CN115637063A - Coating modification method of aluminum nitride powder and application thereof - Google Patents
Coating modification method of aluminum nitride powder and application thereof Download PDFInfo
- Publication number
- CN115637063A CN115637063A CN202211070665.0A CN202211070665A CN115637063A CN 115637063 A CN115637063 A CN 115637063A CN 202211070665 A CN202211070665 A CN 202211070665A CN 115637063 A CN115637063 A CN 115637063A
- Authority
- CN
- China
- Prior art keywords
- aluminum nitride
- nitride powder
- coating agent
- powder
- coating
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Granted
Links
- 239000000843 powder Substances 0.000 title claims abstract description 446
- PMHQVHHXPFUNSP-UHFFFAOYSA-M copper(1+);methylsulfanylmethane;bromide Chemical compound Br[Cu].CSC PMHQVHHXPFUNSP-UHFFFAOYSA-M 0.000 title claims abstract description 318
- 239000011248 coating agent Substances 0.000 title claims abstract description 291
- 238000000576 coating method Methods 0.000 title claims abstract description 77
- 238000002715 modification method Methods 0.000 title claims abstract description 21
- 238000000034 method Methods 0.000 claims abstract description 88
- 239000000463 material Substances 0.000 claims abstract description 51
- 239000002245 particle Substances 0.000 claims abstract description 38
- 239000000945 filler Substances 0.000 claims abstract description 36
- 238000012986 modification Methods 0.000 claims abstract description 34
- 230000004048 modification Effects 0.000 claims abstract description 34
- 238000002156 mixing Methods 0.000 claims description 133
- 238000005507 spraying Methods 0.000 claims description 81
- 239000003085 diluting agent Substances 0.000 claims description 69
- 238000001035 drying Methods 0.000 claims description 59
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 claims description 52
- 238000011049 filling Methods 0.000 claims description 42
- 239000002904 solvent Substances 0.000 claims description 41
- 230000033001 locomotion Effects 0.000 claims description 32
- LFQSCWFLJHTTHZ-UHFFFAOYSA-N Ethanol Chemical compound CCO LFQSCWFLJHTTHZ-UHFFFAOYSA-N 0.000 claims description 27
- 239000007788 liquid Substances 0.000 claims description 27
- 238000006243 chemical reaction Methods 0.000 claims description 25
- QVGXLLKOCUKJST-UHFFFAOYSA-N atomic oxygen Chemical compound [O] QVGXLLKOCUKJST-UHFFFAOYSA-N 0.000 claims description 18
- 239000001301 oxygen Substances 0.000 claims description 18
- 229910052760 oxygen Inorganic materials 0.000 claims description 18
- OKTJSMMVPCPJKN-UHFFFAOYSA-N Carbon Chemical compound [C] OKTJSMMVPCPJKN-UHFFFAOYSA-N 0.000 claims description 17
- 229910052799 carbon Inorganic materials 0.000 claims description 17
- BLRPTPMANUNPDV-UHFFFAOYSA-N Silane Chemical group [SiH4] BLRPTPMANUNPDV-UHFFFAOYSA-N 0.000 claims description 12
- 229910000077 silane Inorganic materials 0.000 claims description 12
- 125000003545 alkoxy group Chemical group 0.000 claims description 8
- 239000003209 petroleum derivative Substances 0.000 claims description 8
- 150000003961 organosilicon compounds Chemical class 0.000 claims description 7
- 239000011247 coating layer Substances 0.000 abstract description 16
- 230000001105 regulatory effect Effects 0.000 abstract description 6
- 239000004519 grease Substances 0.000 abstract description 3
- 229920001296 polysiloxane Polymers 0.000 abstract description 3
- 229920002545 silicone oil Polymers 0.000 description 30
- 125000000391 vinyl group Chemical group [H]C([*])=C([H])[H] 0.000 description 22
- 229920002554 vinyl polymer Polymers 0.000 description 18
- 239000000203 mixture Substances 0.000 description 16
- PNEYBMLMFCGWSK-UHFFFAOYSA-N aluminium oxide Inorganic materials [O-2].[O-2].[O-2].[Al+3].[Al+3] PNEYBMLMFCGWSK-UHFFFAOYSA-N 0.000 description 12
- 239000003054 catalyst Substances 0.000 description 12
- UFHFLCQGNIYNRP-UHFFFAOYSA-N Hydrogen Chemical compound [H][H] UFHFLCQGNIYNRP-UHFFFAOYSA-N 0.000 description 11
- 239000001257 hydrogen Substances 0.000 description 11
- 229910052739 hydrogen Inorganic materials 0.000 description 11
- 230000001276 controlling effect Effects 0.000 description 9
- 235000019441 ethanol Nutrition 0.000 description 9
- -1 alkyl triethoxysilane Chemical compound 0.000 description 8
- 239000003607 modifier Substances 0.000 description 7
- 239000011231 conductive filler Substances 0.000 description 6
- 238000001125 extrusion Methods 0.000 description 6
- 239000003795 chemical substances by application Substances 0.000 description 5
- 230000007547 defect Effects 0.000 description 4
- 239000000758 substrate Substances 0.000 description 4
- 230000000052 comparative effect Effects 0.000 description 3
- 238000004108 freeze drying Methods 0.000 description 3
- 238000002347 injection Methods 0.000 description 3
- 239000007924 injection Substances 0.000 description 3
- 229920001558 organosilicon polymer Polymers 0.000 description 3
- 238000002360 preparation method Methods 0.000 description 3
- 239000002994 raw material Substances 0.000 description 3
- 238000001694 spray drying Methods 0.000 description 3
- 238000003860 storage Methods 0.000 description 3
- 238000001291 vacuum drying Methods 0.000 description 3
- QGZKDVFQNNGYKY-UHFFFAOYSA-N Ammonia Chemical compound N QGZKDVFQNNGYKY-UHFFFAOYSA-N 0.000 description 2
- IJGRMHOSHXDMSA-UHFFFAOYSA-N Atomic nitrogen Chemical compound N#N IJGRMHOSHXDMSA-UHFFFAOYSA-N 0.000 description 2
- CPLXHLVBOLITMK-UHFFFAOYSA-N Magnesium oxide Chemical compound [Mg]=O CPLXHLVBOLITMK-UHFFFAOYSA-N 0.000 description 2
- XLOMVQKBTHCTTD-UHFFFAOYSA-N Zinc monoxide Chemical compound [Zn]=O XLOMVQKBTHCTTD-UHFFFAOYSA-N 0.000 description 2
- 239000000853 adhesive Substances 0.000 description 2
- 230000001070 adhesive effect Effects 0.000 description 2
- 230000032683 aging Effects 0.000 description 2
- XAGFODPZIPBFFR-UHFFFAOYSA-N aluminium Chemical compound [Al] XAGFODPZIPBFFR-UHFFFAOYSA-N 0.000 description 2
- 230000002238 attenuated effect Effects 0.000 description 2
- 238000005034 decoration Methods 0.000 description 2
- 239000006185 dispersion Substances 0.000 description 2
- 125000002887 hydroxy group Chemical group [H]O* 0.000 description 2
- 230000003068 static effect Effects 0.000 description 2
- 239000006087 Silane Coupling Agent Substances 0.000 description 1
- XUIMIQQOPSSXEZ-UHFFFAOYSA-N Silicon Chemical compound [Si] XUIMIQQOPSSXEZ-UHFFFAOYSA-N 0.000 description 1
- 235000021355 Stearic acid Nutrition 0.000 description 1
- RTAQQCXQSZGOHL-UHFFFAOYSA-N Titanium Chemical compound [Ti] RTAQQCXQSZGOHL-UHFFFAOYSA-N 0.000 description 1
- WNROFYMDJYEPJX-UHFFFAOYSA-K aluminium hydroxide Chemical compound [OH-].[OH-].[OH-].[Al+3] WNROFYMDJYEPJX-UHFFFAOYSA-K 0.000 description 1
- 229910021529 ammonia Inorganic materials 0.000 description 1
- 230000005540 biological transmission Effects 0.000 description 1
- 238000005253 cladding Methods 0.000 description 1
- 238000004891 communication Methods 0.000 description 1
- 238000013329 compounding Methods 0.000 description 1
- 238000010276 construction Methods 0.000 description 1
- 125000000118 dimethyl group Chemical group [H]C([H])([H])* 0.000 description 1
- 238000005516 engineering process Methods 0.000 description 1
- 239000007789 gas Substances 0.000 description 1
- 230000017525 heat dissipation Effects 0.000 description 1
- 230000007062 hydrolysis Effects 0.000 description 1
- 238000006460 hydrolysis reaction Methods 0.000 description 1
- 230000010354 integration Effects 0.000 description 1
- 239000010410 layer Substances 0.000 description 1
- 239000000395 magnesium oxide Substances 0.000 description 1
- 238000004519 manufacturing process Methods 0.000 description 1
- 239000011159 matrix material Substances 0.000 description 1
- 238000005121 nitriding Methods 0.000 description 1
- 229910052757 nitrogen Inorganic materials 0.000 description 1
- QIQXTHQIDYTFRH-UHFFFAOYSA-N octadecanoic acid Chemical compound CCCCCCCCCCCCCCCCCC(O)=O QIQXTHQIDYTFRH-UHFFFAOYSA-N 0.000 description 1
- OQCDKBAXFALNLD-UHFFFAOYSA-N octadecanoic acid Natural products CCCCCCCC(C)CCCCCCCCC(O)=O OQCDKBAXFALNLD-UHFFFAOYSA-N 0.000 description 1
- 238000012856 packing Methods 0.000 description 1
- 125000001997 phenyl group Chemical group [H]C1=C([H])C([H])=C(*)C([H])=C1[H] 0.000 description 1
- 229920000642 polymer Polymers 0.000 description 1
- 238000011160 research Methods 0.000 description 1
- 229910052710 silicon Inorganic materials 0.000 description 1
- 239000010703 silicon Substances 0.000 description 1
- 150000003377 silicon compounds Chemical class 0.000 description 1
- 229920005573 silicon-containing polymer Polymers 0.000 description 1
- 239000002002 slurry Substances 0.000 description 1
- 239000000243 solution Substances 0.000 description 1
- 238000001179 sorption measurement Methods 0.000 description 1
- 239000007921 spray Substances 0.000 description 1
- 239000008117 stearic acid Substances 0.000 description 1
- 239000000126 substance Substances 0.000 description 1
- 238000012546 transfer Methods 0.000 description 1
- 239000011787 zinc oxide Substances 0.000 description 1
Landscapes
- Ceramic Products (AREA)
- Glanulating (AREA)
Abstract
The invention belongs to the field of heat-conducting fillers, and particularly relates to a coating modification method of aluminum nitride powder and application thereof. The coating modification method provided by the invention is according to D 50 Difference in particle diameter of D 50 Aluminum nitride powder with particle size less than 2 mu m and D 50 Aluminum nitride powder having particle diameter of 2 to 10 μm, and D 50 The aluminum nitride powder with the grain diameter larger than 10 mu m is subjected to differential coating modification. According to the method, the aluminum nitride powder is subjected to graded differential fine coating modification treatment, and the coating layer of the aluminum nitride powder can be accurately regulated and controlled, so that the finally obtained modified aluminum nitride can have effective coating grafting rate, coating layer thickness and D meeting expected requirements 50 Particle size and surface energy. Experimental results show that the modified aluminum nitride prepared by the method has excellent properties, and can be used as a filler for high heat conduction and high stabilityPreparation of qualitative and low-viscosity thermal interface materials (such as heat-conducting gel and heat-conducting silicone grease).
Description
Technical Field
The invention belongs to the field of heat-conducting fillers, and particularly relates to a coating modification method of aluminum nitride powder and application thereof.
Background
With the trend of miniaturization and integration of electronic components, the industry needs to solve the heat dissipation problem in order to ensure the stability, reliability and durability of the electronic components. Due to the manufacturing process, a large number of air holes are generated after the rough surface contact between the heat source and the heat sink, and the heat transmission is seriously hindered because the air thermal conductivity is too low. In order to solve this problem, a thermal interface filling material has been proposed to replace the original air gap, and the thermal conductivity and heat transfer efficiency can be improved by filling an inorganic thermal conductive filler into an organic matrix. The thermal interface material is widely applied to communication base stations, new energy automobiles, consumer electronic products and the like. Aluminum nitride is attractive as a thermally conductive filler for high thermal conductivity thermal interface materials due to its isotropic high thermal conductivity. The high-thermal-conductivity thermal interface material needs to use aluminum nitride powder as a heat-conducting filler to realize more dense packing through particle size compounding, and has high filling rate, so that the product has the problems of high viscosity, poor compatibility, poor construction manufacturability, high interface thermal resistance and the like, and the industrial application of the thermal interface material is seriously hindered. These performance issues are currently being improved and optimized by the industry primarily through surface modified coating of filler aluminum nitride.
