Ultra-light high-resilience cushioning transparent EVA (Ethylene Vinyl Acetate) composite chemical foaming material as well as preparation method and application thereof

Abstract

The invention provides an ultralight high-resilience cushioning transparent EVA composite chemical foaming material. The ultralight high-resilience cushioning transparent EVA composite chemical foaming material is prepared from the following raw materials in parts by mass: 30-60 parts of high-transparency modified TPX, 30-50 parts of an ethylene-vinyl acetate copolymer, 7-25 parts of a thermoplastic elastomer TPE, 5-16 parts of an olefin block copolymer, 5-10 parts of a wear-resistant agent, 0.2-0.5 part of stearic acid, 0.2-1 part of zinc stearate, 0.3-1.5 parts of an odorless bridging agent and 3.5-8 parts of a transparent foaming agent, the high-transparency modified TPX is prepared from high-transparency TPX, EVOH, ethylene propylene diene monomer and stearic acid. The EVA composite chemical foaming material provided by the invention has the advantages of ultralight weight, low shock absorption, high resilience, high transparency and high energy feedback, keeps the wearing comfort of shoes, protects a consumer from fatigue, pain and even injury caused by the material shock absorption problem in the exercise process, is high in cost performance, and meets the comprehensive requirements of the consumer.

Description

Technical Field

[0001] The present invention belongs to the technical field of foamed soles, and particularly relates to an ultra-light, high-elasticity, shock-absorbing, transparent EVA composite chemical foaming material, a preparation method thereof, and an application thereof. Background Art

[0002] Among various ultra-light sports running shoes made by chemical foaming on the market, the specific gravity is up to 0.09 g / cm 3 , which is light, but has a large foaming ratio, and poor resilience, shock absorption and compression set performance. After 10 km of high-intensity running, its comfort and resilience drop significantly. When running, it feels like stepping directly on the road surface, and the shock absorption performance of the sole is poor, which is likely to cause damage to the feet and the meniscus of the knee joint. The reason is that when setting the sole material, only the reduction of the material specific gravity and the test of the test piece resilience rate are emphasized, while the resilience performance of the front sole of the shoe and the shock absorption performance of the heel of the shoe are ignored. The excellent shock absorption performance of the material can reduce the pressure borne by the feet and knees, making consumers run more easily and comfortably. Moreover, the transparency is poor, which limits the design space and cannot meet the needs of some consumers who like colorful and visual displays. Although supercritical physical foaming can solve the above problems, the unit price is expensive, which is not cost-effective for ordinary consumers.

[0003] Therefore, developing an economical, ultra-light, high-elasticity, shock-absorbing, transparent EVA composite chemical foaming material has become a problem to be solved. By the shock absorption of the material to reduce the pressure borne by the feet and knees and maintain the high-elasticity and low-specific gravity performance of the material, when the general consumers who like ultra-light shoes run or carry out other sports, they will not be fatigued, painful or even injured due to the continuous impact force from the ground on the feet, making running truly become a relaxed and comfortable lifestyle, thus driving the trend of national sports, and the market prospect is relatively good. Summary of the Invention

[0004] In view of this, the technical problem to be solved by the present invention is to provide an ultra-light, high-elasticity, shock-absorbing, transparent EVA composite chemical foaming material, a preparation method thereof, and an application thereof. The EVA composite chemical foaming material provided by the present invention has ultra-light weight, high elasticity, shock absorption, high transparency and compression resistance performance.

[0005] The present invention provides an ultra-light, high-elasticity, shock-absorbing, transparent EVA composite chemical foaming material, comprising the following raw materials in parts by mass:

[0006] High-transparency modified TPX: 30-60 parts, ethylene-vinyl acetate copolymer: 30-50 parts, thermoplastic elastomer TPE: 7-25 parts, olefin block copolymer: 5-16 parts, wear-resistant agent: 5-10 parts, stearic acid: 0.2-0.5 part, zinc stearate: 0.2-1 part, odorless cross-linking agent: 0.3-1.5 parts, transparent foaming agent: 3.5-8 parts;

[0007] The highly transparent modified TPX is prepared from highly transparent TPX, EVOH, ethylene propylene diene monomer rubber and stearic acid.

[0008] Preferably, the raw materials for preparing the highly transparent modified TPX include:

[0009] 50 to 70 parts by mass of highly transparent TPX;

[0010] 35 to 45 parts by mass of EVOH;

[0011] 15 to 25 parts by mass of ethylene propylene diene monomer rubber;

[0012] 0.5 to 0.8 parts by mass of stearic acid.

[0013] Preferably, the preparation method of the highly transparent modified TPX includes the following steps:

[0014] a) Knead the highly transparent TPX and stearic acid, then add EVOH for homogenization to obtain a mixture melt;

[0015] Extrude the mixture melt with a twin-screw extruder and then dry it to obtain a mixture;

[0016] b) Knead the mixture and stearic acid, then add ethylene propylene diene monomer rubber for homogenization to obtain a mixture melt;

[0017] Extrude the mixture melt and then extrude it with a twin-screw extruder and dry it to obtain the highly transparent modified TPX.

[0018] Preferably, the highly transparent TPX is selected from one or more of highly transparent TPX with models PMPMX001, PMPMX002, PMP MX004, PMPMX021, PMP MX022;

[0019] The EVOH is selected from one or more of EVOH with models EV2904F, EV2951F, EV3251F, EV3851F, EV4405F, EV4451F;

[0020] The ethylene propylene diene monomer rubber is selected from one or more of ethylene propylene diene monomer rubber with models 3745, 3760, 3762.

[0021] Preferably, the ethylene vinyl acetate copolymer is selected from one or several of ethylene vinyl acetate copolymers with models EVA7470M, EVA7350M, EVA7360M, EVA40W.

[0022] Preferably, the olefin block copolymer is selected from one or more of olefin block copolymers with model numbers OBC9107, OBC9007, OBC9500, and OBC9530.

[0023] Preferably, the thermoplastic elastomer TPE is selected from one or more of medium thermoplastic elastomer TPEs with model numbers T-Blend Live Granule 4008-80T, 4008-60N, and 4003-85T.

[0024] Preferably, the wear-resistant agent is a pre-dispersed silicone masterbatch wear-resistant agent.

[0025] The present invention also provides a preparation method for the above-mentioned ultra-light, high-resilience, shock-absorbing, and transparent EVA composite chemical foaming material, which includes the following steps:

[0026] A) Mix and granulate high-transparency modified TPX, ethylene-vinyl acetate copolymer, thermoplastic elastomer TPE, olefin block copolymer, wear-resistant agent, stearic acid, and zinc stearate to obtain a mixture.

[0027] B) Mix and granulate the mixture, odorless crosslinking agent, and transparent foaming agent to obtain a material to be foamed.

[0028] C) Foam the material to be foamed to obtain a foamed material.

[0029] The present invention also provides a sole prepared from the above-mentioned ultra-light, high-resilience, shock-absorbing, and transparent EVA composite chemical foaming material.

[0030] Compared with the prior art, the present invention provides an ultra-light, high-resilience, shock-absorbing, and transparent EVA composite chemical foaming material, which includes the following raw materials in parts by mass: high-transparency modified TPX: 30-60 parts, ethylene-vinyl acetate copolymer: 30-50 parts, thermoplastic elastomer TPE: 7-25 parts, olefin block copolymer: 5-16 parts, wear-resistant agent: 5-10 parts, stearic acid: 0.2-0.5 parts, zinc stearate: 0.2-1 part, odorless crosslinking agent: 0.3-1.5 parts, transparent foaming agent: 3.5-8 parts; the high-transparency modified TPX is prepared from high-transparency TPX, EVOH, ethylene-propylene-diene monomer rubber, and stearic acid. The EVA composite chemical foaming material provided by the present invention has the characteristics of ultra-light weight, low shock absorption, high resilience, high transparency, and high energy feedback, maintaining the wearing comfort of shoes, protecting consumers from fatigue, pain, and even injury caused by material shock absorption problems during exercise, and having high cost performance, meeting the comprehensive needs of consumers. Specific Embodiments

[0031] The present invention provides an ultra-light, high-resilience, shock-absorbing, and transparent EVA composite chemical foaming material, which includes the following raw materials in parts by mass:

[0032] Highly transparent modified TPX: 30 - 60 parts, ethylene - vinyl acetate copolymer: 30 - 50 parts, thermoplastic elastomer TPE: 7 - 25 parts, olefin block copolymer: 5 - 16 parts, wear - resistant agent: 5 - 10 parts, stearic acid: 0.2 - 0.5 parts, zinc stearate: 0.2 - 1 part, odorless cross - linking agent: 0.3 - 1.5 parts, transparent blowing agent: 3.5 - 8 parts;

[0033] The highly transparent modified TPX is prepared from highly transparent TPX, EVOH, ethylene - propylene - diene monomer rubber and stearic acid.

