Shock-absorbing and soothing material for shoe sole, preparation method of shock-absorbing and soothing material and prepared shoe sole

Abstract

The invention relates to the technical field of sole materials, in particular to a damping and soothing material for a sole, a preparation method of the damping and soothing material and the prepared sole. The damping and soothing material for the shoe sole is prepared from the following raw materials in parts by mass: 60 to 100 parts of ethylene-vinyl acetate copolymer, 5 to 15 parts of low-density polyethylene, 40 to 60 parts of carboxy nitrile rubber, 1 to 10 parts of functionalized graphene, 0.01 to 0.1 part of carbodiimide, 50 to 80 parts of reinforcing agent, 5 to 15 parts of active agent, 1 to 2 parts of stearic acid, 1 to 2 parts of antioxidant, 1 to 2 parts of vulcanizing agent, 0.1 to 1.5 parts of accelerant and 5 to 10 parts of foaming agent. The functionalized graphene is prepared from the following raw materials: graphene oxide, methyl acrylate and ethidene diamine, and the mass ratio of the graphene oxide to the methyl acrylate to the ethidene diamine is (1-5): (1-3): (2-5). The stable performance of the sole is guaranteed, and the sole has high rebound resilience and low compression deformation rate.

Description

Technical Field

[0001] The present invention relates to the technical field of sole materials, and in particular to a shock-absorbing and soothing material for soles, a preparation method thereof, and the prepared sole. Background Art

[0002] In today's finished footwear industry, leather shoes and casual shoes, as staples of daily wear, are attracting increasing consumer attention for their comfort and health benefits. Good shock absorption improves comfort, cushions the body from impact during exercise, and protects bones and joints from damage. However, the sole materials of mainstream leather and casual shoes currently on the market are often relatively hard, failing to provide adequate cushioning and support for the foot during wear.

[0003] As people increasingly prioritize their health, demand for comfortable and healthy footwear is growing. Wearing shoes with stiff midsoles for extended periods of time can easily lead to swelling and fatigue in the foot area, severely impacting the wearing experience. Furthermore, existing sole structures struggle to achieve the desired effects of massaging the foot's meridians and promoting blood circulation.

[0004] Currently, the soles of most athletic shoes are made of EVA and its blends. EVA and its blends offer lightweight, warmth, comfort, and low cost. However, existing EVA and its blends have high density and insufficient elasticity. While midsoles for sports like basketball and running require high elasticity, they also suffer from poor wear resistance and slip resistance, which existing EVA foams cannot meet.

[0005] At present, the shock absorption performance of sports shoes mainly focuses on the research of the material and structure of the sole. The structural shock absorption technology is relatively mature, while the material shock absorption is mainly concentrated on the foam midsole and insole of sports shoes. Currently, there is less research on the shock absorption of the sole material.

[0006] Therefore, developing a sole material with light weight, shock absorption, good elasticity and excellent wear resistance has become the main direction of sole research and development. Summary of the Invention

[0007] The purpose of the present invention is to solve the shortcomings of the prior art and to propose a shock-absorbing and soothing material for soles, a preparation method thereof, and the prepared soles.

[0008] A shock-absorbing and soothing material for shoe soles comprises, by weight, 60-100 parts of ethylene-vinyl acetate copolymer, 5-15 parts of low-density polyethylene, 40-60 parts of carboxylated nitrile rubber, 1-10 parts of functionalized graphene, 0.01-0.1 parts of carbodiimide, 50-80 parts of a reinforcing agent, 5-15 parts of an active agent, 1-2 parts of stearic acid, 1-2 parts of an antioxidant, 1-2 parts of a vulcanizing agent, 0.1-1.5 parts of an accelerator, and 5-10 parts of a foaming agent. The raw materials of the functionalized graphene comprise graphene oxide, methyl acrylate, and ethylenediamine, with the mass ratio of graphene oxide, methyl acrylate, and ethylenediamine being 1-5:1-3:2-5.

[0009] Preferably, the reinforcing agent is white carbon black.

[0010] Preferably, the vulcanizing agent is sulfur or dicumyl peroxide.

[0011] Preferably, the active agent is at least one of diethylene glycol, polyethylene glycol, zinc oxide, and magnesium oxide.

[0012] Preferably, the accelerator is at least one of N-cyclohexyl-2-benzothiazole sulfenamide, N-tert-butyl-2-benzothiazole sulfenamide, tetramethylthiuram monosulfide, 2-mercaptobenzothiazole, and tetramethylthiuram disulfide.

[0013] Preferably, the antioxidant is antioxidant 1010 or / and antioxidant 4010NA.

[0014] Preferably, the foaming agent includes an organic foaming agent and an inorganic foaming agent, the organic foaming agent is azodicarbonamide, and the inorganic foaming agent is sodium bicarbonate and / or ammonium bicarbonate.

[0015] Preferably, the functionalized graphene is prepared by the following steps: adding graphene oxide to methanol and ultrasonically treating it for 1-2 hours, adjusting the pH value of the system to 7.2-8, adding ethylenediamine and continuing ultrasonic treatment for 10-30 minutes, adding methyl acrylate dropwise thereto in a stirring state and under nitrogen protection, stirring at 30-50° C. for 20-30 hours, and removing the solvent by reduced pressure distillation; adding methanol and stirring evenly, adding ethylenediamine dropwise thereto in a stirring state and stirring for 20-40 hours, distilling under reduced pressure, vacuum drying, and crushing.

