EPDM (Ethylene-Propylene-Diene Monomer) rubber material with self-adhesion after vulcanization and preparation method thereof

Abstract

The invention relates to the technical field of production of rubber materials, in particular to an EPDM (Ethylene-Propylene-Diene Monomer) rubber material with self-adhesion after vulcanization and a preparation method thereof. The EPDM rubber material comprises the following components in parts by mass: 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 a polyester plasticizer, 3-6 parts of nano zinc oxide, 1-4 parts of stearic acid, 0.5-2 parts of an anti-aging agent, 0.5-2 parts of an accelerant and 0.5-3 parts of a vulcanizing agent. The EPDM material disclosed by the invention has the characteristics of strong autohension, no oil separation, high mechanical property and good heat-resistant stability. Wherein the modified resin is introduced into the EPDM raw rubber to generate crosslinking with the EPDM raw rubber, and the tackifying resin and the polyester plasticizer are matched for use, so that the mechanical property, heat resistance and autohension of the material are effectively improved; and the oil separation property of the EPDM rubber material is effectively improved by introducing the porous nano carbon spheres.

Description

Technical Field

[0001] The invention relates to the technical field of rubber material production, and in particular to an EPDM rubber material having self-adhesiveness after vulcanization and a preparation method thereof. Background Art

[0002] The vulcanization molding process of most rubber products requires different parts to be bonded together for vulcanization molding, so most rubber formulas need to consider the problem of self-adhesion. Self-adhesion refers to the property of the same unvulcanized mixed rubber surfaces to adhere to each other, and the self-adhesion is caused by the mutual diffusion of molecules on the rubber surface through thermal motion. Among them, ethylene propylene diene monomer rubber (EPDM) is often used for parts such as automobile window seals, radiator hoses, building waterproof membranes, and sealing strips. This type of rubber product requires that the vulcanized EPDM rubber has good self-adhesion, so that it can better bond with other parts or itself, without the need to use a large amount of additional adhesives, and can also play a role in sealing, leak prevention, and heat insulation.

[0003] For EPDM rubber, due to its small number of active groups and weak intermolecular forces, it is difficult to form good self-adhesion after vulcanization. On the other hand, in order to improve the processing performance of the rubber and reduce production costs, plasticizers, softeners, filler oils and other raw materials are usually added in the preparation of rubber products. However, during the vulcanization process, these low molecular weight components may not be fully integrated into the cross-linked network, and some of them migrate to the surface of the product to form a thin layer, which leads to a significant decrease in the self-adhesion of the product. In this regard, it is urgent to propose a solution to improve the self-adhesion of EPDM rubber materials after vulcanization to meet the use requirements of back-end applications. Summary of the invention

[0004] The purpose of the present invention is to solve the above-mentioned deficiencies in the prior art and to provide an EPDM rubber material having self-adhesiveness after vulcanization and a preparation method thereof.

[0005] The purpose of the present invention is achieved through the following technical scheme: an EPDM rubber material with self-adhesiveness after vulcanization, the EPDM rubber material comprising the following components in parts by mass: 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 balls, 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 the present invention, epoxy natural rubber and maleic anhydride grafted ethylene vinyl acetate copolymer are added to the EPDM matrix, and the epoxy group can interact with EPDM and the maleic anhydride grafted ethylene vinyl acetate copolymer, thereby improving the compatibility of the entire reaction system and forming an effective reinforcement network, thereby increasing the crosslinking density of the EPDM material, thereby effectively improving the tensile strength, tear strength and elasticity of the EPDM rubber material, and also helping to enhance the aging resistance of the material.

[0009] Furthermore, the preparation method of the modified resin comprises the following steps: adding aralkyl phenolic resin and anhydrous potassium carbonate to N,N-dimethylformamide, introducing nitrogen to evacuate, adding allyl bromide dropwise thereto and stirring thoroughly, raising the temperature to 80-85°C to react overnight, filtering the filtrate and performing rotary evaporation, adding the rotary evaporation concentrate to deionized water and stirring to disperse, then extracting with dichloromethane for multiple times, rotary evaporating the extract, and placing it in a vacuum oven to remove the solvent, thereby obtaining the modified resin.