In the surface modification treatment of the heat-conducting filler powder in the prior art, certain modifying agent is utilized to enable surface hydroxyl of the powder to react with the modifying agent through a certain process method, so that the surface active hydroxyl of the powder is eliminated or reduced, and the purpose of changing the surface property is achieved. The prior art can be broadly divided into two categories: one is to use modifier to pretreat, and the modifier includes silane coupling agent, titanate, stearic acid and other liquid with small molecular weight or oligosiloxane with certain molecular weight. The research on the modification of aluminum nitride is based on the selection of the modifiers and the corresponding work of optimizing the realization process. The currently used method mainly comprises dry modification and wet modification. At present, dry modification mainly comprises the steps of adding powder and a modifier into a high-speed mixer for simple mixing, and then reacting at a certain temperature, wherein the defect of high viscosity after a thermal interface material is prepared due to incomplete coating is often caused; the wet modification needs to prepare a powder raw material into a slurry state for modification, but because the aluminum nitride powder is very easy to hydrolyze, the defect of low heat conduction caused by poor coating thickness control is often existed. The other treatment method is to use the modifiers as one component of the formula of the thermal interface material, and although a series of complicated operations are omitted, the treatment agent is mostly acted on the surface of the powder in a physical adsorption mode, only a few parts of the treatment agent react with the surface of the powder to generate chemical bonds, the modifier which does not react chemically has the defect of poor stability in a system, and the modifier is extremely easy to volatilize or self-polymerize in the aging processes of high temperature, damp heat, temperature cycle and the like, so that the thermal interface material is ineffective in the aging process.
Particularly with respect to aluminum nitride powder, the major disadvantages of aluminum nitride powder, unlike conventional thermally conductive fillers such as alumina, magnesia, zinc oxide, and the like, are that it is hydrolytically unstable, is very sensitive to contact with liquid water or water vapor, and readily decomposes to form aluminum hydroxide and ammonia, the degree of hydrolysis affecting its thermal conductivity and flowability as a filler for application to thermal interface materials. However, the surface coating modification technology of aluminum nitride powder as a filler of the existing thermal interface material is not fine and controllable enough, and generally faces the defects that the material cannot have high thermal conductivity, high stability and low viscosity at the same time, and needs to be improved and optimized.
Disclosure of Invention
In view of the above, the present invention provides a coating modification method for aluminum nitride powder and an application thereof, and the method provided by the present invention can precisely regulate and control a coating layer of aluminum nitride powder by performing graded differential fine coating modification treatment on aluminum nitride powder, so as to ensure that the finally obtained modified aluminum nitride has excellent properties, and can be used as a filler for preparing a high thermal conductivity, high stability and low viscosity thermal interface material.
The invention provides an application of coated modified aluminum nitride powder, wherein the coated modified aluminum nitride powder is used as a heat-conducting filler for preparing a thermal interface material;
the coated modified aluminum nitride powder is one or more of a coated modified aluminum nitride powder A, a coated modified aluminum nitride powder B and a coated modified aluminum nitride powder C prepared by the following method:
according to D 50 The method is characterized in that differential coating modification is carried out on aluminum nitride powder according to different particle sizes, and specifically comprises the following steps:
a) For D 50 The aluminum nitride powder with the grain diameter less than 2 mu m is coated and modified according to the following method:
dynamically mixing aluminum nitride powder and a coating agent diluent in a powder mixer, and then reacting and drying to obtain coated modified aluminum nitride powder A;
in the step a), the water content of the aluminum nitride powder is 0.1-5%; the filling coefficient of the aluminum nitride powder in the powder mixer is 50-80%; the components of the coating agent diluent comprise a coating agent and a solvent; the mass ratio of the coating agent to the solvent is 1: (1-5); the dosage of the cladding agent is 0.5 to 5 percent of the mass of the aluminum nitride powder; the coating agent diluent is sprayed into the powder mixer in a spraying mode to participate in dynamic mixing; in the spraying process, the diameter of the atomized liquid drop is 1-30 mu m; in the dynamic mixing process, the maximum movement speed of the aluminum nitride powder is 10-60 m/s;
b) For D 50 The aluminum nitride powder with the grain diameter of 2-10 mu m is coated and modified according to the following method:
dynamically mixing aluminum nitride powder and a coating agent diluent in a powder mixer, and reacting and drying to obtain coated modified aluminum nitride powder B;
in the step b), the water content of the aluminum nitride powder is 0.1-3%; the filling coefficient of the aluminum nitride powder in the powder mixer is 30-70%; the components of the coating agent diluent comprise a coating agent and a solvent; the mass ratio of the coating agent to the solvent is 1: (0.5-5); the using amount of the coating agent is 0.5-4% of the mass of the aluminum nitride powder; the coating agent diluent is sprayed into the powder mixer in a spraying mode to participate in dynamic mixing; in the spraying process, the diameter of the atomized liquid drop is 1-30 mu m; in the dynamic mixing process, the maximum movement speed of the aluminum nitride powder is 5-30 m/s;
c) For D 50 Nitrogen with grain size more than 10 mu mThe aluminum powder is coated and modified according to the following method:
dynamically mixing aluminum nitride powder and a coating agent diluent in a powder mixer, and then reacting and drying to obtain coated modified aluminum nitride powder C;
in the step c), the water content of the aluminum nitride powder is 0.05-3%; the filling coefficient of the aluminum nitride powder in the powder mixer is 20-60%; the components of the coating agent diluent comprise a coating agent and a solvent; the mass ratio of the coating agent to the solvent is 1: (0.5-5); the using amount of the coating agent is 0.5 to 3 percent of the mass of the aluminum nitride powder; spraying the diluent of the coating agent into a powder mixer in a spraying mode to participate in dynamic mixing; in the spraying process, the diameter of the atomized liquid drop is 1-30 mu m; in the dynamic mixing process, the maximum movement speed of the aluminum nitride powder is 2-15 m/s.
Preferably, the coated modified aluminum nitride powder is compounded with other heat-conducting fillers to be used as the heat-conducting filler for preparing the thermal interface material.
The invention also provides a coating modification method of the aluminum nitride powder according to D 50 The method for performing differential coating modification on aluminum nitride powder according to different particle sizes specifically comprises the following steps:
a) For D 50 The aluminum nitride powder with the grain diameter less than 2 mu m is coated and modified according to the following method:
dynamically mixing aluminum nitride powder and a coating agent diluent in a powder mixer, and reacting and drying to obtain coated modified aluminum nitride powder A;
in the step a), the water content of the aluminum nitride powder is 0.1-5%; the filling coefficient of the aluminum nitride powder in the powder mixer is 50-80%; the components of the coating agent diluent comprise a coating agent and a solvent; the mass ratio of the coating agent to the solvent is 1: (1-5); the using amount of the coating agent is 0.5-5% of the mass of the aluminum nitride powder; the coating agent diluent is sprayed into the powder mixer in a spraying mode to participate in dynamic mixing; in the spraying process, the diameter of the atomized liquid drop is 1-30 mu m; in the dynamic mixing process, the maximum movement speed of the aluminum nitride powder is 10-60 m/s;
b) For D 50 The aluminum nitride powder with the grain diameter of 2-10 mu m is coated and modified according to the following method:
dynamically mixing aluminum nitride powder and a coating agent diluent in a powder mixer, and then reacting and drying to obtain coated modified aluminum nitride powder B;
in the step b), the water content of the aluminum nitride powder is 0.1-3%; the filling coefficient of the aluminum nitride powder in the powder mixer is 30-70%; the components of the coating agent diluent comprise a coating agent and a solvent; the mass ratio of the coating agent to the solvent is 1: (0.5 to 5); the dosage of the coating agent is 0.5 to 4 percent of the mass of the aluminum nitride powder; spraying the diluent of the coating agent into a powder mixer in a spraying mode to participate in dynamic mixing; in the spraying process, the diameter of the atomized liquid drop is 1-30 mu m; in the dynamic mixing process, the maximum movement speed of the aluminum nitride powder is 5-30 m/s;
c) For D 50 The aluminum nitride powder with the grain diameter larger than 10 mu m is coated and modified according to the following method:
dynamically mixing aluminum nitride powder and a coating agent diluent in a powder mixer, and then reacting and drying to obtain coated modified aluminum nitride powder C;
in the step c), the water content of the aluminum nitride powder is 0.05-3%; the filling coefficient of the aluminum nitride powder in the powder mixer is 20-60%; the components of the coating agent diluent comprise a coating agent and a solvent; the mass ratio of the coating agent to the solvent is 1: (0.5-5); the using amount of the coating agent is 0.5-3% of the mass of the aluminum nitride powder; spraying the diluent of the coating agent into a powder mixer in a spraying mode to participate in dynamic mixing; in the spraying process, the diameter of the atomized liquid drop is 1-30 mu m; in the dynamic mixing process, the maximum movement speed of the aluminum nitride powder is 2-15 m/s.
Preferably, D is 50 The sphericity of the aluminum nitride powder with the grain diameter less than 2 mu m is more than or equal to 80 percent, the oxygen element content is 0.1 to 0.8 weight percent, the carbon element content is 0.01 to 0.4 weight percent, and the specific surface area is 1 to 3.2m 2 G, true density of 3.2-3.3 g/cm 3 ；
Said D 50 The sphericity of the aluminum nitride powder with the grain diameter of 2-10 mu m is more than or equal to 85 percent, the oxygen element content is 0.1-0.9 wt percent, the carbon element content is 0.01-0.4 wt percent, and the specific surface area is 0.2-1.5 m 2 G, the real density is 3.2-3.3 g/cm 3 ；
Said D 50 The sphericity of the aluminum nitride powder with the particle diameter of more than 10 mu m is more than or equal to 90 percent, the oxygen element content is 0.1 to 1 weight percent, the carbon element content is 0.01 to 0.2 weight percent, and the specific surface area is 0.01 to 0.5m 2 G, true density of 3.2-3.3 g/cm 3 。
Preferably, in steps a) to c), the coating agent is a silane oligomer and/or an alkoxy-containing organic silicon compound;
in the step a), the reaction degree of the coating agent is less than or equal to 5 percent; in the step b), the reaction degree of the coating agent is less than or equal to 10 percent; in step c), the reaction degree of the coating agent is less than or equal to 10%.
Preferably, in steps a) to c), the solvent is one or more of water, alcohol and petroleum hydrocarbon.
Preferably, in the spraying process in steps a) to c), the distance from the nozzle to the material is 10-50 cm, and the spraying angle is 30-120 degrees.
Preferably, in steps a) to c), the temperature of the dynamic mixing is 50 to 150 ℃; the time of the dynamic mixing is 1-24 h.
Preferably, in the steps a) to c), the drying temperature is 80 to 200 ℃; the drying time is 0.5-8 h.
Preferably, in the step a), the surface energy of the coated modified aluminum nitride powder A is 20-30 mJ/m 2 The effective grafting rate of the coating agent is 0.3-5%, and D is obtained before and after coating 50 The change rate of the particle diameter is less than or equal to 150 percent, and the residual rate of the unreacted coating agent is less than or equal to 2000ppm;
in the step B), the surface energy of the coated modified aluminum nitride powder B is 18-26 mJ/m 2 The effective grafting rate of the coating agent is 0.2-4%, and D is obtained before and after coating 50 The change rate of the grain diameter is less than or equal to 100 percent, and the residual rate of the unreacted coating agent is less than or equal to 2000ppm;
in the step C), the surface energy of the coated modified aluminum nitride powder C is 18-24 mJ/m 2 The effective grafting rate of the coating agent is 0.11-3%, and D is before and after coating 50 The change rate of the particle diameter is less than or equal to 30 percent, and the residual rate of the unreacted coating agent is less than or equal to 2000ppm.
Compared with the prior art, the invention provides a coating modification method of aluminum nitride powder and application thereof. The coating modification method provided by the invention is according to D 50 The different particle diameters are different, and the differential coating modification is carried out on the aluminum nitride powder, and the method specifically comprises the following steps: a) For D 50 Aluminum nitride powder with the grain diameter less than 2 mu m is coated and modified according to the following method: dynamically mixing aluminum nitride powder and a coating agent diluent in a powder mixer, and then reacting and drying to obtain coated modified aluminum nitride powder A; in the step a), the water content of the aluminum nitride powder is 0.1-5%; the filling coefficient of the aluminum nitride powder in the powder mixer is 50-80%; the components of the coating agent diluted liquid comprise a coating agent and a solvent; the mass ratio of the coating agent to the solvent is 1: (1-5); the using amount of the coating agent is 0.5-5% of the mass of the aluminum nitride powder; the coating agent diluent is sprayed into a powder mixer in a spraying mode to participate in dynamic mixing; in the spraying process, the diameter of the atomized liquid drop is 1-30 mu m; in the dynamic mixing process, the maximum movement speed of the aluminum nitride powder is 10-60 m/s; b) For D 50 The aluminum nitride powder with the grain diameter of 2-10 mu m is coated and modified according to the following method: dynamically mixing aluminum nitride powder and a coating agent diluent in a powder mixer, and reacting and drying to obtain coated modified aluminum nitride powder B; in the step b), the water content of the aluminum nitride powder is 0.1-3%; the filling coefficient of the aluminum nitride powder in the powder mixer is 30-70%; the components of the coating agent diluent comprise a coating agent and a solvent; the mass ratio of the coating agent to the solvent is 1: (0.5-5); the dosage of the coating agent is 0.5 to 4 percent of the mass of the aluminum nitride powder; the coating agent diluent is sprayed into the powder mixer in a spraying mode to participate in dynamic mixing; in the spraying process, the diameter of the atomized liquid drop is 1-30 mu m; in the dynamic mixing process, the maximum movement speed of the aluminum nitride powder is 5 to30m/s; c) For D 50 The aluminum nitride powder with the grain diameter of more than 10 mu m is coated and modified according to the following method: dynamically mixing aluminum nitride powder and a coating agent diluent in a powder mixer, and then reacting and drying to obtain coated modified aluminum nitride powder C; in the step c), the water content of the aluminum nitride powder is 0.05-3%; the filling coefficient of the aluminum nitride powder in the powder mixer is 20-60%; the components of the coating agent diluent comprise a coating agent and a solvent; the mass ratio of the coating agent to the solvent is 1: (0.5 to 5); the using amount of the coating agent is 0.5 to 3 percent of the mass of the aluminum nitride powder; the coating agent diluent is sprayed into the powder mixer in a spraying mode to participate in dynamic mixing; in the spraying process, the diameter of the atomized liquid drop is 1-30 mu m; in the dynamic mixing process, the maximum movement speed of the aluminum nitride powder is 2-15 m/s. According to the method provided by the invention, the aluminum nitride powder is subjected to graded differential fine coating modification treatment, and the coating layer of the aluminum nitride powder can be accurately regulated and controlled, so that the finally obtained modified aluminum nitride can have effective coating grafting rate, coating layer thickness and D meeting expected requirements 50 Particle size and surface energy. Experimental results show that the modified aluminum nitride prepared by the method has excellent properties, and can be used as a filler for preparing thermal interface materials (such as thermal conductive gel and thermal conductive silicone grease) with high thermal conductivity, high stability and low viscosity.
