Method for simultaneously producing nano-spherical oxide fillers and sub-micron-spherical oxide fillers

Abstract

The present invention relates to the technical field of spherical oxide fillers and provides a method for simultaneously producing nano- and submicron-sized spherical oxide fillers. In this invention, an oxide raw material (raw material O) is combined with a metal or non-metal raw material (raw material M), thereby reducing the reactivity of the raw material and reducing the risk of uncontrollable dust explosions, thereby achieving safe production. At the same time, raw material O is vaporized under high-temperature conditions to form nano-sized particles, or is dispersed into nano-sized particles by the shock waves generated by deflagration. Raw material M reacts with oxygen in an oxygen-rich environment, forming submicron-sized particles through aggregation and cooling. The resulting product particles are cooled in an oxygen-rich environment and then subjected to a fine separation step, thereby simultaneously obtaining submicron-sized and nano-sized spherical oxide fillers. Furthermore, in this invention, after the temperature in the reactor stabilizes, fuel gas consumption can be minimized, thereby stabilizing the temperature in the reactor and reducing costs.

Description

[Technical Field]

[0001] [CROSS-REFERENCE TO RELATED APPLICATIONS] This application claims priority to a Chinese patent application filed with the China Patent Office on October 18, 2022, bearing application number CN202211271930.1 and entitled "Method for simultaneously producing nano- and submicron-spherical oxide fillers," the entire contents of which are incorporated herein by reference.

[0002] The present invention relates to the technical field of spherical oxide fillers, and more particularly to a method for simultaneously producing nano-spherical oxide fillers and sub-micron-spherical oxide fillers. [Background technology]

[0003] Adding fillers to electronic packaging devices improves the system's performance, such as its coefficient of thermal expansion, dielectric properties, moisture resistance, and stress. However, in recent years, electronic devices have become thinner, lighter, and smaller, which requires smaller filler particle sizes, making it essential to reduce the particle size of fillers.

[0004] Currently, the main methods for producing nano and submicron fillers include liquid phase synthesis, plasma synthesis, vaporization, and flame synthesis. Liquid phase synthesis uses organic solvents that are environmentally unfriendly, expensive, and have long production cycles, making it difficult to mass-produce cost-effective products. Plasma synthesis is a physical process, which has high operating costs and low production capacity, making large-scale production difficult. Vaporization is a method of obtaining submicron products using high-temperature focusing of a light source such as a laser, but this method is still in the development stage and the produced products are not stable. Flame synthesis is currently one of the main methods for producing spherical oxide fillers. In this method, the filler is introduced into a high-temperature environment formed by flammable gas - oxygen, where it melts at high temperature. After cooling, it becomes spherical due to the action of surface tension, ultimately forming spherical oxide fillers.

[0005] A US patent document issued in 1990 (patent number: US4923520) proposed a method of forming a high-temperature flame using propane, a flammable gas, and oxygen, a combustion support, and using that flame to spheroidize rectangular silica powder, but this method could only produce products with an average particle size of 10μm to 50μm. After continuous improvements, the actual manufacturing process now produces products with an average particle size of approximately 3μm, but this method still cannot produce products with an average particle size of less than 3μm.

[0006] In addition, a document published by Admatechs Co., Ltd. (JP 2009-263154) uses silicon as a raw material and utilizes the principle of dust explosion to produce a powder with an average particle size of 0.5 μm and a specific surface area of ​​6.0 m 2 In a patent document published by Shin-Etsu Chemical (Patent Publication No. 4-132610), silicon powder was combusted in an oxygen-containing stream to obtain spherical silica powder with an average particle size of 0.1 to 10 μm. However, considering that silicon is used as the raw material, metals are prone to dust explosions under high temperature and oxygen-rich conditions, which are detrimental to factory design, equipment, and personnel safety, this process is rarely used in China to produce submicron silicon oxide products.

