An epdm rubber material having self-adhesion after vulcanization and a method for producing the same

Abstract

The application relates to the technical field of rubber material production, in particular to an EPDM rubber material with self-adhesion after vulcanization and a preparation method thereof. The EPDM rubber material comprises the following components in mass fractions: 70-90 parts of EPDM raw rubber, 3-7 parts of modified resin, 2-9 parts of tackifying resin, 10-25 parts of porous nanometer carbon balls, 6-15 parts of polyester plasticizer, 3-6 parts of nanometer zinc oxide, 1-4 parts of stearic acid, 0.5-2 parts of anti-aging agent, 0.5-2 parts of accelerator and 0.5-3 parts of vulcanizing agent. The EPDM material has the characteristics of strong self-adhesion, no oil separation, high mechanical property and good heat-resistant stability. The modified resin is introduced into the EPDM raw rubber to crosslink with the EPDM raw rubber, the tackifying resin and the polyester plasticizer are used, the mechanical property, heat resistance and self-adhesion of the material are effectively improved, and the porous nanometer carbon balls are introduced to effectively improve the oil separation of the EPDM rubber material.

Description

Technical Field

[0001] This invention relates to the field of rubber material production technology, specifically to an EPDM rubber material with self-adhesive properties after vulcanization and its preparation method. Background Technology

[0002] Most rubber products require different parts to be bonded together during vulcanization, thus most rubber formulations need to consider self-adhesion. Self-adhesion refers to the ability of unvulcanized rubber compounds to adhere to each other, and it is caused by the diffusion of molecules on the rubber surface through thermal motion. For components such as automotive window seals, radiator hoses, building waterproofing membranes, and sealing strips, ethylene propylene diene monomer (EPDM) rubber is commonly used. These rubber products require vulcanized EPDM rubber to have good self-adhesion, enabling it to better bond with other components or itself, achieving sealing, leak prevention, and heat insulation without the need for large amounts of additional adhesives.

[0003] For EPDM rubber, its low number of active groups and weak intermolecular forces make it difficult to form good self-adhesion after vulcanization. On the other hand, to improve the processing performance and reduce production costs, plasticizers, softeners, and filler oils are often added during the preparation of rubber products. However, during vulcanization, these low-molecular-weight components may not be fully integrated into the cross-linking network; some migrate to the product surface to form a thin layer, resulting in a significant reduction in the product's self-adhesion. Therefore, there is an urgent need to propose solutions to improve the self-adhesion of EPDM rubber materials after vulcanization to meet the requirements of downstream applications. Summary of the Invention

[0004] The purpose of this invention is to overcome the shortcomings of the prior art by providing an EPDM rubber material with self-adhesive properties after vulcanization and its preparation method.

[0005] The objective of this invention is achieved through the following technical solution: an EPDM rubber material with self-adhesive properties after vulcanization, wherein the EPDM rubber material comprises the following components in parts by weight: 70-90 parts of EPDM raw rubber, 3-7 parts of modified resin, 2-9 parts of tackifying resin, 10-25 parts of porous nano-carbon spheres, 6-15 parts of polyester plasticizer, 3-6 parts of nano-zinc oxide, 1-4 parts of stearic acid, 0.5-2 parts of antioxidant, 0.5-2 parts of accelerator, and 0.5-3 parts of vulcanizing agent.

[0006] Furthermore, the vinyl content of the EPDM raw rubber is 50-60%.

[0007] Furthermore, the EPDM rubber material also includes 10-20 parts of epoxy natural rubber and 3-8 parts of maleic anhydride-grafted ethylene vinyl acetate copolymer.

[0008] In this invention, by adding epoxy natural rubber and maleic anhydride-grafted ethylene vinyl acetate copolymer to the EPDM matrix, the epoxy groups can interact with the EPDM and maleic anhydride-grafted ethylene vinyl acetate copolymer, thereby improving the compatibility of the entire reaction system and forming an effective reinforcing network. This increases the crosslinking density of the EPDM material, thereby effectively improving the tensile strength, tear strength and elasticity of the EPDM rubber material, and also enhancing the material's aging resistance.

