Recyclable environment-friendly rubber sole material, preparation method and recycling method thereof

Abstract

The application provides a recyclable environment-friendly rubber sole material and a preparation method and a recycling method thereof. The recyclable environment-friendly rubber sole material is prepared from raw materials including carboxyl-functionalized rubber, a cross-linking agent, an antioxidant, a reinforcing agent and a plasticizer; and the recycling method is that the recyclable environment-friendly rubber sole material is crushed, hydrolyzed with a hydrolysis solution, and dried after hydrolysis. In the application, the carboxyl on the main chain of the carboxyl-functionalized rubber is used as a cross-linking point to react with an epoxy functional group on a glycidyl amine type epoxy resin to form a beta-hydroxy ester bond cross-linking bond. The beta-hydroxy ester bond cross-linking bond formed by cross-linking reaction can be hydrolyzed in an alcohol aqueous solution with a certain pH value, and the closed loop is recycled. The application does not need other vulcanization aids, the system is simple, the self-catalytic effect of the used cross-linking agent is good, and the reaction is rapid and efficient. The hydrolysis method is low-toxicity, environment-friendly, effective and simple to recycle.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of rubber materials, and further relates to a recyclable environment-friendly rubber sole material and a preparation method and a recycling method thereof. BACKGROUND

[0002] Traditional rubber sole formulations mainly have two types. The first type is a sulfur vulcanization system mainly using sulfur as a vulcanizing agent, using some nitrogen-containing and sulfur-containing substances as accelerators, using zinc oxide (ZnO) and stearic acid (SA) as activators, and adding some other processing aids. This type of system has a complex formulation design, and the added additives are often toxic to the human body or harmful to the environment, such as: Pro-CZ has an allergic reaction to human skin; Pro-D is toxic to the human body; ZnO is harmful to aquatic organisms; during the high-temperature vulcanization process, toxic smoke such as sulfur dioxide (SO2), carbon disulfide (CS2), and other VOCs gases are generated, which seriously harm the health of rubber sole production workers, etc. The second type of traditional rubber sole formulation is a peroxide crosslinking system represented by dicumyl peroxide (DCP). This type of system has a fast vulcanization speed, but the vulcanized rubber has a serious odor, which seriously affects the wearing experience of customers as a sole material, and the peroxide as a raw material itself is mostly toxic and highly active, which poses a safety hazard during transportation.

[0003] For the design of a green crosslinking system, the current main idea is to design a "epoxy-acid" reaction, introduce carboxyl / epoxy into the rubber main chain as a crosslinking point, and use multifunctional epoxy small molecules / carboxylic acid molecules as a crosslinking agent to design a crosslinking reaction. This idea has been applied to various commercialized rubbers, such as: a green crosslinking system of carboxyl nitrile rubber and epoxy soybean oil; a green crosslinking system of epoxy natural rubber (ENR) and sebacic acid. However, a common problem with these systems is that the reaction rate is low, and an imidazole catalyst needs to be added.

[0004] China is a big consumer of rubber shoes. According to incomplete statistics, nearly 100 million pairs of waste rubber shoes cannot be effectively recycled and processed every year. This is because the three-dimensional crosslinking network generated by the traditional rubber sole vulcanization process is mostly based on -S-S- bonds, -C-S- bonds, and -C-C- bonds. These chemical bonds are irreversible crosslinking bonds, making the vulcanized rubber network "difficult to melt and dissolve". Currently, the recycling of rubber sole materials is mainly through crushing the waste rubber and paving the road, or burning it as fuel. These methods cannot achieve "high-value recycling" of rubber materials.

[0005] At present, based on the "double screw desulfurization technology", through high temperature and strong shearing effect in double screw extruder to realize the method of rubber devulcanization recycling. This method can realize the devulcanization of traditional waste rubber, but the molecular weight of the reclaimed rubber is seriously reduced, and there is a "mooney rebound" phenomenon, which seriously restricts the wide use of reclaimed rubber.

[0006] Therefore, it is necessary to design a new type of green recyclable environment-friendly rubber sole formula, which should meet the following requirements: first, the formula composition is simple and practical, which can avoid the use of toxic additives, and avoid the generation of unpleasant odor and toxic gas; second, compared with other green vulcanization formulas, the crosslinking reaction is rapid, and the effective crosslinking degree of the obtained crosslinked elastomer is high; third, the rubber insole product produced by the formula can be effectively de-crosslinked by physical and chemical methods, and the recycling process is green and environmentally friendly, and the product obtained after recycling can be used for the remaking of the sole. SUMMARY

[0007] In order to solve the technical problems existing in the prior art, the present application provides a recyclable and environmentally friendly rubber sole material and a preparation method and a recycling method thereof.

[0008] The present application provides a formula based on carboxyl functionalized rubber as the rubber sole matrix material, taking the carboxyl group on the rubber main chain as the crosslinking point, and reacting with the epoxy functional group on the commercial nitrogen-containing epoxy resin, mainly glycidyl amine type epoxy resin, to form a beta-hydroxy ester bond crosslinking bond. The beta-hydroxy ester bond formed after crosslinking reaction can be hydrolyzed by acid-base catalysis in ethanol aqueous solution to obtain the corresponding carboxyl functionalized rubber of closed loop recycling, and the recycled rubber is used as the sole material matrix rubber for reprocessing.

[0009] The present application only needs to add glycidyl amine type epoxy resin as vulcanizing agent, without other vulcanizing aids, and the system is simple; the glycidyl amine type epoxy resin molecule has three or more highly active epoxy groups, and the internal tertiary amine structure can act as an internal catalyst for epoxy-acid reaction, and the reaction is rapid and efficient.

[0010] One of the purposes of the present application is to provide a recyclable and environmentally friendly rubber sole material.

