Anti-static thermal insulation coating and preparation method thereof

Abstract

The application belongs to the field of thermal insulation coatings, and particularly relates to an anti-static thermal insulation coating and a preparation method thereof. The anti-static thermal insulation coating comprises: 12-18 wt% of a composite filler, 8-12 wt% of a system additive, 2-3 wt% of a post-treatment additive, and the rest of a liquid organic polysiloxane resin prepolymer base liquid; the composite filler comprises mica particles and silica wax microcapsules. The thermal insulation coating can autonomously construct a unique thermal insulation coating with a pore structure during the curing process, and the composite filler as the core cooperates with the pore structure to realize static electricity dissipation, and the partially closed pore structure cooperates with the composite filler to produce a good thermal insulation effect.

Description

TECHNICAL FIELD

[0001] The present application belongs to the field of thermal insulation coatings, and particularly relates to an anti-static thermal insulation coating and a preparation method thereof. BACKGROUND

[0002] Thermal insulation coatings are a very common and commonly used functional coating, which is widely used in thermal insulation of building structures and equipment. At present, the most important performance of thermal insulation coatings is safety and thermal insulation performance. Especially after several building exterior wall insulation layer fires in recent years, the safety of thermal insulation coatings has been further improved.

[0003] Therefore, at present, more and more thermal insulation coatings develop towards inorganic system, because they generally have higher safety, low organic volatile content in coating process and basically no burning risk after curing.

[0004] However, the advantages of organic system thermal insulation coatings cannot be ignored. For example, the cost of organic system thermal insulation coatings is lower, the coating and curing are faster, the film forming property is better, and most importantly, for some use scenarios, the thermal insulation coating formed by the thermal insulation coating is required to have better insulation performance, such as communication machine room, and the organic system thermal insulation coating is also more popular due to its excellent insulation performance and low cost advantage after curing.

[0005] Therefore, the special thermal insulation coating used in the communication machine room has new demand for anti-static. For this, the technical personnel in the field have carried out long-term research and development, and some thermal insulation coatings can achieve a certain degree of anti-static effect, but most of them are based on improving the static resistance of the thermal insulation coating. But my technical staff thinks that it is better to unblock than to block, and solves the static problem of the thermal insulation coating from another angle. SUMMARY

[0006] In order to solve the problem that the existing organic silicon resin system thermal insulation coating does not generally have good anti-static ability, and the existing thermal insulation coating anti-static performance improvement mostly considers from the angle of improving static resistance, thereby still having safety hazards and other problems, the present application provides an anti-static thermal insulation coating.

[0007] The main purpose of the present application is:

[0008] I. Good thermal insulation performance can be achieved;

[0009] II. Static dissipation can be effectively achieved under the condition of relative humidity of 40-55%, and static accumulation is avoided.

[0010] In order to achieve the above purpose, the present application adopts the following technical scheme.

[0011] An anti-static thermal insulation coating,

[0012] The anti-static thermal insulation coating comprises:

[0013] The composite filler is 12-18 wt%, the system additive is 8-12 wt%, the post-processing additive is 2-3 wt%, and the rest is the liquid organic polysiloxane resin prepolymer base solution;

[0014] The composite filler comprises mica particles, silica wax microcapsules, and aerogel microspheres. Preferably,

[0015] The mass ratio of the mica particles, the silica wax microcapsules, and the aerogel microspheres in the composite filler is 1:(7-9):(0.01-0.02);

[0016] The aerogel microspheres are polysiloxane aerogel microspheres.

[0017] Preferably,

[0018] The mica particles are subjected to sintering treatment.

[0019] When the mica particles are sintered, the mica powder and magnesium oxide are mixed in a mass ratio of 1:(0.08-0.12), then preheated at 160-180°C for 8-10 min, and then sintered at 650-700°C for 12-18 min to obtain the mica particles.

[0020] Preferably,

[0021] The mica powder has a mesh size of 80-200 mesh, and the magnesium oxide has a mesh size of 600-1000 mesh.

[0022] Preferably,

[0023] The silica wax microcapsules are prepared by the following method:

[0024] A petroleum ether solution of 0.5-0.8 mol / L tetraethyl orthosilicate is prepared, and PEG-PLC-PEG block copolymer is added to the solution as an oil phase liquid in a proportion of 0.15-0.25 mol / L. The paraffin is heated to melt, and then the molten paraffin and the oil phase liquid are mixed in a volume ratio of 1:(3-4) to form a mixed liquid and kept at a constant temperature of 60-80°C. After continuous stirring, the mixed liquid is mixed with 2-3 times the volume of water and sheared and stirred to form a suspension. The solid components in the suspension are filtered out and placed in an oxygen atmosphere and calcined at 200-220°C until the weight is constant, thereby obtaining the silica wax microcapsules.

[0025] Preferably,

[0026] The shearing and stirring process controls the stirring speed to be 3000-6000 rpm.

