Antistatic coating, method of making and method of use

Abstract

The application discloses an antistatic coating, a preparation method and a use method, and comprises the following raw materials in mass parts: 100 parts of room temperature vulcanized liquid silicone rubber, 10-20 parts of solvent-free silicone resin, 50-80 parts of graphene / nano titanium dioxide composite material, 0.5-2 parts of short carbon fiber, 10-20 parts of process additive, 12-20 parts of curing agent, 0.5-2 parts of tackifier and 1-4 parts of catalyst. The application adopts a silicone rubber and silicone resin blending system as a resin matrix of an antistatic layer, and adopts graphene / nano titanium dioxide composite material as a light white conductive filler to cooperate with conductive carbon black to adjust color, so that the coating forms a grayish white color. Under the premise of ensuring antistatic performance, the coating can be cured at room temperature, and the comprehensive performance is obviously improved, especially the elongation and adhesion.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of electrostatic protection, in particular to an anti-static coating, a preparation method and a use method. BACKGROUND

[0002] The pyrotechnic products represented by the propellant of the power source in the solid rocket engine are sensitive to static electricity. When the static electricity accumulated by the pyrotechnic products is too high, it may cause the combustion and explosion of the propellant, resulting in disastrous consequences. In order to reduce the risk of static electricity accumulation, the outermost layer of the pyrotechnic products needs to be coated with an anti-static coating. In addition, the outermost coating also has the effect of visual camouflage, which is generally dark green or gray white.

[0003] Due to environmental changes during storage and use of the pyrotechnic products, large deformation is easily generated. As the outermost anti-static coating, it needs to have a long elongation to cope with the stress generated during the deformation process and prevent cracking and falling off.

[0004] Room temperature vulcanized silicone rubber material has excellent thermal stability, good elasticity, good molding process, and can be cured at room temperature or medium temperature, and is a kind of flexible coating material with excellent performance. The disadvantages of silicone rubber are also more prominent, such as low mechanical properties, poor adhesion, and difficult repair. These shortcomings restrict the application of silicone rubber coating technology in the outer anti-static of pyrotechnic products.

[0005] At present, the main technical means to improve the mechanical properties of silicone rubber is to add white carbon black. In order to achieve satisfactory mechanical properties, a large amount of white carbon black needs to be added, which reduces the process performance of the silicone rubber base glue. In addition, too high white carbon black filling amount also reduces the volume fraction of conductive fillers, making it difficult to form a conductive channel, resulting in that the coating cannot quickly release the accumulated static electricity.

[0006] In order to overcome the above technical difficulties, the present application is proposed. SUMMARY

[0007] The purpose of the present application is to provide an anti-static coating, a preparation method and a use method, which overcomes the problem that the coating obtained by the existing silicone rubber coating cannot quickly release the accumulated static electricity.

[0008] The present application is realized in this way:

[0009] In a first aspect, the present application provides an anti-static coating, which comprises the following raw materials by mass fraction:

[0010] 100 parts of room temperature vulcanized liquid silicone rubber;

[0011] 10-20 parts of solvent-free silicone resin;

[0012] 50-80 parts of graphene / nano titanium dioxide composite material;

[0013] Short carbon fiber 0.5-2 parts;

[0014] Process aid 10-20 parts;

[0015] Curing agent 12-20 parts;

[0016] Adhesion promoter 0.5-2 parts;

[0017] Catalyst 1-4 parts.

[0018] In an optional embodiment, the room temperature vulcanized liquid silicone rubber is 107 silicone rubber, and the viscosity is 2000-5000 mPa·s.

[0019] In an optional embodiment, the solvent-free silicone resin is liquid pure methyl silicone resin, and the R / Si value is 0.80-0.90.

[0020] In an optional embodiment, the short carbon fiber has a length of 1-3 mm.

[0021] In an optional embodiment, the process aid is hydroxyl silicone oil, and the hydroxyl content is 4%-12%.