[0011] The recyclable and environmentally friendly rubber sole material is prepared from raw materials including carboxyl functionalized rubber, crosslinking agent, antioxidant, reinforcing agent; preferably the raw materials further include plasticizer;

[0012] Based on 100 parts by weight of carboxyl functionalized rubber,

[0013]

[0014] In a preferred embodiment of the present application,

[0015] The carboxyl-functionalized rubber is at least one of a carboxyl-functionalized copolymer, a maleic anhydride grafted rubber, and a carboxyl grafted rubber;

[0016] The carboxyl-functionalized copolymer is at least one of acrylonitrile-butadiene-methacrylic acid copolymer, acrylonitrile-butadiene-acrylic acid copolymer, styrene-butadiene-methacrylic acid copolymer, styrene-butadiene-acrylic acid copolymer, isoprene-methacrylic acid copolymer, isoprene-acrylic acid copolymer, butadiene-methacrylic acid copolymer, butadiene-acrylic acid copolymer, butadiene-isobutylene-methacrylic acid copolymer, butadiene-isobutylene-acrylic acid copolymer, ethylene-propylene-methacrylic acid copolymer, and ethylene-propylene-acrylic acid copolymer;

[0017] The mass of the monomer containing the carboxyl functional group accounts for 0.1% to 40% of the total mass of the copolymer, and preferably 3% to 10%; that is, for each copolymer, the mass ratio of the monomer containing the carboxyl functional group to the monomer not containing the carboxyl functional group is 0.1:99.9 to 40:60, and preferably 3:97 to 10:90;

[0018] The maleic anhydride grafted rubber is at least one of maleic anhydride grafted nitrile rubber, maleic anhydride grafted styrene-butadiene rubber, maleic anhydride grafted natural rubber, maleic anhydride grafted ethylene-propylene-diene rubber, maleic anhydride grafted butyl rubber, maleic anhydride grafted butyl rubber, and a hydrolysis product thereof;

[0019] The grafting rate of the maleic anhydride is 0.1% to 40%, and preferably 3% to 35%;

[0020] The carboxyl grafted rubber is at least one of mercaptoacetic acid grafted styrene-butadiene rubber, mercaptopropionic acid grafted styrene-butadiene rubber, mercaptoacetic acid grafted cis-butadiene rubber, and mercaptopropionic acid grafted cis-butadiene rubber;

[0021] The grafting rate of the mercapto acid is 0.5% to 50%, and preferably 2% to 35%.

[0022] In a preferred embodiment of the present application,

[0023] The crosslinking agent is at least one of glycidyl amine type epoxy resins, preferably tri-glycidyl-p-aminophenol (TPAP), tri-glycidyl isocyanurate (TGIC), tetra-glycidyl-xylene diamine (TGXDA), and tetra-glycidyl-1,3-bisaminomethylcyclohexane (TGBAMCH).

[0024] In a preferred embodiment of the present application,

[0025] The anti-aging agent is at least one of anti-aging agent AW (ethoxyquinoline, 6-ethoxy-2,2,4-trimethyl-1,2-dihydroquinoline), anti-aging agent D (N-phenyl-2-naphthylamine), anti-aging agent H (N,N'-diphenyl-p-phenylenediamine), anti-aging agent 4020 (N-(1,3-dimethyl)butyl-N'-phenyl-p-phenylenediamine), anti-aging agent 4010NA (N-isopropyl-N'-phenyl-p-phenylenediamine), anti-aging agent BLE (9,9-dimethylacridine), anti-aging agent RD (2,2,4-trimethyl-1,2-dihydroquinoline polymer), anti-aging agent 2246 (2,2'-methylenebis(4-methyl-6-tert-butylphenol)); and / or,

[0026] The reinforcing agent is at least one of carbon black, calcium carbonate, white carbon black, talc, kaolin, titanium dioxide; and / or,

[0027] The plasticizer is at least one of operating oil, paraffin, coal tar, coumarone resin, polyester plasticizer.

[0028] The second object of the present application is to provide a preparation method of a recyclable environment-friendly rubber sole material, comprising:

[0029] The carboxyl-functionalized rubber is plasticized, anti-aging agents, reinforcing agents, cross-linking agents, and plasticizers are added or not added, and then mixed uniformly and vulcanized to obtain the recyclable environment-friendly rubber sole material.

[0030] In a preferred embodiment of the present application,

[0031] The vulcanization temperature is 150-220°C, preferably 150-190°C;

[0032] The vulcanization time is 5-60 minutes, preferably 10-35 minutes.

[0033] The third object of the present application is to provide a recycling method of a recyclable environment-friendly rubber sole material, comprising:

[0034] The recyclable environment-friendly rubber sole material is crushed and hydrolyzed with a hydrolysis solution, and the hydrolyzed product is washed with water and dried.

[0035] After hydrolysis using the alkaline hydrolysis solution, the product can be acidified and then dried. The acidification refers to the process of neutralizing the alkali in the hydrolysis solution by adding hydrochloric acid (HCl) with the same amount of alkali in the hydrolysis solution (the mol amount of HCl solution is the same as the alkali, and the concentration of HCl solution is 0.5 mol / L) after hydrolysis under the condition of the alkaline hydrolysis solution. The above "acidification" step is only performed when the alkali is sodium hydroxide, potassium hydroxide, lithium hydroxide, trimethylamine, triethylamine, dimethylamine, diethylamine, sodium alcoholate, or potassium alcoholate. When the hydrolysis solution is acidic, this operation is not required. Then, the product is washed with a large amount of deionized water and then dried.

[0036] The recovered product is raw rubber, and the performance is equivalent to that of the original carboxyl-functionalized rubber. The recyclable and environmentally friendly rubber sole material can be prepared by adding crosslinking agents, anti-aging agents, reinforcing agents, plasticizers, and other raw materials, uniformly mixing, and vulcanizing.

[0037] In a preferred embodiment of the present application,

[0038] The recyclable and environmentally friendly rubber sole material is crushed into particles with a particle size of 0.1-5 mm, preferably 0.1-2 mm.

[0039] The hydrolysis solution is prepared by mixing alkali or acid, water, and alcohol.

[0040] The hydrolysis solution is preferably an alkaline hydrolysis solution containing metal cations. When the hydrolysis solution is an alkaline hydrolysis solution containing Na + , K + , Li + , and other metal cations, an ionic bond can be formed with the carboxyl-containing glue, and the ionic bond has a sacrificial bond effect, which improves the tensile mechanical properties of the rubber to a certain extent.

[0041] The volume ratio of water to alcohol is 1:4-1:10, preferably 1:4-1:8.

[0042] The acid-base concentration of the hydrolysis solution is 0.1-5 mol / L, preferably 0.5-2 mol / L.

[0043] The hydrolysis temperature is 50-90°C, preferably 60-80°C.

[0044] The hydrolysis time is 6-18 h, preferably 9-18 h.

[0045] In a preferred embodiment of the present application,

[0046] The alcohol is at least one of methanol, ethanol, butanol, and isopropanol; and / or,

[0047] The base is at least one of sodium hydroxide, potassium hydroxide, lithium hydroxide, trimethylamine, triethylamine, dimethylamine, diethylamine, sodium alcoholate, potassium alcoholate; and / or,

[0048] The acid is at least one of hydrogen chloride, hydrogen bromide, hydrogen iodide, sulfuric acid.

