linked network structure with the rubber matrix, thereby increasing the mechanical properties of the rubber sole material. The sole material prepared by the present invention has strong dimensional stability, good compatibility between raw materials, good dispersion of fillers in the substrate, and a simple preparation process, which is conducive to industrial production. DETAILED DESCRIPTION

[0026] The following will be combined with the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the embodiments described are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without making any creative efforts shall fall within the scope of protection of the present invention.

[0027] Cardanol: Supplied by Cardolite (Zhuhai, China), light yellow liquid, composed of 41% triene, 36% diene, and 23% monoene, with the structural formula

[0028] Dimethylvinylchlorosilane, CAS number is 1719-58-0.

[0029] 4-Methoxythiophenol, CAS number is 696-63-9.

[0030] Liquid polyisoprene rubber, model YH-LIR-30K, was provided by Shenzhen Masini Elastomer Co., Ltd.

[0031] Example 1

[0032] (1) Under nitrogen atmosphere, 45 mmol of dimethylvinylchlorosilane and 350 mL of ethanol were added to a reaction flask. After stirring, 48.6 mmol of 4-methoxybenzenethiol and 72 mmol of triethylamine were added. The mixture was reacted at 45°C for 16 h. The mixture was extracted with ethyl acetate and deionized water. The organic phase was purified by column chromatography and dried to obtain the 4-methoxyphenylchlorosilane intermediate.

[0033] (2) Under nitrogen atmosphere, 40 mmol of cardanol and 660 mL of 1,4-dioxane were added to the reaction flask. After stirring evenly, 50 mmol of 4-methoxyphenylchlorosilane intermediate and 54 mmol of sodium hydride were added. The mixture was reacted at 70 °C for 10 h, recrystallized from acetone, and filtered and washed to obtain 4-methoxyphenylsilane-modified cardanol.

[0034] (3) Under nitrogen atmosphere, 35 mmol of 4-methoxyphenylsilane-modified cardanol and 1120 mL of dichloromethane were added to a reaction flask. After mixing evenly, 70 mmol of boron tribromide was added. The mixture was reacted at 10°C for 12 h, concentrated under reduced pressure, and dried to obtain organosilicon-modified cardanol.

[0035] (4) Under nitrogen atmosphere, 100 g of liquid polyisoprene rubber and 6 g of organosilicon-modified cardanol were added to a reaction flask and reacted at 80°C for 30 min. 0.3 g of initiator azobisisobutyronitrile was added and the reaction was continued for 2 h. The mixture was subjected to Soxhlet extraction and dried to obtain silicon-containing cardanol-grafted polyisoprene rubber.

[0036] (5) 100 g of natural rubber was added to an open mill and mixed over a roller. 25 g of epoxidized natural rubber, 15 g of white carbon black, 2 g of silicon-containing cardanol grafted polyisoprene rubber, 2 g of stearic acid, and 3 g of zinc oxide were added and mixed at a mixing temperature of 60 ° C. Then, 1.5 g of accelerator DM, 3.5 g of sulfur, and 0.8 g of antioxidant RD were added. The mixture was mixed and placed on a sheet for 8 h. The mixture was then vulcanized on a flat vulcanizer at a vulcanization temperature of 120 ° C, a vulcanization pressure of 25 MPa, and a vulcanization time of 8 min to obtain an ultra-wear-resistant and anti-skid rubber sole material.

[0037] Example 2

[0038] (1) Under nitrogen atmosphere, 80 mmol of dimethylvinylchlorosilane and 400 mL of ethanol were added to a reaction flask. After stirring, 81.6 mmol of 4-methoxythiophenol and 120 mmol of triethylamine were added. The mixture was reacted at 50°C for 12 h. The mixture was extracted with ethyl acetate and deionized water. The organic phase was purified by column chromatography and dried to obtain the intermediate 4-methoxyphenylchlorosilane.

