A soluble fiber inorganic ceramic plate and a method for manufacturing the same

Abstract

The application provides a soluble fiber inorganic ceramic plate and a preparation method thereof. The method comprises the following steps: S10: performing polysiloxane coating treatment on soluble ceramic fibers to obtain modified soluble ceramic fibers; wherein the polysiloxane comprises amino groups; S20: dispersing the modified soluble ceramic fibers in water to obtain a first mixed solution; S30: adding an epoxy silane coupling agent to a silica sol binder to graft an epoxy group on the surface of silica in the silica sol binder to obtain a second mixed solution; and S40: mixing the first mixed solution and the second mixed solution to obtain a slurry, performing wet vacuum forming on the slurry, and drying to obtain the soluble fiber inorganic ceramic plate. The soluble fiber inorganic ceramic plate prepared by the method has good moisture resistance and strength.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of fiber board, in particular to a soluble fiber inorganic ceramic board and a preparation method thereof. BACKGROUND

[0002] Traditional ceramic fiber products mainly contain Al2O3 and SiO2. The ceramic fiber with the components has fatal defects in the production and use of other thermal insulation materials. The diameter of the ceramic fiber is small, mostly less than 6 μm, and the ceramic fiber is brittle and easy to break, which produces fiber dust and is easily inhaled into the human body, thereby affecting human health. The soluble ceramic fiber is an alkaline earth silicate fiber mainly containing SiO2, MgO and CaO. Because it has a certain solubility in human body fluid, it reduces the damage to human health, shortens the residence time in the human body, does not cause damage to human health, and at least reduces the damage to human health to the minimum, so it is called soluble ceramic fiber. Therefore, the soluble fiber inorganic ceramic board made of soluble ceramic fiber is expected to replace conventional inorganic ceramic board in some fields, which is an important development direction in the field.

[0003] Compared with ceramic fiber, soluble ceramic fiber generally has a higher content of silicon dioxide and is generally a glass fiber. Compared with ceramic fiber, soluble ceramic fiber has stronger hygroscopicity, which may cause the soluble ceramic fiber to absorb moisture, weaken the adhesion between the soluble ceramic fiber and the binder, and dissolve the alkali metal oxides in the soluble ceramic fiber due to water, thereby reducing the strength of the soluble fiber inorganic ceramic board.

[0004] Patent CN118756526A discloses an inorganic soluble fiber board and a preparation method thereof. The method comprises the following steps: S10: dispersing inorganic soluble fiber, silica sol binder and unsaturated silane coupling agent in water to graft unsaturated carbon-carbon bonds on the surface of the inorganic soluble fiber and the silica sol to obtain a mixed solution; S20: adding an acrylamide monomer and a crosslinking agent to the mixed solution to flocculate by initiating a polymerization reaction to obtain a slurry; and S30: wet vacuum forming the slurry to obtain the inorganic soluble fiber board after drying. According to the present application, the inorganic soluble fiber board has good moisture resistance and strength.

[0005] The inorganic soluble fiber board described above grafts unsaturated carbon-carbon bonds on the inorganic soluble fiber and the silica sol, and crosslinks and polymerizes with the acrylamide monomer to obtain a uniform and dense inorganic soluble fiber board, which has good moisture resistance and reduces the diffusion of water into the fiber board. However, the acrylamide monomer has a certain hydrophilicity, and the moisture resistance needs to be further improved.

[0006] Therefore, it is necessary to provide a soluble fiber inorganic ceramic board with moisture resistance and high strength. SUMMARY

[0007] The present application provides a soluble fiber inorganic ceramic plate and a preparation method thereof, which has good moisture resistance and strength.

[0008] In a first aspect, the present application provides a method for preparing a soluble fiber inorganic ceramic plate, comprising the following steps:

[0009] S10: performing polysiloxane coating treatment on the soluble ceramic fiber to obtain modified soluble ceramic fiber; wherein the polysiloxane comprises an amino group;

[0010] S20: dispersing the modified soluble ceramic fiber in water to obtain a first mixed solution;

[0011] S30: adding an epoxy silane coupling agent to the silica sol binder to graft an epoxy group onto the surface of the silica in the silica sol binder to obtain a second mixed solution;

[0012] S40: mixing the first mixed solution and the second mixed solution to obtain a slurry, and performing wet vacuum forming on the slurry, and drying to obtain a soluble fiber inorganic ceramic plate.