[0049] The application can specifically adopt the following technical solutions:

[0050] The raw materials are weighed according to the above proportions;

[0051] (1) Preparation method of recyclable environment-friendly rubber sole material:

[0052] A. The carboxyl-functionalized rubber is plasticized three times on a two-roll mill of type 2*300*800 mm;

[0053] B. Set the temperature of the internal mixer: 60-100℃; preferably: 70-90℃;

[0054] C. Set the rotation speed of the internal mixer: 40-60 r / min; preferably: 45-55 r / min;

[0055] D. Add the plasticized carboxyl-functionalized rubber to the internal mixer for mixing, and the mixing time is 1-5 min; preferably: 2-3 min;

[0056] E. Add the antioxidant for mixing, and the mixing time is 30 s-3 min, preferably: 1-2 min;

[0057] F. Add the plasticizer for mixing, and the mixing time is 30 s-3 min, preferably: 1-2 min;

[0058] G. Add the reinforcing agent in two times for mixing, and the mixing time is 4-12 min, preferably: 6-10 min;

[0059] H. Take out the mixed rubber from the internal mixer, adjust the roll gap of the two-roll mill to 0.5 mm, keep the roll temperature at 50℃, and the rotation speed ratio of the front and rear cylinders is 1:1.5, plasticize the mixed rubber three times on the two-roll mill of type 2*300*800 mm, then adjust the roll gap to 0.8 mm to make the rubber wrap the roll, add the crosslinking agent, cut the knife 4 times, alternately roll 12 triangular packs and 6 rolls to uniformly disperse the small materials, and then roll out the sheets;

[0060] I. The pressure of the flat vulcanization instrument selected for the preparation of the sole sample is 15 MPa;

[0061] J. The vulcanization temperature is 150-220℃; preferably: 150-190℃;

[0062] K. The vulcanization time is 5-60 min; preferably: 10-35 min.

[0063] ​​(2) Sample hydrolysis recovery and reprocessing

[0064] A. Crush the vulcanized shoe sole sample into particles with a particle size of 0.1-5mm; preferably: 0.1-2mm;

[0065] B. Prepare the hydrolysis solution with a volume ratio of deionized water to alcohol of 1:4-1:10; preferably: 1:4-1:8;

[0066] C. Prepare the hydrolysis solution with an acid-base concentration of 0.1-5mol / L; preferably: 0.5-2mol / L;

[0067] D. Set the hydrolysis temperature to 50-90℃; preferably: 60-80℃;

[0068] E. Set the hydrolysis time to 6-18h; preferably: 9-18h;

[0069] F. Dry the hydrolyzed product, then add the crosslinking agent on a double-roller open mill using the method described in (1) H, and use the methods described in (1) I-K to prepare the reprocessed shoe sole sample;

[0070] The crosslinking agent used is the same as that used in the preparation of recyclable environmentally friendly rubber shoe sole material;

[0071] The alcohol in B is at least one of methanol, ethanol, butanol, isopropyl alcohol;

[0072] The base in C is at least one of sodium hydroxide, potassium hydroxide, lithium hydroxide, trimethylamine, triethylamine, dimethylamine, diethylamine, sodium alcoholate, potassium alcoholate;

[0073] The acid in C is at least one of hydrogen chloride, hydrogen bromide, hydrogen iodide, sulfuric acid.

[0074] The present application is based on the principle of "epoxy and acid" reaction for crosslinking reaction, and the reaction of epoxy and acid generally needs a catalyst, otherwise the crosslinking reaction is very slow, and the catalyst containing a tertiary amine group such as 1,2-dimethyl imidazole is the most important catalyst, and the catalytic principle is to form a zwitterion pair reaction by using the tertiary amine group and the epoxy type crosslinking agent. The crosslinking agent of the present application itself contains a tertiary amine group, which can internally catalyze the reaction itself, thereby forming a fast and efficient crosslinking system without catalyst. The crosslinking agent used in the present application contains a tertiary amine group, and the functionality is not less than 3. By using such crosslinking agent, the use of crosslinking catalyst (most of which are toxic) is saved, the use of toxic substances is reduced, and the vulcanization system is simplified. The crosslinking agent containing a tertiary amine group has a self-catalytic effect during the vulcanization and crosslinking reaction, and can quickly perform crosslinking reaction without catalyst. At the same time, the glycidyl amine type epoxy crosslinking agent used is a high functionality crosslinking agent, which can form more effective crosslinking and has higher crosslinking effect compared with the commonly used epoxy resin type crosslinking agent under the same amount.

[0075] At the same time, according to the self-catalytic principle, the catalytic effect is due to the formation of a zwitterion by two molecules of crosslinking agent, and the tertiary amine group of one molecule of crosslinking agent combines with the epoxy group of another molecule of crosslinking agent to form a zwitterion. The zwitterion combines with the carboxyl group in the carboxyl functionalized rubber to form a five-membered ring transition state, and then the molecule of crosslinking agent that acts as a catalyst leaves, and the epoxy and acid combine to form an ester bond crosslinking bond. The tertiary amine functional group is positively charged, and if it is to have good catalytic effect, the N+ ion of the tertiary amine needs to be stable, i.e. the group directly adjacent to the tertiary amine group needs to contain an electron-withdrawing group. Therefore, when selecting a glycidyl amine type epoxy crosslinking agent, two factors need to be considered: one factor is that the group directly adjacent to the tertiary amine group preferably has an electron-withdrawing effect, and the catalytic effect is better; the other factor is to select a low-toxicity crosslinking agent as much as possible, which is more environmentally friendly. Based on the above factors, four kinds of glycidyl amine type epoxy crosslinking agents are preferred.

[0076]

[0077] The method for using a small molecule alcohol solution of a certain pH value to decrosslink the carboxyl functionalized rubber crosslinked elastomer is also unique to the present application. In the existing recycling technology, toxic organic reagents such as tetrahydrofuran and acetone are often used as reaction media. In view of this situation, in order to reduce the use of toxic reagents and at the same time have a good swelling effect on rubber materials to facilitate the entry of acid-base small molecules into the rubber network for decrosslinking reaction, a method using non-toxic alcohol solvents as reaction media is designed.

[0078] Compared with the commonly used method of de-crosslinking, the de-crosslinking method of the application is low in toxicity, more environmentally friendly, and can achieve the same hydrolysis effect; since the rubber molecules only swell but not dissolve in the alcohol solution, compared with organic reagents such as tetrahydrofuran and acetone, the rubber after hydrolysis does not need to be flocculated out by using solvents such as ethanol, and the recovery is simpler and more convenient.

