One-piece multifunctional sole and preparation method thereof

Abstract

The invention discloses an integrally formed multifunctional sole and a preparation method thereof, belonging to the field of footwear products, the method comprising: a first midsole material and a second midsole material are once shot by a two-color shooting device to obtain a midsole blank; in the first midsole material, ethylene-vinyl acetate copolymer, ethylene-butyl acrylate copolymer, random polyolefin, styrene-butadiene-styrene block copolymer, ethylene-butyl acrylate-maleic anhydride copolymer are used as matrix resins; the midsole blank and the coated raw rubber sheet are molded and pressed, so that the midsole blank is foamed and cross-linked at high temperature, and the raw rubber sheet is vulcanized and cross-linked at the same temperature; the coated raw rubber sheet is mainly a mixed rubber sheet with rare earth cis-butyl rubber, natural rubber, polyacrylate rubber, and brominated butyl rubber as the main body. The present invention can form a two-color sole foaming and cross-linking and rubber raw rubber vulcanization integrated molding, simplify the process, reduce costs, and improve the production environment.

Description

Technical Field

[0001] The invention belongs to the field of footwear products, and in particular relates to an integrally formed multifunctional sole and a preparation method thereof. Background Art

[0002] As we all know, the soles of some sports shoes generally include a rubber outsole and a foamed midsole. The rubber outsole directly touches the ground and is mainly wear-resistant. The foamed midsole plays a supporting and rebounding role. The traditional preparation process requires the midsole to be foamed and the outsole to be vulcanized, and then the two are bonded together through some combination processes. There are currently two methods of combination. One of the traditional combination methods is manual bonding, and its full process includes: roughing the midsole, cleaning the midsole, drying the midsole, roughing the outsole, cleaning the outsole, drying the outsole, brushing the outsole with a treatment agent-baking-brushing glue-baking-pressing and other processes. The entire production process requires complicated processes, a large amount of manpower and a large amount of glue solution, which is not only time-consuming and labor-intensive, but also has low production efficiency and high production costs. At the same time, the harmful substances in the treatment agent and glue used in the production process are extremely detrimental to the environment and the health of workers. The other is an improved one-piece molding process, which is to mold the foamed EVA midsole and the unvulcanized rubber sole into one piece through hot melt adhesive film molding; or to foam the vulcanized rubber sole with polyurethane foaming stock solution and hot melt adhesive film again. However, both the traditional combination method and the improved one-piece molding method have their own shortcomings.

[0003] Secondly, most sports shoe midsoles are single-color single-function foams. In order to enhance the aesthetics and / or increase the diversity of functions, there are usually three methods: one is to achieve two or more colors in appearance through spray painting, but the density / hardness / rebound / compression of the sole is single; the second is to achieve different appearances and functions by processing the upper and lower layers or the forefoot and rearfoot, inner and outer layers in batches, but this method requires processing different parts twice or more and then combining and bonding, and there are many processes; the third is to prepare through a two-color injection machine or a two-color molding machine. This method achieves high-efficiency production of two-color multifunctional foam soles, but cannot achieve one-piece molding with the outsole. It still needs to be bonded with the outsole through a combined process, which makes it difficult to improve production efficiency. Summary of the invention

[0004] In view of this, the present invention provides an integrally molded multifunctional sole and a preparation method thereof. The present invention can streamline the production process, reduce production costs, and improve the production environment by integrating the foaming and cross-linking of the two-color sole with the vulcanization of the rubber raw rubber, thereby avoiding the pollution of the environment by glue and paint and the harm to the health of employees.

[0005] The present invention provides a method for preparing an integrally formed multifunctional sole, comprising the following steps:

[0006] The first midsole material and the second midsole material are injected once by a two-color injection device to obtain a midsole blank; the first midsole material uses ethylene-vinyl acetate copolymer, ethylene-butyl acrylate copolymer, random polyolefin, styrene-butadiene-styrene block copolymer and ethylene-butyl acrylate-maleic anhydride copolymer as the base resin, and the second midsole material uses ethylene-vinyl acetate copolymer, ethylene-methacrylic acid copolymer, ethylene-butyl acrylate-maleic anhydride copolymer, block polyolefin and ethylene-propylene terpolymer as the base resin;

[0007] The midsole mold blank and the coated raw rubber sheet are molded and pressed in a mold, so that the midsole mold blank is foamed and cross-linked at a high temperature, and the raw rubber sheet is vulcanized and cross-linked at the same temperature to obtain an integrally molded multifunctional sole; the coated raw rubber sheet includes: a mixed rubber sheet mainly composed of rare earth butadiene rubber, natural rubber, polyacrylate rubber and brominated butyl rubber, and an EVA hot-melt adhesive film covering the top surface thereof, and the EVA hot-melt adhesive film is in contact with the second midsole material injection structure of the midsole mold blank.

[0008] See also Figure 1 , Figure 1 The figure is a schematic diagram of the molding process flow of an embodiment of the present invention. In the embodiment of the present invention, the first midsole material and the second midsole material can be weighed, kneaded and granulated respectively, and then a two-color injection device is used for one injection to obtain an IP injection two-color small rough blank, which is the midsole blank. At the same time, the rubber material of the outsole can be weighed, mixed into a sheet, and then cut and coated to obtain a coated raw rubber sheet. Finally, the embodiment of the present invention molds the midsole blank and the coated raw rubber sheet in a mold, and the molded foamed midsole and the vulcanized rubber outsole are integrally molded, and the multifunctional sole is obtained after cooling.

[0009] The embodiment of the present invention realizes the preparation of an integrally molded multifunctional sole. In terms of material formulation, the first midsole material corresponds to the upper midsole material, which is mainly used to achieve ultra-soft and extremely high elastic midsole performance. The first midsole material uses matrix resins such as ethylene-vinyl acetate copolymer, ethylene-butyl acrylate copolymer, olefin random polymer, styrene-butadiene-styrene block copolymer, and ethylene-butyl acrylate-maleic anhydride copolymer.

[0010] In addition, the second midsole material corresponds to the lower midsole, which is mainly used to achieve high support and compression resistance of the midsole performance, and the formula materials are selected from base resins such as ethylene-vinyl acetate copolymer, ethylene-methacrylic acid copolymer, ethylene-butyl acrylate-maleic anhydride copolymer, olefin block copolymer, and ethylene-propylene terpolymer.

[0011] The lower layer of the sole is a rubber outsole that directly contacts the ground and has the main performance characteristics of wear resistance and anti-slip; the formula uses base components such as rare earth butadiene rubber, natural rubber, polyacrylate rubber (ACM rubber), brominated butyl rubber, etc.

