Rubber magnet and preparation method thereof

Abstract

The invention relates to a rubber magnet and a preparation method thereof. The rubber magnet comprises ferrite magnetic powder, a thermoplastic rubber material and a processing aid, the thermoplastic rubber material comprises silicon-based thermoplastic vulcanized rubber. According to the rubber magnet, a thermoplastic rubber material (TPSIV) is selected as an adhesive. The TPSIV is a halogen-free environment-friendly material, shows rubber elasticity at normal temperature, can be plasticized and molded at high temperature, and has the characteristics of vulcanized rubber and thermoplasticity, the magnetic performance of the prepared rubber magnet is not reduced, the hardness and elongation at break are less changed after a high-temperature experiment, and the rubber magnet is more resistant to high-temperature aging, so that the application field of the product is expanded. In the preparation process of the rubber magnet, a vulcanization procedure is not needed, the processing technology is simple, the forming period is short, and leftover materials and old products can be recycled and reprocessed.

Description

Technical Field

[0001] The invention relates to the technical field of permanent magnets, and in particular to a rubber magnet and a preparation method thereof. Background Art

[0002] Rubber magnet is a flexible magnetic material made of bonded ferrite powder and synthetic rubber. It has the characteristics of softness, elasticity and twistability. This material can be made into strips, rolls, sheets, blocks, rings and various complex shapes through extrusion molding, calendering molding, injection molding and other processes. Rubber magnets have been widely used in home appliances, computers, automobiles, micro motors and other industries due to their low energy consumption, high production efficiency, good dimensional consistency, high product freedom, and convenient product size changes.

[0003] At present, there are two main types of adhesives commonly used to prepare rubber magnets, one is chlorinated polyethylene (CPE) adhesive, and the other is nitrile rubber (NBR) adhesive. CPE rubber magnets are easy to prepare, do not require vulcanization, are cheap, and scraps can be recycled, but they have disadvantages such as high halogen content (not meeting EU environmental standards) and poor high temperature resistance (the application temperature is generally below 80°C). NBR rubber magnets do not contain halogens and have an operating temperature of around 100°C, but the processing technology is complicated and requires vulcanization treatment, making them difficult to recycle and reuse.

[0004] Patent CN104200952A discloses a halogen-free, oil-resistant, and high-temperature-resistant flexible ferrite rubber magnet and a preparation method thereof. The patent improves the high-temperature resistance of the system by a method of blending and modifying high-temperature rubber and nitrile rubber, thereby obtaining a halogen-free and high-temperature-resistant rubber magnet. However, this method also requires vulcanization, which has the disadvantages of complex formulas and processing. In addition, the blended rubber may be prone to asynchronous vulcanization of the blended rubber due to different vulcanization mechanisms, types of vulcanizing agents, and amounts, thereby affecting product performance.

[0005] Silicone-based thermoplastic vulcanizate (TPSIV) is formed by vulcanized silicone rubber particles on a thermoplastic elastomer substrate. The vulcanization process is a clean chemical reaction with no byproducts, no odor, and no volatiles. In addition, the matrix material is coated around the silicone rubber particles as a continuous phase to form a special sea-island structure, which makes it have both the excellent heat-oxidative aging resistance of silicone rubber and the excellent physical and mechanical properties and thermoplastic processing properties of thermoplastic elastomers. Compared with ordinary thermoplastic elastomers, TPSIV has excellent oil and chemical resistance.

[0006] The existing technology has the defects of insufficient temperature resistance of rubber magnets, the need for vulcanization operation, complex formula and cumbersome processing process. Therefore, how to provide a rubber magnet with simple preparation process, no need for vulcanization, halogen-free, environmentally friendly, oil-resistant and high-temperature resistant and its preparation method has become a problem that needs to be solved urgently. Summary of the invention

[0007] In order to solve the above technical problems, the present invention aims to provide a ferrite rubber magnet and its preparation method, which has a simple preparation process, does not require vulcanization, is halogen-free and environmentally friendly, is oil-resistant and high-temperature-resistant. The rubber magnet of the present invention uses a thermoplastic rubber material as an adhesive. The most prominent feature of this material is that it can show rubber elasticity at room temperature and can be plasticized and formed at high temperature, and has the characteristics of both vulcanized rubber and thermoplastic.

[0008] To achieve this object, the present invention adopts the following technical solutions:

[0009] In a first aspect, the present invention provides a rubber magnet, which includes ferrite magnetic powder, a thermoplastic rubber material and a processing aid; the thermoplastic rubber material includes a silicone-based thermoplastic vulcanized rubber.

