High-thermal-conductivity anticorrosive paint

Abstract

The invention discloses a high-thermal-conductivity anticorrosive coating, belongs to the field of materials, and aims to solve the problem that existing anticorrosive coatings are poor in thermal conductivity and provide composition, manufacturing steps and a using method of the high-thermal-conductivity anticorrosive coating. The prepared coating is heated at low temperature after being cured at room temperature, the low-melting-point alloy plating layer on the surface is melted, and the contact points of the heat-conducting filler are mutually fused, so that the interface thermal resistance is eliminated, the heat-conducting property of the coating is qualitatively improved, and the high-heat-conductivity anticorrosive paint can be used for corrosion prevention of equipment with high heat exchange requirements.

Description

Technical Field

[0001] The present invention belongs to the field of materials, and specifically relates to a high thermal conductivity anti-corrosion coating. Background Art

[0002] In the field of anti-corrosion, there are some special devices that require high heat exchange capacity while undergoing anti-corrosion treatment, that is, the anti-corrosion coating used is required to have a high thermal conductivity coefficient. Due to the poor thermal conductivity of the basic component of the conventional anti-corrosion coating, namely organic synthetic resin, the general thermal conductivity coefficient is about 0.2 W / m·K. By filling a large amount of thermal conductive fillers, the thermal conductivity of the anti-corrosion coating can be improved. However, since the thermal conductive fillers are in a dispersed state in the coating, the contact area between them is small, and the interfacial thermal resistance is large. The thermal conductivity coefficient of the prepared anti-corrosion coating does not exceed 2 W / m·K, which cannot meet the requirements for equipment with high thermal conductivity requirements, restricting the application of anti-corrosion coatings in the field of high thermal conductivity anti-corrosion. Summary of the Invention

[0003] Aiming at the deficiencies of the prior art, the present invention provides a high thermal conductivity anti-corrosion coating. The thermal conductivity coefficient of the high thermal conductivity anti-corrosion coating after curing is above 10 W / m·K, and it can be used for the anti-corrosion of equipment with high heat exchange requirements. A low melting point alloy coating is covered on the surface of the main thermal conductive filler of the high thermal conductivity anti-corrosion coating. After the prepared coating is cured at room temperature and then heated at a low temperature, the low melting point alloy coating on the surface melts, and the contact points of the thermal conductive fillers fuse with each other, eliminating the interfacial thermal resistance and qualitatively improving the thermal conductivity performance of the coating.

[0004] To achieve the above object, the present invention adopts the following technical solutions: A high thermal conductivity anti-corrosion coating, characterized in that: the coating is composed of two components A and B. Component A is composed of the following components in mass percentage: spherical zinc powder: 70%-74%, bismuth-lead-tin-indium alloy particles: 8%-10%, liquid epoxy resin composition: 17.2%-19.2%, fumed silica: 0.8%; Component B is a modified liquid aromatic amine, and the mass ratio of the use of components A and B is 18:1.

[0005] Among them, the median particle size of the spherical zinc powder in component A is 20±2 μm. The spherical zinc powder is the main thermal conductive filler. By filling a large amount of spherical zinc powder, the spherical zinc powders will contact each other to form a thermal conduction channel, and phonons propagate in the thermal conduction channel.

[0006] Among them, the bismuth-lead-tin-indium alloy particles in component A have a melting point of 57°C. The bismuth-lead-tin-indium alloy particles are low melting point alloys, and can melt and wrap on the surface of the spherical zinc powder at a temperature higher than its melting point to form a low melting point alloy coating.

[0007] Among them, the liquid epoxy resin composition in Component A is a mixture of Nanya NPEL128 epoxy resin, Nanya NPEF170 epoxy resin, epoxy active diluent, polymer dispersant, defoamer, and leveling agent, and the mass ratio of each component is 100:50:10:1:0.5:0.5. The mixed use of Nanya NPEL128 epoxy resin and Nanya NPEF170 epoxy resin can effectively reduce the low-temperature crystallinity of the epoxy resin composition, which is beneficial to the storage and construction of the product.

[0008] Among them, the active hydrogen equivalent of the modified liquid aromatic amine in Component B is 50 g / eq - 55 g / eq.