[0039] (2) Under nitrogen atmosphere, 75 mmol of cardanol and 750 mL of 1,4-dioxane were added to the reaction flask. After stirring evenly, 82.5 mmol of 4-methoxyphenylchlorosilane intermediate and 90 mmol of sodium hydride were added. The mixture was reacted at 80 °C for 5 h, recrystallized from acetone, and filtered and washed to obtain 4-methoxyphenylsilane-modified cardanol.

[0040] (3) Under nitrogen atmosphere, 70 mmol of 4-methoxyphenylsilane-modified cardanol and 1750 mL of dichloromethane were added to a reaction flask. After mixing evenly, 105 mmol of boron tribromide was added. The mixture was reacted at 20°C for 8 h, concentrated under reduced pressure, and dried to obtain organosilicon-modified cardanol.

[0041] (4) Under nitrogen atmosphere, 100 g of liquid polyisoprene rubber and 7 g of organosilicon-modified cardanol were added to a reaction flask and reacted at 90°C for 20 min. 0.2 g of initiator azobisisobutyronitrile was added and the reaction was continued for 1 h. The mixture was subjected to Soxhlet extraction and dried to obtain silicon-containing cardanol-grafted polyisoprene rubber.

[0042] (5) 100g of natural rubber was added to an open mill and mixed over a roller. 20g of epoxidized natural rubber, 10g of white carbon black, 4g of silicon-containing cardanol grafted polyisoprene rubber, 3g of stearic acid, and 2g of zinc oxide were added and mixed at a mixing temperature of 70°C. Then, 1g of accelerator DM, 3g of sulfur, and 0.5g of antioxidant RD were added. The mixture was mixed and allowed to stand for 5h. The mixture was then vulcanized on a flat vulcanizer at a vulcanization temperature of 130°C, a vulcanization pressure of 30MPa, and a vulcanization time of 5min to obtain an ultra-wear-resistant and anti-skid rubber sole material.

[0043] Example 3

[0044] (1) Under nitrogen atmosphere, 35 mmol of dimethylvinylchlorosilane and 350 mL of ethanol were added to a reaction flask. After stirring, 38.5 mmol of 4-methoxybenzenethiol and 70 mmol of triethylamine were added. The mixture was reacted at 35°C for 24 h. The mixture was extracted with ethyl acetate and deionized water. The organic phase was purified by column chromatography and dried to obtain the 4-methoxyphenylchlorosilane intermediate.

[0045] (2) Under nitrogen atmosphere, 30 mmol of cardanol and 450 mL of 1,4-dioxane were added to the reaction flask. After stirring evenly, 39 mmol of 4-methoxyphenylchlorosilane intermediate and 45 mmol of sodium hydride were added. The mixture was reacted at 60 °C for 12 h, recrystallized from acetone, and filtered and washed to obtain 4-methoxyphenylsilane-modified cardanol.

[0046] (3) Under nitrogen atmosphere, 25 mmol of 4-methoxyphenylsilane-modified cardanol and 1000 mL of dichloromethane were added to a reaction flask. After mixing evenly, 62.5 mmol of boron tribromide was added. The mixture was reacted at 0°C for 16 h, concentrated under reduced pressure, and dried to obtain organosilicon-modified cardanol.

[0047] (4) Under nitrogen atmosphere, 100 g of liquid polyisoprene rubber and 8 g of organosilicon-modified cardanol were added to a reaction flask and reacted at 70°C for 40 min. 0.5 g of initiator azobisisobutyronitrile was added and the reaction was continued for 3 h. The product was subjected to Soxhlet extraction and dried to obtain silicon-containing cardanol-grafted polyisoprene rubber.

[0048] (5) 100 g of natural rubber was added to an open mill and mixed over a roller. 35 g of epoxidized natural rubber, 20 g of white carbon black, 6 g of silicon-containing cardanol grafted polyisoprene rubber, 3 g of stearic acid, and 4 g of zinc oxide were added and mixed at a mixing temperature of 70 ° C. Then, 2 g of accelerator DM, 5 g of sulfur, and 1 g of antioxidant RD were added. The mixture was mixed and placed on a sheet for 12 h. The mixture was then vulcanized on a flat vulcanizer at a vulcanization temperature of 115 ° C, a vulcanization pressure of 20 MPa, and a vulcanization time of 10 min to obtain an ultra-wear-resistant and anti-skid rubber sole material.