[0010] The rubber magnet of the present invention uses silicon-based thermoplastic rubber material (TPSIV) as an adhesive. TPSIV shows rubber elasticity at room temperature and can be plasticized and formed at high temperature, and has the characteristics of both vulcanized rubber and thermoplasticity. Compared with traditional rubber processing, thermoplastic rubber material does not have the complex formula and processing process of rubber. It can be directly processed into various products using traditional plastic processing methods, such as extrusion, molding, injection molding, etc., without the need for a vulcanization process. The processing technology is simple, the molding cycle is short, and the scraps and old products can be recycled and reused. Therefore, thermoplastic rubber materials can not only meet the performance required by people, but also play a positive and effective role in saving energy, simplifying production processes, improving economic benefits, reducing labor intensity, and especially in environmental protection.

[0011] In addition, the adhesive used in the present invention adopts halogen-free environmentally friendly materials, and the magnetic properties of the prepared rubber magnet will not be reduced. After high-temperature experiments, the hardness and elongation at break change less, and it is more resistant to high-temperature aging, thereby expanding the application field of the product.

[0012] The following are preferred technical solutions of the present invention, but are not intended to limit the technical solutions provided by the present invention. Through the following preferred technical solutions, the technical objectives and beneficial effects of the present invention can be better achieved and realized.

[0013] Preferably, based on the total mass of the rubber magnet as 100wt%, the mass fraction of the ferrite powder is 85wt%-91wt%, for example, it can be 85wt%, 86wt%, 87wt%, 88wt%, 89wt%, 90wt% or 91wt%, but is not limited to the listed values, and other unlisted values ​​within the numerical range are also applicable.

[0014] The present invention further controls the mass fraction of ferrite to be 85wt%-91wt% to adjust the magnetic properties of the rubber magnet. In order to achieve the requirement of improving the performance of the magnet, the most direct method is to increase the content of magnetic powder and improve the density of the magnet. The higher the content of magnetic powder, the greater the proportion of magnetic phase, which is more conducive to obtaining higher magnetic properties. However, if the mass fraction of ferrite is too high, the content of binder is reduced accordingly, resulting in increased friction between magnetic powders, reduced orientation, and decreased magnetic properties.

[0015] Preferably, based on the total mass of the rubber magnet as 100wt%, the mass fraction of the thermoplastic rubber material is 5wt%-15wt%, for example, it can be 5wt%, 6wt%, 7wt%, 8wt%, 9wt%, 10wt%, 11wt%, 12wt%, 13wt%, 14wt% or 15wt%, but is not limited to the listed values, and other unlisted values ​​within the numerical range are also applicable.

[0016] The present invention further controls the mass fraction of the thermoplastic rubber material to be 5wt%-15wt% to adjust the mechanical properties of the rubber magnet. If the mass fraction of the thermoplastic rubber material is too high, the mechanical strength of the magnet will be reduced.

[0017] Preferably, based on the total mass of the rubber magnet as 100wt%, the mass fraction of the processing aid is 1wt%-5wt%, for example, it can be 1wt%, 2wt%, 3wt%, 4wt% or 5wt%, but is not limited to the listed values, and other unlisted values ​​within the numerical range are also applicable.

[0018] Preferably, the ferrite magnetic powder includes strontium ferrite magnetic powder and / or barium ferrite magnetic powder.

[0019] Preferably, the processing aids include plasticizers, lubricants and heat stabilizers.

[0020] Preferably, based on the total mass of the rubber magnet as 100wt%, the mass fraction of the plasticizer is 0.2wt%-0.6wt%, for example, it can be 0.2wt%, 0.25wt%, 0.3wt%, 0.35wt%, 0.4wt%, 0.45wt%, 0.5wt%, 0.55wt% or 0.6wt%, but is not limited to the listed values, and other unlisted values ​​within the numerical range are also applicable.

[0021] Preferably, based on the total mass of the rubber magnet as 100wt%, the mass fraction of the lubricant is 0.08wt%-0.2wt%, for example, it can be 0.08wt%, 0.09wt%, 0.1wt%, 0.11wt%, 0.12wt%, 0.13wt%, 0.14wt%, 0.15wt%, 0.16wt%, 0.17wt%, 0.18wt%, 0.19wt% or 0.2wt%, but is not limited to the listed values, and other unlisted values ​​within the numerical range are also applicable.

