CN116216662A - Synthesis method of silicon nitride powder - Google Patents
Synthesis method of silicon nitride powder Download PDFInfo
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- CN116216662A CN116216662A CN202310049031.5A CN202310049031A CN116216662A CN 116216662 A CN116216662 A CN 116216662A CN 202310049031 A CN202310049031 A CN 202310049031A CN 116216662 A CN116216662 A CN 116216662A
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- 239000000843 powder Substances 0.000 title claims abstract description 59
- 229910052581 Si3N4 Inorganic materials 0.000 title claims abstract description 55
- HQVNEWCFYHHQES-UHFFFAOYSA-N silicon nitride Chemical compound N12[Si]34N5[Si]62N3[Si]51N64 HQVNEWCFYHHQES-UHFFFAOYSA-N 0.000 title claims abstract description 54
- 238000001308 synthesis method Methods 0.000 title claims description 7
- 238000005121 nitriding Methods 0.000 claims abstract description 68
- 238000006243 chemical reaction Methods 0.000 claims abstract description 46
- IJGRMHOSHXDMSA-UHFFFAOYSA-N Atomic nitrogen Chemical compound N#N IJGRMHOSHXDMSA-UHFFFAOYSA-N 0.000 claims abstract description 33
- 238000000034 method Methods 0.000 claims abstract description 29
- 238000000498 ball milling Methods 0.000 claims abstract description 24
- 239000002994 raw material Substances 0.000 claims abstract description 22
- 229910052757 nitrogen Inorganic materials 0.000 claims abstract description 21
- XUIMIQQOPSSXEZ-UHFFFAOYSA-N Silicon Chemical compound [Si] XUIMIQQOPSSXEZ-UHFFFAOYSA-N 0.000 claims abstract description 17
- 239000003054 catalyst Substances 0.000 claims abstract description 16
- 239000011863 silicon-based powder Substances 0.000 claims abstract description 16
- VVQNEPGJFQJSBK-UHFFFAOYSA-N Methyl methacrylate Chemical compound COC(=O)C(C)=C VVQNEPGJFQJSBK-UHFFFAOYSA-N 0.000 claims abstract description 15
- 125000002924 primary amino group Chemical group [H]N([H])* 0.000 claims abstract description 13
- GRYLNZFGIOXLOG-UHFFFAOYSA-N Nitric acid Chemical compound O[N+]([O-])=O GRYLNZFGIOXLOG-UHFFFAOYSA-N 0.000 claims abstract description 12
- 229910017604 nitric acid Inorganic materials 0.000 claims abstract description 12
- 239000000047 product Substances 0.000 claims description 74
- CSCPPACGZOOCGX-UHFFFAOYSA-N Acetone Chemical compound CC(C)=O CSCPPACGZOOCGX-UHFFFAOYSA-N 0.000 claims description 58
- 238000010438 heat treatment Methods 0.000 claims description 45
- ZMXDDKWLCZADIW-UHFFFAOYSA-N N,N-Dimethylformamide Chemical compound CN(C)C=O ZMXDDKWLCZADIW-UHFFFAOYSA-N 0.000 claims description 42
- 238000005406 washing Methods 0.000 claims description 30
- 238000001035 drying Methods 0.000 claims description 23
- FAPWRFPIFSIZLT-UHFFFAOYSA-M Sodium chloride Chemical compound [Na+].[Cl-] FAPWRFPIFSIZLT-UHFFFAOYSA-M 0.000 claims description 22
- MCMNRKCIXSYSNV-UHFFFAOYSA-N Zirconium dioxide Chemical compound O=[Zr]=O MCMNRKCIXSYSNV-UHFFFAOYSA-N 0.000 claims description 16
- 239000012298 atmosphere Substances 0.000 claims description 16
- 239000012299 nitrogen atmosphere Substances 0.000 claims description 15
- UFHFLCQGNIYNRP-UHFFFAOYSA-N Hydrogen Chemical compound [H][H] UFHFLCQGNIYNRP-UHFFFAOYSA-N 0.000 claims description 14
- 239000001257 hydrogen Substances 0.000 claims description 14
- 229910052739 hydrogen Inorganic materials 0.000 claims description 14
- IYTXQZMZTQHONB-UHFFFAOYSA-N 4-[(4-aminophenoxy)-dimethylsilyl]oxyaniline Chemical compound C=1C=C(N)C=CC=1O[Si](C)(C)OC1=CC=C(N)C=C1 IYTXQZMZTQHONB-UHFFFAOYSA-N 0.000 claims description 11
- 239000011780 sodium chloride Substances 0.000 claims description 11
- 239000000243 solution Substances 0.000 claims description 11
- HPNMFZURTQLUMO-UHFFFAOYSA-N diethylamine Chemical compound CCNCC HPNMFZURTQLUMO-UHFFFAOYSA-N 0.000 claims description 10
- 238000002156 mixing Methods 0.000 claims description 10
- PVFOMCVHYWHZJE-UHFFFAOYSA-N trichloroacetyl chloride Chemical compound ClC(=O)C(Cl)(Cl)Cl PVFOMCVHYWHZJE-UHFFFAOYSA-N 0.000 claims description 10
- 238000000926 separation method Methods 0.000 claims description 9
- ZVWKZXLXHLZXLS-UHFFFAOYSA-N zirconium nitride Chemical compound [Zr]#N ZVWKZXLXHLZXLS-UHFFFAOYSA-N 0.000 claims description 9
- 238000001816 cooling Methods 0.000 claims description 8
- 238000000227 grinding Methods 0.000 claims description 7
- 239000000463 material Substances 0.000 claims description 7
- 239000011259 mixed solution Substances 0.000 claims description 7
- 230000007935 neutral effect Effects 0.000 claims description 7
- 239000002244 precipitate Substances 0.000 claims description 7
- 238000010992 reflux Methods 0.000 claims description 7
- 229910021642 ultra pure water Inorganic materials 0.000 claims description 7
- 239000012498 ultrapure water Substances 0.000 claims description 7
- 238000001132 ultrasonic dispersion Methods 0.000 claims description 7
- 239000003085 diluting agent Substances 0.000 claims description 6
- 150000002736 metal compounds Chemical class 0.000 claims description 6
- 238000001291 vacuum drying Methods 0.000 claims description 6
- 229910010413 TiO 2 Inorganic materials 0.000 claims description 2
- 230000002194 synthesizing effect Effects 0.000 claims 9
