High-elasticity anti-attenuation shoe material and preparation method thereof

Abstract

The invention belongs to the technical field of polyolefin elastomers, and particularly relates to a high-elasticity anti-attenuation shoe material and a preparation method thereof. The invention aims to solve the problem that the anti-attenuation performance of the existing high-elastic shoe material is insufficient. The preparation method comprises the following steps: preparing an ethylene-octylene copolymer through solution polymerization, preparing modified nitrile rubber through low-temperature emulsion polymerization, preparing a modified reinforcing phase through surface modification, and further preparing a cross-linked elastomer through a compatible melting process; further, performing in-situ vulcanization treatment on the cross-linked elastomer to obtain a shoe material precursor, and performing antioxidant stabilization treatment on the shoe material precursor to obtain the high-elasticity anti-attenuation shoe material. The high-elasticity anti-attenuation shoe material prepared by the invention has remarkable anti-ultraviolet and heat-resistant effects, and has excellent anti-attenuation performance while having high elasticity.

Description

Technical Field

[0001] The present invention belongs to the technical field of polyolefin elastomers, and particularly relates to a highly elastic anti-decay shoe material and a preparation method thereof. Background Art

[0002] Polyolefin elastomers are a class of polymer materials with good elasticity and processability, and are widely used in various fields. Among them, ethylene-octene copolymer occupies an important position in the shoe material field due to its excellent elasticity and flexibility. Such materials can provide good wearing comfort and sports performance for footwear products. However, in practical applications, especially in increasingly harsh usage environments, traditional polyolefin elastomer shoe materials gradually reveal their performance deficiencies.

[0003] At present, the market's requirements for shoe materials not only stay at the basic elastic level, but also put forward higher standards for oil resistance, chemical corrosion resistance, and durability during long-term use, that is, anti-decay performance. For example, in some special working environments or sports scenarios, shoe materials need to be able to resist the erosion of oil stains and chemical substances to ensure their service life and functionality. At the same time, long-term wearing and repeated pressure will cause the performance of shoe materials to decay, such as a decrease in elasticity and deformation, which directly affects the wearing experience and product durability.

[0004] However, existing shoe materials based on single polyolefin elastomers often have difficulty in balancing these key performance aspects. Although ethylene-octene copolymer has good elasticity, it shows relatively weak performance in terms of oil resistance and chemical corrosion resistance. In addition, long-term oxidation, thermal aging, and mechanical stress will also cause the molecular chain to break and the cross-linked structure to change, thereby triggering the performance decay of the material. To make up for these defects, some attempts have been made in the industry, such as blending other polymers or adding additives to improve the performance of polyolefin elastomers. However, these methods often make it difficult to improve certain performances without sacrificing their original advantages, and may even introduce new problems, such as a decrease in processing performance and an increase in cost.

[0005] At present, the insufficient anti-decay performance of existing highly elastic shoe materials remains an important problem faced by the industry.

[0006] Therefore, a highly elastic anti-decay shoe material and a preparation method thereof are proposed. Summary of the Invention

[0007] The object of the present invention is to provide a high-elastic anti-fading shoe material and a preparation method thereof. The present invention prepares ethylene-octene copolymer by solution polymerization, prepares modified nitrile rubber by low-temperature emulsion polymerization, prepares modified reinforcing phase by surface modification, and further prepares a cross-linked elastomer by a compatible melting process; further, the cross-linked elastomer is subjected to in-situ vulcanization treatment to obtain a shoe material precursor, and the shoe material precursor is subjected to antioxidant stabilization treatment to obtain a high-elastic anti-fading shoe material.

[0008] To achieve the above object, the present invention provides the following technical solutions:

[0009] A method for preparing a high-elastic anti-attenuation shoe material comprises the following steps:

[0010] Unless otherwise specified, the parts in the present invention refer to parts by mass, and the average molecular weight refers to the number average molecular weight.