[0013] According to the present application, by modifying the soluble ceramic fiber to be hydrophobic and coating polysiloxane on the surface of the soluble ceramic fiber, the moisture resistance of the soluble ceramic fiber can be improved, and the polysiloxane comprises an amino group, which can promote the flocculation and precipitation of the silica colloidal particles in the silica sol binder and the cross-linking reaction with the epoxy group on the surface of the silica colloidal particles in the subsequent drying process, so that the components in the soluble fiber inorganic ceramic plate are tightly combined without adding a hydrophilic organic binder, thereby effectively reducing the intrusion of water and improving the strength, and the obtained soluble fiber inorganic ceramic plate has good moisture resistance and strength.

[0014] In some embodiments, the soluble ceramic fiber is an inorganic alkaline earth silicate fiber, and the length of the soluble ceramic fiber is 0.1-10 mm.

[0015] In some embodiments, the step S10 comprises:

[0016] S11: adding the soluble ceramic fiber to an aqueous nitric acid solution for activation treatment to obtain activated soluble ceramic fiber;

[0017] S12: dissolving and dispersing the activated soluble ceramic fiber, a silane coupling agent and a catalyst in ethanol for polycondensation reaction to coat polysiloxane on the surface of the soluble ceramic fiber to obtain modified soluble ceramic fiber; wherein the silane coupling agent comprises an amino silane coupling agent with three functional groups.

[0018] In some embodiments, the S11 comprises: 10 parts by mass of the soluble ceramic fiber is dispersed in 50-500 parts by mass of 2wt%-6wt% nitric acid aqueous solution, and activated at 25-40℃ for 10-30min, and then filtered and dried to obtain the activated soluble ceramic fiber.

[0019] In some embodiments, the S12 comprises: 10 parts by mass of the activated soluble ceramic fiber, 10-30 parts by mass of the silane coupling agent, and 0.1-1 parts by mass of the catalyst are dissolved and dispersed in 300-700 parts by mass of ethanol, and then subjected to polycondensation reaction at 70-90℃ for 18-30h, and then filtered and dried to obtain the modified soluble ceramic fiber.

[0020] In some embodiments, in the step S12, the silane coupling agent further comprises a three-functionality fluorine-containing silane coupling agent, the polyoxysilane further comprises fluorine atoms, and the mass ratio of the three-functionality amino silane coupling agent to the three-functionality fluorine-containing silane coupling agent is 1:0.1-0.3.

[0021] In some embodiments, the step S20 specifically comprises: 10 parts by mass of the modified soluble ceramic fiber is dispersed in 50-200 parts by mass of water to obtain a first mixed solution.

[0022] In some embodiments, the step S30 specifically comprises: 0.2-1 parts by mass of the epoxy silane coupling agent is added to 1-5 parts by mass of the silica sol binder with a solid content of 20wt%-40wt%, and then subjected to stirring reaction at 30-60℃ for 1-4h to obtain a second mixed solution.

[0023] In some embodiments, in the step S40, the wet vacuum forming comprises: using vacuum filtration at a vacuum degree of 0.03-0.06MPa, and using roller pressing at a roller pressing pressure of 0.05-0.1MPa; and the drying condition comprises: drying at 100-150℃ for 5-12h.

[0024] In a second aspect, the present application provides a soluble fiber inorganic ceramic plate prepared by the method according to any one of the embodiments of the first aspect. DETAILED DESCRIPTION

[0025] Each embodiment in the specification is described in a progressive manner, and each embodiment focuses on the difference from other embodiments.

[0026] In the description of the present specification, the description referring to the terms "one embodiment", "some embodiments", "exemplary embodiment", "example", "specific example", or "some examples" and the like means that the particular feature, structure, material, or characteristic being described in connection with the embodiment or example contains in at least one embodiment or example of the present application. The exemplary expressions of the above terms in the present specification do not necessarily refer to the same embodiment or example. Also, the particular feature, structure, material, or characteristic being described can be combined in any one or more embodiments or examples with a suitable arrangement.

[0027] In addition, the terms "first", "second", are used only for descriptive purposes and should not be construed as indicating or implying relative importance or an indicated number of technical features. Thus, the features defined with "first", "second" can explicitly or implicitly include at least one of the features. In the description of the present application, the meaning of "a plurality of" is at least two, for example, two, three, etc., unless otherwise explicitly specified.