[0012] The formula of the three-layer structure of the sole described in the embodiment of the present invention contains polar polymers, such as ethylene-vinyl acetate copolymer, ethylene-butyl acrylate copolymer, ethylene-methacrylic acid copolymer, and ethylene-butyl acrylate-maleic anhydride copolymer added in the two-layer midsole material formula, which are all ethylene-ester / acid polymers with strong polarity and high compatibility, which is conducive to enhancing the interfacial force between the two-layer midsole structure. At the same time, the polyacrylate rubber (ACM rubber) in the lower rubber sole not only improves the polarity, but also enhances the compatibility with the EVA hot melt adhesive film, thereby improving the bonding strength, etc. In addition, the hot melt adhesive film of the embodiment of the present invention uses EVA as the base, which can achieve excellent compatibility and interfacial force with both the rubber outsole and the lower layer of the midsole, and improves the bonding strength between the three. Secondly, the formula of the two-layer midsole of the embodiment of the present invention is matched with other polymers, which can achieve different functions such as softness and high elasticity, support and pressure resistance; in addition, a midsole structure of two colors can be obtained.

[0013] Among them, EVA is the English abbreviation of ethylene-vinyl acetate copolymer, which has good strength and elasticity. Compared with polyethylene (PE), EVA introduces vinyl acetate (VA) monomer into the molecular chain, which reduces the high crystallinity and improves flexibility and impact resistance.

[0014] In a specific embodiment of the present invention, the first midsole material includes, by weight: 40-50 parts of ethylene-vinyl acetate copolymer, 10-20 parts of ethylene-butyl acrylate copolymer, 15-25 parts of random polyolefin, 10-15 parts of styrene-butadiene-styrene block copolymer, 5-10 parts of ethylene-butyl acrylate-maleic anhydride copolymer, 0.5-0.6 parts of peroxide crosslinking agent, 3-4 parts of foaming agent, 1.2-1.5 parts of stearic acid, 1.0-1.5 parts of zinc stearate, 0.8-1.2 parts of zinc oxide, 2-3 parts of filler and 0.5-2 parts of optional color particles.

[0015] To be more specific, in the first midsole material, the VA mass content of ethylene-vinyl acetate copolymer is 25-40%, preferably 30-40%; a preferred commercially available brand product such as DuPont's EVA33121 has a VA content of 33%, and its weight parts can be 40 parts, 45 parts, or 50 parts.

[0016] The butyl acrylate content of the ethylene-butyl acrylate copolymer may be 25-30% by mass; a preferred commercially available brand product such as EBA 3427 from DuPont has a butyl acrylate content of 27% and its weight parts may be 10 parts, 15 parts, or 20 parts.

[0017] The ethylene-butyl acrylate-maleic anhydride copolymer has a relatively low content of maleic anhydride, which is a grafted component. The embodiment of the present invention can use an ethylene-butyl acrylate-maleic anhydride copolymer product with a maleic anhydride grafting rate of 1-5%, and the preferred variety is Fusabond A 560 (DuPont, maleic anhydride content 1%), and its weight parts can be 5 parts, 7 parts, 7.5 parts, 8 parts, 9 parts, and 10 parts.

[0018] The random polyolefin is mainly an olefin random copolymer, and its hardness is preferably 50-65A, and further an ethylene-octene random copolymer product with a hardness of 50-65A, wherein the preferred varieties are: POE 8180 (Dow, hardness 63A). POE is generally the English abbreviation of polyolefin elastomer, including ethylene-octene random copolymer, etc., which has good flexibility and resilience. In addition, the weight parts of the olefin random copolymer can be 15 parts, 20 parts, and 25 parts.

[0019] The styrene-butadiene-styrene block copolymer includes products with a styrene content of 20-25% by mass, among which the preferred variety is SEBS P1083 (Asahi Kasei Corporation). SEBS is generally the English abbreviation for a linear triblock copolymer with polystyrene as the terminal segment and ethylene-butene copolymer obtained by hydrogenating polybutadiene as the middle elastic block, and has excellent aging resistance and other properties.

[0020] In addition, the first midsole material of the embodiment of the present invention adopts 0.5-0.6 parts of peroxide crosslinking agent and 3-4 parts of foaming agent; preferably also includes 1.2-1.5 parts of stearic acid, 1.0-1.5 parts of zinc stearate, 0.8-1.2 parts of zinc oxide (ZnO), 2-3 parts of filler and 0.5-2 parts of color particles.

[0021] The peroxide crosslinking agent includes one of diisopropylbenzene peroxide and 1,4-di-tert-butylperoxyisopropylbenzene, and the preferred variety is commercially available BIBP (1,4-di-tert-butylperoxyisopropylbenzene).

[0022] The foaming agent is specifically an azo AC foaming agent, which may include azodicarbonamide, and a preferred variety is the commercially available AC808 foaming agent product.

[0023] As for the active agent, the preferred zinc oxide in the embodiment of the present invention is ZnO 997; the preferred stearic acid is the commercially available 1801 product; zinc stearate may include a brand with a zinc content of 10.5-11.5wt%, and the preferred variety is the commercially available 2818 product.

[0024] The filler described in the embodiment of the present invention preferably includes one of talcum powder, nano-activated calcium carbonate and fumed silica, preferably talcum powder HS818. In addition, the color particles preferably added can be colored or white EVA-based color particles, and commercially available products can be used.

[0025] In a specific embodiment of the present invention, the second midsole material includes, by weight: 40-50 parts of ethylene-vinyl acetate copolymer, 10-25 parts of ethylene-methacrylic acid copolymer, 5-10 parts of ethylene-butyl acrylate-maleic anhydride copolymer, 15-25 parts of block polyolefin, 10-15 parts of ethylene-propylene terpolymer, 0.5-0.6 parts of peroxide crosslinking agent, 3-4 parts of foaming agent, 1.2-1.5 parts of stearic acid, 1.0-1.5 parts of zinc stearate, 0.8-1.2 parts of zinc oxide, 2-3 parts of filler and 0.5-2 parts of optional color particles.

[0026] In the second midsole material, the VA content of ethylene-vinyl acetate copolymer is preferably 15-24%, more preferably 16-23%, wherein further preferred varieties include: EVA 7350 (Formosa Plastics Corporation, China, VA content is 18%). In some embodiments, the weight parts of EVA in the second midsole material are 40 parts, 45 parts or 50 parts.

