Lightweight transparent high-heat and wear-resistant rubber and plastic sole by molding and preparation method thereof

Abstract

The present application provides a kind of light transparent high heat wear-resistant rubber sole of moulding and its preparation method, by mass parts, consisting of: 50-60 parts of high hardness thermoplastic resin;10-20 parts of polydiene rubber;20-30 parts of mixing type polyurethane;3-5 parts of heat conduction auxiliary agent;0.5-1 parts of antioxidant;0.1-0.3 parts of ultraviolet absorber;0.1-0.3 parts of lubricant;0.3-0.5 parts of crosslinking agent.The above defined components are mixed by internal mixer, then flat plate moulding vulcanization is carried out, to obtain a kind of light transparent high heat wear-resistant rubber sole of moulding.Light transparent high heat wear-resistant rubber sole adds nanometer spherical alumina as heat conduction auxiliary agent, effectively reduces the light scattering caused by the difference of refractive index of filler and matrix and particle agglomeration, at the same time of giving the material heat conduction function, maximizes the original transparent texture, especially suitable for basketball, racing and other high strength sports shoes with high performance requirements.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of rubber soles, in particular to a light and transparent high-heat and wear-resistant rubber-plastic outsole formed by molding and a preparation method thereof. BACKGROUND

[0002] Transparent rubber outsoles are widely used in high-grade sports shoes due to their unique appearance, wear resistance, and strong grip, but their self-weight is large, and the density of the vulcanized and shaped outsole is 1.15-1.2 g / cm 3 Therefore, it is difficult to meet the light weight requirements of some high-intensity sports such as basketball and marathon. In order to improve the light weight of the transparent outsole, a rubber-plastic formula outsole material appears on the market, which is made of high-strength thermoplastic elastomers such as POE and EVA, has a low density (usually less than 1.0 g / cm 3 ), a high hardness (greater than 80A), is combined with conventional rubber (such as butadiene, styrene butadiene, and isoprene rubber), has low or no white smoke filling, is formed by injection molding, and can obtain a light weight (density of about 0.9 g / cm 3 ), high wear resistance (room temperature DIN less than 50 mm 3 ) rubber outsole, and has a transparent appearance. However, in actual wearing process, the rubber outsole is severely worn, especially in high-intensity sports such as basketball and speed running, the friction between the outsole and the ground is intense, and local heat causes the material to soften and is not wear-resistant.

[0003] In order to solve the problem of insufficient heat and wear resistance of the transparent rubber-plastic outsole in the prior art and the difficulty in meeting the requirements of high-intensity sports, the present application provides a light and transparent high-heat and wear-resistant rubber outsole formed by molding, which effectively improves the wear resistance of the material by introducing a mixed polyurethane rubber, and simultaneously synergistically enhances the thermal stability and heat and wear resistance of the material by compounding nano spherical alumina. The composite system finally enables the prepared outsole to have excellent comprehensive wear resistance while maintaining the transparent and light weight properties, and is particularly suitable for high-intensity sports shoes such as basketball and speed running which have high requirements for the performance of the outsole. SUMMARY

[0004] To achieve the above-mentioned purpose, the technical solution adopted by the present application is as follows: a light and transparent high-heat and wear-resistant rubber-plastic outsole formed by molding, consisting of the following materials in mass parts:

[0005] 50-60 parts of high-hardness thermoplastic resin;

[0006] 10-20 parts of polydiene rubber;

[0007] 20-30 parts of mixed polyurethane;

[0008] 3-5 parts of heat-conducting aid;

[0009] 0.5-1 part of an antioxidant;

[0010] 0.1-0.3 parts of an ultraviolet absorber;

[0011] 0.1-0.3 parts of a lubricant;

[0012] 0.3-0.5 parts of a crosslinking agent.

[0013] In the above technical solution, the high-hardness thermoplastic resin has a hardness higher than 80A and a melting temperature lower than 120℃, and can be composed of one or more of ethylene-vinyl acetate copolymer (EVA) and thermoplastic polyolefin elastomer (POE).

[0014] In the above technical solution, the polydiene rubber is one or both of solution styrene-butadiene rubber and brominated butyl rubber.

[0015] In the above solution, the mixing type polyurethane is polymerized from polyether polyol and diphenyl methane diisocyanate, and has a molecular weight higher than 20000.

