Heat Dissipation Coating Composition, Its Preparation Method and Its Application in Battery Guard Plate

Abstract

The present invention relates to a heat dissipation coating composition, a preparation method thereof, and its application in battery shields, belonging to the technical field of new energy heat dissipation coatings. The present invention uses methyl methacrylate, 2-vinyl pyridine, methacrylamide, dipropylene glycol diacrylate, azobisisobutyronitrile, and tetradecane as raw materials to first prepare a coating dispersion. Then, based on an in-situ polymerization method, the coating dispersion is used to polymerize and coat hydroxylated graphene to construct a coating layer having amino groups and pyridine rings to obtain coated particles. Then, ethylene glycol diglycidyl ether containing a double-ended epoxy group is used as a bridging agent. Through the addition of amino groups and epoxy groups, amino boron nitride is compounded onto the coated particles to prepare modified composite particles. After the modified composite particles are blended with components such as a water-based epoxy resin, a heat dissipation coating composition is obtained. The heat dissipation coating composition has excellent heat dissipation performance. Even after multiple heating and cooling cycles, the coating can still maintain a good heat dissipation effect, making it suitable for application in battery shields.

Description

Technical Field

[0001] The present invention belongs to the technical field of heat dissipation coatings, and in particular relates to a heat dissipation coating composition, a preparation method thereof, and an application thereof in a battery shield. Background Art

[0002] Thermal dissipation coatings are specialized coatings used to improve the heat dissipation efficiency of surfaces and reduce system temperatures. Due to their excellent heat dissipation, corrosion resistance, and waterproofing properties, thermal dissipation coatings are widely used in batteries, construction, automotive, and other fields. Most thermal dissipation coatings are primarily composed of epoxy resins, inorganic particles, curing agents, and other ingredients. Inorganic particles, as functional ingredients, directly determine the thermal dissipation performance of thermal dissipation coatings. While many existing technologies utilize a combination of inorganic particles of different types and sizes to achieve a complementary effect, enabling thermal dissipation coatings to achieve superior heat dissipation, these existing technologies still have drawbacks that limit their practical application effectiveness. This is because the simple combination of inorganic particles does not significantly enhance the heat dissipation effect, leaving room for further improvement. Furthermore, thermal dissipation coatings (thermal coatings) inevitably experience temperature increases and decreases during application, especially when applied to battery shields. This continuous cycle can easily cause inorganic particle migration and precipitation, significantly reducing the heat dissipation effect. Summary of the Invention

[0003] In response to the problems existing in the prior art, the purpose of the present invention is to provide a heat dissipation coating composition, a preparation method thereof and its application in battery guard plates. The present invention uses methyl methacrylate, 2-vinylpyridine, methacrylamide, dipropylene glycol diacrylate, azobisisobutyronitrile and tetradecane as raw materials to first prepare a coating dispersion, and then based on an in-situ polymerization method, uses the coating dispersion to polymerize and coat hydroxylated graphene to construct a coating layer having amino and pyridine rings to obtain coated particles. Then, ethylene glycol diglycidyl ether containing a double-ended epoxy group is used as a bridging agent, and amino boron nitride is compounded to the coated particles through the addition of amino and epoxy groups, thereby preparing modified composite particles. After the modified composite particles are blended with components such as water-based epoxy resin, a heat dissipation coating composition is obtained. The heat dissipation coating composition has excellent heat dissipation performance. Even after multiple heating and cooling cycles, the coating can still maintain an excellent heat dissipation effect, and is suitable for application in battery guard plates.

[0004] The purpose of the present invention can be achieved through the following technical solutions:

[0005] A heat dissipation coating composition is prepared from 50 parts by weight of a waterborne epoxy resin, 3-4 parts by weight of modified composite particles, 10-12 parts by weight of a curing agent, and 0.2-0.3 parts by weight of a defoaming agent.