[0034] The preparation raw materials of the ultra - light, highly elastic and shock - absorbing transparent EVA composite chemical foaming material provided by the present invention include 30 - 60 parts of highly transparent modified TPX. It can be 30, 35, 40, 45, 50, 55, 60, or any value between 30 - 60 parts.

[0035] Among them, the highly transparent modified TPX is prepared from highly transparent TPX, EVOH, ethylene - propylene - diene monomer rubber and stearic acid.

[0036] Specifically, the preparation raw materials of the highly transparent modified TPX include:

[0037] 50 - 70 parts by mass of highly transparent TPX;

[0038] 35 - 45 parts by mass of EVOH;

[0039] 15 - 25 parts by mass of ethylene - propylene - diene monomer rubber;

[0040] 0.5 - 0.8 parts by mass of stearic acid.

[0041] The raw materials for preparing the highly transparent modified TPX include: 50 to 70 parts by mass of highly transparent TPX, which can be 50, 52, 55, 57, 60, 62, 65, 67, 70, or any value between 50 and 70 parts by mass. In the highly transparent modified TPX material, the proportion of highly transparent TPX is at least 40%, and this proportion ensures the low specific gravity, high resilience performance, and high transparency of the composite material. The highly transparent TPX is selected from one or more of the highly transparent TPX with models PMPMX001, PMPMX002, PMPMX004, PMPMX021, and PMPMX022. Highly transparent TPX is a copolymer of 4-methylpentene and a small amount of α-olefins (such as hexene), an α-olefin with an isotactic structure having an isobutyl side chain (R = CH2CH(CH3)2, where R represents the side chain), with a unique chain structure and helical structure, making it not only have excellent mechanical properties but also possess properties such as low density and high light transmittance. Compared with homopolymerization, the copolymerized TPX has good comprehensive performance, good processing performance, good impact resistance, good heat resistance, good dimensional stability, excellent low-temperature toughness, and good transparency, with a required specific gravity of ≤0.83 g / cm 3 , a copolymerized highly transparent TPX with a light transmittance ≥93%, a Vicat softening temperature ≤145°C, a melting point ≤225°C, and a heat distortion temperature of 75°C, is used in the transparent high-elastic ultra-light shock-absorbing EVA composite chemical foamed sole material, which can improve the physical properties of the material that have deteriorated due to the low specific gravity in the market's ultra-light chemical foaming, with a foaming ratio of 2.0 - 2.1, resulting in a decrease in the physical properties of the polymer material after large-scale foaming, affecting wearing comfort, shoe resilience, shock absorption, and other comprehensive physical properties, and can also improve the transparency of the material.

[0042] The raw materials for preparing the highly transparent modified TPX further include: 35 to 45 parts by mass of EVOH, which can be 35, 36, 37, 38, 39, 40, 41, 42, 43, 44, 45, or any value between 35 and 45 parts by mass. The EVOH is selected from one or more of EVOH with models EV2904F, EV2951F, EV3251F, EV3851F, EV4405F, and EV4451F. EVOH is a polymer that combines the processability of ethylene polymers and the barrier effect of vinyl alcohol polymers. It has excellent transparency, resilience, cold resistance, heat resistance, and air barrier properties. It does not contain chlorine and dioxins and is a green environmental protection product. The amorphous EVOH used in the present invention has a relatively disordered molecular arrangement and no obvious melting point. The change in its physical state is a gradual softening process. It is more uniformly mixed with materials having a higher melting point, and the molecular arrangement is relatively loose, making it easy to soften after heating and having good processing performance. EVOH is an environmentally friendly material, and its waste can be recycled and reused without generating harmful substances, meeting the requirements of sustainable development. In the present invention, the requirements for the EVOH raw material are: ethylene content: 25 to 44 mol%, oxygen transmission rate: 0.2 to 1.5 cc / m 2 ·24h·0.1MPa, specific gravity: 1.1 to 1.19 g / cm 3 , melt index: below 210 °C, 1.8 to 5 kg, and it is used in the sole materials of ultra-light, high-resilience, shock-absorbing, and transparent EVA composite chemical foaming formulations. EVOH used for preparing the highly transparent modified TPX material can provide the following advantages: Firstly, as a compatibilizer between TPX and ethylene propylene diene monomer rubber, it enables two polymer materials with different melting points and ultra-light specific gravities to be compatible; secondly, the excellent barrier performance of EVOH can effectively solve the problem of the decline in resilience performance caused by gas penetration after the decomposition of the blowing agent; thirdly, the EVOH material also has high transparency performance, and together with highly transparent TPX and transparent ethylene propylene diene monomer rubber, it provides the guarantee of low specific gravity, high transparency, and high resilience for the present invention.

[0043] The raw materials for preparing the highly transparent modified TPX further include: 15 to 25 parts by mass of ethylene propylene diene monomer (EPDM), which can be 15, 16, 17, 18, 19, 20, 21, 22, 23, 24, 25, or any value between 15 and 25. The EPDM is selected from one or more of the EPDM with models 3745, 3760, and 3762. EPDM is a copolymer of ethylene, propylene, and a small amount of non-conjugated diene, and it is a kind of ethylene-propylene rubber. Due to the existence of multiple unsaturated double bonds in its molecular structure, the connection between molecules is relatively loose, and it is prone to self-reaction at high temperatures, resulting in molecular volume shrinkage. Therefore, its aging resistance such as ozone resistance, heat resistance, and weather resistance is excellent. With a low melting point, it can be used in transparent high-elastic ultra-light EVA composite chemical foaming sole materials to improve the problem of poor dispersion caused by the high melting point of the modified material and increase the rebound performance of the material. In the present invention, it is required that the specific gravity of the EPDM ≤ 0.86 g / cm 3 , the Mooney viscosity ML(1+4) at 125 °C is 40 - 50 MU, the propylene content is 25 - 30 wt%, and the ethylene content is 70 - 75 wt%.

[0044] The raw materials for preparing the highly transparent modified TPX further include: 0.5 to 0.8 parts by mass of stearic acid, which can be 0.5, 0.6, 0.7, 0.8, or any value between 0.5 and 0.8.

[0045] In the present invention, the preparation method of the highly transparent modified TPX includes the following steps:

[0046] a) Knead the highly transparent TPX and stearic acid, and then add EVOH for homogenization to obtain a mixture melt;

[0047] Extrude the mixture melt with a twin-screw extruder and then dry it to obtain a mixture;

[0048] b) Knead the mixture and stearic acid, and then add EPDM for homogenization to obtain a mixture melt;

[0049] Extrude the mixture melt with a twin-screw extruder and then dry it to obtain the highly transparent modified TPX.

[0050] Specifically, add the highly transparent TPX and stearic acid to the hopper of a twin-screw granulator for kneading, convey it to the homogenization area, add EVOH at the side feeding port for homogenization to obtain a mixture melt.

[0051] Extrude the mixture melt through the head to form a continuous strip, then extrude, cool, and cut into pellets, and bake and dry them with a dryer for later use. Among them, the temperature of the twin-screw granulator is 230 - 235 °C.

[0052] Next, the mixture and stearic acid are added together to the hopper of a twin-screw granulator for kneading and conveying to the homogenization area, and ethylene propylene diene monomer rubber is added at the side feeding port for homogenization.

[0053] Finally, the homogenized mixture melt is extruded through a die head to form a continuous strip, then extruded, cooled and pelletized, and dried by a dryer for standby use, and a highly transparent TPX modified material can be obtained. Among them, the temperature of the twin-screws of the granulator is 195 - 200 °C.

[0054] The preparation raw materials of the ultra-light, high-elasticity and shock-absorbing transparent EVA composite chemical foaming material provided by the present invention further include 30 - 50 parts of ethylene-vinyl acetate copolymer, which can be 30, 32, 35, 37, 40, 42, 45, 47, 50, or any value between 30 - 50 parts. In the present invention, the VA (vinyl acetate) content in the ethylene-vinyl acetate copolymer is 18% - 30%, and the specific gravity is required to be ≤ 0.938 g / cm 3 , with a hardness of 80 - 90 °A. This material has excellent flexibility, high elasticity, good ductility and processability. The ethylene-vinyl acetate copolymer is selected from one or more of the ethylene-vinyl acetate copolymers of the models EVA7470M, EVA7350M, EVA7360M, and EVA40W.