[0016] In the above solution, the heat-conducting assistant is nanometer spherical alumina.

[0017] In the above solution, the antioxidant is 2,6-di-tert-butyl-p-cresol.

[0018] In the above solution, the ultraviolet absorber is 2-(2'-hydroxy-5'-methylphenyl) benzotriazole.

[0019] In the above solution, the lubricant is stearic acid.

[0020] In the above solution, the crosslinking agent is a peroxide crosslinking agent.

[0021] A preparation method of a light-weight transparent high-heat wear-resistant non-slip rubber outsole formed by mold pressing, comprising the following steps:

[0022] Step 1: weigh each component material according to the above defined proportion, and then add all the weighed components except the crosslinking agent into a banbury mixer for mixing, and turn the materials for 4-5 times, until the temperature rises to 110-120℃, then add the weighed crosslinking agent, and continue mixing for 3-5 minutes, and finally granulate the uniformly mixed mixture, and place the prepared granules for cooling;

[0023] Step 2: add the cooled granules in step 1 into a mold for flat mold pressing vulcanization, and the vulcanization temperature is 165-170℃, and the vulcanization time is 400-500 seconds.

[0024] By adopting the above technical solution, the present application has the following beneficial effects:

[0025] The high-hardness thermoplastic resin ensures the hardness and light weight of the rubber-thermoplastic outsole; the polydiene rubber improves the skid resistance of the material; the mixing type polyurethane improves the wear resistance of the material. The nanometer spherical aluminum oxide is added as a heat conduction aid. The aluminum oxide can conduct and diffuse the heat generated by the severe friction between the outsole and the ground, avoiding the local temperature from being too high to soften, thereby improving the high-temperature wear resistance of the material; compared with the heat conduction aid zinc oxide, the refractive index of the aluminum oxide is closer to that of the outsole material, effectively reducing the light scattering caused by the difference in refractive index between the filler and the matrix and the particle agglomeration, while imparting the material with the heat conduction function, the original transparent texture is preserved to the greatest extent. The prepared outsole material has a transparent appearance, the density is 0.92-0.98 g / cm 3 , DIN (150℃) 50-55 mm, dry skid resistance is greater than 0.9, wet skid resistance is greater than 0.7, which can meet the performance requirements of light weight, wear resistance and skid resistance of the outsole of sports shoes.

[0026] The thermoplastic polymer is added to the rubber formula to improve the flowability of the rubber material, meet the molding process, the process flow is simple, and the cost is low. DETAILED DESCRIPTION

[0027] The technical solutions in the embodiments of the present application will be described clearly and completely below. Obviously, the described embodiments are only part of the embodiments of the present application, rather than all the embodiments. Based on the embodiments in the present application, all other embodiments obtained by those skilled in the art without creative labor are within the scope of protection of the present application.

[0028] The present application provides a molding light-weight transparent high-heat wear-resistant rubber-thermoplastic outsole, which is composed of the following materials in mass parts:

[0029] 50-60 parts of high-hardness thermoplastic resin;

[0030] 10-20 parts of polydiene rubber;

[0031] 20-30 parts of mixing type polyurethane;

[0032] 3-5 parts of heat conduction aid;

[0033] 0.5-1 part of anti-aging agent;

[0034] 0.1-0.3 parts of ultraviolet absorber;

[0035] 0.1-0.3 parts of lubricant;

[0036] 0.3-0.5 parts of crosslinking agent.

[0037] The high hardness thermoplastic resin ethylene-vinyl acetate copolymer (EVA), thermoplastic polyolefin elastomer (POE) one or more components, hardness is higher than 80A, melting temperature is lower than 120℃, density is lower than 0.95 g / cm 3 , melt index is greater than 1 g / 10 min (190℃, 2.16Kg). This kind of polymer is usually low crystalline polymer, transparent state, can ensure the transparency of the prepared sole, its hardness is high, tear, tensile strength is large, ensures the mechanical strength of the prepared sole, it is used as EVA foaming sole, has good flow processing performance. As preferred, the model of the high hardness thermoplastic resin includes one or more of EVA 7470M, EVA 7350M, POE ENGAGE 8003, POE ENGAGE 8480.