[0028] In order to further improve the moisture resistance and strength of the soluble fiber inorganic ceramic plate, the present application provides a soluble fiber inorganic ceramic plate and a preparation method thereof. The inventors can avoid the use of hydrophilic organic binder by hydrophobic modification of the surface of the soluble fiber inorganic ceramic plate and the coating layer containing amino groups, and can enhance the adhesion between the modified soluble ceramic fiber and the silica sol binder interface by grafting epoxy groups on the surface of the silica in the silica sol binder and cross-linking reaction of the epoxy groups and the amino groups. The soluble fiber inorganic ceramic plate obtained thereby has good moisture resistance and strength. The specific embodiments of the present application are described in detail below.

[0029] In a first aspect, the present application provides a method for preparing a soluble fiber inorganic ceramic plate, comprising the following steps:

[0030] S10: Polysiloxane coating treatment is performed on the soluble ceramic fiber to obtain modified soluble ceramic fiber; wherein the polysiloxane contains amino groups;

[0031] S20: The modified soluble ceramic fiber is dispersed in water to obtain a first mixed solution;

[0032] S30: Epoxy silane coupling agent is added to the silica sol binder to graft epoxy groups on the surface of the silica in the silica sol binder to obtain a second mixed solution;

[0033] S40: The first mixed solution and the second mixed solution are mixed to obtain a slurry, and the slurry is wet vacuum formed, dried to obtain a soluble fiber inorganic ceramic plate.

[0034] According to the present application, by hydrophobic modification of the soluble ceramic fiber, the surface of the soluble ceramic fiber is coated with polysiloxane, which can improve the moisture resistance of the soluble ceramic fiber, and the polysiloxane contains amino groups, which can promote the flocculation and precipitation of silica colloidal particles in the silica sol binder, and cross-linking reaction with the epoxy groups on the surface of the silica colloidal particles during subsequent drying process, so that the components in the soluble fiber inorganic ceramic plate are tightly combined without adding hydrophilic organic binder, thereby effectively reducing the intrusion of moisture and improving the strength, and the obtained soluble fiber inorganic ceramic plate has good moisture resistance and strength.

[0035] Specifically, in step S10, in order to reduce the influence of moisture on the soluble ceramic fiber and improve the moisture resistance of the soluble ceramic fiber, the present application coats the surface of the soluble ceramic fiber with polysiloxane, which has good hydrophobicity and can effectively reduce the intrusion of moisture to protect the soluble ceramic fiber; in addition, since the modified soluble ceramic fiber coated with polysiloxane will affect its adhesion performance with the silica sol binder, the polysiloxane contains amino groups, which can be flocculated and precipitated with the silica colloidal particles in the silica sol through electrostatic action on one hand, and can cross-link with the epoxy groups grafted on the surface of the silica colloidal particles in the silica sol on the other hand, thereby improving the interfacial adhesion between the modified soluble fiber and the silica sol binder, and the cross-linked structure can effectively reduce the penetration of moisture into the ceramic plate, while improving the strength of the soluble fiber inorganic ceramic plate.

[0036] In step S30, the silica colloidal particles in the silica sol binder are modified by using an epoxy silane coupling agent to graft epoxy groups on the surface of the silica colloidal particles, which have good reactivity with the amino groups on the surface of the modified soluble ceramic fiber, and the epoxy groups can cross-link with the amino groups to tightly bond the modified soluble ceramic fiber and the silica sol binder, thereby overcoming the influence of hydrophobic coating on the adhesion performance of the soluble ceramic fiber and the silica sol binder; it can be understood that the polysiloxane coated on the surface of the soluble ceramic fiber is a flexible material, and the ether amine bond obtained by the reaction of the epoxy groups and the amino groups is a flexible segment, and the two can effectively disperse the stress in the soluble fiber inorganic ceramic plate, thereby improving the strength of the soluble fiber inorganic ceramic plate.

[0037] In step S40, the first mixed solution and the second mixed solution are mixed to obtain a slurry, and the modified soluble ceramic fibers and the epoxy group grafted silica sol binder in the slurry are flocculated and settled by electrostatic action, and are formed by a wet vacuum forming process, which is beneficial to improve the density of the wet blank after forming, thereby improving the density of the soluble fiber inorganic ceramic plate, and the soluble fiber inorganic ceramic plate has good moisture resistance and strength; during the subsequent drying process, the amino group on the surface of the modified soluble ceramic fiber and the epoxy group on the surface of the silicon dioxide in the silica sol occur crosslinking reaction, the interfacial adhesion of the surface of the modified soluble ceramic fiber and the silica sol binder is improved, and the moisture resistance and strength of the soluble fiber inorganic ceramic plate are improved.

