High-wear-resistance photochromic sole material and preparation method thereof

Abstract

The invention relates to the technical field of footwear products, in particular to a high-wear-resistance photochromic sole material and a preparation method thereof, and the high-wear-resistance photochromic sole material comprises the following raw materials in parts by mass: 50-100 parts of a rubber composition, 30-40 parts of an additive, 20-25 parts of silica sol, 1-3 parts of a silane coupling agent, 0.5-1 part of stearic acid, 0.5-1 part of a vulcanizing agent and 0.1-3 parts of a photochromic agent. The high-wear-resistance photosensitive color-changing sole material disclosed by the invention has relatively good wear resistance, mechanical property and self-repairing property.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of footwear products, in particular to a high-wear-resistance light-induced color-changing shoe sole material and a preparation method thereof. BACKGROUND

[0002] In the process of continuous iteration of footwear materials, the dual demands of consumers for product functionality and aesthetic value are driving the industry to explore deep technical waters. Traditional shoe sole materials have long been faced with the contradiction between "wear resistance" and "environmental adaptability": natural rubber has good elasticity, but is prone to cracking in complex terrain; synthetic rubber, after improving wear resistance through carbonization and vulcanization processes, increases the density of the material, leading to excessive weight of the shoe; and light-weight foaming materials such as EVA and TPU can meet the lightweight needs of daily wear, but they have shortcomings such as insufficient tear resistance and poor weather resistance in outdoor scenarios. At the same time, consumers' demand for personalized expression of footwear products is becoming increasingly strong, and static colors are no longer sufficient to meet the young generation's pursuit of dynamic visual effects. Against this background, the development of high-wear-resistance light-induced color-changing shoe sole materials has emerged as the times require, which, through the cross-fusion of material science, photochemistry, and surface engineering, opens up a new path for the footwear industry to achieve coordinated innovation in functionality and aesthetics.

[0003] The core principle of light-induced color-changing technology is based on the reversible structural transformation of photochromic molecules. When specific wavelengths of ultraviolet light are irradiated, the electron transition in the molecule causes a change in the conjugated system, resulting in a shift in the material's absorption spectrum, which in turn causes a visible color change. This property has been applied in the early stages to fields such as anti-counterfeiting labels and smart window films, but due to issues such as insufficient material durability and slow color-changing response, it has always failed to break through the industrial application threshold. For example, patent CN115746367B discloses a "light-induced color-changing fashion rubber boot and its preparation method" using resin, antioxidant, auxiliary antioxidant, light stabilizer, and photochromic agent as raw materials. The boot has good stability, high long-term light transmittance, and good light-induced color-changing effect, but the disclosed document does not add wear-resistant additives or modify the base resin for wear resistance, leaving room for improvement in wear resistance.

[0004] Therefore, there is an urgent need to develop a rubber shoe sole that combines wear resistance and color-changing ability. SUMMARY

[0005] The purpose of the present application is to provide a high-wear-resistance light-induced color-changing shoe sole material and a preparation method thereof to solve the problem of poor wear resistance of color-changing shoe soles.

[0006] To achieve the above-mentioned purpose, the present application adopts the following technical solutions: The application provides a high-wear-resistance photosensitive color-changing shoe sole material, which comprises the following raw materials in mass parts: 50-100 parts of a rubber composition, 30-40 parts of an additive aid, 20-25 parts of a silica sol, 1-3 parts of a silane coupling agent, 0.5-1 part of stearic acid, 0.5-1 part of a vulcanizing agent and 0.1-3 parts of a photochromic agent.

[0007] With the change of people's quality of life, people's appearance requirements are gradually improved, and single-color shoe soles have been difficult to meet people's visual requirements of unique and three-dimensional appearance, so color-changing shoe soles gradually enter the market. The preparation of the current color-changing shoe soles is only to add some photochromic or thermochromic color-changing powders, however, the color-changing powders will fall off in the daily wear process of the shoe soles, and finally the color-changing performance will be poor.

[0008] The high-wear-resistance photosensitive color-changing shoe sole material is prepared by using the specific mass parts of the rubber composition, the additive aid, the silica sol, the silane coupling agent, the stearic acid, the vulcanizing agent and the photochromic agent as raw materials, and the high-wear-resistance photosensitive color-changing shoe sole material can not only make the shoe sole have good and stable photochromic ability, but also has excellent wear resistance.