[0049] Example 4

[0050] (1) Under nitrogen atmosphere, 50 mmol of dimethylvinylchlorosilane and 300 mL of ethanol were added to a reaction flask. After stirring, 52.5 mmol of 4-methoxythiophenol and 82.5 mmol of triethylamine were added. The mixture was reacted at 40°C for 16 h. The mixture was extracted with ethyl acetate and deionized water. The organic phase was purified by column chromatography and dried to obtain the intermediate 4-methoxyphenylchlorosilane.

[0051] (2) Under nitrogen atmosphere, 40 mmol of cardanol and 52 mL of 1,4-dioxane were added to the reaction flask. After stirring evenly, 50 mmol of 4-methoxyphenylchlorosilane intermediate and 52.8 mmol of sodium hydride were added. The mixture was reacted at 75 °C for 9 h, recrystallized from acetone, and filtered and washed to obtain 4-methoxyphenylsilane-modified cardanol.

[0052] (3) Under nitrogen atmosphere, 30 mmol of 4-methoxyphenylsilane-modified cardanol and 1000 mL of dichloromethane were added to a reaction flask. After mixing evenly, 55.5 mmol of boron tribromide was added. The mixture was reacted at 5°C for 15 h, concentrated under reduced pressure, and dried to obtain organosilicon-modified cardanol.

[0053] (4) Under nitrogen atmosphere, 100 g of liquid polyisoprene rubber and 9 g of organosilicon-modified cardanol were added to a reaction flask and reacted at 85°C for 35 min. 0.3 g of initiator azobisisobutyronitrile was added and the reaction was continued for 2 h. The product was subjected to Soxhlet extraction and dried to obtain silicon-containing cardanol-grafted polyisoprene rubber.

[0054] (5) 100 g of natural rubber was added to an open mill and mixed over a roller. 30 g of epoxidized natural rubber, 12 g of white carbon black, 8 g of silicon-containing cardanol grafted polyisoprene rubber, 2 g of stearic acid, and 3 g of zinc oxide were added and mixed at a mixing temperature of 65 ° C. Then, 2 g of accelerator DM, 4 g of sulfur, and 0.8 g of antioxidant RD were added. The mixture was mixed and placed on a sheet for 10 h. The mixture was then vulcanized on a flat vulcanizer at a vulcanization temperature of 120 ° C, a vulcanization pressure of 24 MPa, and a vulcanization time of 6 min to obtain an ultra-wear-resistant and anti-skid rubber sole material.

[0055] Example 5

[0056] (1) Under nitrogen atmosphere, 25 mmol of dimethylvinylchlorosilane and 150 mL of ethanol were added to a reaction flask. After stirring, 26.5 mmol of 4-methoxybenzenethiol and 40 mmol of triethylamine were added. The mixture was reacted at 45°C for 24 h. The mixture was extracted with ethyl acetate and deionized water. The organic phase was purified by column chromatography and dried to obtain the intermediate 4-methoxyphenylchlorosilane.

[0057] (2) Under nitrogen atmosphere, 20 mmol of cardanol and 260 mL of 1,4-dioxane were added to the reaction flask, stirred evenly, and then 23 mmol of 4-methoxyphenylchlorosilane intermediate and 27 mmol of sodium hydride were added. The mixture was reacted at 70 °C for 12 h, recrystallized from acetone, and filtered and washed to obtain 4-methoxyphenylsilane-modified cardanol.

[0058] (3) Under nitrogen atmosphere, 15 mmol of 4-methoxyphenylsilane-modified cardanol and 525 mL of dichloromethane were added to a reaction flask. After mixing evenly, 27 mmol of boron tribromide was added. The mixture was reacted at 0°C for 16 h, concentrated under reduced pressure, and dried to obtain organosilicon-modified cardanol.