[0022] Preferably, based on the total mass of the rubber magnet as 100wt%, the mass fraction of the heat stabilizer is 0.1wt%-0.4wt%, for example, it can be 0.1wt%, 0.15wt%, 0.2wt%, 0.25wt%, 0.3wt%, 0.35wt% or 0.4wt%, but is not limited to the listed values, and other unlisted values ​​within the numerical range are also applicable.

[0023] Preferably, the plasticizer includes an environmentally friendly plasticizer (T60) and / or polypropylene adipate (PPA).

[0024] Preferably, the lubricant comprises any one of stearic acid, zinc stearate or magnesium stearate or a combination of at least two thereof, typical but non-limiting combinations comprising a combination of stearic acid and zinc stearate, a combination of zinc stearate and magnesium stearate, a combination of stearic acid and magnesium stearate, and a combination of stearic acid, zinc stearate and magnesium stearate.

[0025] Preferably, the heat stabilizer includes any one of 2,2,4-trimethyl-1,2-dihydroquinoline (RD), magnesium oxide or magnesium laurate, or a combination of at least two thereof. Typical but non-limiting combinations include a combination of RD and magnesium oxide, a combination of magnesium oxide and magnesium laurate, a combination of RD and magnesium laurate, and a combination of RD, magnesium oxide and magnesium laurate.

[0026] In a second aspect, the present invention provides a method for preparing the rubber magnet according to the first aspect, the preparation method comprising the following steps:

[0027] (1) mixing ferrite magnetic powder, thermoplastic rubber material and processing aid according to mass ratio, kneading and then crushing to obtain granular material;

[0028] (2) The granular material is formed into a rubber sheet, and the rubber sheet is laminated to obtain the rubber magnet.

[0029] The preparation process of the invention is simple, does not require vulcanization, can directly utilize traditional plastic processing methods, is easy to process, has stable product quality and size, and scraps and waste products in the production process can be recycled, saving petroleum resources and protecting the environment.

[0030] Preferably, the mixing temperature is 130°C-140°C, for example, it can be 130°C, 131°C, 132°C, 133°C, 134°C, 135°C, 136°C, 137°C, 138°C, 139°C or 140°C, but is not limited to the listed values, and other unlisted values ​​within the numerical range are also applicable.

[0031] Preferably, the kneading time is 0.5h-3h, for example, 0.5h, 1h, 1.5h, 2h, 2.5h or 3h, but is not limited to the listed values, and other values ​​not listed within the numerical range are also applicable.

[0032] Preferably, the molding comprises calendering molding or extrusion molding, preferably calendering molding.

[0033] The numerical range described in the present invention not only includes the point values ​​listed above, but also includes any point values ​​between the above numerical ranges that are not listed. Due to space limitations and for the sake of simplicity, the present invention no longer exhaustively lists the specific point values ​​included in the range.

[0034] Compared with the prior art, the present invention has at least the following beneficial effects:

[0035] (1) The rubber magnet of the present invention uses a silicon-based thermoplastic rubber material (TPSIV) as an adhesive. TPSIV exhibits rubber elasticity at room temperature and can be plasticized and formed at high temperature, and has the characteristics of both vulcanized rubber and thermoplasticity. Compared with traditional rubber processing, thermoplastic rubber materials do not have the complex formula and processing process of rubber, and both adhesives and processing aids are halogen-free and environmentally friendly materials. The magnetic properties of the prepared rubber magnet will not be reduced, and the hardness and elongation at break will change less after high-temperature testing, and it is more resistant to high-temperature aging, thereby expanding the application field of the product.

[0036] (2) TPSIV as an adhesive can be directly processed into various products using traditional plastic processing methods such as extrusion, molding, injection molding, etc., without the need for vulcanization process, simple processing technology, short molding cycle, and its scraps and old products can be recycled for reuse. Therefore, thermoplastic rubber materials can not only meet the performance required by people, but also play a positive and effective role in saving energy, simplifying production processes, improving economic benefits, reducing labor intensity, and especially in environmental protection. DETAILED DESCRIPTION

[0037] The technical solution of the present invention is further described below in conjunction with specific implementation methods. However, the following examples are only simplified examples of the present invention and do not represent or limit the scope of protection of the present invention. The scope of protection of the present invention shall be subject to the claims.

[0038] In the following examples, unless otherwise specified, all reagents and consumables were purchased from conventional reagent manufacturers in the field; unless otherwise specified, the experimental methods and technical means used were conventional methods and means in the field.

