Refractory ceramic fiber board

Abstract

The invention relates to the technical field of fireproof protective materials for new energy automobile battery modules, and discloses a fireproof ceramic fiber board which comprises the following raw materials in parts by weight: 2000-3000 parts of water, 30-50 parts of ceramic fibers, 2-5 parts of silicon dioxide powder, 3-10 parts of ceramic forming filler, 5-15 parts of glass powder, 20-40 parts of modified silica sol and 0.5-1 part of a flocculating agent. The modified silica sol is prepared by modifying silica sol with a coupling agent a or a coupling agent b. The fire-resistant ceramic fiber board is not burnt through after being subjected to front surface firing for 30 min through flame at the temperature of 1500 DEG C, the surface of the fire-resistant ceramic fiber board is free of cracks, and the fire-resistant ceramic fiber board shows excellent fire resistance. The fire-resistant ceramic fiber board can be used as a fire-resistant protective material between battery modules of a new energy automobile, and has the effects of blocking flame impact and preventing thermal runaway of batteries from spreading.

Description

Technical Field

[0001] The present invention relates to the technical field of fire-resistant protective materials for new energy vehicle battery modules, and in particular to a fire-resistant ceramic fiberboard. Background Art

[0002] Ceramic fiberboard is a refractory material with high strength, excellent impact resistance, good thermal insulation performance and certain supporting function. It can be used as a fireproof material between battery modules of new energy vehicles. When the battery is overcharged, overheated, short-circuited, collided or squeezed and thermal runaway occurs, the ceramic fiberboard can effectively block the impact of flames and absorb the huge energy generated by the thermal runaway explosion, thereby preventing the battery thermal runaway from spreading and ensuring the safety of users' lives and property.

[0003] At present, ceramic fiberboards usually use silica sol as a binder. Although the ceramic fiberboards obtained from conventional inorganic silica sols have high hardness, they are brittle and easy to crack. In addition, during the actual burning process, due to the generation of small molecular byproduct water, the silica sol is easily decomposed by high temperature, resulting in the ceramic fiberboard being burned through. Summary of the invention

[0004] The present invention independently develops a refractory ceramic fiberboard, which can be used as a refractory protective material between battery modules of new energy vehicles, and plays a role in blocking flame impact and preventing the spread of thermal runaway of batteries.

[0005] A refractory ceramic fiberboard comprises the following raw materials:

[0006] 2000-3000 parts by weight of water;

[0007] 30-50 parts by weight of ceramic fiber;

[0008] 2-5 parts by weight of silicon dioxide powder;

[0009] 3-10 parts by weight of porcelain-forming filler;

[0010] 5-15 parts by weight of glass powder;

[0011] 20-40 parts by weight of modified silica sol;

[0012] 0.5-1 parts by weight of flocculant;

[0013] The preparation method of the modified silica sol is as follows: the silica sol is modified by coupling agent a or coupling agent b, and the silanol or zirconium hydroxyl functional groups obtained by hydrolysis of the coupling agent undergo dehydration condensation reaction with the hydroxyl functional groups contained in the silica sol to obtain the modified silica sol;

[0014] The mass ratio of coupling agent to silica sol in the modified silica sol is 1:(5-15).

[0015] Preferably, the preparation method of the coupling agent a is: an addition reaction is carried out between vinyloxytrimethylsilane and the Si-H functional group of dimethylethoxysilane, and the molar ratio of the vinyloxytrimethylsilane and dimethylethoxysilane participating in the reaction is controlled to be (1.01-1.09):1 to generate coupling agent a.

[0016] Preferably, the preparation method of the coupling agent b is:

[0017] The intermediate 1 is generated by allowing vinyloxytrimethylsilane to react with the Si-H functional group of dimethylsilyl POSS, and the molar ratio of the vinyloxytrimethylsilane and dimethylsilyl POSS involved in the reaction is controlled to be (8.01-8.09):1;

[0018] Intermediate 2 was synthesized by the vertex-opening method using intermediate 1 as a raw material and trifluoromethanesulfonic acid as an opening reagent;

[0019] Intermediate 2 was used as raw material and tetrabutyl zirconate was used as a capping agent to synthesize coupling agent b through the vertex-capping method.

[0020] Preferably, the ceramic fiber is one or a combination of more than one of aluminum silicate fiber, aluminum oxide fiber, mullite fiber, quartz fiber, silicon carbide fiber, zirconium oxide fiber and nitride fiber.