[0079] Compared with the prior art, the application has the following beneficial effects:

[0080] (1) The glycidyl amine type epoxy resin crosslinking agent used in the application has a self-catalytic effect, and can quickly perform crosslinking reaction without a catalyst; meanwhile, since the epoxy groups of the crosslinking agent used are at the molecular chain end, the functionality is large, the reactivity is higher, and more effective crosslinking is formed; the vulcanization time of the application is comparable to that of a peroxide vulcanization system, and is greatly shortened compared with the vulcanization time of a vulcanization system using glycidyl ether epoxy resin as a crosslinking agent;

[0081] (2) In addition to the glycidyl amine type epoxy resin crosslinking agent used in the application, no toxic accelerators, activators or other reaction aids need to be added, the system is simple, low in toxicity and environmentally friendly;

[0082] (3) The rubber de-crosslinking method of the application uses a small-molecule alcohol solution with a certain pH value as a hydrolysis solution, and does not use toxic organic reagents such as tetrahydrofuran and acetone, so the de-crosslinking method is low in toxicity, more environmentally friendly, and can achieve the same hydrolysis effect;

[0083] (4) In the rubber de-crosslinking method of the application, the rubber molecules only swell but not dissolve in the alcohol solution, compared with organic reagents such as tetrahydrofuran and acetone, the rubber after hydrolysis does not need to be flocculated out by using solvents such as ethanol, and the recovery is simpler and more convenient.

[0084] (5) The vulcanized rubber de-crosslinking method of the application can realize the "closed loop recycling" of the vulcanized rubber, i.e. the closed loop process from raw rubber to vulcanized rubber to raw rubber, on the one hand, the recovered raw rubber is basically the same as before processing, and the subsequent reprocessing method of the recovered rubber is more flexible, on the other hand, the "closed loop recycling" makes the recyclable and environmentally friendly rubber sole material of the application very environmentally friendly. BRIEF DESCRIPTION OF DRAWINGS

[0085] Figure 1 The infrared spectrum of the carboxyl nitrile rubber used in Example 1 and the recovered rubber after hydrolysis;

[0086] Figure 2 The nuclear magnetic spectrum of the carboxyl nitrile rubber used in Example 1 and the recovered rubber after hydrolysis. DETAILED DESCRIPTION

[0087] The present application will be described in detail below with reference to specific drawings and examples. It is necessary to point out that the following examples are only used to further illustrate the present application and cannot be understood as limiting the scope of protection of the present application. Some non-essential improvements and adjustments to the present application made by those skilled in the art based on the content of the present application still fall within the scope of protection of the present application.

[0088] The maleic anhydride grafted modified rubber and the mercapto acid grafted modified rubber used in the examples are synthesized in the laboratory; the remaining raw materials used in the examples and comparative examples are commercially available;

[0089] Main raw materials:

[0090] Acrylonitrile-butadiene-methacrylic acid copolymer rubber (carboxyl nitrile rubber, XNBR): Germany Lanxess;

[0091] Styrene-butadiene-methacrylic acid copolymer rubber (carboxyl butadiene rubber, XSBR): Shanghai Gaoqiao BASF;

[0092] Preparation of maleic anhydride grafted modified rubber:

[0093] Adjust the temperature of the Hake internal mixer to 170°C, add 100g of the rubber to be modified, and melt it completely; then add a certain amount of maleic anhydride and initiator BPO, melt graft for 10min, to obtain maleic anhydride grafted rubber. Place the graft in a Soxhlet extractor, add 70ml of acetone, and reflux extract at 85°C for 24h to make it swell fully. The purpose is to remove unreacted maleic anhydride monomer and possible maleic anhydride copolymer. Then, place it in a 70°C vacuum oven for 12h to obtain purified maleic anhydride grafted modified rubber.

[0094] Preparation of mercapto acid grafted modified rubber:

[0095] Dissolve 50g of the rubber to be modified in 1L of tetrahydrofuran, add a certain amount of 3-mercaptopropionic acid, and dissolve it fully. Then, add a certain amount of photoinitiator benzoin dimethyl ether (DMPA), and place it under a UV lamp under the protection of nitrogen atmosphere. By changing the light exposure time, different grafting rates of mercapto acid modified rubber are obtained. In Example 6, the light exposure time is 9min. After that, pour the solution into a beaker containing deionized water to flocculate, and then add the flocculated rubber to tetrahydrofuran. Repeat the above steps four times to obtain pure 3-mercaptopropionic acid grafted modified rubber.

[0096] Test method:

[0097] 1. Tensile test: CMT4104 universal material testing machine of Shenzhen Sans (SANS) Company was used. The preparation of sample strips, test method and test result processing in the standard tensile test of rubber were carried out according to the requirements of GB / T 528-2009 test standard;

[0098] 2. Infrared test: using Tensor 27 infrared spectrometer of Germany Bruker company, wave number is set to 400cm -1 to 4000cm -1 , first, the sample to be tested is dissolved in THF, after the sample is completely dissolved, the sample solution is added dropwise to the pre-pressed KBr sheet, and the test is carried out after drying in the infrared oven;

[0099] 3. Nuclear magnetic test: using AV400 type 400MHz nuclear magnetic of Bruker company for 1H-NMR characterization. Deuterated chloroform (CDCl3) is used as solvent, about 10-15mg sample is weighed and dissolved in CDCl3 for testing;

[0100] 4. GPC test: using GPC of Water 1525 type of American Waters company for molecular weight test. The sample preparation method is as follows: using THF as solvent, 100mg sample is dissolved in THF, and the concentration of sample is 5mg / mL;

[0101] 5. Vulcanization property test: using MR·C3 type rotorless vulcanization instrument of Beijing Ruida Yuchen Instrument Co., Ltd. to characterize the vulcanization property of rubber;

[0102] 6. Compression set test: the sample preparation, test method and test result processing of compression set are carried out according to the requirements of GB / T 7759.1-2015 test standard;

[0103] 7. Mooney viscosity test: GB / T 1232.1-2016 test method.