[0027] As preferred,

[0028] The system aid is composed of 8-12wt% curing agent, 1.5-2.5wt% amphiphilic surfactant and the rest of organic solvent;

[0029] The amphiphilic surfactant is lecithin;

[0030] The organic solvent is toluene.

[0031] As preferred,

[0032] The post-processing aid is toluene solution of non-ionic surfactant with concentration of 1-5wt%.

[0033] As preferred,

[0034] The anti-static thermal insulation coating is used in:

[0035] The composite filler, system aid and liquid organic polysiloxane resin prepolymer base solution are mixed and stirred uniformly, and then coated on the surface of the substrate to be treated, and then the surface loses stickiness to form a thermal insulation base layer after 45-75min of initial drying, and then the post-processing aid is coated on the surface of the thermal insulation base layer, and then completely dried and cured to form a thermal insulation coating.

[0036] A preparation method of an anti-static thermal insulation coating,

[0037] The method comprises:

[0038] The composite filler and liquid organic siloxane resin are mixed and packed into bag A, or the composite filler and liquid organic siloxane resin are packed into bag A-1 and bag A-2 respectively, the system aid is packed into bag B alone, and the post-processing agent is packed into bag C alone, and then packed for use.

[0039] For the present application, first of all, a composite filler system different from the filler such as ceramic microbeads or vacuum microbeads in conventional thermal insulation coatings is constructed. Because compared with structural thermal insulation and external wall thermal insulation, the application scene of the present coating does not require extremely high thermal resistance, but rather more requires the stability of equipment temperature, therefore the present application uses phase change material paraffin as the basis to construct the composite filler.

[0040] And different from conventional paraffin phase change capsules, the present application is first based on the amphiphilicity of block copolymer, and constructs a core-shell structure capsule with a silicon shell and a hollow paraffin core. In the construction process, the PEG segment of the PEG-PLC-PEG block copolymer is hydrophilic, and the hydrolysis of tetraethyl orthosilicate forms a silicon shell, while the PLC segment is oleophilic and links paraffin. The silicon shell can effectively coat the paraffin during the formation of the silicon shell. At the same time, due to the volatilization of part of the solvent before the closure of the shell layer in the subsequent calcination process, the silicon shell is closed, realizing the internal core of non-dense filling paraffin. The silicon paraffin microcapsules prepared have higher specific heat capacity due to the gas or partial vacuum environment contained in the internal core, and thus have higher thermal resistance. The phase change characteristics of paraffin can effectively control the temperature and avoid the occurrence of supercooling or overheating. In addition, based on the relatively unique preparation process of the present application, the silicon paraffin microcapsules prepared after low-temperature calcination still have a small amount of hydrophilic groups on the outer surface due to the phase interface assembly characteristics of the block copolymer. The retention of the hydrophilic group makes the silicon paraffin microcapsules of the present application have better ability to combine air and water molecules.

[0041] On this basis, the present application uses mica particles in combination with silicon paraffin microcapsules. Because the silicon paraffin microcapsules have a large thermal expansion coefficient of the silicon shell, they are prone to swelling after being heated, which will increase the risk of sharp discharge. Therefore, the present application uses oxygen-containing calcination to form silicon oxide on the surface of the silicon paraffin microcapsules during the preparation process, and cooperates with mica particles to "clamp and fix" them. Mica has a unique layered structure, and unlike montmorillonite and other layered structures, it has higher strength. However, mica and silicon dioxide are usually difficult to effectively combine and load. Therefore, the present application uses magnesium oxide to form sintering holes, and improves the hydrophilicity of mica. In addition, since mica is mainly composed of silicon and aluminum, Mg-Al or Mg-Si bonds will be formed between the layers during the calcination process with magnesium oxide, and magnesium element diffusion will occur, thereby forming sintering holes. The sintering holes can effectively load the silicon paraffin microcapsules through Mg-O-Si and Mg-Si bonds, so that the mica has good loading and fixing effect, and can effectively load the microcapsules, finally realizing the effect of inhibiting the volume expansion of the silicon paraffin microcapsules by mica.

