Preparation method of shoe sole stable in bonding and prepared shoe sole

Abstract

The invention relates to the field of shoe sole processing, in particular to a preparation method of a shoe sole stable in bonding and the shoe sole prepared through the preparation method. Comprising the following steps: pre-vulcanizing and shaping an unvulcanized and viscous rubber material to obtain an incompletely vulcanized and crosslinked viscous outsole blank; the midsole and the outsole blank are attached, heated and vulcanized, so that the midsole and the outsole blank are completely vulcanized and crosslinked, and the sole is obtained; the unvulcanized viscous rubber material is composed of a rubber compound, a tackifier and a vulcanizing agent. By means of the mode that the incompletely vulcanized and crosslinked viscous outsole blank and the insole are attached and then completely vulcanized, the problem of uneven coating or bubbles possibly occurring in the traditional hot melt adhesive bonding process is solved, and the attaching stability and the bonding quality of the shoe sole are remarkably improved.

Description

Technical Field

[0001] The present application relates to the field of sole processing. More specifically, it relates to a preparation method for a sole with stable adhesion and the obtained sole. Background Art

[0002] Shoemaking technologies have made remarkable progress in recent years, especially in improving comfort, durability, and appearance design. With the growing demand for high-quality footwear products from consumers, manufacturers are constantly exploring new production processes and technical means to optimize product quality. In the modern shoemaking industry, as one of the key components, the structure and material selection of the sole directly affect the overall performance of the shoes and the user experience. To achieve better fitting effects and extend service life, the industry has been continuously committed to developing more efficient sole preparation processes.

[0003] Currently, in the actual production process, in order to firmly bond the outsole and the midsole, common methods include but are not limited to hot melt adhesive bonding, hot press molding, and cold adhesion processes, etc. Among them, the hot melt adhesive bonding method melts the hot melt adhesive by heating and coats it between two layers of materials to complete the adhesion; the hot press molding method promotes a tight combination between materials by means of a high-temperature and high-pressure environment; while the cold adhesion process is to use chemical reagents with strong adhesion at room temperature for connection operations. These traditional methods have their own characteristics and have been widely used for many years, constituting the current mainstream sole assembly technology framework.

[0004] However, the above-mentioned conventional methods generally have some problems that are difficult to overcome, especially when facing designs with complex shapes or specific functional requirements, which are more prominent. For example, during the bonding process using hot melt adhesives or other similar substances, there are often problems such as uneven coating distribution or internal air bubbles, which directly lead to a decrease in the stability and reliability of the final product. In addition, when it comes to outdoor shoes, work shoes, or other special styles of products, or during mass production, the fitting process is more likely to have blistering phenomena, thereby reducing the tightness of the sole structure and the durability during long-term use. Summary of the Invention

[0005] In order to improve processing efficiency and fitting stability and ensure the durability of the sole, a sole with stable adhesion and its preparation method are provided.

[0006] In a first aspect, the present application provides a preparation method for a sole with stable adhesion, including the following steps: Pre-vulcanize and shape the unvulcanized and sticky rubber compound to obtain an outsole embryo that is not fully vulcanized and cross-linked and has stickiness; then fit the midsole with the outsole embryo and heat vulcanize it to make it fully vulcanized and cross-linked to obtain the sole; The unvulcanized and sticky rubber compound is composed of a mixed rubber, a tackifier, and a vulcanizing agent.

[0007] By adopting the above technical solution, the bonding of the outsole and the midsole can be completed without using hot melt adhesive or hot melt adhesive film, simplifying the production process flow and improving the processing efficiency. The uncured and sticky rubber compound is used for pre-vulcanization and shaping to form the outsole embryo, and complete vulcanization cross-linking is achieved during the subsequent heating and vulcanization process, effectively avoiding problems such as bubbles and uneven coating that may occur in the traditional hot melt method, and improving the overall bonding stability and bonding strength of the sole. In addition, this method is particularly suitable for sole structures with irregular surfaces and can significantly improve the manufacturing quality of special styles of shoes such as outdoor shoes and work shoes.