[0059] (4) Under nitrogen atmosphere, 100 g of liquid polyisoprene rubber and 10 g of organosilicon-modified cardanol were added to a reaction flask and reacted at 90°C for 30 min. 0.4 g of initiator azobisisobutyronitrile was added and the reaction was continued for 3 h. The mixture was subjected to Soxhlet extraction and dried to obtain silicon-containing cardanol-grafted polyisoprene rubber.

[0060] (5) 100 g of natural rubber was added to an open mill and mixed over a roller. 30 g of epoxidized natural rubber, 12 g of white carbon black, 10 g of silicon-containing cardanol grafted polyisoprene rubber, 2 g of stearic acid, and 3 g of zinc oxide were added and mixed at a mixing temperature of 60 ° C. Then, 2 g of accelerator DM, 5 g of sulfur, and 0.5 g of antioxidant RD were added. The mixture was mixed and placed on a sheet for 10 h. The mixture was then vulcanized on a flat vulcanizer at a vulcanization temperature of 125 ° C, a vulcanization pressure of 22 MPa, and a vulcanization time of 10 min to obtain an ultra-wear-resistant and anti-skid rubber sole material.

[0061] Comparative Example 1

[0062] (1) Under a nitrogen atmosphere, 100 g of liquid polyisoprene rubber and 6 g of 4-methoxyphenylsilane-modified cardanol (prepared in Example 1) were added to a reaction flask, and the mixture was reacted at 80° C. for 30 min. 0.3 g of azobisisobutyronitrile (initiator) was added, and the reaction was continued for 2 h. Soxhlet extraction was performed, and the mixture was dried to obtain 4-methoxyphenylsilane-cardanol-grafted polyisoprene rubber.

[0063] (2) 100 g of natural rubber was added to an open mill and mixed over a roller. 25 g of epoxidized natural rubber, 15 g of white carbon black, 2 g of 4-methoxyphenylsilane cardanol grafted polyisoprene rubber, 2 g of stearic acid, and 3 g of zinc oxide were added and mixed at a mixing temperature of 60 ° C. Then, 1.5 g of accelerator DM, 3.5 g of sulfur, and 0.8 g of antioxidant RD were added. The mixture was mixed and placed on a sheet for 8 h. The mixture was then vulcanized on a flat vulcanizer at a vulcanization temperature of 120 ° C, a vulcanization pressure of 25 MPa, and a vulcanization time of 8 min to obtain a rubber sole material.

[0064] Comparative Example 2

[0065] (1) Under nitrogen atmosphere, 100 g of liquid polyisoprene rubber and 6 g of cardanol were added to a reaction flask and reacted at 80°C for 30 min. 0.3 g of azobisisobutyronitrile (ABI) was added and the reaction was continued for 2 h. The mixture was subjected to Soxhlet extraction and dried to obtain cardanol-grafted polyisoprene rubber.

[0066] (2) 100 g of natural rubber was added to an open mill and mixed over a roller. 25 g of epoxidized natural rubber, 15 g of white carbon black, 2 g of cardanol grafted polyisoprene rubber, 2 g of stearic acid, and 3 g of zinc oxide were added and mixed at a mixing temperature of 60 ° C. Then, 1.5 g of accelerator DM, 3.5 g of sulfur, and 0.8 g of antioxidant RD were added. The mixture was mixed and placed on a plate vulcanizer for 8 h. The mixture was then vulcanized at a vulcanization temperature of 120 ° C, a vulcanization pressure of 25 MPa, and a vulcanization time of 8 min to obtain a rubber sole material.

[0067] Comparative Example 3

[0068] 100g of natural rubber was added to an open mill and mixed over a roller. 25g of epoxidized natural rubber, 15g of white carbon black, 2g of stearic acid, and 3g of zinc oxide were added and mixed at a mixing temperature of 60°C. Subsequently, 1.5g of accelerator DM, 3.5g of sulfur, and 0.8g of antioxidant RD were added. The mixture was mixed and the sheet was left to stand for 8h. The sheet was then vulcanized on a flat vulcanizer at a vulcanization temperature of 120°C, a vulcanization pressure of 25MPa, and a vulcanization time of 8min to obtain a rubber sole material.