[0042] On the other hand, the present application also requires that the thermal insulation coating can have the ability to dissipate static electricity after curing. This is also achieved based on the relatively unique porous structure of the thermal insulation coating of the present application. The system aid used in the present application is different from the conventional curing agent system, and an amphiphilic surfactant and an additional organic solvent are also introduced. It should be noted that the liquid organopolysiloxane resin prepolymer base fluid and the curing agent in the reaction aid used in the present application are both purchased from Dow Corning SYLGARD 184, and the A and B gums are purchased as a complete set. The A gum is a liquid organopolysiloxane resin prepolymer base fluid, and the B gum contains a catalyst and other components, which is the curing agent in the present application, and will not be described in detail. The present application introduces additional organic solvents and amphiphilic surfactants on the basis of conventional silicone resin, which can make the polysiloxane resin produce pore-forming effect during the curing process, and the formed pores are connected by the linking effect of mica and silica wax microcapsules in the composite filler, forming shrinkage connection points, resulting in partial closure and partial opening of the pores. The closed pores form a cavity-like heat insulation effect, which can improve the thermal insulation performance of the overall thermal insulation coating, and the open pores provide a basis for the static electricity release capability of the thermal insulation coating. Because polysiloxane resin has strong water repellency, it is difficult to dissipate static electricity by water molecules, but after the formation of pores, part of the composite filler can contact the water molecules in the air, i.e. the open pores can act as a water exchange channel, so that the water vapor in the external environment can contact the hydrophilic composite filler to dissipate static electricity. However, relying on only a few open pores, the actual anti-static effect is relatively limited, but if too much organic solvent and amphiphilic surfactant is introduced, the pore-forming effect will be too strong, which will reduce the strength of the thermal insulation coating and cause the structure to be loose, which may cause the composite filler to accumulate and not be evenly dispersed. Therefore, the present application further introduces a post-treatment aid.

[0043] The post-treatment aid is a non-ionic surfactant organic solution that can further swell and expand the pores based on polysiloxane after the initial drying of the thermal insulation coating, increase the pore size of the open pores without affecting the pore size of the closed pores, and increase the probability and area of the composite filler contacting the ambient water vapor, which can significantly improve the static electricity dissipation capability of the overall thermal insulation coating. However, the load stability and uniformity of the composite filler can be affected during this process, so the present application actually adds a small amount of polysiloxane aerogel balls to the composite filler. A small amount of polysiloxane aerogel balls can make the composite filler link more effectively with the polysiloxane resin matrix, and avoid translocation or even shedding of the composite filler due to the expansion effect during the subsequent post-treatment swelling and expansion process.

[0044] It can be seen that the core of the present application is the relatively unique composite filler, and based on the composite filler, the thermal insulation coating can autonomously build a thermal insulation coating with a pore structure during the curing process, so as to realize good thermal insulation and insulation performance, and also has static electricity dissipation capacity, which can realize slow static electricity dissipation in a conventional humidity (40-55% relative humidity) environment of a machine room, avoiding excessive static electricity accumulation to cause safety hazards.

[0045] The present application has the following advantages:

[0046] The thermal insulation coating of the present application can autonomously build a unique thermal insulation coating with a pore structure during the curing process, and the composite filler as the core cooperates with the pore structure to realize static electricity dissipation, and the partially closed pore structure cooperates with the composite filler to produce good thermal insulation effect. DETAILED DESCRIPTION

[0047] The present application will be further described and illustrated in detail with reference to specific examples. Those skilled in the art will be able to implement the present application based on these descriptions. In addition, the examples of the present application involved in the following descriptions are generally only a part of the examples of the present application, not all examples. Therefore, based on the examples in the present application, all other examples obtained by those skilled in the art without creative labor should be within the scope of protection of the present application.

[0048] Unless otherwise specified, the raw materials used in the examples of the present application are commercially available or can be obtained by those skilled in the art; unless otherwise specified, the methods used in the examples of the present application are methods mastered by those skilled in the art.

[0049] Unless otherwise specified, the polysiloxane aerogel beads used in the examples of the present application are purchased from Dupont de Nemours, Inc.

[0050] Example 1

[0051] An anti-static thermal insulation coating, respectively preparing mica particles and silica wax microcapsules;

[0052] Preparation of mica particles: 120 mesh mica powder and 840 mesh magnesium oxide were mixed in a mass ratio of 1:0.1 and preheated at 180℃ for 10 min, and then sintered at 700℃ for 15 min to obtain mica particles;

[0053] The mica particles obtained in this example were characterized, and the particle size was about 0.59±0.06mm;

[0054] Preparation of silica paraffin microcapsules: a 0.6 mol / L solution of ethyl silicate in petroleum ether was prepared, and PEG-PLC-PEG (polyethylene glycol-poly caprolactone-polyethylene glycol triblock copolymer) block copolymer was added to the oil phase solution at a ratio of 0.20 mol / L to prepare an oil phase solution. The paraffin was heated to melt, and then the molten paraffin was mixed with the oil phase solution at a volume ratio of 1:4 to form a mixed solution, which was kept at 70°C. After continuous stirring, the mixed solution was mixed with 3 times the volume of water and sheared at a high speed of 4500 rpm to form a suspension. The solid components in the suspension were filtered out and placed in an oxygen atmosphere for oxidation and calcination at 220°C until a constant weight was obtained, thereby obtaining silica paraffin microcapsules.

[0055] The silica paraffin microcapsules prepared in this example were characterized, and the average particle size was about 0.011±0.002 mm.

[0056] The composition of the specific heat preservation coating was as follows:

[0057] The composite filler was 15 wt%, the system additive was 10 wt%, the post-treatment additive was 2.5 wt%, and the balance was the liquid organic polysiloxane resin prepolymer base solution.