[0055] The preparation raw materials of the ultra-light, high-elasticity and shock-absorbing transparent EVA composite chemical foaming material provided by the present invention further include 5 - 16 parts of an olefin block copolymer, which can be 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, or any value between 5 - 15 parts. In the present invention, the olefin block copolymer is required to have a specific gravity ≤ 0.866 g / cm 3 , with a hardness of 60 - 83 °A, a melt index of 0.5 - 5.0, and a compression set @ 70 °C of 45%. The olefin block copolymer has excellent high and low temperature stability, elasticity, high temperature compression set and fatigue resistance, especially good elasticity and compressibility at high temperatures. The olefin block copolymer is used in a transparent, highly elastic and ultra-light EVA composite chemical foaming sole material to make up for the self-reaction of ethylene propylene diene monomer rubber during high temperature modification, thereby causing molecular volume shrinkage and maintaining excellent shrinkage performance of the material. The olefin block copolymer is selected from one or more of the models OBC9107, OBC9007, OBC9500, and OBC9530.

[0056] The raw materials for preparing the ultra-light, high-resilience, shock-absorbing, transparent EVA composite chemical foaming material provided by the present invention also include 7 to 25 parts of thermoplastic elastomer TPE, which can be 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23, 24, 25, or any value between 7 and 25 parts. The thermoplastic elastomer TPE requires a specific gravity of ≤0.88g / cm 3 , hardness 88°A, tensile strength 25MPa, tear strength N / mm. Thermoplastic elastomer TPE material has excellent resilience and shock absorption, comfortable hand feel, good elastic touch, and is a safe and environmentally friendly high-performance material. Adding it to the formula of the present invention makes the foaming material have rubber-like high elasticity and high strength, can withstand repeated deformation and stress, and can effectively absorb and disperse impact energy, thereby playing a shock-absorbing role. In addition, the high elasticity of TPE material means that it can quickly restore its original shape when subjected to external force, which can reduce energy loss and improve shock absorption efficiency. The high strength ensures that the material is not easily damaged or failed during long-term use, ensuring the durability of the material's shock absorption effect and high elasticity.

[0057] The raw materials for preparing the ultra-light, high-resilience, shock-absorbing, transparent EVA composite chemical foaming material provided by the present invention also include 5 to 10 parts of a wear-resistant agent, which can be 5, 6, 7, 8, 9, 10, or any value between 5 and 10 parts. The wear-resistant agent is a pre-dispersed silicone masterbatch wear-resistant agent.

[0058] The raw materials for preparing the ultra-light, high-resilience, shock-absorbing transparent EVA composite chemical foaming material provided by the present invention also include 0.2 to 0.5 parts of stearic acid, which may be 0.2, 0.3, 0.4, 0.5, or any value between 0.2 and 0.5 parts.

[0059] The raw materials for preparing the ultra-light, high-resilience, shock-absorbing transparent EVA composite chemical foaming material provided by the present invention also include 0.2 to 1 parts of zinc stearate, which can be 0.2, 0.3, 0.4, 0.5, 0.6, 0.7, 0.8, 0.9, 1.0, or any value between 0.2 and 1 parts.

[0060] The raw materials for preparing the ultra-light, high-resilience, shock-absorbing, transparent EVA composite chemical foaming material provided by the present invention also include 0.3 to 1.5 parts of an odorless bridging agent, which can be 0.3, 0.4, 0.5, 0.6, 0.7, 0.8, 0.9, 1.0, 1.1, 1.2, 1.3, 1.4, 1.5, or any value between 0.3 and 1.5 parts. The odorless bridging agent is selected from 1,4-di-tert-butyl peroxide isopropylbenzene (BIPB).

[0061] The raw materials for preparing the ultra-light, high-resilience, shock-absorbing and transparent EVA composite chemical foaming material provided by the present invention further include 3.5 to 8 parts of a transparent foaming agent, which can be 3.5, 4, 4.5, 5, 5.5, 6, 6.5, 7, 7.5, 8, or any value between 3.5 and 8. The transparent foaming agent is an odorless white powder with a melting point of 130 to 150 °C and a relative density of 1.55 to 1.65. During the molding process, the transparent foaming agent decomposes a large amount of gas, which is evenly dispersed in the material, and forms a light-transmitting effect on the appearance of the material after cooling.

[0062] After adopting the above-mentioned high-transparency modified TPX thermoplastic elastomer composite material formula, the present invention can obtain an ideal combination of raw material functions. After the high-transparency modified TPX material is blended and foamed, a composite foam with a specific gravity of 0.09 - 0.099 g / cm 3 , a resilience rate of 65 - 72%, a resilience performance of 65 - 72% for the forefoot of the sole, a shock-absorbing G value of 8 - 12% for the heel of the sole, a compression of 38 - 42%, and a light transmittance of 10 - 13% is formed, presenting excellent ultra-lightweight, high-resilience, shock-absorbing, high-transparency, and compression-resistant properties.

[0063] The present invention also provides a preparation method for the above-mentioned ultra-light, high-resilience, shock-absorbing and transparent EVA composite chemical foaming material, comprising the following steps:

[0064] A) Mix and granulate high-transparency modified TPX, ethylene-vinyl acetate copolymer, thermoplastic elastomer TPE, olefin block copolymer, wear-resistant agent, stearic acid, and zinc stearate to obtain a mixture;

[0065] B) Mix and granulate the mixture, odorless cross-linking agent, and transparent foaming agent to obtain a material to be foamed;

[0066] C) Foam the material to be foamed to obtain a foamed material.

[0067] Specifically, in step A), the temperature of the mixing is 125 to 135 °C, which can be 125, 126, 127, 128, 129, 130, 131, 132, 133, 134, 135, or any value between 125 and 135 °C, and the time is 8 to 10 minutes, which can be 8, 9, 10, or any value between 8 and 10 minutes. The granulation time is 9 to 11 minutes, which can be 9, 10, 11, or any value between 9 and 11 minutes, and the temperature is 115 °C to 120 °C, which can be 115, 116, 117, 118, 119, 120, or any value between 115 °C and 120 °C.

[0068] In step B), the temperature of the kneading is 120-125 °C, which can be 120, 121, 122, 123, 124, 125, or any value between 120-125 °C; the time is 5-7 minutes, which can be 5, 6, 7, or any value between 5-7 minutes. The temperature of the granulation is 100-105 °C, which can be 100, 101, 102, 103, 104, 105, or any value between 100-105 °C; the time is 9-11 minutes, which can be 9, 10, 11, or any value between 9-11 minutes.

[0069] In step C), the foaming can be IP injection process or MD compression molding process. Among them, the foaming time of the IP injection process is 400-450 seconds, and the foaming temperature is 175 °C-180 °C. The MD compression molding process includes the steps of foaming in a small foaming mold and secondary molding. Among them, the small foaming time is 600-650 seconds, and the small foaming temperature is 170 °C-175 °C; the heating temperature of the secondary molding is 165-170 °C, the heating time is 420-480 seconds, and after the secondary molding, cooling is carried out. The temperature of the cooling is 10-13 °C, and the cooling time is 420-480 seconds.

[0070] The production process of the ultra-light, high resilience, shock-absorbing, and transparent EVA composite chemical foamed sole material provided by the present invention is simple. Only need to first make a modified high-transparency TPX material, and then load various components into a Lina machine in sequence for kneading. The time is short, the operating conditions are suitable, and the obtained composite material has excellent properties such as high resilience, low specific gravity, low shock absorption, and transparency. The obtained material is granulated and cooled, and then directly formed by small foaming and passed through an oven for shaping to obtain a sole finished product; or the sole finished product with the same effect can also be obtained by adjusting the technical parameters of an IP foaming molding machine.

[0071] The present invention provides a sole, which is prepared from the above ultra-light, high resilience, shock-absorbing, and transparent EVA composite chemical foamed material. When consumers are wearing and exercising, they will not suffer from fatigue, pain, or even injury caused by shoe problems. The ultra-light, high resilience, shock-absorbing, and transparent EVA composite chemical foamed material can maintain the wearing comfort of the shoes, protect consumers from fatigue, pain, or even injury caused by the shock-absorbing problem of the material during exercise, and has a high cost performance, meeting the comprehensive needs of consumers.

[0072] In order to further understand the present invention, the following examples are used to illustrate the ultra-light, high resilience, shock-absorbing, and transparent EVA composite chemical foamed material provided by the present invention, its preparation method, and its application. The protection scope of the present invention is not limited by the following examples.

[0073] In the following examples:

[0074] The wear-resistant agent is a pre-dispersed silicone masterbatch wear-resistant agent;

[0075] The odorless crosslinking agent is BIPB (1,4 - bis(tert - butylperoxy) isopropylbenzene) from AkzoNobel.