- RVTZCBVAJQQJTK-UHFFFAOYSA-N oxygen(2-);zirconium(4+) Chemical compound [O-2].[O-2].[Zr+4] RVTZCBVAJQQJTK-UHFFFAOYSA-N 0.000 claims 1
- 229910001928 zirconium oxide Inorganic materials 0.000 claims 1
- 239000002245 particle Substances 0.000 abstract description 17
- 230000008569 process Effects 0.000 abstract description 10
- 230000015572 biosynthetic process Effects 0.000 abstract description 9
- 238000003786 synthesis reaction Methods 0.000 abstract description 9
- 229910052751 metal Inorganic materials 0.000 abstract description 7
- 239000002184 metal Substances 0.000 abstract description 7
- 150000003839 salts Chemical class 0.000 abstract description 6
- 239000012535 impurity Substances 0.000 abstract description 4
- 239000006185 dispersion Substances 0.000 abstract description 3
- 238000001764 infiltration Methods 0.000 abstract description 2
- 230000008595 infiltration Effects 0.000 abstract description 2
- 238000001179 sorption measurement Methods 0.000 abstract description 2
- 238000010189 synthetic method Methods 0.000 abstract 1
- 238000005303 weighing Methods 0.000 description 15
- 238000009826 distribution Methods 0.000 description 8
- 230000000052 comparative effect Effects 0.000 description 4
- 229910052749 magnesium Inorganic materials 0.000 description 4
- 239000011777 magnesium Substances 0.000 description 4
- -1 magnesium nitride Chemical class 0.000 description 4
- 230000009471 action Effects 0.000 description 3
- VYPSYNLAJGMNEJ-UHFFFAOYSA-N Silicium dioxide Chemical compound O=[Si]=O VYPSYNLAJGMNEJ-UHFFFAOYSA-N 0.000 description 2
- GWEVSGVZZGPLCZ-UHFFFAOYSA-N Titan oxide Chemical compound O=[Ti]=O GWEVSGVZZGPLCZ-UHFFFAOYSA-N 0.000 description 2
- 238000005054 agglomeration Methods 0.000 description 2
- 230000002776 aggregation Effects 0.000 description 2
- 238000005049 combustion synthesis Methods 0.000 description 2
- UQSXHKLRYXJYBZ-UHFFFAOYSA-N iron oxide Inorganic materials [Fe]=O UQSXHKLRYXJYBZ-UHFFFAOYSA-N 0.000 description 2
- 238000005259 measurement Methods 0.000 description 2
- 230000004048 modification Effects 0.000 description 2
- 238000012986 modification Methods 0.000 description 2
- NDLPOXTZKUMGOV-UHFFFAOYSA-N oxo(oxoferriooxy)iron hydrate Chemical compound O.O=[Fe]O[Fe]=O NDLPOXTZKUMGOV-UHFFFAOYSA-N 0.000 description 2
- 230000009467 reduction Effects 0.000 description 2
- 239000000126 substance Substances 0.000 description 2
- 238000002441 X-ray diffraction Methods 0.000 description 1
- 125000003277 amino group Chemical group 0.000 description 1
- 239000012752 auxiliary agent Substances 0.000 description 1
- 230000009286 beneficial effect Effects 0.000 description 1
- 230000003197 catalytic effect Effects 0.000 description 1
- 239000000919 ceramic Substances 0.000 description 1
- 238000001514 detection method Methods 0.000 description 1
- 230000000694 effects Effects 0.000 description 1
- 238000000713 high-energy ball milling Methods 0.000 description 1
- 125000002887 hydroxy group Chemical group [H]O* 0.000 description 1
- 230000006872 improvement Effects 0.000 description 1
- 238000007561 laser diffraction method Methods 0.000 description 1
- 239000011859 microparticle Substances 0.000 description 1
- 230000003647 oxidation Effects 0.000 description 1
- 238000007254 oxidation reaction Methods 0.000 description 1
- 230000035484 reaction time Effects 0.000 description 1
- 230000009257 reactivity Effects 0.000 description 1
- 239000000377 silicon dioxide Substances 0.000 description 1
- 235000012239 silicon dioxide Nutrition 0.000 description 1
- 239000004408 titanium dioxide Substances 0.000 description 1
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- C—CHEMISTRY; METALLURGY
- C01—INORGANIC CHEMISTRY
- C01B—NON-METALLIC ELEMENTS; COMPOUNDS THEREOF; METALLOIDS OR COMPOUNDS THEREOF NOT COVERED BY SUBCLASS C01C
- C01B21/00—Nitrogen; Compounds thereof
- C01B21/06—Binary compounds of nitrogen with metals, with silicon, or with boron, or with carbon, i.e. nitrides; Compounds of nitrogen with more than one metal, silicon or boron
- C01B21/068—Binary compounds of nitrogen with metals, with silicon, or with boron, or with carbon, i.e. nitrides; Compounds of nitrogen with more than one metal, silicon or boron with silicon
- C01B21/0682—Preparation by direct nitridation of silicon
-
- C—CHEMISTRY; METALLURGY
- C01—INORGANIC CHEMISTRY
- C01P—INDEXING SCHEME RELATING TO STRUCTURAL AND PHYSICAL ASPECTS OF SOLID INORGANIC COMPOUNDS
- C01P2004/00—Particle morphology
- C01P2004/60—Particles characterised by their size
- C01P2004/61—Micrometer sized, i.e. from 1-100 micrometer
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- C—CHEMISTRY; METALLURGY
- C01—INORGANIC CHEMISTRY
- C01P—INDEXING SCHEME RELATING TO STRUCTURAL AND PHYSICAL ASPECTS OF SOLID INORGANIC COMPOUNDS
- C01P2004/00—Particle morphology
- C01P2004/60—Particles characterised by their size
- C01P2004/62—Submicrometer sized, i.e. from 0.1-1 micrometer
-
- Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
- Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
- Y02P—CLIMATE CHANGE MITIGATION TECHNOLOGIES IN THE PRODUCTION OR PROCESSING OF GOODS