Detailed Description
The technical solutions in the embodiments of the present invention are clearly and completely described below, and it is obvious that the described embodiments are only a part of the embodiments of the present invention, and not all embodiments. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present invention.
The invention provides a coating modification method of aluminum nitride powder according to D 50 Different particle sizes are used for performing differential coating modification on aluminum nitride powder, and the method specifically comprises the following steps:
a) For D 50 The aluminum nitride powder with the grain diameter less than 2 mu m is coated and modified according to the following methodProperty:
and dynamically mixing the aluminum nitride powder and the coating agent diluent in a powder mixer, and then reacting and drying to obtain the coated modified aluminum nitride powder A.
In step a), the particle size of the aluminum nitride powder is preferably 0.5 to 2 μm (excluding the right end value of 0.2 μm), and specifically may be 0.5 μm, 0.6 μm, 0.7 μm, 0.8 μm, 0.9 μm, 1 μm, 1.1 μm, 1.2 μm, 1.3 μm, 1.4 μm, 1.5 μm, 1.6 μm, 1.7 μm, 1.8 μm or 1.9 μm.
In the step a), the sphericity of the aluminum nitride powder is preferably not less than 80%, and specifically may be 80%, 81%, 82%, 83%, 84%, 85%, 86%, 87%, 88%, 89%, 90%, 91%, 92%, 93%, 94% or 95%.
In step a), the oxygen content of the aluminum nitride powder is preferably 0.1 to 0.8wt%, and specifically may be 0.1wt%, 0.15wt%, 0.2wt%, 0.25wt%, 0.3wt%, 0.35wt%, 0.4wt%, 0.45wt%, 0.5wt%, 0.55wt%, 0.6wt%, 0.65wt%, 0.7wt%, 0.75wt%, 0.78wt%, or 0.8wt%; the carbon content of the aluminum nitride powder is preferably 0.01 to 0.4wt%, and specifically may be 0.01wt%, 0.03wt%, 0.05wt%, 0.07wt%, 0.1wt%, 0.12wt%, 0.15wt%, 0.17wt%, 0.2wt%, 0.23wt%, 0.25wt%, 0.27wt%, 0.3wt%, 0.32wt%, 0.35wt%, 0.37wt%, or 0.4wt%.
In the step a), the specific surface area of the aluminum nitride powder is preferably 1 to 3.2m 2 A specific value of 1 m/g 2 /g、 1.1m 2 /g、1.2m 2 /g、1.3m 2 /g、1.4m 2 /g、1.5m 2 /g、1.6m 2 /g、1.7m 2 /g、1.8m 2 /g、 1.9m 2 /g、2m 2 /g、2.1m 2 /g、2.2m 2 /g、2.3m 2 /g、2.4m 2 /g、2.5m 2 /g、2.6m 2 /g、2.7m 2 /g、 2.8m 2 /g、2.9m 2 /g、3m 2 /g、3.1m 2 G or 3.2m 2 /g。
In the step a), the true density of the aluminum nitride powder is preferably 3.2-3.3 g/cm 3 Specifically, it may be 3.2g/cm 3 、3.21g/cm 3 、3.22g/cm 3 、3.23g/cm 3 、3.24g/cm 3 、3.25g/cm 3 、3.26g/cm 3 、 3.27g/cm 3 、3.28g/cm 3 、3.29g/cm 3 Or 3.3g/cm 3 。
In step a), the water content of the aluminum nitride powder before mixing is 0.1-5%, specifically 0.1%, 0.3%, 0.5%, 0.7%, 1%, 1.2%, 1.5%, 1.7%, 2%, 2.3%, 2.5%, 2.7%, 3%, 3.2%, 3.5%, 3.7%, 4%, 4.2%, 4.5%, 4.7% or 5%. In the invention, the aluminum nitride powder can be placed in the dryer for a certain time, so that the water content of the aluminum nitride powder can be regulated and controlled to meet the requirement.
In step a), the filling factor of the aluminum nitride powder in the powder mixer is 50 to 80%, specifically 50%, 51%, 52%, 53%, 54%, 55%, 56%, 57%, 58%, 59%, 60%, 61%, 62%, 63%, 64%, 65%, 66%, 67%, 68%, 69%, 70%, 71%, 72%, 73%, 74%, 75%, 76%, 77%, 78%, 79% or 80%.
In the step a), the components of the coating agent diluent comprise a coating agent and a solvent; the coating agent is preferably a silane oligomer and/or an organosilicon compound containing alkoxy groups; the number average molecular weight of the silane oligomer is preferably 300 to 600, and specifically may be 300, 350, 400, 450, 500, 550 or 600; the organosilicon compound containing alkoxy is preferably long-chain alkyl triethoxysilane, more preferably C 10 Alkyltriethoxysilanes; the reaction degree of the coating agent is preferably less than or equal to 5%, and specifically can be 0.5%, 1%, 1.5%, 2%, 2.5%, 3%, 3.5%, 4%, 4.5% or 5%, and the reaction degree refers to the percentage of the mass of the coating agent material participating in the reaction to the total amount of the coating agent.
In the step a), the solvent of the coating agent diluent is preferably one or more of water, alcohol and petroleum hydrocarbon, more preferably a mixture of water and ethanol, and the mass ratio of the water to the ethanol is preferably (0.01-0.1): 2, specifically can be 0.01.
In the step a), in the coating agent diluent, the mass ratio of the coating agent to the solvent is 1: (1-5), specifically can be 1, 1.2, 1.5, 1.
In the step a), the amount of the coating agent is 0.5-5% of the aluminum nitride powder, specifically 0.5%, 0.7%, 1%, 1.2%, 1.5%, 1.7%, 2%, 2.3%, 2.5%, 2.7%, 3%, 3.2%, 3.5%, 3.7%, 4%, 4.2%, 4.5%, 4.7% or 5%.
In the step a), the diluent of the coating agent is sprayed into a powder mixer in a spray mode to participate in dynamic mixing; in the spraying process, the distance from the nozzle to the material is preferably 10-50 cm, more preferably 10-20 cm, and specifically 10cm, 11cm, 12cm, 13cm, 14cm, 15cm, 16cm, 17cm, 18cm, 19cm or 20cm; the diameter of the atomized droplets is preferably 1 to 30 μm, and may be, in particular, 1 μm, 2 μm, 3 μm, 4 μm, 5 μm, 6 μm, 7 μm, 8 μm, 9 μm, 10 μm, 11 μm, 12 μm, 13 μm, 14 μm, 15 μm, 16 μm, 17 μm, 18 μm, 19 μm, 20 μm, 21 μm, 22 μm, 23 μm, 24 μm, 25 μm, 26 μm, 27 μm, 28 μm, 29 μm or 30 μm; the injection angle is preferably 30 to 120 °, specifically 60 °, 65 °, 70 °, 75 °, 80 °, 85 °, 90 °, 95 °, 100 °, 105 °, 110 °, 115 °, or 120 °.
In the step a), during the dynamic mixing, the maximum movement speed of the aluminum nitride powder is 10-60 m/s, and specifically may be 10m/s, 12m/s, 15m/s, 17m/s, 20m/s, 23m/s, 25m/s, 27m/s, 30m/s, 32m/s, 35m/s, 37m/s, 40m/s, 42m/s, 45m/s, 47m/s, 50m/s, 52m/s, 55m/s, 57m/s, or 60m/s.
In step a), the dynamic mixing means includes, but is not limited to, mechanical paddle mixing, vessel motion mixing, fluidized bed mixing, or pneumatic mixing.
In step a), the temperature of the dynamic mixing is preferably 50-150 ℃, specifically 50 ℃, 55 ℃, 60 ℃, 65 ℃, 70 ℃, 75 ℃, 80 ℃, 85 ℃, 90 ℃, 95 ℃, 100 ℃, 105 ℃, 110 ℃, 115 ℃, 120 ℃, 125 ℃, 130 ℃, 135 ℃, 140 ℃, 145 ℃ or 150 ℃; the dynamic mixing time is preferably 1 to 24 hours, and specifically may be 1 hour, 2 hours, 3 hours, 4 hours, 5 hours, 6 hours, 7 hours, 8 hours, 9 hours, 10 hours, 11 hours, 12 hours, 13 hours, 14 hours, 15 hours, 16 hours, 17 hours, 18 hours, 19 hours, 20 hours, 21 hours, 22 hours, 23 hours or 24 hours.
In step a), the drying manner includes, but is not limited to, spray drying, fluidized bed drying, flash drying, pneumatic drying, vacuum drying, microwave drying, freeze drying or vacuum jet drying.
In step a), the drying temperature is preferably 80-200 ℃, and specifically can be 80 ℃, 85 ℃, 90 ℃, 95 ℃, 100 ℃, 105 ℃, 110 ℃, 115 ℃, 120 ℃, 125 ℃, 130 ℃, 135 ℃, 140 ℃, 145 ℃, 150 ℃, 155 ℃, 160 ℃, 165 ℃, 170 ℃, 175 ℃, 180 ℃, 185 ℃, 190 ℃, 195 ℃ or 200 ℃; the drying time is preferably 0.5 to 8 hours, and specifically may be 0.5 hour, 0.7 hour, 1 hour, 1.2 hours, 1.5 hours, 1.7 hours, 2 hours, 2.3 hours, 2.5 hours, 2.7 hours, 3 hours, 3.2 hours, 3.5 hours, 3.7 hours, 4 hours, 4.2 hours, 4.5 hours, 4.7 hours, 5 hours, 5.2 hours, 5.5 hours, 5.7 hours, 6 hours, 6.2 hours, 6.5 hours, 6.7 hours, 7 hours, 7.2 hours, 7.5 hours, 7.8 hours or 8 hours.
In the step a), the surface energy of the coated and modified aluminum nitride powder A obtained by coating and modification is preferably 20-30 mJ/m 2 Specifically, it may be 20mJ/m 2 、21mJ/m 2 、22mJ/m 2 、23mJ/m 2 、24mJ/m 2 、 25mJ/m 2 、26mJ/m 2 、27mJ/m 2 、28mJ/m 2 、29mJ/m 2 Or 30mJ/m 2 (ii) a The effective grafting rate of the coating agent is preferably 0.3-5%, and specifically may be 0.3%, 0.5%, 0.7%, 1%, 1.2%, 1.5%, 1.7%, 2%, 2.3%, 2.5%, 2.7%, 3%, 3.2%, 3.5%, 3.7%, 4%, 4.2%, 4.5%, 4.7%, or 5%, where the effective grafting rate refers to the percentage of the weight of the coated powder layer in the total weight of the powder; before and after coating D 50 The change rate of the particle diameter is preferably not more than 150%, and specifically may be 5%, 10%, 15%, 20%, 25%, 30%, 35%, 40%, 45%, 50%, 52%, 53%, 55%, 60%, 65%, 70%, 75%, 80%, 85%, 90%, 95%, 100%,105%, 110%, 115%, 120%, 125%, 130%, 135%, 140%, 145% or 150%; the residual ratio of the unreacted coating agent is preferably 2000ppm or less, and specifically may be 50ppm, 100ppm, 150ppm, 200ppm, 300ppm, 400ppm, 500ppm, 600ppm, 700ppm, 800ppm, 900ppm, 1000ppm, 1100ppm, 1200ppm, 1300ppm, 1400ppm, 1500ppm, 1600ppm, 1700ppm, 1800ppm, 1900ppm or 2000ppm.
b) For D 50 The aluminum nitride powder with the grain diameter of 2-10 mu m is coated and modified according to the following method:
and dynamically mixing the aluminum nitride powder and the coating agent diluent in a powder mixer, and then reacting and drying to obtain the coated modified aluminum nitride powder B.