[0058] Among them:

[0059] The mass ratio of mica particles, silica paraffin microcapsules, and polysiloxane aerogel small balls with a particle size of ≤0.5 mm in the composite filler was 1:9:0.015.

[0060] The system additive was composed of 11 wt% curing agent, 2.0 wt% lecithin, and the balance of toluene.

[0061] The post-treatment additive was a 5 wt% polysorbate toluene solution.

[0062] The composite filler and the liquid organic siloxane resin were separately packaged into bag A-1 and bag A-2, the system additive was separately packaged into bag B, and the post-treatment agent was separately packaged into bag C, which were packed for use.

[0063] The anti-static heat preservation coating prepared in this example was coated on the surface of a glass substrate for performance testing, and the coating thickness of the heat preservation coating was 3 mm. When the anti-static heat preservation coating was used:

[0064] The composite filler, the system additive, and the liquid organic polysiloxane resin prepolymer base solution were mixed and stirred uniformly, and then coated on the surface of the substrate to be treated (test glass substrate). Then, the post-treatment additive was coated on the surface of the heat preservation base layer, and then completely dried and cured to form a heat preservation coating.

[0065] The characterization mainly included thermal conductivity characterization, volume resistivity characterization, and static electricity dissipation rate characterization.

[0066] wherein the thermal conductivity is characterized by a conventional standard method, the volume resistivity is characterized by a conventional standard method, and the static electricity dissipation rate is characterized by a conventional standard method using an induced static electricity tester in an environment with a relative humidity of 45% to measure the static electricity half-life of the thermal insulation coating.

[0067] The characterization results are shown in the following table.

[0068] thermal conductivity volume resistivity electrostatic half-life 0.093 w / (m·k) 1.36 x 10 14 Ω·cm 43.6s

[0069] As can be seen from the above characterization results, the thermal insulation coating has a low thermal conductivity, good thermal insulation effect, high volume resistivity, and good insulation, so that it can be effectively used for coating the outer surface of electronic equipment in a communication room. As can be seen from the static electricity half-life characterization results, the thermal insulation coating formed by curing the thermal insulation coating has good antistatic effect, can effectively and quickly dissipate static electricity, and can reduce the safety hazards caused by excessive accumulation of static electricity, and is very suitable for use in a communication room with a large number of high-power electronic devices.

[0070] Example 2

[0071] An antistatic thermal insulation coating, mica particles and silica wax microcapsules are prepared respectively;

[0072] Preparation of mica particles: 120 mesh mica powder and 840 mesh magnesium oxide are mixed in a mass ratio of 1:0.1 and preheated at 180°C for 10 minutes, then sintered at 700°C for 15 minutes to obtain mica particles;

[0073] Preparation of silica wax microcapsules: prepare a 0.6 mol / L tetraethyl orthosilicate solution in petroleum ether, and add PEG-PLC-PEG (polyethylene glycol-poly caprolactone-polyethylene glycol triblock copolymer) block copolymer to the oil phase liquid at a ratio of 0.20 mol / L. Heat the paraffin to melt, then mix the melted paraffin with the oil phase liquid at a volume ratio of 1:4 to form a mixed liquid and keep it at 70°C. After continuous stirring, mix it with 3 times the volume of water and shear at a high speed of 4500 rpm to form a suspension. Filter the solid components in the suspension and place them in an oxygen atmosphere at 220°C for oxidation calcination until the weight is constant, and the silica wax microcapsules are obtained.

[0074] The specific composition and ratio of the thermal insulation coating are as follows:

[0075] The composite filler is 12wt%, the system additive is 8wt%, the post-treatment additive is 2wt%, and the balance is the liquid organic polysiloxane resin prepolymer base liquid.

[0076] Wherein:

[0077] The mass ratio of mica particles, silica wax microcapsules and polysiloxane aerogel small balls with particle size ≤0.5mm in the composite filler is 1:9:0.015;

[0078] The system aid is composed of 11wt% curing agent, 2.0wt% lecithin and the rest of toluene;

[0079] The post-treatment aid is a toluene solution of polysorbate with a concentration of 5wt%.

[0080] The composite filler and the liquid organosiloxane resin are respectively packed into bag A-1 and bag A-2, the system aid is separately packed into bag B, and the post-treatment aid is separately packed into bag C, which are packed for use.

[0081] The anti-static thermal insulation coating prepared in this example is coated on the surface of a glass substrate for performance test, and the coating thickness of the thermal insulation coating is 3mm. When the anti-static thermal insulation coating is used:

[0082] The composite filler, the system aid and the liquid organopolysiloxane resin prepolymer base liquid are mixed and stirred uniformly, and then coated on the surface of the substrate to be treated. Then, the post-treatment aid is coated on the surface of the thermal insulation base layer after the surface loses tackiness after 60min of initial drying, and then completely dried and cured to form a thermal insulation coating.