[0021] Preferably, the porcelain-forming filler is one or a combination of more than one of wollastonite, diatomaceous earth, kaolin, calcium carbonate and mica powder.

[0022] Preferably, the flocculant is one or a combination of more than one of polyacrylamide, polyethyleneimine, aluminum sulfate, ferric sulfate and polyaluminum chloride.

[0023] Preferably, the refractory ceramic fiberboard has a tensile strength of (12-17) MPa and does not burn through when burned at a temperature of 1500° C. for 30 minutes.

[0024] Beneficial effects:

[0025] The present invention designs and synthesizes coupling agent a and coupling agent b, and uses coupling agent a or coupling agent b to modify silica sol to prepare modified silica sol;

[0026] A refractory ceramic fiber board is prepared with aluminum silicate fiber as ceramic fiber raw material, silicon dioxide powder as stability enhancer, mica powder and calcium carbonate as ceramic fillers, glass powder as hardness enhancer, modified silica sol as binder and polyacrylamide as flocculant. On the one hand, the glass powder in the ceramic fiber board is melted by heat and works together with silicon dioxide powder and ceramic filler to form a dense ceramic layer, so that the ceramic fiber board does not crack after being burned at 1500°C for 30 minutes. On the other hand, the coupling agent in the modified silica sol provides a flexible surface layer for the silica sol, so that the stress between the surface layers of the silica sol can be evenly transferred, thereby enhancing the strength and toughness of the silica sol material, and achieving the beneficial technical effect of significantly improving the tensile strength, fire resistance and fire stability of the ceramic fiber board. DETAILED DESCRIPTION

[0027] Embodiment 1:

[0028] A refractory ceramic fiberboard, the raw material formula of which is shown in Table 1;

[0029] Table 1 Raw material formula of refractory ceramic fiberboard

[0030]

[0031]

[0032] The preparation method of the modified silica sol in Table 1 is as follows: the silica sol is modified by using a self-made coupling agent a or a coupling agent b, and the silanol or zirconium hydroxyl functional groups obtained by hydrolysis of the coupling agent react with the hydroxyl functional groups contained in the silica sol (purchased from Hubei Xinyuhong Biomedical Technology Co., Ltd.) to obtain the modified silica sol;

[0033] Among them, the mass ratio of coupling agent to silica sol in the modified silica sol is 1:10;

[0034] The chemical structure and preparation method of coupling agent a are described in Experimental Example 1; the chemical structure and preparation method of coupling agent b are described in Experimental Example 2.

[0035] Embodiment 2:

[0036] A method for preparing a refractory ceramic fiberboard comprises the following steps:

[0037] Step 1, preparing modified silica sol: adding 40g silica sol to 80mL anhydrous ethanol, stirring and mixing at room temperature for 10min, then adding 4g coupling agent, stirring and reacting at room temperature for 10min, then adding 20mL water, adjusting the solution pH to 4.5 with concentrated hydrochloric acid, stirring and mixing at room temperature for 10min, then heating to 40°C and stirring and reacting for 2h, and standing for 24h to obtain modified silica sol;

[0038] Step 2: prepare a ceramic mixed solution: add 40 g of aluminum silicate fiber to 2500 mL of water, use a high-speed stirrer to stir and disperse at 2000 rpm for 30 min, then add 3 g of silicon dioxide powder, 2 g of mica powder, 3 g of calcium carbonate and 10 g of glass powder in sequence, keep stirring and dispersing at 2000 rpm for 15 min to obtain a ceramic mixed solution;

[0039] Step 3, preparing a ceramic mixed slurry: adding 30 g of the modified silica sol prepared in step 1 to the ceramic mixed solution prepared in step 2, stirring and dispersing at 1000 rpm for 30 min using a high-speed stirrer, and finally adding 0.8 g of polyacrylamide to obtain a ceramic mixed slurry;

[0040] Step 4, preparing a refractory ceramic fiberboard: pouring the ceramic mixed slurry prepared in step 3 into a mold for dehydration and forming, hot pressing and drying (hot pressing pressure 5.5 MPa, drying temperature 150° C., time 10 min) to obtain a refractory ceramic fiberboard;

[0041] When the coupling agent is coupling agent a, the prepared product is recorded as refractory ceramic fiberboard I;

[0042] When the coupling agent is coupling agent b, the prepared product is recorded as refractory ceramic fiberboard II.