[0008] The compounded rubber is a non-crosslinked and flowable rubber compound in which compounding agents are mixed in block, granular and powdered raw rubber. The tackifier can increase adhesion, and the vulcanizing agent plays a vulcanizing role. Therefore, when the compounded rubber, tackifier and vulcanizing agent are mixed evenly, the obtained rubber compound has the characteristics of being uncured and sticky, so that the uncured and sticky rubber compound can be stabilized.

[0009] Preferably, the temperature of the pre-vulcanization and shaping is 70-80 °C and the time is 1-3 min; the heating and vulcanization are divided into two stages: the first stage has a temperature of 150-165 °C and a vulcanization time of 5-10 min; the second stage has a temperature of 90-98 °C, a time of 20-30 min, and a pressure of 5-10 MPa.

[0010] By adopting the above technical solution, the temperature of the pre-vulcanization and shaping is set at 70-80 °C and the time is controlled within 1-3 min, which can effectively form an outsole embryo that is not fully vulcanized and cross-linked and has stickiness, ensuring the initial stability when it is bonded to the midsole. Subsequently, during the heating and vulcanization process, through the settings of temperature and time, complete vulcanization cross-linking of the outsole and the midsole can be achieved, further improving the connection strength and bonding stability between the two. This solution not only simplifies the complex process of traditional hot melt adhesive bonding, but also avoids problems such as bubble generation, and is particularly suitable for the preparation of soles with irregular surfaces, significantly improving the overall bonding stability and structural reliability of the sole.

[0011] Preferably, the compounded rubber is one or more of silicone rubber compounded rubber, natural rubber compounded rubber, and synthetic rubber compounded rubber.

[0012] By adopting the above technical solution, selecting one or more of silicone rubber compound, natural rubber compound or synthetic rubber compound as the compound can endow the unvulcanized and sticky rubber compound with better fluidity and elastic properties. Specifically, the silicone rubber compound improves the wear resistance, oil resistance and environmental adaptability of the sole; the natural rubber compound enhances the elasticity and grip of the sole; and the synthetic rubber compound provides diverse performance options and good processing economy. These advantages work together to make the prepared outsole embryo more stable when bonded to the midsole, improving the overall structural stability and bonding quality of the final sole.

[0013] Preferably, the tackifier is an EMH powder-carboxyl-terminated polycaprolactone blend dispersion.

[0014] By adopting the above technical solution, using the EMH powder-carboxyl-terminated polycaprolactone blend dispersion as the tackifier can significantly improve the adhesion performance of the unvulcanized and sticky rubber compound. Specifically, the components in this tackifier act synergistically to effectively enhance the bonding force between the rubber compound and the midsole, promote the stable bonding of the outsole and the midsole, thereby improving the overall structural stability of the sole and avoiding the bubbles and unevenness that may occur in the traditional hot melt adhesive bonding process. At the same time, this tackifier also has good cross-linking performance, further improving the mechanical properties and durability of the sole during the subsequent heat vulcanization process.

[0015] Preferably, the EMH powder-carboxyl-terminated polycaprolactone blend dispersion is composed of the following raw materials in weight percentages: 30-50% of EMH powder 20-30% of bis-3-methacryloxypropyltetramethyldisiloxane 1-3% of polyethylene glycol-polydimethylsiloxane-polyethylene glycol 2-5% of methyl vinyl ether-maleic anhydride copolymer The balance is liquid carboxyl-terminated polycaprolactone.

[0016] By adopting the above technical solutions, the EMH powder can improve compatibility, adhesion and wear resistance in the tackifier system; bis-3-methacryloxypropyltetramethyldisiloxane can improve the crosslinking effect and enhance the bonding strength between the silicone rubber sole and other materials through chemical reaction with rubber; polyethylene glycol-polydimethylsiloxane-polyethylene glycol and methyl vinyl ether-maleic anhydride copolymer synergistically promote dispersion and improve the dispersion uniformity of the entire rubber compound system; the active groups contained in liquid carboxyl-terminated polycaprolactone can further promote the crosslinking density in the rubber material and improve the wear resistance of the sole. These components act synergistically with each other, enabling the prepared EMH powder-carboxyl-terminated polycaprolactone blend dispersion to have excellent tackifying effect, thereby enhancing the adhesion stability and structural stability between the unvulcanized and sticky outsole and the midsole, and effectively avoiding the phenomenon of detachment during use.

