Intumescent flame retardant heat insulating multilayer coating, heat insulating filler and preparation method

Abstract

The present disclosure provides an intumescent flame retardant heat insulating multilayer coating, heat insulating filler and preparation method, and relates to the technical field of flame retardant heat insulating coating. The intumescent flame retardant heat insulating multilayer coating comprises a first layer of coating and a second layer of coating configured from the inside to the outside, the first layer of coating is a physical intumescent heat insulating coating, and the second layer of coating is a chemical intumescent flame retardant heat insulating coating; the first layer of coating comprises: water-based styrene acrylic emulsion, water, hydroxyethyl cellulose, ethylene glycol, silicone defoamer, anti-flash rust agent, composite intumescent heat insulating filler and alcohol ester twelve; wherein the composite intumescent heat insulating filler comprises hollow glass microspheres and acrylic microspheres. The present disclosure can improve the intumescent flame retardant heat insulating effect of intumescent flame retardant heat insulating coating.

Description

Technical Field

[0001] The present disclosure relates to the technical field of flame retardant and thermal insulation coatings, and in particular, to an expandable flame retardant and thermal insulation multilayer coating, a method for preparing the expandable flame retardant and thermal insulation multilayer coating, a composite expandable thermal insulation filler, and a method for preparing the composite expandable thermal insulation filler. Background Art

[0002] Barrier-type thermal insulation coatings are widely used in the fields of construction, industrial manufacturing, etc. They can absorb heat under high temperature conditions in the fire scene to block the fire source and prevent the transfer of heat, playing the role of flame retardancy, heat preservation and heat insulation. Using flame retardant and thermal insulation coatings on buildings can effectively reduce the energy consumption of buildings, such as reducing heating energy consumption in winter and reducing air conditioning energy consumption in summer. Using thermal insulation coatings on industrial equipment such as pipelines and heat exchangers can reduce heat loss and improve energy efficiency. At the same time, using this kind of coating on fire-fighting facilities can effectively prevent the spread of fire, effectively isolate the fire source, and reduce losses.

[0003] Barrier thermal insulation coatings include intumescent flame retardant thermal insulation coatings. At present, after the coating surface of intumescent flame retardant thermal insulation coatings expands when exposed to open flames, the temperature of the bottom part of the coating that is not exposed to the open flame is not enough to make it expand further. The actual expansion multiple of the coating is often seriously insufficient, resulting in poor intumescent flame retardant thermal insulation effect.

[0004] It should be noted that the information disclosed in the above background technology section is only used to enhance the understanding of the background of the present disclosure, and therefore may include information that does not constitute the prior art known to ordinary technicians in the field. Summary of the invention

[0005] The purpose of the present disclosure is to provide an expandable flame retardant thermal insulation multilayer coating, a method for preparing the expandable flame retardant thermal insulation multilayer coating, a composite expandable thermal insulation filler and a method for preparing the composite expandable thermal insulation filler, thereby at least to a certain extent overcoming the problem of poor expandable flame retardant thermal insulation effect of the expandable flame retardant thermal insulation coating.

[0006] According to a first aspect of the present disclosure, there is provided an intumescent flame retardant heat insulating multilayer coating, which comprises a first layer of coating and a second layer of coating arranged from the inside to the outside, the first layer of coating being a physical intumescent heat insulating coating, and the second layer of coating being a chemical intumescent flame retardant heat insulating coating; the first layer of coating comprising, by mass: 5-15 parts of aqueous styrene acrylic emulsion, 30-50 parts of water, 0.1-1 parts of hydroxyethyl cellulose, 0.3-3 parts of ethylene glycol, 0.1-1 parts of silicone defoaming agent, 0.1-0.5 parts of anti-flash rust agent, 5-15 parts of composite intumescent heat insulating filler and 1-4 parts of alcohol ester twelve; wherein the composite intumescent heat insulating filler comprises hollow glass microspheres and acrylic microspheres.

[0007] Optionally, the aqueous styrene acrylic emulsion includes styrene and butyl acrylate; wherein the mass ratio of styrene to butyl acrylate is 1:1.4 to 1:2.

[0008] Optionally, the second coating layer includes, by mass, 10 parts of aqueous styrene acrylic emulsion, 8 parts of water, 5 parts of melamine-coated ammonium polyphosphate, 3 parts of melamine, 3 parts of pentaerythritol, 0.5 parts of titanium dioxide, 0.5 parts of expandable graphite, 0.5 parts of silicone defoamer and 0.1 parts of thickener.

[0009] According to a second aspect of the present disclosure, a method for preparing a composite expandable thermal insulation filler is provided, comprising: dissolving polyvinyl alcohol in water to obtain a polyvinyl alcohol solution; placing hollow glass microspheres in a closed drum-type reaction container, and spraying the polyvinyl alcohol solution on the surface of the hollow glass microspheres with a spray gun; adding the sprayed hollow glass microspheres and acrylic microspheres into an internal mixer and blending them to obtain a composite expandable thermal insulation filler.