In step b), the particle size of the aluminum nitride powder can be specifically 2 μm, 2.5 μm, 3 μm, 3.5 μm, 4 μm, 4.5 μm, 5 μm, 5.5 μm, 6 μm, 6.5 μm, 7 μm, 7.5 μm, 8 μm, 8.5 μm, 9 μm, 9.5 μm or 10 μm.
In the step b), the sphericity of the aluminum nitride powder is preferably not less than 85%, and specifically may be 85%, 86%, 87%, 88%, 89%, 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98% or 99%.
In step b), the oxygen content of the aluminum nitride powder is preferably 0.1 to 0.9wt%, and specifically may be 0.1wt%, 0.15wt%, 0.2wt%, 0.25wt%, 0.3wt%, 0.35wt%, 0.4wt%, 0.45wt%, 0.5wt%, 0.55wt%, 0.6wt%, 0.65wt%, 0.7wt%, 0.75wt%, 0.78wt%, 0.8wt%, 0.858wt%, or 0.98wt%; the carbon content of the aluminum nitride powder is preferably 0.01 to 0.4wt%, and specifically may be 0.01wt%, 0.03wt%, 0.05wt%, 0.07wt%, 0.1wt%, 0.12wt%, 0.15wt%, 0.17wt%, 0.2wt%, 0.23wt%, 0.25wt%, 0.27wt%, 0.3wt%, 0.32wt%, 0.35wt%, 0.37wt%, or 0.4wt%.
In the step b), the specific surface area of the aluminum nitride powder is preferably 0.2-1.5 m 2 A specific value of 0.2 m/g 2 /g、0.3m 2 /g、0.4m 2 /g、0.5m 2 /g、0.6m 2 /g、0.7m 2 /g、0.8m 2 /g、0.9m 2 /g、 1m 2 /g、1.1m 2 /g、1.2m 2 /g、1.3m 2 /g、1.4m 2 G or 1.5m 2 /g。
In the step b), the true density of the aluminum nitride powder is preferably 3.2-3.3 g/cm 3 Specifically, it may be 3.2g/cm 3 、3.21g/cm 3 、3.22g/cm 3 、3.23g/cm 3 、3.24g/cm 3 、3.25g/cm 3 、3.26g/cm 3 、 3.27g/cm 3 、3.28g/cm 3 、3.29g/cm 3 Or 3.3g/cm 3 。
In step b), the water content of the aluminum nitride powder before mixing is 0.1 to 3%, specifically 0.1%, 0.2%, 0.3%, 0.4%, 0.5%, 0.6%, 0.7%, 0.8%, 0.9%, 1%, 1.1%, 1.2%, 1.3%, 1.4%, 1.5%, 1.6%, 1.7%, 1.8%, 1.9%, 2%, 2.1%, 2.2%, 2.3%, 2.4%, 2.5%, 2.6%, 2.7%, 2.8%, 2.9%, or 3%. In the invention, the aluminum nitride powder can be placed in the dryer for a certain time, so that the water content of the aluminum nitride powder can be regulated and controlled to meet the requirement.
In the step b), the filling factor of the aluminum nitride powder in the powder mixer is 30 to 70%, specifically 30%, 31%, 32%, 33%, 34%, 35%, 36%, 37%, 38%, 39%, 40%, 41%, 42%, 43%, 44%, 45%, 46%, 47%, 48%, 49%, 50%, 51%, 52%, 53%, 54%, 55%, 56%, 57%, 58%, 59%, 60%, 61%, 62%, 63%, 64%, 65%, 66%, 67%, 68%, 69% or 70%.
In the step b), the components of the coating agent diluent comprise a coating agent and a solvent; the coating agent is preferably a silane oligomer and/or an organosilicon compound containing alkoxy groups; the number average molecular weight of the silane oligomer is preferably 300 to 600, and specifically may be 300, 350, 400, 450, 500, 550 or 600; the organosilicon compound containing alkoxy is preferably long-chain alkyl triethoxysilane, more preferably C 10 Alkyltriethoxysilanes; the reaction degree of the coating agent is preferably less than or equal to 10%, and specifically can be 1%, 2%, 3%, 4%, 5%, 6%, 7%, 8%, 9% or10 percent, wherein the reaction degree refers to the percentage of the mass of the coating agent materials participating in the reaction to the total amount of the coating agent.
In the step b), the solvent of the coating agent diluent is preferably one or more of water, alcohol and petroleum hydrocarbon, more preferably a mixture of water and ethanol, and the mass ratio of the water to the ethanol is preferably (0.01-0.1): 1.5, specifically can be 0.01.
In the step b), in the coating agent diluent, the mass ratio of the coating agent to the solvent is 1: (0.5 to 5), specifically 1.
In the step b), the amount of the coating agent is 0.5 to 4% of the aluminum nitride powder, specifically, 0.5%, 0.6%, 0.7%, 0.8%, 0.9%, 1%, 1.1%, 1.2%, 1.3%, 1.4%, 1.5%, 1.6%, 1.7%, 1.8%, 1.9%, 2%, 2.1%, 2.2%, 2.3%, 2.4%, 2.5%, 2.6%, 2.7%, 2.8%, 2.9%, 3%, 3.1%, 3.2%, 3.3%, 3.4%, 3.5%, 3.6%, 3.7%, 3.8%, 3.9%, or 4%.
In the step b), the diluent of the coating agent is sprayed into a powder mixer in a spraying mode to participate in dynamic mixing; in the spraying process, the distance from the nozzle to the material is preferably 10-50 cm, more preferably 10-30 cm, and specifically 10cm, 11cm, 12cm, 13cm, 14cm, 15cm, 16cm, 17cm, 18cm, 19cm, 20cm, 21cm, 22cm, 23cm, 24cm, 25cm, 26cm, 27cm, 28cm, 29cm or 30cm; the diameter of the atomized droplets is preferably 1 to 30 μm, and may be, in particular, 1 μm, 2 μm, 3 μm, 4 μm, 5 μm, 6 μm, 7 μm, 8 μm, 9 μm, 10 μm, 11 μm, 12 μm, 13 μm, 14 μm, 15 μm, 16 μm, 17 μm, 18 μm, 19 μm, 20 μm, 21 μm, 22 μm, 23 μm, 24 μm, 25 μm, 26 μm, 27 μm, 28 μm, 29 μm or 30 μm; the injection angle is preferably 30 to 120 °, specifically 60 °, 65 °, 70 °, 75 °, 80 °, 85 °, 90 °, 95 °, 100 °, 105 °, 110 °, 115 °, or 120 °.
In the step b), the maximum movement speed of the aluminum nitride powder in the dynamic mixing process is 5-30 m/s, and specifically may be 5m/s, 6m/s, 7m/s, 8m/s, 9m/s, 10m/s, 11m/s, 12m/s, 13m/s, 14m/s, 15m/s, 16m/s, 17m/s, 18m/s, 19m/s, 20m/s, 21m/s, 22m/s, 23m/s, 24m/s, 25m/s, 26m/s, 27m/s, 28m/s, 29m/s or 30m/s.
In step b), the dynamic mixing mode includes but is not limited to mechanical paddle mixing, vessel motion mixing, fluidized bed mixing or pneumatic mixing.
In step b), the temperature of the dynamic mixing is preferably 50-150 ℃, and specifically can be 50 ℃, 55 ℃, 60 ℃, 65 ℃, 70 ℃, 75 ℃, 80 ℃, 85 ℃, 90 ℃, 95 ℃, 100 ℃, 105 ℃, 110 ℃, 115 ℃, 120 ℃, 125 ℃, 130 ℃, 135 ℃, 140 ℃, 145 ℃ or 150 ℃; the dynamic mixing time is preferably 1 to 24 hours, and specifically may be 1 hour, 2 hours, 3 hours, 4 hours, 5 hours, 6 hours, 7 hours, 8 hours, 9 hours, 10 hours, 11 hours, 12 hours, 13 hours, 14 hours, 15 hours, 16 hours, 17 hours, 18 hours, 19 hours, 20 hours, 21 hours, 22 hours, 23 hours or 24 hours.
In step b), the drying means includes, but is not limited to, spray drying, fluidized bed drying, flash drying, pneumatic drying, vacuum drying, microwave drying, freeze drying or vacuum jet drying.
In step b), the drying temperature is preferably 80-200 deg.C, specifically 80 deg.C, 85 deg.C, 90 deg.C, 95 deg.C, 100 deg.C, 105 deg.C, 110 deg.C, 115 deg.C, 120 deg.C, 125 deg.C, 130 deg.C, 135 deg.C, 140 deg.C, 145 deg.C, 155 deg.C, 160 deg.C, 165 deg.C, 170 deg.C, 175 deg.C, 180 deg.C, 185 deg.C, 190 deg.C, 195 deg.C or 200 deg.C; the drying time is preferably 0.5 to 8 hours, and specifically may be 0.5 hour, 0.7 hour, 1 hour, 1.2 hours, 1.5 hours, 1.7 hours, 2 hours, 2.3 hours, 2.5 hours, 2.7 hours, 3 hours, 3.2 hours, 3.5 hours, 3.7 hours, 4 hours, 4.2 hours, 4.5 hours, 4.7 hours, 5 hours, 5.2 hours, 5.5 hours, 5.7 hours, 6 hours, 6.2 hours, 6.5 hours, 6.7 hours, 7 hours, 7.2 hours, 7.5 hours, 7.8 hours or 8 hours.
In the step B), the surface energy of the coated and modified aluminum nitride powder B obtained by coating and modification is preferably 18-26 mJ/m 2 Specifically, it may be 18mJ/m 2 、19mJ/m 2 、20mJ/m 2 、21mJ/m 2 、22mJ/m 2 、23mJ/m 2 、24mJ/m 2 、25mJ/m 2 Or 26mJ/m 2 (ii) a The effective grafting percentage of the coating agent is preferably 0.2 to 4%, and specifically may be 0.2%, 0.3%, 0.4%, 0.5%, 0.6%, 0.7%, 0.8%, 0.9%, 1%, 1.1%, 1.2%, 1.3%, 1.4%, 1.5%, 1.7%, 2%, 2.3%, 2.5%, 2.7%, 3%, 3.2%, 3.5%, 3.7%, or 4%; before and after coating D 50 The change rate of the particle diameter is preferably less than or equal to 100%, and specifically can be 1%, 2%, 3%, 4%, 5%, 6.25%, 7%, 10%, 15%, 20%, 25%, 30%, 35%, 40%, 45%, 50%, 55%, 60%, 65%, 70%, 75%, 80%, 85%, 90%, 95%, 100%; the residual ratio of the unreacted coating agent is preferably 2000ppm or less, and specifically may be 50ppm, 100ppm, 150ppm, 200ppm, 300ppm, 400ppm, 500ppm, 600ppm, 700ppm, 800ppm, 900ppm, 1000ppm, 1100ppm, 1200ppm, 1300ppm, 1400ppm, 1500ppm, 1600ppm, 1700ppm, 1800ppm, 1900ppm or 2000ppm.
c) For D 50 The aluminum nitride powder with the grain diameter of more than 10 mu m is coated and modified according to the following method:
and dynamically mixing the aluminum nitride powder and the coating agent diluent in a powder mixer, and then reacting and drying to obtain the coated modified aluminum nitride powder C.
In step c), the particle size of the aluminum nitride powder is preferably 10 to 100 μm (excluding the left end value of 10 μm), and specifically may be 15 μm, 20 μm, 25 μm, 30 μm, 35 μm, 40 μm, 45 μm, 50 μm, 55 μm, 60 μm, 65 μm, 70 μm, 75 μm, 80 μm, 85 μm, 90 μm, 95 μm, or 100 μm.
In the step c), the sphericity of the aluminum nitride powder is preferably not less than 90%, and specifically may be 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98% or 99%.
In step c), the aluminum nitride powder preferably has an oxygen content of 0.1 to 1wt%, and specifically may be 0.1wt%, 0.15wt%, 0.2wt%, 0.25wt%, 0.3wt%, 0.35wt%, 0.4wt%, 0.45wt%, 0.5wt%, 0.55wt%, 0.6wt%, 0.65wt%, 0.7wt%, 0.75wt%, 0.78wt%, 0.8wt%, 0.82wt%, 0.85wt%, 0.87wt%, 0.9wt%, 0.92wt%, 0.95wt%, 0.97wt%, or 1wt%; the carbon content of the aluminum nitride powder is preferably 0.01 to 0.2wt%, and specifically may be 0.01wt%, 0.02wt%, 0.03wt%, 0.04wt%, 0.05wt%, 0.06wt%, 0.07wt%, 0.08wt%, 0.09wt%, 0.1wt%, 0.11wt%, 0.12wt%, 0.13wt%, 0.14wt%, 0.15wt%, 0.16wt%, 0.17wt%, 0.18wt%, 0.19wt%, or 0.2wt%.
