Preparation method of light-weight high-strength thermal insulation material

Abstract

The application discloses a preparation method of a light high-strength thermal insulation material, and has the characteristics that the method comprises the following steps: preparing inorganic fibers; pretreating the inorganic fibers to obtain primary inorganic fibers; uniformly mixing ceramic powder, a first binder and a second binder with a solidifying agent to obtain mixed powder; the first binder and the second binder with the solidifying agent are solid powders; preparing a reinforcing additive solution, dipping the primary inorganic fibers in the reinforcing additive solution to obtain secondary inorganic fibers; dipping the secondary inorganic fibers in a second binder solution to obtain tertiary inorganic fibers; uniformly mixing the tertiary inorganic fibers with the mixed powder to obtain forming raw materials; forming the forming raw materials through a mold to obtain a ceramic body, and the ceramic body is left to solidify, demolded and the light high-strength thermal insulation material is obtained; the thermal insulation material prepared without sintering has high strength and light weight in use, and problems such as powder dropping and cracking are avoided.

Description

TECHNICAL FIELD

[0001] The present application relates to the field of heat insulation material preparation, in particular to a preparation method of light high-strength heat insulation material. BACKGROUND

[0002] The heat insulation materials in the cement and other industrial sintering systems are mostly nano heat insulation plates, which are mainly made of nano or micron-sized silicon dioxide, inorganic fibers and other small amount of additives by sintering or directly molded without sintering.

[0003] The heat insulation material directly molded without sintering has low strength, and has serious problems such as powder falling and cracking during use, which affects the heat insulation effect; and the heat insulation material prepared by sintering has a complex preparation process and high cost.

[0004] Therefore, how to omit the sintering process while ensuring that the prepared heat insulation material has high strength and does not fall powder and crack during use has become a technical problem to be solved in the field. SUMMARY

[0005] In order to solve the above technical problems, the present application provides a preparation method of light high-strength heat insulation material, which realizes high strength and light weight of the heat insulation material prepared without sintering in use, and avoids problems such as powder falling and cracking.

[0006] According to one aspect of the present application, a preparation method of light high-strength heat insulation material is provided, comprising the following steps: preparing inorganic fibers; pretreating the inorganic fibers to obtain primary inorganic fibers;

[0007] Mixing the ceramic powder, the first binder and the second binder with a curing agent uniformly to obtain a mixed powder;

[0008] The first binder and the second binder curing agent are solid powders;

[0009] Configuring a reinforcing additive solution, and immersing the primary inorganic fibers in the reinforcing additive solution to obtain secondary inorganic fibers;

[0010] Immersing the secondary inorganic fibers in a second binder solution to obtain tertiary inorganic fibers;

[0011] Mixing the tertiary inorganic fibers and the mixed powder uniformly to obtain a molding raw material;

[0012] Forming the molding raw material through a mold to obtain a ceramic body, and then standing, curing, demolding and obtaining the light high-strength heat insulation material.

[0013] Compared with the prior art, the application has the following beneficial effects: by pretreating the inorganic fibers to obtain primary inorganic fibers and then dipping the primary inorganic fibers in a reinforcing aid solution to obtain secondary inorganic fibers, the modifier on the surface of the inorganic fibers in the finished thermal insulation material is chemically reacted with the reinforcing aid in the high temperature during use, so that the strength of the joint between the inorganic fibers is further enhanced, thereby facilitating the continuous increase in the strength of the thermal insulation material during use; meanwhile, the increase of the modifier and the reinforcing aid is realized by the surface modification of the inorganic fibers and the dipping of the primary fibers in the reinforcing aid, thereby avoiding the uneven combination of the modifier and the reinforcing aid in the thermal insulation material, avoiding the problem that the unreacted modifier and the reinforcing aid are dispersed between the inorganic fibers, and avoiding the reduction of the porosity and the thermal insulation performance of the thermal insulation material.