[0010] In the present invention, the phenolic resin is modified by the above method so that it contains unsaturated propylene groups, which can react with the double bonds in EPDM, thereby promoting the formation of a cross-linked network between rubber molecular chains, so that the vulcanized EPDM rubber material has better heat resistance stability and mechanical properties; furthermore, active groups are formed on the surface of the material through the cross-linking effect and the interface compatibility is enhanced, thereby significantly improving the self-adhesiveness of the EPDM material.

[0011] Furthermore, the preparation method of porous nanocarbon spheres comprises the following steps:

[0012] A1. Add resorcinol to a mixture of ammonia water and ethanol water at 55-60°C and stir evenly, then add formaldehyde solution, keep warm and stir for 12-24 hours, dissolve the product after centrifugation in deionized water and disperse evenly to obtain a dispersion;

[0013] A2, add 10mL of the dispersion to a mixture of ammonia water and ethanol water and stir evenly, then add hexadecyltrimethylammonium bromide and stir for 1-1.5h, then add ethyl silicate and continue stirring for 2.5-3h, centrifuge, wash and dry to obtain a crude product;

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

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

[0016] In the present invention, the hollow nano-carbon spheres with multiple pores and large specific surface area are prepared by the above scheme, and the particle size is 200-400nm. Due to its abundant pores, it can adsorb small molecules in the matrix, thereby significantly reducing the oil separation of rubber. Furthermore, the porous nano-carbon spheres can be used as a reinforcing agent to improve the mechanical strength and wear resistance of the EPDM rubber material. At the same time, the porous nano-carbon spheres can effectively improve the heat resistance of the EPDM by virtue of their own good thermal stability.

[0017] Furthermore, the tackifying resin is at least one of terpene phenolic resin, C9 petroleum resin, octyl phenolic tackifying resin, and polymerized rosin. As preferred in the present invention, the tackifying resin is compounded with terpene phenolic resin 801L, styrene-modified C9 petroleum resin and octyl phenolic tackifying resin in a mass ratio of 3:4-4.5:2.

[0018] Furthermore, the preparation method of the polyester plasticizer comprises the following steps: adding succinic acid, hexanediol and 3-chloro-1,2-hexanediol into a reaction container filled with toluene, introducing nitrogen to evacuate, raising the temperature of the reaction container to 105-110° C. and stirring evenly, then adding 0.02-0.1wt% of tetrabutyl titanate thereto, continuing to raise the temperature to 145-155° C. for esterification reaction, until no water is produced in the reaction system, raising the temperature again to 188-192° C. for polycondensation reaction, and obtaining the polyester plasticizer after the reaction product is purified.

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

[0021] Furthermore, the antioxidant is at least one of octylated diphenylamine, dilauryl 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 promoter is at least one of promoter TMTD, promoter TETD, promoter CZ and promoter M.

[0024] The present invention also provides a method for preparing the above-mentioned EPDM rubber material with self-adhesiveness after vulcanization, comprising the following steps: weighing each raw material by weight, placing EPDM raw rubber, tackifying resin and polyester plasticizer in an open mill for plasticizing, then adding porous nano-carbon balls, nano-zinc oxide, stearic acid and antioxidant thereto and mixing for 3-6 minutes, finally adding a vulcanizer and an accelerator and mixing evenly, and vulcanizing at 140-160° C. for 8-12 minutes to obtain the EPDM rubber material.

[0025] The beneficial effects of the present invention are as follows: the present invention provides an EPDM rubber material having self-adhesiveness after vulcanization and a preparation method thereof, wherein the EPDM material has the characteristics of strong self-adhesiveness, no oil separation, high mechanical properties and good heat resistance stability. Among them, by introducing a modified resin into the EPDM raw rubber to produce cross-linking therewith, and 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 nano-carbon spheres, the rich pores and large specific surface area thereof can be utilized to play a reinforcing role while also being able to adsorb small molecules precipitated from the matrix, thereby effectively improving the oil separation of the EPDM rubber material. DETAILED DESCRIPTION

[0026] In order to facilitate the understanding of those skilled in the art, the present invention is further described below in conjunction with embodiments, and the contents mentioned in the implementation modes are not intended to limit the present invention.