[0010] Optionally, the weight ratio of polyvinyl alcohol to hollow glass microspheres is 0.05:1 to 0.2:1, and the weight ratio of hollow glass microspheres to acrylic microspheres is 1:1 to 5:1.

[0011] Optionally, the pressure of the spray gun is 0.05-0.3 MPa.

[0012] Optionally, the stirring frequency of the closed drum reaction vessel is 500-1000 r / min, the temperature of the closed drum reaction vessel is 30-50° C.; the mixing temperature of the internal mixer is less than or equal to 50° C., and the mixing time is 20-50 min.

[0013] According to a third aspect of the present disclosure, a composite expandable thermal insulation filler is provided. The composite expandable thermal insulation filler is prepared by any of the above-mentioned preparation methods of the composite expandable thermal insulation filler.

[0014] According to a fourth aspect of the present disclosure, a method for preparing an intumescent flame-retardant thermal insulation multilayer coating is provided, the intumescent flame-retardant thermal insulation multilayer coating comprising a first layer of coating and a second layer of coating configured from the inside to the outside, the first layer of coating being a physical intumescent thermal insulation coating, and the second layer of coating being a chemical intumescent flame-retardant thermal insulation coating; the method for preparing the first layer of coating comprising: adding, by mass, 30-50 parts of water, 0.1-1 parts of hydroxyethyl cellulose, 0.3-3 parts of ethylene glycol, 0.1-1 parts of silicone defoaming agents and 0.1-0.5 parts of anti-flash rust agents to 5-15 parts of an aqueous styrene-acrylic emulsion to obtain a first mixed solution; adding 5-15 parts of a composite intumescent thermal insulation filler and 1-4 parts of alcohol ester twelve to the first mixed solution to obtain the first layer of coating; wherein the composite intumescent thermal insulation filler comprises hollow glass microspheres and acrylic microspheres.

[0015] Optionally, the preparation method of the second layer of coating includes: mixing 10 parts of aqueous styrene acrylic emulsion, 8 parts of water and 0.5 parts of silicone defoamer, by mass, to obtain a second mixed solution; adding 5 parts of melamine-coated ammonium polyphosphate, 3 parts of melamine, 3 parts of pentaerythritol, 0.5 parts of titanium dioxide, and 0.5 parts of expandable graphite to the second mixed solution, and stirring to obtain a third mixed solution; adding 0.1 parts of thickener to the third mixed solution to obtain the second layer of coating.

[0016] In the scheme of the exemplary embodiment of the present disclosure, the composite expandable thermal insulation filler including hollow glass microspheres and acrylic microspheres has both expansion and thermal insulation properties. The composite expandable thermal insulation filler is applied to the expandable flame-retardant thermal insulation coating. On the one hand, the expanded acrylic microspheres have an excellent thermal insulation effect, which can reduce the thermal conductivity of the thermal insulation coating and improve the thermal insulation performance of the coating. On the other hand, the composite expandable thermal insulation filler can improve the uniformity of the expansion thickness of the coating, prevent the coating from being uneven and cracked, and help improve the quality of the coating. On the other hand, the present disclosure adopts a multi-layer combination of a physical expansion thermal insulation coating and a chemical expansion flame-retardant thermal insulation coating. Compared with the configuration of a single coating, the multi-layer coating of the present disclosure has a large expansion multiple, which can further improve the thermal insulation performance. In addition, the coating in the inner layer can not be easily destroyed by high temperature under the protection of the outer layer, and the heat transferred to the inner layer coating is sufficient to expand the expandable microspheres, further reducing the thermal conductivity.

[0017] It is to be understood that the foregoing general description and the following detailed description are exemplary and explanatory only and are not restrictive of the present disclosure. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] The accompanying drawings herein are incorporated into the specification and constitute a part of the specification, illustrate embodiments consistent with the present disclosure, and together with the specification are used to explain the principles of the present disclosure. Obviously, the accompanying drawings described below are only some embodiments of the present disclosure, and for ordinary technicians in this field, other accompanying drawings can be obtained based on these accompanying drawings without creative work.

[0019] Figure 1 A flow chart of a method for preparing a composite expandable thermal insulation filler according to an exemplary embodiment of the present disclosure is schematically shown.

[0020] Figure 2 A flow chart of a method for preparing a first layer of coating material as a physical expansion type thermal insulation coating material according to an exemplary embodiment of the present disclosure is schematically shown.

[0021] Figure 3A flow chart schematically shows a method for preparing a second layer of coating material as a chemical expansion type flame retardant thermal insulation coating material according to an exemplary embodiment of the present disclosure. DETAILED DESCRIPTION

[0022] Example embodiments will now be described more fully with reference to the accompanying drawings. However, example embodiments can be implemented in a variety of forms and should not be construed as being limited to the examples set forth herein; on the contrary, these embodiments are provided so that the present disclosure will be more comprehensive and complete, and the concepts of the example embodiments are fully conveyed to those skilled in the art. The described features, structures, or characteristics may be combined in any suitable manner in one or more embodiments. In the following description, many specific details are provided to provide a full understanding of the embodiments of the present disclosure. However, those skilled in the art will appreciate that the technical solutions of the present disclosure may be practiced while omitting one or more of the specific details, or other methods, processes, steps, etc. may be adopted. In other cases, known technical solutions are not shown or described in detail to avoid obscuring various aspects of the present disclosure.