[0014] By mixing the ceramic powder with the first binder, the strength of the finished thermal insulation material is further significantly improved when the ambient temperature is within 100 DEG C during use, and the cracking problem does not occur during use, and meanwhile, the uniform pores are further generated with the increase of the temperature, thereby facilitating the improvement of the finished thermal insulation performance and the further reduction of the weight.

[0015] By uniformly mixing the ceramic powder with the second binder and the curing agent and dipping the secondary inorganic fibers in the second binder solution to obtain tertiary inorganic fibers, the bonding strength between the ceramic powder and the inorganic fibers is improved, and the strength of the obtained thermal insulation material is high at room temperature during non-use; and when the ambient temperature gradually increases to about 200 DEG C during use, the second binder solution is beneficial to further improving the porosity and the strength of the thermal insulation material, and the strength of the solid substances in the second binder solution gradually increases with the increase of the temperature, thereby further improving the strength of the thermal insulation material.

[0016] By the above scheme, the reinforcing aid is located between the modifier on the surface of the inorganic fibers and the solid substances in the second binder solution, and most of the reinforcing aid is combined with the modifier to be ceramicized, and a small part of the reinforcing aid is combined with the solid substances in the second binder solution to further improve the strength between the inorganic fibers and the ceramic powder.

[0017] Therefore, the finished thermal insulation material finally obtained has high strength before use, and the strength gradually increases with the increase of the temperature during use, the strength of the finished thermal insulation material gradually increases at different temperature stages, thereby avoiding the problems such as falling off and cracking of the finished product during use; meanwhile, the finished product has high porosity and good thermal insulation performance and light weight, and the porosity gradually increases during use, the thermal insulation performance is further improved, and the weight is further reduced.

[0018] Further, the first binder is a paraffin powder; and / or

[0019] The second binder curing agent includes one or more of sodium fluorosilicate, silicon phosphate, aluminum tripolyphosphate, and magnesium oxide.

[0020] The first binder is paraffin powder, which is a solid powder or particle, and is beneficial to uniform mixing with the ceramic powder. When the primary environment temperature is within 100℃, the paraffin viscosity further increases, the product strength is further significantly enhanced, and the product cracking and slagging problems are avoided. When the temperature further increases, the paraffin gasifies, and the porosity increases.

[0021] The second binder curing agent includes one or more of sodium fluorosilicate, silicon phosphate, aluminum tripolyphosphate, and magnesium oxide, which is beneficial to achieving high strength of the product at room temperature without heating after demolding.

[0022] Further, the second binder solution includes an inorganic binder solution and a room-temperature curing binder.

[0023] The mass ratio of the inorganic binder solution to the room-temperature curing binder is (1.5-3.5):1.

[0024] And / or

[0025] The mass ratio of the inorganic fiber, the first binder, the second binder solution, and the second binder curing agent is 1:(0.1-0.75):(0.25-1.35):(2.5x10 -4 -6x10 -3 ).

[0026] The second binder solution includes an inorganic binder solution and a room-temperature curing binder, which achieves high bonding strength of the ceramic powder and the inorganic fiber at room temperature through the room-temperature curing binder. At the same time, the inorganic fiber and the ceramic powder have high bonding strength at room temperature, and the inorganic binder is beneficial to further increasing the strength and further increasing the porosity and further reducing the weight during use.

[0027] Through the material ratio, the product has high strength at room temperature without use, and the strength gradually increases, the porosity further increases, and the product cracking or strength reduction problems caused by the increase in porosity are avoided.

[0028] Further, the inorganic binder solution includes a silicate aqueous solution and a phosphate aqueous solution.

[0029] The mass fraction of silicate in the silicate aqueous solution is 30-40%, and the mass fraction of phosphate in the phosphate aqueous solution is 30-40%.

[0030] The silicate is one or more of sodium silicate, potassium silicate, calcium silicate;

[0031] The phosphate is aluminum phosphate and / or dihydrogen aluminum phosphate.