[0016] More preferably, the ultrasound frequency is 30-40 kHz.

[0017] The method for preparing the shock-absorbing and soothing material for the sole comprises the following steps:

[0018] S1. Melt and plasticize ethylene-vinyl acetate copolymer and low-density polyethylene at a plasticizing temperature of 90-100° C., add carboxyl nitrile rubber, functionalized graphene, and carbodiimide, and continue to banburying for 1-3 minutes to obtain a prefabricated material;

[0019] S2, add reinforcing agent to the prefabricated material and mix for 1-3 minutes, add active agent, stearic acid, and antioxidant in sequence and mix evenly, add vulcanizing agent, accelerator, and foaming agent and mix for 1-2 minutes, unload, refine, and place at room temperature for 10-20 hours after cutting to obtain a blank;

[0020] S3. The blank is extruded and pelletized, air-cooled, and then fed into a corresponding mold. It is molded into sheets at 130-150°C. After cooling, the blank is stacked and placed in a mold and the mold is closed. The blank is vulcanized at 190-200°C for 1-3 minutes.

[0021] A midsole comprises an outer plate, the upper end of the outer plate being fixedly connected to a die plate, the upper end of the outer plate being provided with a mounting groove, a buffer layer being installed in the mounting groove, the buffer layer comprising foam installed in the mounting groove, the upper end of the foam being provided with a circular foaming, the lower end of the mounting groove being provided with a through opening, the lower end of the foam being fixedly connected to a bottom protrusion, and the bottom protrusion passing through the through opening; the material used for the foam is the above-mentioned shock-absorbing and soothing material for the sole.

[0022] Preferably, a plurality of connection grooves are provided at the lower end of the outer plate, an anti-slip layer and a plurality of corrugated blocks are fixedly connected to the upper end of the outer plate, and an inner groove is provided at the lower end of the outer plate.

[0023] Preferably, the length of the circular foam is 39.5 mm, the width of the circular foam is 30 mm, and the height of the circular foam is 6 mm.

[0024] Preferably, the inner and outer walls on the left and right sides of the die plate are both arc-shaped, the arc radius of the inner wall of the die plate is 4mm, the arc radius of the outer wall of the die plate is 1.5mm, the left and right wall thickness of the die plate is 2.3mm, and the distance between the outer side of the die plate and the outer side of the outer plate is 4mm.

[0025] Preferably, a portion of the inner walls on the left and right sides of the through hole are arc surfaces, the height of the arc surfaces is 1.5 mm, and the distance between the inner top of the inner groove and the inner bottom of the mounting groove is 3 mm.

[0026] Preferably, the circular foam and the foam are bonded by hot melt adhesive.

[0027] Beneficial effects:

[0028] The present invention uses ethylene-vinyl acetate copolymer as a matrix for foaming, and cooperates with low-density polyethylene and carboxyl nitrile rubber to make the foam material of the present invention have good toughness, but lacks hardness and compression deformation resistance. The present invention adds functionalized graphene and makes it stably and evenly distributed in the matrix. After foaming, the density is reduced, and the sole material used has good resilience and excellent compression deformation resistance.

[0029] The present invention utilizes ethylenediamine small molecules to be intercalated between graphene oxide layers, and polymerizes between graphene sheets through an in-situ polymerization method to generate a dendritic molecular structure, which can not only prevent the graphene oxide from agglomerating, but also promote the graphene oxide to be uniformly dispersed between carboxyl nitrile rubbers. The carboxylic acid groups on the carboxyl nitrile rubber molecular chains can combine with amino groups on the surface of functionalized graphene to form chemical bonds at a banburying temperature. At the same time, the amino groups on the surface of the functionalized graphene and the silanol groups of white carbon black enhance interfacial bonding through hydrogen bonding. At the same time, the white carbon black forms a three-dimensional network structure in the rubber matrix, which synergistically improves the rigidity of the material with the layered distribution of the functionalized graphene, thereby achieving a rigid-elastic balance. The above-mentioned various effects synergistically improve the dimensional stability of the product, so that the product has good compression deformation resistance. Moreover, the layered structure of the functionalized graphene cooperates with the porous foaming structure to significantly enhance the shock absorption effect of the present invention, and the shock absorption effect is longer-lasting, and the shock absorption effect for shoe soles is excellent.

[0030] The sole material prepared by the present invention has a strong bonding force between the raw materials, which prevents precipitation from the finished product, ensuring stable performance of the sole and extending the service life of the sports shoes. The sole material also has a low compression deformation rate, high resilience, good right-angle tear strength, and suitable material hardness, providing high wearing comfort. The preparation method of the present invention is simple, the raw materials are readily available, and the purpose of energy conservation and environmental protection can be achieved.

