Recyclable conductive silicone rubber and preparation method thereof

Abstract

The invention relates to the technical field of electromagnetic shielding materials, in particular to recyclable conductive silicone rubber and a preparation method thereof. The recyclable conductive silicone rubber comprises the following raw materials in parts by weight: 15-30 parts of silicone rubber, 1-5 parts of white carbon black, 5-15 parts of vinyl silicone oil, 35-50 parts of a conductive filler, 15-40 parts of a modified conductive reclaimed material, 0.1-1 part of a coupling agent and 1-5 parts of a vulcanizing agent. In the recyclable conductive silicone rubber provided by the invention, the white carbon black assists in constructing a conductive network, the conductive efficiency is improved, the dispersion of the conductive powder and the conductive recycled material is facilitated, the crosslinking density and strength of the conductive silicone rubber are increased by the coupling agent, and the wettability of the conductive recycled material and the silicone rubber is increased by using the vinyl silicone oil and modifying the conductive recycled material; the filling amount of the conductive recycled material is increased, high conductivity and battery shielding effectiveness are ensured, the production cost is reduced, the mechanical property is reserved, and the use scene of the conductive silicone rubber is expanded.

Description

Technical Field

[0001] The invention relates to the technical field of electromagnetic shielding materials, and in particular to a recyclable conductive silicone rubber and a preparation method thereof. Background Art

[0002] At present, with the continuous development of my country's communications, aerospace, new energy vehicles and other fields, electromagnetic interference and other problems have become increasingly prominent, and the demand for the electromagnetic shielding function of conductive rubber is also increasing. Conductive rubber needs to have excellent conductivity, so it needs to be filled with more conductive fillers. The price of conductive metal powder fillers remains high. Using conductive silicone rubber recycled materials to fill and replace part of the conductive metal fillers can save costs and reduce the pollution of air, water, soil and other human living environments caused by waste conductive rubber. However, conductive recycled materials have poor wettability with rubber, are not easy to disperse in the rubber matrix, and have poor conductivity, which often leads to poor processing performance of the mixed rubber, a sharp increase in the hardness of the vulcanized rubber, increased resistance, poor electromagnetic shielding performance, and difficulty in filling more conductive recycled materials.

[0003] Therefore, the prior art still needs to be improved and developed. Summary of the invention

[0004] In view of the above-mentioned deficiencies in the prior art, the purpose of the present invention is to provide a recyclable conductive silicone rubber and a preparation method thereof, aiming to solve the problem that conductive silicone rubber prepared by mixing conductive recycled materials with rubber has poor conductivity and electromagnetic shielding properties and pollutes the environment.

[0005] The technical solution of the present invention is as follows:

[0006] The first aspect of the present invention provides a recyclable conductive silicone rubber, comprising the following raw materials in parts by weight:

[0007] 15-30 parts of silicone rubber, 1-5 parts of white carbon black, 5-15 parts of vinyl silicone oil, 35-50 parts of conductive filler, 15-40 parts of modified conductive recycled material, 0.1-1 parts of coupling agent and 1-5 parts of vulcanizing agent.

[0008] Optionally, the silicone rubber is one or more of methyl silicone rubber, methyl vinyl silicone rubber, ethyl vinyl silicone rubber and methyl phenyl vinyl silicone rubber.

[0009] Optionally, the silica is one of fumed silica and precipitated silica.

[0010] Optionally, the vinyl silicone oil is selected from one or more vinyl silicone oils having a viscosity of 100 to 15000 cs.

[0011] Optionally, the conductive filler is at least one of silver powder, silver-coated copper powder, silver-coated aluminum powder, silver-coated glass beads, nickel powder and nickel-coated graphite;

[0012] Optionally, the modified conductive recycled material is obtained by dispersing waste conductive silicone rubber in a solvent after crushing, grinding and sieving, adding a coupling agent and water for stirring reaction, wherein the waste conductive silicone rubber is at least one of the conductive silicone rubbers filled with the conductive filler, and the solvent is any one of methanol, ethanol, propanol, butanol, ethyl acetate, 1,2-propylene glycol methyl ether acetate (PGMEA), and ether solvents.