[0032] The beneficial effect of the above step is that, by using inorganic binder including aqueous silicate solution and aqueous phosphate solution, the inorganic fiber and ceramic powder can be bonded at room temperature, and the strength can be further increased with the increase of temperature during use, and the porosity of the product can be gradually increased during the process.

[0033] Further, the room temperature curing binder includes modified silicone resin, curing agent, film forming aid;

[0034] The modified silicone resin includes one or more of phenolic, alkyd, polyester, acrylic, epoxy, and polyurethane modified silicone resin;

[0035] The curing agent includes silane coupling agent or polyamide or polyurethane; the silane coupling agent includes one or more of propyltrimethoxysilane, aminopropyltrimethoxysilane, and propylmethyldimethoxysilane;

[0036] The film forming aid includes one or more of dipropylene glycol, diethylene glycol butyl ether, and butyl ether glycol butyl ether;

[0037] The mass ratio of the modified silicone resin, curing agent, and film forming aid is 1:(0.3-1):(0-0.5).

[0038] The beneficial effect of the above step is that, the second binder solution can be uniformly dispersed, and the ceramic powder and inorganic fiber can be bonded at room temperature with high strength.

[0039] Further, the specific process for pretreating the inorganic fiber to obtain the primary inorganic fiber is as follows:

[0040] The primary inorganic fiber is immersed in silica sol and dried to obtain the primary inorganic fiber with silica sol attached to the surface.

[0041] The mass ratio of the inorganic fiber and the silica sol attached to the surface of the inorganic fiber is 1:(0.02-0.1).

[0042] Further, the specific process for configuring the reinforcing aid solution is as follows: the reinforcing aid is mixed with water or ethanol to obtain the reinforcing aid solution, and the reinforcing aid is boron nitride and / or boron carbide;

[0043] The mass ratio of the inorganic fiber and the reinforcing aid is 1:(0.05-0.2).

[0044] The beneficial effect of the above step is that by impregnating the surface of the inorganic fiber with the silica sol, the silica sol on the surface of the inorganic fiber in the finished product reacts with the reinforcing aid during use, that is, it is beneficial to increase the strength of the inorganic fiber itself, mainly to further increase the strength of the inorganic fiber intersection point by the reaction of the silica sol and the reinforcing aid to form borosilicate compounds, and significantly improve the strength of the finished product, while avoiding the problem of reducing porosity caused by filling the silica sol in the pores between the inorganic fibers.

[0045] Further, the inorganic fiber includes one or more of alkali-free glass fiber, aluminum silicate fiber, aluminum oxide fiber, mullite fiber, high-silica fiber, and basalt fiber.

[0046] The diameter of the inorganic fiber is 3-9 microns, and the length is 1-10 mm.

[0047] And / or

[0048] The ceramic powder includes microsilica powder and infrared radiation agent.

[0049] The ceramic powder is microsilica powder, the content of SiO2 in the microsilica powder is ≥90%, the average particle size is 0.1-0.15 microns, the specific surface area is 15-27 m 2 / g, and the bulk density is 250-300 kg / m 3 .

[0050] The infrared radiation agent is silicon carbide or titanium dioxide.

[0051] Further, the mass ratio of the inorganic fiber, the microsilica powder, and the infrared radiation agent is (45-94%):(5-20%):(1-5%).

[0052] Further, the ceramic body is impregnated again after solidification, and then solidified and demolded to obtain the lightweight high-strength thermal insulation material.

[0053] Specific process: the second binder solution is mixed with the second binder curing agent and impregnated on the surface of the ceramic body.

[0054] The beneficial effect of the above step is that it is beneficial to further improve the strength of the finished product at room temperature without use. DETAILED DESCRIPTION

[0055] In order to better understand the technical solutions of the present application, the present application will be further described below in combination with specific embodiments and the accompanying drawings.