[0076] Example 1 (MD)

[0077] The present invention provides an ultra - light, high - resilience, shock - absorbing, transparent EVA composite chemically foamed sole material, which is obtained by foaming a highly transparent modified TPX composite material. The highly transparent modified TPX composite material comprises the following components in parts by mass:

[0078] Highly transparent modified TPX: 35 PHR, ethylene - vinyl acetate copolymer (7350M): 35 PHR, olefin block copolymer (OBC9530): 15 PHR, thermoplastic elastomer TPE (4003 - 85T): 15 PHR, wear - resistant agent: 7.5 PHR, stearic acid: 0.3 PHR, zinc stearate: 1 PHR, odorless crosslinking agent (BIPB): 0.63 PHR, transparent foaming agent (CAP): 6.8 PHR

[0079] Preferably, the preparation method of the highly transparent modified TPX comprises the following steps:

[0080] 1) Weigh the following components in parts by mass: highly transparent copolymer TPX MX021: 60 PHR, EVOH amorphous EV4405F: 40 PHR, stearic acid: 0.3 PHR;

[0081] 2) Add the highly transparent TPX and stearic acid weighed in step 1) into the hopper of a twin - screw granulator for mixing and kneading, convey it to the homogenization area, and add EVOH at the side feeding port for homogenization.

[0082] 3) Extrude the homogenized mixture melt through the die head to form a continuous strip, then extrude, cool and pelletize it. After drying it in a dryer, it is ready for use. The temperature of the twin - screw is 230 - 235 °C.

[0083] 4) Weigh 70 PHR of the pellets produced in step 3), ethylene propylene diene monomer (3745) + 30 PHR, and stearic acid 0.3 PHR in parts by mass;

[0084] 5) Add the pellets and stearic acid weighed in step 4) together into the hopper of a twin - screw granulator for mixing and kneading, convey it to the homogenization area, and add ethylene propylene diene monomer at the side feeding port for homogenization.

[0085] 6) Extrude the homogenized mixture melt through the die head to form a continuous strip, then extrude, cool and pelletize it. After drying it in a dryer, it is ready for use, thus obtaining the highly transparent TPX modified material. The temperature of the twin - screw is 195 - 200 °C.

[0086] 7) Weigh the following components by mass parts: including highly transparent modified TPX: 34 PHR, ethylene-vinyl acetate copolymer (7350): 35 PHR, olefin block copolymer (9530): 16 PHR, thermoplastic elastomer TPE (4003-85T): 15 PHR, wear-resistant agent (108P): 7.5 PHR, stearic acid (Ste1842): 0.3 PHR, zinc stearate (Znst): 1 PHR.

[0087] 8) Put all the components weighed in step 7) into a Banbury mixer for mixing. The mixing time is 8 - 10 minutes and the temperature is 115 - 120 °C.

[0088] 9) Weigh the following components by mass parts: odorless crosslinking agent (BIPB) 0.63 PHR, transparent blowing agent (CAP) 6.8 HR.

[0089] 10) Add all the components weighed in step 9) to the Banbury mixer for mixing. The mixing time is 5 - 7 minutes and the temperature is 120 - 125 °C.

[0090] 11) Granulate the mixture obtained in step 10). The granulation time is 9 - 11 minutes and the temperature of the granulator is 100 °C - 105 °C.

[0091] 12) Pour the particles obtained in step 11) into the required small foaming mold for foaming. The foaming ratio of the small foam is 1.9 - 1.95% (the temperature of the small foaming machine is 165 - 175 °C, the pressure is 150 - 170 kg / cm 2 , and the small foaming time of MD is 600 - 650 seconds);

[0092] Clean and store the small foam obtained in step 12) for 12 hours, then put it into an MD molding machine and heat for 420 seconds, and cool for 420 seconds (the temperature of the MD molding machine is 155 - 165 °C, and the cooling temperature is 11 - 17 °C) to obtain an ultra-light, high resilience, shock-absorbing, transparent EVA composite chemical foamed MD sole.

[0093] Example Two (MD)

[0094] The present invention provides an ultra-light, high resilience, shock-absorbing, transparent EVA composite chemical foamed sole material, which is obtained by foaming a highly transparent modified TPX composite material. The highly transparent modified TPX composite material includes the following components in mass parts:

[0095] High transparency modified TPX: 39 PHR, ethylene-vinyl acetate copolymer (7350M): 41 PHR, olefin block copolymer (9530): 8 PHR, thermoplastic elastomer TPE (4003-85T): 12 PHR, wear-resistant agent (108P): 6.5 PHR, stearic acid (Ste1842): 0.3 PHR, zinc stearate (Znst): 1 PHR, odorless crosslinking agent (BIPB): 0.68 PHR, transparent foaming agent (CAP): 6.2 PHR.

[0096] Preferably, the preparation method of the high transparency modified TPX comprises the following steps:

[0097] 1) Weigh the following components by parts by mass: high transparency copolymerized TPX MX021: 60 PHR, EVOH amorphous EV4405F: 40 PHR, stearic acid: 0.3 PHR.

[0098] 2) Add the high transparency TPX and stearic acid weighed in step 1) to the hopper of a twin-screw granulator for mixing and kneading, convey it to the homogenization area, and add EVOH at the side feeding port for homogenization.

[0099] Extrude the melt of the mixture homogenized in step 2) through the die head to form a continuous strip, then extrude, cool and pelletize it. After drying it by a dryer, it is ready for use. The temperature of the twin-screw is 230 - 235 °C.

[0100] 4) Weigh 70 PHR of the pellets produced in step 3) by parts by mass, ethylene propylene diene monomer (3745) 30 PHR, stearic acid 0.3 PHR.

[0101] 5) Add the pellets and stearic acid weighed in step 4) together to the hopper of a twin-screw granulator for mixing and kneading, convey it to the homogenization area, and add ethylene propylene diene monomer at the side feeding port for homogenization.

[0102] 6) Extrude the melt of the mixture homogenized in step 5) through the die head to form a continuous strip, then extrude, cool and pelletize it. After drying it by a dryer, it is ready for use, and the high transparency TPX modified material can be obtained. The temperature of the twin-screw is 195 - 200 °C.

[0103] 7) Weigh the following components by parts by mass: including high transparency modified TPX: 39 PHR, ethylene-vinyl acetate copolymer (7350M): 41 PHR, olefin block copolymer (9530): 8 PHR, thermoplastic elastomer TPE (4003-85T): 12 PHR, wear-resistant agent (108P): 6.5 PHR, stearic acid (Ste1842): 0.3 PHR, zinc stearate (Znst): 1 PHR.

[0104] 8) Put all the ingredients weighed in step 7) into a kneader for kneading. The kneading time is 8 - 10 minutes and the temperature is 115 - 120 °C;

[0105] 9) Weigh the following ingredients by mass parts: odorless crosslinking agent (BIPB) 0.68 PHR, transparent blowing agent (CAP) 6.2 HR.

[0106] 10) Add all the ingredients weighed in step 9) to a kneader for kneading. The kneading time is 5 - 7 minutes and the temperature is 120 - 125 °C;

[0107] 11) Granulate the mixture obtained in step 10). The granulation time is 9 - 11 minutes and the granulator temperature is 100 °C - 105 °C.

[0108] 12) Pour the particles obtained in step 11) into the required small foaming mold for foaming. The foaming ratio of the small foam is 1.9 - 1.95% (the temperature of the small foaming machine is 165 - 175 °C, the pressure is 150 - 170 kg / cm 2 , and the small foam MD foaming time is 600 - 650 seconds);

[0109] Clean and store the small foam obtained in step 12) for 12 hours, then put it into an MD molding machine and heat for 420 seconds, and cool for 420 seconds (the temperature of the MD molding machine is 155 - 165 °C, the cooling temperature is 11 - 17 °C), to obtain an ultra - light, high - resilience, shock - absorbing, transparent EVA composite chemical - foamed MD sole.

[0110] Example Three (MD)

[0111] The present invention provides an ultra - light, high - resilience, shock - absorbing, transparent EVA composite chemical - foamed sole material, which is obtained by foaming a highly transparent modified TPX composite material. The highly transparent modified TPX composite material comprises the following components in mass parts:

[0112] Highly transparent modified TPX: 45 PHR, ethylene - vinyl acetate copolymer (7350M): 42 PHR, olefin block copolymer (9530): 5 PHR, thermoplastic elastomer TPE (4003 - 85T): 8 PHR, wear - resistant agent (108P): 6 PHR, stearic acid (Ste1842): 0.3 PHR, zinc stearate (Znst): 1 PHR, odorless crosslinking agent (BIPB): 0.72 PHR, transparent blowing agent (CAP): 6.5 PHR

[0113] Preferably, the preparation method of the highly transparent modified TPX comprises the following steps:

[0114] 1) Weigh the following components by parts by mass: High-transparency copolymer TPX MX021: 60 PHR, EVOH amorphous EV4405F: 40 PHR, Stearic acid (STE1842): 0.3 PHR.