[0104] Example 1

[0105] (1) Rubber mixing: 100 parts by weight of acrylonitrile-butadiene-methyl methacrylate copolymer rubber (carboxylated nitrile rubber, XNBR) (methyl methacrylate content 7%) is weighed, the roll gap of the open mill is adjusted to 0.5mm, the roll temperature is kept at 50℃, the speed ratio of the front and rear rollers is 1:1.5, and the rubber is mixed in the open mill The rubber was mixed on a two-roll open mill for three times, the temperature of the internal mixer was adjusted to 80°C, and the speed was 60 r / min, then the rubber was added into the internal mixer and mixed for 2 min; 2 parts by weight of antioxidant 4020 was added into the internal mixer and mixed for 2 min; then 5 parts by weight of plasticizer uron resin was added into the internal mixer and mixed for 1 min; finally, 40 parts by weight of reinforcing agent / filler N330 carbon black was added into the internal mixer and mixed for 7 min, and the mixed rubber was removed from the internal mixer and cooled to room temperature. The roll gap of the open mill was adjusted to 0.8 mm, the rubber was wrapped around the roll, 3 parts by weight of crosslinking agent TGXDA was added, the knife was cut 4 times, and 12 triangular packs and 6 rolls were alternately punched to uniformly disperse the small materials, and then the sheet was discharged.

[0106] (2) vulcanization: the vulcanization temperature was set to 180°C, the vulcanization time was 9 min, the rubber was pressed into a square sheet with a thickness of 1 mm, and the rubber was pressed into a cylindrical sample with a diameter of 3 mm and a height of 1.5 mm with a sample vulcanization time of 1.5 times, to obtain a recyclable and environmentally friendly rubber sole material sample.

[0107] (3) recyclable and environmentally friendly rubber sole material disulfide recovery: 25 g of the recyclable and environmentally friendly rubber sole material sample prepared in step (2) was crushed into waste rubber particles with a particle size of 0.2 mm, an ethanol and water mixed solution was prepared, the volume ratio of ethanol to water was 4:1, sodium hydroxide was dissolved in the mixed solution to prepare a hydroxyl negative ion solution with a concentration of 1 mol / L, and a hydrolysis solution was obtained. The waste rubber powder was added to the hydrolysis solution and stirred at 70°C for 12 h. The recycled rubber was acidified, then washed with a large amount of deionized water, and dried to constant weight.

[0108] (4) Recycling of rubber: The rubber was recycled by adding a crosslinking agent and other ingredients to the rubber prepared in steps (1) and (2) and vulcanizing the rubber to obtain a sole sample, and the performance of the sole sample was tested and compared with that of the recyclable and environmentally friendly rubber sole material.

[0109] Example 2

[0110] The difference between Example 1 and Example 2 is that the vulcanization temperature is 150°C, and the vulcanization time is 33 min.

[0111] The rest of the formula, processing conditions, and recycling conditions are the same as those in Example 1.

[0112] Example 3

[0113] The difference between Example 1 and Example 3 is that:

[0114] The crosslinking agent is triepoxy-p-aminophenol (TPAP), and the amount is 5 parts by weight.

[0115] The vulcanization temperature is 170°C, and the vulcanization time is 20 min.

[0116] The remaining formulation, processing conditions, and recovery conditions are the same as in Example 1.

[0117] Example 4

[0118] The difference from Example 1 is that:

[0119] The crosslinking agent is tetraglycidyl-1,3-bisaminomethylcyclohexane (TGBAMCH) at 4 parts by weight;

[0120] The curing temperature is 160°C, and the curing time is 20 min;

[0121] The reinforcing agent is N330 carbon black at 20 parts by weight;

[0122] The remaining formulation, processing conditions, and recovery conditions are the same as in Example 1.

[0123] Example 5

[0124] The difference from Example 1 is that:

[0125] The amount of coumarone resin is 25 parts by weight;

[0126] The curing temperature is 180°C, and the curing time is 14 min;

[0127] The remaining formulation, processing conditions, and recovery conditions are the same as in Example 1.

[0128] Example 6

[0129] The difference from Example 1 is that:

[0130] The crosslinking agent is triglycidyl isocyanurate (TGIC) at 1 part by weight;

[0131] The curing temperature is set to 180°C, and the curing time is 10 min;

[0132] The remaining formulation, processing conditions, and recovery conditions are the same as in Example 1.

[0133] Example 7

[0134] The difference from Example 1 is that:

[0135] The antioxidant is a mixture of antioxidant BLE and antioxidant RD, each at 0.15 parts by weight, for a total of 0.3 parts by weight;

[0136] The reinforcing agent is a mixture of white carbon black and calcium carbonate, with 20 parts by weight of white carbon black and 40 parts by weight of calcium carbonate, for a total of 60 parts by weight;

[0137] The curing temperature is 180°C, and the curing time is 19 min;

[0138] The remaining formulation, processing conditions, and recovery conditions are the same as in Example 1.

[0139] Example 8

[0140] The difference from Example 1 is that:

[0141] The antioxidant is a mixture of antioxidant 2246 and antioxidant H, each of which is 1.5 parts by weight, for a total of 3 parts by weight;

[0142] The reinforcing agent is a mixture of calcium carbonate, talc, and kaolin, each of which is 30 parts by weight, 5 parts by weight, and 5 parts by weight, for a total of 40 parts by weight;

[0143] The curing temperature is 180°C, and the curing time is 12 min;

[0144] The remaining formulation, processing conditions, and recovery conditions are the same as in Example 1.

[0145] Example 9

[0146] The difference from Example 1 is that:

[0147] The carboxyl-functionalized rubber is styrene-butadiene-methylacrylic acid copolymer rubber (carboxylated styrene-butadiene rubber, XSBR) (methylacrylic acid content 7%);

[0148] The curing temperature is 190°C, and the curing time is 22 min;

[0149] The remaining formulation, processing conditions, and recovery conditions are the same as in Example 1.

[0150] Example 10

[0151] The difference from Example 1 is that:

[0152] The carboxyl-functionalized rubber is maleic anhydride-grafted ethylene-propylene-diene rubber (maleic anhydride grafting rate 5%);

[0153] The crosslinking agent is trisglycidyl isocyanurate (TGIC), and the amount used is 4 parts by weight;

[0154] The curing temperature is 180°C, and the curing time is 18 min;

[0155] The remaining formulation, processing conditions, and recovery conditions are the same as in Example 1.

[0156] Example 11

[0157] The difference from Example 1 is that:

[0158] The carboxyl-functionalized rubber is maleic anhydride-grafted styrene-butadiene rubber (maleic anhydride grafting rate 35%);

[0159] The cross-linking agent is selected to be triglycidyl isocyanurate (TGIC), and the amount is 8 parts by weight;

[0160] The vulcanization temperature is set to 180℃, and the vulcanization time is 13 min;

[0161] The rest of the formulation, processing conditions, and recycling conditions are the same as in Example 1.