[0009] In some embodiments, the rubber composition comprises modified ethylene-propylene-diene rubber, butadiene rubber and natural rubber.

[0010] The three kinds of rubber are cooperated to improve the wear resistance, anti-skid ability and elasticity of the rubber.

[0011] In some embodiments, the mass ratio of the modified ethylene-propylene-diene rubber, the butadiene rubber and the natural rubber is (1.2-1.4):(1-2):1.

[0012] Preferably, the mass ratio of the modified ethylene-propylene-diene rubber, the butadiene rubber and the natural rubber is 1.3:1.5:1.

[0013] The mass ratio of the modified ethylene-propylene-diene rubber, the butadiene rubber and the natural rubber is regulated to improve the wear resistance of the shoe sole, and the hardness is prevented from being too high to cause the comfort to be reduced.

[0014] In some embodiments, the preparation method of the modified ethylene-propylene-diene rubber comprises the following steps: (1) 4-maleimide phenol, 1,3,5-tris(4-aminophenoxy)benzene and polyformaldehyde are mixed, 1,4-dioxane is added to stir and disperse uniformly, then the temperature is increased to reflux to stir for 3-4 days, after the end, the temperature is cooled to room temperature, n-hexane is added until no precipitate is generated, then the pressure is reduced to concentrate, tetrahydrofuran and n-hexane are used for recrystallization, then filtration and drying are carried out to obtain a crosslinking agent; (2) 4-penten-1-ol, 4-ethoxyphenol and pyridine are mixed into dichloromethane, then 2,5-furandicarboxylic dichloride and DMAP are added, constant temperature stirring is carried out at room temperature for 20-30 h, after the reaction is completed, dilute hydrochloric acid is added, stirring is carried out for 0.5-1 h, after extraction, the organic phase is dried and concentrated, and column chromatography purification is carried out to obtain the compound shown in formula I (I); (3) after the ternary ethylene-propylene rubber is melted, an initiator, the compound shown in formula I in step (2) and the crosslinking agent in step (1) are added, and the mixing is carried out for 5-10 min to obtain a rubber compound, the rubber compound is placed in a hot press, and after being taken out, annealing is carried out to obtain the modified ternary ethylene-propylene rubber.

[0015] The conventional ternary ethylene-propylene rubber has poor wear resistance and poor application range.

[0016] The modified ternary ethylene-propylene rubber can not only improve the wear resistance of the shoe sole, but also improve the self-repairing ability of the shoe sole and the service life of the shoe sole, and the reason may be that firstly, the crosslinking agent is self-made, the crosslinking agent has a three-branch structure, and the branch structure contains maleimide, the double bond structure can be crosslinked with the double bond in the ternary ethylene-propylene rubber to form a stable three-dimensional network structure, thereby improving the wear resistance of the shoe sole; in addition, the reversible crosslinking structure formed by the furan structure and the maleimide endows the shoe sole with self-repairing ability and improves the stability of the color-changing material therein.

[0017] In some embodiments, the molar ratio of the 4-maleimide phenol and 1,3,5-tris(4-aminophenoxy)benzene is (3-3.5):1.

[0018] By adjusting the molar ratio of the 4-maleimide phenol and 1,3,5-tris(4-aminophenoxy)benzene, the crosslinking agent has a three-branch structure, the rubber crosslinking agent is improved, and the self-repairing ability is improved.

[0019] Preferably, the molar ratio of the 4-maleimide phenol and 1,3,5-tris(4-aminophenoxy)benzene is 3.2:1.

[0020] In some embodiments, the molar ratio of the 4-penten-1-ol, 4-ethoxyphenol and 2,5-furandicarboxylic dichloride is (0.9-1.1):(0.9-1.1):1.

[0021] Preferably, the molar ratio of the 4-penten-1-ol, 4-ethoxyphenol and 2,5-furandicarboxylic dichloride is 1:1:1.

[0022] In some embodiments, in step (3), the mass ratio of the ethylene-propylene-diene rubber, the compound of formula I and the crosslinking agent is 1: (0.1-0.3): (0.01-0.05).

