Fish scale biomimetic modified graphite heat-conducting waterproof coating and preparation method thereof

Abstract

The application provides a preparation method of fish scale biomimetic modified graphite heat-conducting waterproof paint and relates to the technical field of heat-conducting waterproof paint, which comprises the following steps: preparing a modified scale graphite precursor, preparing a modified scale sericite and preparing the fish scale biomimetic modified graphite heat-conducting waterproof paint. The fish scale biomimetic modified graphite heat-conducting waterproof paint comprises 3-65% of modified scale graphite, 8-50% of modified scale sericite, 0-55% of calcium carbonate, 11-20% of polyether, 11-20% of chlorinated paraffin, 0.1-0.9% of a chain extender, 0.01-0.1% of a defoaming agent, 0.01-0.05% of a wetting dispersant, 0.1-0.8% of silica aerogel powder and 0.01-0.15% of a catalyst drier according to the mass percentage. The paint has high tensile strength, elongation at break and heat conductivity, a long storage stability period and excellent water impermeability.

Description

TECHNICAL FIELD

[0001] The application belongs to the technical field of heat-conducting waterproof coating, and particularly relates to a fish scale biomimetic modified graphite heat-conducting waterproof coating and a preparation method thereof. BACKGROUND

[0002] The heat-conducting waterproof coating is a material with heat conduction and waterproof functions, and is widely used in the fields of building, electronics, etc. In the national standard GB / T19250 "Polyurethane Waterproof Coating", the single-component polyurethane waterproof coating is divided into three product systems of I, II and III grades, the I-type product requires that the tensile strength is greater than or equal to 2.0 MPa, and the elongation at break is greater than or equal to 500%; the III-type product requires that the tensile strength is greater than or equal to 12 MPa, and the elongation at break is greater than or equal to 250%. The existing waterproof product film has the following defects: firstly, the I-type product has high elongation at break but low tensile strength, and the III-type product has high tensile strength but low elongation at break, and the I-type and III-type products have the problem that the tensile strength and the elongation at break cannot be compatible. Secondly, the existing waterproof coating film has low heat transfer performance, which causes a large temperature difference between the film layers, increases the internal stress of the film due to thermal expansion and contraction, promotes the film to bubble and fall off, and reduces the service life of the film. Thirdly, the existing waterproof product film has relatively high water absorption, which reduces the corrosion resistance of the waterproof coating. Fourthly, the existing waterproof product has a short storage period and is prone to filler settlement. SUMMARY

[0003] The application overcomes the defects that the tensile strength and the elongation at break cannot be compatible in the existing waterproof coating product technology, and solves the problems of low thermal conductivity, high water absorption and poor storage stability. The application provides a fish scale biomimetic modified graphite heat-conducting waterproof coating and a preparation method thereof, and the obtained product has high tensile strength, elongation at break and thermal conductivity, a long storage stability period and excellent water impermeability.

[0004] The application solves the above technical problems through the following technical scheme.

[0005] The application provides a preparation method of a fish scale biomimetic modified graphite heat-conducting waterproof coating, which comprises the following steps: S1. mixing flake graphite powder and an intercalation agent, and obtaining intercalated flake graphite through intercalation and vacuum dewatering; adding a silane coupling agent solution dropwise in the intercalated flake graphite, and obtaining modified flake graphite through modification and centrifugation; adding the modified flake graphite into polyether for grinding to obtain a modified flake graphite precursor;

[0006] S2. dispersing sericite powder in an intercalation agent solution, and obtaining intercalated sericite through intercalation, centrifugation, washing and drying; grinding the intercalated sericite, and adding a silane coupling agent solution dropwise in the grinding process to obtain modified flake sericite;

[0007] S3. Add polyether, wetting dispersant, chlorinated paraffin, silica aerogel powder, modified flaky sericite, calcium carbonate and modified flaky graphite precursor according to the proportion and mix uniformly, vacuum dewatering to obtain the coating precursor, then add chain extender for crosslinking polymerization, and then add defoaming agent and catalyst to vacuum defoam to obtain the fish scale biomimetic modified graphite heat-conducting waterproof coating.

[0008] In S1, the flaky graphite powder fineness is 325-20000 mesh; the intercalation agent is a sulfoxide compound, preferably a methyl sulfoxide compound, such as dimethyl sulfoxide.

