Modified high-strength carbon material and preparation method thereof

Abstract

The invention belongs to the technical field of material modification, and particularly relates to a modified high-strength carbon material and a preparation method thereof.The modified high-strength carbon material is prepared from, by mass, 20 parts of modified carbon powder, 1-2 parts of hydroxylated compound, 2.5-4 parts of silane coupling agent, 0.5-1.5 parts of PVP, 0.5-1.5 parts of tetrabutyl titanate, 0.5 part of quartz powder, 0.4-0.8 part of talcum powder and 0.8-1.2 parts of coal ash; according to the invention, breakthrough is realized through multiple synergy: resistance is reduced through citric acid coordination, a starting point is formed through etching, and the efficiency bottleneck of a molten salt method is broken through; carbon powder hydroxylation and diatomite form a covalent bond reinforced interface, and secondary calcination enables defect carbon to be graphitized, so that the crystallinity is improved, and defects are reduced; thermal stress active site assisted grafting is matched with dispersion of a coupling agent and PVP, bonding is strengthened, uniformity is kept, and finally the mechanical strength and the structural consistency are synchronously improved.

Description

TECHNICAL FIELD

[0001] The application belongs to the technical field of material modification, and particularly relates to a modified high-strength carbon material and a preparation method thereof. BACKGROUND

[0002] Carbon-based composite materials are highly concerned in the field of structural materials due to their lightweight and high stability, but their further development faces the following bottlenecks:

[0003] Traditional physical mixing or weak adsorption cannot achieve strong combination of carbon phase and inorganic fillers, the interface stress transmission efficiency is low, resulting in insufficient mechanical strength; the carbon layer peeling efficiency is low, and the carbon structure is disordered and internal defects are accumulated during the composite process, further weakening the material integrity; although the existing improvement methods such as surface oxidation and coupling agent treatment can partially enhance the interface action, the bonding strength is limited; and the research on the coordinated regulation of carbon layer peeling and defect repair is insufficient, and it is difficult to simultaneously improve the material strength and structural consistency.

[0004] Based on the above, it is urgent to develop a strategy that can simultaneously achieve efficient carbon structure optimization and strong interface chemical bonding, so as to achieve a breakthrough in the performance of carbon-based composite materials. SUMMARY

[0005] In view of the defects of the prior art, the modified high-strength carbon material disclosed in the application breaks through the problems of large diffusion resistance and insufficient peeling starting point of the traditional molten salt method by combining molten salt peeling with citric acid, using the coordination of citric acid carboxyl and metal ions to reduce the diffusion resistance, and creating a peeling starting point by high-temperature weak acid etching, thereby forming a synergistic effect to improve the peeling efficiency; the interface bonding path of the Si-O-C covalent bond is formed by the dehydration condensation of the hydroxyl group of the carbon powder and the silicon hydroxyl group of the diatomaceous earth after the design of the carbon powder hydroxylation, and the local graphitization of the defective carbon is realized by means of secondary calcination, which not only strengthens the interface bonding force between carbon and inorganic fillers by chemical bonds, but also reduces internal defects and improves crystallinity by structure repair, thereby solving the shortcoming of weak interface bonding in traditional composites; the active sites generated by thermal stress provide a basis for subsequent grafting, and the ordered connection of the ethanol hydroxyl grafting, the silane coupling agent treatment and the PVP ball milling dispersion further strengthens the interface chemical bonding and ensures the structural uniformity, so that the synchronous improvement of mechanical strength and structural consistency is finally realized.