[0031] The present invention also provides a midsole, wherein the foam material used is the aforementioned shock-absorbing and soothing material for soles. By providing a cushioning layer structure comprising foam and circular foaming, the present invention can provide a more excellent shock-absorbing effect and more targeted heel massage, promoting blood circulation in the heel and improving the user's comfort and fatigue resistance. Furthermore, by adopting the curved design of the inner wall of the die plate and the provision of an anti-slip layer and corrugated blocks on the outer plate, the present invention ensures that the resulting midsole not only has excellent shock-absorbing and massaging functions but also remains stable in actual use, thereby improving the product's practicality and durability. BRIEF DESCRIPTION OF THE DRAWINGS

[0032] Figure 1 This is a comparison chart of the tensile strength and elongation at break of the shock-absorbing and soothing materials obtained in Example 5 and Comparative Examples 1-2.

[0033] Figure 2 This is a comparison chart of the hardness and right-angle tear strength of the shock-absorbing and soothing materials obtained in Example 5 and Comparative Examples 1-2.

[0034] Figure 3 This is a comparison chart of the rebound resilience and compression permanent deformation rate of the shock-absorbing and soothing materials obtained in Example 5 and Comparative Examples 1-2.

[0035] Figure 4 This is a comparison chart of the damping coefficients of the shock-absorbing and soothing materials obtained in Example 5 and Comparative Examples 1-2.

[0036] Figure 5 This is a schematic structural diagram of a midsole of a shoe sole proposed by the present invention;

[0037] Figure 6 for Figure 5 A partial top view of

[0038] Figure 7 A top view of the outer plate 5 as a whole;

[0039] Figure 8 for Figure 7 Bottom view of .

[0040] Figures 5 to 8 Middle: 1 outer plate, 2 die plate, 3 foam, 4 corrugated block, 5 anti-slip layer, 6 bottom protrusion, 7 round foam, 8 connecting groove, 9 installation groove, 10 inner groove. DETAILED DESCRIPTION

[0041] The present invention will be further explained below with reference to specific embodiments.

[0042] The ethylene-vinyl acetate copolymer used below was sourced from Yanshan Petrochemical Company, with the designation 14J4. The low-density polyethylene was sourced from Daqing Petrochemical Company, with the designation 18D. The carboxylated nitrile rubber was purchased from Jining Fangmou Chemical Company.

[0043] Example 1

[0044] A shock-absorbing and soothing material for shoe soles, comprising raw materials of 600 g of ethylene-vinyl acetate copolymer, 50 g of low-density polyethylene, 400 g of carboxylated nitrile rubber, 10 g of functionalized graphene, 0.1 g of carbodiimide, 500 g of white carbon black, 50 g of diethylene glycol, 10 g of stearic acid, 10 g of antioxidant 1010, 10 g of dicumyl peroxide, 1 g of N-cyclohexyl-2-benzothiazole sulfenamide, and 50 g of a foaming agent.

[0045] The foaming agent is composed of azodicarbonamide and sodium bicarbonate or / and ammonium bicarbonate in a mass ratio of 3:7.

[0046] Functionalized graphene was prepared by the following steps: 10 g of graphene oxide was added to 200 g of methanol and ultrasonically treated for 1 hour at an ultrasonic frequency of 30 kHz. The pH value of the system was adjusted to 7.2-8. 10 g of ethylenediamine was added and ultrasonically treated for 10 minutes. 10 g of methyl acrylate was added dropwise under stirring and nitrogen protection, and the mixture was stirred at 30° C. for 20 hours. The solvent was removed by reduced pressure distillation. 200 g of methanol was added and stirred evenly. 10 g of ethylenediamine was added dropwise under stirring and stirred for 20 hours. The mixture was distilled under reduced pressure, dried in a vacuum, and crushed.

[0047] The method for preparing the shock-absorbing and soothing material for the sole comprises the following steps:

[0048] S1. Ethylene-vinyl acetate copolymer and low-density polyethylene are fed into an internal mixer for melt plasticization at a mixer temperature of 90° C. and a mixer speed of 50 r / min. Carboxyl nitrile rubber, functionalized graphene, and carbodiimide are added and the mixture is continuously mixed for 1 min to obtain a prefabricated material;

[0049] S2, adding white carbon black to the prefabricated material and mixing for 1 minute, then adding diethylene glycol, stearic acid, and antioxidant 1010 in sequence and mixing evenly, adding dicumyl peroxide, N-cyclohexyl-2-benzothiazolesulfenamide, and foaming agent and mixing for 1 minute, unloading, feeding into an open mill for sheeting, and placing at room temperature for 10 hours after cutting to obtain a blank;

[0050] S3. The blank is sent to a pelletizer for extrusion and pelletization, and then sent to a corresponding mold after air cooling, and molded into sheets at a temperature of 130°C. After cooling, the blank is stacked and placed in a mold and the mold is closed, and vulcanized at a temperature of 190°C for 1 minute.

[0051] Example 2

[0052] A shock-absorbing and soothing material for shoe soles, whose raw materials include: 1000g of ethylene-vinyl acetate copolymer, 150g of low-density polyethylene, 600g of carboxylated nitrile rubber, 100g of functionalized graphene, 1g of carbodiimide, 800g of white carbon black, 150g of polyethylene glycol, 20g of stearic acid, 20g of antioxidant 4010NA, 20g of sulfur, 15g of 2-thiolbenzothiazole, and 100g of a foaming agent.