[0011] Ethylene and 1-octene are polymerized by solution polymerization to obtain an ethylene-octene copolymer;

[0012] The nitrile monomer, emulsifier, initiator and molecular weight regulator are mixed and subjected to low temperature emulsion polymerization to obtain modified nitrile rubber;

[0013] The titanium aluminum carbide powder is surface modified to obtain a modified reinforcement phase;

[0014] The ethylene-octene copolymer, the modified nitrile rubber and the modified reinforcing phase are blended, and an interfacial modifier, a crosslinking agent and a free radical scavenger are added to perform compatible melting to obtain a crosslinked elastomer;

[0015] The cross-linked elastomer is subjected to in-situ dynamic vulcanization treatment to obtain a shoe material precursor;

[0016] After the shoe material precursor is subjected to an anti-oxidation stabilization treatment, the shoe material is injection molded to obtain a high-elasticity and anti-attenuation shoe material.

[0017] Preferably, the process of solution polymerization is as follows: ethylene and 1-octene are introduced into a reactor at a molar ratio of 1:0.1-0.2, n-hexane, triethylaluminum and zirconocene dichloride are added under a nitrogen atmosphere, and after being fully mixed, the mixture is reacted at a rotation speed of 500-700 rpm and a reaction temperature of 50-60° C. for 60 minutes, and then the introduction of ethylene is stopped, the reaction solution is poured into excess ethanol, and the precipitated solid product is washed and dried to obtain an ethylene-octene copolymer.

[0018] The molecular weight of the ethylene-octene copolymer obtained in this step is 85,000-95,000.

[0019] Among them, the partial pressure of ethylene is controlled at 0.5 MPa; the addition amount of n-hexane is 100 parts, the addition amount of triethylaluminum is 0.2 part, and the addition amount of zirconocene dichloride is 0.02 part; while adding zirconocene dichloride, 10 parts of a toluene solution of methylaluminoxane with a solid content of 10 wt% is added as a cocatalyst.

[0020] Preferably, the process of low-temperature emulsion polymerization is as follows: 180 parts of deionized water is mixed with 3 parts of sodium dodecyl sulfate, and the mixture is kept under stirring at 500 rpm. Under nitrogen protection, 0.05 part of sodium formaldehyde sulfoxylate, 0.07 part of p-menthane hydroperoxide, 35 parts of acrylonitrile, 60 - 70 parts of 1,3-butadiene, and 0.2 - 0.8 part of tert-dodecyl mercaptan are sequentially and slowly added. After reacting for 5 - 7 hours at an operating temperature of 5 - 15 °C, the reaction mixture is subjected to vacuum distillation to remove the unreacted acrylonitrile monomer, and after washing with water and drying, modified nitrile rubber is obtained.

[0021] Preferably, the process of surface modification is as follows: Aluminum titanium carbide powder with an average particle size less than 400 mesh and a purity ≥ 98% is immersed in a 10 wt% LiF hydrochloric acid solution, where the concentration of hydrochloric acid is 15 wt%; the mixture is stirred and reacted at 35 - 50 °C for 24 hours. After washing the obtained solid product with deionized water, it is immersed in a silane coupling agent solution and treated at an ultrasonic frequency of 20 KHz for 8 hours, and then washed and dried to obtain a modified reinforcing phase.

[0022] Among them, the silane coupling agent solution is an ethanol solution of KH-570 with a concentration of 2.5 wt%.

[0023] Preferably, the process of compatibilizing and melting is as follows: After blending 60 parts of ethylene-octene copolymer, 40 parts of modified nitrile rubber, and 1 part of modified reinforcing phase that are dry, the mixture is heated to 150 - 180 °C, 0.5 part of polyethylene grafted maleic anhydride, 2 parts of ZnO, and 0.4 part of stearic acid are added. After raising the temperature to 190 - 200 °C, 0.2 part of β-(3,5-di-tert-butyl-4-hydroxyphenyl) propionic acid octadecyl ester (i.e., Irganox 1076) and 0.2 part of tris(2,4-di-tert-butylphenyl) phosphite (i.e., Irgafos 168) are added. After keeping the screw speed at 200 - 400 rpm and carrying out blending treatment for 4 - 8 hours, a crosslinked elastomer is obtained.