[0039] In the following embodiments, the specific grades of silicone-based thermoplastic vulcanizate (TPSIV) are Silike 2150-70A, 2150-80A, 2250-75A, 2350-65A and 3100-65A; T60 is an environmentally friendly plasticizer (Green Union Chemical Technology Co., Ltd.), PPA is a plasticizer polypropylene adipate (Tianjin Aokeyou International Wool Co., Ltd.), and RD is a thermal stabilizer 2,2,4-trimethyl-1,2-dihydroquinoline (Jiangsu Runfeng Synthetic Technology Co., Ltd.).

[0040] Example 1

[0041] This embodiment provides a rubber magnet, which includes strontium ferrite magnetic powder SrO·6Fe2O3 (Toda magnetic powder of Dongci), silicon-based thermoplastic vulcanized rubber (brand: 2150-70A), plasticizer PAA, lubricant stearic acid and heat stabilizer RD;

[0042] Taking the total mass of the rubber magnet as 100wt%, the mass fraction of the Dongci Toda magnetic powder is 90.28wt%, the mass fraction of the silicone-based thermoplastic vulcanized rubber (2150-70A) is 9wt%, the mass fraction of the plasticizer PAA is 0.45wt%, the mass fraction of the lubricant stearic acid is 0.09wt%, and the mass fraction of the heat stabilizer RD is 0.18wt%. The specific composition and raw material mass are shown in Table 1 below;

[0043] The method for preparing the rubber magnet provided in this embodiment comprises the following steps:

[0044] (1) mixing ferrite magnetic powder, thermoplastic rubber material and processing aid according to mass ratio, kneading at 130° C. for 1.5 h and then crushing to obtain granular material;

[0045] (2) The granular material is calendered to obtain a rubber sheet, and the rubber sheet is laminated multiple times to obtain a rubber magnet with a thickness of 3 mm.

[0046] Example 2

[0047] This embodiment provides a rubber magnet, which includes strontium ferrite magnetic powder (Dongci Toda magnetic powder), silicon-based thermoplastic vulcanized rubber (brand: 2250-75A), plasticizer T60, lubricant stearic acid and heat stabilizer magnesium oxide;

[0048] Taking the total mass of the rubber magnet as 100wt%, the mass fraction of the Dongci Toda magnetic powder is 90.26wt%, the mass fraction of the silicone-based thermoplastic vulcanized rubber (2250-75A) is 9.02wt%, the mass fraction of the plasticizer T60 is 0.43wt%, the mass fraction of the lubricant stearic acid is 0.11wt%, and the mass fraction of the heat stabilizer magnesium oxide is 0.18wt%. The specific composition and raw material mass are shown in Table 1 below;

[0049] The method for preparing the rubber magnet provided in this embodiment comprises the following steps:

[0050] (1) mixing ferrite magnetic powder, thermoplastic rubber material and processing aid according to mass ratio, kneading at 135° C. for 1 hour and then crushing to obtain granular material;

[0051] (2) The granular material is calendered to obtain a rubber sheet, and the rubber sheet is laminated multiple times to obtain a rubber magnet with a thickness of 3 mm.

[0052] Example 3

[0053] This embodiment provides a rubber magnet, which includes strontium ferrite magnetic powder (Dongci Toda magnetic powder), silicon-based thermoplastic vulcanized rubber (brand: 2250-75A), plasticizer T60, lubricant stearic acid and heat stabilizer RD;

[0054] Taking the total mass of the rubber magnet as 100wt%, the mass fraction of the Dongci Toda magnetic powder is 90.28wt%, the mass fraction of the silicone-based thermoplastic vulcanized rubber (2250-75A) is 9wt%, the mass fraction of the plasticizer T60 is 0.45wt%, the mass fraction of the lubricant stearic acid is 0.09wt%, and the mass fraction of the heat stabilizer RD is 0.18wt%. The specific composition and raw material mass are shown in Table 1 below;

[0055] The method for preparing the rubber magnet provided in this embodiment comprises the following steps:

[0056] (1) mixing ferrite magnetic powder, thermoplastic rubber material and processing aid according to mass ratio, kneading at 135° C. for 1.5 h and then crushing to obtain granular material;

[0057] (2) The granular material is calendered to obtain a rubber sheet, and the rubber sheet is laminated multiple times to obtain a rubber magnet with a thickness of 3 mm.