In step c), the specific surface area of the aluminum nitride powder is preferably 0.01 to 0.5m 2 A specific value of 0.01 m/g 2 /g、0.02m 2 /g、0.03m 2 /g、0.04m 2 /g、0.05m 2 /g、0.07m 2 /g、0.1m 2 /g、0.15m 2 /g、 0.2m 2 /g、0.25m 2 /g、0.3m 2 /g、0.35m 2 /g、0.4m 2 /g、0.45m 2 In g or 0.5m 2 /g。
In the step c), the true density of the aluminum nitride powder is preferably 3.2-3.3 g/cm 3 Specifically, it may be 3.2g/cm 3 、3.21g/cm 3 、3.22g/cm 3 、3.23g/cm 3 、3.24g/cm 3 、3.25g/cm 3 、3.26g/cm 3 、 3.27g/cm 3 、3.28g/cm 3 、3.29g/cm 3 Or 3.3g/cm 3 。
In step c), the aluminum nitride powder may have a water content of 0.05 to 3% before mixing, specifically 0.05%, 0.1%, 0.15%, 0.2%, 0.3%, 0.4%, 0.5%, 0.6%, 0.7%, 0.8%, 0.9%, 1%, 1.1%, 1.2%, 1.3%, 1.4%, 1.5%, 1.6%, 1.7%, 1.8%, 1.9%, 2%, 2.3%, 2.5%, 2.7%, or 3%. In the invention, the aluminum nitride powder can be placed in the dryer for a certain time, so that the water content of the aluminum nitride powder can be regulated and controlled to meet the requirement.
In step c), the filling factor of the aluminum nitride powder in the powder mixer is 20 to 60%, specifically 20%, 21%, 22%, 23%, 24%, 25%, 26%, 27%, 28%, 29%, 30%, 31%, 32%, 33%, 34%, 35%, 36%, 37%, 38%, 39%, 40%, 41%, 42%, 44%, 45%, 46%, 47%, 48%, 49%, 50%, 51%, 52%, 53%, 54%, 55%, 56%, 57%, 58%, 59%, or 60%.
In step c), the components of the coating agent diluent comprise a coating agent and a solvent; the coating agent is preferably a silane oligomer and/or an organosilicon compound containing alkoxy; the number average molecular weight of the silane oligomer is preferably 300 to 600, and specifically may be 300, 350, 400, 450, 500, 550 or 600; the organosilicon compound containing alkoxy is preferably long-chain alkyl triethoxysilane, more preferably C 10 Alkyltriethoxysilanes; the reaction degree of the coating agent is preferably less than or equal to 10%, and specifically can be 1%, 2%, 3%, 4%, 5%, 6%, 7%, 8%, 9% or 10%, and the reaction degree refers to the percentage of the mass of the coating agent material participating in the reaction to the total amount of the coating agent.
In step c), the solvent of the diluent of the coating agent is preferably one or more of water, alcohol and petroleum hydrocarbon, more preferably a mixture of water and petroleum hydrocarbon, and the mass ratio of the water to the petroleum hydrocarbon is preferably (0.01-0.1): 1.5, specifically can be 0.01.
In the step c), in the coating agent diluent, the mass ratio of the coating agent to the solvent is 1: (0.5 to 5), specifically 1.
In step c), the amount of the coating agent is 0.5 to 3% by mass of the aluminum nitride powder, and specifically may be 0.5%, 0.6%, 0.7%, 0.8%, 0.9%, 1%, 1.1%, 1.2%, 1.3%, 1.4%, 1.5%, 1.6%, 1.7%, 1.8%, 1.9%, 2%, 2.1%, 2.2%, 2.3%, 2.4%, 2.5%, 2.6%, 2.7%, 2.8%, 2.9% or 3%.
In the step c), the coating agent diluent is sprayed into a powder mixer in a spraying mode to participate in dynamic mixing; in the spraying process, the distance from the nozzle to the material is preferably 10-50 cm, and specifically can be 10cm, 12cm, 15cm, 17cm, 20cm, 23cm, 25cm, 27cm, 30cm, 32cm, 35cm, 37cm, 40cm, 42cm, 45cm, 47cm or 50cm; the diameter of the atomized droplets is preferably 1 to 30 μm, and specifically may be 1 μm, 2 μm, 3 μm, 4 μm, 5 μm, 6 μm, 7 μm, 8 μm, 9 μm, 10 μm, 11 μm, 12 μm, 13 μm, 14 μm, 15 μm, 16 μm, 17 μm, 18 μm, 19 μm, 20 μm, 21 μm, 22 μm, 23 μm, 24 μm, 25 μm, 26 μm, 27 μm, 28 μm, 29 μm or 30 μm; the injection angle is preferably 30 to 120 °, specifically 60 °, 65 °, 70 °, 75 °, 80 °, 85 °, 90 °, 95 °, 100 °, 105 °, 110 °, 115 °, or 120 °.
In the step c), in the dynamic mixing process, the maximum movement speed of the aluminum nitride powder is 2-15 m/s, and specifically may be 2m/s, 3m/s, 4m/s, 5m/s, 6m/s, 7m/s, 8m/s, 9m/s, 10m/s, 11m/s, 12m/s, 13m/s, 14m/s or 15m/s.
In step c), the dynamic mixing means includes, but is not limited to, mechanical paddle mixing, vessel motion mixing, fluidized bed mixing, or pneumatic mixing.
In step c), the temperature of the dynamic mixing is preferably 50-150 ℃, specifically 50 ℃, 55 ℃, 60 ℃, 65 ℃, 70 ℃, 75 ℃, 80 ℃, 85 ℃, 90 ℃, 95 ℃, 100 ℃, 105 ℃, 110 ℃, 115 ℃, 120 ℃, 125 ℃, 130 ℃, 135 ℃, 140 ℃, 145 ℃ or 150 ℃; the dynamic mixing time is preferably 1 to 24 hours, and specifically may be 1 hour, 2 hours, 3 hours, 4 hours, 5 hours, 6 hours, 7 hours, 8 hours, 9 hours, 10 hours, 11 hours, 12 hours, 13 hours, 14 hours, 15 hours, 16 hours, 17 hours, 18 hours, 19 hours, 20 hours, 21 hours, 22 hours, 23 hours or 24 hours.
In step c), the drying means includes, but is not limited to, spray drying, fluidized bed drying, flash drying, pneumatic drying, vacuum drying, microwave drying, freeze drying or vacuum jet drying.
In step c), the drying temperature is preferably 80-200 deg.C, specifically 80 deg.C, 85 deg.C, 90 deg.C, 95 deg.C, 100 deg.C, 105 deg.C, 110 deg.C, 115 deg.C, 120 deg.C, 125 deg.C, 130 deg.C, 135 deg.C, 140 deg.C, 145 deg.C, 150 deg.C, 155 deg.C, 160 deg.C, 165 deg.C, 170 deg.C, 175 deg.C, 180 deg.C, 185 deg.C, 190 deg.C, 195 deg.C or 200 deg.C; the drying time is preferably 0.5-8 h, and specifically may be 0.5h, 0.7h, 1h, 1.2h, 1.5h, 1.7h, 2h, 2.3h, 2.5h, 2.7h, 3h, 3.2h, 3.5h, 3.7h, 4h, 4.2h, 4.5h, 4.7h, 5h, 5.2h, 5.5h, 5.7h, 6h, 6.2h, 6.5h, 6.7h, 7h, 7.2h, 7.5h, 7.8h or 8h.
In the step C), the surface energy of the coated and modified aluminum nitride powder C obtained by coating and modifying is preferably 18-24 mJ/m 2 Specifically, it may be 18mJ/m 2 、18.5mJ/m 2 、19mJ/m 2 、19.5mJ/m 2 、20mJ/m 2 、 20.5mJ/m 2 、21mJ/m 2 、21.5mJ/m 2 、22mJ/m 2 、22.5mJ/m 2 、23mJ/m 2 、23.5mJ/m 2 Or 24mJ/m 2 (ii) a The effective grafting ratio of the coating agent is preferably 0.11 to 3%, and specifically may be 0.11%, 0.15%, 0.17%, 0.2%, 0.3%, 0.4%, 0.5%, 0.6%, 0.7%, 0.8%, 0.9%, 1%, 1.2%, 1.5%, 1.7%, 2%, 2.3%, 2.5%, 2.7%, or 3%; before and after coating D 50 The rate of change in particle size is preferably not more than 30%, and specifically may be 0.05%, 0.1%, 0.15%, 0.2%, 0.25%, 0.3%, 0.5%, 0.7%, 1%, 1.5%, 2%, 2.5%, 3%, 3.5%, 4%, 4.5%, 5%, 5.2%, 5.3%, 6%, 7%, 8%, 9%, 10%, 12%, 15%, 17%, 20%, 23%, 25%, 27%, or 30%; the residual ratio of the unreacted coating agent is preferably 2000ppm or less, and specifically may be 50ppm, 100ppm, 150ppm, 200ppm, 300ppm, 400ppm, 500ppm, 600ppm, 700ppm, 800ppm, 900ppm, 1000ppm, 1100ppm, 1200ppm, 1300ppm, 1400ppm, 1500ppm, 1600ppm, 1700ppm, 1800ppm, 1900ppm or 2000ppm.
The invention also provides a modified aluminum nitride powder, and the components of the modified aluminum nitride powder comprise one or more of the coated modified aluminum nitride powders prepared in the steps a) -c) of the coating modification method in the technical scheme; i.e. including by D 50 Coated modified aluminum nitride powder (coated modified aluminum nitride powder A) prepared by using aluminum nitride powder with particle size less than 2 mu m as raw material and D 50 Coating modified nitriding prepared by taking aluminum nitride powder with particle size of 2-10 mu m as raw materialAluminum powder (coating modified aluminum nitride powder B) and aluminum powder D 50 One, two or three of the coated modified aluminum nitride powder (coated modified aluminum nitride powder C) prepared by using the aluminum nitride powder with the particle size of more than 10 mu m as a raw material.
The invention also provides an application of the modified aluminum nitride powder in the technical scheme, and the modified aluminum nitride powder is used as a heat-conducting filler for preparing a thermal interface material.
In the application provided by the invention, only the modified aluminum nitride powder can be adopted as the heat-conducting filler for preparing the thermal interface material; the volume ratio of the coated modified aluminum nitride powder A to the coated modified aluminum nitride powder B to the coated modified aluminum nitride powder C is preferably 1: (1-4): (2 to 6), specifically, 1.
In the application provided by the invention, the modified aluminum nitride powder can be compounded with other heat-conducting fillers to be used as the heat-conducting filler for preparing the thermal interface material; wherein the other thermally conductive fillers include, but are not limited to, alumina powder. In one embodiment provided herein, the thermally conductive filler used to prepare the thermal interface material comprises a primary filler, a secondary filler, and a tertiary filler; wherein the first-stage filler comprises the modified aluminum nitride powder A, alumina powder and D of the alumina powder 50 The particle size is preferably 0.1-1 μm, specifically 0.5 μm, and the volume ratio of the modified aluminum nitride powder A to the alumina powder is preferably 1: (2-6), specifically 1; the second-stage filler comprises the modified aluminum nitride powder B, alumina powder and D of the alumina powder 50 The particle size is preferably 2-5 μm, specifically 3 μm, and the volume ratio of the modified aluminum nitride powder B to the alumina powder is preferably 3: (0.5 to 2), and specifically may be 3; the third-level filler is the coated modified aluminum nitride powder C; the volume ratio of the first-stage filler to the second-stage filler to the third-stage filler is preferably 1: (1-4): (2 to 6), specifically, 1.
In the application provided by the invention, the thermal interface material can be a single-component thermal interface material or a two-component thermal interface material.
In the applications provided by the present invention, the substrate in the thermal interface material is preferably organic for a one-component thermal interface materialA silicon polymer; the components of the organic silicon polymer include but are not limited to one or more of dimethyl silicone oil, phenyl silicone oil, vinyl silicone oil and hydrogen-containing silicone oil, and are preferably a mixture of vinyl silicone oil and hydrogen-containing silicone oil; the molar ratio of the vinyl silicone oil in terms of vinyl groups to the hydrogen-containing silicone oil in terms of hydrosilyl groups is preferably (0.5 to 2): 1, specifically 1.1; the surface energy of the organosilicon polymer is preferably 18-30 mJ/m 2 Specifically, it may be 18mJ/m 2 、19mJ/m 2 、20mJ/m 2 、 21mJ/m 2 、22mJ/m 2 、23mJ/m 2 、24mJ/m 2 、25mJ/m 2 、26mJ/m 2 、27mJ/m 2 、28mJ/m 2 、 29mJ/m 2 Or 30mJ/m 2 (ii) a The thermal interface material also contains a certain amount of catalyst, and the catalyst is Karstedt catalyst preferably; the content of the catalyst is preferably 0.2 to 1wt%, specifically 0.2wt%, 0.3wt%, 0.4wt%, 0.5wt%, 0.6wt%, 0.7wt%, 0.8wt%, 0.9wt%, or 1wt%, based on the mass of the thermal interface material substrate (silicone polymer); the volume filling rate of the heat conductive filler in the thermal interface material is preferably 70% or more, more preferably 70 to 90%, and specifically may be 70%, 71%, 72%, 73%, 74%, 75%, 76%, 77%, 78%, 79%, 80%, 81%, 82%, 83%, 84%, 85%, 86%, 87%, 88%, 89%, or 90%.