[0023] In addition, the accompanying drawings are only schematic illustrations of the present disclosure and are not necessarily drawn to scale. The same reference numerals in the figures represent the same or similar parts, and thus their repeated descriptions will be omitted. The flowcharts shown in the accompanying drawings are only exemplary illustrations and do not necessarily include all the steps. For example, some steps can also be decomposed, while some steps can be combined or partially combined, so the actual execution order may change according to actual conditions. In addition, all the terms "first", "second", "third", etc. below are only for the purpose of distinction and should not be used as limitations of the present disclosure.

[0024] Barrier-type thermal insulation coatings usually include expansion type and non-expansion type. Non-expansion thermal insulation coatings have disadvantages such as insufficient thickness in one spraying and easy sagging. For expansion-type flame-retardant thermal insulation coatings, most of them currently have a single expansion mechanism, that is, when exposed to open flames, the volume expands due to chemical reactions to isolate the fire source to achieve the effect of flame retardancy and thermal insulation. Its expansion multiple is as high as dozens of times, and the thermal insulation temperature difference can reach more than 400°C. However, in actual use, after the coating surface expands when exposed to open flames, the temperature of the bottom part of the coating that is not in contact with the open flame is not enough to make it expand further. The actual expansion multiple of the coating is often seriously insufficient, and it cannot achieve the best expansion flame retardant and thermal insulation effect.

[0025] In order to improve the intumescent flame-retardant thermal insulation effect, the embodiments of the present disclosure provide a new composite intumescent thermal insulation filler, an intumescent flame-retardant thermal insulation multilayer coating comprising the composite intumescent thermal insulation filler, and methods for preparing the same.

[0026] In an exemplary embodiment of the present disclosure, the intumescent flame retardant thermal insulation multilayer coating comprises a first coating layer and a second coating layer configured from the inside out, the first coating layer is a physical intumescent thermal insulation coating, and the second coating layer is a chemical intumescent flame retardant thermal insulation coating.

[0027] It should be noted that the present disclosure does not limit the number of coating layers of the intumescent flame retardant thermal insulation multilayer coating, and these coating layers include the above-mentioned first coating layer and the second coating layer. As described above, it can be understood that relative to the first coating layer, the second coating layer can be an outer coating layer; relative to the second coating layer, the first coating layer can be an inner coating layer. In addition, based on the object to be coated (such as building materials, industrial materials, etc.), there may be other coating layers between the first coating layer and the object, or the first coating layer is a coating that is close to the object. There may be other coating layers between the first coating layer and the second coating layer, or the second coating layer may be applied on the first coating layer. Other coating layers may be applied in addition to the second layer. The above-mentioned other coating layers disclosed in the present disclosure are physical intumescent thermal insulation coatings or chemical intumescent flame retardant thermal insulation coatings, and the present disclosure does not limit this.

[0028] For example, the intumescent flame retardant heat insulating multilayer coating only includes a first coating layer and a second coating layer arranged from the inside to the outside. In this case, the intumescent flame retardant heat insulating multilayer coating is a double-layer coating. Specifically, the first coating layer is applied to the object to be coated, and then the second coating layer is applied on the first coating layer.

[0029] In parts by mass, the first layer of coating may include: 5-15 parts of aqueous styrene acrylic emulsion, 30-50 parts of water, 0.1-1 parts of hydroxyethyl cellulose, 0.3-3 parts of ethylene glycol, 0.1-1 parts of silicone defoaming agent, 0.1-0.5 parts of anti-flash rust agent, 5-15 parts of composite expandable thermal insulation filler and 1-4 parts of alcohol ester dodecahydrate.

[0030] It is understandable that the first layer of coating can be composed of the above raw materials. In addition, in addition to the above raw materials, the first layer of coating can also include other raw materials, which is not limited by the present disclosure.

[0031] The composite expandable heat-insulating filler may include hollow glass microspheres and acrylic microspheres.

[0032] The aqueous styrene-acrylic emulsion may include styrene and butyl acrylate, wherein the mass ratio of styrene to butyl acrylate is, for example, 1:1.4 to 1:2.

[0033] Still calculated by mass, the second coating layer may include: 10 parts of aqueous styrene acrylic emulsion, 8 parts of water, 5 parts of melamine-coated ammonium polyphosphate, 3 parts of melamine, 3 parts of pentaerythritol, 0.5 parts of titanium dioxide, 0.5 parts of expandable graphite, 0.5 parts of silicone defoamer and 0.1 parts of thickener.