[0006] As a preferred technical solution of the present invention, the modified composite particles are prepared by the following steps:

[0007] Step A: 3-3.5 parts by weight of methyl methacrylate, 0.15 parts by weight of 2-vinylpyridine, 0.2 parts by weight of methacrylamide, 0.9-1 parts by weight of dipropylene glycol diacrylate, and 0.15 parts by weight of azobisisobutyronitrile are mixed under ultrasound in the dark at room temperature for 5-10 minutes, and then 60-70 parts by weight of tetradecane are added and centrifuged to obtain a coating dispersion;

[0008] Step B: mixing 10 parts by weight of hydroxylated graphene and 100 parts by weight of tetradecane under ultrasonic stirring at room temperature for 15-30 minutes to obtain a particle dispersion;

[0009] Step C: adding 80 parts by weight of the coating dispersion to 100 parts by weight of the particle dispersion at 75-80° C. under a nitrogen atmosphere while stirring, and continuing to stir at a constant temperature for 2-3 hours after all the addition is complete, filtering, collecting the filter residue, washing it with deionized water, and finally vacuum drying it at 30-60° C. until constant weight is obtained to obtain coated particles;

[0010] Step D: Add 8-10 parts by weight of ethanol, 4.5-5 parts by weight of coated particles, and 1 part by weight of aminoboron nitride to 100 parts by weight of deionized water, and then stir and mix under ultrasound at room temperature for 10-15 minutes. Then, add 0.7 parts by weight of ethylene glycol diglycidyl ether dropwise at 35-40°C while stirring. After all the addition is complete, continue stirring at a constant temperature for 1-2 hours, filter, take the filter residue, wash with deionized water, and finally vacuum dry at 30-60°C until constant weight. The preparation is completed.

[0011] Furthermore, the power of the ultrasound in step A is 300-400W.

[0012] Furthermore, the centrifugation in step A refers to centrifugation at a speed of 500-800 rpm for 5 minutes.

[0013] Furthermore, the power of the ultrasound in step B is 300-400W.

[0014] Furthermore, the dropping rate in step C is controlled at 1-2 s / drop.

[0015] Furthermore, the aminoboron nitride in step D is prepared by the following steps:

[0016] (1) Add 1-2 parts by weight of boron nitride to 100 parts by weight of a sodium hydroxide aqueous solution, then stir and mix at 90-95° C. for 10-14 hours, filter, take the filter residue, wash with deionized water, and finally vacuum dry at 50-80° C. until constant weight, to obtain pretreated boron nitride;

[0017] (2) Pretreated boron nitride, γ-aminopropyltrimethoxysilane and ethanol aqueous solution are mixed at a mass ratio of 1:2-3:100-110 at 60-70°C for 8-10 hours, filtered, and the filter residue is washed with deionized water, and finally vacuum dried at 50-80°C until constant weight is achieved. The preparation is completed.

[0018] Preferably, the concentration of the sodium hydroxide aqueous solution in step (1) is 3-5 mol / L.

[0019] Preferably, the mass fraction of the ethanol aqueous solution in step (2) is 95%.

[0020] Furthermore, the power of the ultrasound in step D is 300-400W.

[0021] Furthermore, the dropping rate in step D is controlled at 3-4s / drop.

[0022] As a preferred technical solution of the present invention, the curing agent is diethylenetriamine.

[0023] As a preferred technical solution of the present invention, the defoaming agent is defoaming agent BYK-028.

[0024] A method for preparing a heat dissipation coating composition, comprising the following steps:

[0025] The preparation is completed by mixing the waterborne epoxy resin, modified composite particles, curing agent and defoaming agent at 20-25° C. for 10-15 minutes.

[0026] A heat dissipation coating composition is used in a battery shield, the application comprising the following steps:

[0027] The heat dissipation coating composition is applied to the outer surface of the battery guard plate, and then cured at 40-50°C for 8-10 hours, and naturally cooled to room temperature to form a coating with a thickness of 80-100 μm.