[0038] In some embodiments, the soluble ceramic fiber is an inorganic alkaline earth silicate fiber, and the length of the soluble ceramic fiber is 0.1-10 mm.

[0039] In some embodiments, the soluble ceramic fiber is an inorganic alkaline earth silicate fiber with SiO2, MgO and CaO as main components, which has strong in-vitro solubility, and the use of the above fiber can make the soluble ceramic fiber have better biological safety. For example, the soluble ceramic fiber used in the present application is selected from the soluble ceramic fiber purchased from Suzhou Gao Wei Thermal Energy Technology Co., Ltd. Soluble fiber cotton.

[0040] In some embodiments, step S10 comprises:

[0041] S11: adding the soluble ceramic fiber into an aqueous nitric acid solution for activation treatment to obtain activated soluble ceramic fiber;

[0042] S12: dissolving and dispersing the activated soluble ceramic fiber, a silane coupling agent and a catalyst in ethanol for polycondensation reaction to coat polysiloxane on the surface of the soluble ceramic fiber to obtain modified soluble ceramic fiber; wherein the silane coupling agent comprises three functional amino silane coupling agents.

[0043] In some embodiments, the method for coating polysiloxane on the soluble ceramic fiber is specifically limited. The soluble ceramic fiber is activated in an aqueous nitric acid solution to remove impurities on the surface of the soluble fiber and activate the hydroxyl groups on the surface, so that the silane coupling agent is more easily polymerized and coated to form polysiloxane on the surface. The three functional amino silane coupling agents have better reactivity, improve the crosslinking density of the polysiloxane, thereby improving the protection of the soluble ceramic fiber and further improving the moisture resistance of the soluble fiber inorganic ceramic plate; at the same time, the amino group on the surface of the polysiloxane obtained by polymerization of the amino silane coupling agent provides a reaction site for the epoxy group.

[0044] It can be understood that the three-functional amino silane coupling agent has the meaning known in the art, the three functionalities refer to the three siloxy groups that can be hydrolyzed in the amino silane coupling agent, and the amino silane coupling agent refers to a silane coupling agent containing an amino group; as an example, the three-functional amino silane coupling agent can be 3-aminopropyl triethoxysilane.

[0045] In some embodiments, S11 comprises: 10 parts by mass of soluble ceramic fibers are dispersed in 50-500 parts by mass of a 2wt%-6wt% nitric acid aqueous solution, activated at 25-40°C for 10-30 min, filtered and dried to obtain activated soluble ceramic fibers.

[0046] In the above embodiments, under the above conditions, the impurities on the surface of the soluble ceramic fibers can be effectively removed, the activity of the hydroxyl groups on the surface of the soluble ceramic fibers is improved, the silane coupling agent is promoted to polymerize and coat on the surface thereof, and the modified soluble ceramic fibers with good hydrophobicity are obtained, thereby improving the moisture resistance of the soluble fiber inorganic ceramic plate.

[0047] In some embodiments, S12 comprises: 10 parts by mass of activated soluble ceramic fibers, 10-30 parts by mass of a silane coupling agent, and 0.1-1 parts by mass of a catalyst are dissolved and dispersed in 300-700 parts by mass of ethanol, and polycondensation reaction is carried out at 70-90°C for 18-30 h, and then filtered and dried to obtain modified soluble ceramic fibers.

[0048] In the above embodiments, under the above conditions, the polysiloxane can be completely coated on the surface of the soluble ceramic fibers, and the modified soluble ceramic fibers with good properties are obtained, thereby improving the moisture resistance of the soluble fiber inorganic ceramic plate.

[0049] It can be understood that the catalyst can be selected from the catalysts known in the art that can catalyze the polymerization of the silane coupling agent, and as an example, the catalyst can be dibutyltin dilaurate.

[0050] In some embodiments, in step S12, the silane coupling agent further comprises a three-functional fluorine-containing silane coupling agent, the polyoxy silane further comprises a fluorine atom, and the mass ratio of the three-functional amino silane coupling agent to the three-functional fluorine-containing silane coupling agent is 1:0.1-0.3.