[0034] The implementation principle is explained by taking the example of an intumescent flame retardant and heat insulating multilayer coating that only includes the first layer of coating and the second layer of coating. Specifically, the intumescent flame retardant and heat insulating double-layer coating has a special expansion structure. The outer layer is a chemical intumescent flame retardant and heat insulating coating. When encountering an open flame, the coating undergoes a rapid chemical reaction to produce a large number of bubbles and surface ceramicization. The porous and loose internal structure can play a role in flame retardancy and heat insulation. The ceramic layer on the surface protects the internal structure from being eroded and damaged by flames. The inner layer is a physical intumescent thermal insulation coating. During the heating process, the volume of the expanded microspheres increases several times, producing countless new independent closed-cell hollow microsphere structures, which further reduces the thermal conductivity of the coating and effectively prevents heat conduction. Although the temperature transferred to the interior is not enough to expand the outer layer of coating, it is enough to expand the inner layer of coating when heated.

[0035] Reference below Figure 1 The preparation method of the composite expandable thermal insulation filler according to the exemplary embodiment of the present disclosure is described. Figure 1 The preparation method of the composite expandable thermal insulation filler according to the embodiment of the present disclosure may include the following steps:

[0036] S12. Dissolving polyvinyl alcohol in water to obtain a polyvinyl alcohol solution.

[0037] In an exemplary embodiment of the present disclosure, polyvinyl alcohol (PVA) can be added to hot water at room temperature to dissolve quickly and then slowly cooled to room temperature to obtain a polyvinyl alcohol solution. The present disclosure does not limit the specific water temperature of the hot water, for example, the water temperature range is 50-90°C.

[0038] S14. Place the hollow glass microspheres in a closed drum-type reaction container, and use a spray gun to spray the polyvinyl alcohol solution onto the surface of the hollow glass microspheres.

[0039] In an exemplary embodiment of the present disclosure, the closed drum-type reaction container is continuously stirred, and the stirring frequency is, for example, 500-1000 r / min. In addition, the temperature of the closed drum-type reaction container is, for example, 30-50°C.

[0040] In the embodiment of the present disclosure, the polyvinyl alcohol solution obtained in step S12 is sprayed onto the surface of the hollow glass microspheres using a spray gun, and the pressure of the spray gun can be set to 0.05-0.3 MPa.

[0041] In order to precisely control the preparation process to at least achieve the purpose of improving the thermal insulation effect, the weight ratio of the polyvinyl alcohol to the hollow glass microspheres can be set to 0.05:1 to 0.2:1.

[0042] S16. Add the sprayed hollow glass microspheres and acrylic microspheres into an internal mixer and blend them to obtain a composite expandable thermal insulation filler.

[0043] In an exemplary embodiment of the present disclosure, the internal mixing temperature of the internal mixer may be set to be less than or equal to 50° C., and the internal mixing time may be, for example, 20-50 min.

[0044] Furthermore, the embodiments of the present disclosure also provide a composite expandable thermal insulation filler, which is prepared by the above-mentioned preparation method of the composite expandable thermal insulation filler.

[0045] Furthermore, the embodiments of the present disclosure also provide a method for preparing an intumescent flame retardant and heat insulating multi-layer coating. The intumescent flame retardant and heat insulating multi-layer coating is as described above and will not be described in detail herein.

[0046] Reference below Figure 2 The method for preparing the first layer of the physical expansion type thermal insulation coating according to the exemplary embodiment of the present disclosure is described. Figure 2 , by weight, the preparation method of the first coating layer comprises the following steps:

[0047] S22. 30-50 parts of water, 0.1-1 parts of hydroxyethyl cellulose, 0.3-3 parts of ethylene glycol, 0.1-1 parts of silicone defoamer and 0.1-0.5 parts of anti-flash rust agent are added to 5-15 parts of aqueous styrene acrylic emulsion to obtain a first mixed solution.

[0048] S24. 5-15 parts of the composite expandable heat-insulating filler and 1-4 parts of the alcohol ester dodecapolymer are added to the first mixed solution to obtain a first coating layer.

[0049] Specifically, as described above, the composite expandable thermal insulation filler may include hollow glass microspheres and acrylic microspheres.

[0050] The embodiment of the present disclosure mixes different raw materials in steps, which helps to disperse the raw materials and achieve the purpose of improving thermal insulation performance.

[0051] Figure 3 The flowchart of the method for preparing the second layer of coating material as a chemical expansion type flame retardant heat insulation coating material according to an exemplary embodiment of the present disclosure is schematically shown. Figure 3 , by weight, the preparation method of the second coating layer comprises the following steps:

[0052] S32. 10 parts of an aqueous styrene acrylic emulsion, 8 parts of water and 0.5 parts of an organosilicon defoamer are mixed to obtain a second mixed solution.

[0053] S34. 5 parts of melamine-coated ammonium polyphosphate, 3 parts of melamine, 3 parts of pentaerythritol, 0.5 parts of titanium dioxide, and 0.5 parts of expandable graphite are added to the second mixed solution, and stirred to obtain a third mixed solution.