[0028] Beneficial effects of the present invention:

[0029] (1) The present invention uses methyl methacrylate, 2-vinylpyridine, methacrylamide, dipropylene glycol diacrylate, azobisisobutyronitrile and tetradecane as raw materials to first prepare a coating dispersion, and then based on the in-situ polymerization method, uses the coating dispersion to polymerize and coat hydroxylated graphene to construct a coating layer with amino and pyridine rings to obtain coated particles. Then, ethylene glycol diglycidyl ether containing a double-ended epoxy group is used as a bridging agent, and amino boron nitride is compounded onto the coated particles through the addition of amino and epoxy groups, thereby preparing modified composite particles. After the modified composite particles are blended with components such as water-based epoxy resin, a heat dissipation coating composition is obtained, which has excellent heat dissipation performance. Even after multiple heating and cooling cycles, the coating can still maintain a good heat dissipation effect, and is suitable for use in battery protective plates.

[0030] (2) Most of the heat dissipation is basically the result of the combined action of heat conduction, radiation and convection. For this reason, the present invention uses methyl methacrylate, 2-vinylpyridine, methacrylamide, dipropylene glycol diacrylate, azobisisobutyronitrile and tetradecane as raw materials to first prepare a coating dispersion, and then based on the in-situ polymerization method, uses the coating dispersion to polymerize and coat the hydroxylated graphene to construct a coating layer with amino groups and pyridine rings to obtain coated particles. The pyridine ring is a conjugated structure containing nitrogen atoms. A certain amount of surface coating can regulate the electron-phonon coupling effect, so that the vibration energy of the hydroxylated graphene can be released faster in the form of radiation, thereby improving the radiation efficiency and promoting the heat dissipation effect. However, too many pyridine rings will have a serious shielding and steric effect, which will have a negative impact on the actual heat dissipation capacity. As for the amino groups in the coating layer, they can Under the conditions of suitable temperature (suitable temperature can effectively promote the addition of amino group, i.e. primary amine, and epoxy group, and inhibit the occurrence of side reactions), the composite of coated particles and amino boron nitride is realized through the bridging effect of ethylene glycol diglycidyl ether. The introduction of amino boron nitride can greatly improve the overall thermal conductivity, i.e. thermal conductivity. Compared with the prior art which simply compounds different inorganic particles, the modified composite particles of the present invention form a more complex morphology, which can not only better build a thermal conductive network and promote the thermal conductive effect, but also increase the contact area with the air and enhance the convection effect. In addition, the present invention specifically selects hydroxylated graphene for polymerization coating to ensure the coating effect. Graphene cannot construct a coating layer well due to its low surface activity, and graphene oxide has a large steric hindrance of the carboxyl group on its surface, resulting in a reduced degree of binding with the coating layer.

[0031] (3) The modified composite particles prepared in the present invention have residual amino groups in the coating structure and / or the surface structure of amino boron nitride that can participate in the curing of waterborne epoxy resin, thereby achieving the purpose of reducing migration. BRIEF DESCRIPTION OF THE DRAWINGS

[0032] To facilitate understanding by those skilled in the art, the present invention is further described below with reference to the accompanying drawings.

[0033] Figure 1 This is a physical picture of the heat dissipation coating composition prepared in Example 1 of the present invention after being applied to a battery guard plate.

[0034] Figure 2 This is a photo of the heat dissipation coating composition prepared in Example 2 of the present invention after being applied to a battery guard plate. DETAILED DESCRIPTION

[0035] In order to further illustrate the technical means and effects adopted by the present invention to achieve the predetermined purpose of the invention, the specific implementation methods, structures, features and effects of the present invention are described in detail below in conjunction with the accompanying drawings and preferred embodiments.

[0036] The waterborne epoxy resins in the examples and comparative examples were purchased from Guangzhou Wei Chuang High-tech Materials Technology Co., Ltd., model: waterborne epoxy resin emulsion 0947A-60W; the hydroxylated graphene was purchased from Jiangsu Xianfeng Nanomaterial Technology Co., Ltd., model: XF307; the boron nitride was purchased from Shanghai Pantian Powder Materials Co., Ltd., model: PT-BN-100nm.