[0017] In this application, the use of EMH powder, bis-3-methacryloxypropyltetramethyldisiloxane, polyethylene glycol-polydimethylsiloxane-polyethylene glycol, methyl vinyl ether-maleic anhydride copolymer, and liquid carboxyl-terminated polycaprolactone can play a synergistic role, further improving the tackifying effect of the tackifier, enabling the unvulcanized and sticky outsole after pre-vulcanization and shaping to have better adhesion stability and structural stability. When it is bonded to the midsole, it is fully vulcanized and crosslinked, making the obtained sole have better structural stability and avoiding the possibility of detachment during use. In addition, by using the tackifier obtained in this application and then applying it to the rubber compound, it can play a better adhesion role to the midsoles of various materials, thereby improving the overall structural stability of the sole.

[0018] Preferably, the EMH powder-carboxyl-terminated polycaprolactone blend dispersion is prepared by the following method: Weigh polyethylene glycol-polydimethylsiloxane-polyethylene glycol, methyl vinyl ether-maleic anhydride copolymer, and EMH powder according to weight percentage, mix them evenly, and then add liquid carboxyl-terminated polycaprolactone and bis-3-methacryloxypropyltetramethyldisiloxane, and mix them evenly to obtain the EMH powder-carboxyl-terminated polycaprolactone blend dispersion.

[0019] By adopting the above technical solutions, polyethylene glycol-polydimethylsiloxane-polyethylene glycol and methyl vinyl ether-maleic anhydride copolymer synergistically promote the dispersibility of EMH powder in the tackifier system and improve the dispersion uniformity of the rubber compound system. Bis-3-methacryloxypropyltetramethyldisiloxane enhances the bonding strength between the silicone rubber sole and other materials through chemical reaction and improves the crosslinking effect. The active groups provided by liquid carboxyl-terminated polycaprolactone can further increase the crosslinking density and wear resistance of the rubber material. These components act together, significantly improving the tackifying effect of the tackifier, enhancing the adhesion stability and overall structural stability between the outsole and the midsole, and effectively preventing the phenomenon of detachment during use.

[0020] Preferably, it also includes preheating the bottom surface of the midsole at a temperature of 100 - 110 °C for 1 - 2 minutes.

[0021] By adopting the above technical solution, preheating the bottom surface of the midsole can improve the thermal bonding effect between the midsole and the outsole blank during the subsequent bonding process. Specifically, preheating for 1 - 2 minutes at a temperature of 100 - 110 °C can make the surface of the midsole reach an appropriate state, thereby enhancing the contact adaptability with the outsole blank that is not fully vulcanized and crosslinked and has adhesiveness, and reducing the voids or poor contact areas between the interfaces. This measure helps to further improve the overall bonding stability of the sole, especially when facing the connection parts of the outsole and midsole with complex or irregular shapes, effectively avoiding quality problems caused by poor bonding.

[0022] Preferably, the midsole contains an EMH powder - carboxyl - terminated polycaprolactone blend dispersion.

[0023] By adopting the above technical solution, the midsole contains an EMH powder - carboxyl - terminated polycaprolactone blend dispersion, which can improve the performance of the midsole itself and enhance the connection stability between the midsole and the outsole. Specifically, the components in the EMH powder - carboxyl - terminated polycaprolactone blend dispersion act synergistically to improve the adhesiveness, abrasion resistance and structural stability of the midsole material, so that the overall bonding effect of the sole is better, and problems such as detachment or cracking during use can be avoided.

[0024] The material of the midsole usually adopts EVA, PU, rubber, TPR, PVC, TR, TPEE, etc. Adding an EMH powder - carboxyl - terminated polycaprolactone blend dispersion to the above materials can not only improve their performance, but also improve the connection stability between the midsole and the outsole, and improve their comprehensive performance.