- Y02P20/00—Technologies relating to chemical industry
- Y02P20/10—Process efficiency
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- Ceramic Products (AREA)
Abstract
The invention relates to the technical field of silicon nitride powder, in particular to a synthetic method of silicon nitride powder; the silicon nitride synthesis process provided by the invention firstly uses ball milling treatment, reduces the particle size of raw materials, removes a surface oxide layer, accelerates the infiltration rate of nitrogen, accelerates nitriding reaction, then uses a metal catalyst and molten salt to adsorb on the surface of silicon powder at high temperature, accelerates the adsorption of nitrogen, further improves the nitriding rate, and the metal catalyst and molten salt used by the invention are both soluble in nitric acid solution with the concentration of 20-30wt%, so that impurity elements are further removed; and then, amino active groups are further grafted on the surface of the silicon nitride, so that active free radicals are generated, and methyl methacrylate is grafted, so that the dispersion performance of the silicon nitride is improved.
Description
Technical Field
The invention relates to the technical field of silicon nitride powder, in particular to a synthesis method of silicon nitride powder.
Background
The silicon nitride powder is used as a high-performance ceramic powder, has excellent mechanical property and chemical stability, and has the characteristics of high strength, excellent heat conductivity, strong oxidation resistance and the likeThe existing methods for preparing silicon nitride powder mainly comprise a silicon powder direct nitriding method, a carbothermic reduction silicon dioxide method, a self-propagating combustion synthesis method and the like. The traditional silicon powder direct nitriding method has the advantages of simple process, low cost, long process time and high required reaction temperature; the carbothermal reduction method has simple equipment and short process time, and the prepared Si 3 N 4 The powder has high purity, small particle size and a large amount of alpha phase, but also needs high reaction temperature and is difficult to control the C content in the reaction; the self-propagating combustion synthesis method does not need high reaction temperature, has short nitriding time, and is difficult to control the reaction process. One of the effective ways to improve the nitridation of silicon powder is to add a catalyst, and a metal catalyst is commonly used, but the metal catalyst has higher activity and is easy to agglomerate, and in the synthesis method, the siliceous raw material is often prepared into micro-or nano-scale micro-particles, so that the silicon powder has higher surface energy and is easy to agglomerate, the finally prepared silicon nitride powder is easy to agglomerate, and is difficult to disperse and finally the use is influenced.
Disclosure of Invention
The invention aims to provide a synthesis method of silicon nitride powder, which aims to solve the problems in the background technology.
In order to solve the technical problems, the invention provides the following technical scheme: the synthesis method of the silicon nitride powder comprises the following steps:
s1, mixing silicon powder, a diluent, a catalyst and NaCl in a nitrogen atmosphere, and ball-milling for 3-6 hours to obtain a mixed raw material;
s2, heating the mixed raw materials in a hydrogen atmosphere, heating to 1300 ℃ at a speed of 3-5 ℃/min, switching to a hydrogen-nitrogen mixed atmosphere, heating to 1300-1450 ℃, continuing to keep the temperature, stopping heating after nitriding for 3-6h, and cooling to room temperature along with a furnace to obtain a nitriding product;
s3, dispersing the nitriding product into a nitric acid solution with the concentration of 20-30wt%, performing ultrasonic dispersion for 3-4 hours, performing centrifugal separation, washing the precipitate to be neutral by using ultrapure water, and performing vacuum drying for 6-8 hours;
s4, dispersing the nitrided product treated in the step S3 into acetone, dropwise adding bis (4-aminophenoxy) dimethylsilane, heating to 45-60 ℃, carrying out ultrasonic vibration treatment for 1-4 hours, centrifugally separating the nitrided product, washing 2-3 times by using acetone, and carrying out vacuum drying until the weight is constant to obtain an amino-modified nitrided product;
s5, dispersing the amino-modified nitridation product into a mixed solution of N, N-dimethylformamide and diethylamine, ultrasonically dispersing for 1-2 hours, adding trichloroacetyl chloride, carrying out reflux reaction for 6-8 hours, carrying out centrifugal separation, washing for 3-5 times by using acetone, and carrying out vacuum drying to constant weight to obtain an active nitridation product;
s6, adding the active nitriding product and methyl methacrylate into N, N-dimethylformamide, protecting in nitrogen atmosphere, heating to 50-65 ℃, reacting for 4-8 hours, centrifugally separating, washing for 5-8 times by using acetone, and drying in vacuum to obtain silicon nitride powder.