[0069] DIN abrasion performance test: The test was conducted in accordance with GB 9867-2008 using a DIN abrasion tester. The prepared rubber sole material was made into a cylindrical shape with a diameter of 16 mm and a height of 8 mm. The test wear stroke was 40 mm (equivalent to 84 r), and the average value was taken after 5 measurements.

[0070] Table 1 Wear resistance test

[0071]

[0072]

[0073] From the test results in the table above, it can be seen that with the increase of the content of silicon-containing cardanol grafted polyisoprene rubber, the DIN wear volume of the rubber sole material gradually decreases, among which the wear volume in Example 5 is only 85.5 mm 3 This is because, on the one hand, the double bonds in the long chain of cardanol can form bonds with the double bonds of polyisoprene rubber, thereby improving the compatibility with the matrix rubber. The sulfur-containing groups in its structure can promote vulcanization, thereby increasing the cross-linking density of the rubber. At the same time, silica has high fluidity and small size effect, forming a denser structure in the material, thereby reducing the friction coefficient of the material surface, so that the material can reduce wear during movement or use. The phenolic hydroxyl groups in its structure can produce hydrogen bonds with the hydroxyl groups on the surface of silica, fixing silica in the matrix like a gripper, improving the dispersion of silica in the rubber matrix, and increasing the wear resistance of the rubber material. On the other hand, the main chain in the structure of silicon-containing cardanol grafted polyisoprene rubber is a silicon-oxygen bond, which has a high bond energy and is not easy to break, is chemically stable, has a small friction coefficient, and has good adhesion, which can effectively increase the adhesion and wear resistance of the rubber material.

[0074] Comparative Example 1 does not contain phenolic hydroxyl groups and cannot produce hydrogen bonds with silica, resulting in poor dispersibility and affected wear resistance. Comparative Example 2 does not contain an organosiloxane structure and has a larger DIN wear volume. Comparative Example 3 does not contain long chains of organosilicon and cardanol and has the worst wear resistance.

[0075] Anti-slip performance test: Refer to STM603 of British SATRA company and TM144 standard, use anti-slip tester to test dry and wet anti-slip coefficients in smooth state.

[0076] Table 2 Anti-slip performance test

[0077]

[0078]

[0079] The anti-slip coefficient, also known as the coefficient of friction, is a measure of surface friction. In specific situations, such as friction between a shoe sole and the ground, the anti-slip coefficient directly affects the shoe's grip and anti-slip performance. Generally speaking, a larger anti-slip coefficient indicates greater friction between objects, meaning better grip on the surface, providing greater stability and safety. The test results in the table above show that the anti-slip coefficient of the rubber sole material gradually increases with increasing content of silicon-containing cardanol-grafted polyisoprene rubber. This is because the primary structure of natural rubber is "cis-1,4-polyisoprene," and the molecular structure of silicon-containing cardanol-grafted polyisoprene rubber also contains a large number of similar structures. These structures are similar and compatible, resulting in a co-crosslinking reaction between the two and hydrogen bonding with silica, increasing the anti-slip coefficient and enhancing anti-slip performance.

[0080] Mechanical properties test: An electronic tensile testing machine was used to test the tensile properties and tearing properties in accordance with GB / T 528-2009 and GB / T529-2008 respectively.

[0081] Table 3 Mechanical properties test

[0082]

[0083]

[0084] Although the embodiments of the present invention have been disclosed above, they are not limited to the applications listed in the description and implementation methods. They can be fully applied to various fields suitable for the present invention. For those familiar with the art, additional modifications can be easily implemented. Therefore, without departing from the general concept defined by the claims and the scope of equivalents, the present invention is not limited to the specific details and embodiments shown and described herein.