[0013] Optionally, the coupling agent is at least one selected from a silane coupling agent, a titanate coupling agent, an aluminate coupling agent, a bimetallic coupling agent, a phosphate coupling agent, and a borate coupling agent.

[0014] Optionally, the vulcanizing agent is at least one of 2,5-dimethyl-2,5-di(tert-butylperoxy)hexane, 2,4-dichlorobenzoyl peroxide, benzoyl peroxide, tert-butyl perbenzoate, 1,1-bis(tert-butylperoxy)-3,3,5-trimethylcyclohexane, di-tert-butyl peroxide and diisopropylbenzene peroxide.

[0015] The second aspect of the present invention provides a method for preparing the recyclable conductive silicone rubber, comprising the steps of:

[0016] S1, mixing silicone rubber and white carbon black in a kneader to obtain a base material;

[0017] S2, dividing the conductive filler into two parts, adding one part of the conductive filler to the base material, and performing vacuum kneading to obtain a first mixed product; adding the second part of the conductive filler and silicone oil to the first mixed product, and performing vacuum kneading to obtain a second mixed product;

[0018] S3, adding modified conductive recycled material to the second mixture, performing vacuum mixing to obtain a third mixture, adding a coupling agent and a vulcanizing agent after cooling, mixing to obtain a conductive mixed rubber, and obtaining the conductive silicone rubber after molding or extrusion.

[0019] In step S1, optionally, the mixing temperature is 120-180°C, and the mixing time is 2-4 hours.

[0020] In step S2, optionally, the temperature of the vacuum mixing is 120-180°C, and the time of the vacuum mixing is 3-4 hours.

[0021] In step S3, optionally, the temperature of the vacuum mixing is 120-180° C., and the time of the vacuum mixing is 2-8 hours.

[0022] In step S3, optionally, the molding pressure is 20000-100000 kg, the molding temperature is 140-185° C., and the molding time is 4-10 min; or, the extrusion pressure is 1000-2000 kg / cm 2 The extrusion temperature is 200-400° C., and the extrusion speed is 5-20 M / h.

[0023] Optionally, the temperature of the secondary vulcanization is 180° C. to 200° C., and the vulcanization time is 2 to 4 hours.

[0024] Beneficial effects:

[0025] The present invention provides a recyclable conductive silicone rubber and a preparation method thereof. The solid silicone rubber is mixed with white carbon black and vinyl silicone oil, and filled with conductive powder and modified conductive recycled material. The solid silicone rubber has the advantages of high temperature resistance, cold resistance, solvent resistance and chemical resistance. The conductive powder can be filled to have excellent high conductivity. White carbon black can assist in the construction of a conductive network, improve the conductive efficiency of the conductive network, and improve the dispersibility of the conductive powder and the conductive recycled material. The coupling agent can increase the crosslinking density of the conductive silicone rubber and improve the strength of the silicone rubber. The conductive recycled material is grafted and modified by using vinyl silicone oil and a silane coupling agent, which improves the wettability of the conductive recycled material and the silicone rubber, increases the filling amount of the conductive recycled material, and reduces the production cost and environmental pollution while ensuring high conductivity and excellent electromagnetic shielding performance. The processing performance of the conductive silicone rubber is improved, and the excellent mechanical properties of the original silicone rubber can be maintained, thereby expanding the use scenarios of the conductive silicone rubber. DETAILED DESCRIPTION

[0026] The present invention provides a recyclable conductive silicone rubber and a preparation method thereof. To make the purpose, technical solution and effect of the present invention clearer and more specific, the present invention is further described in detail below. It should be understood that the specific embodiments described herein are only used to explain the present invention and are not used to limit the present invention.

[0027] Unless otherwise defined, all technical terms and scientific terms used herein have the same meaning as those commonly understood by those skilled in the art of the present invention. The terms used in the specification of the present invention herein are only for the purpose of describing specific embodiments and are not intended to limit the present invention.

[0028] The embodiment of the present invention provides a recyclable conductive silicone rubber, comprising the following raw materials in parts by weight:

[0029] 15-30 parts of silicone rubber, 1-5 parts of white carbon black, 5-15 parts of vinyl silicone oil, 35-50 parts of conductive filler, 15-40 parts of modified conductive recycled material, 0.1-1 parts of coupling agent and 1-5 parts of vulcanizing agent.