[0054] S36. 0.1 parts of a thickener is added to the third mixed solution to obtain a second coating layer.

[0055] Similarly, mixing different raw materials in steps helps to disperse the raw materials to achieve the purpose of improving thermal insulation performance.

[0056] The following examples illustrate the preparation process of the composite expandable thermal insulation filler and the expandable flame retardant thermal insulation multilayer coating disclosed in the present invention. The following examples 1 to 4 are exemplary descriptions of the preparation of the composite expandable thermal insulation filler, and examples 5 to 8 are exemplary descriptions of the preparation of the expandable flame retardant thermal insulation multilayer coating.

[0057] Table 1 shows the comparison results of the contents of hollow glass microspheres, acrylic microspheres, and polyvinyl alcohol solutions in Examples 1 to 4.

[0058] Table 1

[0059]

[0060] Example 1

[0061] First, at room temperature, polyvinyl alcohol was slowly added to water at 1000 r / min, and the temperature was raised to 90°C while mixing, and stirring was continued for 5 hours, and then cooled to room temperature to obtain a polyvinyl alcohol solution with a mass fraction of 4%. 125g of the polyvinyl alcohol solution was placed in a high-pressure spray gun, and the spraying pressure was set to 0.05MPa.

[0062] When 100 g of hollow glass microspheres were placed in a closed drum-type reaction container, the polyvinyl alcohol solution was uniformly sprayed onto the surface of the hollow glass microspheres using a spray gun, wherein the stirring frequency of the closed drum-type reaction container was 500 r / min and the temperature was 30° C.

[0063] Next, the sprayed hollow glass microspheres and 25g of acrylic microspheres are added to an internal mixer for mixing, and the mixing temperature is controlled below 50°C for 20 minutes. The particle size of the acrylic microspheres is 10-15μm. The mixing temperature can be controlled at 10°C to 50°C, for example, 10°C, 30°C, 40°C, 45°C or 50°C.

[0064] Then, the composite expandable heat-insulating filler is obtained after drying at room temperature.

[0065] Example 2

[0066] First, at room temperature, polyvinyl alcohol was slowly added to water at 1000 r / min, the temperature was raised to 90°C while mixing, stirring was continued for 5 hours, and the mixture was cooled to room temperature to obtain a polyvinyl alcohol solution with a mass fraction of 4%. 250 g of the polyvinyl alcohol solution was placed in a high-pressure spray gun, and the spraying pressure was set to 0.1 MPa.

[0067] When 100 g of hollow glass microspheres were placed in a closed drum-type reaction container, the polyvinyl alcohol solution was uniformly sprayed onto the surface of the hollow glass microspheres using a spray gun, wherein the stirring frequency of the closed drum-type reaction container was 700 r / min and the temperature was 40° C.

[0068] Next, the sprayed hollow glass microspheres and 50g of acrylic microspheres are added to an internal mixer for mixing, and the mixing temperature is controlled below 50°C for 30 minutes. The particle size of the acrylic microspheres is 10-15μm. The mixing temperature can be controlled at 10°C to 50°C, for example, 10°C, 30°C, 40°C, 45°C or 50°C.

[0069] Then, the composite expandable heat-insulating filler is obtained after drying at room temperature.

[0070] Example 3

[0071] First, at room temperature, polyvinyl alcohol was slowly added to water at 1000 r / min, the temperature was raised to 90°C while mixing, stirring was continued for 5 hours, and the solution was cooled to room temperature to obtain a polyvinyl alcohol solution with a mass fraction of 4%. 375 g of the polyvinyl alcohol solution was placed in a high-pressure spray gun, and the spraying pressure was set to 0.2 MPa.

[0072] When 100 g of hollow glass microspheres were placed in a closed drum-type reaction container, the polyvinyl alcohol solution was uniformly sprayed onto the surface of the hollow glass microspheres using a spray gun, wherein the stirring frequency of the closed drum-type reaction container was 850 r / min and the temperature was 40° C.

[0073] Next, the sprayed hollow glass microspheres and 75g of acrylic microspheres are added to an internal mixer for mixing, and the mixing temperature is controlled below 50°C for 40 minutes. The particle size of the acrylic microspheres is 10-15μm. The mixing temperature can be controlled at 10°C to 50°C, for example, 10°C, 30°C, 40°C, 45°C or 50°C.

[0074] Then, the composite expandable heat-insulating filler is obtained after drying at room temperature.

[0075] Example 4

[0076] First, at room temperature, polyvinyl alcohol was slowly added to water at 1000 r / min, and the mixture was heated to 90°C while being mixed, and stirred for 5 hours, and cooled to room temperature to obtain a polyvinyl alcohol solution with a mass fraction of 4%. 500 g of the polyvinyl alcohol solution was placed in a high-pressure spray gun, and the spraying pressure was set to 0.3 MPa.