[0037] Example 1

[0038] A heat dissipation coating composition is prepared from 50 parts by weight of a waterborne epoxy resin, 3 parts by weight of modified composite particles, 10 parts by weight of a curing agent, and 0.2 parts by weight of a defoaming agent.

[0039] The modified composite particles are prepared by the following steps:

[0040] Step A: 3 parts by weight of methyl methacrylate, 0.15 parts by weight of 2-vinylpyridine, 0.2 parts by weight of methacrylamide, 0.9 parts by weight of dipropylene glycol diacrylate, and 0.15 parts by weight of azobisisobutyronitrile were mixed under ultrasound at room temperature in the dark for 5 minutes, and then 60 parts by weight of tetradecane was added and centrifuged to obtain a coating dispersion;

[0041] Step B: 10 parts by weight of hydroxylated graphene and 100 parts by weight of tetradecane were mixed under ultrasonic stirring at room temperature for 15 minutes to obtain a particle dispersion;

[0042] Step C: 80 parts by weight of the coating dispersion was added dropwise to 100 parts by weight of the particle dispersion at 75° C. under a nitrogen atmosphere while stirring. After all the addition was complete, the mixture was stirred at a constant temperature for 2 hours, filtered, and the filter residue was collected and washed with deionized water. Finally, vacuum dried at 30° C. until constant weight was obtained to obtain coated particles.

[0043] Step D: Add 8 parts by weight of ethanol, 4.5 parts by weight of coated particles and 1 part by weight of aminoboron nitride to 100 parts by weight of deionized water, and then stir and mix under ultrasound at room temperature for 10 minutes. Then, add 0.7 parts by weight of ethylene glycol diglycidyl ether dropwise while stirring at 35°C. After all the addition is completed, continue stirring at a constant temperature for 1 hour, filter, take the filter residue, wash with deionized water, and finally vacuum dry at 30°C until constant weight. The preparation is completed.

[0044] The power of the ultrasound in step A is 300W.

[0045] The centrifugation in step A refers to centrifugation at a speed of 500 rpm for 5 minutes.

[0046] The power of the ultrasound in step B is 300W.

[0047] The rate of the dropwise addition in step C is controlled at 1 s / drop.

[0048] The aminoboron nitride described in step D is prepared by the following steps:

[0049] (1) Add 1 part by weight of boron nitride to 100 parts by weight of a sodium hydroxide aqueous solution, then stir and mix at 90° C. for 10 hours, filter, take the filter residue, wash with deionized water, and finally vacuum dry at 50° C. until constant weight, to obtain pretreated boron nitride;

[0050] (2) Pretreated boron nitride, γ-aminopropyltrimethoxysilane and ethanol aqueous solution were mixed at a mass ratio of 1:2:100 at 60°C for 8 h, filtered, and the filter residue was washed with deionized water. Finally, vacuum dried at 50°C until constant weight was achieved. The preparation was completed.

[0051] The concentration of the sodium hydroxide aqueous solution in step (1) is 3 mol / L.

[0052] The mass fraction of the ethanol aqueous solution in step (2) is 95%.

[0053] The power of the ultrasound in step D is 300W.

[0054] The rate of the dropwise addition in step D is controlled at 3s / drop.

[0055] The curing agent is diethylenetriamine.

[0056] The defoamer is defoamer BYK-028.

[0057] A method for preparing a heat dissipation coating composition, comprising the following steps:

[0058] The preparation is completed by mixing the waterborne epoxy resin, modified composite particles, curing agent and defoaming agent at 20° C. under stirring for 10 minutes.

[0059] A heat dissipation coating composition is used in a battery shield, the application comprising the following steps:

[0060] The heat dissipation coating composition was coated on the outer surface of the battery guard plate, and then cured at 40° C. for 8 h and naturally cooled to room temperature to form a coating with a thickness of 80 μm.