[0006] To achieve the above-mentioned purpose, the technical scheme adopted by the application is a modified high-strength carbon material, which comprises the following mass parts of preparation raw materials: modified carbon powder 20 parts, hydroxylated compound 1-2 parts, silane coupling agent 2.5-4 parts, PVP 0.5-1.5 parts, tetrabutyl titanate 0.5-1.5 parts, quartz powder 0.5 parts, talc powder 0.4-0.8 parts and fly ash 0.8-1.2 parts;

[0007] Further, the preparation method of the hydroxylated complex comprises the following steps:

[0008] a. Take 3-5 parts of diatomite, 1.5-2.5 parts of kaolin, 2 parts of montmorillonite and 0.5 parts of borax and add them into an alcohol-water mixture, wherein the alcohol-water mixture is composed of the following materials in a mass ratio: ethanol: water = 0.3: 0.7, ultrasonic for 20 min under the condition of a power of 20 kHZ, adjust the pH range to 8-10 by adding a sodium hydroxide solution with a concentration of 1 mol / L, then stir at a speed of 500 r / min for 30 min, and heat at a temperature of 80℃ for 2 h to obtain an alkaline activated substance;

[0009] b. Freeze the alkaline activated substance obtained in step a at a temperature of -40℃ for 24 h, and then dry it at a temperature of 65℃ for 24 h to obtain a hydroxylated complex precursor;

[0010] c. Add the hydroxylated complex precursor obtained in step b into a hydrogen peroxide solution with a volume concentration of 10%, stir at a speed of 500 r / min, heat at a temperature of 120℃ for 6 h, naturally cool to room temperature, wash with deionized water and anhydrous ethanol alternately for 3 times each, and then place it in a drying oven at a temperature of 65℃ for drying treatment for 24 h to obtain a hydroxylated complex.

[0011] Further, the preparation method of the modified carbon powder comprises the following steps:

[0012] α. Take 10 parts of high-purity carbon powder, 0.8-1.2 parts of a composite powder and 0.5 parts of citric acid and mix them, ball mill under the condition of a rotating speed of 300 r / min for 15 min, calcine at a temperature of 500℃ for 2 h at a heating rate of 5℃ / min, and introduce a mixed gas with a flow rate of 500 ml / min, wherein the mixed gas is composed of 95% argon and 5% hydrogen in a volume ratio to obtain an acidized exfoliate;

[0013] β. Take 1-2 parts of silicon nitride, 1.5-2 parts of ammonium boride and 2-4 parts of glucose and add them into the acidized exfoliate obtained in step α, ball mill under the condition of a rotating speed of 300 r / min for 15 min, calcine at a temperature of 900℃ for 2 h at a heating rate of 5℃ / min, and then calcine again at a temperature of 1200℃ for 1 h at a heating rate of 2℃ / min, and cool to room temperature at a cooling rate of 10℃ / min to obtain a modified carbon powder.

[0014] Further, the composite powder comprises the following raw materials in a mass ratio: LiCl: NaCl: CeCl3: malic acid: lignin = 1.5: 1: 0.4: 0.5: 0.1.

[0015] The application further provides a preparation method of the modified high-strength carbon material.

[0016] Step one: 1-2 parts of the hydroxylated compound are weighed and added into 50 parts of ethanol, and ultrasonic treatment is carried out at a power of 20 kHz for 20 min; 20 parts of the modified carbon powder are weighed and added into the mixture, and heating is carried out at a temperature of 60 DEG C for 30 min; stirring is carried out at a rotating speed of 500 r / min; and then filtration is carried out, so as to obtain a basic modified carbide;

[0017] Step two: 2.5-4 parts of the silane coupling agent are weighed and added into 50 parts of ethanol, and stirring is carried out at a rotating speed of 500 r / min for 10 min, so as to obtain a diluent; the basic modified carbide obtained in step one is added into the obtained diluent, and stirring is carried out at a rotating speed of 500 r / min for 10 min; heating is carried out at a temperature of 60 DEG C for 30 min; then filtration is carried out; and drying is carried out at a temperature of 80 DEG C for 24 h, so as to obtain a composite modified carbide;