[0009] In S1, the mass ratio of the flaky graphite powder to the intercalation agent is 1:(1.5-99), preferably 1:(1-50), for example 1:10.

[0010] In S1, the stirring speed of the intercalation is 200-400 rpm, preferably 300 rpm.

[0011] In S1, the vacuum degree of the vacuum dewatering is -0.08 to -0.09 MPa; the dewatering temperature is 120-150℃, preferably 120℃; the dewatering time is 2-6h, preferably 4h.

[0012] In S1, the standard of the vacuum dewatering is that the water content is ≤400ppm.

[0013] In S1, the temperature needs to be reduced to 55℃ after the vacuum dewatering.

[0014] In S1, the dropping and the modification need to be carried out under nitrogen protection.

[0015] In S1 and S2, the silane coupling agent is one or more of amino silane coupling agent, epoxy silane coupling agent, and mercapto silane coupling agent, preferably one or more of KH550, KH792, UP540 and UP552.

[0016] In S1 and S2, the silane coupling agent solution is a methanol solution of the silane coupling agent; the concentration of the silane coupling agent solution is 5-17wt%, preferably 10wt%.

[0017] In S1, the mass ratio of the silane coupling agent solution to the intercalated flaky graphite is 1:(90-480), preferably 1:(100-450).

[0018] In S1 and S2, the dropping speed is 0.05-0.3kg / min, preferably 0.1kg / min.

[0019] In S1, the modification adopts a colloidal mill to circulate and exfoliate.

[0020] In S1, the stirring speed during the modification is 1800-2500 rpm, preferably 2000 rpm; the modification time is 3-8 h, preferably 4 h.

[0021] In S1, the solid content after the centrifugation is 65-90%, preferably 80%.

[0022] In S1, the centrifugation is performed using a solid-liquid centrifugal separator; the purpose of the centrifugation is to separate and remove excess liquid.

[0023] In S1, the mass ratio of the modified flake graphite to the polyether is 1:(1-3), preferably 1:1.

[0024] In S1, the grinding speed is 300-2000 rpm, preferably 300-1000 rpm, for example 300 rpm or 1000 rpm.

[0025] In S1, the fineness of the modified flake graphite precursor is ≤10 μm.

[0026] In S2, the sericite powder is a wet sericite powder; the sericite powder has a fineness of 325-1250 mesh.

[0027] In S2, the intercalation agent solution is a potassium acetate aqueous solution; the concentration of the intercalation agent solution is 7-14 wt%, preferably 10 wt%.

[0028] In S2, the mass ratio of the sericite powder to the intercalation agent solution is 1:(2-5), preferably 1:4.

[0029] In S2, the stirring speed during the intercalation is 800-1500 rpm, preferably 1000 rpm; the intercalation time is 2-6 h, preferably 4 h.

[0030] In S2, the washing operation is performed by washing with deionized water 3 times.

[0031] In S2, the drying temperature is 105-125°C, preferably 120°C; the drying needs to be performed until a constant weight is reached, so the drying time needs to be adjusted according to the time required to reach a constant weight; preferably, the drying time is 0.5-5 h, for example 1 h.

[0032] In S2, the grinding is performed using a ball mill.

[0033] In S2, the mass ratio of the intercalated sericite to the silane coupling agent solution is (100-250):1, preferably (100-200):1.

[0034] In S2, the modified flake sericite has a fineness of ≤10 μm.

[0035] In S3, the stirring speed in the adding process is 150-400 rpm, preferably 300 rpm.

[0036] In S3, the temperature of the vacuum dehydration is 120℃, the time of the vacuum dehydration is 4h, and the vacuum degree of the vacuum dehydration is ≤-0.08 MPa.

[0037] In S3, the temperature needs to be reduced to 70℃ after the vacuum dehydration.

[0038] In S3, the water content of the coating precursor is ≤400 ppm.

[0039] In S3, the cross-linking polymerization needs to be carried out under nitrogen protection, the temperature of the cross-linking polymerization is 80℃, the stirring speed of the cross-linking polymerization is 300-600 rpm, and the time of the cross-linking polymerization is ≥3 hours.

[0040] In S3, the temperature needs to be reduced to 60℃ after the cross-linking polymerization, and then the defoaming agent and the drying catalyst are added.