[0162] Example 12

[0163] The difference from Example 1 is that:

[0164] The carboxyl-functionalized rubber is mercapto-propionic acid grafted butadiene rubber (grafting rate: 5%);

[0165] The cross-linking agent is tetraglycidyl xylene diamine (TGXDA), and the amount is 2 parts by weight;

[0166] The vulcanization temperature is set to 180℃, and the vulcanization time is 15 min;

[0167] The rest of the formulation, processing conditions, and recycling conditions are the same as in Example 1.

[0168] Example 13

[0169] The difference from Example 1 is that:

[0170] The carboxyl-functionalized rubber is mercapto-acetic acid grafted butadiene rubber (grafting rate: 35%);

[0171] The cross-linking agent is selected to be tetraglycidyl xylene diamine (TGXDA), and the amount is 10 parts by weight;

[0172] The vulcanization temperature is set to 180℃, and the vulcanization time is 18 min;

[0173] The rest of the formulation, processing conditions, and recycling conditions are the same as in Example 1.

[0174] Example 14

[0175] The recyclable environmentally friendly rubber sole material prepared in Example 1 is hydrolyzed for recycling;

[0176] The difference from Example 1 is that:

[0177] In the hydrolysis step, sodium hydroxide is replaced by hydriodic acid (HI), and the concentration is configured to be 2 mol / L. The hydrolysis temperature is set to 80℃, and the hydrolysis time is set to 18 h. After hydrolysis, no acidification is required;

[0178] The rest of the formulation, processing conditions, and recycling conditions are the same as in Example 1.

[0179] Example 15

[0180] The recyclable eco-friendly rubber sole material prepared in Example 1 was hydrolyzed for recycling;

[0181] The difference from Example 1 is that:

[0182] In the hydrolysis step, sodium hydroxide was replaced by triethylamine, ethanol was replaced by isopropanol, the volume ratio of isopropanol to water was 7:1, the hydrolysis temperature was set to 80°C, and the hydrolysis time was set to 9h;

[0183] The rest of the formulation, processing conditions, and recycling conditions were the same as in Example 1.

[0184] Example 16

[0185] The recyclable eco-friendly rubber sole material prepared in Example 1 was hydrolyzed for recycling;

[0186] The difference from Example 1 is that:

[0187] In the hydrolysis step, sodium hydroxide was replaced by hydrochloric acid with a concentration of 0.5mol / L, the volume ratio of ethanol to water was 7:1, the hydrolysis temperature was 80°C, and the hydrolysis time was 9h; No acidification was required after hydrolysis;

[0188] The rest of the formulation, processing conditions, and recycling conditions were the same as in Example 1.

[0189] Example 17

[0190] The recyclable eco-friendly rubber sole material prepared in Example 10 was hydrolyzed for recycling;

[0191] The difference from Example 10 is that:

[0192] In the hydrolysis step, sodium hydroxide was replaced by hydrochloric acid with a concentration of 1mol / L, the volume ratio of ethanol to water was 6:1, the hydrolysis temperature was 80°C, and the hydrolysis time was 12h; No acidification was required after hydrolysis;

[0193] The rest of the formulation, processing conditions, and recycling conditions were the same as in Example 10.

[0194] Example 18

[0195] The recyclable eco-friendly rubber sole material prepared in Example 11 was hydrolyzed for recycling;

[0196] The difference from Example 11 is that:

[0197] In the hydrolysis step, the concentration of sodium hydroxide was 0.5mol / L, the volume ratio of ethanol to water was 5:1, the hydrolysis temperature was 80°C, and the hydrolysis time was 18h;

[0198] The rest of the formulation, processing conditions, and recycling conditions were the same as in Example 11.

[0199] Example 19

[0200] The recyclable eco-friendly rubber sole material prepared in Example 1 was subjected to hydrolytic recycling;

[0201] The difference from Example 1 is that sodium hydroxide is replaced by hydrochloric acid, ethanol is replaced by isopropanol, the volume ratio of isopropanol to water is 10:1, the hydrolysis temperature is set to 90°C, the hydrolysis time is set to 18h; no acidification is required after hydrolysis;

[0202] The rest of the formulation, processing conditions, and recycling conditions are the same as in Example 1.

[0203] Comparative Example 1

[0204] The difference from Example 1 is that:

[0205] The crosslinking agent used is epoxy soybean oil (ESO) without tertiary amine structure, and the amount used is 10 parts by weight;

[0206] The curing temperature is 180°C, and the curing time is 48min;

[0207] The rest of the formulation, processing conditions, and recycling conditions are the same as in Example 1.

[0208] Comparative Example 2

[0209] The recyclable eco-friendly rubber sole material prepared in Example 1 was subjected to hydrolytic recycling;

[0210] The difference from Example 1 is that:

[0211] In the hydrolysis step, the hydrolysis solution is replaced by an aqueous solution of tetrahydrofuran (THF), the THF used is commercially available AR purity, and deionized water is used to prepare the solution, the volume ratio of THF to deionized water is 4:1;

[0212] The rest of the formulation, processing conditions, and recycling conditions are the same as in Example 1.

[0213] Comparative Example 3

[0214] The difference from Example 1 is that:

[0215] The crosslinking agent used is epoxy resin bisphenol A diglycidyl ether (BADGE) without tertiary amine structure, and the amount used is 5 parts by weight;

[0216] The curing temperature is 180°C, and the curing time is 37min;

[0217] The rest of the formulation, processing conditions, and recycling conditions are the same as in Example 1.

[0218] Comparative Example 4

[0219] The traditional sulfur vulcanization system was used.

[0220] The difference from Example 1 is that:

[0221] The crosslinking agent was replaced by sulfur 1 part by weight, stearic acid 1 part by weight, zinc oxide 3 parts by weight, and accelerator CZ 1 part by weight;

[0222] The above vulcanization system was added in an open mill, the vulcanization temperature was set to 150°C, and the vulcanization time was 28 min;

[0223] The rest of the formulation, processing conditions, and recovery conditions were the same as in Example 1.

[0224] Comparative Example 4 was designed according to an industrial sulfur vulcanization formulation. The optimal vulcanization temperature for an industrial sulfur vulcanization formulation is generally 150°C. Comparative Example 4 was mainly used to compare the hydrolysis performance of the traditional vulcanization system.

[0225] Comparative Example 5

[0226] The peroxide vulcanization system was used.

[0227] The difference from Example 1 is that:

[0228] The crosslinking agent was replaced by DCP, and the amount used was 3 parts by weight;

[0229] The vulcanizing agent was added in an open mill, the vulcanization temperature was set to 170°C, and the vulcanization time was 9 min;

[0230] The rest of the formulation, processing conditions, and recovery conditions were the same as in Example 1.