[0022] In an optional embodiment, the curing agent is at least one of tetraethyl orthosilicate and tetramethyl orthosilicate.

[0023] In an optional embodiment, the adhesion promoter is at least one of γ-aminopropyl triethoxysilane, N-(β-aminoethyl)-γ-aminopropyl methyl dimethoxysilane and N-(β-aminoethyl)-γ-aminopropyl trimethoxysilane.

[0024] In an optional embodiment, the catalyst is dibutyl tin dilaurate.

[0025] In a second aspect, the application provides a preparation method of the anti-static coating according to any one of the preceding embodiments, comprising: mixing room temperature vulcanized liquid silicone rubber, silicone resin, graphene / nano titanium dioxide composite material, carbon fiber and process aid in proportion to obtain a mixture A; adding a catalyst to the mixture A to obtain a mixture B; adding a mixture of a curing agent and an adhesion promoter to the mixture B to obtain the anti-static coating.

[0026] Preferably, the catalyst is added to the mixture A after the mixture A is ground to a fineness of no more than 50 μm by a three-roll grinder.

[0027] In a third aspect, the application provides a use method of the anti-static coating according to any one of the preceding embodiments, comprising: spraying or brushing the anti-static coating to the surface of a target product, and then curing at 15-40 °C for 22-26 h.

[0028] Preferably, the target product is a pyrotechnic device;

[0029] Preferably, the anti-static coating is sprayed or brushed onto the surface of the silicone rubber heat-resistant coating of the target product;

[0030] Preferably, the anti-static coating is diluted with 120# solvent gasoline before being sprayed onto the surface of the target product.

[0031] The present application has the following advantages:

[0032] The present application uses a silicone rubber and silicone resin blended system as the resin matrix of the anti-static layer, and uses graphene / nano-titanium dioxide composite material as the light white conductive filler in combination with conductive carbon black to adjust the color, so that the coating forms a grayish white color. Under the premise of ensuring the anti-static performance, it can be cured at room temperature, and the comprehensive performance is significantly improved, especially the elongation and adhesion. DETAILED DESCRIPTION

[0033] To make the purpose, technical solutions and advantages of the embodiments of the present application clearer, the technical solutions in the embodiments of the present application will be described clearly and completely below. If the specific conditions are not specified in the embodiments, they are carried out according to the conventional conditions or the conditions recommended by the manufacturer. If the reagents or instruments used are not specified by the manufacturer, they are all conventional products that can be purchased on the market.

[0034] One embodiment of the present application provides an anti-static coating, which comprises the following raw materials by mass:

[0035] Room temperature vulcanizing liquid silicone rubber 100 parts;

[0036] Solvent-free silicone resin 10-20 parts;

[0037] Graphene / nano-titanium dioxide composite material 50-80 parts;

[0038] Short carbon fiber 0.5-2 parts;

[0039] Process aid 10-20 parts;

[0040] Curing agent 12-20 parts;

[0041] Tackifier 0.5-2 parts;

[0042] Catalyst 1-4 parts.

[0043] In the present application, liquid silicone resin components are introduced into the silicone rubber curing system. The silicone resin participates in the construction of the entire silicone rubber network, improves the intermolecular force of the silicone rubber, and realizes the reinforcement of the silicone rubber. In addition, the silicone resin molecules participating in the network construction limit the flipping of the flexible segments of the silicone rubber, improve the surface energy of the silicone rubber, and significantly improve the adhesion and repairability of the silicone rubber coating.