[0041] In S3, the stirring speed of the vacuum defoaming is 100-300 rpm, the vacuum degree of the vacuum defoaming is ≤-0.08 MPa, the time of the vacuum defoaming is 5-20 min, preferably 15 min, and the temperature of the vacuum defoaming is 55-60℃, preferably 60℃.

[0042] The application also provides a fish scale biomimetic modified graphite heat-conducting waterproof coating, which comprises, by mass percentage, 3-65% modified scale graphite, 8-50% modified scale sericite, 0-55% calcium carbonate, 11-20% polyether, 11-20% chlorinated paraffin, 0.1-0.9% chain extender, 0.01-0.1% defoaming agent, 0.01-0.05% wet dispersant, 0.1-0.8% silica aerogel powder, and 0.01-0.15% drying catalyst.

[0043] Preferably, the fish scale biomimetic modified graphite heat-conducting waterproof coating comprises, by mass percentage, 5-60% modified scale graphite, 10-40% modified scale sericite, 0-40% calcium carbonate, 12-17% polyether, 12-18% chlorinated paraffin, 0.3-0.8% chain extender, 0.02-0.09% defoaming agent, 0.01-0.03% wet dispersant, 0.2-0.7% silica aerogel powder, and 0.04-0.1% drying catalyst.

[0044] For example, 10% modified flake graphite, 40% modified flake sericite, 19% calcium carbonate, 15% polyether, 15% chlorinated paraffin, 0.5% chain extender, 0.07% defoamer, 0.01% wetting dispersant, 0.35% silica aerogel powder, 0.07% drier; or, 20% modified flake graphite, 40% modified flake sericite, 9% calcium carbonate, 15% polyether, 15% chlorinated paraffin, 0.5% chain extender, 0.07% defoamer, 0.01% wetting dispersant, 0.35% silica aerogel powder, 0.07% drier.

[0045] In which, because the modified flake graphite and the modified flake sericite affect the heat conduction performance, the content of the modified flake graphite used in the paint formula is used. The content of the polyether in the paint formula is the sum of the polyether added in S1 and the polyether added in S3.

[0046] In the present application, the fineness of the calcium carbonate is 800-2000 mesh, for example 2000 mesh.

[0047] In the present application, the polyether is a polyether polyol, preferably one or more of polyether diol, polyether triol, polyether tetraol, for example JQD-220G and / or JQD-0330N.

[0048] In the present application, the chlorinated paraffin can be one of chlorinated paraffin #42, chlorinated paraffin #52 and chlorinated paraffin #70, preferably chlorinated paraffin #52.

[0049] In the present application, the chain extender is an isocyanate chain extender, preferably Wanhua isocyanate.

[0050] In the present application, the defoamer is one of silicone defoamer, non-silicon defoamer or polyether defoamer, preferably BASF EFKA.

[0051] In the present application, the wetting dispersant is a water-oil universal dispersant, for example FT201.

[0052] In the present application, the drier is a WCAT type drier.

[0053] In the present application, the heat conductivity coefficient of the fish scale biomimetic modified graphite heat-conducting waterproof coating is 10-25 W / (m.k), the water absorption is 0.04-0.1%, the tensile strength is 12.15-16.8 MPa, and the tensile elongation at break is 1000-1550%.

[0054] In the present application, the intercalation technology is used to obtain intercalated flake graphite and intercalated sericite, and then modified to obtain modified flake graphite and modified flake sericite. This modified thin layer structure material is mostly arranged in single layer after peeling, and part of it is arranged in multiple layers. There are pores between the layers to allow macromolecular structures to enter.Figure 1 The modified flake graphite has excellent heat conduction performance, reduces the temperature gradient of the coating film, reduces the internal stress of the paint film temperature, avoids the cold and hot aging of the paint film, and reduces the paint film bubbling and peeling.

[0055] The present application adopts the bionic fish scale structure, the base material in the paint is the polyurethane resin synthesized by polyether and isocyanate, and the silica aerogel has a porous network structure. The polyurethane resin can connect the silica aerogel particles in series to form a grid, and the grid structure can improve the three-dimensional extension elasticity and stability of the film layer; at the same time, the grid will adsorb the modified thin-layer structure material to form a fish scale shape, which improves the tensile strength performance of the material, see Figure 2 The modified thin-layer structure material and the silica aerogel form an effective hydrophobic layer, which reduces the water absorption of the paint film and the water permeability of the paint film.