[0027] Example 1

[0028] The present embodiment provides an EPDM rubber material which has self-adhesiveness after vulcanization, and the EPDM rubber material includes the following components in parts by mass: 70 parts of EPDM raw rubber, 4 parts of modified resin, 3 parts of tackifying resin, 10 parts of porous nano-carbon spheres, 7 parts of polyester plasticizer, 4 parts of nano-zinc oxide, 2 parts of stearic acid, 1 part of antioxidant, 1 part of accelerator, and 0.5 part of 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: adding an aralkyl phenolic resin (MEH-7800S) and anhydrous potassium carbonate in a mass ratio of 1.5:1 to 150mL N,N-dimethylformamide, introducing nitrogen to evacuate, adding allyl bromide (the mass ratio of the aralkyl phenolic resin to allyl bromide is 1:0.6) dropwise thereinto, stirring thoroughly, raising the temperature to 80°C to react overnight, then filtering the filtrate and performing rotary evaporation, adding the rotary evaporation concentrate to deionized water and stirring to disperse, then extracting with dichloromethane for multiple times, rotary evaporating the extract, and placing it in a vacuum oven to remove the solvent, thereby obtaining the modified resin.

[0031] Furthermore, the preparation method of porous nanocarbon spheres comprises the following steps:

[0032] A1. Add 1 g of resorcinol to a mixture of ammonia water and ethanol water at 55°C and stir evenly, then add 1.4 mL of formaldehyde solution, keep warm and stir for 16 hours, dissolve the product after centrifugation in deionized water and disperse evenly to obtain a dispersion with a concentration of 5 g / L;

[0033] A2, add 10mL of the dispersion to a mixture of ammonia water and ethanol water and stir evenly, then add 0.3g of hexadecyltrimethylammonium bromide and stir for 1h, then add 1mL of ethyl silicate and continue stirring for 2.5h, centrifuge, wash and dry to obtain a crude product;

[0034] A3. The crude product is kept at 380°C for 2 hours, and then kept at 800°C for 1 hour. The calcined product is added into 20% hydrofluoric acid and stirred for 20 hours. After the calcination, the porous nano-carbon spheres are obtained by centrifugation, washing and drying.

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

[0036] Furthermore, the tackifying resin is compounded by 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 comprises the following steps: adding succinic acid, hexanediol, and 3-chloro-1,2-hexanediol into a reaction container filled with toluene, introducing nitrogen to evacuate, raising the temperature of the reaction container to 105° C. and stirring evenly, then adding 0.03 wt % of tetrabutyl titanate thereto, continuing to raise the temperature to 145° C. for esterification reaction, until no water is produced in the reaction system, raising the temperature again to 190° C. for polycondensation reaction, and obtaining the polyester plasticizer after purification of the reaction product.

[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 compounded by accelerator TMTD, accelerator TETD and accelerator CZ in a mass ratio of 1:1:2.

[0042] The preparation method of the EPDM rubber material having self-adhesiveness after vulcanization in the present embodiment comprises the following steps: weighing each raw material by weight, placing the EPDM raw rubber, tackifying resin and polyester plasticizer in an open mill for plasticizing, then adding porous nano-carbon spheres, nano-zinc oxide, stearic acid and antioxidant thereto and mixing for 4 minutes, finally adding a vulcanizing agent and an accelerator and mixing evenly, and vulcanizing at 145° C. for 12 minutes to obtain the EPDM rubber material.