[0024] Among them, the CAS number of Irganox 1076 is 2082-79-3, and the CAS number of Irgafos 168 is 31570-04-4.

[0025] Among them, the average molecular weight of polyethylene grafted maleic anhydride is 4500.

[0026] Preferably, the in-situ vulcanization process is as follows: 3.2 parts of vulcanizing agent and 0.6 part of stannous chloride are added to 200 parts of crosslinked elastomer, and the screw speed is maintained at 400 rpm and the reaction temperature is 210 °C. After reacting for 2 hours, a shoe material precursor is obtained.

[0027] Among them, the vulcanizing agent is SP1045 vulcanizing resin, purchased from Shina International Trade (Shanghai) Co., Ltd.

[0028] Preferably, the antioxidant stabilization process is as follows: the shoe material precursor is cooled to 60-80 °C and kept warm and dried for 12 hours to obtain a high-elastic anti-attenuation shoe material.

[0029] A high-elastic anti-attenuation shoe material, comprising: ethylene-octene copolymer, modified nitrile rubber and modified reinforcing phase.

[0030] Compared with the prior art, the beneficial effects of the present invention are as follows:

[0031] 1. A high-elastic shoe material matrix is constructed by copolymerizing ethylene and 1-octene, and modified nitrile rubber is obtained by low-temperature emulsion polymerization. Together with the ethylene-octene copolymer, they form a composite shoe material, synergistically improving the oil resistance and chemical corrosion resistance of the shoe material product and having good elasticity.

[0032] 2. A modified reinforcing phase with high strength and rigidity is prepared by surface modification, and through the compatible melting process, it is fully combined with the ethylene-octene copolymer and modified nitrile rubber in the shoe material matrix to form a network structure, greatly enhancing the strength of the shoe material. While enhancing the interfacial bonding force of different components in the shoe material, it acts together with the interfacial modifier and crosslinking agent to optimize the internal structure of the shoe material product, improve the service life of the shoe material product, and endow it with remarkable anti-attenuation performance.

[0033] 3. Through the in-situ vulcanization treatment directly carried out after compatible melting, with the synergistic effect of the vulcanizing agent and stannous chloride, the uniform dispersion and firm combination of the modified nitrile rubber phase in the ethylene-octene copolymer matrix are realized. While comprehensively improving the elasticity and anti-attenuation of the shoe material product, it does not cause color pollution to the shoe material product.

[0034] 4. Through the antioxidant stabilization treatment of the shoe material precursor, and with the synergistic effect of the composite radical scavenger and the crosslinking agent during the compatible melting process, the oxidative degradation of the matrix materials of the shoe material product, namely modified nitrile rubber and ethylene-octene copolymer, is actively inhibited. ZnO and stearic acid crosslinking agent form chemical bonding with the functional groups on the surface of different matrix raw materials during the compatible melting process, improving the compatibility of modified nitrile rubber and ethylene-octene copolymer while ensuring the good dispersion of the modified reinforcing phase in the shoe material product, and fully balancing the strength and processing performance of the shoe material product. Description of the Drawings

[0035] Figure 1 The present invention is a process flow chart for preparing the high-elastic anti-attenuation shoe material. DETAILED DESCRIPTION

[0036] The technical solution of the present invention will be clearly and completely described below through some embodiments and experimental examples. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of them. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0037] Reference Figure 1 The present invention provides a high-elastic anti-attenuation shoe material and a preparation method thereof, and the technical solution is as follows:

[0038] Example 1

[0039] Ethylene and 1-octene were introduced into a reactor at a molar ratio of 1:0.1, and n-hexane, triethylaluminum and zirconocene dichloride were added under a nitrogen atmosphere. After being fully mixed, the mixture was reacted at a rotation speed of 500 rpm and a reaction temperature of 50° C. for 60 minutes, and then the introduction of ethylene was stopped. The reaction solution was poured into excess ethanol, and the precipitated solid product was washed and dried to obtain an ethylene-octene copolymer.