[0044] The graphene / nano-titanium dioxide composite material forms a conductive channel as a conductive filler, and when reaching a threshold value, it gives the coating an antistatic functional characteristic. Preferably, the preparation method of the graphene / nano-titanium dioxide composite material comprises the following steps: (1) weighing nano-titanium dioxide and a polar solvent, and dispersing the weighed nano-titanium dioxide in the polar solvent under stirring to prepare a nano-titanium dioxide suspension; (2) dispersing graphene oxide in water to prepare a graphene precursor solution; (3) under stirring, dropping the graphene precursor solution into the nano-titanium dioxide suspension to prepare a graphene / nano-titanium dioxide composite dispersion; (4) continuing to stir for a period of time and then stopping, naturally standing, separating, and obtaining a lower sediment, and drying the sediment to obtain a graphene / nano-titanium dioxide composite; and (5) reducing the graphene / nano-titanium dioxide composite under an inert atmosphere for a period of time, and then naturally cooling to room temperature to obtain a graphene / nano-titanium dioxide composite material. The graphene / nano-titanium dioxide composite material is grayish white, and can be applied in a coating to obtain a grayish white coating.

[0045] The carbon fiber in the antistatic coating has an anti-settling effect, can maintain the stability of the coating, and can form a conductive channel together with the graphene / nano-titanium dioxide composite material. And by using the graphene / nano-titanium dioxide composite material and the carbon fiber together, a grayish white for camouflage can be realized.

[0046] In an optional embodiment, the room temperature vulcanized liquid silicone rubber is a 107 silicone rubber, and the viscosity is 2000 mPa·s-5000 mPa·s.

[0047] The α,ω-dihydroxyl polysiloxane is a basic glue of two-component and one-component condensation type silicone rubber, and is commonly referred to as 107 silicone rubber in the market. In the embodiment, the 107 silicone rubber with a viscosity of 2000 mPa·s-5000 mPa·s is selected, on the one hand, it is beneficial to maintain that the coating has a relatively high strength, and on the other hand, the viscosity is limited in this range, which can make the particle components better dispersed, while avoiding settling. If the viscosity is too large, the particle components cannot be uniformly dispersed; if the viscosity is too small, the particle components are easy to settle, which is not conducive to maintaining the stability of the coating.

[0048] In an optional embodiment, the solvent-free silicone resin is a liquid pure methyl silicone resin, and the R / Si value is 0.80-0.90.

[0049] The liquid pure methyl silicone resin has a very high SiO2 content, and is an excellent adhesive. It has good mutual solubility with the room temperature vulcanized liquid silicone rubber, and does not need to add a solvent. In addition, the R / Si value will affect the curing temperature and the strength and other properties of the corresponding coating.

[0050] In an optional embodiment, the length of the chopped carbon fiber is 1-3 mm. If the length of the chopped carbon fiber is too long, it is difficult to uniformly disperse in the coating, and if the length of the chopped carbon fiber is too long, the carbon fiber will cause the equipment to be blocked if the coating is sprayed. If the length of the chopped carbon fiber is too short, the carbon fiber cannot prevent the coating from settling.

[0051] In an optional embodiment, the process aid is a hydroxyl silicone oil, and the content of the hydroxyl group is 4-12%.

[0052] Generally, the curing temperature of the solvent-free silicone resin is 120°C, and the curing temperature of the room temperature vulcanized liquid silicone rubber is quite different from that of the solvent-free silicone resin. Therefore, the solvent-free silicone resin and the room temperature vulcanized liquid silicone rubber are difficult to be cured at the same temperature. In the present embodiment, the hydroxyl silicone oil is introduced, and the content of the hydroxyl group is limited. The purpose is to improve the activity of the solvent-free silicone resin, so that the solvent-free silicone resin can be cured at the same temperature range as the room temperature vulcanized liquid silicone rubber, which is beneficial to reduce the curing temperature of the coating and achieve room temperature curing.

[0053] In an optional embodiment, the curing agent is at least one of tetraethyl orthosilicate and tetramethyl orthosilicate.

[0054] In an optional embodiment, the adhesion promoter is at least one of γ-aminopropyl triethoxysilane, N-(β-aminoethyl)-γ-aminopropyl methyldimethoxysilane, and N-(β-aminoethyl)-γ-aminopropyl trimethoxysilane.