[0115] 2) Add the high-transparency TPX and stearic acid weighed in step 1) to the hopper of a twin-screw granulator for mixing and conveying to the homogenization area, and add EVOH at the side feeding port for homogenization.

[0116] 3) Extrude the homogenized mixture melt through the die head to form a continuous strip, then extrude, cool and pelletize. After drying in a dryer, it is ready for use. The temperature of the twin-screw is 230 - 235 °C.

[0117] 4) Weigh 70 PHR of the pellets produced in step 3), 30 PHR of ethylene propylene diene monomer (3745), and 0.3 PHR of stearic acid by parts by mass.

[0118] 5) Add the pellets and stearic acid weighed in step 4) together to the hopper of a twin-screw granulator for mixing and conveying to the homogenization area, and add ethylene propylene diene monomer at the side feeding port for homogenization.

[0119] 6) Extrude the homogenized mixture melt through the die head to form a continuous strip, then extrude, cool and pelletize. After drying in a dryer, it is ready for use, and thus a high-transparency TPX modified material can be obtained. The temperature of the twin-screw is 200 - 205 °C (195 - 200 °C).

[0120] 7) Weigh the following components by parts by mass: including high-transparency modified TPX (PMPMX021): 45 PHR, ethylene-vinyl acetate copolymer (7350M): 42 PHR, olefin block copolymer (9530): 5 PHR, thermoplastic elastomer TPE (4003 - 85T): 8 PHR, wear-resistant agent (108P): 6 PHR, stearic acid (Ste1842): 0.3 PHR, zinc stearate (Znst): 1 PHR.

[0121] 8) Put all the components weighed in step 7) into a mixer for mixing. The mixing time is 8 - 10 minutes and the temperature is 115 - 120 °C;

[0122] 9) Weigh the following components by parts by mass: odorless cross-linking agent (BIPB) 0.72 PHR, transparent foaming agent (CAP) 6.5 HR.

[0123] 10) Add all the components weighed in step 9) to the mixer for mixing. The mixing time is 5 - 7 minutes and the temperature is 120 - 125 °C;

[0124] 11) Granulate the mixture obtained in step 10), with the granulation time being 9 - 11 minutes and the granulator temperature being 100°C - 105°C.

[0125] 12) Pour the particles obtained in step 11) into the required small foaming mold for foaming, with the small foaming ratio being 1.9 - 1.95% (the small foaming machine temperature is 165 - 175°C, and the pressure is 150 - 170 kg / cm 2 , and the MD small foaming time is 600 - 650 seconds);

[0126] Clean and store the small foam obtained in step 12) for 12 hours, then put it into the MD molding machine to heat for 420 seconds and cool for 420 seconds (the MD molding machine temperature is 155 - 165°C, and the cooling temperature is 11 - 17°C), to obtain an ultra - light, high - resilience, shock - absorbing, transparent EVA composite chemical - foamed MD sole.

[0127] Comparative Example 1 (MD)

[0128] 1. Formula:

[0129] Polyolefin elastomer (8003): 63 PHR, maleic anhydride - grafted POE: 3 PHR, olefin block copolymer OBC: 12 PHR, ethylene - propylene - diene rubber (3092): 5 PHR, ethylene - vinyl acetate copolymer (7350M): 5 PHR, filler (talc powder): 4 PHR, wear - resistant agent: 6 PHR, stearic acid (Ste1842): 0.2 PHR, zinc stearate (Znst): 0.3 PHR, odorless cross - linking agent (BIPB): 0.6 PHR, zinc oxide: 1 PHR, foaming agent (AC6000H): 5.3 PHR, cross - linking aid (TAIC): 0.6 PHR

[0130] 2. Preparation process:

[0131] Extrude and granulate the above - weighed polyolefin elastomer and maleic anhydride - grafted POE after twin - screw modification; the preferred temperature for mixing is 135 - 140°C, and the preferred mixing time is 13 - 15 min.

[0132] Then add olefin block copolymer, ethylene - propylene - diene rubber, ethylene - vinyl acetate copolymer, filler, stearic acid, zinc stearate, zinc oxide, cross - linking aid, cross - linking agent, and foaming agent to the granulated material and mix and granulate again. The temperature for the second mixing is 125 - 130°C, and the second mixing time is 10 - 12 min. The foaming ratio is 1.75%, to obtain an extremely light - weight, wear - resistant, low - compression, high - resilience composite foamed material for sports shoe soles.

[0133] Comparative Example 2 (MD)

[0134] 1. Formula

[0135] Polyolefin elastomer (8402): 30 PHR, ethylene-vinyl acetate copolymer (26061): 50 PHR, SEBS (YH688): 10 PHR, methyl methacrylate copolymer (514D): 10 PHR, wear-resistant agent (108P): 8 PHR, stearic acid: 0.8 PHR, zinc stearate: 1 PHR, odorless crosslinking agent: 0.5 PHR, foaming agent (AC6000H): 3.5 PHR, oxidant: 1 PHR.

[0136] 2. Preparation process:

[0137] In the present invention, ethylene-vinyl acetate copolymer, ethylene-octene random copolymer, SEBS and ethylene-methacrylic acid copolymer are first mixed, and zinc oxide, stearic acid, zinc stearate and vinyl silicone oil wear-resistant agent are added when the temperature is raised to 75 - 85°C. Then, an odorless crosslinking agent BIPB and a foaming agent are added when the temperature is raised to 85 - 95°C. When the temperature is raised to 100 - 105°C, a mixed material is obtained.

[0138] In the present invention, the mixed material is pelletized to obtain pellets. The present invention preferably uses a pelletizer well-known to those skilled in the art for pelletizing; the temperatures of the first zone, second zone, third zone and fourth zone of the pelletizer are adjusted to 75°C, 80°C, 85°C and 90°C respectively. When pelletizing, the screw speed is adjusted to 40 - 50 revolutions per minute, and the cutting speed is adjusted to 15 - 20 revolutions per minute.

[0139] In the present invention, the pellets are vulcanized and foamed at 175°C for 660 seconds to obtain semi-finished products.

[0140] After obtaining the semi-finished products, the present invention allows the semi-finished products to stand and cool for 24 h and then hot presses them at 175°C for 420 seconds. The compression ratio during hot pressing is 1.5 - 1.6, and after cooling, a lightweight, extremely elastic and fatigue-resistant foamed material is obtained.

[0141] Comparative Example 3 (MD)

[0142] The market's extremely light composite foamed material includes the following components in parts by mass:

[0143] Polyolefin elastomer (8450): 20 PHR, ethylene-vinyl acetate (7470): 41.7 PHR, polyolefin block copolymer OBC (9107): 16.6 PHR, methyl methacrylate copolymer (514D): 16.7 PHR, ethylene-propylene-diene monomer rubber (626): 5 PHR, filler (talc powder): 3.3 PHR, wear-resistant agent (108P): 12 PHR, stearic acid: 0.5 PHR, zinc stearate: 1.5 PHR, odorless crosslinking agent: 0.57 PHR, foaming agent (AC6000H): 5.8 PHR, zinc oxide 2 PHR, crosslinking aid (TAIC): 0.58 PHR.

[0144] The preparation method of the market's extremely light composite foaming material includes the following steps:

[0145] 1) Weigh the following components by parts by mass: Olefin elastomer (8450): 20 PHR, Ethylene vinyl acetate (7470): 41.7 PHR, Polyolefin block copolymer OBC: 16.6 PHR, Methacrylic acid copolymer (514D): 16.7 PHR, Ethylene propylene diene monomer rubber (626): 5 PHR, Filler: 3.3 PHR, Antiwear agent: 12 PHR, Stearic acid: 0.5 PHR, Zinc stearate: 1.5 PHR, Zinc oxide: 2 PHR, Bridging aid: 0.58 PHR.

[0146] 2) Put all the components weighed in step 1) into a Banbury mixer for kneading. The kneading time is 8 - 10 minutes, and the temperature is 120 - 125 °C;

[0147] 3) Weigh the following components by parts by mass: Odorless bridging agent: 0.57 PHR, Blowing agent (AC6000H): 5.8 PHR.

[0148] 4) Add all the components weighed in step 3) to the Banbury mixer for kneading. The kneading time is 5 - 7 minutes, and the temperature is 120 - 125 °C;

[0149] 5) Granulate the mixture obtained in step 4). The granulation time is 9 - 11 minutes, and the granulator temperature is 100 °C - 105 °C.