[0058] Example 4

[0059] This embodiment provides a rubber magnet, which includes strontium ferrite magnetic powder (Dongci Toda magnetic powder), silicon-based thermoplastic vulcanized rubber (brand: 3100-65A), plasticizer T60, lubricant zinc stearate and heat stabilizer RD;

[0060] Taking the total mass of the rubber magnet as 100wt%, the mass fraction of the Dongci Toda magnetic powder is 90.28wt%, the mass fraction of the silicone-based thermoplastic vulcanized rubber (3100-65A) is 9wt%, the mass fraction of the plasticizer T60 is 0.44wt%, the mass fraction of the lubricant zinc stearate is 0.1wt%, and the mass fraction of the heat stabilizer RD is 0.18wt%. The specific composition and raw material mass are shown in Table 1 below;

[0061] The method for preparing the rubber magnet provided in this embodiment comprises the following steps:

[0062] (1) mixing ferrite magnetic powder, thermoplastic rubber material and processing aid according to mass ratio, kneading at 140° C. for 0.5 h and then crushing to obtain granular material;

[0063] (2) The granular material is calendered to obtain a rubber sheet, and the rubber sheet is laminated multiple times to obtain a rubber magnet with a thickness of 3 mm.

[0064] Example 5

[0065] This embodiment provides a rubber magnet, which is different from Example 1 only in that, when preparing the rubber magnet, based on the total mass of the rubber magnet as 100wt%, the mass fraction of the Dongci Toda magnetic powder is 80.28wt%, and the reduced content is proportionally distributed to the silicone-based thermoplastic vulcanized rubber (2150-70A), plasticizer PAA, lubricant stearic acid and heat stabilizer RD.

[0066] Example 6

[0067] This embodiment provides a rubber magnet, which is different from Example 1 only in that, when preparing the rubber magnet, based on the total mass of the rubber magnet as 100wt%, the mass fraction of the Dongci Toda magnetic powder is 95.28wt%, and the excess content is proportionally reduced from the silicone-based thermoplastic vulcanized rubber (2150-70A), plasticizer PAA, lubricant stearic acid and heat stabilizer RD.

[0068] Example 7

[0069] This embodiment provides a rubber magnet, which is different from Example 1 only in that, when preparing the rubber magnet, based on the total mass of the rubber magnet as 100wt%, the mass fraction of the silicone-based thermoplastic vulcanized rubber (2150-70A) is 16.2wt%, and the excess content is proportionally reduced from the Dongci Toda magnetic powder, plasticizer PAA, lubricant stearic acid and heat stabilizer RD.

[0070] Comparative Example 1

[0071] This comparative example provides a rubber magnet, which is different from Example 1 only in that when preparing the rubber magnet, the 2150-70A silicone-based thermoplastic vulcanized rubber is replaced with an equal mass of nitrile rubber (NBR, 9003-18-3), 0.3% sulfur is added to the processing aid, and the prepared rubber magnet is vulcanized at 150°C for 45 minutes to obtain a vulcanized magnetic sheet.

[0072] Comparative Example 2

[0073] This comparative example provides a rubber magnet, which is different from Example 1 only in that when preparing the rubber magnet, the 2150-70A silicone-based thermoplastic vulcanized rubber is replaced with an equal mass of styrene (SBS, 100-42-5).

[0074] Test method: (1) The rubber magnetic sheets prepared in Examples 1 to 7 and Comparative Examples 1 to 2 were subjected to a high temperature aging test and the results are shown in Table 2;

[0075] (2) The magnetic properties of the rubber magnetic sheets prepared in Examples 1 to 7 and Comparative Examples 1 to 2 were measured and the results are shown in Table 3.

[0076] Table 1

[0077]

[0078]

[0079] Table 2

[0080]

[0081]

[0082] Table 3

[0083]

[0084] The test results show that:

[0085] (1) It can be seen from Examples 1-4 that the present invention uses thermoplastic rubber material (TPSIV) as an adhesive, and both the adhesive and the processing aid are halogen-free and environmentally friendly materials. The magnetic properties of the rubber magnet prepared will not be reduced. After high-temperature tests, the hardness and elongation at break change less, the mechanical properties are better, and it is more resistant to high-temperature aging. The preparation process does not require a vulcanization step, the processing technology is simple, and the molding cycle is short. It plays a positive and effective role in saving energy, simplifying production processes, improving economic benefits, reducing labor intensity, and especially in environmental protection.