[0043] Example 2

[0044] The present embodiment provides an EPDM rubber material which has self-adhesiveness after vulcanization, and the EPDM rubber material includes the following components in parts by mass: 80 parts of EPDM raw rubber, 5 parts of modified resin, 5 parts of tackifying resin, 16 parts of porous nano-carbon spheres, 8 parts of polyester plasticizer, 4 parts of nano-zinc oxide, 2 parts of stearic acid, 1 part of antioxidant, 1.5 parts of accelerator, and 1 part of 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: adding an aralkyl phenolic resin (MEH-7800S) and anhydrous potassium carbonate in a mass ratio of 1.5:1 to 150mL N,N-dimethylformamide, introducing nitrogen to evacuate, adding allyl bromide (the mass ratio of the aralkyl phenolic resin to allyl bromide is 1:0.6) dropwise thereinto, stirring thoroughly, raising the temperature to 85°C to react overnight, then filtering the filtrate and performing rotary evaporation, adding the rotary evaporation concentrate to deionized water and stirring to disperse, then extracting with dichloromethane for multiple times, rotary evaporating the extract, and placing it in a vacuum oven to remove the solvent, thereby obtaining the modified resin.

[0048] Furthermore, the method for preparing the porous nanocarbon spheres comprises the following steps:

[0049] A1. Add 1 g of resorcinol to a mixture of ammonia water and ethanol water at 60°C and stir evenly, then add 1.4 mL of formaldehyde solution, keep warm and stir for 20 hours, dissolve the product after centrifugation in deionized water and disperse evenly to obtain a dispersion with a concentration of 5 g / L;

[0050] A2, add 10mL of the dispersion to a mixture of ammonia water and ethanol water and stir evenly, then add 0.3g of hexadecyltrimethylammonium bromide and stir for 1.5h, then add 1mL of ethyl silicate and continue stirring for 3h, centrifuge, wash and dry to obtain a crude product;

[0051] A3. The crude product is kept at 400°C for 1.5 hours, and then kept at 900°C for 1.5 hours. The calcined product is added into 20% hydrofluoric acid and stirred for 24 hours. After the calcination, the porous nano-carbon spheres are obtained by centrifugation, washing and drying.

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

[0053] Furthermore, the tackifying resin is compounded by 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 comprises the following steps: adding succinic acid, hexanediol and 3-chloro-1,2-hexanediol into a reaction container filled with toluene, introducing nitrogen to evacuate, raising the temperature of the reaction container to 105-110° C. and stirring evenly, then adding 0.05wt% of tetrabutyl titanate thereto, continuing to raise the temperature to 150° C. for esterification reaction, until no water is produced in the reaction system, raising the temperature again to 190° C. for polycondensation reaction, and obtaining the polyester plasticizer after the reaction product is purified.

[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 compounded by accelerator TMTD, accelerator TETD and accelerator CZ in a mass ratio of 1:1:2.

[0059] The preparation method of the EPDM rubber material having self-adhesiveness after vulcanization in the present embodiment comprises the following steps: weighing each raw material by weight, placing the EPDM raw rubber, tackifying resin and polyester plasticizer in an open mill for plasticizing, then adding porous nano-carbon spheres, nano-zinc oxide, stearic acid and antioxidant thereto and mixing for 4 minutes, finally adding a vulcanizing agent and an accelerator and mixing evenly, and vulcanizing at 145° C. for 12 minutes to obtain the EPDM rubber material.

[0060] Example 3

[0061] The present embodiment provides an EPDM rubber material which has self-adhesiveness after vulcanization, and the EPDM rubber material includes the following components in parts by mass: 90 parts of EPDM raw rubber, 6 parts of modified resin, 8 parts of tackifying resin, 20 parts of porous nano-carbon balls, 13 parts of polyester plasticizer, 5 parts of nano-zinc oxide, 3 parts of stearic acid, 1.8 parts of antioxidant, 2 parts of accelerator, and 2 parts of 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 comprises the following steps: adding an aralkyl phenolic resin MEH-7800S and anhydrous potassium carbonate in a mass ratio of 1.5:1 to 150 mL of N,N-dimethylformamide, introducing nitrogen to evacuate, adding allyl bromide (the mass ratio of the aralkyl phenolic resin to allyl bromide is 1:0.6) dropwise thereinto, stirring thoroughly, raising the temperature to 85°C to react overnight, filtering the filtrate and performing rotary evaporation, adding the rotary evaporation concentrate to deionized water, stirring and dispersing, extracting with dichloromethane for multiple times, rotary evaporating the extract, and placing it in a vacuum oven to remove the solvent, thereby obtaining the modified resin.