[0009] Furthermore, the preparation method of the modified resin includes the following steps: adding aralkyl phenolic resin and anhydrous potassium carbonate to N,N-dimethylformamide, purging with nitrogen gas, adding allyl bromide dropwise and stirring thoroughly, raising the temperature to 80-85℃ and reacting overnight, then filtering and taking the filtrate for rotary evaporation, adding the concentrated rotary evaporation solution to deionized water and stirring to disperse, then extracting with dichloromethane multiple times, rotary evaporating the extract, and placing it in a vacuum oven to remove the solvent, thereby obtaining the modified resin.

[0010] In this invention, the phenolic resin is modified by the above method to contain unsaturated propylene groups, which can react with the double bonds in EPDM, thereby promoting the formation of a cross-linking network between rubber molecular chains. This results in the vulcanized EPDM rubber material having better heat resistance and mechanical properties. Furthermore, this cross-linking effect forms active groups on the material surface and enhances interfacial compatibility, thereby significantly improving the self-adhesiveness of the EPDM material.

[0011] Furthermore, the preparation method of porous carbon nanospheres includes the following steps:

[0012] A1. Add resorcinol to a mixture of ammonia and ethanol at 55-60℃ and stir until homogeneous. Then add formaldehyde solution, keep warm and stir for 12-24 hours. After centrifugation, dissolve the product in deionized water and disperse it evenly to obtain a dispersion.

[0013] A2. Add 10 mL of the dispersion to the mixture of ammonia and ethanol and stir until homogeneous. Then add hexadecyltrimethylammonium bromide and stir for 1-1.5 h. Then add ethyl silicate and continue stirring for 2.5-3 h. After centrifugation, washing and drying, the crude product is obtained.

[0014] A3. The crude product is kept at 380-400℃ for 1.5-2 hours, and then kept at 800-900℃ for 1-1.5 hours. The calcined product is added to hydrofluoric acid and stirred for 20-24 hours. After the process, the porous carbon nanospheres are obtained by centrifugation, washing and drying.

[0015] Furthermore, in step A1, the mass ratio of ammonia, anhydrous ethanol, and water in the ammonia-water and ethanol-water mixture is 0.3:8:48. In step A2, the mass ratio of ammonia, anhydrous ethanol, and water in the ammonia-water and ethanol-water mixture is 0.3:40:50.

[0016] In this invention, hollow carbon nanospheres with a porous structure and a large specific surface area, with a particle size of 200-400 nm, are prepared using the above-described method. Due to their abundant pores, they can adsorb small molecules in the matrix, thereby significantly reducing oil separation in the rubber. Furthermore, the addition of porous carbon nanospheres can act as a reinforcing agent, improving the mechanical strength and wear resistance of the EPDM rubber material. Simultaneously, the excellent thermal stability of the porous carbon nanospheres effectively enhances the heat resistance of the EPDM.

[0017] Furthermore, the tackifying resin is at least one of terpene phenolic resin, C9 petroleum resin, octylphenolic tackifying resin, and polymerized rosin. Preferably, the tackifying resin is a compound of terpene phenolic resin 801L, styrene-modified C9 petroleum resin, and octylphenolic tackifying resin in a mass ratio of 3:4-4.5:2.

[0018] Furthermore, the preparation method of the polyester plasticizer includes the following steps: succinic acid, hexanediol, and 3-chloro-1,2-hexanediol are added to a reaction vessel containing toluene, nitrogen gas is introduced to purge the air, the temperature of the reaction vessel is raised to 105-110℃ and stirred evenly, then 0.02-0.1 wt% of tetrabutyl titanate is added, the temperature is further raised to 145-155℃ for esterification reaction, until no water is produced in the reaction system, the temperature is raised again to 188-192℃ for polycondensation reaction, and the reaction product is purified to obtain the polyester plasticizer.

[0019] Furthermore, the molar ratio of succinic acid, hexanediol and 3-chloro-1,2-hexanediol is 4.76:3.5-4.5:1, and the molecular weight of the polyester plasticizer is 3000-4000.

[0020] In this invention, the polyester plasticizer prepared by the above method can penetrate into the EPDM molecular chain and play a plasticizing role, which is beneficial to increase the flexibility and self-adhesion of EPDM material, and can effectively improve the low temperature elasticity and oil resistance of EPDM material.

[0021] Furthermore, the antioxidant is at least one selected from octyl diphenylamine, dilaurate thiodipropionate, N-isopropyl-N'-phenyl-p-phenylenediamine, and N-(1,3-dimethylbutyl)-N'-phenyl-p-phenylenediamine.