[0086] (2) By comparing Example 1 with Examples 5-6, it can be seen that the present invention further controls the mass fraction of ferrite to 85wt%-91wt% to regulate the magnetic properties of the rubber magnet. If the mass fraction of ferrite is too high, the friction between the magnetic powders will increase and the magnetic properties will decrease.

[0087] (3) By comparing Example 1 with Example 7, it can be seen that the present invention further optimizes the mass fraction of the thermoplastic rubber material to 5wt%-15wt% to adjust the mechanical properties of the rubber magnet. If the mass fraction of the thermoplastic rubber material is too high, the mechanical strength of the magnet will be reduced; if the mass fraction of the thermoplastic rubber material is too low and the magnetic powder is too much, it cannot be molded.

[0088] (4) It can be seen from Example 1 and Comparative Examples 1-2 that the TPSIV adhesive of the present invention, which does not require vulcanization, can completely replace the conventional NBR / SBS adhesive that requires vulcanization, thereby simplifying the process manufacturing process and cost. In addition, the hardness and elongation at break change significantly less after high temperature testing, that is, the TPSIV adhesive of the present invention is more resistant to high temperature aging.

[0089] In summary, the rubber magnet of the present invention uses thermoplastic rubber material (TPSIV) as an adhesive. TPSIV shows rubber elasticity at room temperature and can be plasticized and formed at high temperature, and has the characteristics of both vulcanized rubber and thermoplasticity. Compared with traditional rubber processing, thermoplastic rubber materials do not have the complex formula and processing process of rubber, and both adhesives and processing aids are halogen-free and environmentally friendly materials. The magnetic properties of the prepared rubber magnet will not only not decrease, but also the hardness and elongation at break will change less after high temperature testing, and it is more resistant to high temperature aging, thereby expanding the application field of the product.

[0090] The applicant declares that the above is only a specific implementation mode of the present invention, but the protection scope of the present invention is not limited thereto. Those skilled in the art should understand that any changes or substitutions that can be easily thought of by those skilled in the art within the technical scope disclosed by the present invention shall fall within the protection scope and disclosure scope of the present invention.

Claims

1. A rubber magnet, characterized in that: The rubber magnet comprises ferrite magnetic powder, thermoplastic rubber material and processing aid; the thermoplastic rubber material comprises silicon-based thermoplastic vulcanized rubber.

2. The rubber magnet according to claim 1, characterized in that: Based on the total mass of the rubber magnet being 100wt%, the mass fraction of the ferrite powder is 85wt%-91wt%, the mass fraction of the thermoplastic rubber material is 5wt%-15wt%, and the mass fraction of the processing aid is 0.4wt%-5wt%.

3. The rubber magnet according to claim 1 or 2, characterized in that: The ferrite magnetic powder includes strontium ferrite magnetic powder and / or barium ferrite magnetic powder.

4. The rubber magnet according to any one of claims 1 to 3, characterized in that: The processing aids include plasticizers, lubricants and heat stabilizers.

5. The rubber magnet according to claim 4, characterized in that: Based on 100wt% of the total mass of the rubber magnet, the mass fraction of the plasticizer is 0.2wt%-0.6wt%, the mass fraction of the lubricant is 0.08wt%-0.2wt%, and the mass fraction of the heat stabilizer is 0.1wt%-0.4wt%.

6. The preparation method according to claim 4 or 5, characterized in that: The plasticizer includes an environmentally friendly plasticizer and / or polypropylene adipate; Preferably, the lubricant comprises any one or a combination of at least two of stearic acid, zinc stearate or magnesium stearate; Preferably, the heat stabilizer includes any one of 2,2,4-trimethyl-1,2-dihydroquinoline, magnesium oxide or magnesium laurate, or a combination of at least two thereof.

7. A method for preparing a rubber magnet according to any one of claims 1 to 6, characterized in that: The preparation method comprises the following steps: (1) mixing ferrite magnetic powder, thermoplastic rubber material and processing aid according to mass ratio, kneading and then crushing to obtain granular material; (2) The granular material is formed into a rubber sheet, and the rubber sheet is laminated to obtain the rubber magnet.

8. The preparation method according to claim 7, characterized in that: The temperature of the banburying is 130°C-140°C.

9. The preparation method according to claim 7 or 8, characterized in that: The mixing time is 0.5h-3h.

10. The preparation method according to any one of claims 7 to 9, characterized in that: The molding includes calendering molding or extrusion molding, preferably calendering molding.

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