[0061] Example 2

[0062] A heat dissipation coating composition is prepared from 50 parts by weight of a waterborne epoxy resin, 4 parts by weight of modified composite particles, 12 parts by weight of a curing agent, and 0.3 parts by weight of a defoaming agent.

[0063] The modified composite particles are prepared by the following steps:

[0064] Step A: 3.5 parts by weight of methyl methacrylate, 0.15 parts by weight of 2-vinylpyridine, 0.2 parts by weight of methacrylamide, 1 part by weight of dipropylene glycol diacrylate, and 0.15 parts by weight of azobisisobutyronitrile were mixed under ultrasound at room temperature in the dark for 10 minutes, and then 70 parts by weight of tetradecane was added and centrifuged to obtain a coating dispersion;

[0065] Step B: 10 parts by weight of hydroxylated graphene and 100 parts by weight of tetradecane were mixed under ultrasonic stirring at room temperature for 30 minutes to obtain a particle dispersion;

[0066] Step C: adding 80 parts by weight of the coating dispersion to 100 parts by weight of the particle dispersion at 80° C. under a nitrogen atmosphere while stirring, and continuing to stir at a constant temperature for 3 hours after all the addition is complete. The mixture is filtered, the filter residue is collected, and washed with deionized water, and finally vacuum dried at 60° C. until constant weight is obtained to obtain coated particles;

[0067] Step D: Add 10 parts by weight of ethanol, 5 parts by weight of coated particles and 1 part by weight of aminoboron nitride to 100 parts by weight of deionized water, and then stir and mix under ultrasound at room temperature for 15 minutes. Then, add 0.7 parts by weight of ethylene glycol diglycidyl ether dropwise while stirring at 40°C. After all the addition is completed, continue stirring at a constant temperature for 2 hours, filter, take the filter residue, wash with deionized water, and finally vacuum dry at 60°C until constant weight. The preparation is completed.

[0068] The power of the ultrasound in step A is 400W.

[0069] The centrifugation in step A refers to centrifugation at a speed of 800 rpm for 5 minutes.

[0070] The power of the ultrasound in step B is 400W.

[0071] The rate of the dropwise addition in step C is controlled at 2s / drop.

[0072] The aminoboron nitride described in step D is prepared by the following steps:

[0073] (1) Add 2 parts by weight of boron nitride to 100 parts by weight of a sodium hydroxide aqueous solution, then stir and mix at 95° C. for 14 h, filter, take the filter residue, wash with deionized water, and finally vacuum dry at 80° C. until constant weight, to obtain pretreated boron nitride;

[0074] (2) Pretreated boron nitride, γ-aminopropyltrimethoxysilane and ethanol aqueous solution were mixed at a mass ratio of 1:3:110 at 70°C for 10 hours, filtered, and the filter residue was washed with deionized water. Finally, vacuum dried at 80°C until constant weight was achieved.

[0075] The concentration of the sodium hydroxide aqueous solution in step (1) is 5 mol / L.

[0076] The mass fraction of the ethanol aqueous solution in step (2) is 95%.

[0077] The power of the ultrasound in step D is 400W.

[0078] The rate of the dropwise addition in step D is controlled at 4s / drop.

[0079] The curing agent is diethylenetriamine.

[0080] The defoamer is defoamer BYK-028.

[0081] A method for preparing a heat dissipation coating composition, comprising the following steps:

[0082] The preparation is completed by mixing the waterborne epoxy resin, modified composite particles, curing agent and defoaming agent at 25° C. under stirring for 15 minutes.

[0083] A heat dissipation coating composition is used in a battery shield, the application comprising the following steps:

[0084] The heat dissipation coating composition was coated on the outer surface of the battery guard plate, and then cured at 50° C. for 10 h and naturally cooled to room temperature to form a coating with a thickness of 100 μm.

[0085] Example 3

[0086] A heat dissipation coating composition is prepared from 50 parts by weight of a waterborne epoxy resin, 3.5 parts by weight of modified composite particles, 11 parts by weight of a curing agent, and 0.25 parts by weight of a defoaming agent.