[0040] Among them, the partial pressure of ethylene is controlled at 0.5MPa; the added amount of n-hexane is 100 parts, the added amount of triethylaluminum is 0.2 parts, and the added amount of zirconocene dichloride is 0.02 parts; while adding zirconocene dichloride, 10 parts of toluene solution of methylaluminoxane with a solid content of 10wt% are added as a co-catalyst.

[0041] 180 parts of deionized water were mixed with 3 parts of sodium dodecyl sulfate, and the stirring state was maintained at 500 rpm. Under the protection of nitrogen, 0.05 parts of sodium formaldehyde sulfoxylate, 0.07 parts of menthane hydroperoxide, 35 parts of acrylonitrile, 60 parts of 1,3-butadiene and 0.2 parts of tert-dodecyl mercaptan were slowly added in sequence. After reacting at an operating temperature of 5°C for 5 hours, the reaction mixture was distilled under reduced pressure to remove the nitrile monomer involved, and the modified nitrile rubber was obtained after washing with water and drying.

[0042] Titanium carbide aluminum powder with an average particle size of less than 400 mesh and a purity of ≥98% is immersed in a 10wt% LiF hydrochloric acid solution, wherein the concentration of hydrochloric acid is 15wt%; the reaction is stirred at 35°C for 24 hours, the solid product is washed with deionized water and then immersed in a silane coupling agent solution, treated at an ultrasonic frequency of 20KHz for 8 hours, and then washed and dried to obtain a modified reinforcing phase. The silane coupling agent solution is an ethanol solution of KH-570 with a concentration of 2.5wt%.

[0043] After blending 60 parts of dry ethylene-octene copolymer, 40 parts of modified nitrile rubber, and 1 part of modified reinforcing phase, heat to 150 °C, add 0.5 part of polyethylene grafted maleic anhydride, 2 parts of ZnO, and 0.4 part of stearic acid. After raising the temperature to 190 °C, add 0.2 part of Irganox 1076 and 0.2 part of Irgafos 168. Keep the screw speed at 200 rpm and blend for 4 - 8 hours to obtain a crosslinked elastomer.

[0044] Add 3.2 parts of SP1045 curing resin and 0.6 part of stannous chloride to 200 parts of the crosslinked elastomer. Keep the screw speed at 400 rpm and the reaction temperature at 210 °C, and react for 2 hours to obtain a shoe material precursor.

[0045] Cool the shoe material precursor to 60 °C and keep it warm and dry for 12 hours to obtain a highly elastic anti-attenuation shoe material.

[0046] Examples 2 - 20 are different from Example 1 in terms of operating parameters, but the process sequence and design are the same. The relevant parameter changes are summarized in Tables 1 and 2.

[0047] Table 1 Changes in operating parameters of Examples 1 - 20 (I)

[0048]

[0049]

[0050] Table 2 Changes in operating parameters of Examples 1 - 20 (II)

[0051]

[0052]

[0053] Comparative Example 1

[0054] Different from Example 1, no modified nitrile rubber is added, and other process parameters are the same.

[0055] Comparative Example 2

[0056] Different from Example 1, a polyethylene elastomer with the same molecular weight is used to replace the ethylene-octene copolymer, and other process parameters are the same.

[0057] Comparative Example 3

[0058] Different from Example 1, the reaction temperature of low-temperature emulsion polymerization is changed to 25 °C, and other process parameters are the same.

[0059] Comparative Example 4

[0060] Different from Example 6, unmodified titanium aluminum carbide was used instead of the modified reinforcing phase, and other process parameters were the same.

[0061] Comparative Example 5

[0062] Different from Example 6, the average molecular weight of the added maleic anhydride grafted polyethylene was changed to 2500, and other process parameters were the same.

[0063] Comparative Example 6

[0064] Different from Example 11, sulfur was used instead of SP1045 curing resin as the curing agent, and other process parameters were the same.

[0065] Comparative Example 7

[0066] Different from Example 11, stannous chloride was not added during the in-situ vulcanization treatment, and other process parameters were the same.

[0067] Comparative Example 8

[0068] Different from Example 11, the modified nitrile rubber was vulcanized immediately after low-temperature emulsion polymerization, and the in-situ vulcanization treatment after compatible melting was not carried out, and other process parameters were the same.