[0231] Comparative Example 5 was designed according to an industrial DCP vulcanization formulation. The optimal vulcanization temperature for an industrial DCP vulcanization formulation is generally 170°C. Comparative Example 5 was mainly used to compare the hydrolysis performance of the DCP vulcanization system.

[0232] Table 1 is a comparison of the GPC data of the original carboxyl nitrile rubber and the recovered rubber after hydrolysis in Example 1. The test results show that the molecular weight of the original carboxyl nitrile rubber and the recovered rubber changes little, and the molecular weight distribution also changes little, indicating that the recovery process does not damage the main chain of the rubber molecules.

[0233] Table 1 Comparison of GPC data of recovered rubber and original rubber in Example 1

[0234] Rubber species Mn (x 10 4 )]]> Mw (x 10 4 )]]> PDI Protocarboxylic nitrile rubber 8.6 27.0 3.16 Reclaimed rubber 7.0 23.1 3.29

[0235] From Figure 1 It can be seen that the infrared spectra of the carboxyl nitrile rubber used in Example 1 and the recovered rubber after hydrolysis are almost completely identical, indicating that this hydrolysis method does not damage the inherent functional groups of the rubber molecular chain; from Figure 2It can be seen that the NMR spectrum of the carboxyl nitrile rubber used in Example 1 and the recovered rubber after hydrolysis is also almost completely consistent, indicating that the content of the inherent functional groups of the rubber molecular chain is not changed before and after hydrolysis; the results of infrared testing and nuclear magnetic testing fully prove the effect of the hydrolysis method of the present application, and the repeated processing performance is considerable.

[0236] Table 2 Mechanical properties and curing properties of Examples 1-19 and Comparative Examples 1-5

[0237]

[0238] Table 3 Comparison of recycling performance data of Examples 1-19 and Comparative Examples 1-5

[0239]

[0240] The curing time of Examples 1-19 and Comparative Examples 1-5 in Table 2 is measured by a vulcanizer, and the curing temperature and curing time are mainly used to measure the curing rate, the lower the temperature and the shorter the time, the faster the curing rate, and at the same time, maintaining a faster curing rate and having better mechanical strength is also an important factor for measuring curing; the compression set is an important indicator for measuring the quality of the sole, and the smaller the compression set, the better the quality of the sole material.

[0241] The properties of the recycled rubber of Examples 1-19 and Comparative Examples 1-5 are listed in Table 3. The Mooney viscosity is an important standard for measuring the degree of hydrolysis, the lower the Mooney viscosity, the more crosslinking bonds are broken by hydrolysis, the better the hydrolysis effect, and the closer the recycled product to the initial product. After hydrolysis and re-crosslinking, the better the mechanical properties, the better the hydrolysis effect.

[0242] The mechanical properties of the rubber material after alkaline hydrolysis have certain improvement because the metal cations in the hydrolysis solution can form ionic bonds with the carboxyl groups, play a sacrificial bond role, and have certain enhancement on the mechanical properties of the material.

[0243] Comparative Example 1 and Comparative Example 3 use epoxy soybean oil ESO and epoxy resin bisphenol A diglycidyl ether (BADGE) crosslinking agent, respectively;

[0244] Compared with Example 1, the epoxy value of the epoxy soybean oil ESO crosslinking agent used in Comparative Example 1 is different (the epoxy value of TGXDA is 0.85, and the epoxy value of ESO is 6.5), and the relative molecular mass of ESO is much larger than that of TGXDA. In order to ensure the comparison under approximately the same crosslinking density, the amount of ESO is larger than that of TGXDA. When the amount of ESO is large, the curing rate is still smaller than that of TGXDA, indicating that the curing rate of TGXDA is fast and the curing efficiency is high, and at the same crosslinking density, the mechanical properties of TGXDA are stronger than those of ESO, and the recycling is also better than that of ESO, which further illustrates the superiority of TGXDA as a crosslinking agent.

[0245] Compared with Example 1, the epoxy value of the epoxy resin bisphenol A diglycidyl ether (BADGE) crosslinking agent used in Comparative Example 3 is similar (the epoxy value of TGXDA is 0.85, and the epoxy value of BADGE is 0.90), but there are only two epoxy groups in one BADGE molecule, and therefore the amount of BADGE is larger than that of TGXDA in order to ensure that the comparison is made at approximately the same crosslinking density. When the amount of BADGE is large, the vulcanization rate is still smaller than that of TGXDA, which indicates that the vulcanization rate of TGXDA is fast and the vulcanization efficiency is high. At the same time, the mechanical properties of TGXDA are stronger than those of BADGE, and the recycling performance of TGXDA is also better than that of BADGE, which also proves the superiority of TGXDA as a crosslinking agent.

[0246] Comparative Example 2 uses a tetrahydrofuran (THF) aqueous solution as a hydrolysis liquid. THF has good swelling effect on rubber, and the hydrolysis effect should be good. However, THF is a toxic solvent, and the alcohol solvent used in the present application is non-toxic and can achieve a hydrolysis effect comparable to that of THF, which indicates that it is a good environmentally friendly hydrolysis method that replaces toxic reagents such as THF.

[0247] Comparative Examples 4 and 5 use sulfur and DCP as crosslinking agents, respectively, and cannot be recycled by this chemical recycling method. This further indicates that the shoe sole sample designed by such a formula is superior to the traditional vulcanization system, and can reduce more waste rubber pollution, and realize high-value recycling and reuse of materials.

[0248] The data of Examples 1-19 and Comparative Examples 1-5 prove that the vulcanization system of the present application is a green crosslinking system, which is non-toxic, non-polluting, and can realize chemical closed-loop recycling under mild conditions. The multifunctional glycidyl amine crosslinking agent used in the present application has fast reaction rate and high reaction efficiency, and the hydrolysis performance of the crosslinked product is good. The present application uses an alcohol aqueous solution as a reaction medium, which is very environmentally friendly, and at the same time has good hydrolysis effect, which is comparable to the hydrolysis effect of THF organic solvent.