In order to improve the synthesis purity of the silicon nitride powder and reduce the reaction conditions, the high-energy ball milling technology is firstly used, the ball milling is utilized to further crush the siliceous raw material and various catalytic auxiliary agents, various raw materials are mixed while the size and the particle diameter are reduced, and the siliceous raw material and various components are ensured to be uniformly mixed; in addition, in the crushing process, the high-speed collision can damage the surface oxide layer of the powder, so that the speed of the subsequent nitriding reaction is promoted, and the time cost and the energy cost are reduced.
On the basis, the invention further uses the catalyst and molten salt NaCl as nitriding media to further accelerate the process of nitriding reaction, the catalyst and NaCl can be adsorbed on the surface of siliceous raw materials at high temperature to accelerate the nitriding reaction of silicon atoms and nitrogen, so that the reaction time is reduced, and in the post-treatment process, nitric acid solution is used for washing the silicon nitride powder, and the catalyst and molten salt used in the invention can be dissolved in the nitric acid solution with the concentration of 20-30wt%, so that the silicon nitride powder prepared by the invention contains inorganic metal impurities, and the purity of the silicon nitride powder is improved.
In order to solve the problem of easy agglomeration of silicon nitride powder, methyl methacrylate is further grafted on the surface of the silicon nitride powder, various impurities contained in a nitriding product are removed by using nitric acid solution, a large amount of hydroxyl groups are grafted on the surface of the nitriding product, then bis (4-aminophenoxy) dimethyl silane is used again, amino groups are grafted on the surface of the nitriding product, so that the reactivity of surface groups is enhanced, the surface groups react with trichloroacetyl chloride, active free radicals are generated in the presence of diethylamine, the active free radicals are mixed with the methyl methacrylate, and the methyl methacrylate is grafted on the surface of the nitriding product, so that the dispersion performance of the nitriding product is improved, and agglomeration is prevented.
Further, in the step S1, the mass ratio of the silicon powder, the diluent, the catalyst and NaCl is 10: (3-5): (0.35-1.2): (3-5).
Further, the catalyst consists of zirconia, zirconium nitride and other metal compounds;
wherein, the mass ratio of the zirconia, the zirconium nitride and other metal compounds is (0.1-0.3) according to the weight parts: (0.1-0.4): (0.15-0.5).
Further, the diluent is Si 3 N 4 Powder; the metal compound is Fe 2 O 3 、TiO 2 、3Y-ZrO 2 、MgO、MgSiN 2 Any one or more of MgN.
Further, during ball milling, the ball-to-material ratio in the ball mill is 3:1, the grain diameter of the grinding balls is 3-6mm, and the ball milling rotating speed is 450-600rpm.
Further, in step S2, the nitriding temperature is 1300-1450 ℃;
wherein when heating, the temperature is raised to 25-900 ℃, and the reaction air pressure is 0.4-0.6MPa; when the temperature is raised to 900-1200 ℃, the air pressure is 2-3MPa; when the temperature is raised to 1200-1250 ℃, the air pressure is reduced to 1-1.5MPa, and when the temperature is raised to 1250-1450 ℃, the air pressure is 0.2-0.3MPa.
Further, in the step S2, in the hydrogen-nitrogen mixing atmosphere, the volume ratio of nitrogen to hydrogen is (88-92): (8-12).
Further, in the step S4, the mass ratio of the nitridation product to bis (4-aminophenoxy) dimethylsilane is 10: (0.5-1.5).
Further, in the step S5, the mass ratio of the amino-modified nitridation product to diethylamine to trichloroacetyl chloride is 10: (3-4.5): (0.5-1.5).
Further, in the step S6, the mass ratio of the active nitriding product to the methyl methacrylate is 10: (0.5-1.5).
Compared with the prior art, the invention has the following beneficial effects: the silicon nitride synthesis process provided by the invention firstly uses ball milling treatment, reduces the particle size of raw materials, removes a surface oxide layer, accelerates the infiltration rate of nitrogen, accelerates nitriding reaction, then uses a metal catalyst and molten salt to adsorb on the surface of silicon powder at high temperature, accelerates the adsorption of nitrogen, further improves the nitriding rate, and the metal catalyst and molten salt used by the invention are both soluble in nitric acid solution with the concentration of 20-30wt%, so that impurity elements are further removed; and then, amino active groups are further grafted on the surface of the silicon nitride, so that active free radicals are generated, and methyl methacrylate is grafted, so that the dispersion performance of the silicon nitride is improved.
Drawings
The accompanying drawings are included to provide a further understanding of the invention and are incorporated in and constitute a part of this specification, illustrate the invention and together with the embodiments of the invention, serve to explain the invention. In the drawings:
FIG. 1 is a graph showing the particle size distribution of silicon nitride powder prepared in example 1 of the present invention;
FIG. 2 is a graph showing the particle size distribution of silicon nitride powder prepared in example 2 of the present invention;
FIG. 3 is a graph showing the particle size distribution of silicon nitride powder prepared in example 3 of the present invention;
FIG. 4 is a graph showing the particle size distribution of silicon nitride powder prepared in example 4 of the present invention;
FIG. 5 is a graph showing the particle size distribution of silicon nitride powder prepared in example 5 of the present invention;
FIG. 6 is a graph showing the particle size distribution of silicon nitride powder prepared in example 6 of the present invention;
FIG. 7 is a graph showing the particle size distribution of the silicon nitride powder prepared in example 7 of the present invention.