[0053] The foaming agent is composed of azodicarbonamide and sodium bicarbonate in a mass ratio of 5:5.

[0054] Functionalized graphene was prepared by the following steps: 50 g of graphene oxide was added to 400 g of methanol and ultrasonically treated for 2 h at an ultrasonic frequency of 40 kHz. The pH value of the system was adjusted to 7.2-8. 30 g of ethylenediamine was added and ultrasonically treated for 30 min. 30 g of methyl acrylate was added dropwise under stirring and nitrogen protection. The mixture was stirred at 50° C. for 30 h, and the solvent was removed by reduced pressure distillation. 400 g of methanol was added and stirred evenly. 20 g of ethylenediamine was added dropwise under stirring and stirred for 40 h, and the mixture was distilled under reduced pressure, dried in a vacuum, and crushed.

[0055] The method for preparing the shock-absorbing and soothing material for the sole comprises the following steps:

[0056] S1. Ethylene-vinyl acetate copolymer and low-density polyethylene are fed into an internal mixer for melt plastication at a mixer temperature of 100° C. and a mixer speed of 70 r / min. Carboxyl nitrile rubber, functionalized graphene, and carbodiimide are added and the mixture is continuously mixed for 3 min to obtain a prefabricated material.

[0057] S2, adding white carbon black to the prefabricated material and mixing for 3 minutes, then adding polyethylene glycol, stearic acid, and antioxidant 4010NA in sequence and mixing evenly, adding sulfur, 2-mercaptobenzothiazole, and foaming agent and mixing for 2 minutes, unloading, feeding into an open mill for sheeting, and placing at room temperature for 20 hours after cutting to obtain a blank;

[0058] S3. The blank is sent to a pelletizer for extrusion and pelletization, and then sent to a corresponding mold after air cooling, and molded into sheets at a temperature of 150°C. After cooling, the blank is stacked and placed in a mold and the mold is closed, and vulcanized at a temperature of 200°C for 3 minutes.

[0059] Example 3

[0060] A shock-absorbing and soothing material for shoe soles, whose raw materials include: 700g of ethylene-vinyl acetate copolymer, 120g of low-density polyethylene, 450g of carboxyl nitrile rubber, 70g of functionalized graphene, 0.3g of carbodiimide, 700g of white carbon black, 80g of zinc oxide, 17g of stearic acid, 101012g of antioxidant, 18g of sulfur, 5g of N-tert-butyl-2-benzothiazole sulfenamide, and 90g of a foaming agent.

[0061] The foaming agent is composed of azodicarbonamide and ammonium bicarbonate in a mass ratio of 3.5:6.5.

[0062] Functionalized graphene was prepared by the following steps: 20 g of graphene oxide was added to 350 g of methanol and ultrasonically treated for 80 min at an ultrasonic frequency of 39 kHz. The pH value of the system was adjusted to 7.2-8. 15 g of ethylenediamine was added and ultrasonically treated for 25 min. 15 g of methyl acrylate was added dropwise under stirring and nitrogen protection. The mixture was stirred at 45° C. for 22 h, and the solvent was removed by reduced pressure distillation. 350 g of methanol was added and stirred evenly. 13 g of ethylenediamine was added dropwise under stirring and stirred for 35 h, and the mixture was distilled under reduced pressure, dried in a vacuum, and crushed.

[0063] The method for preparing the shock-absorbing and soothing material for the sole comprises the following steps:

[0064] S1. Ethylene-vinyl acetate copolymer and low-density polyethylene are fed into an internal mixer for melt plastication at a mixer temperature of 92° C. and a mixer speed of 65 r / min. Carboxyl nitrile rubber, functionalized graphene, and carbodiimide are added and the mixture is further mixed for 1.5 min to obtain a prefabricated material.

[0065] S2, adding white carbon black to the prefabricated material and mixing for 2.5 minutes, then adding zinc oxide, stearic acid, and antioxidant 1010 in sequence and mixing evenly, adding sulfur, N-tert-butyl-2-benzothiazolesulfenamide, and foaming agent and mixing for 1.5 minutes, unloading, feeding into an open mill for sheeting, and placing at room temperature for 12 hours after cutting to obtain a blank;

[0066] S3. The blank is sent to a pelletizer for extrusion and pelletization, and then sent to a corresponding mold after air cooling, and molded into sheets at a temperature of 145°C. After cooling, the blank is stacked and placed in a mold and the mold is closed, and vulcanized at a temperature of 192°C for 2.5 minutes.

[0067] Example 4

[0068] A shock-absorbing and soothing material for shoe soles, whose raw materials include: 900g of ethylene-vinyl acetate copolymer, 80g of low-density polyethylene, 550g of carboxylated nitrile rubber, 30g of functionalized graphene, 0.7g of carbodiimide, 600g of white carbon black, 120g of zinc oxide, 13g of stearic acid, 18g of antioxidant 4010NA, 14g of sulfur, 12g of tetramethylthiuram monosulfide, and 70g of a foaming agent.

[0069] The foaming agent is composed of azodicarbonamide and ammonium bicarbonate in a mass ratio of 4.5:5.5.