[0051] In some of the above embodiments, the silane coupling agent further comprises a fluorine-containing silane coupling agent with three functional groups, and the polysiloxane modifying the surface of the soluble ceramic fiber further comprises a fluorine atom, and the mass ratio of the amino silane coupling agent with one functional group and the fluorine-containing silane coupling agent with three functional groups in the silane coupling agent is controlled within the above range. On the one hand, the amino group on the surface of the modified soluble ceramic fiber is electrostatically combined with the silica flocculation in the silica sol, but as the drying process proceeds, the electrostatic force weakens, which causes the silica flocculation in the silica sol binder to float up, resulting in uneven distribution of the silica flocculation in the soluble fiber inorganic ceramic plate, affecting the moisture resistance and strength of the soluble fiber inorganic ceramic plate. The strong force between the fluorine atom on the surface of the soluble ceramic fiber and the silica flocculation can limit the floating of the silica flocculation during the drying process when the electrostatic force weakens, so that the silica flocculation is more evenly distributed, further improving the moisture resistance and strength of the soluble fiber inorganic ceramic plate. On the other hand, the fluorine atom on the surface of the polysiloxane can reduce the surface energy of the modified soluble ceramic fiber, further reducing the penetration of water into the fiber, thereby further improving the moisture resistance of the soluble fiber inorganic ceramic plate.

[0052] It can be understood that the fluorine-containing silane coupling agent with three functional groups has the meaning known in the art, and the three functional groups refer to three siloxyl groups in the fluorine-containing silane coupling agent that can undergo hydrolysis. The fluorine-containing silane coupling agent refers to a silane coupling agent containing a fluorine atom. As an example, the fluorine-containing silane coupling agent with three functional groups can be (3,3,3,-trifluoropropyl)trimethoxysilane.

[0053] In some embodiments, step S20 specifically comprises dispersing 10 parts by mass of the modified soluble ceramic fiber in 50-200 parts by mass of water to obtain a first mixture.

[0054] In some embodiments, step S30 specifically comprises adding 0.2-1 parts by mass of an epoxy silane coupling agent to 1-5 parts by mass of a silica sol binder with a solid content of 20wt%-40wt%, and stirring and reacting at 30-60°C for 1-4h to obtain a second mixture. Based on the above embodiments, the conditions for using the epoxy silane coupling agent to modify the silica sol binder are specifically defined. Under these conditions, the silica flocculation in the silica sol binder can be grafted with an epoxy group. It can be understood that the silica sol binder is a silica sol dispersed in water. As an example, the silica sol used in this application has a solid content of 30wt% and a particle size of 10-15nm. The epoxy silane coupling agent has the meaning known in the art, and the epoxy silane coupling agent is a silane coupling agent containing an epoxy group. As an example, the epoxy silane coupling agent can be γ-glycidoxypropyltrimethoxysilane.

[0055] In some embodiments, in step S40, the wet vacuum forming comprises: using a vacuum degree of 0.03-0.06 MPa for suction filtration, and using a pressure roller to roll, with a roller pressure of 0.05-0.1 MPa; and the drying conditions comprise: drying at 100-150°C for 5-12 h. Based on the above embodiments, vacuum suction filtration and pressure roller rolling are performed under the above conditions, which can further improve the density of the ceramic fiber board, and drying under the above conditions is conducive to crosslinking of the amino groups on the surface of the modified soluble ceramic fiber with the epoxy groups on the surface of the silica colloidal particles in the silica sol binder; thereby further improving the heat resistance and strength of the calcined-free ceramic fiber board.

[0056] In a second aspect, the present application provides a soluble fiber inorganic ceramic board prepared according to the method of any one of the embodiments of the first aspect.

[0057] According to the present application, since the soluble fiber inorganic ceramic board is prepared according to the method of any one of the embodiments of the first aspect, it has the beneficial effects of the first aspect.

[0058] Hereinafter, the embodiments of the present application will be described. The embodiments described below are exemplary and are only used to explain the present application, and cannot be understood as a limitation of the present application. If a specific technology or condition is not specified in the embodiments, it is performed according to the technology or condition described in the literature in the art or according to the product instruction. If the reagent or instrument used is not specified by the manufacturer, it is a conventional product that can be obtained by purchase.