[0027] The methacrylic acid content of the ethylene-methacrylic acid copolymer may be 5-15%, further 6-12%, 8%, 9%, 10%, etc.; the preferred varieties include: Fusabond 514D (DuPont, methacrylic acid content is 9%). In some embodiments, the weight portion of the ethylene-methacrylic acid copolymer is preferably 12-23 parts, more preferably 15-20 parts.

[0028] The ethylene-butyl acrylate-maleic anhydride copolymer in the second midsole material is the same as that described above, specifically including products with a maleic anhydride grafting rate of 1-5%, and the preferred variety is Fusabond A 560; its weight parts can be 5 parts, 6 parts, 7.5 parts, 8 parts, and 10 parts.

[0029] The block polyolefin is also called olefin block copolymer, and one of its English abbreviations can be OBC, which is mainly an ethylene-octene alternating block structure. Preferably, the melting point of the olefin block copolymer is above 120°C, specifically including ethylene-octene block copolymers with a melting point ≥120°C, such as a melting point of 120~150°C, wherein the preferred commercially available varieties are: OBC 9107 (Dow, melting point 121°C). In some embodiments, the weight parts are 15 parts, 20 parts, and 25 parts, but are not limited thereto.

[0030] The second midsole material includes 10-15 parts by weight of ethylene-propylene terpolymer, which is beneficial to enhance certain support, etc. The ethylene-propylene terpolymer described in some embodiments of the present invention includes products with an ethylene content of 40-50% and an ENB content of 5-8%, among which the preferred varieties include Dow's EPDM 5565, which can be 10 parts, 11 parts, and 15 parts by weight. The EPDM is the abbreviation of ethylene propylene diene monomer rubber, specifically a terpolymer of ethylene, propylene and non-conjugated diene, expressed as ethylene-propylene-non-conjugated diene terpolymer.

[0031] In parts by weight, the second midsole material of some embodiments of the present invention comprises: 0.5-0.6 parts of peroxide crosslinking agent, 3-4 parts of foaming agent, 1.2-1.5 parts of stearic acid, 1.0-1.5 parts of zinc stearate, 0.8-1.2 parts of zinc oxide, 2-3 parts of filler and 0.5-2 parts of color particles. The specific crosslinking foaming system is substantially the same as the composition of the first midsole material, for example, the foaming agent is preferably an AC foaming agent, including azodicarbonamide, and the preferred variety is foaming agent AC 808.

[0032] Accordingly, the preferred varieties of zinc oxide include ZnO 997; the preferred varieties of stearic acid include stearic acid 1801. The zinc stearate preferably includes a grade with a zinc content of 10.5-11.5%, and the specific variety is zinc stearate 2818. Preferably, the filler includes one of talcum powder, nano-activated calcium carbonate, and fumed silica, and more preferably talcum powder HS818. The color particles in the second midsole material are preferably colored or white EVA-based color particles, and their color may be different from the color of the color particles in the first midsole material.

[0033] In the embodiment of the present invention, the first midsole material and the second midsole material are added to a two-color injection device, and a midsole blank is formed by one injection. In the embodiment of the present invention, the two-color injection device is an IP injection machine commonly used in the art; the molding mold temperature is preferably 170-180°C, and the cross-linking time of one injection can be 420-480 seconds, and then naturally cooled to set.

[0034] In some specific embodiments of the present invention, the steps of forming the midsole blank include:

[0035] Weighing materials: According to the dosage of the formula, weigh BIBP and foaming agent as the first group; weigh stearic acid, zinc stearate, zinc oxide, color particles, and fillers as the second group; weigh the remaining materials as the third group.

[0036] Mixing: First, pour the third group of materials into the internal mixer and turn on the machine. When the temperature rises to between 80-85℃, pour in the second group of materials. When the temperature rises to 90-95℃, pour in the third group of materials. When the temperature rises to 100-110℃, pour out the mixed materials.

[0037] Material making: Pour the mixed material into the material making machine (usually a screw extruder), adjust the temperatures of the first, second, third and fourth zones to 75°C, 80°C, 85°C and 90°C respectively, adjust the screw speed to 40-50 rpm, and adjust the cutting speed to 15-20 rpm.

[0038] IP injection of two-color rough blanks: Pour the finished pellets into the two-color IP injection machine, and adjust the temperatures of the first, second, third, fourth, and fifth feeding zones to 84°C, 86°C, 88°C, 90°C, and 92°C respectively; the corresponding injection speeds are 50(±2)-45(±2)-40(±2)-35(±2)-30(±2)%; the injection pressure is 90(±5)-90(±5)-90(±5)-90(±5)-90(±5)bar; the vacuum time is 80±20 seconds; the upper and lower mold temperatures of the molding mold are adjusted to 175±5°C and 175±5°C respectively. The injection material quantity is 100±20g, the injection time is 150±20 seconds, and the vulcanization time is 450±30 seconds; then, the rough blanks of the midsole can be taken out and naturally cooled for 2 hours to finalize.

[0039] Among them, the injection speed of an injection molding machine is displayed as a percentage because it represents the relative value of the maximum speed. In the debugging of the injection molding machine, the speed is expressed as "%", which means that this is a relative value, that is, the current speed is a certain percentage of the maximum speed. For example, an adjustment between 0-99% means that the speed can be adjusted between 0 and the maximum speed1. In some embodiments of the present invention, the current maximum speed of the machine is 300mm / s. In addition, the vulcanization time is: the pellets are directly injected into the mold, and they need to be cross-linked and vulcanized in the mold for about 450s.

[0040] The embodiment of the present invention prepares a raw rubber sheet that is not vulcanized after mixing, and coats the top surface (non-contact surface) of the raw rubber sheet. The raw rubber sheet described in the embodiment of the present invention includes: a mixed rubber sheet mainly composed of rare earth butadiene rubber, natural rubber, polyacrylate rubber (ACM rubber) and brominated butyl rubber.

[0041] In a specific embodiment of the present invention, the materials of the mixed film may include, by weight: 40-50 parts of rare earth butadiene rubber, 15-25 parts of natural rubber, 15-25 parts of polyacrylate rubber, 10-20 parts of brominated butyl rubber and 2-3 parts of sulfur; further include: 40-50 parts of maleic anhydride modified fumed silica, 3-5 parts of processing oil, 1-2 parts of homogenizer, 2-4 parts of silane coupling agent, 2-3 parts of zinc oxide, 1.0-1.2 parts of stearic acid, 0.8-1.0 parts of antioxidant, 1-1.2 parts of antifogging agent, 0.8-1 parts of microcrystalline wax, 0.3-0.5 parts of antioxidant, 0.9-1.1 parts of accelerator DM, 0.4-0.6 parts of accelerator D and 0.05-0.06 parts of accelerator TS; and may also include 0.5-1 parts of colorant.