Claims

1. A super wear-resistant and non-slip rubber sole material, characterized in that: The rubber sole material comprises the following components in parts by weight: 100 parts of natural rubber, 20-35 parts of epoxidized natural rubber, 10-20 parts of white carbon black and 2-10 parts of silicon-containing cardanol grafted polyisoprene rubber, 1-3 parts of stearic acid, 2-4 parts of zinc oxide, 1-2 parts of accelerator, 3-5 parts of sulfur and 0.5-1 part of antioxidant; The preparation method of the silicon-containing cardanol grafted polyisoprene rubber comprises: adding liquid polyisoprene rubber and organosilicon-modified cardanol to a reaction flask under a nitrogen atmosphere, reacting at 70-90° C. for 20-40 minutes, adding an initiator azobisisobutyronitrile, continuing the reaction for 1-3 hours, performing Soxhlet extraction, and drying to obtain the silicon-containing cardanol grafted polyisoprene rubber; The preparation method of the organosilicon-modified cardanol is as follows: Step (1), under a nitrogen atmosphere, add dimethylvinylchlorosilane and ethanol to a reaction flask, stir evenly, add 4-methoxythiophenol and triethylamine, stir and react, after the reaction is completed, extract with ethyl acetate and deionized water, purify the organic phase by column chromatography, and dry to obtain a 4-methoxyphenylchlorosilane intermediate; Step (2), under a nitrogen atmosphere, add cardanol and 1,4-dioxane to a reaction flask, stir evenly, add 4-methoxyphenylchlorosilane intermediate and sodium hydride, stir and react, after the reaction is completed, recrystallize with acetone, filter and wash to obtain 4-methoxyphenylsilane-modified cardanol; Step (3): Add 4-methoxyphenylsilane-modified cardanol and dichloromethane to a reaction flask under a nitrogen atmosphere, mix well, add boron tribromide, react at 0-20°C for 8-16h, concentrate under reduced pressure, and dry to obtain organosilicon-modified cardanol.

2. The super wear-resistant and non-slip rubber sole material according to claim 1, characterized in that: The mass amounts of the organosilicon-modified cardanol and azobisisobutyronitrile are 6-10% and 0.2-0.5% of the mass amount of the liquid polyisoprene rubber, respectively.

3. The super wear-resistant and non-slip rubber sole material according to claim 1, characterized in that: In the step (1), the molar amounts of 4-methoxythiophenol and triethylamine are 102-110% and 150-200% of the molar amount of dimethylvinylchlorosilane, respectively.

4. The super wear-resistant and non-slip rubber sole material according to claim 1, characterized in that: In the step (1), the reaction temperature is 35-50° C. and the reaction time is 12-24 h.

5. The super wear-resistant and non-slip rubber sole material according to claim 1, characterized in that: In step (2), the molar amounts of the 4-methoxyphenylchlorosilane intermediate and sodium hydride are 110-130% and 120-150% of the molar amount of cardanol, respectively.

6. The super wear-resistant and non-slip rubber sole material according to claim 1, characterized in that: In step (2), the reaction temperature is 60-80° C. and the reaction time is 5-12 h.

7. The super wear-resistant and non-slip rubber sole material according to claim 1, characterized in that: The molar amount of boron tribromide in step (3) is 150-220% of the molar amount of 4-methoxyphenylsilane-modified cardanol.

8. A method for preparing the super wear-resistant and non-slip rubber sole material according to any one of claims 1 to 7, characterized in that: The preparation method comprises the following steps: adding natural rubber to an open mill and mixing it over a roller; adding epoxidized natural rubber, white carbon black, silicon-containing cardanol grafted polyisoprene rubber, stearic acid, and zinc oxide for mixing at a mixing temperature of 50-70° C.; then adding an accelerator, sulfur, and an antioxidant; mixing the mixture thoroughly and leaving the mixture to stand for 5-12 hours; and then vulcanizing the mixture in a flat vulcanizer to obtain a super wear-resistant and anti-skid rubber sole material.

9. The method for preparing the super wear-resistant and non-slip rubber sole material according to claim 8, characterized in that: The vulcanization temperature is 115-130° C., the vulcanization pressure is 20-30 MPa, and the vulcanization time is 5-10 minutes.

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