[0043] Performance Test:

[0044] (1) Tensile strength test: The tensile strength of the sample was tested in accordance with GB / T 17911-2018;

[0045] (2) Fire resistance test: Maintain 1500℃ flame burning for 30 minutes and observe whether the sample is burned through;

[0046] (3) Fire resistance stability test: Burn the sample with a 1000°C flame for 20 seconds, then impact the sample with 1MPa gas for 5 seconds. This is one cycle. Observe whether the sample is burned through after 20 cycles.

[0047] The above performance test results are shown in Table 2;

[0048] Table 2 Performance test results of refractory ceramic fiberboard

[0049]

[0050] Note: The difference between the comparative example and the refractory ceramic fiberboard is that the modified silica sol is replaced by silica sol;

[0051] From the performance test results in Table 2, the following conclusions are obtained:

[0052] Conclusion 1: The refractory ceramic fiberboard product developed by the present invention does not burn through and has no cracks on the surface after being burned positively at 1500°C for 30 minutes, showing excellent fire resistance;

[0053] Conclusion 2: Compared with the ceramic fiberboard using conventional silica sol, the ceramic fiberboard prepared by modifying the silica sol using the homemade coupling agent a or coupling agent b in the present invention has achieved significant improvement in tensile strength, fire resistance and fire stability.

[0054] Experimental Example 1:

[0055] Preparation of coupling agent a: The Si-H functional group of vinyloxytrimethylsilane and dimethylethoxysilane undergoes an addition reaction, and the molar ratio of vinyloxytrimethylsilane and dimethylethoxysilane participating in the reaction is controlled to be 1.05:1, thereby generating coupling agent a, whose chemical structure is:

[0056]

[0057] The specific experimental steps for preparing coupling agent a are as follows: under the protection of nitrogen, 1.0 g of dimethylethoxysilane and 20 mL of anhydrous tetrahydrofuran are added to a three-necked flask, stirred at room temperature until completely dissolved, and then 1.5 mL of vinyloxytrimethylsilane and 2 drops of Custer catalyst are added dropwise to the three-necked flask, the temperature is raised to 70° C., stirred and refluxed for reaction for 8 h, cooled to room temperature, the solvent is removed by rotary evaporation, and vacuum dried to obtain coupling agent a;

[0058] The nuclear magnetic resonance hydrogen spectrum of coupling agent a is characterized as follows: 1 H NMR (CDCl3, 400MHz) δ: 0.08 (s, 6H), 0.14 (s, 9H), 0.90-0.94 (t, 2H), 1.08-1.12 (t, 3H), 3.57-3.61 (t, 2H), 3.67-3.73 (m, 2H).

[0059] Experimental Example 2:

[0060] Prepare coupling agent b, the preparation steps are:

[0061] Step 1: Vinyloxytrimethylsilane is reacted with the Si-H functional group of dimethylsilyl POSS by addition reaction, and the molar ratio of vinyloxytrimethylsilane and dimethylsilyl POSS participating in the reaction is controlled to be 8.08:1 to generate intermediate 1, whose chemical structure is:

[0062]

[0063] Step 2: Using intermediate 1 as raw material and trifluoromethanesulfonic acid as an opening reagent, intermediate 2 is synthesized by the vertex-opening method, and its chemical structure is:

[0064]

[0065] Step 3: Using intermediate 2 as raw material and tetrabutyl zirconate as capping agent, coupling agent b is synthesized by vertex-capping method, and its chemical structure is:

[0066]

[0067] The specific experimental steps for preparing coupling agent b are as follows:

[0068] Under nitrogen protection, 5.1 g of dimethylsilyl POSS and 50 mL of anhydrous tetrahydrofuran were added to a three-necked flask and stirred at room temperature until all dissolved. Then, 6.0 mL of vinyloxytrimethylsilane and 5 drops of Custer catalyst were added dropwise to the three-necked flask. The temperature was raised to 70 ° C. and stirred under reflux for 12 h. The mixture was cooled to room temperature, the solvent was removed by rotary evaporation, and the mixture was dried in vacuo to obtain intermediate 1.

[0069] 6.4 g of intermediate 1 and 80 mL of anhydrous tetrahydrofuran were added to a three-necked flask and stirred at room temperature until all dissolved. Then, 7.5 g of trifluoromethanesulfonic acid was added to the three-necked flask and stirred at room temperature for 0.5 h. After the reaction was completed, the reaction was filtered, and 5A molecular sieves were added to absorb and remove the residual trifluoromethanesulfonic acid. The solvent was removed by rotary evaporation and dried in vacuo to obtain intermediate 2.