[0087] The modified composite particles are prepared by the following steps:

[0088] Step A: 3.3 parts by weight of methyl methacrylate, 0.15 parts by weight of 2-vinylpyridine, 0.2 parts by weight of methacrylamide, 0.95 parts by weight of dipropylene glycol diacrylate, and 0.15 parts by weight of azobisisobutyronitrile were mixed under ultrasound at room temperature in the dark for 8 minutes, and then 65 parts by weight of tetradecane was added and centrifuged to obtain a coating dispersion;

[0089] Step B: 10 parts by weight of hydroxylated graphene and 100 parts by weight of tetradecane were mixed under ultrasonic stirring at room temperature for 20 minutes to obtain a particle dispersion;

[0090] Step C: 80 parts by weight of the coating dispersion was added dropwise to 100 parts by weight of the particle dispersion at 77° C. under a nitrogen atmosphere while stirring. After all the addition was complete, the mixture was stirred at a constant temperature for 2.5 hours, filtered, and the filter residue was washed with deionized water. Finally, vacuum dried at 45° C. until constant weight was obtained to obtain coated particles.

[0091] Step D: Add 9 parts by weight of ethanol, 4.8 parts by weight of coated particles and 1 part by weight of aminoboron nitride to 100 parts by weight of deionized water, and then stir and mix under ultrasound at room temperature for 13 minutes. Then, add 0.7 parts by weight of ethylene glycol diglycidyl ether dropwise while stirring at 38°C. After all the addition is completed, continue stirring at a constant temperature for 1.5 hours, filter, take the filter residue, wash with deionized water, and finally vacuum dry at 40°C until constant weight. The preparation is completed.

[0092] The power of the ultrasound in step A is 400W.

[0093] The centrifugation in step A refers to centrifugation at a speed of 600 rpm for 5 minutes.

[0094] The power of the ultrasound in step B is 400W.

[0095] The rate of the dropwise addition in step C is controlled at 1.5 s / drop.

[0096] The aminoboron nitride described in step D is prepared by the following steps:

[0097] (1) Add 1.5 parts by weight of boron nitride to 100 parts by weight of a sodium hydroxide aqueous solution, then stir and mix at 93°C for 12 hours, filter, take the filter residue, wash with deionized water, and finally vacuum dry at 70°C until constant weight, to obtain pretreated boron nitride;

[0098] (2) Pretreated boron nitride, γ-aminopropyltrimethoxysilane and ethanol aqueous solution were stirred at 65°C for 9 hours in a mass ratio of 1:2.5:105, filtered, and the filter residue was washed with deionized water. Finally, vacuum dried at 70°C until constant weight was achieved.

[0099] The concentration of the sodium hydroxide aqueous solution in step (1) is 4 mol / L.

[0100] The mass fraction of the ethanol aqueous solution in step (2) is 95%.

[0101] The power of the ultrasound in step D is 300W.

[0102] The rate of the dropwise addition in step D is controlled at 3.5 s / drop.

[0103] The curing agent is diethylenetriamine.

[0104] The defoamer is defoamer BYK-028.

[0105] A method for preparing a heat dissipation coating composition, comprising the following steps:

[0106] The preparation is completed by mixing the waterborne epoxy resin, modified composite particles, curing agent and defoaming agent at 23° C. under stirring for 13 minutes.

[0107] A heat dissipation coating composition is used in a battery shield, the application comprising the following steps:

[0108] The heat dissipation coating composition was coated on the outer surface of the battery guard plate, and then cured at 45° C. for 9 hours and naturally cooled to room temperature to form a coating with a thickness of 90 μm.

[0109] Comparative Example 1

[0110] On the basis of Example 1, hydroxylated graphene was replaced with graphene oxide (purchased from Jiangsu Xianfeng Nanomaterial Technology Co., Ltd., model number XF002-1), and the rest remained unchanged.