[0055] In an optional embodiment, the catalyst is dibutyltin dilaurate.

[0056] Another embodiment of the present application provides a preparation method of the anti-static coating of any one of the foregoing embodiments, comprising: mixing room temperature vulcanized liquid silicone rubber, silicone resin, graphene / nano titanium dioxide composite material, carbon fiber, and process aid in a proportion to obtain a mixture A; adding a catalyst to the mixture A to obtain a mixture B; adding a mixture of a curing agent and an adhesion promoter to the mixture B to obtain the anti-static coating.

[0057] Preferably, the catalyst is added to the mixture A, and the mixture A is ground to a fineness of not more than 50 μm by a three-roll grinder, so that the components in the mixture A can be relatively uniformly dispersed.

[0058] Another embodiment of the present application provides a use method of the anti-static coating of any one of the foregoing embodiments, comprising: spraying or brushing the anti-static coating to the surface of a target product, and then curing at 15-40°C for 22-26 h.

[0059] Preferably, the target product is a pyrotechnic product.

[0060] Preferably, the anti-static coating is sprayed or brushed onto the surface of the silicone rubber heat-resistant coating of the target product.

[0061] Preferably, before the anti-static coating is sprayed onto the surface of the target product, the coating is diluted to a suitable viscosity using 120# solvent gasoline, which facilitates uniform spraying of the coating on the surface of the target product.

[0062] The features and performance of the present application are further described in detail below in conjunction with examples.

[0063] Example 1

[0064] This example provides an anti-static coating, the raw material composition by mass as follows: 107 silicone rubber (5000 mPa·s), 100.0 parts; solvent-free silicone resin (R / Si value of 0.85), 10.0 parts; graphene / nano-titanium dioxide composite material, 50.0 parts; carbon fiber, 0.5 parts; hydroxyl silicone oil 15.0 parts; tetraethyl orthosilicate 12.0 parts; γ-aminopropyl triethoxysilane 1.0 parts; dibutyl tin dilaurate 1.0 parts.

[0065] Preparation method of the anti-static coating

[0066] The room temperature vulcanizing liquid silicone rubber, silicone resin, graphene / nano-titanium dioxide composite material, carbon fiber and process additives are mixed in a proportion to obtain a mixture A; the mixture A is ground to a fineness of not more than 50 μm by a three-roll grinder, and then a catalyst is added to the mixture A to obtain a mixture B; a mixture of a curing agent and an adhesion promoter is added to the mixture B to obtain the anti-static coating.

[0067] Use method of the anti-static coating

[0068] The outer wall of the pyrotechnic product is brushed with the anti-static coating at room temperature to form a coating, and after the coating thickness reaches 100-200 μm to meet the requirements, the coating is cured at 25 °C for 24 h.

[0069] Coating performance test

[0070] The anti-static coating test piece is prepared according to Q / G 197 “Method for Determining Tensile Strength and Elongation at Break of Heat Insulation Layer and Lining Layer Material of Solid Rocket Engine Combustion Chamber”, and the mechanical properties of the test piece are tested. The test results show that the tensile strength of the heat-resistant coating is 3.0 MPa, and the elongation at break is 70%.

[0071] The volume resistivity test piece is prepared according to GB 1410 “Volume Resistivity and Surface Resistivity of Solid Insulating Material”, and the volume resistivity of the test piece is tested. The test results show that the volume resistivity of the anti-static coating is 6×10 6 Ω·cm.

[0072] The cross-cut test is carried out in accordance with GB / T 9286 "Cross-cut test for paints and varnishes", and the grade is 0.

[0073] Steel / coating joint bond repair specimens were prepared according to QJ 2038.1, "Test Method for Interfacial Adhesion Strength of Solid Rocket Motor Combustion Chambers - Pull-Off Method," and the repair bond strength was tested. The test results showed that the volume resistivity of the antistatic coating was 2.8 MPa.