[0056] Example 1

[0057] According to the present embodiment, a preparation method of a lightweight high-strength thermal insulation material is provided, including the following steps: preparing inorganic fiber;

[0058] The specific process of pre-treating the inorganic fiber to obtain the primary inorganic fiber is: dipping the primary inorganic fiber in a silica sol, drying to obtain the primary inorganic fiber, and the surface of the primary inorganic fiber is attached with the silica sol; and the mass ratio of the inorganic fiber to the silica sol attached to the surface of the inorganic fiber is 1:0.06.

[0059] The inorganic fiber includes alkali-free glass fiber, aluminum silicate fiber, and aluminum oxide fiber; the diameter of the inorganic fiber is 6-7 μm, and the length is 5-6 mm;

[0060] The reinforcing additive solution is prepared, and the primary inorganic fiber is dipped in the reinforcing additive solution to obtain the secondary inorganic fiber; the specific process of preparing the reinforcing additive solution is: mixing the reinforcing additive with ethanol to obtain the reinforcing additive solution, and the reinforcing additive is boron nitride; and the mass ratio of the inorganic fiber to the reinforcing additive is 0.125:1.

[0061] The second binder solution is prepared, and the surface of the secondary inorganic fiber is dipped in the second binder solution to obtain the tertiary inorganic fiber; the second binder solution includes an inorganic binder solution and a normal-temperature curing binder; the mass ratio of the inorganic binder solution to the normal-temperature curing binder is 2.5:1; and the mass ratio of the inorganic fiber, the first binder, the second binder solution, and the curing agent for the second binder is 1:0.43:0.8:3.2x10 -3 ;

[0062] The inorganic binder solution includes a silicate aqueous solution and a phosphate aqueous solution; the mass fraction of the silicate in the silicate aqueous solution is 35%, and the mass fraction of the phosphate in the phosphate aqueous solution is 35%;

[0063] The silicate is sodium silicate or potassium silicate; and the phosphate is aluminum phosphate and dihydrogen aluminum phosphate;

[0064] The normal-temperature curing binder includes modified silicone resin, a curing agent, and a film-forming aid;

[0065] The modified silicone resin includes phenolic, alkyd, polyester, and acrylic modified silicone resin; the curing agent includes a silane coupling agent; the silane coupling agent is propyl trimethoxysilane; and the film-forming aid includes dipropylene glycol and diethylene glycol butyl ether;

[0066] The mass ratio of the modified silicone resin, the curing agent, and the film-forming aid is 1:0.65:0.25.

[0067] The ceramic powder is uniformly mixed with the first binder and the curing agent for the second binder to obtain a mixed powder; the first binder and the curing agent for the second binder are solid powders;

[0068] Mixing the three-stage inorganic fiber with the mixed powder to obtain a molding raw material;

[0069] Molding the molding raw material through a mold to obtain a ceramic body, standing for curing, demolding to obtain the light high-strength thermal insulation material.

[0070] The first binder is paraffin powder; the ceramic powder comprises micro-silicon powder and infrared radiation agent; the infrared radiation agent is silicon carbide;

[0071] The second binder uses a curing agent comprising one or more of sodium fluorosilicate, silicon phosphate, aluminum tripolyphosphate and magnesium oxide;

[0072] The SiO2 content in the micro-silicon powder is ≥ 90%, the average particle size is 0.12 μm, the specific surface area is 22 m 2 / g, and the bulk density is 280 kg / m 3 ; the mass ratio of the inorganic fiber, micro-silicon powder and infrared radiation agent is 75%:12.5%:3%.

[0073] Example Two

[0074] The same content as in Example One is not repeated here; this example provides a preparation method of a light high-strength thermal insulation material;

[0075] The mass ratio of the inorganic fiber and the silicon sol attached to the surface of the inorganic fiber is 1:0.04.