[0007] Therefore, there is currently a need in this field for a safe method for simultaneously producing nano-spherical oxide fillers and sub-micron-spherical oxide fillers. Summary of the Invention [Problem to be solved by the invention]

[0008] In view of this situation, the present invention provides a method for simultaneously producing nano- and submicron-spherical oxide fillers. The method provided by the present invention can simultaneously produce nano- and submicron-spherical oxide fillers, and is safe. [Means for solving the problem]

[0009] In order to achieve the above object of the present invention, the present invention provides the following technical solutions: A method for simultaneously producing nano-spherical oxide fillers and sub-micron-spherical oxide fillers, obtaining combustion products by subjecting a first raw material and a second raw material to a combustion reaction in the presence of a fuel gas and a combustion-supporting gas, wherein the first raw material is a metal element powder, a non-metal element powder, or an alloy powder, the second raw material is an oxide or a composite oxide corresponding to the first raw material, the particle size of the first raw material is 3 to 300 μm, the particle size of the second raw material is 30 nm to 10 μm, and the mass of the second raw material is 30% or less of the total mass of the first raw material and the second raw material; cooling the combustion products and then subjecting the cooled combustion products to precision separation to obtain submicron spherical oxide fillers and nano-spherical oxide fillers.

[0010] Preferably, during the combustion reaction, the first and second raw materials are mixed together before being supplied, and the mixing is dry mixing or liquid phase mixing.

[0011] Preferably, the liquid phase mixing is performed by mixing the first raw material, the second raw material and a solvent, and then drying the mixture to obtain a mixed powder.

[0012] Preferably, the solvent is one or more of water, methanol, ethanol, acetone, and butanone, the drying temperature is 100° C. to 200° C., and the drying time is 2 hours to 30 hours.

[0013] Preferably, the equipment used for the dry mixing includes a V-mixer, a double cone mixer, a pneumatic mixer, a cone mixer, a high speed mixer or an airflow mixer.

[0014] Preferably, when the first and second raw materials are mixed and then fed, the feeding rate is 1.7 g / min to 1020 g / min.

[0015] Preferably, when a first raw material and a second raw material are supplied during the combustion reaction, the supply rate of the first raw material is 1.7 g / min to 700 g / min, and the supply rate of the second raw material is 250 g / min or less.

[0016] Preferably, in the combustion reaction, after the temperature in the reactor is stabilized, the fuel gas introduction rate is reduced to 2% to 10% of the initial introduction rate, and the temperature is considered to be stabilized when the fluctuation in the temperature in the reactor does not exceed 10°C.

[0017] Preferably, the initial introduction velocity of the fuel gas is 50 m 3 / h, and after the temperature in the reactor stabilized, the fuel gas introduction rate was increased to 2 m 3 / h.

[0018] Preferably, the metal element powder includes one or more of aluminum, magnesium, iron, copper, titanium, zirconium, and zinc, the non-metal element powder is silicon, and the alloy powder is one or more of aluminum-iron alloy, aluminum-silicon alloy, aluminum-magnesium alloy, magnesium alloy, and silicon-iron alloy powder.

[0019] Preferably, the method of precision separation includes one or more of cyclone classification, air classification, overflow classification and sieve classification.

[0020] Preferably, the D of the submicron spherical oxide filler 50 The particle size is 0.1 μm to 1.5 μm, and the D of the nano-spherical oxide filler 50 The particle size is 10 nm to 100 nm.

[0021] Preferably, the fuel gas comprises one or more of hydrogen, liquefied natural gas, liquefied petroleum gas, acetylene and propane, and the combustion supporting gas comprises one or two of oxygen and air. [Effects of the Invention]

[0022] The present invention provides a method for simultaneously producing nano- and submicron-sized spherical oxide fillers, comprising the following steps: Combustion reaction of a first raw material and a second raw material in the presence of a fuel gas and a combustion-supporting gas to obtain combustion products, the first raw material being a powder of an elemental metal, a non-metallic elemental metal, or an alloy, and the second raw material being an oxide or composite oxide corresponding to the first raw material; The combustion products are then cooled and precisely separated to obtain submicron-sized spherical oxide fillers and nano-sized spherical oxide fillers. In this invention, the oxide raw material (second raw material, hereinafter referred to as raw material O) is combined with a metal or non-metallic raw material (first raw material, hereinafter referred to as raw material M) to reduce the reactivity of the resulting mixed raw material (hereinafter referred to as raw material MO), thereby reducing the risk of uncontrolled dust explosions and achieving safe production. At the same time, raw material O is vaporized under high temperature conditions to form nano-sized particles, or is dispersed into nano-sized particles by the shock waves generated by deflagration. Raw material M reacts with oxygen in an oxygen-enriched state, agglomerates, and cools to form submicron-sized particles. The product particles obtained from the combustion reaction are cooled at high temperatures and in an oxygen-rich environment, and become spherical due to the action of surface tension, with raw materials M and O forming submicron-scale particles and nano-scale particles, respectively. The mixed particles then undergo a precision separation step, allowing submicron spherical oxide fillers and nano-spherical oxide fillers to be obtained simultaneously.