[0074] Example 2

[0075] This embodiment provides an antistatic coating, the raw material composition of which is as follows by mass: 30 parts of 107 silicone rubber (2000 mPa·s), 70 parts of 107 silicone rubber (5000 mPa·s); 20.0 parts of solvent-free silicone resin (R / Si value is 0.80); 80.0 parts of graphene / nano-titanium dioxide composite material; 2.0 parts of carbon fiber; 20.0 parts of hydroxy silicone oil; 12 parts of ethyl orthosilicate; 8 parts of methyl orthosilicate; 1.0 part of γ-aminopropyltriethoxysilane; 1.0 part of N-(β-aminoethyl)-γ-aminopropyltrimethoxysilane; and 4.0 parts of dibutyltin dilaurate.

[0076] Preparation and use of antistatic coating: same as Example 1.

[0077] Coating performance test

[0078] Antistatic coating specimens were prepared according to Q / G 197, "Determination of Tensile Strength and Elongation at Break of Insulation and Lining Materials for Solid Rocket Motor Combustion Chambers," and their mechanical properties were tested. The test results showed that the coating had a tensile strength of 5.6 MPa and an elongation at break of 52.0%.

[0079] According to GB 1410 Volume Resistivity and Surface Resistivity of Solid Insulating Materials, a volume resistivity specimen was prepared and the volume resistance of the specimen was tested. The test results showed that the volume resistance of the antistatic coating was 8×10 6 Ω·cm.

[0080] The cross-cut test is carried out in accordance with GB / T 9286 "Cross-cut test for paints and varnishes", and the grade is 0.

[0081] Steel / coating joint bond repair specimens were prepared according to QJ 2038.1, "Test Method for Interfacial Adhesion Strength of Solid Rocket Motor Combustion Chambers - Pull-Off Method," and the bond strength of the repair was tested. The test results showed that the volume resistivity of the antistatic coating was 4.8 MPa.

[0082] Example 3

[0083] The present embodiment provides an anti-static coating, the raw material composition is as follows by mass: 107 silicone rubber (5000 mPa·s), 100.0 parts; solvent-free silicone resin (R / Si value is 0.90), 15.0 parts; graphene / nano titanium dioxide composite material, 60.0 parts; carbon fiber, 1.5 parts; hydroxyl silicone oil 15 parts; methyl silicate 15 parts; γ-aminopropyl triethoxysilane 1.0 part; N-(β-aminoethyl)-γ-aminopropyl methyl dimethoxysilane 0.5 part; dibutyl tin dilaurate 3.0 parts.

[0084] Preparation and use method of the anti-static coating: same as example 1.

[0085] Coating performance test

[0086] Prepare the anti-static coating test piece according to Q / G 197 “Solid rocket engine combustion chamber heat insulation layer, liner material tensile strength, elongation at break determination method”, and test the mechanical properties of the test piece. The test results show that the tensile strength of the heat-resistant coating is 7.1 MPa, and the elongation at break is 91.0%.

[0087] Prepare the volume resistivity test piece according to GB 1410 “Solid insulating material volume resistivity and surface resistivity”, and test the volume resistivity of the test piece. The test results show that the volume resistivity of the anti-static coating is 5×10 6 Ω·cm.

[0088] Carry out grid detection according to GB / T 9286 “Color paint and varnish grid test”, and the grade is 0 level.

[0089] Prepare the joint adhesive repair test piece of steel / coating according to QJ 2038.1 “Solid rocket engine combustion chamber interface bonding strength test method”, and test the repair adhesive strength of the test piece. The test results show that the volume resistivity of the anti-static coating is 6.7 MPa.