[0070] Under nitrogen protection, 4.3 g of intermediate 2 and 50 mL of anhydrous tetrahydrofuran were added to a three-necked flask, stirred at room temperature until completely dissolved, and then placed in an ice-water bath. 1.0 mL of tetrabutyl zirconate was added dropwise to the three-necked flask, stirred in the ice-water bath for 30 min, and then the ice-water bath was removed. The stirring reaction was continued at room temperature for 6 h, the solvent was removed by rotary evaporation, and the solution was concentrated to a saturated solution. Acetonitrile was used for precipitation, filtration, washing, and vacuum drying to obtain coupling agent b;

[0071] The nuclear magnetic resonance hydrogen spectrum of coupling agent b is characterized as follows: 1 H NMR (CDCl3, 400MHz) δ: 0.06 (s, 42H), 0.12 (s, 63H), 0.85-0.89 (t, 3H), 0.97-1.00 (t , 14H), 1.39-1.49(m, 2H), 1.67-1.74(m, 2H), 3.60-3.63(t, 14H), 3.75-3.78(t, 2H).

Claims

1. A refractory ceramic fiberboard, characterized in that: Including the following ingredients: 2000-3000 parts by weight of water; 30-50 parts by weight of ceramic fiber; 2-5 parts by weight of silicon dioxide powder; 3-10 parts by weight of porcelain-forming filler; 5-15 parts by weight of glass powder; 20-40 parts by weight of modified silica sol; 0.5-1 parts by weight of flocculant; The preparation method of the modified silica sol is as follows: the silica sol is modified by coupling agent a or coupling agent b, and the silanol or zirconium hydroxyl functional groups obtained by hydrolysis of the coupling agent undergo dehydration condensation reaction with the hydroxyl functional groups contained in the silica sol to obtain the modified silica sol; The mass ratio of coupling agent to silica sol in the modified silica sol is 1:(5-15).

2. A refractory ceramic fiberboard according to claim 1, characterized in that: The chemical structural formula of the coupling agent a is:

3. A refractory ceramic fiberboard according to claim 2, characterized in that: The preparation method of the coupling agent a is as follows: vinyloxytrimethylsilane and the Si-H functional group of dimethylethoxysilane undergo an addition reaction, and the molar ratio of vinyloxytrimethylsilane and dimethylethoxysilane participating in the reaction is controlled to be (1.01-1.09):1, thereby generating the coupling agent a.

4. A refractory ceramic fiberboard according to claim 1, characterized in that: The chemical structural formula of the coupling agent b is:

5. A refractory ceramic fiberboard according to claim 4, characterized in that: The preparation method of the coupling agent b is: The intermediate 1 is generated by allowing vinyloxytrimethylsilane to react with the Si-H functional group of dimethylsilyl POSS, and the molar ratio of the vinyloxytrimethylsilane and dimethylsilyl POSS involved in the reaction is controlled to be (8.01-8.09):1; Intermediate 2 was synthesized by the vertex-opening method using intermediate 1 as a raw material and trifluoromethanesulfonic acid as an opening reagent; Intermediate 2 was used as raw material and tetrabutyl zirconate was used as a capping agent to synthesize coupling agent b through the vertex-capping method.

6. The refractory ceramic fiberboard according to claim 1, characterized in that: The ceramic fiber is one or a combination of more than one of aluminum silicate fiber, aluminum oxide fiber, mullite fiber, quartz fiber, silicon carbide fiber, zirconium oxide fiber and nitride fiber.

7. The refractory ceramic fiberboard according to claim 1, characterized in that: The ceramic filler is one or a combination of wollastonite, diatomaceous earth, kaolin, calcium carbonate and mica powder.

8. The refractory ceramic fiberboard according to claim 1, characterized in that: The flocculant is one or a combination of more than one of polyacrylamide, polyethyleneimine, aluminum sulfate, ferric sulfate and polyaluminum chloride.

9. A refractory ceramic fiberboard according to any one of claims 1 to 8, characterized in that: The refractory ceramic fiberboard has a tensile strength of (12-17) MPa and does not burn through when burning at a temperature of 1500° C. for 30 minutes.

10. The use of a refractory ceramic fiberboard according to any one of claims 1 to 8, characterized in that: Refractory ceramic fiberboard is used as a fire-resistant protective material between battery modules of new energy vehicles, which can block the impact of flames and prevent the spread of thermal runaway of batteries.

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