[0056] On the basis of conforming to the common sense in the art, the above-mentioned preferred conditions can be combined at will, that is, the preferred examples of the present application are obtained.

[0057] Compared with the prior art, the present application has the following beneficial effects:

[0058] 1. The present application adopts intercalation process to obtain intercalated flake graphite and intercalated sericite, and then modifies to obtain modified flake graphite and modified flake sericite; the modified flake graphite, which contains a modified thin-layer structure, has excellent heat conduction performance, avoids the cold and hot aging of the paint film, and also reduces the paint film bubbling and peeling.

[0059] 2. The present application adopts the design idea of bionic fish scale structure. Microscopically, the polyurethane connects the silica aerogel in series to form a grid, and the grid will adsorb the modified thin-layer structure material to form a fish scale shape. Such design improves the tensile property and stability, and can also effectively hydrophobize to reduce the water permeability of the paint film.

[0060] 3. The product prepared by the present application has a heat conduction coefficient of 10-25 W / (m.k), a water absorption of 0.04-0.1%, a tensile strength of 12.15-16.8 MPa, and a breaking elongation of 1000-1550%. In the accelerated aging storage test, there is no precipitation and delamination for 30 days; therefore, the product has good heat conduction performance, water impermeability, tensile strength, elongation at break and stability. Therefore, the product has a long storage period, corrosion resistance, and will not appear paint film bubbling and peeling, so it has a longer service life. BRIEF DESCRIPTION OF DRAWINGS

[0061] Figure 1 It is an electron microscope graph of the flake graphite powder after intercalation under the scale of 10 microns.

[0062] Figure 2 It is a paint film electron microscope graph of the fish scale bionic modified graphite heat conduction waterproof paint after film formation under the scale of 100 microns. Detailed Implementation

[0063] To facilitate understanding of the present invention, the present invention will be described more fully and in detail below with reference to preferred embodiments, but the scope of protection of the present invention is not limited to the following specific embodiments.

[0064] Unless otherwise defined, all technical terms used herein have the same meaning as commonly understood by those skilled in the art. The technical terms used herein are for the purpose of describing particular embodiments only and are not intended to limit the scope of the invention.

[0065] Table 1 lists the raw material models and manufacturers used in the embodiments of the present invention, which include, but are not limited to, the following similar raw materials and manufacturers.

[0066] Table 1 Raw Material Types and Manufacturers

[0067]

[0068]

[0069] Example 1

[0070] 1. Preparation of modified flake graphite precursor:

[0071] (1) 400 kg of DMSO was added to the reactor, and stirring was started at 300 rpm. While stirring, 40 kg of 1250 mesh flake graphite powder was added, and the temperature was raised to 120℃. Under a vacuum of -0.08 MPa, the mixture was dehydrated for 4 hours to obtain intercalated flake graphite. The microstructure is shown in the figure. Figure 1 .

[0072] (2) The intercalated flake graphite was cooled to 55°C. Under a nitrogen atmosphere and with stirring, 1 kg of a 10% silane coupling agent KH550 methanol solution was slowly added dropwise at a rate of 0.1 kg / min. A colloid mill was used for circulation at a speed of 2000 rpm. The modified flake graphite solution was obtained after 4 hours of constant temperature modification.

[0073] (3) The modified flake graphite liquid was separated and deslurried using a solid-liquid centrifuge to obtain 50 kg of modified flake graphite.

[0074] (4) 50 kg of modified flake graphite was added to 50 kg of JQD-330N polyether, stirred at 300 rpm, and the material was ground using a grinder until the fineness was 10 μm. 100 kg of modified flake graphite precursor was obtained. The microstructure is shown in [reference needed]. Figure 1 .

[0075] 2. Preparation of modified flake sericite

[0076] (1) Put 1440 kg of deionized water into the kettle, start stirring, stirring speed 300 rpm, under the stirring state, add 160 kg of potassium acetate and until completely dissolved, under stirring, add 400 kg of 800 mesh sericite powder, mix and disperse evenly, dispersion speed 1000 rpm, centrifugal separation to obtain potassium acetate intercalated sericite, and wash with deionized water three times, dry at 120°C under the condition of blowing, for 1 h, to obtain intercalated sericite.

[0077] (2) Use a ball mill grinder to grind the intercalated sericite, and add 2 kg of KH550 silane coupling agent during the grinding process at a drop rate of 0.1 kg / min; grind to a fineness of ≤10 μm to obtain modified flaky sericite.