[0076] The inorganic fiber comprises one or more of aluminum silicate fiber, mullite fiber and basalt fiber; the diameter of the inorganic fiber is 3-4 μm, and the length is 2-3 mm;

[0077] The reinforcing aid is one or both of boron nitride and boron carbide; the mass ratio of the inorganic fiber and the reinforcing aid is 0.08:1.

[0078] The mass ratio of the inorganic binder solution and the room-temperature curing binder is 1.8:1; the mass ratio of the inorganic fiber, the first binder, the second binder solution, the second binder curing agent is 1:0.15:0.3:3.5x10 -4 ;

[0079] The silicate is sodium silicate or calcium silicate; the phosphate is aluminum phosphate

[0080] The modified silicone resin comprises polyester, acrylic, epoxy and polyurethane modified silicone resin; the curing agent comprises silicone polyamide; the film-forming aid comprises butyl ether glycol butyl ether;

[0081] The mass ratio of the modified silicone resin, the curing agent and the film-forming aid is 1:0.4:0.4.

[0082] The infrared radiation agent is silicon carbide or titanium dioxide;

[0083] The mass ratio of the inorganic fiber, micro-silicon powder, and infrared radiation agent is 50:8:2.

[0084] Example Three

[0085] The same content as in Example One is not repeated; this embodiment provides a preparation method of a lightweight high-strength thermal insulation material.

[0086] The mass ratio of the inorganic fiber and the silicon sol attached to the surface of the inorganic fiber is 1:0.08.

[0087] The inorganic fiber includes one or more of alkali-free glass fiber, aluminum silicate fiber, aluminum oxide fiber, mullite fiber, high-silica fiber, and basalt fiber; the inorganic fiber has a diameter of 7-8 μm and a length of 8-9 mm;

[0088] The reinforcing aid is boron carbide; the mass ratio of the inorganic fiber and the reinforcing aid is 0.18:1.

[0089] The mass ratio of the inorganic binder solution and the room-temperature curing binder is 3.2:1; the mass ratio of the inorganic fiber, the first binder, the second binder solution, the second binder, and the curing agent is 1:0.7:1.3:5x10 -3 ;

[0090] The silicate is calcium silicate; the phosphate is aluminum dihydrogen phosphate;

[0091] The modified silicone resin includes polyester, acrylic, and epoxy modified silicone resin; the curing agent includes polyurethane; the film-forming aid includes diethylene glycol butyl ether;

[0092] The mass ratio of the modified silicone resin, the curing agent, and the film-forming aid is 1:0.8:0.3.

[0093] The infrared radiation agent is titanium dioxide;

[0094] The mass ratio of the inorganic fiber, micro-silicon powder, and infrared radiation agent is 80:15:3.

[0095] The ceramic body is again impregnated after standing and curing, and then is cured and demolded to obtain the lightweight high-strength thermal insulation material; the specific process is that the second binder solution is mixed with the second binder curing agent and then is impregnated on the surface of the ceramic body.

[0096] The above description is only the preferred embodiment of the present application and the explanation of the technical principles. It should be understood by those skilled in the art that the scope of the application involved in the present application is not limited to the technical solutions formed by the specific combinations of the above technical features, and should also cover other technical solutions formed by the combinations of the above technical features or their equivalent features without departing from the inventive concept. For example, the above features are equivalent to the features disclosed in the present application (but not limited to) with similar functions.