[0018] Step three: 0.5 parts of quartz powder, 0.4-0.8 parts of talc powder, 0.8-1.2 parts of fly ash, 0.5-1.5 parts of PVP and the composite modified carbide obtained in step two are mixed, and ball milling is carried out at a rotating speed of 300 r / min for 15 min, so as to obtain a composite carbon powder material;

[0019] Step four: 0.5-1.5 parts of tetrabutyl titanate are weighed and added into 10 parts of ethanol, and stirring is carried out at a rotating speed of 500 r / min for 10 min, so as to obtain a uniform slurry; the obtained uniform slurry is added into the composite carbon powder material obtained in step three, and stirring is carried out at a rotating speed of 500 r / min for 10 min; heating is carried out from room temperature to 500 DEG C for 2 h; heating is carried out to 1200 DEG C on the basis of the foregoing temperature; argon gas with a flow rate of 500 ml / min is introduced; and natural cooling is carried out to room temperature, so as to obtain the modified high-strength carbon material.

[0020] The application has the following beneficial effects:

[0021] The modified high-strength carbon material prepared in the application is prepared by using high-purity carbon powder as a base material, stripping the surface carbon layer structure through a molten salt method, rapidly diffusing to the interlayer or surface gap of the high-purity carbon powder, increasing the carbon interlayer spacing through 'ion insertion', reducing the interlayer binding force, providing a basis for the compounding of coordination compounds, forming coordination compounds with metal ions in the molten salt through the carboxyl group of citric acid, reducing the diffusion resistance of ions between the carbon layers, and slightly etching the surface of the carbon powder through the weak acidity to destroy the local ordered structure and promote the formation of a stripping starting point; the stripped carbon powder is treated by surface hydroxylation to obtain a functional group rich in hydroxyl groups, and at high temperature, the calcination can occur with the silicon hydroxyl groups on the surface of diatomite to form Si-O-C covalent bonds, enhance the interfacial bonding force, and improve the overall strength of the carbon powder, and secondary co-heating can cause partial graphitization of part of the amorphous carbon powder, improve the crystallinity of the carbon powder, and reduce the internal defects of the composite material.

[0022] The modified high-strength carbon material prepared in the application is prepared by using high-purity carbon powder as a base material, stripping the surface carbon layer structure through a molten salt method, rapidly diffusing to the interlayer or surface gap of the high-purity carbon powder, increasing the carbon interlayer spacing through 'ion insertion', reducing the interlayer binding force, providing a basis for the compounding of coordination compounds, forming coordination compounds with metal ions in the molten salt through the carboxyl group of citric acid, reducing the diffusion resistance of ions between the carbon layers, and slightly etching the surface of the carbon powder through the weak acidity to destroy the local ordered structure and promote the formation of a stripping starting point; the stripped carbon powder is treated by surface hydroxylation to obtain a functional group rich in hydroxyl groups, and at high temperature, the calcination can occur with the silicon hydroxyl groups on the surface of diatomite to form Si-O-C covalent bonds, enhance the interfacial bonding force, and improve the overall strength of the carbon powder, and secondary co-heating can cause partial graphitization of part of the amorphous carbon powder, improve the crystallinity of the carbon powder, and reduce the internal defects of the composite material. BRIEF DESCRIPTION OF DRAWINGS

[0023] Figure 1 The preparation method of the modified high-strength carbon material proposed in the application is shown in the figure; Figure 2 The physical map of the modified high-strength carbon material prepared in Example 2 is shown in the figure; Figure 3 The TEM maps of the high-purity carbon powder before and after stripping in Example 2 are shown in the figure; Figure 4 The EPR map of the modified high-strength carbon material prepared in Example 2 is shown in the figure; Figure 5 The Vickers hardness test map of the modified high-strength carbon material prepared in the examples and the comparative examples is shown in the figure; Figure 6 The compression strength and bending strength test map of the modified high-strength carbon material prepared in the examples and the comparative examples is shown in the figure.