[0038] The polydiene rubber is one or both of solution styrene-butadiene rubber and brominated butyl rubber. From the point of view of rubber viscoelasticity, the value of loss factor tan delta of rubber at 0℃ is usually improved, and the wet skid resistance is improved. Solution styrene-butadiene rubber and brominated butyl rubber are a kind of high damping rubber, and their tan delta values are high in a wide temperature range, so their wet skid resistance is good, and the introduction of them into the formula can improve the skid resistance of the sole material. As preferred, the model of the polydiene rubber includes one or both of BIIR X2 (brominated butyl rubber) and SSBR 1205 (solution styrene-butadiene rubber).

[0039] The mixing type polyurethane is polymerized from polyol and diisocyanate. The mixing type polyurethane has excellent wear resistance, and its thermal wear resistance is good, and the introduction of it into the formula can improve the wear resistance of the sole material. As preferred, the mixing type polyurethane is synthesized by the reaction of diphenyl methane diisocyanate and polyether polyol, and its molecular weight is greater than 20000, which is provided by Huafeng.

[0040] The mixing type polyurethane synthesized by the reaction of diphenyl methane diisocyanate and polyether polyol can be crosslinked by peroxide, which is suitable for crosslinking system such as EVA and POE, and can be co-crosslinked, and its wear resistance and heat resistance are further improved after crosslinking.

[0041] The heat-conducting assistant is nanometer spherical alumina. Alumina has good heat conductivity and is often used as a heat-conducting filler of polymer. The addition of alumina to the outsole material can improve the heat-conducting performance of the outsole material. When the outsole material is rubbed against the ground, the generated heat can be conducted and diffused, avoiding local temperature rise and softening and thus avoiding abrasion. The refractive index of the conventional heat-conducting assistant, zinc oxide, is about 2.0, which is quite different from that of the outsole material (1.5). When zinc oxide is added to the outsole material, the outsole material loses its transparency. The refractive index of the nanometer spherical alumina is about 1.76, which is closer to that of the outsole material. When the nanometer spherical alumina is added to the outsole material, the nanometer spherical alumina has little effect on the transparency of the outsole material. Meanwhile, the dispersion of the nanometer spherical alumina in the material matrix can significantly improve the physical properties of the material, avoiding local stress concentration and damage and thus enhancing the material. As a preferred embodiment, the heat-conducting assistant is nanometer spherical alumina, which is provided by Zhejiang Zhiti Nano Micro New Material Co., Ltd.

[0042] The anti-aging agent is an assistant that can delay or inhibit the aging process of the formed rubber. As a preferred embodiment, the anti-aging agent is di-tert-butyl-p-cresol.

[0043] The ultraviolet absorber is an assistant that can effectively prevent the damage of ultraviolet rays to the product and greatly improve the anti-aging performance of the product. As a preferred embodiment, the ultraviolet absorber is 2-(2'-hydroxy-5'-methylphenyl) benzotriazole.

[0044] The lubricant is a processing assistant that can improve the flowability of the material and change the surface properties of the material, thereby avoiding the problem that the mixture is easily adhered to the inner wall of the internal mixer during mixing and the problem that the mixture is easily adhered to the mold during mold pressing. As a preferred embodiment, the lubricant is stearic acid.

[0045] The cross-linking agent is a substance that can produce a cross-linking network of the linear molecules of the polymer, thereby increasing the strength and heat resistance of the polymer. As a preferred embodiment, the cross-linking agent is an organic peroxide, specifically dicumyl peroxide.

[0046] The application also provides a preparation method of the mold-pressed light and transparent high-heat and wear-resistant rubber and plastic outsole, which comprises the following steps:

[0047] Step 1: The components are weighed according to the above defined proportions, and then the weighed components except the cross-linking agent are added to an internal mixer for mixing, and the materials are turned over for 4-5 times. When the temperature rises to 110-120℃, the weighed cross-linking agent is added, and the mixing is continued for 3-5 minutes. Finally, the uniformly mixed mixture is granulated, and the prepared granules are cooled.

[0048] Step 2: The cooled granules in step 1 are added to a mold for flat mold pressing and vulcanization, and the vulcanization temperature is 165-170℃ and the vulcanization time is 400-500 seconds.