[0042] Among the materials of the mixed rubber sheet described in the embodiment of the present invention, the rare earth cis-1,4-butadiene rubber is a cis-1,4-butadiene rubber polymerized by a catalytic system with rare earth metal neodymium as the main body, and its strength and wear resistance are better than ordinary cis-1,4-butadiene rubber. The cis-1,4-butadiene content of the rare earth cis-1,4-butadiene rubber is generally above 98%; specifically, it includes cis-1,4-butadiene rare earth rubber products with a cis-1,4-butadiene content of ≥98% and a Mooney viscosity of 63±3 (ML1+4@100℃), and the preferred variety is BR CB22 product of Lanxess, which can be 40 parts, 45 parts, and 50 parts by weight.

[0043] The natural rubber preferably includes commercially available products with a Mooney viscosity of 80±20 (ML1+4@100°C), among which the preferred variety is NR SVR-3L (Vietnam standard rubber), which has good comprehensive properties and is easy to process; its weight parts are, for example, 15 parts, 20 parts, and 25 parts.

[0044] The brominated butyl rubber (BIIR) is an isobutylene-isoprene copolymer elastomer containing active bromine, and has the characteristics of high shock absorption, and its Mooney viscosity is preferably 29-35 (ML1+4@100°C). The brominated butyl rubber described in the specific embodiment of the present invention includes commercially available products with a Mooney viscosity of 32±3 (ML1+4@100°C), among which the preferred variety is BIIR X2 from Lanxess, and the weight parts can be 10 parts, 15 parts, and 20 parts.

[0045] Polyacrylate rubber, also known as acrylic ester rubber, is a high-temperature oil-resistant special rubber. It refers to a homopolymer of acrylic ester, or an elastic copolymer of an alkyl acrylate monomer and a small amount of a monomer with a cross-linking active group, referred to as ACM rubber. The Mooney viscosity of the polyacrylate rubber described in the embodiment of the present invention is preferably 35~45 (ML1+4@100℃); that is, polyacrylate rubber: preferably includes a product with a Mooney viscosity of 40±5 (ML1+4@100℃), among which the optional varieties include ACM-2212 (Duwe Rubber Technology Co., Ltd.) and the like. In some specific embodiments, the ACM rubber is 15 parts by weight, 20 parts by weight, or 25 parts by weight.

[0046] In addition to the above-mentioned base rubber component, the embodiment of the present invention preferably uses 40-50 parts of maleic anhydride modified fumed silica, for example, 40 parts, 45 parts, and 50 parts. Preferably, the maleic anhydride ratio of the maleic anhydride modified fumed silica is 2-3%, and the BET specific surface area is greater than 170m 2 / g, such as 175-185 m 2 / g. That is, the maleic anhydride modified fumed silica includes 2-3% maleic anhydride and has a BET specific surface area of ​​>170m 2 / g varieties, commercially available products can be used.

[0047] In the mixed rubber material described in the embodiment of the present invention, sulfur is used as a crosslinking agent, preferably sulfur S-80. In addition, an accelerator is used to promote the vulcanization process, and the accelerators include sulfonamides, thiazoles, thiurams, guanidines, thioureas and dithiocarbamates; the preferred varieties are a combination of accelerator DM (2,2'-dibenzothiazole disulfide), accelerator D (diphenylguanidine), and accelerator TS (tetramethylthiuram monosulfide).

[0048] To facilitate mixing and processing, the rubber compound material of the embodiment of the present invention includes 3-5 parts by weight of processing oil, which mainly includes paraffin oil and cyclohexane oil, preferably cyclohexane oil. The rubber homogenizer mainly improves the strength and wear resistance of the rubber. The homogenizer preferably added to the rubber compound material of the embodiment of the present invention includes petroleum resins C9 and C5, preferably petroleum resin C5 (which can be called carbon five resin); C5 resin is divided into three types: general type, blending type, and colorless and transparent type, with an average molecular weight of 1000~2500, and the preferred variety is A-172. In addition, the zinc oxide is preferably nano zinc oxide; the preferred variety of stearic acid is 1801 brand product. The rubber compound material of the embodiment of the present invention also introduces a silane coupling agent, which may include vinyl triethoxysilane, vinyl trimethoxysilane, vinyl tri (β-methoxyethoxy) silane) and the like.

[0049] The mixed rubber material of the specific embodiment of the present invention also includes rubber additives such as antioxidant, antioxidant, antifogging agent, etc. to improve the comprehensive performance of the rubber. Among them, the antioxidant is preferably styrenated phenol SP-GR. The antioxidant preferably includes butylated hydroxytoluene BHT; microcrystalline wax can include C25-C30 microcrystalline wax, preferably RW-160. The antifogging agent is preferably a specially designed microcrystalline hydrocarbon mixture, and more preferably a commercially available product of HB-1956 brand.

[0050] In some specific embodiments of the present invention, the steps of forming a coated raw film include:

[0051] Weighing materials: According to the dosage of the formula, weigh the sulfur and accelerator as the first group; weigh the leveling agent, silane coupling agent, zinc oxide, stearic acid, antioxidant, anti-fogging agent, microcrystalline wax, antioxidant and other compounding agents as the second group; weigh the maleic anhydride modified white carbon black as the third group; and weigh the remaining rubber materials as the fourth group.

[0052] Mixing and sheeting: Pour the fourth group of rubber materials into the internal mixer, start the internal mixer, mix for 8-10 minutes, then pour the third group of materials, mix for 10-12 minutes to fully mix the rubber and modified silica, and pour out the mixed mixture when the temperature of the internal mixer rises to 105-110℃. Put the mixed rubber into the open mixer, roll it continuously for 5-10 times, and make it into a 9-11mm thick sheet, park it for 4-8 hours, and stand by. Pour the mixed rubber after parking for 4-8 hours into the internal mixer again, and pour the third group of materials into the internal mixer together, mix for 8-10 minutes, and pour out the mixed rubber when the temperature of the internal mixer rises to 105-110℃. Pour the mixed rubber into the open mixer, roll it continuously for 5-8 times, add accelerator TS and crosslinking agent sulfur, and make it into a 2-3mm thick sheet.

[0053] Cutting: Cut the 2-3mm thick sheet into the size required by the large bottom mold.