[0070] Functionalized graphene was prepared by the following steps: 40 g of graphene oxide was added to 250 g of methanol and ultrasonically treated for 100 min at an ultrasonic frequency of 33 kHz. The pH value of the system was adjusted to 7.2-8. 25 g of ethylenediamine was added and ultrasonically treated for 15 min. 25 g of methyl acrylate was added dropwise under stirring and nitrogen protection. The mixture was stirred at 35° C. for 28 h, and the solvent was removed by reduced pressure distillation. 250 g of methanol was added and stirred evenly. 17 g of ethylenediamine was added dropwise under stirring and stirred for 25 h, and the mixture was distilled under reduced pressure, dried in a vacuum, and crushed.

[0071] The method for preparing the shock-absorbing and soothing material for the sole comprises the following steps:

[0072] S1. Ethylene-vinyl acetate copolymer and low-density polyethylene are fed into an internal mixer for melt plastication at a mixer temperature of 98° C. and a mixer speed of 55 r / min. Carboxyl nitrile rubber, functionalized graphene, and carbodiimide are added and the mixture is continuously mixed for 2.5 min to obtain a prefabricated material.

[0073] S2, adding white carbon black to the prefabricated material and mixing for 1.5min, then adding zinc oxide, stearic acid and antioxidant 4010NA in sequence and mixing evenly, adding sulfur, tetramethylthiuram monosulfide and foaming agent and mixing for 1.5min, unloading, sending to the open mill for refining, cutting and placing at room temperature for 18h to obtain the blank;

[0074] S3. The blank is sent to a pelletizer for extrusion and pelletization, and then sent to a corresponding mold after air cooling, and molded into sheets at a temperature of 135°C. After cooling, the blank is stacked and placed in a mold and the mold is closed, and vulcanized at a temperature of 198°C for 1.5 minutes.

[0075] Example 5

[0076] A shock-absorbing and soothing material for shoe soles, whose raw materials include: 800g of ethylene-vinyl acetate copolymer, 100g of low-density polyethylene, 500g of carboxylated nitrile rubber, 50g of functionalized graphene, 0.5g of carbodiimide, 650g of white carbon black, 100g of zinc oxide, 15g of stearic acid, 101015g of antioxidant, 16g of sulfur, 8g of tetramethylthiuram disulfide, and 80g of foaming agent.

[0077] The foaming agent is composed of azodicarbonamide and ammonium bicarbonate in a mass ratio of 4:6.

[0078] Functionalized graphene was prepared by the following steps: 30 g of graphene oxide was added to 300 g of methanol and ultrasonically treated for 90 min at an ultrasonic frequency of 36 kHz. The pH value of the system was adjusted to 7.2-8. 20 g of ethylenediamine was added and ultrasonically treated for 20 min. 20 g of methyl acrylate was added dropwise under stirring and nitrogen protection. The mixture was stirred at 40° C. for 25 h, and the solvent was removed by reduced pressure distillation. 300 g of methanol was added and stirred evenly. 15 g of ethylenediamine was added dropwise under stirring and stirred for 30 h, and the mixture was distilled under reduced pressure, dried in a vacuum, and crushed.

[0079] The method for preparing the shock-absorbing and soothing material for the sole comprises the following steps:

[0080] S1. Ethylene-vinyl acetate copolymer and low-density polyethylene are fed into an internal mixer for melt plastication at a mixer temperature of 95° C. and a mixer speed of 60 r / min. Carboxyl nitrile rubber, functionalized graphene, and carbodiimide are added and the mixture is continuously mixed for 2 min to obtain a prefabricated material.

[0081] S2, add white carbon black to the prefabricated material and mix for 2 minutes, then add zinc oxide, stearic acid and antioxidant 1010 in sequence and mix evenly, add sulfur, tetramethylthiuram disulfide and foaming agent and mix for 1.5 minutes, unload, send to open mill for sheeting, and leave at room temperature for 15 hours after cutting to obtain blank;

[0082] S3. The blank is sent to a pelletizer for extrusion and pelletization, and then sent to a corresponding mold after air cooling, and molded into sheets at a temperature of 140°C. After cooling, the blank is stacked and placed in a mold and the mold is closed, and vulcanized at a temperature of 195°C for 2 minutes.

[0083] Comparative Example 1

[0084] A shock-absorbing and soothing material for shoe soles, whose raw materials include: 800g of ethylene-vinyl acetate copolymer, 100g of low-density polyethylene, 500g of carboxylated nitrile rubber, 50g of graphene oxide, 0.5g of carbodiimide, 650g of white carbon black, 100g of zinc oxide, 15g of stearic acid, 101015g of antioxidant, 16g of sulfur, 8g of tetramethylthiuram disulfide, and 80g of foaming agent.

[0085] The foaming agent is composed of azodicarbonamide and ammonium bicarbonate in a mass ratio of 4:6.

[0086] The method for preparing the shock-absorbing and soothing material for the sole comprises the following steps:

[0087] S1. Ethylene-vinyl acetate copolymer and low-density polyethylene are fed into an internal mixer for melt plasticization at a mixer temperature of 95° C. and a mixer speed of 60 r / min. Carboxyl nitrile rubber, graphene oxide, and carbodiimide are added and the mixture is continuously mixed for 2 min to obtain a prefabricated material.