Claims

1. A recyclable eco-friendly rubber sole material, characterized in that: the recyclable eco-friendly rubber sole material is prepared from raw materials including carboxyl-functionalized rubber, crosslinking agent, antioxidant, reinforcing agent; in terms of 100 parts by weight of the carboxyl-functionalized rubber, the carboxyl-functionalized rubber is 100 parts by weight; the crosslinking agent is 0.1 to 10 parts by weight; the antioxidant is 0.06 to 5 parts by weight; and the reinforcing agent is 3 to 60 parts by weight; the carboxyl-functionalized rubber is at least one of a copolymer rubber containing carboxyl-functionalized monomers, a maleic anhydride grafted rubber, and a carboxyl grafted rubber; and the crosslinking agent is at least one of trisglycidyl-p-aminophenol, trisglycidyl isocyanurate, tetraglycidyl-xylene diamine, and tetraglycidyl-1,3-bisaminomethylcyclohexane. 2.The recyclable eco-friendly rubber sole material of claim 1, characterized in that: the raw materials of the recyclable eco-friendly rubber sole material further include a plasticizer; in terms of 100 parts by weight of the carboxyl-functionalized rubber, the carboxyl-functionalized rubber is 100 parts by weight; the crosslinking agent is 1 to 5 parts by weight; the antioxidant is 0.3 to 3 parts by weight; the reinforcing agent is 20 to 40 parts by weight; and the plasticizer is 5 to 25 parts by weight. 3.The recyclable eco-friendly rubber sole material of claim 1, characterized in that: the copolymer rubber containing carboxyl-functionalized monomers is at least one of acrylonitrile-butadiene-methacrylic acid copolymer rubber, acrylonitrile-butadiene-acrylic acid copolymer rubber, styrene-butadiene-methacrylic acid copolymer rubber, styrene-butadiene-acrylic acid copolymer rubber, isoprene-methacrylic acid copolymer rubber, isoprene-acrylic acid copolymer rubber, butadiene-methacrylic acid copolymer rubber, butadiene-acrylic acid copolymer rubber, butadiene-isobutylene-methacrylic acid copolymer rubber, butadiene-isobutylene-acrylic acid copolymer rubber, ethylene-propylene-methacrylic acid copolymer rubber, and ethylene-propylene-acrylic acid copolymer rubber; and the mass of the monomer containing carboxyl-functionalized groups accounts for 0.1% to 40% of the total mass of the copolymer rubber; the maleic anhydride grafted rubber is at least one of maleic anhydride grafted nitrile rubber, maleic anhydride grafted styrene-butadiene rubber, maleic anhydride grafted natural rubber, maleic anhydride grafted ethylene-propylene-diene rubber, and maleic anhydride grafted butyl rubber, and a hydrolyzate thereof; and the grafting rate of maleic anhydride is 0.1% to 40%; and the carboxyl grafted rubber is at least one of mercaptoacetic acid grafted styrene-butadiene rubber, mercaptopropionic acid grafted styrene-butadiene rubber, mercaptoacetic acid grafted cis-butadiene rubber, and mercaptopropionic acid grafted cis-butadiene rubber; and the grafting rate of mercapto acid is 0.5% to 50%. 4.The recyclable eco-friendly rubber sole material of claim 3, characterized in that: the mass of the monomer containing carboxyl-functionalized groups in the copolymer rubber containing carboxyl-functionalized groups accounts for 3% to 10% of the total mass of the copolymer rubber; the grafting rate of maleic anhydride in the maleic anhydride grafted rubber is 3% to 35%; and the grafting rate of mercapto acid in the carboxyl grafted rubber is 2% to 35%. 5.The recyclable eco-friendly rubber sole material of claim 2, characterized in that: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ The anti-aging agent is at least one of 6-ethoxy-2,2,4-trimethyl-1,2-dihydroquinoline, N-phenyl-2-naphthylamine, N,N'-diphenyl-p-phenylenediamine, N-(1,3-dimethyl)butyl-N'-phenyl-p-phenylenediamine, N-isopropyl-N'-phenyl-p-phenylenediamine, 9,9-dimethylacridine, 2,2,4-trimethyl-1,2-dihydroquinoline polymer, and 2,2'-methylenebis(4-methyl-6-tert-butylphenol); and / or, The reinforcing agent is at least one of carbon black, calcium carbonate, white carbon black, talc, kaolin, and titanium dioxide; and / or, The plasticizer is at least one of process oil, paraffin, coal tar, coumarone resin, and polyester plasticizer.

6. A method for preparing a recyclable and environmentally friendly rubber shoe sole material as described in any one of claims 1 to 5, characterized in that... The method comprises: The carboxyl-functionalized rubber is plasticized, an anti-aging agent, a reinforcing agent, a crosslinking agent, and a plasticizer are added, and the mixture is uniformly mixed and vulcanized to obtain the recyclable and environmentally friendly rubber sole material.

7. The preparation method of the recyclable and environmentally friendly rubber sole material according to claim 6, wherein: The vulcanization temperature is 150°C to 220°C; The vulcanization time is 5 minutes to 60 minutes.

8. The preparation method of the recyclable and environmentally friendly rubber sole material according to claim 6, wherein: The vulcanization temperature is 150°C to 190°C; The vulcanization time is 10 minutes to 35 minutes.

9. A method for recycling the recyclable and environmentally friendly rubber sole material according to any one of claims 1 to 5 or the recyclable and environmentally friendly rubber sole material prepared by the method according to any one of claims 6 to 8, characterized in that The method comprises: The recyclable and environmentally friendly rubber sole material is crushed, and a hydrolysis solution is used for hydrolysis, and the hydrolyzed product is washed with water and dried.

10. The recycling method of the recyclable and environmentally friendly rubber sole material according to claim 9, wherein: The recyclable and environmentally friendly rubber sole material is crushed into particles with a particle size of 0.1 to 5 mm; The hydrolysis solution is prepared by mixing an alkali or an acid, water, and an alcohol; The volume ratio of water to alcohol is 1:4 to 1:10; The acid or alkali concentration of the hydrolysis solution is 0.1 to 5 mol / L; The hydrolysis temperature is 50°C to 90°C; The hydrolysis time is 6 hours to 18 hours.

11. The recycling method of the recyclable and environmentally friendly rubber sole material according to claim 10, wherein: The particle size of the crushed recyclable and environmentally friendly rubber sole material is 0.1 to 2 mm; In the hydrolysis solution: The volume ratio of water to alcohol is 1:4 to 1:8; The acid or alkali concentration of the hydrolysis solution is 0.5 to 2 mol / L; The hydrolysis temperature is 60°C to 80°C; The hydrolysis time is 9 hours to 18 hours.

12. The recycling method of the recyclable and environmentally friendly rubber sole material according to claim 10, wherein: The alcohol is at least one of methanol, ethanol, butanol, and isopropyl alcohol; and / or, The alkali is at least one of sodium hydroxide, potassium hydroxide, lithium hydroxide, trimethylamine, triethylamine, dimethylamine, diethylamine, sodium alcoholate, and potassium alcoholate; and / or, The acid is at least one of hydrogen chloride, hydrogen bromide, hydrogen iodide, and sulfuric acid.

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