[0069] Comparative Example 9

[0070] Different from Example 16, only ZnO was added as the crosslinking agent, and stearic acid was not added, and other process parameters were the same.

[0071] Comparative Example 10

[0072] Different from Example 16, Irganox 1076 was not added, and other process parameters were the same.

[0073] Comparative Example 11

[0074] Different from Example 16, Irgafos 168 was not added, and other process parameters were the same.

[0075] Experimental Example 1

[0076] The elasticity, oil resistance and chemical corrosion resistance of the highly elastic anti-decay shoe materials prepared in Test Examples 1-5 and Comparative Examples 1-3 were tested, and the obtained data were summarized in Table 3.

[0077] The test method for elasticity is as follows: Prepare the shoe material sample into a cylindrical specimen with a thickness of 2 cm and a bottom radius of 5 cm. Apply pressure at 25°C until the deformation reaches 50%, maintain for 24 hours, then release the pressure and let it recover for 30 minutes. Measure the final thickness and calculate the compression deformation rate. Compression deformation rate (%) = (initial thickness - final thickness) / (initial thickness - thickness after compression). The smaller the compression deformation rate, the better the elasticity of the sample.

[0078] The test method for oil resistance is as follows: Prepare the shoe material sample into a cylindrical specimen with a thickness of 2 cm and a bottom radius of 5 cm. Immerse it in silicone oil at 25°C for 72 hours, detect the mass change rate (%) before and after immersion, and observe whether there is swelling. The greater the mass change, the worse the oil resistance.

[0079] The test method for chemical corrosion resistance is as follows: Refer to the test method for oil resistance, use hydrochloric acid with a concentration of 10 wt% instead of silicone oil, detect the mass change rate (%) before and after immersion, and observe whether there is cracking. The greater the mass change, the worse the chemical corrosion resistance.

[0080] Table 3 Elasticity, oil resistance and chemical corrosion resistance of the highly elastic anti - attenuation shoe materials prepared in Examples 1 - 5 and Comparative Examples 1 - 3

[0081]

[0082] As shown in the data in Table 3, the shoe material products prepared in Examples 1 - 5 have good elasticity, oil resistance and chemical corrosion resistance. The change of process parameters has no significant impact on the performance of the shoe material products. In Comparative Example 1, no modified nitrile rubber was added, resulting in a decrease in both oil resistance and chemical corrosion resistance. In Comparative Example 2, since polyethylene elastomer was used to replace ethylene - octene copolymer, the compression deformation rate increased significantly, indicating a significant decrease in its elasticity. In Comparative Example 3, due to the too high temperature of low - temperature emulsion polymerization, the performance of the prepared modified nitrile rubber decreased, resulting in a decrease in the elasticity of the shoe material product. In summary, ethylene - octene copolymer is the key material for constructing the matrix of highly elastic shoe materials. At the same time, the addition of modified nitrile rubber can synergistically act with ethylene - octene copolymer to form a composite shoe material system, thereby improving oil resistance and chemical corrosion resistance. Low - temperature polymerization reaction strengthens the binding effect between modified nitrile rubber and ethylene - octene copolymer, effectively improving the elasticity, oil resistance and chemical corrosion resistance of the shoe material product.

[0083] Experimental Example 2

[0084] Test the mechanical strength and anti - attenuation of elasticity of the highly elastic anti - attenuation shoe materials prepared in Examples 6 - 10 and Comparative Examples 4 - 5. The obtained data are summarized in Table 4.

[0085] The test method for mechanical strength is as follows: Use a universal material testing machine to clamp a shoe material specimen of 10mm×20mm×100mm and test its tensile strength (MPa). The higher the tensile strength, the higher the mechanical strength.

[0086] The test method for the anti-attenuation property of elasticity is as follows: Refer to the method in Experimental Example 1 to test the compression deformation rate of the sample in the initial state. Subsequently, take the same sample and irradiate it under a UV intensity of 313nm and 0.55W / m 2 / nm for 24 hours, then conduct an elasticity test. Compare the compression deformation rates before and after UV irradiation. The larger the difference, the worse the anti-attenuation property of the elasticity of the shoe material.