[0077] When 100 g of hollow glass microspheres were placed in a closed drum-type reaction container, the polyvinyl alcohol solution was uniformly sprayed onto the surface of the hollow glass microspheres using a spray gun, wherein the stirring frequency of the closed drum-type reaction container was 1000 r / min and the temperature was 50° C.

[0078] Next, the sprayed hollow glass microspheres and 100g of acrylic microspheres are added to an internal mixer for mixing, and the mixing temperature is controlled below 50°C for 50 minutes. The particle size of the acrylic microspheres is 10-15μm. The mixing temperature can be controlled at 10°C to 50°C, for example, 10°C, 30°C, 40°C, 45°C or 50°C.

[0079] Then, the composite expandable heat-insulating filler is obtained after drying at room temperature.

[0080] The preparation scheme of the intumescent flame retardant and heat insulating multi-layer coating disclosed in the present invention is described below through Examples 5 to 8 and Comparative Examples 1 and 2.

[0081] Example 5

[0082] 30g of water, 0.1g of thickener, 0.3g of antifreeze agent, 0.1g of silicone defoamer and 0.12g of anti-flash rust agent were added to 5g of aqueous styrene-acrylic emulsion in sequence, and mixed and stirred at 400r / min at room temperature for 20min. Then, 5g of composite expandable thermal insulation filler was added to the above-mentioned mixed system in three batches, and after stirring evenly, 1g of film-forming aid was added, and stirred at 2000r / min for 30min to obtain the first layer of coating as a physical expansion type thermal insulation coating.

[0083] Among them, the ratio of styrene and butyl acrylate monomers in the aqueous styrene-acrylic emulsion is 1:1.4, the thickener is hydroxyethyl cellulose, the antifreeze agent is ethylene glycol, the composite expandable thermal insulation filler is obtained by the above-mentioned Example 1, the film-forming aid is alcohol ester twelve, the coating heating temperature is 60°C, and the time is 10 minutes.

[0084] 10g of aqueous styrene acrylic emulsion, 8g of water and 0.5g of silicone defoamer were mixed evenly, and then 5g of melamine-coated ammonium polyphosphate, 3g of melamine, 3g of pentaerythritol, 0.5g of titanium dioxide and 0.5g of expandable graphite were added thereto in sequence, and stirred at 2000r / min for 30min, and 0.1g of thickener was added to adjust the viscosity to obtain the second layer of coating as a chemical expansion type flame retardant thermal insulation coating.

[0085] Example 6

[0086] 35g of water, 0.4g of thickener, 1.2g of antifreeze agent, 0.4g of silicone defoamer and 0.24g of anti-flash rust agent were added to 8g of aqueous styrene acrylic emulsion in sequence, and mixed and stirred at 400r / min at room temperature for 20min. Then 8g of composite expandable thermal insulation filler was added to the above-mentioned mixed system in three batches, and after stirring evenly, 2g of film-forming aid was added, and stirred at 2000r / min for 30min to obtain the first layer of coating as a physical expansion type thermal insulation coating.

[0087] The ratio of styrene to butyl acrylate monomers in the aqueous styrene-acrylic emulsion is 1:1.6, the composite expandable thermal insulation filler is obtained in Example 2, the coating heating temperature is 65° C., and the heating time is 13 minutes.

[0088] 10g of aqueous styrene acrylic emulsion, 8g of water and 0.5g of silicone defoamer were mixed evenly, and then 5g of melamine-coated ammonium polyphosphate, 3g of melamine, 3g of pentaerythritol, 0.5g of titanium dioxide and 0.5g of expandable graphite were added thereto in sequence, and stirred at 2000r / min for 30min, and 0.1g of thickener was added to adjust the viscosity to obtain the second layer of coating as a chemical expansion type flame retardant thermal insulation coating.

[0089] Example 7

[0090] 40g of water, 0.7g of thickener, 2.1g of antifreeze agent, 0.7g of silicone defoamer and 0.36g of anti-flash rust agent were added to 11g of aqueous styrene-acrylic emulsion in sequence, and mixed and stirred at 400r / min for 20min at room temperature. Then 11g of composite expandable thermal insulation filler was added to the above-mentioned mixed system in three batches, and after stirring evenly, 3g of film-forming aid was added, and stirred at 2000r / min for 30min to obtain the first layer of coating as a physical expansion type thermal insulation coating.

[0091] The ratio of styrene to butyl acrylate monomers in the aqueous styrene-acrylic emulsion is 1:1.8, the composite expandable thermal insulation filler is obtained in Example 3, the coating heating temperature is 70° C., and the heating time is 16 min.

[0092] 10g of aqueous styrene acrylic emulsion, 8g of water and 0.5g of silicone defoamer were mixed evenly, and then 5g of melamine-coated ammonium polyphosphate, 3g of melamine, 3g of pentaerythritol, 0.5g of titanium dioxide and 0.5g of expandable graphite were added thereto in sequence, and stirred at 2000r / min for 30min, and 0.1g of thickener was added to adjust the viscosity to obtain the second layer of coating as a chemical expansion type flame retardant thermal insulation coating.