[0088] S2, add white carbon black to the prefabricated material and mix for 2 minutes, then add zinc oxide, stearic acid and antioxidant 1010 in sequence and mix evenly, add sulfur, tetramethylthiuram disulfide and foaming agent and mix for 1.5 minutes, unload, send to open mill for sheeting, and leave at room temperature for 15 hours after cutting to obtain blank;

[0089] S3. The blank is sent to a pelletizer for extrusion and pelletization, and then sent to a corresponding mold after air cooling, and molded into sheets at a temperature of 140°C. After cooling, the blank is stacked and placed in a mold and the mold is closed, and vulcanized at a temperature of 195°C for 2 minutes.

[0090] Comparative Example 2

[0091] A shock-absorbing and soothing material for shoe soles, whose raw materials include: 800g of ethylene-vinyl acetate copolymer, 100g of low-density polyethylene, 500g of carboxylated nitrile rubber, 50g of functionalized graphene, 0.5g of carbodiimide, 650g of white carbon black, 100g of zinc oxide, 15g of stearic acid, 101015g of antioxidant, 16g of sulfur, 8g of tetramethylthiuram disulfide, and 80g of foaming agent.

[0092] The foaming agent is composed of azodicarbonamide and ammonium bicarbonate in a mass ratio of 4:6.

[0093] Functionalized graphene was prepared by the following steps: 30 g of graphene oxide was added to 300 g of methanol and ultrasonically treated for 90 min at an ultrasonic frequency of 36 kHz. The pH value of the system was adjusted to 7.2-8. 20 g of ethylenediamine was added and ultrasonically treated for 20 min. 20 g of methyl acrylate was added dropwise under stirring and nitrogen protection. The mixture was stirred at 40° C. for 25 h, and the solvent was removed by reduced pressure distillation. 300 g of methanol was added and stirred evenly. 15 g of ethylenediamine was added dropwise under stirring and stirred for 30 h, and the mixture was distilled under reduced pressure, dried in a vacuum, and crushed.

[0094] The method for preparing the shock-absorbing and soothing material for the sole comprises the following steps:

[0095] S1. Ethylene-vinyl acetate copolymer and low-density polyethylene are fed into an internal mixer for melt plasticization at a mixer temperature of 95° C. and a mixer speed of 60 r / min. Carboxyl nitrile rubber and carbodiimide are added and the mixing is continued for 2 min to obtain a prefabricated material;

[0096] S2, adding white carbon black and functionalized graphene to the prefabricated material and mixing for 2 minutes, then adding zinc oxide, stearic acid and antioxidant 1010 in sequence and mixing evenly, adding sulfur, tetramethylthiuram disulfide and foaming agent and mixing for 1.5 minutes, unloading, sending to the open mill for sheeting, and leaving at room temperature for 15 hours after cutting to obtain the blank;

[0097] S3. The blank is sent to a pelletizer for extrusion and pelletization, and then sent to a corresponding mold after air cooling, and molded into sheets at a temperature of 140°C. After cooling, the blank is stacked and placed in a mold and the mold is closed, and vulcanized at a temperature of 195°C for 2 minutes.

[0098] The tensile strength and elongation at break of the shock-absorbing and soothing materials obtained in Example 5 and Comparative Examples 1-2 were measured with reference to GB / T 528-2009 “Vulcanized rubber or thermoplastic rubber — Determination of tensile stress-strain properties”.

[0099] like Figure 1 As shown, the tensile strength and elongation at break of the shock-absorbing and soothing material obtained in Example 5 are both the highest, which are better than those of Comparative Examples 1-2 (P < 0.05).

[0100] The hardness of the shock-absorbing and soothing materials obtained in Example 5 and Comparative Examples 1-2 was measured using a Shore C durometer with reference to GB / T 39693.7-2022, "Rubber, vulcanized or thermoplastic rubber — Determination of hardness — Part 7: Apparent hardness of rubber rollers by Shore hardness." The right-angle tear strength of the shock-absorbing and soothing materials obtained in Example 5 and Comparative Examples 1-2 was measured with reference to GB / T 529-2008, "Rubber, vulcanized or thermoplastic rubber — Determination of tear strength (trouser-shaped, right-angled, and crescent-shaped test specimens)."

[0101] like Figure 2 As shown, the shock-absorbing and soothing material obtained in Example 5 has moderate hardness and the highest right-angle tear strength, which is better than that of Comparative Examples 1-2 (P < 0.05).

[0102] The rebound resilience of the shock-absorbing and soothing materials obtained in Example 5 and Comparative Examples 1-2 was measured with reference to GB / T 1681-2009, "Determination of Rebound Resilience of Vulcanized Rubber." The compression set of the shock-absorbing and soothing materials obtained in Example 5 and Comparative Examples 1-2 was measured with reference to HG / T 2876-2009, "Test Method for Compression Deformation of Microporous Rubber and Plastic Footwear Materials."