[0083] The same characterization as in Example 1 is carried out, and the characterization results are shown in the following table.

[0084] thermal conductivity volume resistivity electrostatic half-life 0.098 w / (m·k) 1.42 x 10 14 Ω·cm 47.2s

[0085] From the above characterization results, the use amount of the composite filler, the system aid and the post-treatment aid is reduced, which leads to the increase of the thermal conductivity and the static half-life, indicating that the thermal insulation performance is decreased, and the antistatic ability is also weakened, but the volume resistivity is also improved to some extent, which shows that the composite filler and the strength of the pore-forming effect have a relatively obvious positive promoting effect on the thermal conductivity and the antistatic ability, but the researchers also believe that the addition of the composite filler will reduce the volume resistivity, which may be related to the shrinkage of the polysiloxane matrix.

[0086] Example 3

[0087] An anti-static thermal insulation coating, the preparation of mica particles and silica wax microcapsules is carried out respectively;

[0088] Preparation of mica particles: 120 mesh mica powder and 840 mesh magnesium oxide are mixed in a mass ratio of 1:0.1 and preheated at 180℃ for 10min, and then sintered at 700℃ for 15min to obtain mica particles;

[0089] Preparation of silica paraffin microcapsules: a 0.6 mol / L solution of ethyl orthosilicate in petroleum ether was prepared, and PEG-PLC-PEG (polyethylene glycol-poly caprolactone-polyethylene glycol triblock copolymer) block copolymer was added to the oil phase solution at a ratio of 0.20 mol / L to prepare an oil phase solution. The paraffin was heated to melt, and then mixed with the oil phase solution at a volume ratio of 1:4 to form a mixed solution, which was kept at 70°C. After continuous stirring, the mixed solution was mixed with 3 times the volume of water and stirred at a high speed of 4500 rpm to form a suspension. The solid components in the suspension were filtered and placed in an oxygen atmosphere for oxidation and calcination at 220°C until a constant weight was obtained, thereby obtaining silica paraffin microcapsules.

[0090] The specific composition of the heat preservation coating is as follows:

[0091] The composite filler is 18 wt%, the system additive is 12 wt%, the post-treatment additive is 3 wt%, and the remaining is liquid organic polysiloxane resin prepolymer base solution.

[0092] Wherein:

[0093] The mass ratio of mica particles, silica paraffin microcapsules, and polysiloxane aerogel small balls with a particle size of ≤0.5 mm in the composite filler is 1:9:0.015.

[0094] The system additive is composed of 11 wt% curing agent, 2.0 wt% lecithin, and the remaining toluene.

[0095] The post-treatment additive is a toluene solution of polysorbate with a concentration of 5 wt%.

[0096] The composite filler and liquid organic siloxane resin are separately packaged as bag A-1 and bag A-2, the system additive is separately packaged as bag B, and the post-treatment agent is separately packaged as bag C, which are packaged for use.

[0097] The anti-static heat preservation coating prepared in this example was coated on the surface of a glass substrate for performance testing. The coating thickness of the heat preservation coating was 3 mm. The anti-static heat preservation coating was used as follows:

[0098] The composite filler, system additive, and liquid organic polysiloxane resin prepolymer base solution were mixed and stirred uniformly, and then coated on the surface of the substrate to be treated. Then, the post-treatment additive was coated on the surface of the heat preservation base layer, and then completely dried and cured to form a heat preservation coating.

[0099] The same characterization as in Example 1 was performed, and the characterization results are shown in the following table.

[0100] thermal conductivity volume resistivity electrostatic half-life 0.092 w / (m·k) 1.27 x 10 14 Ω·cm 46.7s

[0101] From the above characterization results, further increase of the amount of composite filler leads to the decrease of thermal conductivity and volume resistivity, which shows that the composite filler has a relatively positive effect on improving the thermal insulation performance of the thermal insulation coating, and also confirms the above-mentioned view that the composite filler will lead to the decrease of the volume resistivity of the coating. In addition, from the static half-life characterization results, the static half-life of the thermal insulation coating of this example is relatively longer than that of Example 1, and the composite filler actually serves as the main effective component for dissipating static electricity, which should theoretically further improve the antistatic ability of the thermal insulation coating, but different characterization results are shown, and the researchers believe that this is because the composite filler of the present application has an inhibitory effect on the pore-forming process of the polysiloxane matrix, which limits the formation of the pore channel, thereby reducing the exchange path with the external water vapor and reducing the antistatic ability.

[0102] In addition, the phase change temperature interval and the phase change enthalpy of the thermal insulation coating samples formed by the coating plates of Examples 1-3 above were determined, and the determination was carried out on the heating process and the cooling process, respectively. The determination results are shown in the following table.