[0030] In some embodiments, the silicone rubber is one or more of methyl silicone rubber, methyl vinyl silicone rubber, ethyl vinyl silicone rubber, and methyl phenyl vinyl silicone rubber.

[0031] In some embodiments, the silica is one of fumed silica and precipitated silica.

[0032] In some embodiments, the vinyl silicone oil is selected from one or more vinyl silicone oils having a viscosity of 100 to 15000 cs.

[0033] In some embodiments, the conductive filler is at least one of silver powder, silver-coated copper powder, silver-coated aluminum powder, silver-coated glass beads, nickel powder, and nickel-coated graphite;

[0034] In some embodiments, the modified conductive recycled material is obtained by crushing, grinding, sieving, dispersing the waste conductive silicone rubber in a solvent, adding a coupling agent and water for stirring reaction, wherein the waste conductive silicone rubber is at least one of the conductive silicone rubbers filled with the conductive filler (one or more of silver powder, silver-coated copper powder, silver-coated aluminum powder, silver-coated glass beads, nickel powder or nickel-coated graphite), and the solvent is any one of methanol, ethanol, propanol, butanol, ethyl acetate, PGMEA, and ether solvents.

[0035] The modified conductive recycled material obtained by grafting the conductive recycled material with a coupling agent in the embodiment of the present invention can improve the wettability of the conductive recycled material with silicone rubber, increase the filling amount of the conductive recycled material, and thus enhance the conductivity and electromagnetic shielding effectiveness of the conductive silicone rubber.

[0036] In some embodiments, the coupling agent is at least one selected from a silane coupling agent, a titanate coupling agent, an aluminate coupling agent, a bimetallic coupling agent, a phosphate coupling agent, and a borate coupling agent.

[0037] In some embodiments, the vulcanizing agent is at least one of 2,5-dimethyl-2,5-di(tert-butylperoxy)hexane, 2,4-dichlorobenzoyl peroxide, benzoyl peroxide, tert-butyl perbenzoate, 1,1-bis(tert-butylperoxy)-3,3,5-trimethylcyclohexane, di-tert-butyl peroxide and diisopropylbenzene peroxide.

[0038] The embodiment of the present invention further provides a method for preparing the recyclable conductive silicone rubber, comprising the steps of:

[0039] S1, mixing silicone rubber and white carbon black in a kneader to obtain a base material;

[0040] S2, dividing the conductive filler into two parts, adding one part of the conductive filler to the base material, and performing vacuum kneading to obtain a first mixed product; adding the second part of the conductive filler and silicone oil to the first mixed product, and performing vacuum kneading to obtain a second mixed product;

[0041] S3, adding modified conductive recycled material to the second mixture, performing vacuum mixing to obtain a third mixture, adding a coupling agent and a vulcanizing agent after cooling, mixing to obtain a conductive mixed rubber, and obtaining the conductive silicone rubber after molding or extrusion.

[0042] In step S1, in some embodiments, the mixing temperature is 120-180° C., and the mixing time is 2-4 hours.

[0043] In step S2, in some embodiments, the temperature of the vacuum mixing is 120-180° C., and the time of the vacuum mixing is 3-4 hours.

[0044] In step S3, in some embodiments, the temperature of the vacuum mixing is 120-180° C., and the time of the vacuum mixing is 2-8 hours.

[0045] In step S3, in some embodiments, the molding pressure is 20000-100000 kg, the molding temperature is 140-185° C., and the molding time is 4-10 min; or, the extrusion pressure is 1000-2000 kg / cm 2 The extrusion temperature is 200-400° C., and the extrusion speed is 5-20 M / h.

[0046] In some embodiments, the temperature of the secondary vulcanization is 180° C. to 200° C., and the vulcanization time is 2 to 4 hours.

[0047] The following describes it in detail through specific embodiments.