[0023] Furthermore, raw material M reacts with oxygen to release a large amount of heat, which can support subsequent reactions. Therefore, in the present invention, after the temperature in the reactor is stabilized, the fuel gas can be minimized, thereby stabilizing the temperature in the reactor and reducing costs. DETAILED DESCRIPTION OF THE INVENTION

[0024] The present invention provides a method for simultaneously producing nano- and submicron-spherical oxide fillers, comprising the steps of: a first raw material and a second raw material are subjected to a combustion reaction in the presence of a fuel gas and a combustion-supporting gas to obtain a combustion product, the first raw material being a metal element powder, a non-metal element powder, or an alloy powder, the second raw material being an oxide or a composite oxide corresponding to the first raw material, the particle size of the first raw material being 3 to 300 μm, the particle size of the second raw material being 30 nm to 10 μm, and the mass of the second raw material being 30% or less of the total mass of the first raw material and the second raw material, After cooling the combustion products, they are precision separated to obtain submicron spherical oxide fillers and nano-spherical oxide fillers.

[0025] In the present invention, a first raw material and a second raw material are combusted in the presence of a fuel gas and a combustion-supporting gas to obtain combustion products. In the present invention, the first raw material is a metal powder, a nonmetal powder, or an alloy powder. The metal powder preferably includes one or more of aluminum, magnesium, iron, copper, titanium, zirconium, and zinc. The nonmetal powder is preferably silicon. The alloy powder preferably includes one or more of aluminum-iron alloy, aluminum-silicon alloy, aluminum-magnesium alloy, magnesium alloy, and silicon-iron alloy powder. The second raw material is an oxide corresponding to the first raw material. For example, if the first raw material is aluminum powder (Al), the second raw material is aluminum oxide powder (Al2O3). If the first raw material is silicon powder (Si), the second raw material is silicon oxide powder (SiO2). If the first raw material is an aluminum-silicon alloy, the second raw material is a mixture of aluminum oxide powder and silicon oxide powder (i.e., a composite oxide). In the present invention, the first raw material is referred to as raw material M, the second raw material is referred to as raw material O, and a mixture of the first raw material and the second raw material is referred to as raw material MO.

[0026] In the present invention, the average particle size of the raw material M is 3 μm to 300 μm, specifically 3 μm, 5 μm, 15 μm, 35 μm, 50 μm, 100 μm, 200 μm, or 300 μm, and the average particle size of the raw material O is 30 nm to 10 μm, specifically 30 nm, 100 nm, 1 μm, 3 μm, 5 μm, or 10 μm.

[0027] In the present invention, the mass of the raw material O is 30% or less of the total mass of raw materials M and O, specifically, greater than 0 and 30% or less, preferably 5% to 25%, and more preferably 10% to 20%.

[0028] In the present invention, the method for supplying the first and second raw materials during the combustion reaction is preferably a method in which raw materials M and O are mixed and then supplied, or a method in which raw materials M and O are supplied separately. When the method of mixing and then supplying is adopted, the method for mixing raw materials M and O is preferably dry mixing or liquid-phase mixing. The dry mixing device includes a V-type mixer, a double cone mixer, a pneumatic mixer, a cone mixer, a high-speed mixer, or an airflow mixer. The liquid-phase mixing is preferably a method in which raw materials M, raw material O, and a solvent are mixed and then dried to obtain a mixed powder (i.e., raw material MO). The solvent preferably includes one or more of water, methanol, ethanol, acetone, and butanone. The device used for the liquid-phase mixing is preferably the same as the device used for dry mixing. After mixing is completed, the solvent can be completely removed by drying at 100°C to 200°C for 2 to 30 hours. In the present invention, there is no special requirement for the volume of the solvent used in the liquid-phase mixing process, as long as raw materials M and O can be uniformly mixed.