[0150] 6) Pour the particles obtained in step 5) into the required small foaming mold for foaming. The foaming ratio of the small foam is 1.95 - 2.05% (the temperature of the small foaming machine is 165 - 175 °C, the pressure is 150 - 170 kg / cm 2 , and the MD small foaming time is 600 - 650 seconds);

[0151] Clean and store the small foam obtained in step 6) for 12 hours, then put it into the MD molding machine to heat for 420 seconds and cool for 420 seconds (the temperature of the MD molding machine is 155 - 165 °C, and the cooling temperature is 11 - 17 °C) to obtain the market's extremely light EVA composite chemical foaming MD sole.

[0152] Comparative Example Four (MD)

[0153] The market's traditional MD lightweight transparent composite material includes the following components in parts by mass:

[0154] Polyolefin elastomer (8150): 17 PHR, ethylene-vinyl acetate copolymer (7470): 50 PHR, olefin block copolymer (9107): 25 PHR, ethylene propylene diene monomer rubber (3092): 8 PHR, wear-resistant agent (108P): 6 PHR, stearic acid: 0.2 PHR, zinc stearate: 0.8 PHR, odorless crosslinking agent: 0.7 PHR, foaming agent: 4.8 PHR.

[0155] 1) Weigh the following components by parts by mass: including polyolefin elastomer: 17 PHR; ethylene-vinyl acetate copolymer: 50 PHR; olefin block copolymer: 25 PHR; ethylene propylene diene monomer rubber: 8 PHR; wear-resistant agent: 6 PHR; stearic acid: 0.2 PHR; zinc stearate: 0.8 PHR.

[0156] 2) Knead all the components weighed in step 1), the kneading time is 8 - 10 minutes, and the temperature is 95 - 105 °C;

[0157] 3) Weigh the following components by parts by mass: odorless crosslinking agent: 0.7 PHR, foaming agent: 4.8 PHR.

[0158] 4) Add all the components weighed in step 3) to the material kneaded in step 2) and knead, the kneading time is 5 - 7 minutes, and the temperature is 115 - 118 °C;

[0159] 5) Granulate the mixture obtained in step 4), the granulation time is 9 - 11 minutes, and the temperature is 100 °C - 105 °C.

[0160] 6) Pour the particles obtained in step 5) into the required small foaming mold for foaming (the temperature of the small foaming machine is 165 - 175 °C, the pressure is 150 - 170 kg / cm 2 , and the small foaming time of MD is 600 - 650 seconds);

[0161] Clean and store the small foam obtained in step 6) for 12 hours, then put it into the MD molding machine and heat for 420 seconds, and cool for 420 seconds (the temperature of the MD molding machine is 155 - 165 °C, and the cooling temperature is 11 - 17 °C), to obtain the traditional market transparent foamed MD sole.

[0162] Comparative Example 5

[0163] On the basis of Example 1, during the preparation, starting from step 7), the preparation of the product is carried out, and the highly transparent modified TPX is replaced with highly transparent TPX.

[0164] 1) Weigh the following components by parts by mass: including high transparency TPX (PMPMX021): 20.4 PHR, EVOH: 6.6 PHR, ethylene propylene diene monomer (3745): 7 PHR, ethylene-vinyl acetate copolymer (7350M): 35 PHR, olefin block copolymer (9530): 16 PHR, thermoplastic elastomer TPE (4003-85T): 15 PHR, wear-resistant agent (108P): 7.5 PHR, stearic acid (Ste1842): 0.3 PHR, zinc stearate (Znst): 1 PHR.

[0165] 2) Put all the components weighed in step 1) into a Banbury mixer for kneading. The kneading time is 25 - 30 minutes and the temperature is 230 - 235 °C.

[0166] 3) When the tensile and tear physical properties deteriorate, the reason is that the temperature is too high and some high molecular materials degrade.

[0167] 4) Weigh the following components by parts by mass: odorless cross-linking agent (BIPB) 0.63 PHR, transparent blowing agent (CAP) 6.8 HR, and there is a pungent smell and the material foams and cross-links in the Banbury mixer.

[0168] 5) The reason is that the temperature is too high. The blowing agent decomposes immediately when put into the Banbury mixer, producing a pungent smell. When the temperature exceeds 130 °C, the cross-linking agent (BIPB) begins to decompose and cross-linking occurs.

[0169] 6) If the temperature is set lower than 150 °C, neither TPX nor EVOH can be dispersed.

[0170] The following Table 1 shows the foaming ratio of the molded MD soles of the examples and comparative examples.

[0171] Table 1

[0172] Material Name Example 1 Example 2 Example 3 Comparative Example 1 Comparative Example 2 Comparative Example 3 Comparative Example 4 Foaming Ratio 1.92％ 1.92％ 1.92％ 1.75％ 2.05％ 1.95％ 1.75％

[0173] The physical properties of the MD secondary molded EVA foamed materials obtained from Examples 1, 2, 3 and Comparative Examples 1, 2, 3, 4 were tested. The results are shown in Table 2. The test conditions are temperature 23 ± 3 °C and humidity 65 ± 5%.

[0174] Table 2: Physical properties of the MD secondary molded EVA foamed materials of each example and comparative example

[0175]

[0176]

[0177] Example 4 (IP injection)

[0178] The present invention provides an ultra-light, high resilience, shock-absorbing, transparent EVA composite chemically foamed sole material, which is obtained by foaming a highly transparent modified TPX composite material. The highly transparent modified TPX composite material comprises the following components in parts by mass:

[0179] Highly transparent modified TPX: 40 PHR, ethylene-vinyl acetate copolymer (7470): 30 PHR, olefin block copolymer (9107): 15 PHR, thermoplastic elastomer TPE (4003-85T): 15 PHR, wear-resistant agent (108P): 7.5 PHR, stearic acid (Ste1842): 0.3 PHR, zinc stearate (Znst): 1 PHR, odorless cross-linking agent (BIPB): 0.7 PHR, transparent foaming agent (CAP): 4.8 PHR

[0180] Preferably, the preparation method of the highly transparent modified TPX comprises the following steps:

[0181] 1) Weigh the following components in parts by mass: highly transparent copolymerized TPX MX021: 60 PHR, EVOH amorphous EV4405F: 40 PHR, stearic acid: 0.3 PHR.

[0182] 2) Add the highly transparent TPX and stearic acid weighed in step 1) to the hopper of a twin-screw granulator for mixing and kneading, convey it to the homogenization area, and add EVOH at the side feeding port for homogenization.

[0183] Extrude the melt of the mixture homogenized in step 2) through the die head to form a continuous strip, then extrude, cool and pelletize it. After drying and baking in a dryer, it is ready for use. The temperature of the twin-screw is 230-235°C.

[0184] 4) Weigh 70 PHR of the pellets produced in step 3), 30 PHR of ethylene propylene diene monomer rubber, and 0.3 PHR of stearic acid in parts by mass.

[0185] 5) Add the pellets and stearic acid weighed in step 4) together to the hopper of a twin-screw granulator for mixing and kneading, convey it to the homogenization area, and add ethylene propylene diene monomer rubber at the side feeding port for homogenization.

[0186] 6) Extrude the melt of the mixture homogenized in step 5) through the die head to form a continuous strip, then extrude, cool and pelletize it. After drying and baking in a dryer, it is ready for use, and the highly transparent TPX modified material can be obtained. The temperature of the twin-screw is 200-205°C (195-200°C).

[0187] 7) Weigh the following components by parts by mass: including highly transparent modified TPX: 40 PHR, ethylene-vinyl acetate copolymer (7470): 30 PHR, olefin block copolymer (9107): 15 PHR, thermoplastic elastomer TPE (4003 - 85T): 15, wear-resistant agent (108P): 7.5 PHR, stearic acid (Ste1842): 0.3 PHR, zinc stearate (Znst): 1 PHR.

[0188] 8) Put all the components weighed in step 7) into a Banbury mixer for mixing. The mixing time is 8 - 10 minutes and the temperature is 115 - 120 °C.

[0189] 9) Weigh the following components by parts by mass: odorless crosslinking agent: 0.7 PHR, transparent foaming agent: 4.8 PHR.

[0190] 10) Add all the components weighed in step 9) to the Banbury mixer for mixing. The mixing time is 5 - 7 minutes and the temperature is 120 - 125 °C.

[0191] 11) Granulate the mixture obtained in step 10). The granulation time is 9 - 11 minutes and the temperature of the granulator is 100 °C - 105 °C.