[0059] Soluble ceramic fiber: the raw material is purchased from Suzhou Gao Wei Thermal Energy Technology Co., Ltd. Soluble fiber cotton, the soluble fiber cotton is dispersed in water, and a ceramic fiber chopper is used for chopping, and a filter screen with a mesh size of 5 mm is used for screening and washing to obtain the soluble ceramic fiber for standby.

[0060] Silica sol is purchased from Shandong Baiter New Material Co., Ltd., the model is SS3015, the particle size is 10-15 nm, and the mass content of silicon dioxide is 30%±1%.

[0061] Example 1

[0062] Preparation of the soluble fiber inorganic ceramic board:

[0063] 300 g of soluble ceramic fiber is dispersed in 5000 g of 5 wt% nitric acid aqueous solution, and activated at 35°C for 15 min, and then filtered and dried to obtain activated soluble ceramic fiber;

[0064] The activated soluble ceramic fiber, 500 g of 3-aminopropyl triethoxysilane, 100 g of (3,3,3,-trifluoropropyl) trimethoxysilane and 10 g of dibutyl tin dilaurate were dissolved and dispersed in 12 kg of ethanol, and the reaction was stirred at 85°C for 24 h, and then filtered and dried to obtain the modified soluble ceramic fiber;

[0065] The modified soluble ceramic fiber was dispersed in 3000 g of water to obtain a first mixed solution;

[0066] 18 g of γ-glycidoxypropyltrimethoxysilane was added to 90 g of 30 wt% silica sol binder, and the reaction was stirred at 50°C for 2 h to obtain a second mixed solution.

[0067] The first mixed solution and the second mixed solution were mixed to obtain a slurry, vacuum filtration was performed at a vacuum degree of 0.05 MPa, and roll pressing was performed at a roll pressing pressure of 0.05 MPa, and then wet blank pressing was performed to obtain a wet blank, and then drying was performed at 115°C for 8 h to obtain a soluble fiber inorganic ceramic plate.

[0068] Example 2

[0069] Preparation of a soluble fiber inorganic ceramic plate:

[0070] 300 g of soluble ceramic fiber was dispersed in 5000 g of 5 wt% nitric acid aqueous solution, and the reaction was activated at 35°C for 15 min, and then filtered and dried to obtain activated soluble ceramic fiber;

[0071] The activated soluble ceramic fiber, 600 g of 3-aminopropyl triethoxysilane and 10 g of dibutyl tin dilaurate were dissolved and dispersed in 12 kg of ethanol, and the reaction was stirred at 85°C for 24 h, and then filtered and dried to obtain the modified soluble ceramic fiber;

[0072] The modified soluble ceramic fiber was dispersed in 3000 g of water to obtain a first mixed solution;

[0073] 18 g of γ-glycidoxypropyltrimethoxysilane was added to 90 g of 30 wt% silica sol binder, and the reaction was stirred at 50°C for 2 h to obtain a second mixed solution.

[0074] The first mixed solution and the second mixed solution were mixed to obtain a slurry, vacuum filtration was performed at a vacuum degree of 0.05 MPa, and roll pressing was performed at a roll pressing pressure of 0.05 MPa, and then wet blank pressing was performed to obtain a wet blank, and then drying was performed at 115°C for 8 h to obtain a soluble fiber inorganic ceramic plate.

[0075] Example 3

[0076] Preparation of a soluble fiber inorganic ceramic plate:

[0077] 300g soluble ceramic fibers were dispersed in 5000g 5wt% nitric acid aqueous solution, and activated at 35°C for 15min, and then filtered and dried to obtain activated soluble ceramic fibers;

[0078] The activated soluble ceramic fibers, 300g 3-aminopropyltriethoxysilane, 300g (3,3,3,-trifluoropropyl)trimethoxysilane and 10g dibutyltin dilaurate were dissolved and dispersed in 12kg ethanol, and stirred and reacted at 85°C for 24h, and then filtered and dried to obtain modified soluble ceramic fibers;

[0079] The modified soluble ceramic fibers were dispersed in 3000g water to obtain a first mixed solution;

[0080] 18g γ-glycidoxypropyltrimethoxysilane was added to 90g 30wt% silica sol binder, and stirred and reacted at 50°C for 2h to obtain a second mixed solution.