[0025] Preferably, the unvulcanized and adhesive rubber compound is prepared by the following method: Weigh the mixing rubber compound according to parts by weight, roll it, heat it to 100 - 120 °C, add an EMH powder - carboxyl - terminated polycaprolactone blend dispersion, mix it evenly, then cool it down to 35 - 45 °C, add a vulcanizing agent, and mix it evenly to obtain the unvulcanized and adhesive rubber compound.

[0026] By adopting the above technical scheme, the preparation method of unvulcanized and sticky rubber compound can achieve the following effects: first, by rolling the mixed rubber and heating it within a specific temperature range, it is helpful to fully soften the mixed rubber, improve its fluidity and the mixing uniformity of subsequent components; second, add EMH powder-carboxyl-terminated polycaprolactone blended dispersion under heating conditions, and the various components in the dispersion can give full play to the effects of viscosity increase, cross-linking promotion and compatibility improvement, so that the rubber compound has a strong adhesion ability; third, add the vulcanizing agent after cooling and mix evenly. This operation avoids the problem of local premature cross-linking caused by premature addition of the vulcanizing agent, ensuring that the final rubber compound has neither early vulcanization nor good viscosity. The unvulcanized and sticky rubber compound thus obtained is not only convenient for subsequent pre-vulcanization shaping and midsole fitting operations, but also effectively improves the overall bonding stability and structural reliability of the sole.

[0027] In a second aspect, a bonding-stable sole comprises a midsole and an outsole, wherein the midsole is fixedly connected to the outsole, and the sole is obtained by a method for preparing a bonding-stable sole.

[0028] By adopting the above technical scheme, the unvulcanized and sticky rubber compound is pre-vulcanized to form a large sole embryo, and then bonded to the midsole and heated and vulcanized to completely cross-link, which effectively improves the bonding stability and structural reliability of the sole. This method eliminates the complicated operation process of traditional hot melt adhesive or hot melt adhesive film, avoids the problems caused by uneven coating or bubbles, is particularly suitable for the preparation of soles with irregular surfaces, and improves the overall processing efficiency and product quality. According to different implementation methods, by optimizing the specific parameters of pre-vulcanization and heated vulcanization, selecting a specific type of mixed rubber, adding EMH powder-carboxyl-terminated polycaprolactone blended dispersion and its component formula, the performance of the sole is further enhanced, ensuring a firm connection between the large sole and the midsole, while giving the sole excellent wear resistance, elasticity and environmental protection characteristics. Improvement measures such as preheating of the midsole and adding tackifiers to the midsole material also help to strengthen the fit tightness and stability of the two, and finally obtain a sole product with high structural stability and long service life.

[0029] In summary, the present application includes at least one of the following beneficial technical effects: 1. By using the method of laminating the incompletely vulcanized and cross-linked but sticky outsole with the midsole and then fully vulcanizing it, the problem of uneven coating or bubbles that may occur in the traditional hot melt adhesive bonding process is avoided, and the lamination stability and bonding quality of the sole are significantly improved; 2. The outsole embryo is prepared using a rubber compound containing a rubber compound, a tackifier and a vulcanizer, which not only simplifies the processing flow, but also ensures that the outsole has good adhesion performance in the pre-vulcanization stage, thereby improving the overall production efficiency and reliability; 3. It is particularly suitable for the connection between the outsole and the midsole with irregular surfaces, such as special styles like outdoor shoes or work shoes. It can achieve a better fitting effect under complex structures, meet diverse design requirements, and enhance the durability of the sole at the same time. Detailed implementation manners

[0030] The present application will be further described in detail below with reference to the embodiments.

[0031] The silicone rubber masterbatch uses Dow (Dow Corning) RBB - 2881 series with a hardness of 50A; The EMH powder is a terpolymer, namely ethylene - acrylate - maleic anhydride copolymer, with a number - average molecular weight of 20,000; The poly(ethylene glycol) in poly(ethylene glycol) - poly(dimethylsiloxane) - poly(ethylene glycol) has a viscosity - average molecular weight of 200 - 400, and the poly(dimethylsiloxane) has a viscosity - average molecular weight of 1000 - 2000; The chemical formula of the methyl vinyl ether - maleic anhydride copolymer: (C4H2O3)n.(C3H6O)n, where n is 10 - 20; The liquid carboxyl - terminated polycaprolactone is OH - PCL - COOH, with a viscosity - average molecular weight of 1000 - 2000.