[0078] 3. Preparation of paint

[0079] Among them, because the modified flaky graphite and the modified flaky sericite affect the thermal conductivity performance. Therefore, the content of the modified flaky graphite in the following Table 2 and Table 3 formulations is more intuitive. The composition of the modified flaky graphite precursor is only more polyether than the modified flaky graphite. The polyether content in the table formula is 1. The sum of the polyether added in step (4) of the preparation of the modified flaky graphite precursor and the polyether added in step (2) of the preparation of the paint.

[0080] (1) Prepare raw materials according to the following ratio: 5% modified flaky graphite, 40% modified flaky sericite, 24% calcium carbonate, 15% polyether (including 12% JQD-220G, 3% JQD-330N), 15% chlorinated wax, 0.5% chain extender, 0.07% defoamer, 0.01% wet dispersant, 0.35% silica aerogel powder, 0.07% catalyst.

[0081] (2) Put the polyether into the kettle, start stirring, stirring speed 300 rpm, mix evenly, under the stirring state, add the wet dispersant, chlorinated wax, silica aerogel powder, modified flaky sericite, calcium carbonate and modified flaky graphite precursor. Mix and disperse evenly, heat to 120°C, -0.08 MPa vacuum dehydration for 4 hours to obtain the paint precursor.

[0082] (3) Reduce the temperature in the kettle to 70°C, slowly add the chain extender isocyanate (TDI) under the condition of stirring speed 300-600 rpm; heat to 80±5°C, crosslink and polymerize under the condition of constant temperature in nitrogen atmosphere for 3 hours.

[0083] (4) After polymerization, the material is cooled to 60℃, and EFKA defoaming agent and a drier are added to the kettle under stirring at a stirring speed of 100-300 rpm, and defoaming is performed under a vacuum condition of -0.08 MPa for 15 minutes. The fish scale biomimetic modified graphite heat-conducting waterproof coating is obtained, wherein the microstructure of the paint film after the polyether and isocyanate are synthesized into polyurethane in the coating is shown in Figure 2 .

[0084] Examples 2-5

[0085] In the preparation process of the coating in step 3. of Examples 2-5, the proportions in step (1) are different, and details are shown in Table 2. Other steps and parameters are the same as in Example 1.

[0086] Table 2: Proportions of coating raw materials in Examples 1-5 (%)

[0087]

[0088] Comparative Examples 1-7

[0089] In the preparation process of the coating in step 3. of Comparative Examples 1-7, the proportions in step (1) are different, and details are shown in Table 3. Other steps and parameters are the same as in Example 1.

[0090] Table 3: Proportions of coating raw materials in Comparative Examples 1-7 (%)

[0091]

[0092]

[0093] Comparative Example 8

[0094] Comparative Example 8 is a commercially available coating from Changsha Feilu High Polymer Material Co., Ltd., model I-B.

[0095] Effect Examples

[0096] Thermal conductivity test method: GB / T 10297-2015 Determination of thermal conductivity coefficient of non-metallic solid materials by hot-wire method;

[0097] Water impermeability (0.3 MPa, 120 min), tensile strength (≥2 MPa, type I), elongation at break (≥500%, type I), water absorption (≤5%) and other test methods: GB / T 19250-2013 Polyurethane waterproof coating;

[0098] Accelerated aging storage test (50℃) test method: GB / T 6753.3-1986 Test method for storage stability of coatings.

[0099] The effects of the products prepared in the above examples and comparative examples after testing are shown in Table 4.

[0100] Table 4 Product effects

[0101]

[0102]

[0103] From Table 2, in Examples 1-4, the proportion of fillers in the formula is kept unchanged, the proportion of modified flake graphite is increased from 5% to 29%, and in Example 5, the content of modified flake graphite in the filler of the formula is increased to 59%. As can be seen from Examples 1-5, with the increase of modified flake graphite, the thermal conductivity, tensile strength, breaking elongation and water absorption rate are increased, and the comprehensive performance is gradually enhanced. In Comparative Example 1 to Comparative Example 2, the fillers in the formula are kept unchanged, and the modified flake sericite is reduced from 64% to 5%. In Comparative Example 3, the proportion of fillers in the formula is increased to 80%, the water absorption rate is decreased, the tensile strength is increased, but the breaking elongation is decreased, which does not meet the national standard, which is mainly because the content of polyether is reduced. In Comparative Example 4, no modified flake sericite is used, the thermal conductivity is increased, but the waterproofness is decreased, which shows that the modified flake sericite has good waterproof function. In Comparative Example 5, the content of modified flake sericite is increased to 40%, the thermal conductivity is decreased, which shows that the modified sericite has good insulation. In Comparative Example 6, no modified flake graphite and modified flake sericite are contained in the formula, and the overall performance is sharply decreased, which cannot meet the national standard. In Comparative Example 7, no modified flake graphite and modified flake sericite are contained in the formula, and no silica aerogel is contained, the storage time is 7 days without precipitation, but there is precipitation after 14 days. In Comparative Example 8, the paint is commercially available, and the performance of the examples is better.