[0093] Example 8

[0094] 50g of water, 1g of thickener, 3g of antifreeze agent, 1g of silicone defoamer and 0.5g of anti-flash rust agent are added to 15g of aqueous styrene-acrylic emulsion in sequence, and mixed and stirred at 400r / min for 20min at room temperature. Then, 15g of composite expandable thermal insulation filler is added to the above-mentioned mixed system in three batches, and after stirring evenly, 4g of film-forming aid is added, and stirred at 2000r / min for 30min to obtain the first layer of coating as a physical expansion type thermal insulation coating.

[0095] The ratio of styrene to butyl acrylate monomers in the aqueous styrene-acrylic emulsion is 1:2, the composite expandable thermal insulation filler is obtained in Example 4, the coating heating temperature is 80° C., and the heating time is 20 min.

[0096] 10g of aqueous styrene acrylic emulsion, 8g of water and 0.5g of silicone defoamer were mixed evenly, and then 5g of melamine-coated ammonium polyphosphate, 3g of melamine, 3g of pentaerythritol, 0.5g of titanium dioxide and 0.5g of expandable graphite were added thereto in sequence, and stirred at 2000r / min for 30min, and 0.1g of thickener was added to adjust the viscosity to obtain the second layer of coating as a chemical expansion type flame retardant thermal insulation coating.

[0097] Comparative Example 1

[0098] 40g of water, 0.7g of thickener, 2.1g of antifreeze agent, 0.7g of silicone defoamer and 0.36g of anti-flash rust agent were added to 11g of aqueous styrene-acrylic emulsion in sequence, and mixed and stirred at 400r / min at room temperature for 20min. Then, 8.8g of hollow glass microspheres and 2.2g of acrylic microspheres were mixed and added to the above mixed system in three batches. After stirring evenly, 3g of film-forming aid was added, and stirred at 2000r / min for 30min to obtain an inner layer of physical expansion type thermal insulation coating.

[0099] In Comparative Example 1, except for the composite expandable thermal insulation filler, other conditions are consistent with those of the above-mentioned Example 7.

[0100] Comparative Example 2

[0101] 40g of water, 0.7g of thickener, 2.1g of antifreeze agent, 0.7g of silicone defoamer and 0.36g of anti-flash rust agent were added to 11g of aqueous styrene-acrylic emulsion in sequence, and mixed and stirred at 400r / min for 20min at room temperature. Then 11g of composite expandable thermal insulation filler was added to the above-mentioned mixed system in three batches, and after stirring evenly, 3g of film-forming aid was added, and stirred at 2000r / min for 30min to obtain an inner layer of physical expansion type thermal insulation coating.

[0102] In Comparative Example 2, the ratio of styrene to butyl acrylate monomers in the aqueous styrene-acrylic emulsion is 1:1, and other conditions are consistent with those in Example 7.

[0103] For the first layer of coating, Examples 5 to 8 and Comparative Examples 1 and 2 are compared by thermal conductivity, expansion rate and appearance, as shown in Table 2:

[0104] Table 2

[0105]

[0106] The thermal conductivity test refers to GB / T 10297-2005 "Determination of thermal conductivity of non-metallic solid materials - hot wire method". The expansion rate test is to prepare the coating into a uniform film by spraying, then heat and expand it, and measure the ratio of the thickness of the thermal insulation coating before and after expansion.

[0107] By analyzing the test data in Table 2, it can be seen that the expansion rate of the intumescent flame-retardant and heat-insulating double-layer coating obtained in Example 7 is increased by 23 times, and the thermal conductivity is reduced by 29% compared with that in Comparative Example 1. At the same time, the surface of the coating prepared by the composite intumescent heat-insulating filler is more uniform after expansion, without large fluctuations. This shows that by compounding hollow glass microspheres and expandable acrylic microspheres and then adding them to the coating, the dispersion uniformity, expansion uniformity and thermal insulation properties of the expansion components can be greatly improved. On the basis of not losing the insulation performance of the filler, the improvement of dispersion uniformity and expansion uniformity also helps to improve the composite strength of the filler.

[0108] In addition, by comparing Example 7 with Comparative Example 2, it can be seen that the hardness of the aqueous styrene-acrylic emulsion is also an important factor affecting expansion. Increasing the amount of butyl acrylate in the aqueous styrene-acrylic emulsion can improve the flexibility of the aqueous styrene-acrylic emulsion and facilitate expansion.

[0109] It should be noted that although the steps of the method in the present disclosure are described in a specific order in the drawings, this does not require or imply that the steps must be performed in this specific order, or that all the steps shown must be performed to achieve the desired results. Additionally or alternatively, some steps may be omitted, multiple steps may be combined into one step, and / or one step may be decomposed into multiple steps, etc.