[0054] Coating: Cut the EVA hot melt adhesive film into the same shape and size as the rubber sheet, and cover it on the top surface of the cut rubber sheet, then put it into a flat-plate molding vulcanizer, press down the upper mold cover, close the mold, set the temperature to 50-60°C and press for 20-30 seconds, then open the upper mold cover, and then tear off the protective film layer of the EVA hot melt adhesive film to obtain a coated rubber raw rubber sheet. Among them, the bottom surface of the raw rubber sheet contacts the lower mold, and the top surface of the raw rubber sheet is covered with an EVA hot melt adhesive film. Preferably, the EVA hot melt adhesive film comprises a hot melt adhesive film composed of 90-98% EVA, 1-5% maleic anhydride and 1-5% methacrylic acid. Further preferably, the EVA hot melt adhesive film comprises 90% EVA, 5% maleic anhydride and 5% methacrylic acid, and has better hot melt and compatibility.

[0055] Finally, the embodiment of the present invention can mold the two-color midsole blank and the coated raw rubber sheet in a mold of a flat-plate molding vulcanizer to obtain an integrally molded multifunctional sole. In a preferred embodiment of the present invention, the molding temperature is 165-175°C, the time is 570-630 seconds, and then cooled to obtain the finished sole.

[0056] In the embodiment of the present invention, the molded foaming / vulcanization integrated molding is as follows: the cooled two-color sole rough blank is placed on the top surface of the hot melt adhesive film, that is, the hot melt adhesive film is on the top surface of the outsole and on the bottom surface of the midsole; the upper mold cover of the flat mold vulcanizer is pressed down, the mold is closed, and the integrated molding is completed. Preferably, the hot pressing temperature is: 170±5℃; the hot pressing time is: 600±30 seconds.

[0057] The embodiment of the present invention can pull out the one-piece molded sole mold and transfer it to a cooling station, set the cooling water temperature to 23-28° C., and the cooling time to 420±30 seconds; after cooling, take out the one-piece molded two-color multifunctional sole.

[0058] During the molding process of the embodiment of the present invention, the two-layer structure of the midsole mold is foamed and cross-linked at high temperature, and the rubber raw sheet is vulcanized and cross-linked at the same temperature. During the foaming and vulcanization processes, the integrated foaming molding of the midsole and the integrated molding of the midsole and outsole are simultaneously achieved. At the same time, the mold for molding already has the texture of the midsole and outsole, and the molded midsole and outsole are already finished soles, which only need to be cooled; there is no need for the traditional secondary molding process (first preparing a small foamed sole without texture, and then performing secondary hot pressing and cooling in a mold with texture). Therefore, the present invention saves many processes and production costs, and improves production efficiency.

[0059] The present invention provides a multifunctional sole obtained by the preparation method as described above, which is used in sports shoes. In some specific embodiments, the appearance of the sole is as follows Figure 2 As shown, the black is the rubber base, the yellow (with dots) is the lower midsole, and the light gray is the upper midsole. The sole functions include: the upper midsole: ultra-soft and extremely elastic; the lower midsole: high support and compression resistance; the rubber outsole: wear-resistant and anti-slip.

[0060] Some embodiments of the present invention obtain an integrally formed two-color multifunctional midsole and outsole. First, it breaks through the limitations of the existing single-function foamed soles and monochrome appearance, and can meet consumers' multi-faceted demands for foamed sole performance and personalized appearance; secondly, the formulas of the upper midsole, lower midsole and outsole, as well as the hot-melt adhesive film, etc. all use polymers with high compatibility and strong polarity, which improves the polarity and compatibility of each layer of the sole structure, which is beneficial to enhancing the adhesion between different layers and improving the bonding strength; finally, the two-color sole foaming cross-linking and rubber raw rubber vulcanization are integrally formed, which simplifies the production process, reduces production costs, and improves the production environment, avoiding the pollution of glue and paint to the environment and the harm to the health of employees, which is a first in the industry. BRIEF DESCRIPTION OF THE DRAWINGS

[0061] Figure 1 Schematic diagram of the molding process of the shoe sole in an embodiment of the present invention;

[0062] Figure 2 These are photos of shoe sole samples in some embodiments. DETAILED DESCRIPTION

[0063] In order to have a clearer understanding of the technical features, purposes and effects of the present invention, the technical scheme of the present invention is now described in detail below in conjunction with specific embodiments. The described embodiments are only a part of the embodiments of the present invention, rather than all of the embodiments.

[0064] In order to further understand the present invention, the present invention is described in detail below in conjunction with the examples, and the protection scope of the present invention is not limited by the following examples. Unless otherwise specified, all the weight ratios in the present invention are weight ratios. In addition, the experimental methods without specifying the specific experimental conditions are conventional methods and conditions known in the art.

[0065] Examples 1-5

[0066] (1) Implementation steps of midsole blank

[0067] Weighing materials: According to the dosage of the formula in Table 1, weigh BIBP and foaming agent as the first group; weigh stearic acid, zinc stearate, zinc oxide, color particles, and filler as the second group; weigh the remaining materials as the third group.

[0068] Mixing: First, pour the third group of materials into the internal mixer and turn on the machine. When the temperature rises to 80-85℃, pour in the second group of materials; when the temperature rises to 90-95℃, pour in the third group of materials; when the temperature rises to 100-110℃, pour out the mixed materials.

[0069] Material making: Pour the mixed material into the material making machine, adjust the temperatures of the first, second, third, fourth and fifth zones to 75, 80, 85, 90 and 92°C respectively, adjust the screw speed to 40-50 rpm, and adjust the cutting speed to 15-20 rpm.

[0070] IP injection two-color rough blank: Pour the finished pellets into the two-color IP injection machine, and adjust the temperature of the first, second, third and fourth feeding zones to 84-86-88-90℃ respectively; the injection speed is 50(±2)-45(±2)-40(±2)-35(±2)-30(±2)%; the injection pressure is 90(±5)-90(±5)-90(±5)-90(±5)-90(±5)bar; the vacuum time is 80±20 seconds; the upper and lower mold temperatures of the molding mold are adjusted to 175±5℃ and 175±5℃ respectively. The injection material amount is 100±20g, the injection time is 150±20 seconds, and the vulcanization time is about 450. After that, take out the rough blank of the sole and cool it naturally for 2 hours to finalize.

[0071] The formulas of Examples 2-5 are shown in Table 2, and the processes are the same. In addition, a comparative example of a midsole is provided, and the process is the same as that of Example 1, and the formula is shown in Table 2.