[0192] 12) Pour the mixture particles obtained in step 11) into the hopper of an IP injection molding machine (the temperature of the injection molding machine is 175 - 180 °C, the clamping force of the machine is 120 bar, the injection pressure is 100 bar, the mold opening speed is 60%, and the four-section temperature of the injection gun is 100 °C, 102 °C, 104 °C, 106 °C) for injection foaming. The IP injection foaming time is 400 - 450 seconds and the foaming temperature is 175 °C - 180 °C, and an ultra-light, high resilience, shock-absorbing, transparent EVA composite chemical foamed material IP sole can be obtained.

[0193] Example Five (IP Injection)

[0194] The present invention provides an ultra-light, high resilience, shock-absorbing, transparent EVA composite chemical foamed sole material, which is prepared by foaming a highly transparent modified TPX composite material. The highly transparent modified TPX composite material comprises the following components in parts by mass:

[0195] Highly transparent modified TPX: 45 PHR, ethylene-vinyl acetate copolymer (7470): 41 PHR, olefin block copolymer (9107): 7 PHR, thermoplastic elastomer TPE (4003 - 85T): 7 PHR, wear-resistant agent (108P): 6.5 PHR, stearic acid (Ste1842): 0.3 PHR, zinc stearate (Znst): 1 PHR, odorless crosslinking agent (BIPB): 0.72 PHR, transparent foaming agent (CAP): 5.5 PHR.

[0196] Preferably, the preparation method of the highly transparent modified TPX comprises the following steps:

[0197] 1) Weigh the following components by parts by mass: highly transparent copolymerized TPX MX021: 60 PHR, EVOH amorphous EV4405F: 40 PHR, stearic acid: 0.3 PHR.

[0198] 2) Add the highly transparent TPX and stearic acid weighed in step 1) to the hopper of a twin-screw granulator for mixing and conveying to the homogenization area, and add EVOH at the side feeding port for homogenization.

[0199] 3) Extrude the homogenized mixture melt through the die head to form a continuous strip, then extrude, cool and pelletize. After drying in a dryer, it is ready for use. The temperature of the twin-screw is 230 - 235 °C.

[0200] 4) Weigh 70 PHR of the pellets produced in step 3), 30 PHR of ethylene propylene diene monomer rubber, and 0.3 PHR of stearic acid by parts by mass.

[0201] 5) Add the pellets and stearic acid weighed in step 4) together to the hopper of a twin-screw granulator for mixing and conveying to the homogenization area, and add ethylene propylene diene monomer rubber at the side feeding port for homogenization.

[0202] 6) Extrude the homogenized mixture melt through the die head to form a continuous strip, then extrude, cool and pelletize. After drying in a dryer, it is ready for use, and the highly transparent TPX modified material can be obtained. The temperature of the twin-screw is 195 - 200 °C.

[0203] 7) Weigh the following components by parts by mass: including highly transparent modified TPX: 45 PHR, ethylene-vinyl acetate copolymer: 41 PHR, olefin block copolymer: 7 PHR, thermoplastic elastomer TPE: 7 PHR, wear-resistant agent: 6.5 PHR, stearic acid: 0.3 PHR, zinc stearate: 1 PHR.

[0204] 8) Put all the components weighed in step 7) into a mixer for mixing. The mixing time is 8 - 10 minutes and the temperature is 115 - 120 °C;

[0205] 9) Weigh the following components by parts by mass: odorless cross-linking agent: 0.72 PHR, transparent blowing agent: 5.5 PHR.

[0206] 10) Add all the components weighed in step 9) to the mixer for mixing. The mixing time is 5 - 7 minutes and the temperature is 120 - 125 °C;

[0207] 11) Granulate the mixture obtained in step 10), with the granulation time being 9 - 11 minutes and the granulator temperature being 100°C - 105°C.

[0208] 12) Pour the mixture particles obtained in step 11) into the hopper of the IP injection molding machine (the injection molding machine temperature is 175 - 180°C, the machine clamping force is 120 bar, the injection pressure is 100 bar, the mold opening speed is 60%, and the four-section temperature of the injection gun is 100°C, 102°C, 104°C, 106°C) for injection foaming. The IP injection foaming time is 400 - 450 seconds, and the foaming temperature is 175°C - 180°C, to obtain an ultra-light, high resilience, shock-absorbing, transparent EVA composite chemical foamed material IP sole.

[0209] Example Six (IP Injection)

[0210] The present invention provides an ultra-light, high resilience, shock-absorbing, transparent EVA composite chemical foamed sole material, which is obtained by foaming a highly transparent modified TPX composite material. The highly transparent modified TPX composite material comprises the following components in parts by mass:

[0211] Highly transparent modified TPX: 50 PHR, ethylene-vinyl acetate copolymer (7474): 30 PHR, olefin block copolymer (9107): 10 PHR, thermoplastic elastomer TPE (4003 - 85T): 10 PHR, wear-resistant agent (108P): 6 PHR, stearic acid (Ste1842): 0.3 PHR, zinc stearate (Znst): 1 PHR, odorless cross-linking agent (BIPB): 0.75 PHR, transparent foaming agent (CAP): 6 PHR.

[0212] Preferably, the preparation method of the highly transparent modified TPX comprises the following steps:

[0213] 1) Weigh the following components in parts by mass: highly transparent copolymer TPX MX021: 60 PHR, EVOH amorphous EV4405F: 40 PHR, stearic acid: 0.3 PHR.

[0214] 2) Add the highly transparent TPX and stearic acid weighed in step 1) to the hopper of a twin-screw granulator for mixing and kneading, convey it to the homogenization area, and add EVOH at the side feeding port for homogenization.

[0215] 3) Extrude the homogenized mixture melt through the die head to form a continuous strip, then extrude and cool for pelletizing, and bake and dry it with a dryer for later use. The twin-screw temperature is 230 - 235°C.

[0216] 4) Weigh 70 PHR of the pellets produced in step 3), 30 PHR of ethylene propylene diene monomer rubber, and 0.3 PHR of stearic acid in parts by mass.

[0217] 5) Add the particles weighed in step 4) and stearic acid together into the hopper of the twin-screw granulator for mixing and conveying to the homogenization area, and add ethylene propylene diene monomer rubber at the side feeding port for homogenization.

[0218] 6) Extrude the homogenized mixture melt through the die head to form a continuous strip, then extrude, cool and pelletize. After drying by a dryer and baking for use, a highly transparent TPX modified material can be obtained. The temperature of the twin-screw is 195 - 200 °C.

[0219] 7) Weigh the following components by mass parts: including highly transparent modified TPX: 50 PHR, ethylene-vinyl acetate copolymer: 30 PHR, olefin block copolymer: 10 PHR, thermoplastic elastomer TPE: 10, wear-resistant agent: 6 PHR, stearic acid: 0.3 PHR, zinc stearate: 1 PHR, odorless crosslinking agent: 0.75 PHR, transparent foaming agent: 6 PHR.

[0220] 8) Put all the components weighed in step 7) into a kneader for mixing. The mixing time is 8 - 10 minutes and the temperature is 115 - 120 °C;

[0221] 9) Weigh the following components by mass parts: odorless crosslinking agent: 0.75 PHR, transparent foaming agent: 6 PHR.

[0222] 10) Add all the components weighed in step 9) into a kneader for mixing. The mixing time is 5 - 7 minutes and the temperature is 120 - 125 °C;

[0223] 11) Granulate the mixture obtained in step 10). The granulation time is 9 - 11 minutes and the temperature of the granulator is 100 °C - 105 °C.

[0224] 12) Put the mixture obtained in step 11) into the IP injection molding machine hopper (the temperature of the injection molding machine is 175 - 180 °C, the clamping force of the machine is 120 bar, the injection pressure is 100 bar, the mold opening speed is 60%, and the four-section temperature of the injection gun is 100 °C, 102 °C, 104 °C, 106 °C) for injection and foaming. The IP injection foaming time is 400 - 450 seconds and the foaming temperature is 175 °C - 180 °C, and an ultra-light, high-elasticity, shock-absorbing and transparent EVA composite chemical foaming material IP sole can be obtained.

[0225] Comparative Example 6 (IP injection)

[0226] The market light IP foaming composite material includes the following components by mass parts:

[0227] Ethylene-vinyl acetate copolymer: 45 PHR, olefin block copolymer modified material: 23 PHR, polyolefin elastomer: 23 PHR, ethylene propylene diene monomer rubber: 9 PHR, wear-resistant agent: 9 PHR, filler: 1.5 PHR, stearic acid: 0.5 PHR, zinc stearate: 0.7 PHR, zinc oxide: 1.3 PHR, odorless crosslinking agent: 0.7 PHR, AC6000H foaming agent: 4.5 PHR

[0228] 1) Weigh the following components by parts by mass: including polyolefin elastomer: 20 PHR; ethylene-vinyl acetate copolymer: 58 PHR; olefin block copolymer: 22 PHR; ethylene propylene diene monomer rubber: 8 PHR; wear-resistant agent: 6 PHR; stearic acid: 0.5 PHR; zinc stearate: 0.8 PHR.