Detailed Description
The following description of the embodiments of the present invention will be made clearly and completely with reference to the accompanying drawings, in which it is apparent that the embodiments described are only some embodiments of the present invention, but not all embodiments. All other embodiments, which can be made by those skilled in the art based on the embodiments of the invention without making any inventive effort, are intended to be within the scope of the invention.
In the examples and comparative examples of the present invention, bis (4-aminophenoxy) dimethylsilane was obtained from Zhengzhou Ling Co., ltd; the methyl methacrylate is purchased from Shandong chemical industry Co., ltd;
example 1.
The synthesis of the silicon nitride powder comprises the following steps:
s1, in a nitrogen atmosphere, 10kg of silicon powder and 3kg of Si are added 3 N 4 Mixing the powder, 0.1kg of zirconia, 0.1kg of zirconium nitride, 0.15kg of magnesium nitride and 3kg of NaCl, and ball milling for 3 hours to obtain a mixed raw material;
wherein during ball milling, the ball-material ratio in the ball mill is 3:1, the particle size of the grinding ball is 5mm, and the ball milling rotating speed is 450rpm;
s2, heating the mixed raw materials in a hydrogen atmosphere, heating to 1300 ℃ at a speed of 3 ℃/min, switching to a hydrogen-nitrogen mixed atmosphere, wherein the volume ratio of nitrogen to hydrogen is 92:8, continuing to keep the temperature, and after nitriding for 3 hours, stopping heating, and cooling to room temperature along with a furnace to obtain a nitriding product;
in the heating process, the reaction air pressure changes along with the temperature, the reaction air pressure is 0.5MPa when the temperature is 25-900 ℃, the reaction air pressure is 2MPa when the temperature is raised to 900-1200 ℃, the reaction air pressure is 1MPa when the temperature is raised to 1200-1250 ℃, the air pressure is 0.2MPa when the temperature is raised to 1250-1300 ℃, and the air pressure is kept until the nitriding reaction is finished;
s3, dispersing the nitriding product prepared in the step S2 into a nitric acid solution with the concentration of 20wt%, performing ultrasonic dispersion for 3 hours, performing centrifugal separation, washing the precipitate to be neutral by using ultrapure water, and drying for 6 hours at the vacuum temperature of 80 ℃;
s4, weighing 10kg of the nitrided product treated in the step S3, dispersing the nitrided product into 20kg of acetone, dropwise adding 0.5kg of bis (4-aminophenoxy) dimethylsilane, heating to 45 ℃, carrying out ultrasonic vibration treatment for 1h at the frequency of 20KHz, centrifugally separating the nitrided product, washing 2 times by using acetone, and drying to constant weight at the vacuum temperature of 80 ℃ to obtain an amino modified nitrided product;
s5, weighing 10kg of amino modified nitriding product, dispersing into a mixed solution of 20kg of N, N-dimethylformamide and 3kg of diethylamine, dispersing by ultrasonic waves with the frequency of 20KHz for 1h, adding 0.5kg of trichloroacetyl chloride, carrying out reflux reaction for 6h, centrifuging, washing for 3 times by using acetone, and drying at the temperature of 80 ℃ in vacuum until the weight is constant to obtain an active nitriding product;
s6, weighing 10kg of active nitriding product and 0.5kg of methyl methacrylate, adding into 15kg of N, N-dimethylformamide, heating to 50 ℃ under the protection of nitrogen atmosphere, reacting for 4 hours, centrifugally separating, washing for 5 times by using acetone, and drying for 12 hours at the temperature of 80 ℃ in vacuum to obtain the silicon nitride powder.
Example 2.
The synthesis of the silicon nitride powder comprises the following steps:
s1, in a nitrogen atmosphere, 10kg of silicon powder and 3kg of Si are mixed 3 N 4 Mixing the powder, 0.25kg of zirconia, 0.25kg of zirconium nitride, 0.15kg of ferric oxide and 3kg of NaCl, and ball milling for 6 hours to obtain a mixed raw material;
wherein during ball milling, the ball-material ratio in the ball mill is 3:1, the particle size of the grinding ball is 5mm, and the ball milling rotating speed is 500rpm;
s2, heating the mixed raw materials in a hydrogen atmosphere, heating to 1300 ℃ at a speed of 3 ℃/min, switching to a hydrogen-nitrogen mixed atmosphere, wherein the volume ratio of nitrogen to hydrogen is 92:8, continuing to keep the temperature, and after nitriding for 3 hours, stopping heating, and cooling to room temperature along with a furnace to obtain a nitriding product;
in the heating process, the reaction air pressure changes along with the temperature, the reaction air pressure is 0.5MPa when the temperature is 25-900 ℃, the reaction air pressure is 2MPa when the temperature is raised to 900-1200 ℃, the reaction air pressure is 1MPa when the temperature is raised to 1200-1250 ℃, the air pressure is 0.2MPa when the temperature is raised to 1250-1300 ℃, and the air pressure is kept until the nitriding reaction is finished;
s3, dispersing the nitriding product prepared in the step S2 into a nitric acid solution with the concentration of 20wt%, performing ultrasonic dispersion for 3 hours, performing centrifugal separation, washing the precipitate to be neutral by using ultrapure water, and drying for 6 hours at the vacuum temperature of 80 ℃;
s4, weighing 10kg of the nitrided product treated in the step S3, dispersing the nitrided product into 20kg of acetone, dropwise adding 0.5kg of bis (4-aminophenoxy) dimethylsilane, heating to 45 ℃, carrying out ultrasonic vibration treatment for 1h at the frequency of 20KHz, centrifugally separating the nitrided product, washing 2 times by using acetone, and drying to constant weight at the vacuum temperature of 80 ℃ to obtain an amino modified nitrided product;
s5, weighing 10kg of amino modified nitriding product, dispersing into a mixed solution of 20kg of N, N-dimethylformamide and 3kg of diethylamine, dispersing by ultrasonic waves with the frequency of 20KHz for 1h, adding 0.5kg of trichloroacetyl chloride, carrying out reflux reaction for 6h, centrifuging, washing for 3 times by using acetone, and drying at the temperature of 80 ℃ in vacuum until the weight is constant to obtain an active nitriding product;
s6, weighing 10kg of active nitriding product and 0.5kg of methyl methacrylate, adding into 15kg of N, N-dimethylformamide, heating to 50 ℃ under the protection of nitrogen atmosphere, reacting for 4 hours, centrifugally separating, washing for 5 times by using acetone, and drying for 12 hours at the temperature of 80 ℃ in vacuum to obtain the silicon nitride powder.