[0029] In a specific embodiment of the present invention, when the method of mixing and then feeding is adopted, the feed rate of the raw material MO is preferably 1.7 g / min to 1020 g / min.

[0030] In the present invention, when a method of separately supplying raw materials M and O is adopted, the raw materials (raw materials M and O) in different storage tanks are preferably transferred to the combustion reaction vessel at a constant speed, and the transfer speeds of raw materials M and O are controlled to control the mass of raw material O in the reaction vessel to 30% or less of the total mass of raw materials M and O. In a specific embodiment of the present invention, when a method of separately supplying raw materials M and O is adopted, the feed rate of raw material M is preferably 1.7 g / min to 700 g / min, and the feed rate of raw material O is preferably 250 g / min or less, preferably 0.5 g / min to 250 g / min.

[0031] In the present invention, the fuel gas preferably comprises one or more of hydrogen, liquefied natural gas, liquefied petroleum gas, acetylene, and propane. The supporting gas preferably comprises one or more of oxygen and air. The vessel used for the combustion reaction is preferably a reactor. In the present invention, preferably, the fuel gas and supporting gas are first passed through the reactor to be combusted, and then raw material MO is passed through, or raw material M and raw material O are passed through, respectively. The raw material MO reacts in the high-temperature flame formed by the fuel gas and supporting gas, and the raw material MO decomposes instantaneously under oxygen-rich and high-temperature conditions. The intermediate raw material M burns with oxygen, releasing a large amount of heat, resulting in a continuous rise in temperature. In the present invention, after the temperature in the reactor has stabilized, the present invention preferably reduces the fuel gas introduction rate to 2% to 10% of the initial introduction rate. In a specific embodiment of the present invention, the temperature in the reactor is considered stable when the temperature fluctuation in the reactor does not exceed 10°C. Through the above operation, the present invention can reduce the amount of fuel gas used, reduce costs, and control the temperature balance in the reactor. The introduction speed of the combustion-supporting gas is preferably calculated based on the stoichiometric ratio with the fuel gas. In a specific embodiment of the present invention, as the amount of fuel gas used decreases, the amount of combustion-supporting gas used also decreases. In a specific embodiment of the present invention, the initial introduction speed of the fuel gas is preferably 50 m 3 / h, and the initial introduction rate of the combustion-supporting gas is preferably 150 m 3 / h, and after the temperature in the reactor is stabilized, the fuel gas introduction rate is preferably 2 m 3 / h, the introduction speed of the combustion oxidizing gas is preferably 15m 3 / h.

[0032] In the combustion reaction process, raw material O is vaporized under high-temperature conditions to form nanoscale particles or is dispersed into nanoscale particles by the shock waves generated by deflagration, and raw material M reacts with oxygen in an oxygen-enriched state to form submicron-scale particles through aggregation and cooling, so that the resulting combustion product is a mixture of nanoscale oxide particles and submicron-scale oxide particles.

[0033] After obtaining the combustion products, the present invention cools the combustion products and then performs precision separation to obtain submicron spherical oxide fillers and nanospherical oxide fillers. In the present invention, the cooling is preferably performed by air cooling, and during the cooling process, the nano-scale particles and submicron-scale particles become spherical due to the action of surface tension, forming nanospherical oxide particles and submicron spherical oxide particles. In the present invention, the precision separation method preferably includes one or more of cyclone classification, air classification, overflow classification, and sieve classification. The present invention does not require specific operating conditions for the above methods; it is sufficient to separate products of different particle sizes using conditions well known to those skilled in the art. The precision-separated coarse powder portion is a submicron spherical oxide filler, and the fine powder portion is a nanospherical oxide filler. In the present invention, the average particle size of the submicron spherical oxide filler is 0.1 μm to 1.5 μm, and the average particle size of the nanospherical oxide filler is 10 nm to 100 nm.