[0024] The accompanying drawings are used to provide a further understanding of the application, and constitute a part of the specification, together with the embodiments of the application, to explain the application, and do not constitute a limitation on the application. DETAILED DESCRIPTION

[0025] The technical solutions of the present invention will be clearly and completely described below with reference to the accompanying drawings of the embodiments of the present invention. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. All other embodiments obtained by those skilled in the art based on the embodiments of the present invention without creative effort are within the scope of protection of the present invention.

[0026] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as those familiar to those skilled in the art. Furthermore, any methods and materials similar to or equivalent to those described herein may be applied to this invention. The preferred embodiments and materials described herein are for illustrative purposes only and do not limit the scope of this application. The main components of the construction waste are concrete, the waste wood is sawdust, and the waste plastic is PET.

[0027] The preparation methods and related tests in the following examples are as follows: Figures 1-6 Unless otherwise specified, all methods are conventional. Unless otherwise specified, the proportions of materials used in the following examples are by mass. The alcohol-water mixture is composed of the following mass ratio: ethanol:water = 0.3:0.7. The composite powder includes the following mass ratio of raw materials: LiCl:NaCl:CeCl3:malic acid:lignin = 1.5:1:0.4:0.5:0.1.

[0028] Example 1: A modified high-strength carbon material, comprising the following raw materials in parts by weight: 20 parts modified carbon powder, 1 part hydroxylated compound, 2.5 parts silane coupling agent, 0.5 parts PVP, 0.5 parts tetrabutyl titanate, 0.5 parts quartz powder, 0.4 parts talc powder, and 0.8 parts fly ash;

[0029] The method for preparing the hydroxylated complex includes the following steps:

[0030] a. Weigh 3 parts diatomaceous earth, 1.5 parts kaolin, 2 parts montmorillonite and 0.5 parts borax and add them to the alcohol-water mixture. Sonicate for 20 min at 20 kHz. Adjust the pH to 8 with 1 mol / L sodium hydroxide solution. Then stir at 500 r / min for 30 min and heat at 80 ℃ for 2 h to obtain the alkaline activator.

[0031] b. The basic activator obtained in step a is quick-frozen at -40°C for 24 hours, and then dried at 65°C for 24 hours to obtain the hydroxylated complex precursor.

[0032] c. The hydroxylated complex precursor obtained in step b is added to 10% volume concentration hydrogen peroxide, stirred at 500 r / min, heated at 120°C for 6 h, naturally cooled to room temperature, washed with deionized water and anhydrous ethanol alternately for 3 times, and then dried in a 65°C air-drying oven for 24 h to obtain a hydroxylated complex.

[0033] A method for preparing modified carbon powder, comprising the following steps:

[0034] α. 10 parts of high-purity carbon powder, 0.8 parts of composite powder and 0.5 parts of citric acid are weighed and mixed, ball-milled at 300 r / min for 15 min, calcined at 500°C at a heating rate of 5°C / min for 2 h, and mixed gas (volume ratio: 95% argon and 5% hydrogen) is introduced at a flow rate of 500 ml / min to obtain acidified exfoliates;

[0035] β. 1 part of silicon nitride, 1.5 parts of ammonium boride and 2 parts of glucose are weighed and added to the acidified exfoliates obtained in step α, ball-milled at 300 r / min for 15 min, calcined at 900°C at a heating rate of 5°C / min for 2 h, and then heated to 1200°C at a heating rate of 2°C / min for secondary calcination for 1 h, and then cooled to room temperature at a cooling rate of 10°C / min to obtain modified carbon powder.