[0090] Example 4

[0091] The present embodiment provides an anti-static coating, the raw material composition is as follows by mass: 107 silicone rubber (2000 mPa·s), 40 parts, 107 silicone rubber (5000 mPa·s), 60 parts; solvent-free silicone resin (R / Si value is 0.85) 12.0 parts; graphene / nano titanium dioxide composite material, 70.0 parts; carbon fiber, 1.5 parts; hydroxyl silicone oil 10 parts; ethyl silicate 15 parts; γ-aminopropyl triethoxysilane 0.5 parts; N-(β-aminoethyl)-γ-aminopropyl methyl dimethoxysilane 0.5 parts; N-(β-aminoethyl)-γ-aminopropyl trimethoxysilane 0.5 parts; dibutyl tin dilaurate 2.0 parts.

[0092] Preparation and use method of the anti-static coating: same as example 1.

[0093] Coating performance test

[0094] The anti-static coating test piece was prepared according to Q / G 197 "Solid Rocket Engine Combustion Chamber Insulation Layer, Lining Material Tensile Strength, Elongation at Break Determination Method", and the mechanical properties of the test piece were tested. The test results show that the tensile strength of the heat-resistant coating is 6.5 MPa, and the elongation at break is 52.0%.

[0095] The volume resistivity test piece was prepared according to GB 1410 "Volume Resistivity and Surface Resistivity of Solid Insulating Materials", and the volume resistance of the test piece was tested. The test results show that the volume resistance of the anti-static coating is 8 x 10 5 Ω·cm.

[0096] The grid test was carried out according to GB / T 9286 "Color Paint and Varnish Grid Test", and the grade was 0.

[0097] The steel / coating combined adhesive repair test piece was prepared according to QJ 2038.1 "Solid Rocket Engine Combustion Chamber Interface Adhesion Strength Test Method Tearing Method", and the repair adhesion strength of the test piece was tested. The test results show that the volume resistance of the anti-static coating is 6.7 MPa.

[0098] Comparative Example 1

[0099] This comparative example provides an anti-static coating, which is different from Example 1 only in that the raw materials are different: the solvent-free silicone resin (R / Si value is 0.85) in the raw materials is replaced by a solvent-free silicone resin (R / Si value is 0.95).

[0100] Coating performance test

[0101] The anti-static coating test piece was prepared according to Q / G 197 "Solid Rocket Engine Combustion Chamber Insulation Layer, Lining Material Tensile Strength, Elongation at Break Determination Method", and the mechanical properties of the test piece were tested. The test results show that the tensile strength of the heat-resistant coating is 6.5 MPa, and the elongation at break is 52.0%.

[0102] The volume resistivity test piece was prepared according to GB 1410 "Volume Resistivity and Surface Resistivity of Solid Insulating Materials", and the volume resistance of the test piece was tested. The test results show that the volume resistance of the anti-static coating is 8 x 10 6 Ω·cm.

[0103] The grid test was carried out according to GB / T 9286 "Color Paint and Varnish Grid Test", and the grade was 0.

[0104] The steel / coating joint adhesive repair test piece was prepared according to QJ 2038.1 "Solid Rocket Engine Combustion Chamber Interface Bonding Strength Test Method Tearing Method", and the repair adhesive strength of the test piece was tested. The test results show that the volume resistance of the anti-static coating is 2.2 MPa.

[0105] Comparative Example 2

[0106] This comparative example provides an anti-static coating, which is different from Example 1 only in that the raw material is different: the solvent-free silicone resin (R / Si value is 0.85) in the raw material is replaced by solvent-free silicone resin (R / Si value is 0.78).

[0107] Coating performance test

[0108] The anti-static coating test piece was prepared according to Q / G 197 "Solid Rocket Engine Combustion Chamber Insulation Layer, Lining Material Tensile Strength, Elongation at Break Determination Method", and the mechanical properties of the test piece were tested. The test results show that the tensile strength of the heat-resistant coating is 1.6 MPa, and the elongation at break is 102%.