[0022] Furthermore, the vulcanizing agent is sulfur or dicumyl peroxide.

[0023] Furthermore, the accelerator is at least one of accelerator TMTD, accelerator TETD, accelerator CZ, and accelerator M.

[0024] This invention also provides a method for preparing the above-mentioned self-adhesive EPDM rubber material after vulcanization, comprising the following steps: weighing each raw material according to the weight parts, placing EPDM raw rubber, modified resin, tackifying resin and polyester plasticizer in a two-roll mill for plasticizing, then adding porous nano carbon balls, nano zinc oxide, stearic acid and antioxidant and mixing for 3-6 minutes, finally adding vulcanizing agent and accelerator and mixing evenly, and vulcanizing at 140-160℃ for 8-12 minutes to obtain the EPDM rubber material.

[0025] The beneficial effects of this invention are as follows: This invention provides an EPDM rubber material with self-adhesive properties after vulcanization and its preparation method. The EPDM material has the characteristics of strong self-adhesion, no oil separation, high mechanical properties, and good heat resistance. Specifically, by introducing a modified resin into the EPDM raw rubber to crosslink it, and by using a tackifying resin and a polyester plasticizer, the mechanical properties, heat resistance, and self-adhesiveness of the material can be effectively improved. On the other hand, by introducing porous carbon nanospheres, their abundant pores and large specific surface area not only play a reinforcing role but also adsorb small molecule substances precipitated from the matrix, thereby effectively improving the oil separation properties of the EPDM rubber material. Detailed Implementation

[0026] To facilitate understanding by those skilled in the art, the present invention will be further described below with reference to embodiments. The content mentioned in the embodiments is not intended to limit the present invention.

[0027] Example 1

[0028] This embodiment provides an EPDM rubber material with self-adhesive properties after vulcanization. The EPDM rubber material comprises the following components in parts by weight: 70 parts EPDM raw rubber, 4 parts modified resin, 3 parts tackifying resin, 10 parts porous carbon nanospheres, 7 parts polyester plasticizer, 4 parts nano zinc oxide, 2 parts stearic acid, 1 part antioxidant, 1 part accelerator, and 0.5 parts vulcanizing agent.

[0029] Furthermore, the vinyl content of the EPDM raw rubber is 51%.

[0030] Furthermore, the preparation method of the modified resin includes the following steps: Aryl phenolic resin (MEH-7800S) and anhydrous potassium carbonate at a mass ratio of 1.5:1 are added to 150 mL of N,N-dimethylformamide. After purging with nitrogen, allyl bromide (the mass ratio of aryl phenolic resin to allyl bromide is 1:0.6) is added dropwise and stirred thoroughly. The temperature is raised to 80°C and the reaction is carried out overnight. Then, the filtrate is filtered and the filtrate is rotary evaporated. The concentrated rotary evaporated liquid is added to deionized water and stirred to disperse. Then, it is extracted multiple times with dichloromethane. The extract is rotary evaporated and placed in a vacuum oven to remove the solvent, thus obtaining the modified resin.

[0031] Furthermore, the preparation method of porous carbon nanospheres includes the following steps:

[0032] A1. Add 1g of resorcinol to a mixture of ammonia and ethanol at 55℃ and stir until homogeneous. Then add 1.4mL of formaldehyde solution, keep warm and stir for 16h. After centrifugation, dissolve the product in deionized water and disperse it evenly to obtain a dispersion with a concentration of 5g / L.

[0033] A2. Add 10 mL of dispersion to a mixture of ammonia and ethanol and stir until homogeneous. Then add 0.3 g of hexadecyltrimethylammonium bromide and stir for 1 h. Then add 1 mL of ethyl silicate and continue stirring for 2.5 h. After centrifugation, washing and drying, the crude product is obtained.

[0034] A3. The crude product was kept at 380℃ for 2 hours, and then kept at 800℃ for 1 hour. The calcined product was added to 20% hydrofluoric acid and stirred for 20 hours. After the calcination, the porous carbon nanospheres were obtained by centrifugation, washing and drying.

[0035] Furthermore, in step A1, the mass ratio of ammonia, anhydrous ethanol, and water in the ammonia-water and ethanol-water mixture is 0.3:8:48. In step A2, the mass ratio of ammonia, anhydrous ethanol, and water in the ammonia-water and ethanol-water mixture is 0.3:40:50.