[0229] 2) Knead all the components weighed in step 1), the kneading time is 8 - 10 minutes, and the temperature is 95 - 105 °C;

[0230] 3) Weigh the following components by parts by mass: odorless crosslinking agent: 0.65 PHR, foaming agent: 4.5 PHR.

[0231] 4) Add all the components weighed in step 3) to the material after kneading in step 2) and knead, the kneading time is 5 - 7 minutes, and the temperature is 115 - 118 °C;

[0232] 5) Granulate the mixture obtained in step 4), the granulation time is 9 - 11 minutes, and the temperature is 100 °C - 105 °C.

[0233] 6) Put the mixture obtained in step 5) into the hopper of the IP injection molding machine (the temperature of the injection molding machine is 175 - 180 °C, the clamping force of the machine is 120 bar, the injection pressure is 90 bar, the mold opening speed is 60%, and the four-section temperature of the injection gun is 84 °C, 86 °C, 88 °C, 90 °C) for injection foaming, the IP injection foaming time is 400 - 450 seconds, and the foaming temperature is 175 °C - 180 °C to obtain a lightweight transparent foamed IP sole.

[0234] Comparative Example Seven (IP injection)

[0235] The market lightweight transparent composite material includes the following components by parts by mass:

[0236] Polyolefin elastomer: 20 PHR, ethylene-vinyl acetate copolymer: 58 PHR, olefin block copolymer: 22 PHR, ethylene propylene diene monomer rubber: 8 PHR, wear-resistant agent: 6 PHR, stearic acid: 0.5 PHR, zinc stearate: 0.8 PHR, odorless crosslinking agent: 0.65 PHR, transparent foaming agent: 4.5 PHR

[0237] 1) Weigh the following components by parts by mass: including polyolefin elastomer: 20 PHR; ethylene-vinyl acetate copolymer: 58 PHR; olefin block copolymer: 22 PHR; ethylene propylene diene monomer rubber: 8 PHR; wear-resistant agent: 6 PHR; stearic acid: 0.5 PHR; zinc stearate: 0.8 PHR.

[0238] 2) Knead all the components weighed in step 1), the kneading time is 8 - 10 minutes, and the temperature is 95 - 105 °C;

[0239] 3) Weigh the following components by parts by mass: odorless cross-linking agent: 0.65 PHR, foaming agent: 4.5 PHR.

[0240] 4) Add all the components weighed in step 3) to the material obtained after kneading in step 2) and knead, the kneading time is 5 - 7 minutes, and the temperature is 115 - 118 °C;

[0241] 5) Granulate the mixture obtained in step 4), the granulation time is 9 - 11 minutes, and the temperature is 100 °C - 105 °C.

[0242] 6) Put the mixture obtained in step 5) into the hopper of the IP injection molding machine (the temperature of the injection molding machine is 175 - 180 °C, the clamping force of the machine is 120 bar, the injection pressure is 90 bar, the mold opening speed is 60%, and the four-section temperature of the injection gun is 84 °C, 86 °C, 88 °C, 90 °C) for injection foaming. The IP injection foaming time is 400 - 450 seconds, and the foaming temperature is 175 °C - 180 °C to obtain a transparent foamed IP sole.

[0243] The following Table 3 shows the foaming ratios of the soles of the IP one-shot process in the examples and comparative examples:

[0244] Table 3

[0245] Material Name Example 4 Example 5 Example 6 Comparative Example 6 Comparative Example 7 Foaming Ratio 1.75％ 1.75％ 1.75％ 1.75％ 1.55％

[0246] For the IP one-shot EVA foamed materials obtained in Examples 4, 5, 6 and Comparative Examples 5, 6, physical property tests were carried out. The results are shown in Table 4, and the test conditions are a temperature of 23 ± 3 °C and a humidity of 65 ± 5%.

[0247] Table 4: Physical Properties of EVA Foamed Materials in Each Example and Comparative Example

[0248]

[0249] In each embodiment of the present invention, a highly transparent modified TPX composite material is added, and in the comparative examples, conventional polyolefin elastomers, polyolefin modified materials, acrylate copolymers, etc. are added. Among them, Examples 1, 2, and 3 and Comparative Examples 1, 2, 3, and 4 are MD secondary processes, and Examples 4, 5, and 6 and Comparative Examples 5 and 6 are IP primary injection processes. It can be seen from the test data in Table 2 and Table 4 that regardless of the IP primary injection process or the MD secondary die pressing process, the shock absorption performance, specific gravity, energy feedback, resilience performance, and transparency of each embodiment are significantly better than those of the comparative examples, and the data of each embodiment can meet the national standards.

[0250] The above are only the preferred embodiments of the present invention. It should be noted that for those of ordinary skill in the art, without departing from the principle of the present invention, several improvements and refinements can be made, and these improvements and refinements should also be regarded as the protection scope of the present invention.

Claims

1. A super-light, high-resilience, shock-absorbing transparent EVA composite chemically foamed material, characterized in that, It comprises raw materials in the following parts by mass: High transparency modified TPX: 30 - 60 parts, ethylene-vinyl acetate copolymer: 30 - 50 parts, thermoplastic elastomer TPE: 7 - 25 parts, olefin block copolymer: 5 - 16 parts, wear-resistant agent: 5 - 10 parts, stearic acid: 0.2 - 0.5 part, zinc stearate: 0.2 - 1 part, odorless crosslinking agent: 0.3 - 1.5 parts, transparent blowing agent: 3.5 - 8 parts; The high transparency modified TPX is prepared from high transparency TPX, EVOH, ethylene propylene diene monomer rubber and stearic acid.

2. The foamed material according to claim 1, wherein The preparation raw materials of the high transparency modified TPX include: 50 - 70 parts by mass of high transparency TPX; 35 - 45 parts by mass of EVOH; 15 - 25 parts by mass of ethylene propylene diene monomer rubber; 0.5 - 0.8 part by mass of stearic acid.

3. The foamed material according to claim 1, characterized in that, The preparation method of the high transparency modified TPX comprises the following steps: a) Knead high transparency TPX and stearic acid, then add EVOH for homogenization to obtain a mixture melt; Extrude the mixture melt with a twin-screw extruder and then dry it to obtain a mixture; b) Knead the mixture with stearic acid, then add ethylene propylene diene monomer rubber for homogenization to obtain a mixture melt; Extrude the mixture melt and then dry it with a twin-screw extruder to obtain high transparency modified TPX.

4. The foamed material according to claim 1, wherein, The high transparency TPX is selected from one or more of high transparency TPX with models PMPMX001, PMPMX002, PMP MX004, PMPMX021, PMP MX022; The EVOH is selected from one or more of EVOH with models EV2904F, EV2951F, EV3251F, EV3851F, EV4405F, EV4451F; The ethylene propylene diene monomer rubber is selected from one or more of ethylene propylene diene monomer rubber with models 3745, 3760, 3762; 5. The foamed material according to claim 1, characterized in that, The ethylene vinyl acetate copolymer is selected from one or several of ethylene vinyl acetate copolymers with models EVA7470M, EVA7350M, EVA7360M, EVA40W; 6. The foamed material according to claim 1, wherein, The olefin block copolymer is selected from one or several of olefin block copolymers with models OBC9107, OBC9007, OBC9500, OBC9530; 7. The foamed material according to claim 1, wherein The thermoplastic elastomer TPE is selected from one or several of medium thermoplastic elastomer TPE with models T-Blend pellet 4008 - 80T, 4008 - 60N, 4003 - 85T; 8. The foamed material according to claim 1, characterized in that, The wear-resistant agent is a pre-dispersed silicone masterbatch wear-resistant agent.

9. A preparation method of the ultra-light high-resilience shock-absorbing transparent EVA composite chemical foaming material according to any one of claims 1 to 8, characterized in that, It comprises the following steps: A) Knead high transparency modified TPX, ethylene-vinyl acetate copolymer, thermoplastic elastomer TPE, olefin block copolymer, wear-resistant agent, stearic acid and zinc stearate and then pelletize to obtain a mixture; B) Knead the mixture, odorless crosslinking agent and transparent blowing agent and then pelletize to obtain a material to be foamed; C) Foam the material to be foamed to obtain a foamed material.

10. A sole, characterized in that, It is prepared from the ultra-light high resilience shock-absorbing transparent EVA composite chemical foamed material according to any one of claims 1 - 8.

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