[0111] Comparative Example 2

[0112] On the basis of Example 1, hydroxylated graphene was replaced with graphene (purchased from Jiangsu Xianfeng Nanomaterial Technology Co., Ltd., model number XF022-1), and the rest remained unchanged.

[0113] Comparative Example 3

[0114] Based on Example 1, the 2-vinylpyridine in step A was replaced by an equal weight of methyl methacrylate, and the rest remained unchanged.

[0115] Comparative Example 4

[0116] Based on Example 1, the amount of 2-vinylpyridine in Step A was changed to 0.25 parts by weight, and the rest remained unchanged.

[0117] Comparative Example 5

[0118] Based on Example 1, the methacrylamide in step A was replaced by an equal weight of methyl methacrylate, and the ethylene glycol diglycidyl ether in step D was replaced by an equal weight of deionized water, while the rest remained unchanged.

[0119] Comparative Example 6

[0120] Based on Example 1, ethylene glycol diglycidyl ether in step D was replaced with an equal weight of deionized water, and the rest remained unchanged.

[0121] Test Example 1

[0122] Heat dissipation performance test:

[0123] The heat dissipation coating compositions prepared in Example 1 and Comparative Examples 1-6 were respectively coated on the surface (single side, the square side) of an aluminum plate (all with dimensions of 100 mm × 100 mm × 5 mm), and then cured at 50° C. for 10 h. The coatings were naturally cooled to room temperature to form coatings with a thickness of 100 μm, and then test specimens were obtained.

[0124] The thermal conductivity of the coating of the test sample is measured using a thermal conductivity tester.

[0125] The above test sample was placed in an 85°C oven for heat treatment until the temperature of the test sample stabilized at 85°C (i.e., the temperature of the coating and the aluminum plate were both 85°C), then taken out and left to stand naturally at room temperature, and the temperature of the coating was recorded after 5 minutes.

[0126] Table 1. Thermal performance test results

[0127]

[0128] Test Example 2

[0129] Migration testing:

[0130] The heat dissipation coating compositions prepared in Example 1 and Comparative Examples 1-6 were respectively coated on the surface (single side, the square side) of an aluminum plate (all with dimensions of 100 mm × 100 mm × 5 mm), and then cured at 50° C. for 10 h. The coatings were naturally cooled to room temperature to form coatings with a thickness of 100 μm, and then test specimens were obtained.

[0131] The above test sample was placed in an oven at 50°C for heat treatment for 30 minutes, taken out, and naturally cooled to room temperature. The heat treatment and cooling were repeated 50 times (cooling after heat treatment was counted as one time), then washed with deionized water, and naturally dried to obtain a cyclic test sample; the thermal conductivity of the coating of the above cyclic test sample was measured using a thermal conductivity tester.

[0132] Table 2. Migration test results

[0133]

[0134] A comparison of Example 1, Comparative Examples 1-6, and Test Examples 1-2 shows that the heat dissipation coating composition prepared by the present invention has excellent heat dissipation performance. Even after multiple heating and cooling treatments, the coating can still maintain a high thermal conductivity coefficient, which indirectly indicates that the modified composite particles have low mobility and effectively ensure the heat dissipation effect.

[0135] against Figure 1 Analysis: This is a physical picture of the heat dissipation coating composition prepared in Example 1 of the present invention after being applied to the battery guard plate.

[0136] against Figure 2 Analysis: This is a physical picture of the heat dissipation coating composition prepared in Example 2 of the present invention after being applied to the battery guard plate.

[0137] The above description is merely a preferred embodiment of the present invention and does not constitute any form of limitation to the present invention. Although the present invention has been disclosed as above in terms of a preferred embodiment, it is not intended to limit the present invention. Any person skilled in the art can, without departing from the scope of the technical solution of the present invention, make some changes or modifications to equivalent embodiments using the technical contents disclosed above. However, any brief modifications, equivalent changes and modifications made to the above embodiments based on the technical essence of the present invention without departing from the content of the technical solution of the present invention are still within the scope of the technical solution of the present invention.