[0036] Furthermore, the tackifying resin is a compound of terpene phenolic resin 801L, styrene-modified C9 petroleum resin and octylphenolic tackifying resin in a mass ratio of 3:4:2.

[0037] Furthermore, the preparation method of the polyester plasticizer includes the following steps: succinic acid, hexanediol, and 3-chloro-1,2-hexanediol are added to a reaction vessel containing toluene, nitrogen gas is introduced to purge the air, the temperature of the reaction vessel is raised to 105°C and stirred evenly, then 0.03 wt% tetrabutyl titanate is added, the temperature is raised to 145°C to carry out an esterification reaction until no water is produced in the reaction system, the temperature is raised again to 190°C to carry out a polycondensation reaction, and the reaction product is purified to obtain the polyester plasticizer.

[0038] Furthermore, the molar ratio of succinic acid, hexanediol and 3-chloro-1,2-hexanediol is 4.76:3.5:1.

[0039] Furthermore, the antioxidant is N-isopropyl-N'-phenyl-p-phenylenediamine.

[0040] Furthermore, the vulcanizing agent is sulfur.

[0041] Furthermore, the accelerator is a compound of accelerator TMTD, accelerator TETD and accelerator CZ in a mass ratio of 1:1:2.

[0042] The preparation method of the above-mentioned self-adhesive EPDM rubber material after vulcanization in this embodiment includes the following steps: weigh each raw material according to the weight parts, place EPDM raw rubber, modified resin, tackifying resin and polyester plasticizer in a two-roll mill for plasticizing, then add porous nano carbon balls, nano zinc oxide, stearic acid and antioxidant and mix for 4 minutes, finally add vulcanizing agent and accelerator and mix evenly, and vulcanize at 145°C for 12 minutes to obtain the EPDM rubber material.

[0043] Example 2

[0044] This embodiment provides an EPDM rubber material with self-adhesive properties after vulcanization. The EPDM rubber material comprises the following components in parts by weight: 80 parts EPDM raw rubber, 5 parts modified resin, 5 parts tackifying resin, 16 parts porous nano carbon spheres, 8 parts polyester plasticizer, 4 parts nano zinc oxide, 2 parts stearic acid, 1 part antioxidant, 1.5 parts accelerator, and 1 part vulcanizing agent.

[0045] Furthermore, the vinyl content of the EPDM raw rubber is 52%.

[0046] Furthermore, the EPDM rubber material also includes 15 parts of epoxy natural rubber and 6 parts of maleic anhydride-grafted ethylene vinyl acetate copolymer.

[0047] Furthermore, the preparation method of the modified resin includes the following steps: Aryl phenolic resin (MEH-7800S) and anhydrous potassium carbonate at a mass ratio of 1.5:1 are added to 150 mL of N,N-dimethylformamide. After purging with nitrogen, allyl bromide (the mass ratio of aryl phenolic resin to allyl bromide is 1:0.6) is added dropwise and stirred thoroughly. The temperature is raised to 85°C and the reaction is carried out overnight. The filtrate is then filtered and rotary evaporated. The concentrated rotary evaporated liquid is added to deionized water and stirred to disperse. The liquid is then extracted multiple times with dichloromethane. The extract is rotary evaporated and placed in a vacuum oven to remove the solvent, thus obtaining the modified resin.

[0048] Furthermore, the preparation method of the porous carbon nanospheres includes the following steps:

[0049] A1. Add 1g of resorcinol to a mixture of ammonia and ethanol at 60℃ and stir until homogeneous. Then add 1.4mL of formaldehyde solution, keep warm and stir for 20h. After centrifugation, dissolve the product in deionized water and disperse it evenly to obtain a dispersion with a concentration of 5g / L.

[0050] A2. Add 10 mL of dispersion to a mixture of ammonia and ethanol and stir until homogeneous. Then add 0.3 g of hexadecyltrimethylammonium bromide and stir for 1.5 h. Add 1 mL of ethyl silicate and continue stirring for 3 h. After centrifugation, washing and drying, the crude product is obtained.

[0051] A3. The crude product was kept at 400℃ for 1.5h, and then kept at 900℃ for 1.5h. The calcined product was added to 20% hydrofluoric acid and stirred for 24h. After the calcination, the porous carbon nanospheres were obtained by centrifugation, washing and drying.