Example 3.
The synthesis of the silicon nitride powder comprises the following steps:
s1, in a nitrogen atmosphere, 10kg of silicon powder and 4kg of Si are mixed 3 N 4 Mixing the powder, 0.2kg of zirconia, 0.25kg of zirconium nitride, 0.25kg of magnesium nitride and 3kg of NaCl, and ball milling for 5 hours to obtain a mixed raw material;
wherein during ball milling, the ball-material ratio in the ball mill is 3:1, the particle size of the grinding ball is 5mm, and the ball milling rotating speed is 550rpm;
s2, heating the mixed raw materials in a hydrogen atmosphere, heating to 1400 ℃ at a speed of 3 ℃/min, and switching to a hydrogen-nitrogen mixed atmosphere, wherein the volume ratio of nitrogen to hydrogen is 92:8, stopping heating after nitriding for 3 hours, and cooling to room temperature along with a furnace to obtain a nitriding product;
in the heating process, the reaction air pressure changes along with the temperature, the reaction air pressure is 0.5MPa when the temperature is 25-900 ℃, the reaction air pressure is 1.8MPa when the temperature is raised to 900-1200 ℃, the reaction air pressure is 1MPa when the temperature is raised to 1200-1250 ℃, the air pressure is 0.2MPa when the temperature is raised to 1250-1400 ℃, and the air pressure is kept until the nitriding reaction is finished;
s3, dispersing the nitriding product prepared in the step S2 into a nitric acid solution with the concentration of 20wt%, performing ultrasonic dispersion for 3 hours, performing centrifugal separation, washing the precipitate to be neutral by using ultrapure water, and drying for 6 hours at the vacuum temperature of 80 ℃;
s4, weighing 10kg of the nitrided product treated in the step S3, dispersing the nitrided product into 20kg of acetone, dropwise adding 0.5kg of bis (4-aminophenoxy) dimethylsilane, heating to 45 ℃, carrying out ultrasonic vibration treatment for 1h at the frequency of 20KHz, centrifugally separating the nitrided product, washing 2 times by using acetone, and drying to constant weight at the vacuum temperature of 80 ℃ to obtain an amino modified nitrided product;
s5, weighing 10kg of amino modified nitriding product, dispersing into a mixed solution of 20kg of N, N-dimethylformamide and 3kg of diethylamine, dispersing by ultrasonic waves with the frequency of 20KHz for 1h, adding 0.5kg of trichloroacetyl chloride, carrying out reflux reaction for 6h, centrifuging, washing for 3 times by using acetone, and drying at the temperature of 80 ℃ in vacuum until the weight is constant to obtain an active nitriding product;
s6, weighing 10kg of active nitriding product and 0.5kg of methyl methacrylate, adding into 15kg of N, N-dimethylformamide, heating to 50 ℃ under the protection of nitrogen atmosphere, reacting for 4 hours, centrifugally separating, washing for 5 times by using acetone, and drying for 12 hours at the temperature of 80 ℃ in vacuum to obtain the silicon nitride powder.
Example 4.