[0065] Furthermore, the preparation method of porous nano-carbon spheres comprises the following steps:

[0066] A1. Add 1 g of resorcinol to a mixture of ammonia water and ethanol water at 60°C and stir evenly, then add 1.4 mL of formaldehyde solution, keep warm and stir for 24 hours, dissolve the product after centrifugation in deionized water and disperse evenly to obtain a dispersion with a concentration of 5 g / L;

[0067] A2, add 10mL of the dispersion to a mixture of ammonia water and ethanol water and stir evenly, then add 0.3g of hexadecyltrimethylammonium bromide and stir for 1.5h, then add 1mL of ethyl silicate and continue stirring for 3h, centrifuge, wash and dry to obtain a crude product;

[0068] A3. The crude product is kept at 400° C. for 2 hours, and then kept at 900° C. for 1.5 hours. The calcined product is added into 20% hydrofluoric acid and stirred for 24 hours. After the calcination, the porous nano-carbon spheres are obtained by centrifugation, washing and drying.

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

[0070] Furthermore, the tackifying resin is compounded by 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: adding succinic acid, hexanediol, and 3-chloro-1,2-hexanediol to a reaction container filled with toluene, introducing nitrogen to evacuate, raising the temperature of the reaction container to 110° C. and stirring evenly, then adding 0.1wt% of tetrabutyl titanate thereto, continuing to raise the temperature to 155° C. for esterification reaction until no water is produced in the reaction system, and then raising the temperature to 190° C. again for 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 prepared by compounding octylated diphenylamine and dilauryl thiodipropionate in a mass ratio of 2:1.

[0074] Furthermore, the vulcanizing agent is sulfur.

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

[0076] The preparation method of the EPDM rubber material having self-adhesiveness after vulcanization in the present embodiment comprises the following steps: weighing each raw material by weight, placing the EPDM raw rubber, tackifying resin and polyester plasticizer in an open mill for plasticizing, then adding porous nano-carbon spheres, nano-zinc oxide, stearic acid and antioxidant thereto and mixing for 6 minutes, finally adding a vulcanizing agent and an accelerator and mixing evenly, and vulcanizing 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 aralkyl phenolic resin to replace the modified resin in Example 2.

[0079] Comparative Example 2

[0080] The difference between this comparative example and Example 2 is that this comparative example uses commercially available carbon black to replace the porous nano-carbon spheres in Example 2.

[0081] Comparative Example 3

[0082] The difference between this comparative example and Example 2 is that this comparative example uses Taiwan Changchun Chemical Polyester Plasticizer D-1050 to replace the polyester plasticizer in Example 2.

[0083] In the present invention, the EPDM test pieces prepared in the above-mentioned Examples 1-3 and Comparative Examples 1-3 are tested for hardness, tensile strength, elongation at break, tear strength, self-adhesion and oil separation, wherein the hardness is tested according to the GB / T 531-2008 standard, the tensile strength and elongation at break are tested according to the GB / T 528-2009 standard, the tear strength is tested according to the GB / T529-2008 standard, and the self-adhesion is tested according to the GB / T 2791-1995 standard. The oil separation test is to place the EPDM test piece (120mm*120mm*2mm) on A4 paper and let it stand for 30 days, and judge its oil separation according to the depth of the oil print on the surface of the A4 paper. The test results are shown in the following table:

[0084]

[0085]

[0086] It can be seen from the data in the above table that the EPDM rubber material prepared in the present invention has good overall mechanical properties, strong self-adhesion and no oil separation. In order to further evaluate the heat aging resistance of the EPDM rubber material, the present invention places the EPDM test piece prepared in Example 2 in a 150°C oven for aging for 72 hours, and then the tensile strength and elongation at break of the aged test piece are tested. The results show that the tensile strength of the aged test piece is 16.5MPa, and the elongation at break is 558%.