[0048] Example 1

[0049] The conductive silicone rubber prepared in this embodiment includes the following raw materials in parts by weight: 30 parts of methyl vinyl silicone rubber (the molar percentage of vinyl in the methyl vinyl silicone rubber is 0.1%), 0.9 parts of white carbon black (with a specific surface area of ​​180 to 250 m 2 / g), 6 parts of vinyl silicone oil (viscosity 30000cs), 52 parts of conductive nickel carbon powder (average particle size about 100μm), 10 parts of modified recycled conductive nickel carbon silicone rubber, 0.1 parts of silane coupling agent, and 1 part of vulcanizing agent 2,5-dimethyl-2,5-di(tert-butylperoxy)hexane.

[0050] The preparation method of conductive silicone rubber comprises the following steps:

[0051] (1) Grind the waste conductive silicone rubber with a pulverizer and a grinder, pass through a sieve, and obtain 0.6 mm fine powder. Disperse the fine powder in a solvent, slowly add a silane coupling agent and deionized water, stir at room temperature for 6 hours, filter, collect the solid product, wash with deionized water or alcohol, and dry to obtain the modified conductive recycled material.

[0052] (2) 30 parts of methyl vinyl silicone rubber were put into a kneader and mixed with white carbon black to obtain a base material.

[0053] (3) Dividing the conductive powder into two parts; gradually adding the first part of the conductive powder to the base material in step (2), mixing and kneading, and kneading uniformly to obtain a first mixed rubber; adding the second part of the conductive powder and silicone oil to the first mixed material, vacuum kneading for 5 minutes, to obtain a second mixed material.

[0054] (4) Add 55 parts of conductive recycled material and 0.1 parts of silane coupling agent to the second mixed rubber in step (3), and mix them in a vacuum for 15 minutes to obtain a third mixed material.

[0055] (5) Add 1 part of vulcanizing agent to the rubber mixture in step (4), and mix well to obtain a conductive rubber mixture.

[0056] (6) The mixed rubber in step (5) is placed in a molding machine with a molding pressure of 20,000 to 100,000 kg, a molding temperature of 175° C., and a molding time of 5 min to obtain a conductive silicone rubber specimen with a thickness of 2 mm. The specimen is post-cured at 180° C. for 2 h.

[0057] Example 2

[0058] The conductive silicone rubber prepared in this embodiment includes the following raw materials in parts by weight: 27 parts of methyl vinyl silicone rubber (the molar percentage of vinyl in the methyl vinyl silicone rubber is 0.1%), 0.9 parts of white carbon black (with a specific surface area of ​​180 to 250 m 2 / g), 6 parts of vinyl silicone oil (viscosity 30000cs), 46 parts of conductive nickel carbon powder (average particle size about 100μm), 20 parts of modified recycled conductive nickel carbon silicone rubber, 0.1 parts of silane coupling agent, and 1 part of vulcanizing agent 2,5-dimethyl-2,5-di(tert-butylperoxy)hexane.

[0059] The preparation method of conductive silicone rubber comprises the following steps:

[0060] (1) Grind the waste conductive silicone rubber with a pulverizer and a mill, pass through a sieve, and obtain 0.6 mm fine powder. Disperse the fine powder in a solvent, slowly add a silane coupling agent and deionized water, stir at room temperature for 6 hours, filter, collect the solid product, wash with deionized water or alcohol, and dry to obtain the modified conductive recycled material.

[0061] (2) 27 parts of methyl vinyl silicone rubber were put into a kneader and mixed with white carbon black to obtain a base material;

[0062] (3) dividing the conductive powder into two parts; gradually adding the first part of the conductive powder to the base material in step (2), mixing and kneading, and kneading uniformly to obtain a first mixed rubber; adding the second part of the conductive powder and vinyl silicone oil to the first mixed material, and mixing in a vacuum for 5 minutes to obtain a second mixed material;

[0063] (4) Add 46 parts of conductive recycled material and 0.1 parts of silane coupling agent to the second mixed rubber in step (3), and mix them in a vacuum for 15 minutes to obtain a third mixed material.

[0064] (5) adding 1 part of a vulcanizing agent to the rubber mixture in step (4), and mixing the mixture evenly to obtain a conductive rubber mixture;

[0065] (6) The mixed rubber in step (5) is placed in a molding machine with a molding pressure of 20,000 to 100,000 kg, a molding temperature of 175° C., and a molding time of 5 min to obtain a conductive silicone rubber specimen with a thickness of 2 mm. The specimen is post-cured at 180° C. for 2 h.