[0103]

[0104] From the above characterization results, the thermal insulation coating of the present application has good phase change heat storage capacity after curing to form a thermal insulation coating, can form effective temperature control within a certain temperature interval range, has a certain effect on preventing overheating or overcooling of the equipment room, and has a relatively high phase change enthalpy.

[0105] Comparative Example 1

[0106] An antistatic thermal insulation coating, which is different from Example 1 only in that the commercially available phase change material powder is used to replace the silica wax microcapsule prepared by the present application. The specific phase change material powder used is 28-degree phase change material powder (paraffin phase change microcapsule, standard parameters: phase change melting point 28±2.5℃, phase change enthalpy≥180J / g) purchased from Shanghai Xiyaxin Material Technology Co., Ltd. Mica particles are prepared.

[0107] Preparation of mica particles: 120-mesh mica powder and 840-mesh magnesium oxide are mixed in a mass ratio of 1:0.1 and preheated at 180℃ for 10 min, and then sintered at 700℃ for 15 min to obtain mica particles;

[0108] The specific composition and specific ratio of the thermal insulation coating are as follows:

[0109] Composite filler 15wt%, system additive 10wt%, post-treatment additive 2.5wt%, and the balance is liquid organic polysiloxane resin prepolymer base liquid;

[0110] Among them:

[0111] The mass ratio of mica particles, commercially available phase change material powder and polysiloxane aerogel small balls with particle size ≤0.5 mm in the composite filler is 1:9:0.015;

[0112] The system aid is composed of 11wt% curing agent, 2.0wt% lecithin and the rest of toluene;

[0113] The post-treatment aid is a toluene solution of polysorbate with a concentration of 5wt%.

[0114] The anti-static thermal insulation coating prepared in this example is coated on the surface of a glass substrate for performance testing, and the coating thickness of the thermal insulation coating is 3mm. The anti-static thermal insulation coating is used as follows:

[0115] The composite filler, system aid and liquid organic polysiloxane resin prepolymer base liquid are mixed and stirred uniformly, and then coated on the surface of the substrate to be treated. Then, after the thermal insulation base layer is formed by making it initially dry for 60 minutes until the surface loses tackiness, the post-treatment aid is coated on the surface of the thermal insulation base layer, and then completely dried and cured to form a thermal insulation coating.

[0116] The same characterization as in Example 1 is performed, and the characterization results are shown in the following table.

[0117]

[0118] From the above characterization results, the electrostatic half-life exceeds the maximum characterization time (120s), indicating that it does not exhibit significant antistatic ability, and also indicating that conventional paraffin phase change microcapsules do not have the ability to dissipate static charges. In addition, the volume resistivity and thermal conductivity of the thermal insulation coating formed after curing of the thermal insulation coating in this example are slightly higher than those of Example 1. It can be seen that conventional phase change material powder cannot effectively optimize the thermal insulation and insulation performance of the thermal insulation coating system of the present application.

[0119] Comparative Example 2

[0120] An anti-static thermal insulation coating, which differs from Example 1 only in that the mica particles are replaced by mica powder with the same average particle size, i.e. without magnesium oxide compounding and sintering, and the preparation of silica paraffin microcapsules is carried out;

[0121] Preparation of silica paraffin microcapsules: a 0.6 mol / L solution of ethyl orthosilicate in petroleum ether was prepared, and PEG-PLC-PEG (polyethylene glycol-poly (caprolactone)-polyethylene glycol triblock copolymer) block copolymer was added to the oil phase solution at a ratio of 0.20 mol / L. The paraffin was heated to melt, and then mixed with the oil phase solution at a volume ratio of 1:4 to form a mixed solution, which was kept at 70°C. After continuous stirring, the mixed solution was mixed with 3 times the volume of water and sheared at a high speed of 4500 rpm to form a suspension. The solid components in the suspension were filtered and placed in an oxygen atmosphere for oxidation and calcination at 220°C until a constant weight was obtained, thereby obtaining silica paraffin microcapsules.

[0122] The specific composition of the heat preservation coating is as follows:

[0123] The composite filler is 15 wt%, the system additive is 10 wt%, the post-treatment additive is 2.5 wt%, and the remaining is liquid organic polysiloxane resin prepolymer base solution.

[0124] Among them:

[0125] The mass ratio of mica, silica paraffin microcapsules and polysiloxane aerogel small balls with a particle size of ≤0.5 mm in the composite filler is 1:9:0.015.

[0126] The system additive is composed of 11 wt% curing agent, 2.0 wt% lecithin, and the remaining toluene.

[0127] The post-treatment additive is a toluene solution of polysorbate with a concentration of 5 wt%.

[0128] The composite filler, system additive and liquid organic polysiloxane resin prepolymer base solution were mixed and stirred uniformly, and then coated on the surface of the substrate to be treated. Then, the heat preservation base layer was formed after the surface lost tackiness after initial drying for 60 min. Then, the post-treatment additive was coated on the surface of the heat preservation base layer, and then completely dried and cured to form the heat preservation coating.