[0110] In addition, the above-mentioned figures are only schematic illustrations of the processes included in the method according to the exemplary embodiments of the present disclosure, and are not intended to be limiting. It is easy to understand that the processes shown in the above-mentioned figures do not indicate or limit the time sequence of these processes. In addition, it is also easy to understand that these processes can be performed synchronously or asynchronously, for example, in multiple modules.

[0111] Those skilled in the art will readily appreciate other embodiments of the present disclosure after considering the specification and practicing what is disclosed herein. This application is intended to cover any variations, uses, or adaptations of the present disclosure that follow the general principles of the present disclosure and include common knowledge or customary technical means in the art that are not disclosed in the present disclosure. The specification and embodiments are to be considered merely as exemplary, and the true scope and spirit of the present disclosure are indicated by the claims.

[0112] It should be understood that the present disclosure is not limited to the exact structures that have been described above and shown in the drawings, and that various modifications and changes may be made without departing from the scope thereof. The scope of the present disclosure is limited only by the appended claims.

Claims

1. An intumescent flame retardant heat insulating multilayer coating, characterized in that: The intumescent flame retardant heat insulating multilayer coating comprises a first coating layer and a second coating layer arranged from the inside to the outside, the first coating layer is a physical intumescent heat insulating coating, and the second coating layer is a chemical intumescent flame retardant heat insulating coating; The first coating layer comprises, by mass, 5-15 parts of water-based styrene-acrylic emulsion, 30-50 parts of water, 0.1-1 parts of hydroxyethyl cellulose, 0.3-3 parts of ethylene glycol, 0.1-1 parts of silicone defoamer, 0.1-0.5 parts of anti-flash rust agent, 5-15 parts of composite expandable thermal insulation filler and 1-4 parts of alcohol ester dodecahydrate; the composite expandable thermal insulation filler comprises hollow glass microspheres and acrylic microspheres; the water-based styrene-acrylic emulsion comprises styrene and butyl acrylate, and the mass ratio of styrene to butyl acrylate is 1:1.4 to 1:2; The preparation process of the composite expandable thermal insulation filler includes: dissolving polyvinyl alcohol in water to obtain a polyvinyl alcohol solution; placing hollow glass microspheres in a closed drum-type reaction container, and spraying the polyvinyl alcohol solution on the surface of the hollow glass microspheres with a spray gun; adding the sprayed hollow glass microspheres and acrylic microspheres into an internal mixer for blending to obtain a composite expandable thermal insulation filler; the weight ratio of the polyvinyl alcohol to the hollow glass microspheres is 0.05:1 to 0.2:1, and the weight ratio of the hollow glass microspheres to the acrylic microspheres is 1:1 to 5:

1.

2. The intumescent flame retardant and heat insulating multi-layer coating according to claim 1, characterized in that: The second coating layer includes, by mass, 10 parts of water-based styrene acrylic emulsion, 8 parts of water, 5 parts of melamine-coated ammonium polyphosphate, 3 parts of melamine, 3 parts of pentaerythritol, 0.5 parts of titanium dioxide, 0.5 parts of expandable graphite, 0.5 parts of silicone defoamer and 0.1 parts of thickener.

3. The intumescent flame retardant and heat insulating multi-layer coating according to claim 1, characterized in that: The pressure of the spray gun is 0.05-0.3 MPa.

4. The intumescent flame retardant and heat insulating multi-layer coating according to claim 1, characterized in that: The stirring frequency of the closed drum-type reaction container is 500-1000 r / min, and the temperature of the closed drum-type reaction container is 30-50° C.; The internal mixing temperature of the internal mixer is less than or equal to 50° C., and the internal mixing time is 20-50 min.

5. A method for preparing an intumescent flame retardant and heat insulating multi-layer coating as claimed in any one of claims 1 to 4, characterized in that: The preparation method of the first coating layer includes: Adding 30-50 parts of water, 0.1-1 parts of hydroxyethyl cellulose, 0.3-3 parts of ethylene glycol, 0.1-1 parts of silicone defoamer and 0.1-0.5 parts of anti-flash rust agent to 5-15 parts of aqueous styrene acrylic emulsion by mass to obtain a first mixed solution; 5-15 parts of the composite expandable heat-insulating filler and 1-4 parts of alcohol ester dodecahydrate are added to the first mixed solution to obtain the first layer of coating.

6. The method for preparing the intumescent flame retardant and heat insulating multi-layer coating according to claim 5, characterized in that: The preparation method of the second coating layer includes: Mix 10 parts of aqueous styrene acrylic emulsion, 8 parts of water and 0.5 parts of organosilicon defoamer by mass to obtain a second mixed solution; Adding 5 parts of melamine-coated ammonium polyphosphate, 3 parts of melamine, 3 parts of pentaerythritol, 0.5 parts of titanium dioxide, and 0.5 parts of expandable graphite to the second mixed solution, and stirring to obtain a third mixed solution; 0.1 parts of a thickener is added to the third mixed solution to obtain the second coating layer.

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