[0023] Preferably, in step (3), the mass ratio of the ethylene-propylene-diene rubber, the compound of formula I and the crosslinking agent is 1:0.2:0.03.

[0024] In some embodiments, the additive is white carbon black.

[0025] In some embodiments, the vulcanizing agent is dicumyl peroxide.

[0026] Another aspect of the present application provides a preparation method of a high-wear-resistance light-induced color-changing shoe sole material, comprising the following steps: mixing a rubber composition, adding an additive, silica sol, a silane coupling agent, stearic acid, a vulcanizing agent and a light-induced color-changing agent, uniformly mixing and vulcanizing to obtain the high-wear-resistance light-induced color-changing shoe sole material.

[0027] Compared with the prior art, the present application has the following beneficial effects: (1) The high-wear-resistance light-induced color-changing shoe sole material of the present application is prepared by using a specific mass fraction of rubber composition, additive, silica sol, silane coupling agent, stearic acid, vulcanizing agent and light-induced color-changing agent as raw materials. The high-wear-resistance light-induced color-changing shoe sole material of the present application not only has good and stable light-induced color-changing ability, but also has excellent wear resistance.

[0028] (2) The present application can improve the wear resistance of the shoe sole by adjusting the mass ratio of the modified ethylene-propylene-diene rubber, butadiene rubber and natural rubber, and can prevent the hardness from being too high to cause a decrease in comfort.

[0029] (3) The modified ethylene-propylene-diene rubber of the present application not only improves the wear resistance of the shoe sole, but also improves the self-repairing ability of the shoe sole to improve the service life of the shoe sole. The reason may be that: first, the present application self-prepares a crosslinking agent, which has a three-branch structure and contains maleimide in the branch structure. The double bond structure can be crosslinked with the double bond in the ethylene-propylene-diene rubber to form a stable three-dimensional network structure, thereby improving the wear resistance of the shoe sole. In addition, the reversible crosslinking structure formed by the furan structure and the maleimide endows the shoe sole with self-repairing ability and improves the stability of the color-changing material therein. DETAILED DESCRIPTION

[0030] The technical solution of the present invention will be clearly and completely described below with reference to specific embodiments. However, those skilled in the art will understand that the embodiments described below are some embodiments of the present invention, but not all embodiments, and are only used to illustrate the present invention, and should not be regarded as limiting the scope of the present invention. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention. Where specific conditions are not specified in the embodiments, conventional conditions or conditions recommended by the manufacturer shall be followed. Where the manufacturers of reagents or instruments are not specified, they are all conventional products that can be purchased commercially.

[0031] Unless otherwise specified, the post-processing operations described below, such as "concentration", "stirring", "recrystallization", "reflux", "filtration", "drying", "column chromatography", "extraction", "hot pressing", "mixing", and "annealing", can be selected by those skilled in the art based on actual conditions, and are not further limited.

[0032] In the following embodiments, EPDM rubber was purchased from Shandong Guanxiang New Material Co., Ltd.; butadiene rubber was purchased from Jining Fangyu Chemical Co., Ltd.; silica sol was purchased from Shanghai Hongzhuang Chemical Technology Co., Ltd.; and photochromic agent was purchased from Guangzhou Jingcai Pigment Technology Co., Ltd., model RP Photochromic Violet UVC P-Violet (based on a 100% mass percentage, comprising the following components: 32-36% melamine resin, 6.5-8% styrene-maleic anhydride random copolymer, 50-60% 1,2-dimethyl-4-(1-phenylethyl)benzene and 2.6-4% 1,3,3-trimethylindoline-6'-(1-piperidinyl)spirophoxazine).