[0052] Furthermore, in step A1, the mass ratio of ammonia, anhydrous ethanol, and water in the ammonia-water and ethanol-water mixture is 0.3:8:48. In step A2, the mass ratio of ammonia, anhydrous ethanol, and water in the ammonia-water and ethanol-water mixture is 0.3:40:50.

[0053] Furthermore, the tackifying resin is a compound of terpene phenolic resin 801L, styrene-modified C9 petroleum resin and octylphenolic tackifying resin in a mass ratio of 3:4:2.

[0054] Furthermore, the preparation method of the polyester plasticizer includes the following steps: succinic acid, hexanediol, and 3-chloro-1,2-hexanediol are added to a reaction vessel containing toluene, nitrogen gas is introduced to purge the air, the temperature of the reaction vessel is raised to 105-110°C and stirred evenly, then 0.05 wt% tetrabutyl titanate is added, the temperature is raised to 150°C to carry out an esterification reaction until no water is produced in the reaction system, the temperature is raised again to 190°C to carry out a polycondensation reaction, and the reaction product is purified to obtain the polyester plasticizer.

[0055] Furthermore, the molar ratio of succinic acid, hexanediol, and 3-chloro-1,2-hexanediol is 4.76:4:1.

[0056] Furthermore, the antioxidant is N-(1,3-dimethylbutyl)-N'-phenyl-p-phenylenediamine.

[0057] Furthermore, the vulcanizing agent is sulfur.

[0058] Furthermore, the accelerator is a compound of accelerator TMTD, accelerator TETD and accelerator CZ in a mass ratio of 1:1:2.

[0059] The preparation method of the above-mentioned self-adhesive EPDM rubber material after vulcanization in this embodiment includes the following steps: weigh each raw material according to the weight parts, place EPDM raw rubber, modified resin, tackifying resin and polyester plasticizer in a two-roll mill for plasticizing, then add porous nano carbon balls, nano zinc oxide, stearic acid and antioxidant and mix for 4 minutes, finally add vulcanizing agent and accelerator and mix evenly, and vulcanize at 145°C for 12 minutes to obtain the EPDM rubber material.

[0060] Example 3

[0061] This embodiment provides an EPDM rubber material with self-adhesive properties after vulcanization. The EPDM rubber material comprises the following components in parts by weight: 90 parts EPDM raw rubber, 6 parts modified resin, 8 parts tackifying resin, 20 parts porous nano carbon spheres, 13 parts polyester plasticizer, 5 parts nano zinc oxide, 3 parts stearic acid, 1.8 parts antioxidant, 2 parts accelerator, and 2 parts vulcanizing agent.

[0062] Furthermore, the vinyl content of the EPDM raw rubber is 55%.

[0063] Furthermore, the EPDM rubber material also includes 16 parts of epoxy natural rubber and 6 parts of maleic anhydride-grafted ethylene vinyl acetate copolymer.

[0064] Furthermore, the preparation method of the modified resin includes the following steps: Aryl phenolic resin MEH-7800S and anhydrous potassium carbonate at a mass ratio of 1.5:1 are added to 150 mL of N,N-dimethylformamide. After purging with nitrogen, allyl bromide (the mass ratio of aryl phenolic resin to allyl bromide is 1:0.6) is added dropwise and stirred thoroughly. The temperature is raised to 85°C and reacted overnight. The filtrate is then filtered and rotary evaporated. The concentrated rotary evaporated liquid is added to deionized water and stirred to disperse. The liquid is then extracted multiple times with dichloromethane. The extract is rotary evaporated and placed in a vacuum oven to remove the solvent, thus obtaining the modified resin.

[0065] Furthermore, the preparation method of porous carbon nanospheres includes the following steps:

[0066] A1. Add 1g of resorcinol to a mixture of ammonia and ethanol at 60℃ and stir until homogeneous. Then add 1.4mL of formaldehyde solution, keep warm and stir for 24h. After centrifugation, dissolve the product in deionized water and disperse it evenly to obtain a dispersion with a concentration of 5g / L.

[0067] A2. Add 10 mL of dispersion to a mixture of ammonia and ethanol and stir until homogeneous. Then add 0.3 g of hexadecyltrimethylammonium bromide and stir for 1.5 h. Add 1 mL of ethyl silicate and continue stirring for 3 h. After centrifugation, washing and drying, the crude product is obtained.