The synthesis of the silicon nitride powder comprises the following steps:
s1, in a nitrogen atmosphere, 10kg of silicon powder and 5kg of Si are mixed 3 N 4 Mixing the powder, 0.2kg of zirconia, 0.25kg of zirconium nitride, 0.25kg of titanium dioxide and 3kg of NaCl, and ball milling for 5 hours to obtain a mixed raw material;
wherein during ball milling, the ball-material ratio in the ball mill is 3:1, the particle size of the grinding ball is 5mm, and the ball milling rotating speed is 550rpm;
s2, heating the mixed raw materials in a hydrogen atmosphere, heating to 1350 ℃ at a speed of 5 ℃/min, switching to a hydrogen-nitrogen mixed atmosphere, wherein the volume ratio of nitrogen to hydrogen is 92:8, continuing to keep the temperature, and after nitriding for 4 hours, stopping heating, and cooling to room temperature along with a furnace to obtain a nitriding product;
in the heating process, the reaction air pressure changes along with the temperature, the reaction air pressure is 0.5MPa when the temperature is 25-900 ℃, the reaction air pressure is 2MPa when the temperature is raised to 900-1200 ℃, the reaction air pressure is 1MPa when the temperature is raised to 1200-1250 ℃, the air pressure is 0.2MPa when the temperature is raised to 1250-1300 ℃, and the air pressure is kept until the nitriding reaction is finished;
s3, dispersing the nitriding product prepared in the step S2 into a nitric acid solution with the concentration of 20wt%, performing ultrasonic dispersion for 3 hours, performing centrifugal separation, washing the precipitate to be neutral by using ultrapure water, and drying for 6 hours at the vacuum temperature of 80 ℃;
s4, weighing 10kg of the nitrided product treated in the step S3, dispersing the nitrided product into 20kg of acetone, dropwise adding 0.5kg of bis (4-aminophenoxy) dimethylsilane, heating to 45 ℃, carrying out ultrasonic vibration treatment for 1h at the frequency of 20KHz, centrifugally separating the nitrided product, washing 2 times by using acetone, and drying to constant weight at the vacuum temperature of 80 ℃ to obtain an amino modified nitrided product;
s5, weighing 10kg of amino modified nitriding product, dispersing into a mixed solution of 20kg of N, N-dimethylformamide and 3kg of diethylamine, dispersing by ultrasonic waves with the frequency of 20KHz for 1h, adding 0.5kg of trichloroacetyl chloride, carrying out reflux reaction for 6h, centrifuging, washing for 3 times by using acetone, and drying at the temperature of 80 ℃ in vacuum until the weight is constant to obtain an active nitriding product;
s6, weighing 10kg of active nitriding product and 0.5kg of methyl methacrylate, adding into 15kg of N, N-dimethylformamide, heating to 50 ℃ under the protection of nitrogen atmosphere, reacting for 4 hours, centrifugally separating, washing for 5 times by using acetone, and drying for 12 hours at the temperature of 80 ℃ in vacuum to obtain the silicon nitride powder.
Example 5.
The synthesis of the silicon nitride powder comprises the following steps:
s1, in a nitrogen atmosphere, 10kg of silicon powder and 5kg of Si are mixed 3 N 4 Mixing the powder, 0.3kg of zirconia, 0.4kg of zirconium nitride, 0.5kg of magnesium nitride and 5kg of NaCl, and ball milling for 6 hours to obtain a mixed raw material;
wherein during ball milling, the ball-material ratio in the ball mill is 3:1, the particle size of the grinding ball is 5mm, and the ball milling rotating speed is 600rpm;
s2, heating the mixed raw materials in a hydrogen atmosphere, heating to 1450 ℃ at a speed of 5 ℃/min, switching to a hydrogen-nitrogen mixed atmosphere, wherein the volume ratio of nitrogen to hydrogen is 92:8, continuing to keep the temperature, and after nitriding for 6 hours, stopping heating, and cooling to room temperature along with a furnace to obtain a nitriding product;
in the heating process, the reaction air pressure changes along with the temperature, the reaction air pressure is 0.5MPa when the temperature is 25-900 ℃, the reaction air pressure is 2MPa when the temperature is raised to 900-1200 ℃, the reaction air pressure is 1MPa when the temperature is raised to 1200-1250 ℃, the air pressure is 0.2MPa when the temperature is raised to 1250-1450 ℃, and the air pressure is kept until the nitriding reaction is finished;
s3, dispersing the nitriding product prepared in the step S2 into a nitric acid solution with the concentration of 20wt%, performing ultrasonic dispersion for 4 hours, performing centrifugal separation, washing the precipitate to be neutral by using ultrapure water, and drying for 8 hours at the vacuum temperature of 80 ℃;
s4, weighing 10kg of the nitrided product treated in the step S3, dispersing the nitrided product into 20kg of acetone, dropwise adding 1.5kg of bis (4-aminophenoxy) dimethylsilane, heating to 60 ℃, carrying out ultrasonic vibration treatment for 4 hours at the frequency of 20KHz, centrifugally separating the nitrided product, washing 2 times by using acetone, and drying to constant weight at the vacuum temperature of 80 ℃ to obtain an amino modified nitrided product;
s5, weighing 10kg of amino modified nitriding product, dispersing into a mixed solution of 20kg of N, N-dimethylformamide and 4.5kg of diethylamine, dispersing by ultrasonic waves with the frequency of 20KHz for 2 hours, adding 1.5kg of trichloroacetyl chloride, carrying out reflux reaction for 6 hours, centrifuging, washing for 3 times by using acetone, and drying to constant weight at the temperature of 80 ℃ in vacuum to obtain an active nitriding product;
s6, weighing 10kg of active nitriding product and 1.5kg of methyl methacrylate, adding into 15kg of N, N-dimethylformamide, heating to 50 ℃ under the protection of nitrogen atmosphere, reacting for 4 hours, centrifugally separating, washing for 5 times by using acetone, and drying for 12 hours at the temperature of 80 ℃ in vacuum to obtain the silicon nitride powder.
Comparative example 1:
compared with example 1, the comparative example adopts the conventional silicon nitride powder synthesis technology, and comprises the following steps:
s1, uniformly mixing 10kg of silicon powder, 5kg of Si3N4 powder, 0.3kg of ferric oxide and 0.2kg of magnesium nitride;
s2, placing the mixed raw materials into a furnace, heating to 1350 ℃ at a speed of 5 ℃/min under a nitrogen atmosphere, preserving heat for 6 hours, stopping heating after nitriding reaction, and cooling to room temperature along with the furnace to obtain a nitriding product;
s3, washing the nitriding product with acetone for 5 times, and drying at the temperature of 80 ℃ in vacuum for 12 hours to obtain the silicon nitride powder.