[0109] The volume resistivity test piece was prepared according to GB 1410 "Volume Resistivity and Surface Resistivity of Solid Insulating Materials", and the volume resistance of the test piece was tested. The test results show that the volume resistance of the anti-static coating is 9×10 10 Ω·cm.

[0110] The grid test was carried out according to GB / T 9286 "Color Paint and Varnish Crosshatch Test", and the grade was 0 level.

[0111] The steel / coating joint adhesive repair test piece was prepared according to QJ 2038.1 "Solid Rocket Engine Combustion Chamber Interface Bonding Strength Test Method Tearing Method", and the repair adhesive strength of the test piece was tested. The test results show that the volume resistance of the anti-static coating is 1.3 MPa.

[0112] Comparative Example 3

[0113] This comparative example provides an anti-static coating, which is different from Example 1 only in that the raw material is different: the 107 silicone rubber (5000 mPa·s) in the raw material is replaced by 107 silicone rubber (5500 mPa·s).

[0114] The sample cannot be prepared.

[0115] Comparative Example 4

[0116] This comparative example provides an anti-static coating, which is different from Example 1 only in that the raw material is different: the 107 silicone rubber (5000 mPa·s) in the raw material is replaced by 107 silicone rubber (1500 mPa·s).

[0117] The anti-static coating test piece is prepared according to Q / G 197 "Solid Rocket Engine Combustion Chamber Insulation Layer, Lining Material Tensile Strength, Elongation at Break Determination Method", and the mechanical properties of the test piece are tested. The test results show that the tensile strength of the heat-resistant coating is 3.5 MPa, and the elongation at break is 50%.

[0118] The volume resistivity test piece is prepared according to GB 1410 "Volume Resistivity and Surface Resistivity of Solid Insulating Materials", and the volume resistance of the test piece is tested. The test results show that the volume resistance of the anti-static coating is 7 x 10 10 Ω·cm.

[0119] The grid test is carried out according to GB / T 9286 "Color Paint and Varnish Grid Test", and the grade is 0.

[0120] The steel / coating combined adhesive repair test piece is prepared according to QJ 2038.1 "Solid Rocket Engine Combustion Chamber Interface Adhesion Strength Test Method Tearing Method", and the repair adhesion strength of the test piece is tested. The test results show that the volume resistance of the anti-static coating is 3.6 MPa.

[0121] Comparative Example 5

[0122] This comparative example provides an anti-static coating, which is different from Example 1 only in that the raw materials are different: the hydroxyl silicone oil (15 parts) in the raw materials is replaced by 107 silicone rubber (8 parts).

[0123] The anti-static coating test piece is prepared according to Q / G 197 "Solid Rocket Engine Combustion Chamber Insulation Layer, Lining Material Tensile Strength, Elongation at Break Determination Method", and the mechanical properties of the test piece are tested. The test results show that the tensile strength of the heat-resistant coating is 4.0 MPa, and the elongation at break is 15%.

[0124] The volume resistivity test piece is prepared according to GB 1410 "Volume Resistivity and Surface Resistivity of Solid Insulating Materials", and the volume resistance of the test piece is tested. The test results show that the volume resistance of the anti-static coating is 5 x 10 6 Ω·cm.

[0125] The grid test is carried out according to GB / T 9286 "Color Paint and Varnish Grid Test", and the grade is 0.

[0126] The steel / coating combined adhesive repair test piece is prepared according to QJ 2038.1 "Solid Rocket Engine Combustion Chamber Interface Adhesion Strength Test Method Tearing Method", and the repair adhesion strength of the test piece is tested. The test results show that the volume resistance of the anti-static coating is 3.2 MPa.

[0127] Comparative Example 6

[0128] The comparative example provides an antistatic coating, which is different from example 1 only in that the raw materials are different: the hydroxyl silicone oil (15 parts) in the raw materials is replaced by 107 silicone rubber (22 parts).