[0036] The embodiment also provides a method for preparing modified high-strength carbon material, comprising the following steps:

[0037] Step one. 1 part of hydroxylated complex is weighed and added to 50 parts of ethanol, ultrasonically treated at a power of 20 kHz for 20 min, 20 parts of modified carbon powder is weighed and added, stirred at 500 r / min at a temperature of 60°C for 30 min, and then filtered to obtain a basic modified carbide;

[0038] Step two. 2.5 parts of silane coupling agent is weighed and added to 50 parts of ethanol, stirred at 500 r / min for 10 min to obtain a diluent, the basic modified carbide obtained in step one is added to the obtained diluent, stirred at 500 r / min for 10 min, heated at a temperature of 60°C for 30 min, and then filtered and dried at 80°C for 24 h to obtain a composite modified carbide;

[0039] Step three. 0.5 parts of quartz powder, 0.4 parts of talc powder, 0.8 parts of fly ash, 0.5 parts of PVP and the composite modified carbide obtained in step two are mixed, and ball-milled at 300 r / min for 15 min to obtain a composite carbon powder material.

[0040] Step four. 0.5 parts of tetrabutyl titanate was weighed into 10 parts of ethanol, stirred at a speed of 500 r / min for 10 min to obtain a uniform slurry, the obtained uniform slurry was added to the composite carbon powder material obtained in step three, stirred at a speed of 500 r / min for 10 min, heated from room temperature to 500℃, calcined for 2h, heated to 1200℃ based on the foregoing temperature, and argon gas with a flow rate of 500 ml / min was introduced, and naturally cooled to room temperature to obtain a modified high-strength carbon material.

[0041] Example 2: A modified high-strength carbon material, comprising the following parts by mass of raw materials: modified carbon powder 20 parts, hydroxylated composite 1.5 parts, silane coupling agent 3.3 parts, PVP 1 part, tetrabutyl titanate 1 part, quartz powder 0.5 part, talc powder 0.6 part and fly ash 1 part;

[0042] The preparation method of the hydroxylated composite comprises the following steps:

[0043] a. 4 parts of diatomite, 2 parts of kaolin, 2 parts of montmorillonite and 0.5 parts of borax were weighed into an alcohol-water mixture, ultrasonic was performed under the condition of a power of 20 kHZ for 20 min, a sodium hydroxide solution with a concentration of 1 mol / L was added to adjust the pH to 9, then stirring was performed at a speed of 500 r / min for 30 min, and heating was performed under the condition of a temperature of 80℃ for 2h to obtain an alkaline activated material;

[0044] b. The alkaline activated material obtained in step a was rapidly frozen under the condition of a temperature of -40℃ for 24h, and then dried under the condition of a temperature of 65℃ for 24h to obtain a hydroxylated composite precursor;

[0045] c. The hydroxylated composite precursor obtained in step b was added into hydrogen peroxide with a volume concentration of 10%, stirring was performed at a speed of 500 r / min, heating was performed under the condition of a temperature of 120℃ for 6h, and natural cooling was performed to room temperature, deionized water and anhydrous ethanol were used for alternating washing for 3 times respectively, and then drying treatment was performed in a blowing drying box with a temperature of 65℃ for 24h to obtain a hydroxylated composite.

[0046] The preparation method of the modified carbon powder comprises the following steps:

[0047] α. 10 parts of high-purity carbon powder, 1 part of composite powder and 0.5 parts of citric acid were mixed, ball milling was performed under the condition of a speed of 300 r / min for 15 min, heating was performed at a rate of 5℃ / min, calcination was performed under the condition of a temperature of 500℃ for 2h, and mixed gas with a flow rate of 500 ml / min was introduced, the mixed gas was 95% argon and 5% hydrogen (volume ratio) to obtain acidized exfoliates;

[0048] β. Take 1.5 parts of silicon nitride, 1.8 parts of ammonium boride and 3 parts of glucose into the acidified exfoliate obtained in step α, and perform ball milling at a rotation speed of 300 r / min for 15 min. Perform calcination at a heating rate of 5℃ / min for 2 h at a temperature of 900℃, and then perform secondary calcination at a heating rate of 2℃ / min for 1 h at a temperature of 1200℃. Cool down to room temperature at a cooling rate of 10℃ / min to obtain the modified carbon powder.