And (3) detection: the particle size distribution of the samples of examples 1-6 and comparative example 1 was measured by a laser diffraction method, the measurement results are shown in fig. 1-7, the alpha phase ratio thereof was measured by an X-ray diffraction method, and the measurement results are shown in table 1;
it is noted that relational terms such as first and second, and the like are used solely to distinguish one entity or action from another entity or action without necessarily requiring or implying any actual such relationship or order between such entities or actions. Moreover, the terms "comprises," "comprising," or any other variation thereof, are intended to cover a non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements does not include only those elements but may include other elements not expressly listed or inherent to such process, method, article, or apparatus.
Finally, it should be noted that: the foregoing description is only a preferred embodiment of the present invention, and the present invention is not limited thereto, but it is to be understood that modifications and equivalents of some of the technical features described in the foregoing embodiments may be made by those skilled in the art, although the present invention has been described in detail with reference to the foregoing embodiments. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present invention should be included in the protection scope of the present invention.
Claims (10)
1. The synthesis method of the silicon nitride powder is characterized by comprising the following steps of:
s1, mixing silicon powder, a diluent, a catalyst and NaCl in a nitrogen atmosphere, and ball-milling for 3-6 hours to obtain a mixed raw material;
s2, heating the mixed raw materials in a hydrogen atmosphere, heating to a nitriding temperature at a speed of 3-5 ℃/min, switching to a hydrogen-nitrogen mixed atmosphere, continuing to keep the temperature, stopping heating after nitriding for 3-6 hours, and cooling to room temperature along with a furnace to obtain a nitriding product;
s3, dispersing the nitriding product into a nitric acid solution with the concentration of 20-30wt%, performing ultrasonic dispersion for 3-4 hours, performing centrifugal separation, washing the precipitate to be neutral by using ultrapure water, and performing vacuum drying for 6-8 hours;
s4, dispersing the nitrided product treated in the step S3 into acetone, dropwise adding bis (4-aminophenoxy) dimethylsilane, heating to 45-60 ℃, carrying out ultrasonic vibration treatment for 1-4 hours, centrifugally separating the nitrided product, washing 2-3 times by using acetone, and carrying out vacuum drying until the weight is constant to obtain an amino-modified nitrided product;
s5, dispersing the amino-modified nitridation product into a mixed solution of N, N-dimethylformamide and diethylamine, ultrasonically dispersing for 1-2 hours, adding trichloroacetyl chloride, carrying out reflux reaction for 6-8 hours, carrying out centrifugal separation, washing for 3-5 times by using acetone, and carrying out vacuum drying to constant weight to obtain an active nitridation product;
s6, adding the active nitriding product and methyl methacrylate into N, N-dimethylformamide, protecting in nitrogen atmosphere, heating to 50-65 ℃, reacting for 4-8 hours, centrifugally separating, washing for 5-8 times by using acetone, and drying in vacuum to obtain silicon nitride powder.
2. A method of synthesizing silicon nitride powder according to claim 1, wherein: in the step S1, the mass ratio of the silicon powder, the diluent, the catalyst and NaCl is 10: (3-5): (0.35-1.2): (3-5).
3. A method of synthesizing silicon nitride powder according to claim 1, wherein: the catalyst consists of zirconium oxide, zirconium nitride and other metal compounds;
wherein, the mass ratio of the zirconia, the zirconium nitride and other metal compounds is (0.1-0.3) according to the weight parts: (0.1-0.4): (0.15-0.5).
4. A method of synthesizing silicon nitride powder according to claim 3, wherein: the diluent is Si 3 N 4 Powder; the metal compound is Fe 2 O 3 、TiO 2 、3Y-ZrO 2 、MgO、MgSiN 2 Any one or more of MgN.
5. A method of synthesizing silicon nitride powder according to claim 1, wherein: during ball milling, the ball-material ratio in the ball mill is 3:1, the grain diameter of the grinding balls is 3-6mm, and the ball milling rotating speed is 450-600rpm.
6. A method of synthesizing silicon nitride powder according to claim 1, wherein: in the step S2, the nitriding temperature is 1300-1450 ℃;
wherein when heating, the temperature is raised to 25-900 ℃, and the reaction air pressure is 0.4-0.6MPa; when the temperature is raised to 900-1200 ℃, the air pressure is 2-3MPa; when the temperature is raised to 1200-1250 ℃, the air pressure is reduced to 1-1.5MPa, and when the temperature is raised to 1250-1450 ℃, the air pressure is 0.2-0.3MPa.
7. A method of synthesizing silicon nitride powder according to claim 1, wherein: in the step S2, in the hydrogen-nitrogen mixing atmosphere, the volume ratio of nitrogen to hydrogen is (88-92) according to the volume parts: (8-12).
8. A method of synthesizing silicon nitride powder according to claim 1, wherein: in the step S4, the mass ratio of the nitriding product to the bis (4-aminophenoxy) dimethylsilane is 10: (0.5-1.5).
9. A method of synthesizing silicon nitride powder according to claim 1, wherein: in the step S5, the mass ratio of the amino modified nitridation product to diethylamine to trichloroacetyl chloride is 10: (3-4.5): (0.5-1.5).
10. A method of synthesizing silicon nitride powder according to claim 1, wherein: in the step S6, the mass ratio of the active nitriding product to the methyl methacrylate is 10: (0.5-1.5).
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| US5441694A (en) * | 1993-06-11 | 1995-08-15 | Shin-Etsu Chemical Co., Ltd. | Preparation of high α-type silicon nitride powder |
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| JP2012180235A (en) * | 2011-02-28 | 2012-09-20 | Kubota Corp | Method for producing silicon nitride-based ceramic |
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