[0033] Preparation Example 1 The preparation method of modified EPDM rubber includes the following steps: (1) Mix 0.32 mol 4-maleimide phenol, 0.1 mol 1,3,5-tris(4-aminophenoxy)benzene and 19 g paraformaldehyde, add 700 ml 1,4-dioxane and stir to disperse evenly, then heat to reflux and stir for 3 days. After the end, cool to room temperature and add n-hexane until no more precipitate is formed. Then concentrate under reduced pressure, recrystallize by tetrahydrofuran and n-hexane, then filter and dry to obtain crosslinking agent; (2) 0.1 mol of 4-penten-1-ol, 0.1 mol of 4-ethoxyphenol and 0.3 mol of pyridine were mixed and added to 800 mL of dichloromethane, followed by 0.1 mol of 2,5-furandicarboxylic acid chloride and 0.005 mol of DMAP. The mixture was stirred at room temperature for 25 h. After the reaction, 1 N hydrochloric acid solution was added to adjust the pH to 7, and the mixture was stirred for 0.7 h. The organic phase was extracted, dried and concentrated, and purified by column chromatography to obtain the compound shown in Formula I. (Ⅰ); 1 H NMR (300 MHz, DMSO-d6) δ 7.56 (d, J = 5.6 Hz, 1H), 7.41 (d, J =5.6 Hz, 1H), 7.19 – 7.10 (m, 2H), 6.90 – 6.80 (m, 2H), 5.73 (tt, J = 17.1,6.8 Hz, 1H), 5.04 (dddt, J = 44.3, 17.1, 2.2, 1.1 Hz, 2H), 4.10 (t, J = 6.8Hz, 2H), 3.80 (s, 3H), 2.08 (tdq, J = 8.4, 6.7, 0.9 Hz, 2H), 1.86 – 1.65 (m,2H); (3) After melting 50g of EPDM rubber, add 0.05g of DCP, 10g of the compound shown in Formula I in step (2) and 1.5g of the crosslinking agent in step (1), and mix at 160℃ for 7min to obtain a compound. Place the compound in a hot press (20MPa, 150℃ for 30min), remove and anneal to obtain modified EPDM rubber.

[0034] Preparation Example 2 The preparation method of modified EPDM rubber is the same as that in Preparation Example 1, except that equimolar amounts of 1,3-bis(4'-aminophenoxy)benzene are used instead of 1,3,5-tris(4-aminophenoxy)benzene.

[0035] Preparation Example 3 The preparation method of modified EPDM rubber is the same as that in Preparation Example 1, except that equimolar 4-penten-1-ol is used instead of 4-ethoxyphenol.

[0036] Preparation Example 4 The preparation method of modified EPDM rubber is the same as that in preparation example 1, except that in step (3), the crosslinking agent is 4g.

[0037] Example 1 A highly wear-resistant photosensitive color-changing shoe sole material comprises the following raw materials in parts by weight: 80 parts rubber composition, 35 parts silica, 23 parts silica sol, 2 parts bis(triethoxysilylpropyl) disulfide, 0.7 parts stearic acid, 0.7 parts sulfur and 2 parts photochromic agent.

[0038] The rubber composition includes modified ethylene propylene diene rubber, butadiene rubber, and natural rubber in a mass ratio of 1.3:1.5:1. The modified ethylene propylene diene rubber is prepared in Preparation Example 1.

[0039] A preparation method of a high-wear-resistance light-sensitive color-changing shoe sole material includes the following steps: mixing a rubber composition (1.5 h at 75 °C), adding white carbon black, silica sol, bis(triethoxysilylpropyl) disulfide, stearic acid, sulfur, and a light-sensitive color-changing agent, and uniformly mixing to perform vulcanization treatment (50 min at 145 °C) to obtain the high-wear-resistance light-sensitive color-changing shoe sole material.

[0040] Example 2 A high-wear-resistance light-sensitive color-changing shoe sole material includes the following ingredients in mass parts: 50 parts of a rubber composition, 30 parts of white carbon black, 20 parts of silica sol, 1 part of bis(triethoxysilylpropyl) disulfide, 0.5 part of stearic acid, 0.5 part of sulfur, and 0.1 part of a light-sensitive color-changing agent.

[0041] The rubber composition includes modified ethylene propylene diene rubber, butadiene rubber, and natural rubber in a mass ratio of 1.2:1:1. The modified ethylene propylene diene rubber is prepared in Preparation Example 1.

[0042] A preparation method of a high-wear-resistance light-sensitive color-changing shoe sole material includes the following steps: mixing a rubber composition (1.5 h at 75 °C), adding white carbon black, silica sol, bis(triethoxysilylpropyl) disulfide, stearic acid, sulfur, and a light-sensitive color-changing agent, and uniformly mixing to perform vulcanization treatment (50 min at 145 °C) to obtain the high-wear-resistance light-sensitive color-changing shoe sole material.