[0129] The same characterization as in Example 1 was performed, and the characterization results are shown in the following table.

[0130]

[0131] From the above characterization results, the mica particles in this example cannot effectively load the silica wax microcapsules without composite calcination of mica particles. In theory, the silica wax microcapsules should also have antistatic ability. However, the antistatic characterization results show that the comparative example 1 does not have good static dissipation ability, which is mainly due to the good compatibility and affinity of the silica wax microcapsules with the base fluid matrix. In the case that the mica particles cannot achieve fixation, the silica rubber is completely coated on the surface of the silica wax microcapsules, which prevents the effective removal of environmental water molecules to achieve static dissipation.

[0132] Comparative example 3

[0133] An antistatic type thermal insulation coating, respectively preparing mica particles and silica wax microcapsules;

[0134] Preparation of mica particles: mix 120 mesh mica powder and 840 mesh magnesium oxide at a mass ratio of 1:0.1 and preheat at 180°C for 10 min, then sinter at 700°C for 15 min to obtain mica particles;

[0135] Preparation of silica wax microcapsules: prepare a 0.6 mol / L tetraethyl orthosilicate solution in petroleum ether, and add PEG-PLC-PEG (polyethylene glycol-poly caprolactone-polyethylene glycol triblock copolymer) block copolymer to the oil phase liquid at a ratio of 0.20 mol / L. Heat the paraffin to melt, then mix the melted paraffin and the oil phase liquid at a volume ratio of 1:4 to form a mixed liquid and keep it at 70°C. After continuous stirring, mix it with 3 times the volume of water and shear at 4500 rpm to form a suspension. Filter out the solid components in the suspension and place them in an oxygen atmosphere at 220°C for oxidation calcination until the weight is constant, and the silica wax microcapsules are obtained.

[0136] The specific composition of the thermal insulation coating is:

[0137] 15wt% of composite filler, 10wt% of system additive, and the rest is liquid organic polysiloxane resin prepolymer base fluid;

[0138] Among them:

[0139] The mass ratio of mica particles, silica wax microcapsules and polysiloxane aerogel beads with particle size ≤0.5mm in the composite filler is 1:9:0.015;

[0140] The system additive is composed of 11wt% of curing agent, 2.0wt% of lecithin, and the rest of toluene.

[0141] The composite filler, system additive and liquid organic polysiloxane resin prepolymer base liquid are mixed and stirred uniformly, and then coated on the surface of the substrate to be treated. After complete drying and curing, the thermal insulation coating is formed.

[0142] The same characterization as in Example 1 was performed, and the characterization results are shown in the following table.

[0143]

[0144] From the above characterization results, it can be seen that the thermal insulation coating formed by curing the thermal insulation coating of the present example has little difference in phase transition temperature and phase transition heat enthalpy from Example 1, and the thermal conductivity coefficient is even further reduced, and the volume resistivity is also reduced, but the most obvious difference is that the antistatic ability of the thermal insulation coating formed by curing the thermal insulation coating of the present example is significantly reduced. This shows that the post-treatment additive can effectively expand the open pore structure on the surface of the coating after the coating is initially dried, thereby optimizing and improving the antistatic ability, but at the same time it can be found that the actual process has a certain negative impact on the thermal insulation performance of the thermal insulation coating, so the amount and timing of use of the post-treatment additive need to be relatively strictly controlled. If used too early, the internal closed pore structure may be opened, also leading to a decrease in thermal insulation performance, and if used too late, the swelling and expansion effect cannot be effectively achieved.

[0145] Comparative Example 4

[0146] A kind of antistatic thermal insulation coating, which is different from Example 1 only in that lecithin and toluene in the reaction additive are not used, i.e. no pore forming of the coating is performed;

[0147] Mica particles and silica wax microcapsules were prepared respectively;

[0148] Preparation of mica particles: 120 mesh mica powder was mixed with 840 mesh magnesium oxide at a mass ratio of 1:0.1 and preheated at 180°C for 10 min, and then sintered at 700°C for 15 min to obtain mica particles;

[0149] Preparation of silica wax microcapsules: a 0.6 mol / L tetraethyl orthosilicate solution in petroleum ether was prepared, and PEG-PLC-PEG (polyethylene glycol-poly-caprolactone-polyethylene glycol triblock copolymer) block copolymer was added to the oil phase liquid at a ratio of 0.20 mol / L to prepare an oil phase liquid. The paraffin was heated to melt, and then mixed with the oil phase liquid at a volume ratio of 1:4 to form a mixed liquid and kept at 70°C. After continuous stirring, it was mixed with 3 times the volume of water and sheared at a high speed of 4500 rpm to form a suspension. The solid components in the suspension were filtered out and calcined in an oxygen atmosphere at 220°C until the weight was constant, to obtain silica wax microcapsules.