[0081] The first mixed solution and the second mixed solution were mixed to obtain a slurry, vacuum filtration was performed at a vacuum degree of 0.05MPa, and a compression roller was used for rolling, the rolling pressure was 0.05MPa, and then wet blank was pressed, and then dried at 115°C for 8h to obtain a soluble fiber inorganic ceramic plate.

[0082] Comparative Example 1

[0083] Preparation of a soluble fiber inorganic ceramic plate:

[0084] 300g soluble ceramic fibers were dispersed in 3000g water, and then 90g 30wt% silica sol binder was added after uniform dispersion to obtain a mixed solution; and then 20g polyacrylamide was added, and flocculation and precipitation were performed to obtain a slurry.

[0085] Vacuum filtration was performed at a vacuum degree of 0.05MPa, and a compression roller was used for rolling, the rolling pressure was 0.05MPa, and then wet blank was pressed, and then dried at 115°C for 8h to obtain a soluble fiber inorganic ceramic plate.

[0086] Comparative Example 2

[0087] Preparation of a soluble fiber inorganic ceramic plate:

[0088] 300g soluble ceramic fibers were dispersed in 5000g 5wt% nitric acid aqueous solution, and activated at 35°C for 15min, and then filtered and dried to obtain activated soluble ceramic fibers;

[0089] The activated soluble ceramic fibers, 600g 3-aminopropyltriethoxysilane and 10g dibutyltin dilaurate were dissolved and dispersed in 12kg ethanol, and stirred and reacted at 85°C for 24h, and then filtered and dried to obtain modified soluble ceramic fibers;

[0090] The modified soluble ceramic fibers were dispersed in 3000 g of water to obtain a first mixture;

[0091] To the first mixture, 90 g of 30 wt% silica sol binder was added to obtain a mixture; 20 g of polyacrylamide was further added to the mixture to obtain a slurry, which was filtered under vacuum at a vacuum degree of 0.05 MPa, and then rolled at a pressure of 0.05 MPa to obtain a wet body, which was dried at 115 °C for 8 h to obtain a soluble fiber inorganic ceramic plate.

[0092] The soluble fiber inorganic ceramic plates obtained in Examples 1-3 and Comparative Examples 1 and 2 were tested for their bending strength according to GB / T 3001-2017, and the bending strength of the plates was tested again after the plates were placed in an incubator at a temperature of 80 °C and a relative humidity of 100% for 72 h. The difference in strength before and after incubation was calculated, and the results are shown in Table 1.

[0093] Table 1

[0094]

[0095] According to Table 1, the soluble fiber inorganic ceramic plates obtained in the examples of the present application have better moisture resistance and strength than the plates obtained in the comparative examples, which indicates that the soluble fiber inorganic ceramic plates obtained by the method of the present application have good moisture resistance and strength. It should be noted that, in order to verify the moisture resistance of the soluble fiber inorganic ceramic plates of the present application, accelerated moisture absorption simulation was performed in an oven at a high temperature and high humidity, and the difference in strength before and after incubation was calculated to evaluate the moisture resistance of the soluble fiber inorganic ceramic plates. The soluble fiber inorganic ceramic plate obtained in Comparative Example 1 has the worst moisture resistance, which may be due to its strong moisture absorption, which reduces the interfacial adhesion between the soluble ceramic fibers and the silica sol binder, and also reduces the strength of the soluble ceramic fibers themselves, resulting in poor moisture resistance. The soluble fiber inorganic ceramic plate obtained in Comparative Example 2 has the lowest strength before incubation, which may be due to the poor interfacial adhesion between the hydrophobically modified soluble ceramic fibers and the silica sol binder, resulting in poor adhesion of the components and low strength, and water is more easily penetrated into the plate, resulting in poor moisture resistance. However, its moisture resistance is better than that of Comparative Example 1, which may be due to the fact that the influence of water on the soluble ceramic fibers is smaller due to the coating, and the moisture resistance is improved compared to Comparative Example 1.