[0103] like Figure 3As shown, the shock-absorbing and soothing material obtained in Example 5 has the largest rebound resilience and the smallest compression permanent deformation rate, which is better than that of Comparative Examples 1-2 (P < 0.05).

[0104] The damping coefficients of the shock absorbing and soothing materials obtained in Example 5 and Comparative Examples 1-2 were measured using a dynamic thermomechanical analyzer (DMTS). Figure 4 As shown,

[0105] like Figure 4 As shown, the damping coefficient of the shock-absorbing and soothing material obtained in Example 5 is the largest, which is better than that of Comparative Examples 1-2 (P < 0.05).

[0106] The applicant believes that this is because the present invention uses ethylene-vinyl acetate copolymer as the matrix for foaming, combined with low-density polyethylene and carboxyl nitrile rubber, so that the foamed material of the present invention has good toughness and low hardness; the present invention also adds functionalized graphene and makes it stably and evenly distributed in the matrix, and the density is reduced after foaming, so that the sole material has good compression resilience and excellent compression recovery resistance. The present invention utilizes ethylenediamine small molecules to be intercalated between graphene oxide layers, and polymerizes between graphene sheets through an in-situ polymerization method to generate a dendritic molecular structure, which can not only prevent the graphene oxide from agglomerating, but also promote the graphene oxide to be uniformly dispersed between carboxyl nitrile rubbers. The carboxylic acid groups on the carboxyl nitrile rubber molecular chains can combine with amino groups on the surface of functionalized graphene to form chemical bonds at a banburying temperature. At the same time, the functionalized graphene cooperates with white carbon black, and the amino groups on its surface and the silanol groups of the white carbon black form an interpenetrating network through hydrogen bonding, synergistically improving the interfacial bonding strength of the matrix. The above-mentioned various effects synergistically improve the dimensional stability of the product, so that the product has good wear resistance. In addition, the layered structure of the functionalized graphene cooperates with the porous foaming structure to significantly enhance the shock absorption effect of the present invention, and the shock absorption effect is longer-lasting, and the shock absorption effect for shoe soles is excellent.

[0107] Example 6

[0108] Reference Figures 5 to 8, a midsole of a sole, comprising an outer plate 1, the outer plate 1 serving as the basic structural part of the midsole, the material of which has certain strength and wear resistance, and can provide stable support for the entire midsole, the upper end of the outer plate 1 is fixedly connected to a die plate 2, the upper end of the outer plate 1 is provided with a mounting groove 9, a buffer layer is installed in the mounting groove 9, the buffer layer comprises a foam 3 installed in the mounting groove 9, the material used for the foam 3 is the shock-absorbing and soothing material for the sole obtained in Example 5, which is tightly filled in the mounting groove 9 and gives full play to the buffering effect, the upper end of the foam 3 is provided with a circular foam 7, the circular foam 7 is made of foam material, the circular foam 7 is arranged at the upper end of the foam 3, its unique circular shape design can more accurately massage specific parts of the sole of the foot, further enhance the health care function of the midsole, and is used in conjunction with the foam 3 to enhance the overall performance of the midsole, the circular foam 7 and the foam 3 are bonded by hot melt adhesive, and the hot melt adhesive bonding method is adopted to make the circular foam 7 and the foam The cotton 3 can be firmly connected together, the hot melt adhesive has good adhesion and stability, and can maintain a good bonding effect at different ambient temperatures, ensuring that the two will not be easily separated during use. A through hole is provided at the lower end of the mounting groove 9, and the lower end of the foam 3 is fixedly connected to a bottom protrusion 6, which passes through the through hole. A plurality of connecting grooves 8 are provided at the lower end of the outer plate 1, and the plurality of connecting grooves 8 are evenly distributed at the lower end of the outer plate 1. The function of these connecting grooves 8 is to facilitate the connection between the midsole and the sole or other components. The upper end of the outer plate 1 is fixedly connected to an anti-slip layer 5 and a plurality of corrugated blocks 4, and the anti-slip layer 5 and the plurality of corrugated blocks 4 are fixed to the upper end of the outer plate 1. The anti-slip layer 5 can effectively increase the friction between the midsole and the insole, preventing the insole from sliding on the midsole, and the plurality of corrugated blocks 4 further enhance the friction of the midsole surface, while also having a certain massage effect on the sole of the foot, thereby improving the comfort of wearing. An inner groove 10 is provided at the lower end of the outer plate 1.

[0109] Among them, the length of the circular foam 7 is 39.5mm, which can ensure that the circular foam 7 covers the appropriate area when massaging the sole of the foot and provides an effective massage effect. At the same time, it will not affect other functions of the midsole due to being too long. The width of the circular foam 7 is 30mm, and the height of the circular foam 7 is 6mm. When playing the role of shock absorption, it also plays the role of internal height increase. The inner and outer walls on the left and right sides of the mold plate 2 are both arc-shaped. The arc design of the mold plate 2 is not only more beautiful in appearance, but also in actual use. This arc structure The structure can better fit the shape of the foot, reduce friction and pressure on the foot, improve wearing comfort, and also help to improve the overall structural strength of the midsole. The inner wall arc radius of the die plate 2 is 4mm, the outer wall arc radius of the die plate 2 is 1.5mm, the left and right wall thicknesses of the die plate 2 are 2.3mm, the outer side of the die plate 2 and the outer side of the outer plate 1 are 4mm apart, a part of the inner wall on the left and right sides of the through hole is an arc surface, the height of the arc surface is 1.5mm, and the distance between the inner top of the inner groove 10 and the inner bottom of the mounting groove 9 is 3mm.