[0068] A3. The crude product was kept at 400℃ for 2 hours, and then kept at 900℃ for 1.5 hours. The calcined product was added to 20% hydrofluoric acid and stirred for 24 hours. After the calcination, the porous carbon nanospheres were obtained by centrifugation, washing and drying.

[0069] Furthermore, in step A1, the mass ratio of ammonia, anhydrous ethanol, and water in the ammonia-water and ethanol-water mixture is 0.3:8:48. In step A2, the mass ratio of ammonia, anhydrous ethanol, and water in the ammonia-water and ethanol-water mixture is 0.3:40:50.

[0070] Furthermore, the tackifying resin is a compound of terpene phenolic resin 801L, styrene-modified C9 petroleum resin and octylphenolic tackifying resin in a mass ratio of 3:4.5:2.

[0071] Furthermore, the preparation method of the polyester plasticizer includes the following steps: succinic acid, hexanediol, and 3-chloro-1,2-hexanediol are added to a reaction vessel containing toluene, nitrogen gas is introduced to purge the air, the temperature of the reaction vessel is raised to 110°C and stirred evenly, then 0.1 wt% tetrabutyl titanate is added, the temperature is raised to 155°C to carry out an esterification reaction until no water is produced in the reaction system, the temperature is raised again to 190°C to carry out a polycondensation reaction, and the reaction product is purified to obtain the polyester plasticizer.

[0072] Furthermore, the molar ratio of succinic acid, hexanediol, and 3-chloro-1,2-hexanediol is 4.76:4.5:1.

[0073] Furthermore, the antioxidant is a compound of octyl diphenylamine and dilaurate thiodipropionate in a mass ratio of 2:1.

[0074] Furthermore, the vulcanizing agent is sulfur.

[0075] Furthermore, the accelerator is a compound of accelerator TMTD, accelerator TETD and accelerator M in a mass ratio of 1:1:2.

[0076] The preparation method of the above-mentioned self-adhesive EPDM rubber material after vulcanization in this embodiment includes the following steps: weigh each raw material according to the weight parts, place EPDM raw rubber, modified resin, tackifying resin and polyester plasticizer in a two-roll mill for plasticizing, then add porous nano carbon balls, nano zinc oxide, stearic acid and antioxidant and mix for 6 minutes, finally add vulcanizing agent and accelerator and mix evenly, and vulcanize at 160°C for 12 minutes to obtain the EPDM rubber material.

[0077] Comparative Example 1

[0078] The difference between this comparative example and Example 2 is that this comparative example uses an aralkyl-type phenolic resin instead of the modified resin in Example 2.

[0079] Comparative Example 2

[0080] The difference between this comparative example and Example 2 is that commercially available carbon black is used in this comparative example instead of the porous carbon nanospheres in Example 2.

[0081] Comparative Example 3

[0082] The difference between this comparative example and Example 2 is that this comparative example uses Taiwan Chang Chun Chemical Co., Ltd. polyester plasticizer D-1050 instead of the polyester plasticizer in Example 2.

[0083] In this invention, the EPDM test pieces prepared in Examples 1-3 and Comparative Examples 1-3 were tested for hardness, tensile strength, elongation at break, tear strength, self-adhesion, and oil exudation. Hardness was tested according to GB / T 531-2008 standard, tensile strength and elongation at break were tested according to GB / T 528-2009 standard, tear strength was tested according to GB / T 529-2008 standard, and self-adhesion was tested according to GB / T2791-1995 standard. The oil exudation test involved placing the EPDM test piece (120mm*120mm*2mm) on A4 paper and allowing it to stand for 30 days; the depth of the oil stain on the A4 paper surface was used to determine its oil exudation properties. The test results are shown in the table below:

[0084]

[0085] As shown in the table above, the EPDM rubber material prepared by this invention exhibits good overall mechanical properties, strong self-adhesion, and no oil separation. To further evaluate the heat aging resistance of this EPDM rubber material, the EPDM specimens prepared in Example 2 were aged in a 150℃ oven for 72 hours. Tensile strength and elongation at break were then tested on the aged specimens. The results showed that the tensile strength of the aged specimens was 16.5 MPa, and the elongation at break was 558%.

[0086] The specific embodiments described above are further illustrations of the technical solution and beneficial effects of the present invention, and are not intended to limit the implementation methods. For those skilled in the art, any obvious substitutions without departing from the concept of the present invention are within the protection scope of the present invention.