[0032] Preparation example of the EMH powder - carboxyl - terminated polycaprolactone blend dispersion Preparation example 1 An EMH powder - carboxyl - terminated polycaprolactone blend dispersion is prepared by the following method: By weight percentage, 1% of poly(ethylene glycol) - poly(dimethylsiloxane) - poly(ethylene glycol), 5% of methyl vinyl ether - maleic anhydride copolymer, and 30% of EMH powder are weighed and mixed evenly, then 34% of liquid carboxyl - terminated polycaprolactone and 30% of bis - 3 - (methacryloyloxy)propyltetramethyldisiloxane are added and mixed evenly to obtain the EMH powder - carboxyl - terminated polycaprolactone blend dispersion.

[0033] Preparation examples 2 - 3 The differences between preparation examples 2 - 3 and preparation example 1 are: the dosages of raw materials are different, as shown in Table 1 specifically; Table 1 Raw material dosages of preparation examples 1 - 3 (%) Preparation comparative example Preparation comparative example 1 The difference between preparation comparative example 1 and preparation example 2 is: poly(ethylene glycol) - poly(dimethylsiloxane) - poly(ethylene glycol) is replaced with methyl vinyl ether - maleic anhydride copolymer in equal amount.

[0034] Preparation comparative example 2 The difference between Preparation Comparative Example 2 and Preparation Example 2 is that bis-3-methacryloxypropyltetramethyldisiloxane is replaced with liquid carboxyl-terminated polycaprolactone in equal amounts.

[0035] Preparation Comparative Example 3 The difference between Preparation Comparative Example 3 and Preparation Example 2 is that methyl vinyl ether-maleic anhydride copolymer is replaced with liquid carboxyl-terminated polycaprolactone in equal amounts.

[0036] Preparation Comparative Example 4 The difference between Preparation Comparative Example 4 and Preparation Example 2 is that bis-3-methacryloxypropyltetramethyldisiloxane, polyethylene glycol-polydimethylsiloxane-polyethylene glycol, and methyl vinyl ether-maleic anhydride copolymer are replaced with liquid carboxyl-terminated polycaprolactone in equal amounts.

[0037] Preparation Comparative Example 5 The difference between Preparation Comparative Example 5 and Preparation Example 2 is that liquid carboxyl-terminated polycaprolactone is replaced with EMH powder in equal amounts.

[0038] Preparation Comparative Example 6 The difference between Preparation Comparative Example 6 and Preparation Example 2 is that EMH powder is replaced with liquid carboxyl-terminated polycaprolactone in equal amounts. Examples

[0039] Example 1 An adhesively stable sole, comprising a midsole and an outsole, the midsole being fixedly connected to the outsole. The adhesively stable sole is prepared by the following method: Preparation of an unvulcanized and sticky rubber compound: By weight, 10 parts of a kneaded rubber compound are weighed and put into a two-roll rubber mill for rolling, heated to 100 °C, 0.5 part of a tackifier is added, and mixing is continued until uniform. Then the temperature is lowered to 40 °C, and 0.2 part of a vulcanizing agent is added, and mixing is continued until uniform to obtain an unvulcanized and sticky rubber compound. The tackifier is silane coupling agent KH550.

[0040] The unvulcanized and sticky rubber compound is put into a mold of the outsole for pre-vulcanization and shaping to obtain an incompletely vulcanized and crosslinked and sticky outsole blank. Then the midsole is bonded to the non-demolded outsole blank, with the outsole on the bottom and the midsole on the top. The mold of the outsole blank is heated to completely vulcanize and crosslink the outsole to obtain the sole.

[0041] The midsole is made of vinyl silicone rubber material, with a foaming rate of 18% and a hardness of 38A.

[0042] Among them, the temperature for pre-vulcanization and shaping is 70°C and the time is 3 min; the heating and vulcanization are divided into two stages: the first stage has a temperature of 160°C and a vulcanization time of 5 min; the second stage has a temperature of 95°C and a time of 25 min, and the laminating pressure is 8 MPa.