[0072] (2) Implementation steps for laminating raw film

[0073] Weighing materials: According to the dosage of the formula in Table 3, weigh sulfur and accelerator as the first group; weigh the homogenizer, silane coupling agent, zinc oxide, stearic acid, antioxidant, antifogging agent, microcrystalline wax, antioxidant and other compounding agents as the second group; weigh the maleic anhydride modified white carbon black as the third group; and weigh the remaining rubber materials as the fourth group. Table 3 contains the rubber material formulas of Examples 1-5, and also includes the rubber material formulas of the comparative examples.

[0074] Mixing and sheeting: Pour the fourth group of rubber materials into the internal mixer, start the internal mixer, mix for 10 minutes, then pour in the third group of materials, mix for 12 minutes to fully mix the rubber and modified silica, and pour out the mixed mixture when the temperature of the internal mixer rises to 110°C. Put the mixed rubber into the open mixer, roll it continuously for 5-10 times, and make it into a 10mm thick sheet, park it for 4-8 hours, and stand by. Pour the mixed rubber after parking for 5 hours into the internal mixer again, and pour the third group of materials into the internal mixer together, mix for 8 minutes, and pour out the mixed rubber when the temperature of the internal mixer rises to 110°C. Pour the mixed rubber into the open mixer, roll it continuously for 5-8 times, add accelerator TS and crosslinking agent sulfur, and make it into a 2-3mm thick sheet.

[0075] Cutting: Cut the 2-3mm thick sheet into the size required by the large bottom mold.

[0076] Lamination: Cut the EVA hot melt adhesive film into the same shape and size as the rubber sheet, and cover it on the top surface of the cut rubber sheet, then put it into the flat-bed molding vulcanizer, press down the upper mold cover, close the mold, set the temperature to 50-60℃ and press for 20-30 seconds, then open the upper mold cover, and then tear off the protective layer PET film of the EVA hot melt adhesive film to obtain a coated rubber raw rubber sheet. The bottom surface of the raw rubber sheet contacts the lower mold, and the top surface of the raw rubber sheet is covered with a hot melt adhesive film. The EVA hot melt adhesive film contains 90% EVA, 5% maleic anhydride and 5% methacrylic acid, and is a composite hot melt adhesive film.

[0077] (3) One-piece molded sole finished product

[0078] Molding foaming / vulcanization integrated molding: Place the cooled two-color midsole rough blank on the top surface of the hot melt adhesive film, that is, the hot melt adhesive film is on the top surface of the outsole and on the bottom surface of the midsole; press down the upper mold cover of the flat-plate molding vulcanizer, close the mold, and complete the integrated molding. The hot pressing temperature is: 170±5℃; the hot pressing time is: 600±30 seconds.

[0079] Cooling: Pull out the molded sole and transfer it to the cooling station. Set the cooling water temperature to 23-28℃ and the cooling time to 420±30 seconds. After cooling, take out the finished product of the two-color multifunctional sole.

[0080] Table 1: Formula for preparing midsole mold blank in Example (parts by weight)

[0081]

[0082]

[0083] According to the test standards, for the one-piece molded sample, cut out the upper or lower layer blocks for separate testing.

[0084] Table 2 Comparative Example Preparation of Midsole Parison Formula (parts by weight)

[0085]

[0086]

[0087] Table 3 Example of the preparation of raw film formula (weight parts)

[0088]

[0089]

[0090] Rubber sheets are vulcanized individually and tested according to standard specifications to determine their performance formula.

[0091] The specific contents of the above raw materials are as follows:

[0092] EVA 33121: hardness 63A, VA content 33%, crystallinity 14.5%, DuPont.

[0093] EBA 3427: Hardness 89A, acrylate content 27%, crystallinity 27%, DuPont.

[0094] POE 8180: hardness 63A, crystallinity 16%, Dow.

[0095] SEBS P1083: styrene content 20%, hardness 56A, Asahi Kasei Corporation.

[0096] Fusabond A560: Maleic anhydride content 1%, hardness 82A, DuPont.

[0097] EVA 7350: hardness 88A, VA content 18%, crystallinity 36.5%, Formosa Plastics Corporation.

[0098] Fusabond 514D: methacrylic acid content 9%, hardness 53D, crystallinity 50%, DuPont.

[0099] OBC 9107: melting point 121°C, hardness 60A, crystallinity 10.6%, Dow Chemical.

[0100] EPDM 5565: ethylene content 50%, ENB content 7.5%, crystallinity 1%, Mooney viscosity 65 (ML1+4@100℃), Dow.

[0101] BR CB22: Mooney viscosity 63±3 (ML1+4@100℃), LANXESS.

[0102] NR SVR-3L: Mooney viscosity 80±20 (ML1+4@100℃), Vietnamese standard rubber.

[0103] BIIR X2: Mooney viscosity 32±3 (ML1+4@100℃), LANXESS.

[0104] ACM-2212: Mooney viscosity 40±5 (ML1+4@100℃), Dewey Rubber Technology Co., Ltd.

[0105] Maleic anhydride modified silica: BET specific surface area 180m 2 / g, Evonik AG.

[0106] Ordinary white carbon black: BET specific surface area 180m 2 / g, Degussa Corporation.

[0107] S-80: Rubber masterbatch made of 80% sulfur + 20% EPDM rubber, Dongguan Owen New Materials Co., Ltd.

[0108] Microcrystalline paraffin: RW-160, C26-C28, protection temperature 20-30℃, Lianyungang Ruiba Chemical Co., Ltd.

[0109] Anti-fog agent: HB-1956, Guangdong Duba New Material Technology Co., Ltd.

[0110] Silane coupling agent: A-172, Huaxiang Chemical Trading Co., Ltd.

[0111] The test was conducted according to the test method of [GB / T 21396-2008], and the bonding performance of the midsole / outsole after one-piece molding is as follows:

[0112] Table 4 Adhesion strength test results

[0113]

[0114] Analysis: From the test data of Examples 1-4 of the midsole, it can be seen that the upper midsole achieves ultra-soft and extremely high elasticity, and the lower midsole achieves high support and compression resistance. Moreover, the ethylene-vinyl acetate polymer, ethylene-butyl acrylate polymer, ethylene-methacrylic acid polymer, and ethylene-butyl acrylate-maleic anhydride copolymer added to the two-layer formula of the midsole are all ethylene-ester / acid polymers with strong polarity and high compatibility, which is conducive to enhancing the interfacial force of the two-layer midsole. By adjusting the content of ethylene-butyl acrylate-maleic anhydride copolymer Fusabond A560 to 5-10 parts, excellent bonding strength can be achieved. The higher the content of Fusabond A560, the stronger the bonding strength.