[0043] Example 3 A high-wear-resistance light-sensitive color-changing shoe sole material includes the following ingredients in mass parts: 100 parts of a rubber composition, 40 parts of white carbon black, 25 parts of silica sol, 3 parts of bis(triethoxysilylpropyl) disulfide, 1 part of stearic acid, 1 part of sulfur, and 3 parts of a light-sensitive color-changing agent.

[0044] The rubber composition includes modified ethylene propylene diene rubber, butadiene rubber, and natural rubber in a mass ratio of 1.4:2:1. The modified ethylene propylene diene rubber is prepared in Preparation Example 1.

[0045] A preparation method of a high-wear-resistance light-sensitive color-changing shoe sole material includes the following steps: mixing a rubber composition (1.5 h at 75 °C), adding white carbon black, silica sol, bis(triethoxysilylpropyl) disulfide, stearic acid, sulfur, and a light-sensitive color-changing agent, and uniformly mixing to perform vulcanization treatment (50 min at 145 °C) to obtain the high-wear-resistance light-sensitive color-changing shoe sole material.

[0046] Example 4 A high wear-resistant photosensitive color-changing sole material and a preparation method thereof, the specific implementation manner is the same as that of example 1, except that the modified ternary ethylene-propylene rubber is prepared from preparation example 2.

[0047] Example 5 A high wear-resistant photosensitive color-changing sole material and a preparation method thereof, the specific implementation manner is the same as that of example 1, except that the modified ternary ethylene-propylene rubber is prepared from preparation example 3.

[0048] Example 6 A high wear-resistant photosensitive color-changing sole material and a preparation method thereof, the specific implementation manner is the same as that of example 1, except that the modified ternary ethylene-propylene rubber is prepared from preparation example 4.

[0049] Example 7 A high wear-resistant photosensitive color-changing sole material and a preparation method thereof, the specific implementation manner is the same as that of example 1, except that the rubber composition includes modified ternary ethylene-propylene rubber, butadiene rubber and natural rubber in a mass ratio of 1:2:1.

[0050] Comparative Example 1 A high wear-resistant photosensitive color-changing sole material and a preparation method thereof, the specific implementation manner is the same as that of example 1, except that equal mass parts of ternary ethylene-propylene rubber are used instead of modified ternary ethylene-propylene rubber.

[0051] Performance test: (1) Tensile strength and tear strength: tested according to DIN53543; (2) Self-repairing ability: a 1mm deep and 5mm long crack is made on the surface of the sample with a blade, and the sample is left to stand for 24h at 23±2℃ and a relative humidity of 50±5%; the tensile strength after repair is tested, and the self-repairing efficiency = (tensile strength after repair / tensile strength before repair) x 100%; (3) Wear rate: the Taber abrasion amount is tested using a U.S. Taber rotary abrasion tester.

[0052] Table 1

[0053] According to the data in Table 1, the high wear-resistant photosensitive color-changing shoe sole materials of Examples 1-3 have good mechanical properties, wear resistance and self-repairing properties; in Example 4, 1,3-bis(4'-aminophenoxy) benzene is used instead of 1,3,5-tris(4-aminophenoxy) benzene, the crosslinking density of the modified EPDM rubber decreases, resulting in the decrease of the mechanical properties and wear resistance of the shoe sole material, and the self-repairing property is slightly improved; in Example 5, equimolar 4-penten-1-ol is used instead of 4-ethoxyphenol, resulting in the decrease of the self-repairing efficiency of the shoe sole material, but the mechanical properties and wear resistance are improved; in Example 6, the amount of the crosslinking agent is changed, resulting in the decrease of the self-repairing efficiency of the shoe sole material, but the mechanical properties and wear resistance are improved; in Example 7, the mass ratio of the modified EPDM rubber, butadiene rubber and natural rubber is changed, resulting in the decrease of the mechanical properties, wear resistance and self-repairing property of the color-changing shoe sole material; in Comparative Example 1, equimolar EPDM rubber is used instead of the modified EPDM rubber, resulting in the decrease of the mechanical properties, wear resistance and self-repairing property of the color-changing shoe sole material.