[0043] Example 2 The difference between Example 2 and Example 1 lies in: different process parameters, specifically as follows: The temperature for pre-vulcanization and shaping is 75°C and the time is 2 min; the heating and vulcanization are divided into two stages: the first stage has a temperature of 165°C and a vulcanization time of 6 min; the second stage has a temperature of 90°C and a time of 30 min.

[0044] Example 3 The difference between Example 3 and Example 1 lies in: different process parameters, specifically as follows: The temperature for pre-vulcanization and shaping is 80°C and the time is 1 min; the heating and vulcanization are divided into two stages: the first stage has a temperature of 150°C and a vulcanization time of 10 min; the second stage has a temperature of 98°C and a time of 30 min.

[0045] Examples 4 - 12 The difference between Examples 4 - 12 and Example 1 lies in: different sources of tackifier, as shown in Table 2 specifically; Table 2 Different sources of tackifier in Examples 4 - 12 Example 13 The difference between Example 13 and Example 1 lies in: the sole material is heat-resistant PU material.

[0046] Example 14 The difference between Example 14 and Example 1 lies in: the sole material is TPEE.

[0047] Example 15 The difference between Example 15 and Example 5 lies in: the sole material is heat-resistant PU material.

[0048] Example 16 The difference between Example 16 and Example 5 lies in: the sole material is TPEE.

[0049] Example 17 The difference between Example 17 and Example 5 lies in: preheating the bottom surface of the midsole, with a temperature of 100°C and a time of 2 min.

[0050] Example 18 Example 18 is different from Example 5 in that the bottom surface of the midsole is preheated to a temperature of 110°C for 1 minute.

[0051] Example 19 Example 19 is different from Example 18 in that the vinyl silicone rubber material of the midsole contains 2 wt% of EMH powder-carboxyl-terminated polycaprolactone blend dispersion.

[0052] Comparative Example Comparative Example 1 Comparative Example 1 is different from Example 1 in that the bonding process is different: Put the unvulcanized and sticky rubber compound into the mold of the outsole and vulcanize it at 165°C for 10 minutes to obtain a fully vulcanized and crosslinked outsole. Use a TPU hot melt adhesive film (Jinsui TPU3195) to bond the outsole and the midsole. The thickness of the hot melt adhesive film is 0.2 mm, the bonding temperature is 110°C, the bonding time is 5 minutes, and the bonding pressure is 10 MPa.

[0053] Performance Detection Test Detection Method / Test Method Test 1: For the soles obtained in Examples 1-19 and Comparative Examples 1-2, prepare samples and test the peel strength with reference to GB / T 3903.8-2022.

[0054] Test 2: For the soles obtained in Examples 1-19 and Comparative Examples 1-2, put them into a testing machine and test for 7 days at a temperature of 85°C and a humidity of 85%. After taking them out, place them at a temperature of 25°C and a humidity of 60% for 24 hours, and then detect the peel strength in the same way as in Test 1. Divide the obtained peel strength by the peel strength obtained in Test 1, and finally multiply by 100% to obtain the durability rate.

[0055] Test 3: Test the soles obtained in Examples 1-19 and Comparative Example 2 with reference to "GB / T 9867-2008 Determination of Abrasion Resistance of Vulcanized Rubber or Thermoplastic Rubber (Rotating Drum Abrasion Machine Method)". At the same time, test the midsole in Example 1 and the midsole obtained in Example 15 for rebound resilience: Test the rebound resilience with reference to GB / T 10652-2001 "Determination of Elasticity of High Polymer Porous Elastic Materials".

[0056] Table 3 Experimental Data of Examples 1-19 and Comparative Examples 1-2 Combining Example 1 and Comparative Example 1 and referring to Table 1, it can be seen that the peel strength and durability rate of Example 1 are higher than those of Comparative Example 1, indicating that the production process of the present application has better bonding stability and durability.