[0104] Unless otherwise specifically indicated, all materials, reagents, instruments and equipment used in the present application can be purchased on the market or can be prepared by existing methods. The above specific examples further illustrate the purpose, technical solutions and beneficial effects of the present application. It should be understood that the above description is only a specific embodiment of the present application and is not intended to limit the present application. Any modification, equivalent replacement, improvement, etc. made within the spirit and principles of the present application shall be included in the protection scope of the present application.

Claims

1. A method for preparing a fish scale biomimetic modified graphite heat-conducting waterproof coating, characterized in that, The fish scale biomimetic modified graphite heat-conducting waterproof coating comprises, by mass fraction, 3-65% modified scale graphite, 8-50% modified scale sericite, 0-55% calcium carbonate, 11-20% polyether, 11-20% chlorinated paraffin, 0.1-0.9% chain extender, 0.01-0.1% defoaming agent, 0.01-0.05% wetting dispersant, 0.1-0.8% silica aerogel powder and 0.01-0.15% catalyst drier. The preparation method of the fish scale biomimetic modified graphite heat-conducting waterproof coating comprises the following steps: S1. mixing scale graphite powder and intercalation agent, obtaining intercalated scale graphite through intercalation and vacuum dehydration; adding silane coupling agent solution dropwise in the intercalated scale graphite, obtaining modified scale graphite through modification and centrifugation; grinding the modified scale graphite in polyether to obtain modified scale graphite precursor; S2. dispersing sericite powder in intercalation agent solution, obtaining intercalated sericite through intercalation, centrifugation, washing and drying; grinding the intercalated sericite and adding silane coupling agent solution dropwise during the grinding process to obtain modified scale sericite; S3. adding polyether, wetting dispersant, chlorinated paraffin, silica aerogel powder, modified scale sericite, calcium carbonate and modified scale graphite precursor according to the proportion and mixing uniformly, obtaining coating precursor through vacuum dehydration; then adding chain extender for crosslinking polymerization, and adding defoaming agent and catalyst drier for vacuum defoaming to obtain fish scale biomimetic modified graphite heat-conducting waterproof coating.

2. The preparation method of the fish-scale biomimetic modified graphite thermally conductive and waterproof coating as described in claim 1, characterized in that, In S1, the fineness of the scale graphite powder is 325-20000 mesh; the intercalation agent is a sulfoxide compound; In S1, the mass ratio of the scale graphite powder to the intercalation agent is 1:(1.5-99); In S1 and S2, the silane coupling agent is one or more of amino silane coupling agent, epoxy silane coupling agent and mercapto silane coupling agent; In S1 and S2, the silane coupling agent solution is a methanol solution of the silane coupling agent; the concentration of the silane coupling agent solution is 5-17wt%; In S1, the mass ratio of the silane coupling agent solution to the intercalated scale graphite is 1:(90-480); In S1, the mass ratio of the modified scale graphite to the polyether is 1:(1-3); In S1, the fineness of the modified scale graphite precursor is ≤10μm.

3. The preparation method of the fish-scale biomimetic modified graphite thermally conductive and waterproof coating as described in claim 1, characterized in that, In S1, the stirring speed of the intercalation is 200-400rpm; In S1, the vacuum degree of the vacuum dehydration is -0.08--0.09MPa, the temperature is 120-150℃, and the time is 2-6h; In S1, the standard of the vacuum dehydration is that the water content is ≤400ppm; In S1, the temperature needs to be reduced to 55℃ after the vacuum dehydration; In S1, the dropwise adding and the modification need to be carried out under nitrogen protection; In S1 and S2, the speed of the dropwise adding is 0.05-0.3kg / min; In S1, the stirring speed during the modification is 1800-2500rpm; the time of the modification is 3-8h; In S1, the solid content after the centrifugation is 65-90%; In S1, the speed of the grinding is 300-2000rpm.