[0115] From the test data of Example 5 of the midsole, it can be seen that by setting different foaming ratios for the upper midsole and the lower midsole, a two-color midsole with good performance and excellent bonding strength can be obtained, which illustrates the feasibility of the process of one-piece injection molding of a two-color midsole.

[0116] From the test data of Comparative Examples 1-3 of the midsole, it can be seen that without adding ethylene-butyl acrylate-maleic anhydride copolymer Fusabond A560, whether it is not added to the upper layer, the lower layer, or both the upper and lower layers, the bonding strength of the two layers of the midsole will decrease, especially when neither the upper and lower layers are added, the bonding strength decreases significantly. This shows that Fusabond A560 not only has a strong polarity, which is conducive to improving the interfacial bonding strength of the upper and lower midsole layers, but also the ethylene-butyl acrylate structure therein can efficiently connect other components in the two-layer midsole formula, improving compatibility and intermolecular forces.

[0117] From the test data of Comparative Examples 4-5 of the midsole, it can be seen that not adding ethylene-butyl acrylate-maleic anhydride copolymer Fusabond A560, not adding ethylene-butyl acrylate polymer or ethylene-methacrylic acid polymer will also lead to weakened polarity of the midsole and reduced bonding strength, but the impact is less.

[0118] In addition, according to the formulas in Tables 1 / 2 / 3, after the materials were prepared respectively, they were integrally molded according to different embodiments / comparative examples of midsole + outsole combinations. The sample performance test results are shown in Table 5. The test only tests the bonding strength between the midsole and the lower outsole (this test is a conventional test for the sole).

[0119] Table 5 Adhesion strength test results of samples of the present invention

[0120]

[0121]

[0122] From the test data of midsole embodiments 1, 2, 3, 5 and outsole embodiments 1-5 / comparative examples 1-4, it can be seen that: ① As the content of polyacrylate rubber in the outsole increases, the bonding strength between the lower layer of the midsole and the outsole shows an upward trend; when the content of polyacrylate rubber is 10 parts, the bonding strength drops to about 18N / cm, which is lower than the industry bonding strength standard, so the polyacrylate rubber content is preferably 15-25 parts. When the polyacrylate rubber content is 0, the bonding strength drops significantly. ② As the amount of maleic anhydride modified fumed silica added to the outsole increases, the bonding strength increases slightly, and is better than the bonding strength when ordinary silica is added, indicating that maleic anhydride modified fumed silica has a higher polarity, which is beneficial to improving the polarity of the rubber outsole and the bonding strength with the hot melt adhesive film. Similarly, from the test data of midsole embodiments 2, 3, 5 and outsole embodiments 1-5 / comparative examples 1-4, it can be seen that the above variation trend can also be obtained, which illustrates the feasibility of adding polyacrylate rubber and maleic anhydride modified fumed silica.

[0123] From the test data of midsole examples 1, 2, 3, 5 / comparative example 1 and outsole example 1, it can be seen that as the content of ethylene-butyl acrylate-maleic anhydride copolymer Fusabond A560 in the lower layer of the midsole is higher, the bonding strength between the lower layer of the midsole and the rubber outsole is higher. If ethylene-butyl acrylate-maleic anhydride copolymer is not added to the lower layer of the midsole, the bonding strength is reduced to less than 20N / cm, which does not meet the industry standard. This shows the technical feasibility of using ethylene-butyl acrylate-maleic anhydride copolymer in the present invention. Similarly, from the test data of midsole examples 1, 2, 3, 5 / comparative example 1 and outsole example 2, or with example 3, or with example 4, or with example 5, or with comparative example 1, or with comparative example 2, or with comparative example 3, or with comparative example 4, the above trend can be obtained; this shows the technical feasibility of using ethylene-butyl acrylate-maleic anhydride copolymer in the present invention.

[0124] From the test data of midsole comparative example 4 and outsole examples 1-5 / comparative examples 1-4, it can be seen that not adding ethylene-methacrylic acid polymer to the midsole lower layer formula will weaken the polarity of the formula and the bonding strength of the midsole and outsole will decrease slightly.

[0125] As can be seen from the above embodiments, the upper layer of the midsole of the present invention is mainly super soft and extremely elastic, and the formula uses ethylene-vinyl acetate polymer, ethylene-butyl acrylate polymer, polyolefin random polymer, styrene-butadiene-styrene block copolymer, ethylene-butyl acrylate-maleic anhydride copolymer and other matrices; the lower layer of the midsole is mainly high support and compression resistance, and the formula uses ethylene-vinyl acetate polymer, ethylene-methacrylic acid polymer, ethylene-butyl acrylate-maleic anhydride copolymer, polyolefin block copolymer, ethylene-propylene terpolymer and other matrices; the rubber outsole is mainly wear-resistant and non-slip, and the formula uses rare earth butadiene rubber, natural rubber, polyacrylate rubber, brominated butyl rubber and other matrices. The formula of the three-layer structure of the embodiment of the present invention contains polar polymers, such as ethylene-vinyl acetate polymer, ethylene-butyl acrylate polymer, ethylene-methacrylic acid polymer, ethylene-butyl acrylate-maleic anhydride copolymer added in the two-layer formula of the midsole, which are all ethylene-ester / acid polymers, which are conducive to enhancing the interface force of the two-layer midsole. In addition, the polyacrylate rubber (ACM rubber) in the rubber outsole not only improves polarity, but also enhances compatibility with the EVA hot melt adhesive film, thereby improving bonding strength. The hot melt adhesive film is based on EVA, which can achieve excellent compatibility and interface force not only with the rubber outsole but also with the midsole, thereby improving the bonding strength between the three. The two layers of the midsole and the rubber outsole are also matched with other polymers to achieve different functions such as softness, high elasticity, support and pressure resistance.

[0126] At the same time, the upper and lower midsole formula materials described in the embodiment of the present invention are first ejected into a molded blank using a two-color injection machine at one time, the outsole rubber is a raw rubber sheet that has not been vulcanized after mixing, and the top surface of the raw rubber sheet is covered with an EVA hot melt adhesive film. The two-color midsole molded blank and the coated raw rubber sheet are molded in a mold, wherein the two layers of the midsole are foamed and cross-linked at high temperature, and the rubber raw rubber sheet is vulcanized and cross-linked at the same temperature, and the integrated foaming molding of the midsole and the integrated molding of the mid and outsole are simultaneously realized during the foaming and cross-linking and vulcanization and cross-linking processes. In addition, the molding mold already has the texture of the midsole and outsole, and after molding, it is cooled to obtain a finished sole with good performance. The present invention saves many processes and production costs and improves production efficiency.