In the application provided by the invention, for the two-component thermal interface material, the base material in the component A is preferably vinyl silicone oil; the surface energy of the A component substrate is preferably 18 to 30mJ/m 2 Specifically, it may be 18mJ/m 2 、19mJ/m 2 、20mJ/m 2 、21mJ/m 2 、22mJ/m 2 、23mJ/m 2 、24mJ/m 2 、25mJ/m 2 、 26mJ/m 2 、27mJ/m 2 、28mJ/m 2 、29mJ/m 2 Or 30mJ/m 2 (ii) a The component A also contains a certain amount of catalyst, and the catalyst is preferably Karstedt catalyst; the content of the catalyst is preferably 0.5 to 2wt%, specifically 0.5wt%, 0.6wt%, 0.7wt%, 0.8wt%, 0.9wt%, based on the mass of the A-component base material (e.g., vinyl silicone oil)1, 1.1, 1.2, 1.3, 1.4, 1.5, 1.6, 1.7, 1.8, 1.9, or 2wt%; the volume filling rate of the heat-conducting filler in the component A is preferably equal to or more than 70%, more preferably 70-90%, and specifically 70%, 71%, 72%, 73%, 74%, 75%, 76%, 77%, 78%, 79%, 80%, 81%, 82%, 83%, 84%, 85%, 86%, 87%, 88%, 89% or 90%; the base material in the component B is preferably vinyl silicone oil and hydrogen-containing silicone oil, and the molar ratio of the vinyl silicone oil in terms of vinyl groups to the hydrogen-containing silicone oil in terms of hydrosilyl groups is preferably (0.5-2): 1, specifically 1.1; the surface energy of the B component substrate is preferably 18 to 30mJ/m 2 Specifically, it may be 18mJ/m 2 、19mJ/m 2 、20mJ/m 2 、21mJ/m 2 、22mJ/m 2 、23mJ/m 2 、24mJ/m 2 、 25mJ/m 2 、26mJ/m 2 、27mJ/m 2 、28mJ/m 2 、29mJ/m 2 Or 30mJ/m 2 (ii) a The volume filling rate of the heat-conducting filler in the component B is preferably equal to or more than 70%, more preferably 70-90%, and specifically 70%, 71%, 72%, 73%, 74%, 75%, 76%, 77%, 78%, 79%, 80%, 81%, 82%, 83%, 84%, 85%, 86%, 87%, 88%, 89% or 90%; the volume ratio of the a component to the B component is preferably 1.
According to the technical scheme provided by the invention, the aluminum nitride powder is subjected to graded and differentiated fine coating modification treatment, and the coating layer of the aluminum nitride powder can be accurately regulated and controlled, so that the finally obtained modified aluminum nitride can have effective coating grafting rate, coating layer thickness and D meeting expected requirements 50 Particle size and surface energy. The experimental result shows that the modified aluminum nitride prepared by the coating modification method has excellent performances and can be used as a filler for preparing high-thermal-conductivity, high-stability and low-viscosity thermal interface materials (thermal-conductivity gel, thermal-conductivity silicone grease and the like).
For the sake of clarity, the following examples are given in detail.
Example 1
(1) According to D 50 Difference in particle sizeThe aluminum nitride powder is divided into three levels, and differential coating modification is carried out, and the method specifically comprises the following steps:
(1.1) coating modification of the primary aluminum nitride powder, which comprises the following specific processes:
d of first-order aluminum nitride powder 50 The particle diameter was 0.8 μm, the oxygen content was 0.78wt%, the carbon content was 0.3wt%, the sphericity was 90%, and the true density was 3.28g/cm 3 Specific surface area of 2.5m 2 (ii)/g; placing the first-stage aluminum nitride powder body in a dryer>After 24 hours, the water content of the powder is 0.1%;
coating agent selection C 10 Alkyl triethoxy silane, the reaction degree is 2%; mixing the coating agent, water and absolute ethyl alcohol according to a mass ratio of 1;
filling the primary aluminum nitride powder taken out of the dryer into a fluidized bed powder mixer, and controlling the filling coefficient of the powder to be 60%; introducing the diluent of the coating agent into a sprayer, starting a fluidized bed powder mixer, spraying, setting the spraying air pressure to control the size of atomized liquid drops to be 5 micrometers, setting the distance from a nozzle to a material to be 20cm, and setting the spraying angle to be 60 degrees; in the spraying process, the amount of the coating agent is 3wt% of the mass of the first-level aluminum nitride powder;
in the operation process of the fluidized bed powder mixer, adjusting the air flow speed of the powder mixer to control the maximum movement speed of the powder to be 30m/s when the coating agent is mixed with the powder; the temperature during mixing is controlled to be 50 ℃, and the mixing time is 3h;
after mixing, conveying the mixture to a fluidized bed dryer for drying at the temperature of 130 ℃ for 4 hours to obtain first-level coated modified aluminum nitride powder;
the first-level coating modified powder is characterized in that: d 50 The grain diameter is 1.0 mu m, the effective grafting rate of the coating agent of the coating layer is 2 percent, and the surface energy is 26mJ/m 2 The residual ratio of the unreacted coating agent was 100ppm.
(1.2) coating modification of the secondary aluminum nitride powder, which comprises the following specific steps:
d of second-stage aluminum nitride powder 50 Particle size of 5.0 μm, oxygen content of 0.8wt%, and carbonThe element content is 0.2%, the sphericity is 95%, and the true density is 3.27g/cm 3 Specific surface area of 0.5m 2 (iv) g; placing the second-stage aluminum nitride powder body in a dryer>After 24 hours, the water content of the powder is 0.3%;
the coating agent is selected from silane oligomer, the number average molecular weight is 400, and the reaction degree is 5%; mixing the coating agent, water and absolute ethyl alcohol according to a mass ratio of 1.05;
filling the second-stage aluminum nitride powder taken out of the dryer into a container moving type powder mixer, and controlling the filling coefficient of the powder to be 40%; introducing the diluent of the coating agent into a sprayer, starting a container motion type powder mixer, spraying, setting the spraying air pressure to control the size of atomized liquid drops to be 10 micrometers, setting the distance between a nozzle and the material to be 20cm, and setting the spraying angle to be 60 degrees; in the spraying process, the amount of the coating agent is 1.5wt% of the mass of the secondary aluminum nitride powder;
in the operation process of the container motion type high-speed powder mixer, the container rotating speed of the powder mixer is adjusted to control the maximum motion speed of the powder to be 20m/s when the coating agent is mixed with the powder; the temperature during mixing is controlled to be 80 ℃, and the mixing time is 2h;
after mixing, conveying the mixture to an airflow dryer for drying at the drying temperature of 80 ℃ for 2 hours to obtain secondary coated modified aluminum nitride powder;
the secondary coating modified aluminum nitride powder is characterized in that: d 50 The grain diameter is 5.2 mu m, the effective grafting ratio of the coating agent of the coating layer is 1 percent, and the surface energy is 24mJ/m 2 The comparative D50 particle size change rate before and after coating was 4%, and the unreacted coating agent residue rate was 500ppm.
(1.3) coating modification of the three-level aluminum nitride powder, which comprises the following specific steps:
d of three-stage aluminum nitride powder 50 The grain diameter is 80 μm, the oxygen content is 0.7wt%, the carbon content is 0.1wt%, the sphericity is 96%, and the true density is 3.28g/cm 3 Specific surface area 0.02m 2 (ii)/g; putting the three-stage aluminum nitride powder in a dryer for placing>After 24 hours, the water content of the powder is 0.05%;
the coating agent is selected from silane oligomer with the number average molecular weight of 600 and the reaction degree of 1%; mixing the coating agent, water and petroleum hydrocarbon according to a mass ratio of 1;
filling the three-stage aluminum nitride powder taken out of the dryer into a mechanical paddle powder mixer, and controlling the filling coefficient of the powder to be 40%; introducing the diluent of the coating agent into a sprayer, starting a mechanical paddle powder mixer, spraying, setting the spraying air pressure to control the size of atomized liquid drops to be 20 micrometers, setting the distance between a nozzle and the material to be 30cm, and setting the spraying angle to be 60 degrees; in the spraying process, the using amount of the coating agent is 0.9 percent of the mass of the three-level aluminum nitride powder;
in the operation process of the mechanical paddle powder mixer, the rotating speed of the paddle of the powder mixer is adjusted to control the maximum moving speed of the powder to be 10m/s when the coating agent is mixed with the powder; the temperature during mixing is controlled to be 100 ℃, and the mixing time is 1h;
after mixing, conveying the mixture to a microwave vacuum dryer for drying at the drying temperature of 100 ℃ for 5 hours to obtain three-level coated modified aluminum nitride powder;
the three-level coated modified aluminum nitride powder is characterized in that: d 50 The grain diameter is 82 mu m, the effective grafting rate of the coating agent of the coating layer is 0.5 percent, and the surface energy is 22mJ/m 2 The residual rate of the unreacted coating agent was 2000ppm.
(2) Applying the modified aluminum nitride prepared in the step (1) to the preparation of the heat-conducting gel, and specifically comprises the following steps:
the primary coating modified aluminum nitride powder, the secondary coating modified aluminum nitride powder and the tertiary coating modified aluminum nitride powder are mixed in batches according to the volume ratio of 1 2 The organosilicon polymer is a mixture of vinyl silicone oil and hydrogen-containing silicone oil, the molar ratio of vinyl of the vinyl silicone oil to hydrosil of the hydrogen-containing silicone oil is 1.1; the equipment used for mixing is dispersed in a 1L double-planetary mixer, the rotation speed of the blades is 100rpm, and the mixing time is 3h; mixingAfter the reaction is finished, vacuumizing to-98 kPa to obtain single-component heat-conducting gel;
the heat-conducting gel is characterized in that: the heat conductivity coefficient of the solidified gel is 10W/(m DEG C); the extrusion speed of a 30ccEDF dispensing hose phi 2.41mm needle head under 90psi is more than 40g/min, the flow rate attenuation is less than 5% after continuous dispensing for 24h, and the extrusion speed attenuation is less than 10% in 6 months of storage period.
Example 2
(1) According to D 50 The aluminum nitride powder is divided into three stages according to different particle sizes, and differential coating modification is carried out, and the method specifically comprises the following steps:
(1.1) coating modification of the primary aluminum nitride powder, which comprises the following specific steps:
d of first-order aluminum nitride powder 50 The particle diameter was 1.9 μm, the oxygen content was 0.78wt%, the carbon content was 0.3wt%, the sphericity was 90%, and the true density was 3.28g/cm 3 Specific surface area of 2.5m 2 (ii)/g; placing the first-stage aluminum nitride powder body in a dryer>After 24 hours, the water content of the powder is 0.1%;
coating agent selection C 10 Alkyl triethoxy silane, the reaction degree is 2%; mixing the coating agent, water and absolute ethyl alcohol according to a mass ratio of 1;
filling the primary aluminum nitride powder taken out of the dryer into a pneumatic mixer, and controlling the filling coefficient of the powder to be 50%; introducing the diluent of the coating agent into a sprayer, starting a fluidized bed powder mixer, spraying, setting the spraying air pressure to control the size of atomized liquid drops to be 5 micrometers, setting the distance from a nozzle to a material to be 20cm, and setting the spraying angle to be 60 degrees; in the spraying process, the amount of the coating agent is 3wt% of the mass of the first-grade aluminum nitride powder;
during the operation of the pneumatic mixer, the air consumption and the pressure of the powder mixer are adjusted to control the maximum movement speed of the powder to be 20m/s when the coating agent is mixed with the powder; the temperature during mixing is controlled to be 50 ℃, and the mixing time is 3h;
after mixing, conveying the mixture to an airflow dryer for drying at the temperature of 130 ℃ for 0.5h to obtain first-stage coated modified aluminum nitride powder;
the first-level coating modified powder is characterized in that: d 50 The grain diameter is 2 mu m, the effective grafting rate of the coating agent of the coating layer is 0.3 percent, and the surface energy is 30mJ/m 2 The residual ratio of the unreacted coating agent was 100ppm.
(1.2) coating modification of the secondary aluminum nitride powder, which comprises the following specific steps:
d of second-stage aluminum nitride powder 50 The grain diameter is 8 mu m, the oxygen element content is 0.7wt percent, the carbon element content is 0.2 percent, the sphericity is 85 percent, and the real density is 3.28g/cm 3 Specific surface area of 0.4m 2 (ii)/g; placing the secondary aluminum nitride powder in a dryer>After 24 hours, the water content of the powder is 0.3%;
the coating agent is selected from silane oligomer with the number average molecular weight of 300 and the reaction degree of 5%; mixing the coating agent, water and absolute ethyl alcohol according to a mass ratio of 1.05;
filling the secondary aluminum nitride powder taken out of the dryer into a powder mixer of a vibrating fluidized bed, and controlling the filling coefficient of the powder to be 40%; introducing the diluent of the coating agent into a sprayer, starting a container moving type powder mixer, spraying, setting the spraying air pressure to control the size of atomized liquid drops to be 10 micrometers, setting the distance from a nozzle to a material to be 20cm, and setting the spraying angle to be 60 degrees; in the spraying process, the using amount of the coating agent is 2wt% of the mass of the secondary aluminum nitride powder;
adjusting the frequency of a vibration exciter in the operation process of the powder mixer of the vibrating fluidized bed to control the maximum movement speed of powder to be 5m/s when the coating agent is mixed with the powder; the temperature during mixing is controlled to be 60 ℃, and the mixing time is 2 hours;
after mixing, conveying the mixture to an airflow dryer for drying at the drying temperature of 80 ℃ for 2 hours to obtain secondary coated modified aluminum nitride powder;
the two-stage coated modified aluminum nitride powder is characterized in that: d 50 The grain diameter is 8.5 mu m, the effective grafting ratio of the coating agent of the coating layer is 0.8 percent, and the surface energy is 24mJ/m 2 The comparative D50 particle size change rate before and after coating was 6.25%, and the unreacted coating agent residual rate was 500ppm.