[0110] The above description is only a preferred specific embodiment of the present invention, but the scope of protection of the present invention is not limited thereto. Any technician familiar with the technical field, within the technical scope disclosed by the present invention, who makes equivalent replacements or changes based on the technical solution and inventive concept of the present invention, should be covered by the scope of protection of the present invention.

Claims

1. A shock-absorbing and soothing material for shoe soles, characterized in that: The raw materials include, by mass: 60-100 parts of ethylene-vinyl acetate copolymer, 5-15 parts of low-density polyethylene, 40-60 parts of carboxylated nitrile rubber, 1-10 parts of functionalized graphene, 0.01-0.1 parts of carbodiimide, 50-80 parts of reinforcing agent, 5-15 parts of active agent, 1-2 parts of stearic acid, 1-2 parts of antioxidant, 1-2 parts of vulcanizing agent, 0.1-1.5 parts of accelerator, and 5-10 parts of foaming agent. The raw materials of the functionalized graphene include: graphene oxide, methyl acrylate and ethylenediamine, and the mass ratio of the graphene oxide, methyl acrylate and ethylenediamine is 1-5:1-3:2-5.

2. The shock-absorbing and soothing material for shoe soles according to claim 1, characterized in that: The reinforcing agent is white carbon black; the vulcanizing agent is sulfur or dicumyl peroxide.

3. The shock-absorbing and soothing material for shoe soles according to claim 1, characterized in that: The active agent is at least one of diethylene glycol, polyethylene glycol, zinc oxide and magnesium oxide.

4. The shock-absorbing and soothing material for shoe soles according to claim 1, characterized in that: The accelerator is at least one of N-cyclohexyl-2-benzothiazole sulfenamide, N-tert-butyl-2-benzothiazole sulfenamide, tetramethylthiuram monosulfide, 2-mercaptobenzothiazole, and tetramethylthiuram disulfide.

5. The shock-absorbing and soothing material for shoe soles according to claim 1, characterized in that: The antioxidant is antioxidant 1010 and / or antioxidant 4010NA.

6. The shock-absorbing and soothing material for shoe soles according to claim 1, characterized in that: The foaming agent includes an organic foaming agent and an inorganic foaming agent. The organic foaming agent is azodicarbonamide, and the inorganic foaming agent is sodium bicarbonate and / or ammonium bicarbonate.

7. The shock-absorbing and soothing material for shoe soles according to claim 1, characterized in that: Functionalized graphene is prepared by the following steps: adding graphene oxide to methanol and ultrasonically treating it for 1-2 hours, adjusting the pH value of the system to 7.2-8, adding ethylenediamine and continuing ultrasonic treatment for 10-30 minutes, adding methyl acrylate dropwise thereto in a stirring state and under nitrogen protection, stirring at 30-50° C. for 20-30 hours, and removing the solvent by reduced pressure distillation; adding methanol and stirring evenly, adding ethylenediamine dropwise thereto in a stirring state and stirring for 20-40 hours, distilling under reduced pressure, vacuum drying, and crushing.

8. The shock-absorbing and soothing material for shoe soles according to claim 7, characterized in that: The ultrasonic frequency is 30-40kHz.

9. A method for preparing the shock-absorbing and soothing material for shoe soles according to any one of claims 1 to 8, characterized in that: The steps include: S1. Melt and plasticize ethylene-vinyl acetate copolymer and low-density polyethylene at a plasticizing temperature of 90-100° C., add carboxyl nitrile rubber, functionalized graphene, and carbodiimide, and continue to banburying for 1-3 minutes to obtain a prefabricated material; S2, add reinforcing agent to the prefabricated material and mix for 1-3 minutes, add active agent, stearic acid, and antioxidant in sequence and mix evenly, add vulcanizing agent, accelerator, and foaming agent and mix for 1-2 minutes, unload, refine, and place at room temperature for 10-20 hours after cutting to obtain a blank; S3. The blank is extruded and pelletized, air-cooled, and then fed into a corresponding mold. It is molded into sheets at 130-150°C. After cooling, the blank is stacked and placed in a mold and the mold is closed. The blank is vulcanized at 190-200°C for 1-3 minutes.

10. A midsole, characterized in that: The outer plate (1) comprises an outer plate (1), the upper end of the outer plate (1) is fixedly connected to a die plate (2), the upper end of the outer plate (1) is provided with a mounting groove (9), a buffer layer is installed in the mounting groove (9), the buffer layer comprises a foam (3) installed in the mounting groove (9), the upper end of the foam (3) is provided with a circular foam (7), the lower end of the mounting groove (9) is provided with a through opening, the lower end of the foam (3) is fixedly connected to a bottom protrusion (6), and the bottom protrusion (6) passes through the through opening; The material used for the foam (3) is the shock-absorbing and soothing material for the sole as claimed in any one of claims 1 to 9.

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