[0066] Example 3

[0067] The conductive silicone rubber prepared in this embodiment includes the following raw materials in parts by weight: 20 parts of methyl vinyl silicone rubber (the molar percentage of vinyl in the methyl vinyl silicone rubber is 0.1%), 0.9 parts of white carbon black (with a specific surface area of ​​180 to 250 m 2 / g), 8 parts of vinyl silicone oil (viscosity 30000cs), 40 parts of conductive nickel carbon powder (average particle size about 100μm), 30 parts of modified recycled conductive nickel carbon silicone rubber, 0.1 parts of silane coupling agent, and 1 part of vulcanizing agent 2,5-dimethyl-2,5-di(tert-butylperoxy)hexane.

[0068] The preparation method of conductive silicone rubber comprises the following steps:

[0069] (1) Grind the waste conductive silicone rubber with a pulverizer and a grinder, pass through a sieve, and obtain 0.6 mm fine powder. Disperse the fine powder in a solvent, slowly add a silane coupling agent and deionized water, stir at room temperature for 6 hours, filter, collect the solid product, wash with deionized water or alcohol, and dry to obtain the modified conductive recycled material.

[0070] (2) 27 parts of methyl vinyl silicone rubber were put into a kneader and mixed with white carbon black to obtain a base material;

[0071] (3) dividing the conductive powder into two parts; gradually adding the first part of the conductive powder to the base material in step (2), mixing and kneading, and kneading uniformly to obtain a first mixed rubber; adding the second part of the conductive powder and vinyl silicone oil to the first mixed material, and mixing in a vacuum for 5 minutes to obtain a second mixed material;

[0072] (4) Add 40 parts of conductive recycled material and 0.1 parts of silane coupling agent to the second mixed rubber in step (3), and mix them in a vacuum for 15 minutes to obtain a third mixed material.

[0073] (5) adding 1 part of a vulcanizing agent to the rubber mixture in step (4), and mixing the mixture evenly to obtain a conductive rubber mixture;

[0074] (6) The mixed rubber in step (5) is placed in a molding machine with a molding pressure of 20,000 to 100,000 kg, a molding temperature of 175° C., and a molding time of 5 min to obtain a conductive silicone rubber specimen with a thickness of 2 mm. The specimen is post-cured at 180° C. for 2 h.

[0075] Example 4

[0076] The conductive silicone rubber prepared in this embodiment includes the following raw materials in parts by weight: 15 parts of methyl vinyl silicone rubber (the molar percentage of vinyl in the methyl vinyl silicone rubber is 0.1%), 15 parts of methyl phenyl vinyl silicone rubber, 0.9 parts of white carbon black (with a specific surface area of ​​180 to 250 m 2 / g), 6 parts of vinyl silicone oil (viscosity 30000cs), 52 parts of conductive nickel carbon powder (average particle size about 100μm), 10 parts of modified recycled conductive nickel carbon silicone rubber, 0.1 parts of silane coupling agent, and 1 part of vulcanizing agent 2,5-dimethyl-2,5-di(tert-butylperoxy)hexane.

[0077] The preparation method of conductive silicone rubber comprises the following steps:

[0078] (1) Grind the waste conductive silicone rubber with a pulverizer and a grinder, pass through a sieve, and obtain 0.6 mm fine powder. Disperse the fine powder in a solvent, slowly add a silane coupling agent and deionized water, stir at room temperature for 6 hours, filter, collect the solid product, wash with deionized water or alcohol, and dry to obtain the modified conductive recycled material.

[0079] (2) taking 15 parts of methyl vinyl silicone rubber and 15 parts of methyl phenyl vinyl silicone rubber, putting them into a kneader and mixing them with white carbon black to obtain a base material;

[0080] (3) dividing the conductive powder into two parts; gradually adding the first part of the conductive powder to the base material in step (2), mixing and kneading, and kneading uniformly to obtain a first mixed rubber; adding the second part of the conductive powder and vinyl silicone oil to the first mixed material, and mixing in a vacuum for 5 minutes to obtain a second mixed material;

[0081] (4) Add 55 parts of conductive recycled material and 0.1 parts of silane coupling agent to the second mixed rubber in step (3), and mix them in a vacuum for 15 minutes to obtain a third mixed material.