(1.3) coating modification of the three-level aluminum nitride powder, which comprises the following specific steps:
d of three-stage aluminum nitride powder 50 The grain diameter is 95 mu m, the oxygen element content is 0.7wt%, the carbon element content is 0.1wt%, the sphericity is 96%, and the true density is 3.28g/cm 3 Specific surface area 0.02m 2 (iv) g; putting the three-stage aluminum nitride powder in a dryer for placing>The water content of the powder is 0.05 percent after 24 hours;
the coating agent is silane oligomer with the number average molecular weight of 600 and the reaction degree of 1%; mixing the coating agent, water and ethanol according to a mass ratio of 1.2;
filling the three-stage aluminum nitride powder taken out of the dryer into a container moving type three-dimensional powder mixer, and controlling the filling coefficient of the powder to be 40%; introducing the diluent of the coating agent into a sprayer, starting a mechanical paddle powder mixer, spraying, setting the spraying air pressure to control the size of atomized liquid drops to be 20 micrometers, setting the distance between a nozzle and the material to be 30cm, and setting the spraying angle to be 60 degrees; in the spraying process, the using amount of the coating agent diluent is 1.5 percent of the mass of the third-level aluminum nitride powder;
in the operation process of the container moving type three-dimensional powder mixer, the rotating speed of the powder container movement is adjusted to control the maximum movement speed of the powder to be 10m/s when the coating agent is mixed with the powder; the temperature during mixing is controlled to be 100 ℃, and the mixing time is 1h;
after the mixing is finished, conveying the mixture to an infrared dryer for drying at the drying temperature of 100 ℃ for 5 hours to obtain three-stage coated modified aluminum nitride powder;
the three-level coated modified aluminum nitride powder is characterized in that: d 50 The grain diameter is 100 mu m, the effective grafting ratio of the coating agent of the coating layer is 0.5 percent, and the surface energy is 22mJ/m 2 The residual rate of the unreacted coating agent was 2000ppm.
(2) Applying the modified aluminum nitride prepared in the step (1) to the preparation of the heat-conducting gel, and specifically comprises the following steps:
will D 50 Mixing alumina with the grain diameter of 0.5 mu m and the primary coating modified aluminum nitride powder in a volume ratio of 4; d 50 The volume ratio of the alumina with the grain diameter of 3 mu m to the second-stage coated modified aluminum nitride powder is 1; the primary filler powder, the secondary filler powder and the three-level coated modified aluminum nitride powder are respectively batched according to the volume ratio of 1 2 Mixing the component A and the component B; the component A comprises vinyl silicone oil and Karstedt catalyst (the content of the catalyst is 1wt% of the mass of the vinyl silicone oil), the component B is a mixture of the vinyl silicone oil and hydrogen-containing silicone oil, and the molar ratio of the vinyl group of the vinyl silicone oil to the hydrosil group of the hydrogen-containing silicone oil is 1; the mixing equipment is 1L double planetary mixer with dispersion and paddle rotation speed>60rpm, mixing time>1h; after mixing, vacuumizing to-98 kPa to obtain AB bi-component heat-conducting gel;
the heat-conducting gel is characterized in that: the heat conductivity coefficient of the AB adhesive after mixing and curing according to the volume ratio of 1; the extrusion speed is more than 4g/min under 90psi by using a 50ccEDF twin-tire dispensing tube matched with a 21-joint static mixer, the flow speed is attenuated by less than 5% after continuous dispensing for 24 hours, and the extrusion speed is attenuated by less than 10% in the storage period of 6 months.
Comparative example 1
(1) According to D 50 The aluminum nitride powder is divided into three stages according to different particle diameters, and is coated and modified, and the aluminum nitride powder coating specifically comprises the following components:
(1.1) coating modification of the primary aluminum nitride powder, which comprises the following specific steps:
d of first-order aluminum nitride powder 50 The particle diameter was 1.9 μm, the oxygen content was 0.78wt%, the carbon content was 0.3wt%, the sphericity was 90%, and the true density was 3.28g/cm 3 Specific surface area of 2.5m 2 (iv) g; placing the first-stage aluminum nitride powder body in a dryer>After 24 hours, the water content of the powder is 0.1%;
coating agent selection C 10 Alkyl triethoxy silane, the reaction degree is 2%; mixing the coating agent, water and absolute ethyl alcohol according to a mass ratio of 1;
filling the primary aluminum nitride powder taken out of the dryer into a pneumatic mixer, and controlling the filling coefficient of the powder to be 50%; introducing the diluent of the coating agent into a sprayer, starting a fluidized bed powder mixer, spraying, setting the spraying air pressure to control the size of atomized liquid drops to be 5 micrometers, setting the distance from a nozzle to a material to be 20cm, and setting the spraying angle to be 60 degrees; in the spraying process, the amount of the coating agent is 3wt% of the mass of the first-level aluminum nitride powder;
during the operation of the pneumatic mixer, the air consumption and the pressure of the powder mixer are adjusted to control the maximum movement speed of the powder to be 20m/s when the coating agent is mixed with the powder; the temperature during mixing is controlled to be 50 ℃, and the mixing time is 3h;
after mixing, conveying the mixture to an airflow dryer for drying at the temperature of 130 ℃ for 0.5h to obtain first-stage coated modified aluminum nitride powder;
the first-level coating modified powder is characterized in that: d 50 The grain diameter is 2 mu m, the effective grafting rate of the coating agent of the coating layer is 2 percent, and the surface energy is 30mJ/m 2 The residual ratio of the unreacted coating agent was 100ppm.
(1.2) coating modification of secondary aluminum nitride powder, which comprises the following specific steps:
d of second-grade aluminum nitride powder 50 The grain diameter is 8 μm, the oxygen content is 0.7wt%, the carbon content is 0.2%, the sphericity is 85%, and the true density is 3.28g/cm 3 Specific surface area of 0.4m 2 (ii)/g; placing the secondary aluminum nitride powder in a dryer>After 24 hours, the water content of the powder is 0.1%;
coating agent selection C 10 Alkyl triethoxysilane, degree of reaction 2%; mixing the coating agent, water and absolute ethyl alcohol according to a mass ratio of 1;
filling the second-stage aluminum nitride powder taken out of the dryer into a pneumatic mixer, and controlling the filling coefficient of the powder to be 50%; introducing the diluent of the coating agent into a sprayer, starting a fluidized bed powder mixer, spraying, setting the spraying air pressure to control the size of atomized liquid drops to be 5 micrometers, setting the distance from a nozzle to a material to be 20cm, and setting the spraying angle to be 60 degrees; in the spraying process, the using amount of the coating agent is 3wt% of the mass of the secondary aluminum nitride powder;
adjusting the gas consumption and pressure of the powder mixer during the operation of the pneumatic mixer to control the maximum movement speed of the powder to be 20m/s when the coating agent is mixed with the powder; the temperature during mixing is controlled to be 50 ℃, and the mixing time is 3h;
after the mixing is finished, conveying the mixture to an airflow dryer for drying at the temperature of 130 ℃ for 0.5h to obtain secondary coated modified aluminum nitride powder;
the two-stage coated modified aluminum nitride powder is characterized in that: d 50 The grain diameter is 12 mu m, the effective grafting rate of the coating agent of the coating layer is 2 percent, and the surface energy is 24mJ/m 2 The D50 particle size change ratio before and after coating was 50%, and the unreacted coating agent residual ratio was 50000ppm.
(1.3) coating modification of the three-level aluminum nitride powder, which comprises the following specific steps:
d of three-stage aluminum nitride powder 50 The grain diameter is 95 mu m, the oxygen element content is 0.7wt%, the carbon element content is 0.1wt%, the sphericity is 96%, and the true density is 3.28g/cm 3 Specific surface area of 0.02m 2 (iv) g; placing the three-stage aluminum nitride powder body in a dryer>The water content of the powder is controlled to be 0.1 percent after 24 hours
Coating agent selection C 10 Alkyl triethoxy silane, the reaction degree is 2%; mixing the coating agent, water and absolute ethyl alcohol according to a mass ratio of 1;
filling the three-stage aluminum nitride powder taken out of the dryer into a pneumatic mixer, and controlling the filling coefficient of the powder to be 50%; introducing the diluent of the coating agent into a sprayer, starting a fluidized bed powder mixer, spraying, setting the spraying air pressure to control the size of atomized liquid drops to be 5 micrometers, setting the distance from a nozzle to a material to be 20cm, and setting the spraying angle to be 60 degrees; in the spraying process, the using amount of the coating agent is 3wt% of the mass of the three-level aluminum nitride powder;
during the operation of the pneumatic mixer, the air consumption and the pressure of the powder mixer are adjusted to control the maximum movement speed of the powder to be 20m/s when the coating agent is mixed with the powder; the temperature during mixing is controlled to be 50 ℃, and the mixing time is 3h;
after mixing, conveying the mixture to an airflow dryer for drying at the temperature of 130 ℃ for 0.5h to obtain three-level coated modified aluminum nitride powder;
the three-level coated modified aluminum nitride powder is characterized in that: d 50 The grain diameter is 120 mu m, the effective grafting rate of the coating agent of the coating layer is 1 percent, and the surface energy is 22mJ/m 2 The residual ratio of the unreacted coating agent was 20000ppm.
(2) Applying the modified aluminum nitride prepared in the step (1) to the preparation of the heat-conducting gel, and specifically comprises the following steps:
will D 50 Mixing alumina with the grain diameter of 0.5 mu m and the primary coating modified aluminum nitride powder in a volume ratio of 4; d 50 The volume ratio of the alumina with the grain diameter of 3 mu m to the second-stage coated modified aluminum nitride powder is 1; the primary filler powder, the secondary filler powder and the three-level coated modified aluminum nitride powder are respectively batched according to the volume ratio of 1 2 Mixing the component A and the component B; the component A comprises vinyl silicone oil and Karstedt catalyst (the content of the catalyst is 1wt% of the mass of the vinyl silicone oil), the component B is a mixture of the vinyl silicone oil and hydrogen-containing silicone oil, and the molar ratio of the vinyl group of the vinyl silicone oil to the hydrosil group of the hydrogen-containing silicone oil is 1; the mixing equipment is 1L double planetary mixer with dispersion and paddle rotation speed>60rpm, mixing time>1h; after mixing, vacuumizing to-98 kPa to obtain AB bi-component heat-conducting gel;
the heat-conducting gel is characterized in that: the heat conductivity coefficient of the AB adhesive after mixing and curing according to the volume ratio of 1; under 90psi, a 50ccEDF twin-carcass dispensing tube is matched with a 21-section static mixer, the extrusion speed is 1.5g/min, the flow speed is reduced by 15 percent after 24 hours of continuous dispensing, and the extrusion speed is reduced by 20 percent within 6 months of storage period.
The foregoing is only a preferred embodiment of the present invention, and it should be noted that, for those skilled in the art, various modifications and decorations can be made without departing from the principle of the present invention, and these modifications and decorations should also be regarded as the protection scope of the present invention.
Claims (10)
1. The application of the coated modified aluminum nitride powder is characterized in that the coated modified aluminum nitride powder is used as a heat-conducting filler for preparing a thermal interface material;
the coated modified aluminum nitride powder is one or more of a coated modified aluminum nitride powder A, a coated modified aluminum nitride powder B and a coated modified aluminum nitride powder C prepared by the following method:
according to D 50 The method is characterized in that differential coating modification is carried out on aluminum nitride powder according to different particle sizes, and specifically comprises the following steps:
a) For D 50 The aluminum nitride powder with the grain diameter less than 2 mu m is coated and modified according to the following method:
dynamically mixing aluminum nitride powder and a coating agent diluent in a powder mixer, and then reacting and drying to obtain coated modified aluminum nitride powder A;
in the step a), the water content of the aluminum nitride powder is 0.1-5%; the filling coefficient of the aluminum nitride powder in the powder mixer is 50-80%; the components of the coating agent diluent comprise a coating agent and a solvent; the mass ratio of the coating agent to the solvent is 1: (1-5); the using amount of the coating agent is 0.5-5% of the mass of the aluminum nitride powder; spraying the diluent of the coating agent into a powder mixer in a spraying mode to participate in dynamic mixing; in the spraying process, the diameter of the atomized liquid drop is 1-30 μm; in the dynamic mixing process, the maximum movement speed of the aluminum nitride powder is 10-60 m/s;
b) For D 50 The aluminum nitride powder with the grain diameter of 2-10 mu m is coated and modified according to the following method:
dynamically mixing aluminum nitride powder and a coating agent diluent in a powder mixer, and then reacting and drying to obtain coated modified aluminum nitride powder B;
in the step b), the water content of the aluminum nitride powder is 0.1-3%; the filling coefficient of the aluminum nitride powder in the powder mixer is 30-70%; the components of the coating agent diluent comprise a coating agent and a solvent; the mass ratio of the coating agent to the solvent is 1: (0.5 to 5); the dosage of the coating agent is 0.5 to 4 percent of the mass of the aluminum nitride powder; spraying the diluent of the coating agent into a powder mixer in a spraying mode to participate in dynamic mixing; in the spraying process, the diameter of the atomized liquid drop is 1-30 mu m; in the dynamic mixing process, the maximum movement speed of the aluminum nitride powder is 5-30 m/s;
c) For D 50 The aluminum nitride powder with the grain diameter larger than 10 mu m is coated and modified according to the following method:
dynamically mixing aluminum nitride powder and a coating agent diluent in a powder mixer, and reacting and drying to obtain coated modified aluminum nitride powder C;
in the step c), the water content of the aluminum nitride powder is 0.05-3%; the filling coefficient of the aluminum nitride powder in the powder mixer is 20-60%; the components of the coating agent diluent comprise a coating agent and a solvent; the mass ratio of the coating agent to the solvent is 1: (0.5 to 5); the using amount of the coating agent is 0.5 to 3 percent of the mass of the aluminum nitride powder; the coating agent diluent is sprayed into the powder mixer in a spraying mode to participate in dynamic mixing; in the spraying process, the diameter of the atomized liquid drop is 1-30 μm; in the dynamic mixing process, the maximum movement speed of the aluminum nitride powder is 2-15 m/s.