[0054] The above description is only the preferred embodiment of the present application, and does not limit the present application in any form. Although the present application has been disclosed as above with the preferred embodiment, it is not intended to limit the present application. Any person skilled in the art can make some changes or modifications to the above disclosed technical content without departing from the scope of the technical solution of the present application, and any simple modification, equivalent change and modification of the above embodiment according to the technical essence of the present application are still within the scope of the technical solution of the present application.

Claims

1. A high abrasion resistant, photosensitive, color-changing shoe sole material, characterized by, The rubber composition comprises 50-100 parts of rubber composition, 30-40 parts of additive aid, 20-25 parts of silica sol, 1-3 parts of silane coupling agent, 0.5-1 part of stearic acid, 0.5-1 part of vulcanizing agent and 0.1-3 parts of photochromic agent.

2. A high abrasion resistant, photochromic shoe sole material according to claim 1, wherein, The rubber composition comprises modified ethylene-propylene-diene rubber, butadiene rubber and natural rubber.

3. A high abrasion resistant, photochromic shoe sole material according to claim 2, wherein, The mass ratio of the modified ethylene-propylene-diene rubber, butadiene rubber and natural rubber is (1.2-1.4):(1-2):

1.

4. A high abrasion resistant, photochromic shoe sole material according to claim 2, wherein, The preparation method of the modified ethylene-propylene-diene rubber comprises the following steps: (1) 4-maleimide phenol, 1,3,5-tris(4-aminophenoxy)benzene and polyformaldehyde are mixed, stirred and dispersed uniformly in 1,4-dioxane, then heated to reflux and stirred for 3-4 days, cooled to room temperature after the end, and then n-hexane is added until no precipitate is generated, then concentrated under reduced pressure, recrystallized with tetrahydrofuran and n-hexane, then filtered and dried to obtain a crosslinking agent; (2) 4-penten-1-ol, 4-ethoxyphenol and pyridine are mixed and added into dichloromethane, then 2,5-furandicarboxylic chloride and DMAP are added, constant-temperature stirring is conducted at room temperature for 20-30 h, dilute hydrochloric acid is added after the end, stirring is conducted for 0.5-1 h, the organic phase is dried and concentrated after extraction, and column chromatography purification is conducted to obtain the compound shown in formula I (Ⅰ)； (3) the ethylene-propylene-diene rubber is melted, an initiator, the compound shown in formula I in step (2) and the crosslinking agent in step (1) are added, and the mixture is milled for 5-10 min to obtain a rubber compound, the rubber compound is placed in a hot press, taken out after hot pressing and annealed to obtain the modified ethylene-propylene-diene rubber.

5. A high abrasion resistant, photochromic shoe sole material according to claim 4, wherein, The molar ratio of the 4-maleimide phenol and 1,3,5-tris(4-aminophenoxy)benzene is (3-3.5):

1.

6. A high abrasion resistant, photochromic shoe sole material according to claim 4, wherein The molar ratio of the 4-penten-1-ol, 4-ethoxyphenol and 2,5-furandicarboxylic chloride is (0.9-1.1):(0.9-1.1):

1.

7. A high abrasion resistant, photochromic shoe sole material according to claim 4, wherein In step (3), the mass ratio of the ethylene-propylene-diene rubber, the compound shown in formula I and the crosslinking agent is 1:(0.1-0.3):(0.01-0.05).

8. A high abrasion resistant, photochromic shoe sole material according to claim 1, wherein, The additive aid is white carbon black.

9. A high abrasion resistant, photochromic shoe sole material according to claim 1, wherein, The vulcanizing agent is dicumyl peroxide.

10. A process for the preparation of the high abrasion photographic color-changing shoe sole material according to any one of claims 1 to 9, characterized by, The method comprises the following steps: the rubber composition is mixed, the additive aid, the silica sol, the silane coupling agent, the stearic acid, the vulcanizing agent and the photochromic agent are added and uniformly mixed, vulcanization treatment is conducted, and a high-wear-resistance photochromic shoe sole material is obtained.

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