[0057] Combined with Example 1, Example 4, and Table 1, it can be seen that the peel strength, durability rate, and DIN wear of Example 1 and Examples 7-12 are significantly better than those of Example 4, indicating that the use of EMH powder, bis-3-methacryloxypropyltetramethyldisiloxane, polyethylene glycol-polydimethylsiloxane-polyethylene glycol, methyl vinyl ether-maleic anhydride copolymer, and liquid carboxyl-terminated polycaprolactone in this application has a synergistic effect, resulting in a sole with better comprehensive performance.

[0058] This specific embodiment is only an explanation of this application and does not limit this application. After reading this specification, those skilled in the art can make modifications to this embodiment that do not contribute creatively as needed, but as long as it is within the scope of the claims of this application, it is protected by the patent law.

Claims

1. A preparation method of a sole with stable adhesion, characterized in that, It includes the following steps: Pre-vulcanize and shape the unvulcanized and sticky rubber compound to obtain a bottom embryo that is not fully vulcanized and cross-linked and has stickiness; Then bond the midsole to the bottom embryo and heat and vulcanize it to make it fully vulcanized and cross-linked to obtain a sole; The unvulcanized and sticky rubber compound is composed of a mixed rubber, a tackifier and a vulcanizing agent.

2. The preparation method of a sole with stable adhesion according to claim 1, characterized in that: The temperature of the pre-vulcanization and shaping is 70 - 80 °C, and the time is 1 - 3 min; the heat vulcanization is divided into two stages: the first stage temperature is 150 - 165 °C, and the vulcanization time is 5 - 10 min; the second stage temperature is 90 - 98 °C, and the time is 20 - 30 min.

3. The preparation method of a sole with stable adhesion according to claim 1, wherein: The mixed rubber is one or more of silicone rubber mixed rubber, natural rubber mixed rubber, and synthetic rubber mixed rubber.

4. The preparation method of a sole with stable adhesion according to claim 1, characterized in that: The tackifier is an EMH powder-carboxyl-terminated polycaprolactone blend dispersion.

5. The preparation method of a sole with stable adhesion according to claim 1, wherein the EMH powder-carboxyl-terminated polycaprolactone blend dispersion is composed of the following raw materials in weight percentages: EMH powder 30 - 50% Bis-3-methacryloxypropyltetramethyldisiloxane 20 - 30% Polyethylene glycol-polydimethylsiloxane-polyethylene glycol 1 - 3% Methyl vinyl ether-maleic anhydride copolymer 2 - 5% The balance is liquid carboxyl-terminated polycaprolactone.

6. The preparation method of a sole with stable adhesion according to claim 5, characterized in that, The EMH powder-carboxyl-terminated polycaprolactone blend dispersion is prepared by the following method: Weigh polyethylene glycol-polydimethylsiloxane-polyethylene glycol, methyl vinyl ether-maleic anhydride copolymer, and EMH powder according to weight percentages, mix them evenly, then add liquid carboxyl-terminated polycaprolactone and bis-3-methacryloxypropyltetramethyldisiloxane, and mix them evenly to obtain the EMH powder-carboxyl-terminated polycaprolactone blend dispersion.

7. The preparation method of a sole with stable adhesion according to claim 1, characterized in that, It also includes preheating the bottom surface of the midsole, with the temperature being 100 - 110 °C and the time being 1 - 2 min.

8. The preparation method of a sole with stable adhesion according to claim 1, characterized in that: The midsole contains an EMH powder-carboxyl-terminated polycaprolactone blend dispersion.

9. The preparation method of a sole with stable adhesion according to claim 1, characterized in that, The unvulcanized and sticky rubber compound is prepared by the following method: Weigh the mixed rubber according to parts by weight, roll it, heat it to 100 - 120 °C, add the EMH powder-carboxyl-terminated polycaprolactone blend dispersion, mix it evenly, then cool it down to 35 - 45 °C, add the vulcanizing agent, and mix it evenly to obtain the unvulcanized and sticky rubber compound.

10. A sole with stable adhesion, comprising a midsole and an outsole, characterized in that: The midsole is fixedly connected to the bottom, and this sole is obtained by the preparation method of a sole with stable adhesion according to any one of claims 1 - 9.

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