Claims

1. A heat dissipation coating composition, characterized in that: The heat dissipation coating composition is prepared from 50 parts by weight of a waterborne epoxy resin, 3-4 parts by weight of modified composite particles, 10-12 parts by weight of a curing agent, and 0.2-0.3 parts by weight of a defoaming agent; The modified composite particles are prepared by the following steps: Step A: 3-3.5 parts by weight of methyl methacrylate, 0.15 parts by weight of 2-vinylpyridine, 0.2 parts by weight of methacrylamide, 0.9-1 parts by weight of dipropylene glycol diacrylate, and 0.15 parts by weight of azobisisobutyronitrile are mixed under ultrasound in the dark at room temperature for 5-10 minutes, and then 60-70 parts by weight of tetradecane are added and centrifuged to obtain a coating dispersion; Step B: mixing 10 parts by weight of hydroxylated graphene and 100 parts by weight of tetradecane under ultrasonic stirring at room temperature for 15-30 minutes to obtain a particle dispersion; Step C: adding 80 parts by weight of the coating dispersion to 100 parts by weight of the particle dispersion at 75-80° C. under a nitrogen atmosphere while stirring, and continuing to stir at a constant temperature for 2-3 hours after all the addition is complete, filtering, collecting the filter residue, washing it with deionized water, and finally vacuum drying it at 30-60° C. until constant weight is obtained to obtain coated particles; Step D: Add 8-10 parts by weight of ethanol, 4.5-5 parts by weight of coated particles, and 1 part by weight of aminoboron nitride to 100 parts by weight of deionized water, and then stir and mix under ultrasound at room temperature for 10-15 minutes. Then, add 0.7 parts by weight of ethylene glycol diglycidyl ether dropwise at 35-40°C while stirring. After all the addition is complete, continue stirring at a constant temperature for 1-2 hours, filter, take the filter residue, wash with deionized water, and finally vacuum dry at 30-60°C until constant weight. The preparation is completed.

2. The heat dissipation coating composition according to claim 1, characterized in that: The rate of the dropwise addition in step C is controlled at 1-2 s / drop.

3. The heat dissipation coating composition according to claim 1, wherein: The aminoboron nitride described in step D is prepared by the following steps: (1) Add 1-2 parts by weight of boron nitride to 100 parts by weight of a sodium hydroxide aqueous solution, then stir and mix at 90-95° C. for 10-14 hours, filter, take the filter residue, wash with deionized water, and finally vacuum dry at 50-80° C. until constant weight, to obtain pretreated boron nitride; (2) Pretreated boron nitride, γ-aminopropyltrimethoxysilane and ethanol aqueous solution are mixed at a mass ratio of 1:2-3:100-110 at 60-70°C for 8-10 hours, filtered, and the filter residue is washed with deionized water, and finally vacuum dried at 50-80°C until constant weight is achieved. The preparation is completed.

4. The heat dissipation coating composition according to claim 3, wherein: The concentration of the sodium hydroxide aqueous solution in step (1) is 3-5 mol / L.

5. The heat dissipation coating composition according to claim 1, characterized in that: The rate of the dropwise addition in step D is controlled at 3-4 s / drop.

6. The heat dissipation coating composition according to claim 1, characterized in that: The curing agent is diethylenetriamine.

7. The heat dissipation coating composition according to claim 1, characterized in that: The defoamer is defoamer BYK-028.

8. A method for preparing the heat dissipation coating composition according to any one of claims 1 to 7, characterized in that: The preparation method comprises the following steps: The preparation is completed by mixing the waterborne epoxy resin, modified composite particles, curing agent and defoaming agent at 20-25° C. for 10-15 minutes.

9. Use of the heat dissipation coating composition according to any one of claims 1 to 7 in a battery shield, characterized in that: The application comprises the following steps: The heat dissipation coating composition is applied to the outer surface of the battery guard plate, and then cured at 40-50°C for 8-10 hours, and naturally cooled to room temperature to form a coating with a thickness of 80-100 μm.

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