[0087] Table 4 Mechanical strength and anti-attenuation property of elasticity of the highly elastic anti-attenuation shoe materials prepared in Examples 6-10 and Comparative Examples 4-5

[0088]

[0089] As shown in the data in Table 4, the tensile strengths of Examples 6-10 are significantly higher than those of Comparative Examples 4-5, indicating that the shoe materials in the examples have obvious advantages in mechanical strength. Moreover, the initial compression deformation rates of Examples 6-10 are similar to those of Comparative Examples 4-5. At the same time, in terms of the increase amplitude of the compression deformation rate after attenuation, Examples 6-10 are significantly smaller than Comparative Examples 4-5, indicating that the shoe materials in the examples have less elastic attenuation after UV irradiation and better anti-attenuation performance.

[0090] In Comparative Example 4, unmodified titanium aluminum carbide was used instead of the modified reinforcing phase, resulting in a significant decrease in tensile strength and some loss of anti-attenuation performance; the average molecular weight of the maleic anhydride grafted polyethylene used in Comparative Example 5 was 2500, which was lower than 4500 in the examples, leading to a slight decrease in tensile strength and a significant decrease in the anti-attenuation performance of elasticity. In summary, the modified reinforcing phase prepared by surface modification is fully combined with the shoe material matrix, improving the mechanical strength of the shoe material product. Moreover, during the compatible melting process, the interfacial modifier and crosslinking agent synergistically form a network structure, optimizing the internal structure; the combined action of these process methods and material combinations enables the shoe material product to have high strength and high anti-attenuation performance of elasticity.

[0091] Experimental Example 3

[0092] Refer to Experimental Example 2 to test the anti-attenuation property of elasticity and color pollution of the highly elastic anti-attenuation shoe materials prepared in Examples 11-15 and Comparative Examples 6-8. The obtained data are summarized in Table 5.

[0093] The test method for color pollution is as follows: Contact the shoe material sample with white cotton cloth under a pressure of 1MPa for 24 hours and observe the color transfer and pollution on the surface of the cotton cloth.

[0094] Table 5 Elastic anti - attenuation properties and color pollution conditions of the highly elastic anti - attenuation shoe materials prepared in Examples 11 - 15 and Comparative Examples 6 - 8

[0095]

[0096]

[0097] As shown in the data of Table 5, the highly elastic anti - attenuation shoe materials of Examples 11 - 15 performed excellently in terms of elastic anti - attenuation properties and color pollution control, significantly superior to Comparative Examples 6 - 8. The specific data show that the initial compression deformation rate of the shoe materials in Examples 11 - 15 was 31.5% - 33.5%, and the compression deformation rate after attenuation only increased by 4.9% - 5.6%, with no color pollution; while the initial compression deformation rate of Comparative Examples 6 - 8 was 32.4% - 37.5%, and the compression deformation rate after attenuation increased by 8.6% - 11.7%, accompanied by slight to obvious color pollution. These results show that the shoe materials of the examples effectively controlled attenuation and color pollution while maintaining elasticity, with better comprehensive performance.

[0098] In Comparative Example 6, sulfur was used instead of SP1045 vulcanizing resin for vulcanization treatment, resulting in obvious color pollution and a decline in elastic anti - attenuation performance at the same time. This indicates that sulfur vulcanization cannot effectively control side reactions, affecting the appearance and performance of the shoe material. In Comparative Example 7, stannous chloride was not added during in - situ vulcanization treatment, resulting in a significant decline in elastic anti - attenuation performance, and although the color pollution was slight, it still existed. The absence of stannous chloride weakened the stability of the vulcanization system, affecting the elastic retention ability. In Comparative Example 8, the modified nitrile rubber was directly vulcanized after low - temperature emulsion polymerization without in - situ vulcanization treatment after compatible melting, resulting in a significant decline in elastic anti - attenuation performance and slight color pollution. This shows that the compatible melting step is crucial for optimizing the material structure.