[0150] The component ratio of the specific thermal insulation coating is:

[0151] 15wt% of the composite filler, 1.1wt% of the curing agent, 2.5wt% of the post-processing aid, and the rest of the liquid organic polysiloxane resin prepolymer base solution;

[0152] wherein:

[0153] The mass ratio of the mica particles, the silica wax microcapsules, and the polysiloxane aerogel small balls with a particle size of less than 0.5mm in the composite filler is 1:9:0.015;

[0154] The post-processing aid is a toluene solution of polysorbate with a concentration of 5wt%.

[0155] The composite filler, the curing agent, and the liquid organic polysiloxane resin prepolymer base solution are mixed and stirred uniformly, and then coated on the surface of the substrate to be treated. Then, the post-processing aid is coated on the surface of the thermal insulation base layer after the initial drying for 60 minutes until the surface loses tackiness to form a thermal insulation base layer. Then, the thermal insulation coating is formed after complete drying and curing.

[0156] The same characterization as in Example 1 is performed, and the characterization results are shown in the following table.

[0157]

[0158] From the above characterization results, the use of a simple curing agent instead of the reaction aid of the present application results in a comprehensive decline in the thermal insulation performance, insulation performance, and static electricity dissipation performance of the coating. The thermal insulation coating formed has a dense surface morphology, which cannot allow the composite filler particles to effectively contact the environmental water molecules through the fine pore structure, thereby realizing static electricity dissipation. Moreover, the thermal insulation coating no longer has an effective thermal insulation cavity (closed pore structure), so it can be seen that the reaction aid of the present application has a very significant impact on the thermal insulation coating of the present application. It is the key to optimizing the performance of the thermal insulation coating of the present application with the composite filler to realize efficient thermal insulation and static electricity prevention.

Claims

1. A kind of anti-static type thermal insulation coating, characterized in that, The anti-static type thermal insulation coating comprises: Composite filler 12-18 wt%, system aid 8-12 wt%, post-processing aid 2-3 wt%, and the balance is liquid organic polysiloxane resin prepolymer base solution. The composite filler comprises mica particles, silica wax microcapsules and aerogel microspheres. The mica particles are sintered. When the mica particles are sintered, the mica powder is mixed with magnesium oxide at a mass ratio of 1: (0.08-0.12), then preheated at 160-180 ℃ for 8-10 min, and then sintered at 650-700 ℃ for 12-18 min to obtain mica particles. The silica wax microcapsules are prepared by the following method: Prepare a 0.5-0.8 mol / L solution of tetraethyl orthosilicate in petroleum ether, add PEG-PLC-PEG block copolymer to the oil phase liquid at a ratio of 0.15-0.25 mol / L, heat the paraffin to melt, then mix the molten paraffin with the oil phase liquid at a volume ratio of 1: (3-4) to form a mixed liquid and keep it at 60-80 ℃, then mix it with 2-3 times the volume of water and shear to form a suspension, filter the solid components in the suspension and calcine in an oxygen atmosphere at 200-220 ℃ until the weight is constant to obtain silica wax microcapsules. 2.A kind of anti-static type thermal insulation coating according to claim 1, characterized in that, The mass ratio of mica particles, silica wax microcapsules and aerogel microspheres in the composite filler is 1: (7-9): (0.01-0.02). The aerogel microspheres are polysiloxane aerogel beads. 3.A kind of anti-static type thermal insulation coating according to claim 1, characterized in that, The mica powder has a mesh size of 80-200 mesh, and the magnesium oxide has a mesh size of 600-1000 mesh. 4.A kind of anti-static type thermal insulation coating according to claim 1, characterized in that, The shear stirring process controls the stirring speed at 3000-6000 rpm. 5.A kind of anti-static type thermal insulation coating according to claim 1, characterized in that, The system aid is composed of 8-12 wt% curing agent, 1.5-2.5 wt% amphiphilic surfactant and the balance of organic solvent. 6.A kind of anti-static type thermal insulation coating according to claim 1, characterized in that, The post-processing aid is a toluene solution of non-ionic surfactant with a concentration of 1-5 wt%. 7.A kind of anti-static type thermal insulation coating according to claim 1, characterized in that, The anti-static type thermal insulation coating is used as follows: Mix the composite filler, system aid and liquid organic polysiloxane resin prepolymer base solution and stir evenly, then coat on the surface of the substrate to be treated, then make it dry for 45-75 min to form a thermal insulation base layer, then coat the post-processing aid on the surface of the thermal insulation base layer, and then completely dry and cure to form a thermal insulation coating.

8. A method for producing the antistatic thermal insulation coating according to any one of claims 1 to 7, characterized by, the method comprising: mixing the composite filler and the liquid organosiloxane resin and packing them into a bag A, or packing the composite filler and the liquid organosiloxane resin into bags A-1 and A-2, respectively, packing the system aid into a bag B, packing the post-treatment agent into a bag C, and packing them for use.

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