[0009] The manufacturing steps of Component A are as follows: The production equipment is a vacuum planetary mixer. According to the measurement ratio, the liquid epoxy resin composition and spherical zinc powder are put into the container of the vacuum planetary mixer, and at the same time, 0.5% of glutaric anhydride by the mass of the spherical zinc powder is added. The temperature of the container of the vacuum planetary mixer is raised to 105 °C, and it is stirred at high speed for 10 minutes, then cooled to 65 °C. Then, the bismuth-lead-tin-indium alloy particles in the measurement ratio are added into the container of the vacuum planetary mixer, and it is continuously stirred at high speed for 5 minutes, then cooled to 45 °C. Then, the fumed silica in the measurement ratio is continuously added into the container of the vacuum planetary mixer, and it is continuously stirred at high speed for 5 minutes. Then, 20% of distilled water by the mass of the liquid epoxy resin composition is added into the container of the vacuum planetary mixer, and it is continuously stirred at high speed for 5 minutes and then the stirring is stopped. The water located on the upper layer of the material is discharged, and then the vacuum planetary mixer is started for vacuum dehydration. During vacuum dehydration, high-speed stirring is maintained. After 20 minutes of vacuum dehydration, the material is discharged and packaged. The function of glutaric anhydride is to react with the oxide layer on the surface of the spherical zinc powder, remove the oxide layer, and improve the surface energy of the surface of the spherical zinc powder, which is beneficial to the wetting and wrapping of the bismuth-lead-tin-indium alloy after subsequent melting. The function of adding distilled water is to remove the excess glutaric anhydride and the generated water-soluble salts.

[0010] The usage method of this high thermal conductivity anti-corrosion coating is as follows: Mix Component A and Component B of this high thermal conductivity anti-corrosion coating according to a mass ratio of 18:1, and then apply the mixed coating on the treated substrate to prepare a coating. The coating is cured at room temperature for 24 hours, then heated to 65 °C and maintained for 10 minutes, the heating is stopped, and it is cooled to room temperature, and then the coating can be put into use.

[0011] The advantages and beneficial technical effects of the present invention are as follows: 1. This technical solution adopts a low-melting bismuth-lead-tin-indium alloy coating covering the surface of the main thermal conductive filler, spherical zinc powder. After the coating prepared is cured at room temperature and then heated at a low temperature, the bismuth-lead-tin-indium alloy coating melts, and the contact points of the thermal conductive filler fuse with each other, eliminating the interface thermal resistance, and qualitatively improving the thermal conductivity of the coating.

[0012] 2. Adding a small amount of anhydrous glutaric acid removes the oxide layer on the surface of spherical zinc powder, increases the surface energy of spherical zinc powder, and ensures that the bismuth-lead-tin-indium alloy with high surface tension after melting can effectively wet and wrap the spherical zinc powder to form a complete low-melting alloy coating.

[0013] 3. This technical solution uses a heatable vacuum planetary mixer to control the phase states of the bismuth-lead-tin-indium alloy and other components during the preparation of Component A, and the preparation process is simple and reliable. Specific embodiments

[0014] The present invention will be described in detail below through specific examples for easy understanding: Example 1: Put 19.2 kg of liquid epoxy resin composition (the mass ratio of Nanya NPEL128 epoxy resin, Nanya NPEF170 epoxy resin, epoxy active diluent, polymer dispersant, defoaming agent, and leveling agent is 100:50:10:1:0.5:0.5), 70 kg of spherical zinc powder with a median particle size of 20 ± 2 μm into the container of the vacuum planetary mixer, and at the same time add 0.35 kg of anhydrous glutaric acid. Heat the container of the vacuum planetary mixer to 105 °C, stir at high speed for 10 minutes, cool to 65 °C, then add 10 kg of bismuth-lead-tin-indium alloy particles with a melting point of 57 °C into the container of the vacuum planetary mixer, continue to stir at high speed for 5 minutes, then cool to 45 °C, continue to add 0.8 kg of fumed silica into the container of the vacuum planetary mixer, continue to stir at high speed for 5 minutes, then add 3.84 kg of distilled water into the container of the vacuum planetary mixer, continue to stir at high speed for 5 minutes and then stop stirring, drain the water on the upper layer of the material, and then start the vacuum planetary mixer for vacuum dehydration. Keep stirring at high speed during vacuum dehydration. After 20 minutes of vacuum dehydration, discharge and package to obtain Component A of the high thermal conductivity anti-corrosion coating.

[0015] Select a modified liquid aromatic amine with an active hydrogen equivalent of 50 g / eq as Component B of the high thermal conductivity coating. Mix Components A and B of the high thermal conductivity anti-corrosion coating according to a mass ratio of 18:1, and then use the mixed coating to prepare test samples. The test samples are cured at room temperature for 24 hours, then heated to 65 °C and maintained for 10 minutes, stop heating, cool to room temperature, and conduct tests. The test performances are as follows: Thermal conductivity: 10.5 W / m·K, ASTM D5470; Adhesion (carbon steel substrate): 9.5 MPa, ASTM D4541; Neutral salt spray test (carbon steel substrate): No blistering, no visible corrosion of the substrate, GB / T 10125.