[0099] In summary, through compatible melting and in - situ vulcanization treatment, the modified nitrile rubber was uniformly dispersed and firmly bonded in the ethylene - octene copolymer matrix, forming a stable internal structure, improving the elasticity and anti - attenuation performance of the shoe material; at the same time, SP1045 vulcanizing resin provided efficient vulcanization effect, avoiding color pollution, and stannous chloride as an additive enhanced the stability of the vulcanization system, further optimizing the elastic anti - attenuation performance. The synergistic effect of these processes and substances achieved the full combination of the modified nitrile rubber and the matrix, not only significantly improving the elasticity and anti - attenuation performance of the shoe material, but also effectively avoiding color pollution, showing excellent comprehensive performance.

[0100] Experimental Example 4

[0101] Test the elastic anti - attenuation properties of the highly elastic anti - attenuation shoe materials prepared in Examples 16 - 20 and Comparative Examples 9 - 11 after ultraviolet treatment and heat treatment. The obtained data are summarized in Table 6.

[0102] The test method for the anti-attenuation property of the elasticity after ultraviolet treatment refers to Experimental Example 2.

[0103] The test method for the anti-attenuation property of the elasticity after heat treatment is the same as that after ultraviolet treatment, except that the 24-hour ultraviolet treatment is changed to heat treatment at 70 °C for 48 hours.

[0104] Table 6 Anti-attenuation properties of the high-elastic anti-attenuation shoe materials prepared in Examples 16-20 and Comparative Examples 9-11 after ultraviolet treatment and heat treatment

[0105]

[0106] As shown in the data in Table 6, the increase in the compression deformation rate of the high-elastic anti-attenuation shoe materials prepared in Examples 16-20 after ultraviolet treatment and heat treatment is significantly lower than that in Comparative Examples 9-11, indicating the excellent performance of the examples in suppressing oxidative degradation and maintaining elasticity. This performance improvement is due to the synergistic effect of antioxidant stabilization treatment, free radical scavengers Irganox 1076 and Irgafos 168, and cross-linking agents ZnO and stearic acid. In Comparative Example 9, only ZnO was used and stearic acid was not added, resulting in a decrease in cross-linking strength and difficulty in fully incorporating the free radical scavenger into the shoe material matrix network, leading to a significant decrease in anti-attenuation property. Comparative Example 10 lacked Irganox 1076, resulting in a significant decrease in the performance of anti-ultraviolet aging, while Comparative Example 11 lacked Irgafos 168, resulting in a significant exacerbation of thermal aging.

[0107] In summary, the antioxidant stabilization treatment stabilizes the internal structure and reduces the basis of oxidative degradation by cooling the shoe material precursor to 60-80 °C and keeping it warm and dry for 12 hours; the free radical scavengers Irganox 1076 and Irgafos 168 target ultraviolet- and heat-induced free radical reactions respectively to protect the polymer chain integrity of modified nitrile rubber and ethylene-octene copolymer; the cross-linking agents ZnO and stearic acid promote chemical bonding in the compatible melt to form a dense network structure, improving compatibility and dispersibility. This multi-level synergistic mechanism effectively inhibits the oxidative degradation of the matrix material, optimizes the strength and processing performance of the shoe material, and achieves high anti-attenuation properties of the elasticity after ultraviolet and heat treatment.

[0108] Although the embodiments of the present invention have been shown and described, it will be understood by those of ordinary skill in the art that various changes, modifications, substitutions and variations can be made therein without departing from the principles and spirit of the present invention, and the scope of the present invention is defined by the appended claims and their equivalents.

Claims

1. A method for preparing a high-elastic anti-attenuation shoe material, characterized in that: The preparation method is as follows: Ethylene and 1-octene are polymerized by solution polymerization to obtain an ethylene-octene copolymer; The nitrile monomer, emulsifier, initiator and molecular weight regulator are mixed and subjected to low temperature emulsion polymerization to obtain modified nitrile rubber; The titanium aluminum carbide powder is surface modified to obtain a modified reinforcement phase; The ethylene-octene copolymer, the modified nitrile rubber and the modified reinforcing phase are blended, and an interfacial modifier, a crosslinking agent and a free radical scavenger are added to perform compatible melting to obtain a crosslinked elastomer; The cross-linked elastomer is subjected to in-situ vulcanization treatment to obtain a shoe material precursor; The high-elastic anti-attenuation shoe material is obtained by subjecting the shoe material precursor to an anti-oxidation stabilization treatment.