[0034] The following examples of the present invention will be used to clearly and completely explain the technical solutions of the present invention, but the described examples are only some of the examples of the present invention and do not cover all the examples. Based on the examples of the present invention, other examples that can be obtained by those skilled in the art without any creative efforts also fall within the scope of protection of the present invention.

[0035] In the following examples, all fuel gases used are natural gases, and all oxidizing gases are oxygen.

[0036] [Example 1] D 50 700g of raw Si powder with a diameter of 5μm and D 50 300 g of raw SiO2 powder with a particle size of 0.1 μm was homogenized and compounded in an air flow mixer for 3 hours to obtain a mixed raw Si-SiO2 material. The mixed raw material was then introduced into a high-temperature vessel in the presence of fuel gas and oxygen to react (the feed rate of the mixed raw material was 60 g / min, and the initial introduction rate of the fuel gas was 50 m / s). 3 / h, and the introduction speed of the combustion-supporting gas is 150m 3 / h), and after 2 hours, the fuel gas introduction rate was increased to 2m 3 / h, and the introduction speed of the combustion-supporting gas is reduced to 15m 3 The reaction product was cooled and separated into submicron spherical silica fillers (D 50 0.7 μm) and nano-spherical silica filler (D 50 The obtained diameter was 80 nm.

[0037] [Example 2] D 50 950g of raw Si powder with a diameter of 300μm and D 50 50 g of raw SiO2 powder with a particle size of 10 μm was homogenized and compounded for 3 hours using an air flow mixer to obtain a mixed raw Si-SiO2 material. The mixed raw material was then introduced into a high-temperature vessel in the presence of fuel gas and oxygen to react (the feed rate of the mixed raw material was 60 g / min, and the initial introduction rate of the fuel gas was 50 m / s). 3 / h, and the introduction speed of the combustion-supporting gas is 150m 3 / h), and after 2 hours, the fuel gas introduction rate was increased to 2m 3 / h, and the introduction speed of the combustion gas is 15m 3 The reaction product was cooled and separated into submicron spherical silica fillers (D 50 0.4 μm) and nano-spherical silica filler (D 50 The obtained thickness was 60 nm.

[0038] [Example 3] D 50 800g of raw Al powder with a diameter of 15μm and D 50200 g of raw Al2O3 powder with a particle size of 30 nm was homogenized and compounded in a V-type mixer for 3 hours (under inert gas protection) to obtain a mixed raw Al-Al2O3 material. The mixed raw material was then introduced into a high-temperature vessel in the presence of fuel gas and oxygen to react (the feed rate of the mixed raw material was 60 g / min, and the initial introduction rate of the fuel gas was 50 m). 3 / h, and the introduction speed of the combustion-supporting gas is 150m 3 / h), and after 2 hours, the fuel gas introduction rate was increased to 2m 3 / h, and the introduction speed of the combustion-supporting gas is reduced to 15m 3 The reaction product was cooled and separated into submicron spherical aluminum oxide fillers (D 50 0.2 μm) and nano-spherical aluminum oxide fillers (D 50 The result was 50 nm.

[0039] [Example 4] D 50 700g of raw Al powder with a diameter of 15μm and D 50 300 g of raw Al2O3 powder with a diameter of 40 nm was introduced into a high-temperature vessel in the presence of fuel gas and oxygen, respectively, and reacted (the supply rate of Al powder was 42 g / min, the supply rate of Al2O3 powder was 18 g / min, and the initial introduction rate of fuel gas was 50 m 3 / h, and the introduction speed of the combustion-supporting gas is 150m 3 / h), and after 2 hours, the fuel gas introduction rate was increased to 2m 3 / h, and the introduction speed of the combustion-supporting gas is reduced to 15m 3 The reaction product was cooled and separated into submicron spherical aluminum oxide fillers (D 50 0.4 μm) and nano-spherical aluminum oxide fillers (D 50 The obtained thickness was 20 nm.

[0040] [Comparative Example 1] (Raw material M omitted) D 50 1000 g of raw material Si powder with a diameter of 12 μm was introduced into a high-temperature vessel in the presence of fuel gas and oxygen-rich oxygen and reacted (the supply rate of Si powder was 60 g / min, and the initial introduction rate of fuel gas was 50 m3 / h, and the introduction speed of the combustion-supporting gas is 150m 3 / h), and after 2 hours, the fuel gas introduction rate was increased to 2m 3 / h, and the D of the obtained spherical silica filler 50 was 0.8 μm.