[0087] The above specific embodiments are further explanations of the technical solutions and beneficial effects of the present invention, and are not limitations of the implementation methods. For those skilled in the art, any obvious replacements that do not depart from the concept of the present invention are within the protection scope of the present invention.

Claims

1. An EPDM rubber material having self-adhesiveness after vulcanization, characterized in that: The EPDM rubber material comprises the following components in parts by mass: 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 balls, 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 vulcanizer.

2. The EPDM rubber material having self-adhesiveness 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 having self-adhesiveness after vulcanization according to claim 1, characterized in that: 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.

4. The EPDM rubber material having self-adhesiveness after vulcanization according to claim 1, characterized in that: The preparation method of the modified resin comprises the following steps: adding aralkyl phenolic resin and anhydrous potassium carbonate into N,N-dimethylformamide, introducing nitrogen to evacuate, adding allyl bromide dropwise thereinto and stirring fully, raising the temperature to 80-85°C to react overnight, filtering and taking the filtrate for rotary evaporation, adding the rotary evaporation concentrated liquid into deionized water and stirring and dispersing, extracting with DCN for multiple times, rotary evaporating the extract, and placing it in a vacuum oven to remove the solvent, so as to obtain the modified resin.

5. The EPDM rubber material having self-adhesiveness after vulcanization according to claim 1, characterized in that: The method for preparing the porous nano carbon spheres comprises the following steps: A1. Add resorcinol to a mixture of ammonia water and ethanol water at 55-60°C and stir evenly, then add formaldehyde solution, keep warm and stir for 12-24 hours, dissolve the product after centrifugation in deionized water and disperse evenly to obtain a dispersion; A2, adding the dispersion to a mixture of ammonia water and ethanol water and stirring evenly, then adding hexadecyltrimethylammonium bromide and stirring for 1-1.5h, then adding ethyl silicate and stirring for 2.5-3h, centrifuging, washing and drying to obtain a crude product; A3. The crude product is kept at 380-400°C for 1.5-2h, and then kept at 800-900°C for 1-1.5h. The calcined product is added to hydrofluoric acid and stirred for 20-24h. After the calcination, the porous nano-carbon spheres are obtained by centrifugation, washing and drying.

6. The EPDM rubber material having self-adhesiveness after vulcanization according to claim 1, characterized in that: The tackifying resin is at least one of terpene phenolic resin, C9 petroleum resin, octyl phenolic tackifying resin and polymerized rosin.

7. The EPDM rubber material having self-adhesiveness after vulcanization according to claim 1, characterized in that: The antioxidant is at least one of octylated diphenylamine, dilauryl thiodipropionate, N-isopropyl-N'-phenyl-p-phenylenediamine, and N-(1,3-dimethylbutyl)-N'-phenyl-p-phenylenediamine.

8. The EPDM rubber material having self-adhesiveness after vulcanization according to claim 1, characterized in that: The vulcanizing agent is sulfur or dicumyl peroxide.

9. The EPDM rubber material having self-adhesiveness after vulcanization according to claim 1, characterized in that: The promoter is at least one of promoter TMTD, promoter TETD, promoter CZ and promoter M.

10. The method for preparing the EPDM rubber material having self-adhesiveness after vulcanization according to any one of claims 1 to 9, characterized in that: The following steps are involved: Weigh each raw material by weight, place EPDM raw rubber, tackifying resin and polyester plasticizer in an open mill for plasticizing, then add porous nano carbon spheres, nano zinc oxide, stearic acid and antioxidant and mix for 3-6 minutes, finally add vulcanizing agent and accelerator and mix evenly, and vulcanize at 140-160° C. for 8-12 minutes to obtain the EPDM rubber material.

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