2. The application of claim 1, wherein the coated modified aluminum nitride powder is compounded with other heat-conducting fillers to be used as the heat-conducting filler for preparing the thermal interface material.
3. A coating modification method of aluminum nitride powder, which is characterized in that the coating modification method is according to D 50 The method for performing differential coating modification on aluminum nitride powder according to different particle sizes specifically comprises the following steps:
a) For D 50 The aluminum nitride powder with the grain diameter less than 2 mu m is coated and modified according to the following method:
dynamically mixing aluminum nitride powder and a coating agent diluent in a powder mixer, and reacting and drying to obtain coated modified aluminum nitride powder A;
in the step a), the water content of the aluminum nitride powder is 0.1-5%; the filling coefficient of the aluminum nitride powder in the powder mixer is 50-80%; the components of the coating agent diluent comprise a coating agent and a solvent; the mass ratio of the coating agent to the solvent is 1: (1-5); the using amount of the coating agent is 0.5-5% of the mass of the aluminum nitride powder; the coating agent diluent is sprayed into the powder mixer in a spraying mode to participate in dynamic mixing; in the spraying process, the diameter of the atomized liquid drop is 1-30 mu m; in the dynamic mixing process, the maximum movement speed of the aluminum nitride powder is 10-60 m/s;
b) For D 50 The aluminum nitride powder with the grain diameter of 2-10 mu m is coated and modified according to the following method:
dynamically mixing aluminum nitride powder and a coating agent diluent in a powder mixer, and then reacting and drying to obtain coated modified aluminum nitride powder B;
in the step b), the water content of the aluminum nitride powder is 0.1-3%; the filling coefficient of the aluminum nitride powder in the powder mixer is 30-70%; the components of the coating agent diluent comprise a coating agent and a solvent; the mass ratio of the coating agent to the solvent is 1: (0.5 to 5); the dosage of the coating agent is 0.5 to 4 percent of the mass of the aluminum nitride powder; spraying the diluent of the coating agent into a powder mixer in a spraying mode to participate in dynamic mixing; in the spraying process, the diameter of the atomized liquid drop is 1-30 mu m; in the dynamic mixing process, the maximum movement speed of the aluminum nitride powder is 5-30 m/s;
c) For D 50 The aluminum nitride powder with the grain diameter larger than 10 mu m is coated and modified according to the following method:
dynamically mixing aluminum nitride powder and a coating agent diluent in a powder mixer, and then reacting and drying to obtain coated modified aluminum nitride powder C;
in the step c), the water content of the aluminum nitride powder is 0.05-3%; the filling coefficient of the aluminum nitride powder in the powder mixer is 20-60%; the components of the coating agent diluent comprise a coating agent and a solvent; the mass ratio of the coating agent to the solvent is 1: (0.5-5); the using amount of the coating agent is 0.5 to 3 percent of the mass of the aluminum nitride powder; the coating agent diluent is sprayed into the powder mixer in a spraying mode to participate in dynamic mixing; in the spraying process, the diameter of the atomized liquid drop is 1-30 μm; in the dynamic mixing process, the maximum movement speed of the aluminum nitride powder is 2-15 m/s.
4. The coating modification method of claim 3, wherein D is 50 The sphericity of the aluminum nitride powder with the grain diameter less than 2 mu m is more than or equal to 80 percent, the oxygen element content is 0.1 to 0.8 weight percent, the carbon element content is 0.01 to 0.4 weight percent, and the specific surface area is 1 to 3.2m 2 G, true density of 3.2-3.3 g/cm 3 ；
Said D 50 The sphericity of the aluminum nitride powder with the grain diameter of 2-10 mu m is more than or equal to 85 percent, the oxygen element content is 0.1-0.9 wt percent, the carbon element content is 0.01-0.4 wt percent, and the specific surface area is 0.2-1.5 m 2 G, true density of 3.2-3.3 g/cm 3 ；
Said D 50 The sphericity of the aluminum nitride powder with the grain diameter more than 10 mu m is more than or equal to 90 percent, the oxygen element content is 0.1 to 1 weight percent, the carbon element content is 0.01 to 0.2 weight percent, and the specific surface area is 0.01 to 0.5m 2 G, the real density is 3.2-3.3 g/cm 3 。
5. The coating modification method according to claim 3, characterized in that in steps a) to c), the coating agent is a silane oligomer and/or an organosilicon compound containing alkoxy groups;
in the step a), the reaction degree of the coating agent is less than or equal to 5 percent; in the step b), the reaction degree of the coating agent is less than or equal to 10 percent; in the step c), the reaction degree of the coating agent is less than or equal to 10 percent.
6. The coating modification method according to claim 3, wherein in steps a) to c), the solvent is one or more of water, alcohol and petroleum hydrocarbon.
7. The coating modification method according to claim 3, wherein in the spraying in steps a) to c), the distance from the nozzle to the material is 10 to 50cm, and the spraying angle is 30 to 120 °.
8. The coating modification method according to claim 3, wherein in steps a) -c), the temperature of the dynamic mixing is 50-150 ℃; the time of the dynamic mixing is 1-24 h.
9. The coating modification method according to claim 3, wherein in the steps a) to c), the drying temperature is 80 to 200 ℃; the drying time is 0.5-8 h.
10. The coating modification method according to claim 3, wherein in the step a), the surface energy of the coating-modified aluminum nitride powder A is 20 to 30mJ/m 2 The effective grafting rate of the coating agent is 0.3-5%, and D is before and after coating 50 The change rate of the grain diameter is less than or equal to 150 percent, and the residual rate of the unreacted coating agent is less than or equal to 2000ppm;
in the step B), the surface energy of the coated modified aluminum nitride powder B is 18-26 mJ/m 2 The effective grafting rate of the coating agent is 0.2-4%, and D is before and after coating 50 The change rate of the particle size is less than or equal to 100 percent, and the residual rate of the unreacted coating agent is less than or equal to 2000ppm;
in the step C), the surface energy of the coated modified aluminum nitride powder C is 18-24 mJ/m 2 The effective grafting rate of the coating agent is 0.11-3%, and D is before and after coating 50 The change rate of the grain diameter is less than or equal to 30 percent, and the residual rate of the unreacted coating agent is less than or equal to 2000ppm.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202211070665.0A CN115637063B (en) | 2022-09-02 | 2022-09-02 | Coating modification method of aluminum nitride powder and application thereof |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202211070665.0A CN115637063B (en) | 2022-09-02 | 2022-09-02 | Coating modification method of aluminum nitride powder and application thereof |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| CN115637063A true CN115637063A (en) | 2023-01-24 |
| CN115637063B CN115637063B (en) | 2024-05-28 |
Family
ID=84939581
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN202211070665.0A Active CN115637063B (en) | 2022-09-02 | 2022-09-02 | Coating modification method of aluminum nitride powder and application thereof |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN115637063B (en) |
Citations (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN103497739A (en) * | 2013-10-09 | 2014-01-08 | 中国科学院深圳先进技术研究院 | Heat transfer paste and preparation method thereof |
| CN108084742A (en) * | 2017-11-22 | 2018-05-29 | 纳琳威纳米科技南通有限公司 | A kind of preparation method and purposes of the high heat conduction aluminium nitride dispersion liquid that insulate |
| CN110088039A (en) * | 2017-03-07 | 2019-08-02 | 株式会社德山 | Aluminium nitride powder without oversize grain |
| CN110628223A (en) * | 2019-11-01 | 2019-12-31 | 银川艾森达新材料发展有限公司 | Heat-conducting filler |
| CN111303488A (en) * | 2020-03-23 | 2020-06-19 | 东莞理工学院 | Modified heat-conducting filler and preparation method thereof |
| CN112585087A (en) * | 2018-08-24 | 2021-03-30 | 昭和电工株式会社 | Method for producing silicon-oxide-coated aluminum nitride particles, and silicon-oxide-coated aluminum nitride particles |
-
2022
- 2022-09-02 CN CN202211070665.0A patent/CN115637063B/en active Active
Patent Citations (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN103497739A (en) * | 2013-10-09 | 2014-01-08 | 中国科学院深圳先进技术研究院 | Heat transfer paste and preparation method thereof |
| CN110088039A (en) * | 2017-03-07 | 2019-08-02 | 株式会社德山 | Aluminium nitride powder without oversize grain |
| CN108084742A (en) * | 2017-11-22 | 2018-05-29 | 纳琳威纳米科技南通有限公司 | A kind of preparation method and purposes of the high heat conduction aluminium nitride dispersion liquid that insulate |
| CN112585087A (en) * | 2018-08-24 | 2021-03-30 | 昭和电工株式会社 | Method for producing silicon-oxide-coated aluminum nitride particles, and silicon-oxide-coated aluminum nitride particles |
| CN110628223A (en) * | 2019-11-01 | 2019-12-31 | 银川艾森达新材料发展有限公司 | Heat-conducting filler |
| CN111303488A (en) * | 2020-03-23 | 2020-06-19 | 东莞理工学院 | Modified heat-conducting filler and preparation method thereof |
Also Published As
| Publication number | Publication date |
|---|---|
| CN115637063B (en) | 2024-05-28 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| CN109266187B (en) | Heat dissipation coating containing isocyanate modified graphene and preparation method thereof | |
| CN113248931A (en) | Heat-conducting gel with high heat conductivity and high extrusion rate and preparation method thereof | |
| JP2012020900A (en) | Spherical alumina powder, and method of production and application thereof | |
| CN104610849A (en) | Heat-conducting insulating coating for electronic components and preparation method thereof | |
| TWI414572B (en) | Use of nanomaterials in secondary electrical insulation coatings | |
| WO2020179662A1 (en) | Hexagonal boron nitride powder, resin composition, resin sheet, and method for producing hexagonal boron nitride powder | |
| JP2020073626A (en) | Inorganic particle dispersion resin composition and method for producing inorganic particle dispersion resin composition | |
| JP2018159012A (en) | Heat-radiating filler and heat-radiating resin composition containing the same | |
| CN115637063A (en) | Coating modification method of aluminum nitride powder and application thereof | |
| CN109351963A (en) | A kind of blacker-than-black material and its preparation method and application | |
| JP3473146B2 (en) | Composition for forming conductive film and method for producing transparent conductive film-coated glass plate | |
| WO2022202583A1 (en) | Inorganic oxide powder, resin composition, and compression molded article | |
| TWI488927B (en) | Method of manufacturing hydrophobic antifouling coating material and method of forming hydrophobic antifouling coating film | |
| CN111732871B (en) | Light high-heat-resistance coating and preparation method thereof | |
| JP2021084814A (en) | Surface-treated boron nitride production method, surface-treated boron nitride, resin composition, and cured product | |
| CN115322577B (en) | Heat-conducting gel and preparation method thereof | |
| CN115093826B (en) | High-heat-conductivity low-specific gravity adhesive and preparation method thereof | |
| CN108929650A (en) | A kind of two-component bonding nylon silica gel and preparation method | |
| WO2022202584A1 (en) | Inorganic oxide powder, resin composition, and compression-molded article | |
| KR100477200B1 (en) | Method to manufacture silica powder using ultrasonic aerosol pyrolysis | |
| TWI782209B (en) | Method for producing surface-treated aluminum nitride, surface-treated aluminum nitride, resin composition, and cured product | |
| KR102575326B1 (en) | Near-infrared absorbing material particle dispersion, near-infrared absorber, near-infrared absorber laminate, and bonded structure for near-infrared absorption | |
| CN112961391A (en) | Preparation method of transparent polyimide film containing modified silicon dioxide coating | |
| CN106987026B (en) | A kind of modified calcium carbonate and preparation method thereof, application | |
| CN115490863B (en) | High-temperature-resistant organic silicon elastomer and preparation method thereof |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| PB01 | Publication | ||
| PB01 | Publication | ||
| SE01 | Entry into force of request for substantive examination | ||
| SE01 | Entry into force of request for substantive examination | ||
| GR01 | Patent grant | ||
| GR01 | Patent grant |