[0041] [Comparative Example 2] (Increased proportion of raw material O) D 50 500g of raw Si powder with a diameter of 35μm and D 50 500 g of raw SiO2 powder with a particle size of 3.0 μm was homogenized and compounded at high speed (3 hours) using an airflow mixer to obtain a mixed raw Si-SiO2 material. The mixed raw material was then introduced into a high-temperature vessel in the presence of fuel gas and oxygen to react (the feed rate of the mixed raw material was 60 g / min, and the initial introduction rate of the fuel gas was 50 m / s). 3 / h, and the introduction speed of the combustion-supporting gas is 150m 3 / h), and after 2 hours, the fuel gas introduction rate was increased to 2m 3 / h, and the introduction speed of the combustion-supporting gas is reduced to 15m 3 The reaction product was cooled and separated into micro-spheres of silica filler (D 50 2.7 μm) and nano-spherical silica filler (D 50 The obtained diameter was 80 nm.

[0042] [Comparative Example 3] (Omitting the operation of reducing the fuel gas introduction rate) D 50 700g of raw Si powder with a diameter of 5μm and D 50 300 g of raw SiO2 powder with a particle size of 0.1 μm was subjected to high-speed homogenization and compounding (3 hours) using an air flow mixer to obtain a mixed raw Si-SiO2 material. The mixed raw material was then introduced into a high-temperature vessel in an oxygen-enriched state with fuel gas, and the feed rate of the mixed raw material was 60 g / min, and the introduction rate of the fuel gas was always 50 m / s. 3 / h, and the introduction speed of the combustion-supporting gas is always 150m 3 The reaction product was cooled and separated into submicron spherical silica fillers (D 50 0.8 μm) and nano-spherical silica filler (D 50The obtained wavelength was 82 nm.

[0043] [Comparative Example 4] (Increase in particle size of raw material M) D 50 700g of raw Si powder with a diameter of 350μm and D 50 300 g of raw SiO2 powder with a particle size of 6 μm was homogenized and coated in an airflow mixer at high speed for 3 hours to obtain a mixed raw Si-SiO2 material. The mixed raw material was then introduced into a high-temperature vessel in the presence of fuel gas and oxygen to react (the feed rate of the mixed raw material was 60 g / min, and the initial introduction rate of the fuel gas was 50 m / s). 3 / h, and the introduction speed of the combustion-supporting gas is 150m 3 / h), and after 2 hours, the fuel gas introduction rate was increased to 2m 3 / h, and the introduction speed of the combustion-supporting gas is reduced to 15m 3 The reaction mixture was cooled and then separated into a gray product and spherical silica fillers (D 50 The obtained thickness was 60 nm.

[0044] [Performance test] In the present invention, the reactivity of the raw materials is reduced by subjecting raw materials M and O to combined processing, and the reactivity of the raw materials is evaluated using the explosion pressure ratio PR (the smaller the value, the lower the risk). Note that, because raw material M reacts with oxygen and releases a large amount of heat, the present invention reduces costs by reducing the amount of fuel gas used, and makes it possible to control the temperature balance inside the container and allow the reaction to proceed more gently. Furthermore, the temperature change on the inner wall of the container during the reaction process in Examples 1 to 4 and Comparative Examples 1 to 4 was monitored, and the particle size distribution of the obtained spherical oxide filler was also evaluated using a laser particle sizer. Detailed test results are shown in Table 1.

[0045] [Table 1]

[0046] Table 1 reveals the following: (1) In Comparative Example 1, a single Si powder was used as the raw material, resulting in a high PR value of the raw material, a violent reaction, and a high production safety risk. Meanwhile, the resulting product was submicron-scale, making it difficult to obtain nanometer-scale products. (2) In Comparative Example 2, the proportion of raw material O was increased to 50%, resulting in insufficient gasification or dispersion of raw material O, resulting in coarse micron-scale particle sizes in Product 1, making it difficult to obtain submicron-scale products. (3) In Comparative Example 3, the fuel gas was not minimized, resulting in a 15% to 25% increase in product cost and a 15% to 30% increase in the temperature of the vessel inner wall, resulting in high product cost and hindering continuous production. (4) In Comparative Example 4, the particle size of the raw material Si powder reached 350 μm, and the reaction was incomplete in the high-temperature region, resulting in contamination of the product and graying the product.