[0049] In order to further illustrate the present application, the molded light weight transparent high heat and wear resistant rubber and plastic outsole and the preparation method thereof provided by the present application are described in detail below in combination with examples, but they should not be understood as limiting the scope of protection of the present application.

[0050] Embodiment

[0051] Examples 1-6

[0052] A molded light weight transparent high heat and wear resistant rubber and plastic outsole, according to the formulation table in Table 1, the component materials of examples 1-6 were weighed according to the proportion for standby.

[0053] Table 1 Formulation composition of examples 1-6

[0054] Example 7

[0055] A preparation method of a molded light weight transparent high heat and wear resistant rubber and plastic outsole

[0056] Step 1: according to the formulation composition in Table 1, the component materials were weighed, and then the weighed components except the crosslinking agent were added into the internal mixer for mixing, and the material was turned over for 4-5 times, and then the temperature was raised to 110-120℃, and then the weighed crosslinking agent was added, and the mixing was continued, and the time was controlled for 3-5 min, and finally the mixed mixture was granulated, and the prepared particles were placed for cooling;

[0057] Step 2: the cooled particles in step 1 were added into the mold for flat mold pressing vulcanization, the vulcanization temperature was 165-170℃, and the vulcanization time was 400-500 seconds. The molded light weight transparent high heat and wear resistant rubber and plastic outsole in examples 1-6 was prepared.

[0058] Comparative examples 1-3

[0059] According to the formulation table in Table 2, the rubber and plastic molded outsole was prepared according to the steps of example 7.

[0060] Table 2 Formulation composition of comparative examples 1-3

[0061] Comparative example 4

[0062] According to the formulation of example 2 in Table 1, the rubber outsole was prepared according to the following injection molding steps.

[0063] Step 1: ingredients are weighed according to the formulation of Example 1 in Table 1, and then the weighed ingredients except the crosslinking agent are added into the internal mixer for mixing, and the mixing is carried out for 4-5 times, and then the temperature is increased to 110-120℃, and then the weighed crosslinking agent is added, and the mixing is continued for 3-5 minutes, and finally the mixed mixture is granulated, and the prepared particles are cooled;

[0064] Step 2: the cooled particles in Step 1 are injected into the EVA shoe sole mold pressing machine gun, the temperature of the gun is set to 75-95℃, the material is fed, and the molten material is injected into the mold through the gun, and the mold is closed and heated and vulcanized, the vulcanization temperature is 170-175℃, and the vulcanization time is 400-500 seconds.

[0065] The EVA foaming materials prepared in the examples and comparative examples are subjected to physical property test, and the results are shown in Table 3.

[0066] Table 3: physical property test results of examples and comparative examples

[0067]

[0068] Note: the heat wear resistance refers to DIN wear resistance tested under high temperature (150℃) conditions, and the equipment has the function of setting the roller temperature, and the test equipment used is a high temperature type DIN wear resistance tester (GT-7012-DH1).

[0069] From Example 1 to Example 3, the increase of the mixing type polyurethane content leads to a slight decrease of the hardness, while maintaining good slip resistance performance, and improving the mechanical properties and wear resistance of the material. The content of the thermal conductive agent is different in Example 1, Example 5 and Example 6, and the thermal conductive agent is a functional filler, and the change of its content significantly affects the performance of the composite material. The appropriate addition of the thermal conductive agent can optimize the comprehensive performance, and the content is too low, which is not functional enough, and the content is too high, which damages the matrix and leads to performance degradation.

[0070] Compared with Comparative Example 1, the polydiene rubber (solution polymerized butadiene or brominated butyl rubber) with excellent slip resistance performance is introduced into the formula of the examples of the present application, which can greatly improve the slip resistance performance of the outsole material, and the prepared outsole material meets the performance requirements of high wear resistance and slip resistance. In addition, the formula of the present application is developed on the basis of the formula of EVA rubber and plastic molding, and it can maintain the characteristics of light weight and transparency of the rubber and plastic outsole.

[0071] Compared with Comparative Example 2, the mixing type polyurethane with excellent wear resistance is introduced into the formula of the examples of the present application, which can improve the wear resistance of the outsole material. The mixing type polyurethane synthesized by the reaction of diphenyl methane diisocyanate and polyether polyol can be crosslinked by peroxide, and it is compatible with the crosslinking system of EVA, POE, etc., and can be co-crosslinked, and its wear resistance is further improved after crosslinking.