[0129] The antistatic coating test piece is prepared according to Q / G 197 "Solid Rocket Engine Combustion Chamber Heat Insulation Layer and Lining Material Tensile Strength and Elongation at Break Determination Method", and the mechanical properties of the test piece are tested. The test results show that the tensile strength of the heat-resistant coating is 2.0 MPa, and the elongation at break is 170%.

[0130] The volume resistivity test piece is prepared according to GB 1410 "Volume Resistivity and Surface Resistivity of Solid Insulating Materials", and the volume resistivity of the test piece is tested. The test results show that the volume resistivity of the antistatic coating is 8×10 12 Ω·cm.

[0131] The grid test is carried out according to GB / T 9286 "Color Paint and Varnish Crosshatch Test", and the grade is 0.

[0132] The steel piece / coating combined adhesive repair test piece is prepared according to QJ 2038.1 "Solid Rocket Engine Combustion Chamber Interface Adhesion Strength Test Method Tearing Method", and the repair adhesive strength of the test piece is tested. The test results show that the volume resistivity of the antistatic coating is 3.1 MPa.

[0133] The above only describes the preferred embodiments of the present application and is not used to limit the present application. For those skilled in the art, the present application can have various modifications and changes. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present application shall be included in the protection scope of the present application.

Claims

1. An antistatic coating, characterized in that: It is composed of the following raw materials in parts by mass: 100 parts of room temperature vulcanized liquid silicone rubber; 10-20 parts of solvent-free silicone resin; 50-80 parts of graphene / nano-titanium dioxide composite material; 0.5~2 parts of chopped carbon fiber; 10~20 parts of process additives; 12-20 parts of curing agent; 0.5~2 parts of tackifier; 1-4 parts of catalyst; Among them, the room temperature vulcanized liquid silicone rubber is 107 silicone rubber with a viscosity of 2000mPa·s~5000mPa·s; the solvent-free silicone resin is liquid pure methyl silicone resin with an R / Si value of 0.80~0.90; and the process additive is hydroxyl silicone oil with a hydroxyl content of 4%~12%.

2. The antistatic coating according to claim 1, characterized in that: The length of the chopped carbon fibers is 1 to 3 mm.

3. The antistatic coating according to claim 1, characterized in that The curing agent is at least one of ethyl orthosilicate and methyl orthosilicate.

4. The antistatic coating according to claim 1, characterized in that The adhesion promoter is at least one of γ-aminopropyltriethoxysilane, N-(β-aminoethyl)-γ-aminopropylmethyldimethoxysilane and N-(β-aminoethyl)-γ-aminopropyltrimethoxysilane.

5. The antistatic coating according to claim 1, characterized in that: The catalyst is dibutyltin dilaurate.

6. A method for preparing the antistatic coating according to any one of claims 1 to 5, characterized in that: include: Mixing room temperature vulcanized liquid silicone rubber, solvent-free silicone resin, graphene / nano-titanium dioxide composite material, chopped carbon fiber and process additives in proportion to obtain a mixture A; A catalyst is added to the mixture A to obtain a mixture B; and a mixture of a curing agent and a tackifier is added to the mixture B to obtain the antistatic coating.

7. The method for preparing the antistatic coating according to any one of claim 6, wherein: Before the catalyst is added to the mixture A, the mixture A is first ground by a three-roll mill to a fineness not exceeding 50 μm.

8. A method for using the antistatic coating according to any one of claims 1 to 5, characterized in that: include: The antistatic coating is sprayed or brushed onto the surface of the target product, and then cured at 15-40° C. for 22-26 hours.

9. The method for using the antistatic coating according to claim 8, characterized in that: The target product is an explosive device.

10. The method for using the antistatic coating according to claim 8, characterized in that: The antistatic coating is sprayed or brushed onto the surface of the silicone rubber heat-resistant coating of the target product.

11. The method for using the antistatic coating according to claim 8, characterized in that: Before the antistatic coating is sprayed onto the surface of the target product, it is first diluted with 120# solvent gasoline.