[0047] Furthermore, when the appearances of the submicron-scale products and nano-scale products obtained in Examples 1 to 4 were observed, it was revealed that all of them were uniformly spherical.

[0048] The above is only a preferred embodiment of the present invention, and those skilled in the art may make some improvements and modifications without departing from the principles of the present invention, and these improvements and modifications should also be considered as within the protection scope of the present invention.

Claims

1. 1. A method for simultaneously producing nano-spherical oxide fillers and sub-micron-spherical oxide fillers, comprising: a step of subjecting a first raw material and a second raw material to a combustion reaction in the presence of a fuel gas and a combustion-supporting gas to obtain a combustion product, wherein the first raw material is a metal element powder, a non-metal element powder, or an alloy powder, the second raw material is an oxide or a composite oxide corresponding to the first raw material, the particle size of the first raw material is 3 to 300 μm, the particle size of the second raw material is 30 nm to 10 μm, and the mass of the second raw material is 30% or less of the total mass of the first raw material and the second raw material; and cooling the combustion products and then subjecting the cooled combustion products to precision separation to obtain submicron spherical oxide fillers and nano-spherical oxide fillers.

2. 2. The method according to claim 1, wherein when the combustion reaction is carried out, the first raw material and the second raw material are mixed and then supplied, and the mixing is dry mixing or liquid phase mixing.

3. 3. The method according to claim 2, wherein the liquid-phase mixing is performed by mixing the first raw material, the second raw material and a solvent, and then drying the mixture to obtain a mixed powder.

4. 4. The method of claim 3, wherein the solvent is one or more of water, methanol, ethanol, acetone, and butanone, the drying temperature is 100°C to 200°C, and the drying time is 2 hours to 30 hours.

5. 4. The method according to claim 3, wherein the equipment used for dry mixing includes a V-type mixer, a double cone mixer, a pneumatic mixer, a cone mixer, a high speed mixer or an airflow mixer.

6. 3. The method according to claim 2, wherein the first and second raw materials are mixed and then fed at a feeding rate of 1.7 g / min to 1020 g / min.

7. 3. The method of claim 2, wherein, when a first feedstock and a second feedstock are supplied during the combustion reaction, the supply rate of the first feedstock is 1.7 g / min to 700 g / min, and the supply rate of the second feedstock is 250 g / min or less.

8. 2. The method according to claim 1, wherein, in the combustion reaction, after the temperature in the reactor is stabilized, the introduction rate of the fuel gas is reduced to 2% to 10% of the initial introduction rate, and the temperature is deemed to be stable when the fluctuation of the temperature in the reactor does not exceed 10°C.

9. The initial introduction speed of the fuel gas is 50 m ３ / h, and after the temperature in the reactor stabilized, the fuel gas introduction rate was increased to 2 m ３ 9. The method according to claim 1, wherein the temperature is reduced to 1000°C / h.

10. 2. The method of claim 1, wherein the metal element powder comprises one or more of aluminum, magnesium, iron, copper, titanium, zirconium, and zinc, the non-metal element powder is silicon, and the alloy powder is one or more of aluminum-iron alloy, aluminum-silicon alloy, aluminum-magnesium alloy, magnesium alloy, and silicon-iron alloy powder.

11. 2. The method of claim 1, wherein the precision separation method includes one or more of cyclone classification, air classification, overflow classification, and sieve classification.

12. D of the submicron spherical oxide filler ５０ The particle size is 0.1 μm to 1.5 μm, and the D of the nano-spherical oxide filler ５０ 12. The method according to claim 1 or 11, wherein the particle size is between 10 nm and 100 nm.

13. 9. The method according to claim 1 or 8, wherein the fuel gas comprises one or more of hydrogen, liquefied natural gas, liquefied petroleum gas, acetylene, and propane, and the oxidizing gas comprises one or two of oxygen and air.

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