2. The method for preparing a high-elastic anti-fading shoe material according to claim 1, characterized in that: The process of the solution polymerization is as follows: the ethylene and the 1-octene are introduced into a reactor at a molar ratio of 1:0.1-0.2, n-hexane, triethylaluminum and zirconocene dichloride are added under a nitrogen atmosphere, and after being fully mixed, the mixture is reacted at a rotation speed of 500-700 rpm and a reaction temperature of 50-60° C. for 60 minutes, and then the introduction of the ethylene is stopped, the reaction solution is poured into ethanol, and the precipitated solid product is washed and dried to obtain the ethylene-octene copolymer.

3. The method for preparing a high-elastic anti-attenuation shoe material according to claim 1, characterized in that: The nitrile monomer includes acrylonitrile and 1,3-butadiene; the emulsifier is sodium dodecyl sulfate; the initiator includes para-menthane hydroperoxide and sodium formaldehyde sulfoxylate; and the molecular weight regulator is tert-dodecyl mercaptan.

4. The method for preparing a high-elastic anti-attenuation shoe material according to claim 1, characterized in that: The process of the low-temperature emulsion polymerization is: deionized water and the emulsifier are mixed, and the stirring state is maintained. The initiator, the nitrile monomer and the molecular weight regulator are added in sequence under nitrogen protection. After reacting for 5-7 hours at an operating temperature of 5-15° C., the residual nitrile monomer is removed from the reaction mixture by reduced pressure distillation, and the modified nitrile rubber is obtained after washing with water and drying.

5. The method for preparing a high-elastic anti-attenuation shoe material according to claim 1, characterized in that: The surface modification process is as follows: immersing the titanium aluminum carbide powder in a hydrochloric acid solution of LiF, stirring and reacting at 35-50° C. for 24 hours, washing the obtained solid product with deionized water and then immersing it in a silane coupling agent solution, and obtaining the modified reinforcement phase after ultrasonic-assisted infiltration treatment.

6. The method for preparing a high-elastic anti-fading shoe material according to claim 1, characterized in that: The interface modifier is polyethylene grafted maleic anhydride; the crosslinking agent includes ZnO and stearic acid; the free radical scavenger includes (β-(3,5-di-tert-butyl-4-hydroxyphenyl) propionate) and tris(2,4-di-tert-butylphenyl) phosphite.

7. The method for preparing a high-elastic anti-attenuation shoe material according to claim 1, characterized in that: The compatible melting process is: after the dried ethylene-octene copolymer, the modified nitrile rubber and the modified reinforcing phase are blended, the mixture is heated to 150-180° C., the interfacial modifier and the crosslinking agent are added, the free radical scavenger is added after the temperature is raised to 190-200° C., the screw speed is maintained at 200-400 rpm, and the crosslinking elastomer is obtained after the blending treatment for 4-8 hours.

8. The method for preparing a high-elastic anti-fading shoe material according to claim 1, characterized in that: The process of the in-situ vulcanization treatment is as follows: adding a vulcanizing agent and stannous chloride to the cross-linked elastomer, maintaining a screw speed of 400 rpm and a reaction temperature of 210° C., and reacting for 2 hours to obtain the shoe material precursor.

9. The method for preparing a high-elastic anti-fading shoe material according to claim 1, characterized in that: The process of the anti-oxidation stabilization treatment is as follows: cooling the shoe material precursor to 60-80° C., and drying the shoe material for 12 hours to obtain the high-elastic anti-attenuation shoe material.

10. A high-elastic anti-attenuation shoe material, characterized by: The high-elastic anti-attenuation shoe material is prepared by the preparation method according to any one of claims 1 to 9; The high-elastic anti-attenuation shoe material comprises: ethylene-octene copolymer, modified nitrile rubber and modified reinforcing phase.

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