Claims

1. An EPDM rubber material that exhibits self-adhesion after vulcanization, characterized in that: The EPDM rubber material comprises the following components in parts by weight: 70-90 parts EPDM raw rubber, 3-7 parts modified resin, 2-9 parts tackifying resin, 10-25 parts porous nano carbon spheres, 6-15 parts polyester plasticizer, 3-6 parts nano zinc oxide, 1-4 parts stearic acid, 0.5-2 parts antioxidant, 0.5-2 parts accelerator, and 0.5-3 parts vulcanizing agent; The EPDM rubber material also includes 10-20 parts of epoxy natural rubber and 3-8 parts of maleic anhydride-grafted ethylene vinyl acetate copolymer. The preparation method of the modified resin includes the following steps: adding aralkyl phenolic resin and anhydrous potassium carbonate to N,N-dimethylformamide, purging with nitrogen gas, adding allyl bromide dropwise and stirring thoroughly, raising the temperature to 80-85℃ and reacting overnight, then filtering and taking the filtrate for rotary evaporation, adding the concentrated rotary evaporation solution to deionized water and stirring to disperse, then extracting multiple times with DCN, rotary evaporating the extract, and placing it in a vacuum oven to remove the solvent, thereby obtaining the modified resin; The preparation method of the polyester plasticizer includes the following steps: succinic acid, hexanediol, and 3-chloro-1,2-hexanediol are added to a reaction vessel containing toluene, nitrogen gas is introduced to purge the air, the temperature of the reaction vessel is raised to 105-110℃ and stirred evenly, then 0.05wt% tetrabutyl titanate is added, the temperature is raised to 150℃ for esterification reaction until no water is produced in the reaction system, the temperature is raised to 190℃ again for polycondensation reaction, and the reaction product is purified to obtain the polyester plasticizer; The method for preparing the porous carbon nanospheres includes the following steps: A1. Add resorcinol to a mixture of ammonia and ethanol at 55-60℃ and stir until homogeneous. Then add formaldehyde solution, keep warm and stir for 12-24 hours. After centrifugation, dissolve the product in deionized water and disperse it evenly to obtain a dispersion. A2. Add the dispersion to the mixture of ammonia and ethanol and stir until homogeneous. Then add hexadecyltrimethylammonium bromide and stir for 1-1.5 hours. Then add ethyl silicate and continue stirring for 2.5-3 hours. After centrifugation, washing and drying, the crude product is obtained. A3. The crude product is kept at 380-400℃ for 1.5-2 hours, and then kept at 800-900℃ for 1-1.5 hours. The calcined product is added to hydrofluoric acid and stirred for 20-24 hours. After the process, the porous carbon nanospheres are obtained by centrifugation, washing and drying.

2. The EPDM rubber material with self-adhesive properties after vulcanization according to claim 1, characterized in that: The vinyl content of the EPDM raw rubber is 50-60%.

3. The EPDM rubber material with self-adhesive properties after vulcanization according to claim 1, characterized in that: The tackifying resin is at least one of terpene phenolic resin, C9 petroleum resin, octylphenolic tackifying resin, and polymerized rosin.

4. The EPDM rubber material with self-adhesive properties after vulcanization according to claim 1, characterized in that: The antioxidant is at least one of octyl diphenylamine, dilaurate thiodipropionate, N-isopropyl-N'-phenyl-p-phenylenediamine, and N-(1,3-dimethylbutyl)-N'-phenyl-p-phenylenediamine.

5. The EPDM rubber material with self-adhesive properties after vulcanization according to claim 1, characterized in that: The vulcanizing agent is sulfur or diisopropylbenzene peroxide.

6. The EPDM rubber material with self-adhesive properties after vulcanization according to claim 1, characterized in that: The accelerator is at least one of accelerator TMTD, accelerator TETD, accelerator CZ, and accelerator M.

7. The method for preparing the self-adhesive EPDM rubber material after vulcanization as described in any one of claims 1-6, characterized in that: Includes the following steps: Weigh each raw material according to the weight proportions, place the EPDM raw rubber, tackifying resin and polyester plasticizer in a two-roll mill for plasticizing, then add porous nano carbon balls, nano zinc oxide, stearic acid and antioxidant and mix for 3-6 minutes, finally add vulcanizing agent and accelerator and mix evenly, vulcanize at 140-160℃ for 8-12 minutes to obtain the EPDM rubber material.

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