4. The preparation method of the fish-scale biomimetic modified graphite thermally conductive and waterproof coating as described in claim 1, characterized in that, In S2, the sericite powder is a wet sericite powder; and the sericite powder has a fineness of 325-1250 mesh. In S2, the intercalation agent solution is a potassium acetate aqueous solution; and the concentration of the intercalation agent solution is 7-14 wt%. In S2, the mass ratio of the sericite powder to the intercalation agent solution is 1:(2-5). In S2, the modified flaky sericite has a fineness of ≤10 μm.

5. The preparation method of the fish-scale biomimetic modified graphite thermally conductive and waterproof coating as described in claim 1, characterized in that, In S2, the stirring speed of the intercalation is 800-1500 rpm, and the stirring time is 2-6 h. In S2, the drying temperature is 105-125℃, and the drying time is 0.5-5 h. In S2, the mass ratio of the intercalated sericite to the silane coupling agent solution is (100-250):

1.

6. The preparation method of the fish-scale biomimetic modified graphite thermally conductive and waterproof coating as described in claim 1, characterized in that, In S3, the vacuum dehydration temperature is 120℃, the vacuum dehydration time is 4 h, and the vacuum degree is ≤-0.08 MPa. In S3, the temperature needs to be reduced to 70℃ after the vacuum dehydration. In S3, the water content of the coating precursor is ≤400 ppm. In S3, the cross-linking polymerization needs to be carried out under nitrogen protection, the cross-linking polymerization temperature is 80℃, the stirring speed is 300-600 rpm, and the cross-linking polymerization time is ≥3 h. In S3, the temperature needs to be reduced to 60℃ after the cross-linking polymerization, and then a defoaming agent and a catalyst are added. In S3, the stirring speed of the vacuum defoaming is 100-300 rpm, the vacuum degree is ≤-0.08 MPa, the vacuum defoaming time is 5-20 min, and the vacuum defoaming temperature is 55-60℃.

7. The fish scale biomimetic modified graphite heat-conducting waterproof coating prepared by the method according to claim 1, characterized in that, According to the mass percentage, it comprises 3-65% modified flaky graphite, 8-50% modified flaky sericite, 0-55% calcium carbonate, 11-20% polyether, 11-20% chlorinated paraffin, 0.1-0.9% chain extender, 0.01-0.1% defoaming agent, 0.01-0.05% wet dispersant, 0.1-0.8% silica aerogel powder, and 0.01-0.15% catalyst.

8. The fish scale biomimetic modified graphite heat-conducting waterproof paint according to claim 7, characterized in that, According to the mass percentage, it comprises 5-60% modified flaky graphite, 10-40% modified flaky sericite, 0-40% calcium carbonate, 12-17% polyether, 12-18% chlorinated paraffin, 0.3-0.8% chain extender, 0.02-0.09% defoaming agent, 0.01-0.03% wet dispersant, 0.2-0.7% silica aerogel powder, and 0.04-0.1% catalyst.

9. The fish scale biomimetic modified graphite heat-conducting waterproof paint according to claim 7, characterized in that, The polyether is a polyether polyol. And / or, the fineness of the calcium carbonate is 800-2000 mesh. And / or, the chlorinated paraffin is one of chlorinated paraffin #42, chlorinated paraffin #52, and chlorinated paraffin #70. And / or, the chain extender is an isocyanate chain extender. And / or, the defoaming agent is a silicone defoaming agent or a non-silicone defoaming agent. And / or, the wet dispersant is a water-oil universal dispersant. And / or, the catalyst is a WCAT type catalyst.

10. The fish scale biomimetic modified graphite heat-conducting waterproof paint according to claim 7, characterized in that, The defoaming agent is a polyether type defoaming agent.

11. The fish scale biomimetic modified graphite heat-conducting waterproof coating according to any one of claims 7-10, characterized in that, The fish scale biomimetic modified graphite heat-conducting waterproof coating has a heat conductivity of 10-25 W / (m·k), a water absorption of 0.04-0.1%, a tensile strength of 12.15-16.8 MPa, and a tensile elongation at break of 1000-1550%.

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