[0049] The present embodiment also provides a preparation method of the modified high-strength carbon material, comprising the following steps:

[0050] Step one. Take 1.5 parts of the hydroxylated compound into 50 parts of ethanol, and perform ultrasonic treatment at a power of 20 kHz for 20 min. Take 20 parts of the modified carbon powder into the mixture, and perform heating at a temperature of 60℃ for 30 min. Stir at a rotation speed of 500 r / min, and then filter to obtain the basic modified carbon compound.

[0051] Step two. Take 3.3 parts of the silane coupling agent into 50 parts of ethanol, and stir at a rotation speed of 500 r / min for 10 min to obtain a diluent. Take the basic modified carbon compound obtained in step one into the diluent, and stir at a rotation speed of 500 r / min for 10 min. Perform heating at a temperature of 60℃ for 30 min, and then filter and dry at a temperature of 80℃ for 24 h to obtain the composite modified carbon compound.

[0052] Step three. Mix 0.5 parts of quartz powder, 0.6 parts of talc powder, 1 part of fly ash, 1 part of PVP and the composite modified carbon compound obtained in step two, and perform ball milling at a rotation speed of 300 r / min for 15 min to obtain the composite carbon powder material.

[0053] Step four. Take 1 part of tetrabutyl titanate into 10 parts of ethanol, and stir at a rotation speed of 500 r / min for 10 min to obtain a uniform slurry. Take the uniform slurry into the composite carbon powder material obtained in step three, and stir at a rotation speed of 500 r / min for 10 min. Perform calcination at a temperature of 500℃ for 2 h from room temperature, and then heat to a temperature of 1200℃ while introducing argon gas at a flow rate of 500 ml / min. Naturally cool to room temperature to obtain the modified high-strength carbon material.

[0054] Example 3: A modified high-strength carbon material, comprising the following parts by mass of raw materials: 20 parts of modified carbon powder, 2 parts of hydroxylated compound, 4 parts of silane coupling agent, 1.5 parts of PVP, 1.5 parts of tetrabutyl titanate, 0.5 parts of quartz powder, 0.8 parts of talc powder and 1.2 parts of fly ash.

[0055] A method for preparing a hydroxylated complex, comprising the following steps:

[0056] a. 5 parts of diatomite, 2.5 parts of kaolin, 2 parts of montmorillonite and 0.5 parts of borax are weighed and added into an alcohol-water mixture, and then ultrasonic treatment is performed for 20 min under the condition of a power of 20 kHz, a sodium hydroxide solution with a concentration of 1 mol / L is added to adjust the pH to 10, and then stirring is performed at a speed of 500 r / min for 30 min, and heating is performed at a temperature of 80℃ for 2 h to obtain an alkaline activated substance;

[0057] b. The alkaline activated substance obtained in step a is rapidly frozen at a temperature of -40℃ for 24 h, and then dried at a temperature of 65℃ for 24 h to obtain a hydroxylated complex precursor;

[0058] c. The hydroxylated complex precursor obtained in step b is added into a hydrogen peroxide solution with a volume concentration of 10%, and stirring is performed at a speed of 500 r / min, and heating is performed at a temperature of 120℃ for 6 h, and then naturally cooled to room temperature, and then washed with deionized water and anhydrous ethanol alternately for 3 times, and then placed in a blowing drying oven at a temperature of 65℃ for drying treatment for 24 h to obtain a hydroxylated complex.

[0059] A method for preparing a modified carbon powder, comprising the following steps:

[0060] α. 10 parts of high-purity carbon powder, 1.2 parts of composite powder and 0.5 parts of citric acid are weighed and mixed, and then ball milling is performed at a speed of 300 r / min for 15 min, and then calcination is performed at a temperature of 500℃ for 2 h at a heating rate of 5℃ / min, and then a mixed gas with a flow rate of 500 ml / min is introduced, and the mixed gas is composed of 95% argon and 5% hydrogen (by volume), to obtain an acidized exfoliate;

[0061] β. 2 parts of silicon nitride, 2 parts of ammonium boride and 4 parts of glucose are weighed and added into the acidized exfoliate obtained in step α, and then ball milling is performed at a speed of 300 r / min for 15 min, and then calcination is performed at a temperature of 900℃ for 2 h at a heating rate of 5℃ / min, and then secondary calcination is performed at a temperature of 1200℃ for 1 h at a heating rate of 2℃ / min, and then cooled to room temperature at a cooling rate of 10℃ / min to obtain a modified carbon powder.