Claims

1. A method for preparing a lightweight, high-strength thermal insulation material, characterized in that, Includes the following steps: Inorganic fibers are pretreated to obtain primary inorganic fibers. The specific process of pretreatment of inorganic fibers is as follows: the inorganic fibers are impregnated in silica sol and dried to obtain the primary inorganic fibers. The mass ratio of the inorganic fibers to the silica sol adhering to the surface of the inorganic fibers is 1:(0.02~0.1). The ceramic powder is mixed evenly with the first binder and the second binder curing agent to obtain a mixed powder, wherein the first binder and the second binder curing agent are solid powders; The specific process for preparing the reinforcing agent solution is as follows: mixing the reinforcing agent with water or ethanol to obtain the reinforcing agent solution, wherein the reinforcing agent is boron nitride and / or boron carbide; Primary inorganic fibers are impregnated in a reinforcing agent solution to obtain secondary inorganic fibers; the mass ratio of the inorganic fibers to the reinforcing agent is 1:(0.05~0.2). The surface of secondary inorganic fibers is impregnated with a second binder solution to obtain tertiary inorganic fibers; The tertiary inorganic fiber is mixed evenly with the mixed powder to obtain the molding raw material; The raw material is molded into a ceramic blank through a mold, allowed to stand and solidify, and then demolded to obtain the lightweight, high-strength thermal insulation material. The first adhesive is paraffin powder; The curing agent for the second adhesive includes one or more of sodium fluorosilicate, silicon phosphate, aluminum tripolyphosphate, and magnesium oxide; The second adhesive solution includes an inorganic adhesive solution and a room-temperature curing adhesive; The inorganic binder solution comprises an aqueous silicate solution and an aqueous phosphate solution; The room-temperature curing adhesive includes modified silicone resin, curing agent, and film-forming aid.

2. The method for preparing the lightweight, high-strength thermal insulation material according to claim 1, characterized in that, The mass ratio of the inorganic binder solution to the room-temperature curing binder is (1.5~3.5):1; and / or The mass ratio of the inorganic fiber, the first adhesive, the second adhesive solution, and the curing agent for the second adhesive is 1:(0.1~0.75):(0.25~1.35):(2.5×10⁻⁶). -4 ~6×10 -3 ).

3. The method for preparing the lightweight, high-strength thermal insulation material according to claim 2, characterized in that, The silicate aqueous solution contains 30-40% silicate by mass, and the phosphate aqueous solution contains 30-40% phosphate by mass. The silicate is one or more of sodium silicate, potassium silicate, and calcium silicate; The phosphate is aluminum phosphate and / or aluminum dihydrogen phosphate.

4. The method for preparing the lightweight, high-strength thermal insulation material according to claim 2, characterized in that, The modified silicone resin includes one or more of phenolic, alkyd, polyester, acrylic, epoxy, and polyurethane modified silicone resins. The curing agent includes a silane coupling agent, a polyamide, or a polyurethane; the silane coupling agent includes one or more of propyltrimethoxysilane, aminopropyltrimethoxysilane, and propylmethyldimethoxysilane. The film-forming aid includes one or two of dipropylene glycol and diethylene glycol butyl ether; The mass ratio of the modified silicone resin, curing agent, and film-forming aid is 1:(0.3~1):(0~0.5).

5. The method for preparing the lightweight, high-strength thermal insulation material according to claim 1, characterized in that, The inorganic fibers include one or more of the following: alkali-free glass fiber, aluminosilicate fiber, alumina fiber, mullite fiber, high-silica fiber, and basalt fiber. The inorganic fibers have a diameter of 3~9μm and a length of 1~10mm; and / or The ceramic powder includes microsilica powder and infrared radiant; The microsilica powder contains ≥90% SiO2, has an average particle size of 0.1~0.15μm, and a specific surface area of ​​15~27m². 2 / g, bulk density 250~300kg / m³ 3 ; The infrared radiant is silicon carbide or titanium dioxide.

6. The method for preparing the lightweight, high-strength thermal insulation material according to claim 5, characterized in that, The mass ratio of the inorganic fiber, microsilica powder, and infrared radiant is (45~94%): (5~20%): (1~5%).

7. The method for preparing the lightweight, high-strength thermal insulation material according to claim 1, characterized in that, After the ceramic blank is allowed to stand and solidify, it is impregnated again, then solidified and demolded to obtain the lightweight, high-strength thermal insulation material. Specific process: The second adhesive solution is mixed with the second adhesive and then impregnated onto the surface of the ceramic blank.