[0072] Compared with Comparative Example 3, the inventive example uses nanometer spherical alumina as a functional heat-conducting additive in the formula instead of using white carbon black which only has a reinforcing filling effect. This selection improves the heat and wear resistance of the outsole material at high temperatures. The prepared outsole material has more consistent wear resistance at room temperature and high temperature while maintaining excellent slip resistance, effectively solving the problem of inaccurate evaluation of the actual wear resistance of the shoe sole.

[0073] Compared with Comparative Example 4, the inventive example preferably uses a mold pressing process. The mild and uniform heating method in the mold pressing process can effectively avoid the yellowing and degradation of the rubber and plastic material under high-temperature shear. At the same time, the internal stress of the material is smaller and the structure is more uniform under this process, providing favorable conditions for the nanometer spherical alumina to build an efficient heat-conducting network, thereby more fully exerting the advantages of the formula design in improving the heat and wear resistance and slip resistance, effectively improving the problem of deviation of the room temperature test wear resistance and the actual wear resistance.

[0074] The above only describes the preferred embodiments of the present application, and it should be noted that for those skilled in the art, without departing from the principles of the present application, several improvements and refinements can be made, and these improvements and refinements should also be considered within the scope of protection of the present application.

Claims

1. A molded, lightweight, transparent, heat-resistant, wear-resistant rubber-plastic outsole, characterized in that, By weight, it comprises the following materials: 50-60 parts of high-hardness thermoplastic resin; 10-20 parts of polydiolefin rubber; 20-30 parts of compounded polyurethane; 3-5 parts of thermally conductive agent; 0.5-1 part of antioxidant; 0.1-0.3 parts of ultraviolet absorber; 0.1-0.3 parts of lubricant; and 0.3-0.5 parts of crosslinking agent. The high-hardness thermoplastic resin has a hardness higher than 80A and a melting temperature lower than 120°C, and is composed of one or more of ethylene-vinyl acetate copolymer and thermoplastic polyolefin elastomer. The polydiolefin rubber is one or both of solution-polymerized styrene-butadiene rubber and brominated butyl rubber. The compounded polyurethane is polymerized from polyether polyol and diphenylmethane diisocyanate, and its molecular weight is above 20,000. The thermally conductive agent is nano-spherical alumina; The method for preparing the lightweight, transparent, heat-resistant, and abrasion-resistant rubber-plastic outsole by compression molding includes the following steps: (1) Weigh each component material according to the proportion of the material, and then add each component except the crosslinking agent to the internal mixer for internal mixing. Turn the material 4 to 5 times. When the temperature rises to 110 to 120°C, add the weighed crosslinking agent and continue mixing. Finally, granulate the uniformly mixed mixture and let the granulated particles cool. (2) Add the cooled particles from step (1) into the mold for flat molding vulcanization. The vulcanization temperature is 165-170℃ and the vulcanization time is 400-500 seconds. In step (1), the mixing time after adding the crosslinking agent is 3-5 minutes.

2. The lightweight, transparent, heat-resistant, and wear-resistant rubber-plastic outsole molded as described in claim 1, characterized in that... The antioxidant is 2,6-di-tert-butyl-p-methylphenol; the ultraviolet absorber is 2-(2'-hydroxy-5'-methylphenyl)benzotriazole; the lubricant is stearic acid; and the crosslinking agent is a peroxide crosslinking agent.

3. A method for preparing a lightweight, transparent, heat-resistant, wear-resistant rubber-plastic outsole by compression molding as described in any one of claims 1-2, characterized in that, Includes the following steps: (1) Weigh each component material according to the proportion of the material, and then add each component except the crosslinking agent to the internal mixer for internal mixing. Turn the material 4 to 5 times. When the temperature rises to 110 to 120°C, add the weighed crosslinking agent and continue mixing. Finally, granulate the uniformly mixed mixture and let the granulated particles cool. (2) Add the cooled particles from step (1) to the mold for flat molding vulcanization. The vulcanization temperature is 165-170℃ and the vulcanization time is 400-500 seconds.

4. The preparation method according to claim 3, characterized in that... In step (1), the mixing time after adding the crosslinking agent is 3-5 minutes.

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