[0062] The embodiment also provides a method for preparing a modified high-strength carbon material, comprising the following steps:

[0063] Step one. Take 2 parts of hydroxylated compound and add to 50 parts of ethanol, ultrasonic for 20 min under the condition of 20 kHZ, take 20 parts of modified carbon powder and add to the mixture, heat for 30 min under the condition of 60℃, stir at the speed of 500 r / min, then filter, to get the basic modified carbide;

[0064] Step two. Take 4 parts of silane coupling agent and add to 50 parts of ethanol, stir at the speed of 500 r / min for 10 min, to get the diluent, add the basic modified carbide obtained in step one to the diluent, stir at the speed of 500 r / min for 10 min, heat for 30 min under the condition of 60℃, then filter, dry at 80℃ for 24 h, to get the composite modified carbide;

[0065] Step three. Take 0.5 parts of quartz powder, 0.8 parts of talc powder, 1.2 parts of fly ash, 1.5 parts of PVP and the composite modified carbide obtained in step two, mix, ball mill for 15 min under the condition of 300 r / min, to get the composite carbon powder material;

[0066] Step four. Take 1.5 parts of tetrabutyl titanate and add to 10 parts of ethanol, stir at the speed of 500 r / min for 10 min, to get the uniform slurry, add the uniform slurry to the composite carbon powder material obtained in step three, stir at the speed of 500 r / min for 10 min, calcine for 2 h from room temperature to 500℃, heat to 1200℃ on the basis of the foregoing temperature, and pass argon gas with a flow rate of 500 ml / min, and naturally cool to room temperature, to get the modified high-strength carbon material.

[0067] Comparative example:

[0068] The difference between comparative example 1 and example 2 is that no hydroxylated compound is added, and the rest is the same as example 2;

[0069] The difference between comparative example 2 and example 2 is that the high-purity carbon powder is not modified, and the rest is the same as example 2;

[0070] The difference between comparative example 3 and example 2 is that step four only performs the first stage of calcination (500℃), and the rest is the same as example 2;

[0071] The high-purity carbon powder in comparative example 4 is not modified.

[0072] Figure 3 The TEM images of high-purity carbon powder before (a) and after (b) molten salt stripping can be seen that the edge of the carbon powder material after molten salt stripping is obviously thinner, exposing more active sites; Figure 4As shown in the ESR diagram of the high-purity carbon powder before the molten salt stripping, it can be seen that there are many active sites in the carbon powder after stripping, indicating that the molten salt stripping method can increase more defect sites on the surface of the carbon powder material and provide more active sites; further strength test was carried out on the prepared modified high-strength carbon material, as shown in Figure 5 The specific test conditions (GB / T 4340.1-2009) are shown: 10mm×10mm×5mm blocks are prepared, and the results show that the hardness of the modified carbon powder is higher than that of the unmodified high-purity carbon powder material, and further strength test results are shown in Figure 6 The specific test conditions are shown: 12mm×12mm×30mm blocks are prepared, and the results show that the compressive strength (GB / T 34559-2017) and bending strength (GB / T 40398.2-2021) of the modified high-strength carbon material prepared in the example are obviously improved compared with the comparative example, indicating that the modification method of the application can significantly improve the overall strength of the carbon powder material.

[0073] Obviously, the above comparative examples and examples are only a part of the comparative examples and examples of the application, and both of them are within the scope of protection of the application.