[0082] (5) adding 1 part of a vulcanizing agent to the rubber mixture in step (4), and mixing the mixture evenly to obtain a conductive rubber mixture;

[0083] (6) The mixed rubber in step (5) is placed in a molding machine with a molding pressure of 20,000 to 100,000 kg, a molding temperature of 175° C., and a molding time of 5 min to obtain a conductive silicone rubber specimen with a thickness of 2 mm. The specimen is post-cured at 180° C. for 2 h.

[0084] Comparative Example 1

[0085] A conductive silicone rubber is prepared, comprising the following raw materials in parts by weight: 36 parts of methyl vinyl silicone rubber (the molar percentage of vinyl in the methyl vinyl silicone rubber is 0.1%), 0.9 parts of white carbon black (with a specific surface area of ​​180 to 250 m 2 / g), 52 parts of conductive nickel carbon powder (average particle size of about 100 μm), 10 parts of modified and recycled conductive nickel carbon silicone rubber, 0.1 parts of silane coupling agent, and 1 part of vulcanizing agent 2,5-dimethyl-2,5-di(tert-butylperoxy)hexane.

[0086] The preparation method of conductive silicone rubber comprises the following steps:

[0087] (1) Grind the waste conductive silicone rubber with a pulverizer and a grinder, pass through a sieve, and obtain 0.6 mm fine powder. Disperse the fine powder in a solvent, slowly add a silane coupling agent and deionized water, stir at room temperature for 6 hours, filter, collect the solid product, wash with deionized water or alcohol, and dry to obtain the modified conductive recycled material.

[0088] (2) 30 parts of methyl vinyl silicone rubber were put into a kneader and mixed with white carbon black to obtain a base material;

[0089] (3) dividing the conductive powder into two parts; gradually adding the first part of the conductive powder to the base material in step (2), mixing and kneading, and kneading uniformly to obtain a first mixed rubber; adding the second part of the conductive powder to the first mixed material, vacuum kneading for 5 minutes, to obtain a second mixed material;

[0090] (4) Add 55 parts of conductive recycled material and 0.1 parts of silane coupling agent to the second mixed rubber in step (3), and mix them in a vacuum for 15 minutes to obtain a third mixed material.

[0091] (5) adding 1 part of a vulcanizing agent to the rubber mixture in step (4), and mixing the mixture evenly to obtain a conductive rubber mixture;

[0092] (6) The mixed rubber in step (5) is placed in a molding machine with a molding pressure of 20,000 to 100,000 kg, a molding temperature of 175° C., and a molding time of 5 min to obtain a conductive silicone rubber specimen with a thickness of 2 mm. The specimen is post-cured at 180° C. for 2 h.

[0093] The conductive silicone rubbers prepared in Examples 1 to 4 and Comparative Example 1 were tested, and the measured properties are shown in Table 1 below.

[0094] Table 1

[0095]

[0096]

[0097] As can be seen from Table 1, Examples 1 to 3 are conductive silicone rubbers prepared with modified conductive recycled materials having filling amounts of 10%, 20%, and 30%, respectively. It can be seen that with the increase in the filling amount of the modified conductive recycled material, the mechanical properties of the conductive silicone rubber material are slightly reduced, and the shielding effectiveness is also reduced.

[0098] Compared with the conductive silicone rubber in Example 1, part of the methyl vinyl silicone rubber is replaced by methyl phenyl vinyl silicone rubber. It can be seen that the mechanical properties of the material are almost unaffected, the compression permanent deformation rate is reduced, and the aging of the material's temperature cycling shielding effectiveness is also improved.

[0099] Compared with the conductive silicone rubber in Example 1, Comparative Example 1 does not include vinyl silicone oil. Instead, the component of vinyl silicone oil is replaced by methyl vinyl silicone rubber. During the mixing process, the conductive nickel carbon powder and the recycled conductive nickel carbon silicone rubber are difficult to disperse evenly. After compression molding, a large amount of nickel carbon powder falls off the surface of the material. It can be seen from Table 1 that although the conductive properties and shielding effectiveness of the conductive silicone rubber material do not change much, the mechanical properties of the conductive silicone rubber material are reduced, and the hardness increases significantly.