[0127] Compared with the existing one-piece molded sole or two-color sole, the one-piece molded two-color multifunctional midsole and outsole of the embodiment of the present invention can meet the consumers' various demands for the performance of the foamed sole and the personalized demands for the appearance. The upper layer, the lower layer and the outsole of the midsole are all made of polymers with good compatibility and strong polarity, which improves the polarity and compatibility of the sole components of each layer, is conducive to enhancing the adhesion between different layers, improving the bonding strength, and preventing the undesirable problems such as debonding in the later stage. Compared with the traditional two-color effect by spraying or combining, and the process that the midsole and the outsole need to be glued, the one-shot two-color appearance midsole of the embodiment of the present invention greatly simplifies the production process, reduces the production cost, and improves the production environment, etc., because the two-color midsole foaming and rubber raw rubber vulcanization are integrated and molded.

[0128] The above examples are only used to illustrate the technical features and implementation process of the present invention, rather than to limit the technical solution of the present invention. It should be pointed out that for ordinary technicians in this field, the present invention can still be modified or replaced by equivalents, and modifications or replacements that do not deviate from the principles of the present invention are all covered by the protection of the present invention.

Claims

1. A method for preparing an integrally formed multifunctional sole, characterized in that: The following steps are involved: The first midsole material and the second midsole material are injected once by a two-color injection device to obtain a midsole blank; the first midsole material uses ethylene-vinyl acetate copolymer, ethylene-butyl acrylate copolymer, random polyolefin, styrene-butadiene-styrene block copolymer and ethylene-butyl acrylate-maleic anhydride copolymer as the base resin; the second midsole material uses ethylene-vinyl acetate copolymer, ethylene-methacrylic acid copolymer, ethylene-butyl acrylate-maleic anhydride copolymer, block polyolefin and ethylene-propylene terpolymer as the base resin; The midsole mold and the coated raw rubber sheet are molded and pressed in a mold, so that the midsole mold is foamed and cross-linked at a high temperature, and the raw rubber sheet is vulcanized and cross-linked at the same temperature, so as to obtain an integrally molded multifunctional sole; The coated raw rubber sheet includes: a mixed rubber sheet mainly composed of rare earth butadiene rubber, natural rubber, polyacrylate rubber and brominated butyl rubber, and an EVA hot melt adhesive film covering the top surface thereof, wherein the EVA hot melt adhesive film contacts the second midsole material injection structure of the midsole blank.

2. The preparation method according to claim 1, characterized in that: In parts by weight, the first midsole material includes: 40-50 parts of ethylene-vinyl acetate copolymer, 10-20 parts of ethylene-butyl acrylate copolymer, 15-25 parts of random polyolefin, 10-15 parts of styrene-butadiene-styrene block copolymer, 5-10 parts of ethylene-butyl acrylate-maleic anhydride copolymer, 0.5-0.6 parts of peroxide crosslinking agent, 3-4 parts of foaming agent, 1.2-1.5 parts of stearic acid, 1.0-1.5 parts of zinc stearate, 0.8-1.2 parts of zinc oxide, 2-3 parts of filler and 0.5-2 parts of color particles.

3. The preparation method according to claim 2, characterized in that: In parts by weight, the second midsole material includes: 40-50 parts of ethylene-vinyl acetate copolymer, 10-25 parts of ethylene-methacrylic acid copolymer, 5-10 parts of ethylene-butyl acrylate-maleic anhydride copolymer, 15-25 parts of block polyolefin, 10-15 parts of ethylene-propylene terpolymer, 0.5-0.6 parts of peroxide crosslinking agent, 3-4 parts of foaming agent, 1.2-1.5 parts of stearic acid, 1.0-1.5 parts of zinc stearate, 0.8-1.2 parts of zinc oxide, 2-3 parts of filler and 0.5-2 parts of color particles.

4. The preparation method according to claim 3, characterized in that: In the first midsole material, the VA content of the ethylene-vinyl acetate copolymer is 25-40%; the butyl acrylate content of the ethylene-butyl acrylate copolymer is 25-30%; and the hardness of the random polyolefin is 50-65A; In the second midsole material, the VA content of the ethylene-vinyl acetate copolymer is 15-24%; the methacrylate content of the ethylene-methacrylate copolymer is 5-15%; and the melting point of the block polyolefin is above 120°C.

5. The preparation method according to claim 4, characterized in that: The molding mold temperature of the two-color injection equipment is 170-180° C., and the cross-linking time of one shot is 420-480 seconds, followed by natural cooling and shaping.

6. The preparation method according to claim 1, characterized in that: The materials of the mixed rubber sheet include, by weight: 40-50 parts of rare earth butadiene rubber, 15-25 parts of natural rubber, 15-25 parts of polyacrylate rubber, 10-20 parts of brominated butyl rubber, 40-50 parts of maleic anhydride modified fumed silica, 3-5 parts of processing oil, 2-3 parts of sulfur, 1-2 parts of homogenizer, 2-4 parts of silane coupling agent, 2-3 parts of zinc oxide, 1.0-1.2 parts of stearic acid, 0.8-1.0 parts of antioxidant, 1-1.2 parts of antifogging agent, 0.8-1 parts of microcrystalline wax, 0.3-0.5 parts of antioxidant, 0.9-1.1 parts of accelerator DM, 0.4-0.6 parts of accelerator D and 0.05-0.06 parts of accelerator TS.

7. The preparation method according to claim 6, characterized in that: In the materials of the mixed rubber sheet, the cis-1,4-butadiene content of the rare earth cis-1,4-butadiene rubber is more than 98%; the Mooney viscosity ML1+4@100°C of the brominated butyl rubber is 29-35; the Mooney viscosity ML1+4@100°C of the polyacrylate rubber is 35-45; the maleic anhydride ratio of the maleic anhydride modified fumed silica is 2-3%, and the BET specific surface area is greater than 170m 2 / g.

8. The preparation method according to any one of claims 1 to 7, characterized in that: The EVA hot melt adhesive film contains 90-98% of EVA, 1-5% of maleic anhydride and 1-5% of methacrylic acid.

9. The preparation method according to claim 8, characterized in that: The molding temperature is 165-175° C., the time is 570-630 seconds, and then cooling is performed to obtain an integrally molded multifunctional sole.

10. The multifunctional sole obtained by the preparation method according to any one of claims 1 to 9 is used in sports shoes.

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