[0074] Although the embodiments of the application have been shown and described, it will be understood by those skilled in the art that various changes, modifications, substitutions and variations can be made to the embodiments without departing from the principles and spirit of the application, and the scope of the application is defined by the appended claims and their equivalents.

[0075] The above describes the application and its embodiments, which is not restrictive, and the embodiments shown in the drawings are only one of the embodiments of the application, and the actual application is not limited thereto. In summary, if a person skilled in the art is inspired by it, without departing from the purpose of the application, without creative design, similar ways and embodiments of the technical solution should belong to the protection scope of the application.

Claims

1. A modified high-strength carbon material, characterized in that, The raw materials include the following parts by weight: 20 parts modified carbon powder, 1-2 parts hydroxylated compound, 2.5-4 parts silane coupling agent, 0.5-1.5 parts PVP, 0.5-1.5 parts tetrabutyl titanate, 0.5 parts quartz powder, 0.4-0.8 parts talc powder, and 0.8-1.2 parts fly ash; The modified toner comprises the following raw materials in the following mass ratio: high-purity toner: composite powder: citric acid: silicon nitride: ammonium boride: glucose = 10: 0.8~1.2: 0.5: 1~2: 1.5~2: 2~4, and the composite powder comprises the following raw materials in the following mass ratio: LiCl: NaCl: CeCl3: malic acid: lignin = 1.5: 1: 0.4: 0.5: 0.1; The hydroxylated complex comprises raw materials in the following mass ratio: diatomaceous earth: kaolin: montmorillonite: borax = 3~5: 1.5~2.5: 2: 0.

5.

2. The modified high-strength carbon material according to claim 1, characterized in that, The method for preparing the hydroxylated complex includes the following steps: a. Add diatomaceous earth, kaolin, montmorillonite and borax to an alcohol-water mixture, sonicate, add alkali to adjust the pH, stir, heat, and obtain an alkaline activator. b. Quick-freeze the basic activator to obtain the hydroxylated complex precursor; c. Add the hydroxylated complex precursor to hydrogen peroxide, heat, and dry to obtain the hydroxylated complex.

3. The modified high-strength carbon material according to claim 2, characterized in that, The alcohol-water mixture described in step a consists of the following materials in the following mass ratio: ethanol:water = 0.3:0.7, the alkali is sodium hydroxide solution with a concentration of 1 mol / L, the pH range is 8~10, the quick-freezing temperature described in step b is -40℃, and the volume concentration of hydrogen peroxide described in step c is 10%.

4. The modified high-strength carbon material according to claim 1, characterized in that, The method for preparing the modified toner includes the following steps: α. Mix high-purity carbon powder, composite powder and citric acid, ball mill, calcine, and aerate to obtain acidified stripping material; β. Add silicon nitride, ammonium boride, and glucose to the acidified stripping material, ball mill, calcine, calcine again, and rapidly cool to obtain modified carbon powder.

5. The modified high-strength carbon material according to claim 4, characterized in that, The ventilation gas in step α is a mixture of gases in the following volume ratio: 95% argon and 5% hydrogen.

6. A method for preparing a modified high-strength carbon material as described in any one of claims 1 to 5, characterized in that, Includes the following steps: Step 1. Weigh the hydroxylated complex and add it to ethanol, sonicate, weigh the modified carbon powder and add it, stir to obtain the basic modified carbon compound; Step 2. Weigh the silane coupling agent and add it to ethanol, stir to obtain a diluted solution, add the basic modified carbide to the diluted solution, stir to obtain a composite modified carbide; Step 3. Weigh and mix quartz powder, talc powder, fly ash, PVP and composite modified carbide, ball mill to obtain composite carbon powder material; Step 4. Weigh tetrabutyl titanate and add it to ethanol, stir to obtain a uniform slurry, add the uniform slurry to the composite carbon powder material, stir, calcine to obtain the modified high-strength carbon material.

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