[0100] It should be understood that the application of the present invention is not limited to the above examples. For ordinary technicians in this field, improvements or changes can be made based on the above description. All these improvements and changes should fall within the scope of protection of the claims attached to the present invention.

Claims

1. A recyclable conductive silicone rubber, characterized in that: The preparation is obtained by including the following raw materials in parts by weight: 15-30 parts of silicone rubber, 1-5 parts of white carbon black, 5-15 parts of vinyl silicone oil, 35-50 parts of conductive filler, 15-40 parts of modified conductive recycled material, 0.1-1 parts of coupling agent and 1-5 parts of vulcanizing agent.

2. The recyclable conductive silicone rubber according to claim 1, characterized in that: The silicone rubber is one or more of methyl silicone rubber, methyl vinyl silicone rubber, ethyl vinyl silicone rubber and methyl phenyl vinyl silicone rubber.

3. The recyclable conductive silicone rubber according to claim 1, characterized in that: The white carbon black is one of gas phase white carbon black and precipitated white carbon black.

4. The recyclable conductive silicone rubber according to claim 1, characterized in that: The vinyl silicone oil is selected from one or more vinyl silicone oils having a viscosity of 100 to 15000 cs.

5. The recyclable conductive silicone rubber according to claim 1, characterized in that: The conductive filler is at least one of silver powder, silver-coated copper powder, silver-coated aluminum powder, silver-coated glass beads, nickel powder and nickel-coated graphite; And / or, the modified conductive recycled material is obtained by dispersing waste conductive silicone rubber in a solvent after crushing, grinding and sieving, adding a silane coupling agent and water for stirring reaction, wherein the waste conductive silicone rubber is at least one of the conductive silicone rubbers filled with the conductive filler, and the solvent is any one of methanol, ethanol, propanol, butanol, ethyl acetate, 1,2-propylene glycol methyl ether acetate, and ether solvents.

6. The recyclable conductive silicone rubber according to claim 1, characterized in that: The coupling agent is at least one selected from silane coupling agent, titanate coupling agent, aluminate coupling agent, bimetallic coupling agent, phosphate coupling agent, and borate coupling agent.

7. The recyclable conductive silicone rubber according to claim 1, characterized in that: The vulcanizing agent is at least one of 2,5-dimethyl-2,5-di(tert-butylperoxy)hexane, 2,4-dichlorobenzoyl peroxide, benzoyl peroxide, tert-butyl peroxybenzoate, 1,1-bis(tert-butylperoxy)-3,3,5-trimethylcyclohexane, di-tert-butyl peroxide and diisopropylbenzene peroxide.

8. A method for preparing the recyclable conductive silicone rubber according to claims 1 to 7, characterized in that: Includes steps: S1, mixing silicone rubber and white carbon black in a kneader to obtain a base material; S2, dividing the conductive filler into two parts, adding one part of the conductive filler to the base material, and performing vacuum kneading to obtain a first mixed product; adding a second portion of conductive filler and vinyl silicone oil to the first mixed product, and performing vacuum mixing to obtain a second mixed product; S3, adding modified conductive recycled material to the second mixture, performing vacuum mixing to obtain a third mixture, adding a coupling agent and a vulcanizing agent after cooling, mixing to obtain a conductive mixed rubber, and obtaining the conductive silicone rubber after molding or extrusion.

9. The method for preparing recyclable conductive silicone rubber according to claim 8, characterized in that: In step S1, the mixing temperature is 120-180°C, and the mixing time is 2-4 hours; in step S2, the vacuum mixing temperature is 120-180°C, and the vacuum mixing time is 3-4 hours; in step S3, the vacuum mixing temperature is 120-180°C, and the vacuum mixing time is 2-8 hours.

10. The method for preparing recyclable conductive silicone rubber according to claim 8, characterized in that: In step S3, the molding pressure is 20000-100000 kg, the molding temperature is 140-185° C., and the molding time is 4-10 min; or, the extrusion pressure is 1000-2000 kg / cm 2 , the extrusion temperature is 200-400° C., and the extrusion speed is 5-20 M / h; And / or, the temperature of the secondary vulcanization is 180° C. to 200° C., and the vulcanization time is 2 to 4 hours.

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