[0016] Example 2: Put 17.2 kg of liquid epoxy resin composition (the mass ratio of Nanya NPEL128 epoxy resin, Nanya NPEF170 epoxy resin, epoxy active diluent, polymer dispersant, defoamer, and leveling agent is 100:50:10:1:0.5:0.5), 74 kg of spherical zinc powder with a median particle size of 20 ± 2 μm into the container of a vacuum planetary mixer, and simultaneously add 0.37 kg of anhydrous glutaric acid. Heat the container of the vacuum planetary mixer to 105 °C, stir at high speed for 10 minutes, cool to 65 °C, then add 8 kg of bismuth-lead-tin-indium alloy particles with a melting point of 57 °C into the container of the vacuum planetary mixer, continue to stir at high speed for 5 minutes, then cool to 45 °C, continue to add 0.8 kg of fumed silica into the container of the vacuum planetary mixer, continue to stir at high speed for 5 minutes, then add 3.44 kg of distilled water into the container of the vacuum planetary mixer, continue to stir at high speed for 5 minutes and then stop stirring, drain the water located on the upper layer of the material, then start the vacuum planetary mixer for vacuum dehydration, keep stirring at high speed during vacuum dehydration, after 20 minutes of vacuum dehydration, discharge and package to obtain Component A of the high thermal conductivity anti-corrosion coating.

[0017] Select a modified liquid aromatic amine with an active hydrogen equivalent of 55 g / eq as Component B of the high thermal conductivity coating. Mix Component A and Component B of the high thermal conductivity anti-corrosion coating according to a mass ratio of 18:1, and then use the mixed coating to prepare test samples. The test samples are cured at room temperature for 24 hours, then heated to 65 °C and held for 10 minutes, stop heating, cool to room temperature, and conduct tests. The test performances are as follows: Thermal conductivity: 10.9 W / m·K, ASTM D5470; Adhesion (carbon steel substrate): 9.3 MPa, ASTM D4541; Neutral salt spray test (carbon steel substrate): No blistering, no visible corrosion of the substrate, GB / T 10125.

Claims

1. A high thermal conductivity anti-corrosion coating, characterized in that: The coating consists of two components, A and B. Component A consists of the following components in mass percentage: Composition: spherical zinc powder: 70%-74%, bismuth-lead-tin-indium alloy particles: 8%-10%, liquid epoxy resin composition: 17.2%-19.2%, fumed silica: 0.8%; component B is a modified liquid aromatic amine, and the mass ratio of components A to B is 18:

1.

2. A high thermal conductivity anti-corrosion coating as claimed in claim 1, characterized in that The median particle size of the spherical zinc powder in the component A is 20±2 μm.

3. A high thermal conductivity anti-corrosion coating as claimed in claim 1, characterized in that The melting point of the bismuth-lead-tin-indium alloy particles in the A component is 57°C.

4. A high thermal conductivity anti-corrosion coating as claimed in claim 1, characterized in that The liquid epoxy resin composition in component A is a mixture of Nan Ya NPEL128 epoxy resin, Nan Ya NPEF170 epoxy resin, epoxy reactive diluent, polymer dispersant, defoamer and leveling agent, and the mass ratio of each component is 100:50:10:1:0.5:0.

5.

5. A high thermal conductivity anti-corrosion coating as claimed in claim 1, characterized in that The active hydrogen equivalent of the modified liquid aromatic amine in the B component is 50 g / eq-55 g / eq.

6. A high thermal conductivity anti-corrosion coating as claimed in claim 1, characterized in that The manufacturing steps of the component A are as follows: the production equipment is a vacuum planetary mixer, the liquid epoxy resin composition and spherical zinc powder are put into the vacuum planetary mixer container according to the metering ratio, and anhydrous glutaric acid of 0.5% by mass of the spherical zinc powder is added at the same time, the vacuum planetary mixer container is heated to 105°C, high-speed stirring is performed for 10 minutes, and the mixture is cooled to 65°C. Then, the bismuth-lead-tin-indium alloy particles of the metering ratio are added to the vacuum planetary mixer container, and high-speed stirring is continued for 5 minutes, and then the mixture is cooled to 45°C, and the metering ratio of fumed silica is continued to be added to the vacuum planetary mixer container, and high-speed stirring is continued for 5 minutes, and then 20% by mass of distilled water of the liquid epoxy resin composition is added to the vacuum planetary mixer container, and high-speed stirring is continued for 5 minutes, and then the stirring is stopped, and the water on the upper layer of the material is discharged, and then the vacuum planetary mixer is turned on for vacuum dehydration, and high-speed stirring is maintained during vacuum dehydration. After 20 minutes of vacuum dehydration, the material is discharged and packaged.

7. A high thermal conductivity anti-corrosion coating as claimed in claim 1, characterized in that The method for using the high thermal conductivity anti-corrosion coating is as follows: the A and B components of the high thermal conductivity anti-corrosion coating are mixed in a mass ratio of 18:1, and then the mixed coating is brushed on a treated substrate to prepare a coating, the coating is cured at room temperature for 24 hours, and then heated to 65°C and maintained for 10 minutes, the heating is stopped, and the coating is cooled to room temperature, and then it can be put into use.