[0096] According to examples 1-3, the soluble fiber inorganic ceramic plate obtained in example 1 has the highest moisture resistance and strength, which can be due to the fact that the polysiloxane coated on the surface of the soluble ceramic fiber in example 2 only contains amino groups, which can cause uneven distribution of the silica sol binder during the drying process, resulting in lower strength and moisture resistance than example 1; although the polysiloxane coated on the surface of the soluble ceramic fiber in example 3 contains both amino groups and fluorine atoms, the relative content of amino groups is lower, and the crosslinking density is lower than that of examples 1 and 2, resulting in lower strength than examples 1 and 2, but more fluorine atoms are beneficial to reduce the penetration of water into the ceramic plate and the soluble ceramic fiber, so its moisture resistance is better than example 2; by controlling the appropriate ratio of amino groups and fluorine atoms on the polysiloxane coated on the surface of the soluble ceramic fiber in example 1, the silica sol binder can be uniformly distributed and the penetration of water can be reduced, so it has good strength and moisture resistance.

[0097] Finally, it should be noted that: the above examples are only used to illustrate the technical solutions of the present application, and not to limit them; although the present application has been described in detail with reference to the foregoing examples, those skilled in the art should understand that: it can still modify the technical solutions recorded in the foregoing examples, or make equivalent replacement for part or all of the technical features; and these modifications or replacements do not make the essence of the corresponding technical solutions deviate from the scope of the technical solutions of the embodiments of the present application.

Claims

1. A process for the preparation of soluble fiber inorganic ceramic boards, characterized by, The method comprises the following steps: S10: performing polysiloxane coating treatment on the soluble ceramic fiber to obtain modified soluble ceramic fiber; The polysiloxane comprises an amino group. S20: dispersing the modified soluble ceramic fiber in water to obtain a first mixed solution; S30: adding an epoxy silane coupling agent to the silica sol binder to graft an epoxy group on the surface of the silica in the silica sol binder to obtain a second mixed solution; S40: mixing the first mixed solution and the second mixed solution to obtain a slurry, and performing wet vacuum forming on the slurry, and drying to obtain a soluble fiber inorganic ceramic plate.

2. The method of claim 1, wherein, The soluble ceramic fiber is an inorganic alkaline earth silicate fiber, and the length of the soluble ceramic fiber is 0.1-10 mm.

3. The method of claim 1, wherein, The step S10 comprises: S11: adding the soluble ceramic fiber to an aqueous nitric acid solution for activation treatment to obtain activated soluble ceramic fiber; S12: dissolving and dispersing the activated soluble ceramic fiber, a silane coupling agent and a catalyst in ethanol for polycondensation reaction to coat the surface of the soluble ceramic fiber with polysiloxane to obtain modified soluble ceramic fiber; The silane coupling agent comprises a three-functionality amino silane coupling agent.

4. The method of claim 3, wherein, The S11 comprises: 10 parts by mass of the soluble ceramic fiber are dispersed in 50-500 parts by mass of an aqueous nitric acid solution with a concentration of 2wt%-6wt% for activation treatment at 25-40℃ for 10-30 min, and then filtered and dried to obtain the activated soluble ceramic fiber.

5. The method of claim 3, wherein, The S12 comprises: 10 parts by mass of the activated soluble ceramic fiber, 10-30 parts by mass of the silane coupling agent and 0.1-1 part by mass of the catalyst are dissolved and dispersed in 300-700 parts by mass of ethanol for polycondensation reaction at 70-90℃ for 18-30 h, and then filtered and dried to obtain the modified soluble ceramic fiber.

6. The method according to any one of claims 3 to 5, characterized in that, In the step S12, the silane coupling agent further comprises a three-functionality fluorine-containing silane coupling agent, the polysiloxane further comprises a fluorine atom, and the mass ratio of the three-functionality amino silane coupling agent to the three-functionality fluorine-containing silane coupling agent is 1:0.1-0.

3.

7. The method of claim 1, wherein, The step S20 specifically comprises: 10 parts by mass of the modified soluble ceramic fiber are dispersed in 50-200 parts by mass of water to obtain the first mixed solution.

8. The method of claim 7, wherein, The step S30 specifically comprises: 0.2-1 part by mass of the epoxy silane coupling agent is added to 1-5 parts by mass of the silica sol binder with a solid content of 20wt%-40wt% for stirring reaction at 30-60℃ for 1-4 h to obtain the second mixed solution.

9. The method of claim 1, wherein, In the step S40, The wet vacuum forming comprises: using a vacuum degree of 0.03-0.06 MPa for suction filtration, and using a press roller for rolling with a rolling pressure of 0.05-0.1 MPa; The drying condition comprises: drying at 100-150℃ for 5-12 h.

10. A soluble fiber inorganic ceramic board, characterized by, The method is prepared according to any one of claims 1-9.

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