KR20200041279A - Method for surface modification of submicron silicon micropowder - Google Patents

Abstract

The present invention relates to a method for surface modification of sub-micron silicon micropowder. The method includes the steps of: introducing sub-micron silicon micropowder and deionized water at a weight ratio of 3:7-6:4 and heating them under agitation, mixing them homogeneously, transferring them to a grinder to perform preliminary dispersion homogeneously, and forming sub-micron slurry; adding a modifying agent to the sub-micron slurry and carrying out preliminary modification through wet grinding modification; transferring the preliminarily modified sub-micron slurry to a flash dryer to perform dry modification, drying the slurry to a water content of less than or equal to 0.3% at an air introduction temperature of 120-300°C and transferring the slurry to a collector to maintain constant temperature; and deagglomerating the temperature-maintained material by using an air classifier mill to a sub-micron size under a deagglomeration pressure of greater than or equal to 1.0 Mpa. The method uses deionized water as a solvent and thus does not cause waste water discharge. Therefore, the method is cost-efficient and eco-friendly, and uses a process of mechanochemical modification combined with wet modification to provide a high modification effect.

Description

METHOD FOR SURFACE MODIFICATION OF SUBMICRON SILICON MICROPOWDER

The present invention relates to the field of deep processing of inorganic non-metallic materials, and more particularly, to a method for surface modification of submicron silicon fine powder.

Silicone fine powder has advantages such as insulation, thermal stability, and chemical resistance, and is widely used in fields such as epoxy molding compound (EMC), copper-clad laminate (CCL), electrical insulation, coating agent, and adhesive. With the development of science and technology, electronic products are also developing in the direction of light and thin, and the CCL plate material is gradually becoming thinner, which requires a fine particle size for the filler used, and the general micron scale SiO2 is already used in the CCL ultra thin plate. While it cannot meet the demand for use, submicron SiO2 has better mechanical performance, processing performance, etc. in addition to meeting the demand for use; In the field of coatings and adhesives, as the awareness of eco-friendliness continues to increase, water-based coatings and adhesives are the overall development trend, and micron-scale SiO2 has a high density, so it is easily settled in the process of use, and its use is limited. In addition to meeting the requirements of sedimentation, the submicronscale SiO2 can exhibit better performance, such as better mechanical performance, better transparency, smaller fog shadows, and better feel.

Submicron silicon micropowder has a larger specific surface area than micron silicon micropowder, and since the system used directly has problems such as large viscosity and difficulty in dispersing, surface modification is required.

The surface modification of silicon fine powder produced at home and abroad can be divided into dry modification and wet modification. Dry modification is a simple process, and the production cost of the product is low, but it is difficult for the modifier to be uniformly dispersed on the surface of the silicon fine powder. The effect is not good. Dry modification is suitable only for the surface modification of micron silicon micropowder. For example, in patent CN101591478, ultrafine silicon micropowder with D50 = 3-50㎛ is selected as a raw material, and the surface is modified through dry modification using a surface modification mixture. A silicon fine powder is obtained. In the patent CN103613956A, aluminum oxide balls are put in a ball mill, and 4 ~ 16 mesh silica and a modifier hexamethyl disilazane are put in a ball mill to perform mechanical and chemical modification and sieving to modify the silicon fine particles with different particle sizes. The powder is obtained by screening.

In the case of submicron and nano-silicon fine powders, wet reforming is required. Since the problem of coagulation after drying exists in the wet modification of the submicron and nano-silicon micropowder, the monodispersity of the particles cannot be achieved, and by affecting the use effect of the product, the submicron and nano-products must have the effect. Will not be able to pay.

For example, in patent CN 103627215A, micron silicon fine powder is obtained by dry polishing using crystalline silica or molten quartz as a raw material, and then wet grinding of the micron silicon fine powder and adding a modifier to give a particle size of submicron scale. Polished to obtain a submicron silicon fine powder filter cake through compression filtration, and ultrasonic dispersion should be performed when used. This process is inconvenient to use because it requires ultrasonic dispersion when using the product.

In the patent CN10694729A3, nano-silica dispersion was prepared by using nano-silica, dispersant, and ethanol, and then the nano-silica dispersion was added to an ultrasonic generator to add and modify the composite modifier to obtain a modified nano-silica solution, and finally the modified nano-silica The solution is filtered, dried, ground, and sieved to obtain modified nanosilica. The process is complicated, and by using ethanol as a solvent, the cost is high, there is a safety risk, and at the same time, pulverization and sieve alone do not achieve monodispersion of particles.

In patent CN103194097A, 1 part by weight of silaca is added to 50 parts by weight of distilled water, stirred as a suspension, put into ultrasonic waves, and subjected to ultrasonic dispersion at 40 to 70 ° C for 10 to 30 minutes to obtain a dispersion of silaca; Subsequently, a constant amount of modifiers having different chain lengths are added to the dispersion, a drop of a crude agent is added, stirred under constant temperature and ultrasound, and then the slurry is filtered, washed, and dried to obtain a modified silica product. The process is complex, the prepared dispersion has a low solids content, a high cost, and after drying, the product has a cohesive problem, so it cannot achieve monodispersion.

In patent CN106745006A, the nanosilica product prepared by the stober method is alcohol washed, washed with water, and then freeze-dried to obtain monodisperse nanosilica powder A; System B was obtained by performing ultrasonic dispersion by adding monodisperse nanosilica powder A in ethanol; Subsequently, the system B is sealed in a reaction pot to maintain time under constant temperature and pressure conditions, and the next pressure is slowly released to atmospheric pressure to obtain hydrophobically modified nanosilica particles. The reforming method uses less freeze-drying, although it has little aggregation and obtains a monodisperse product, and the cost is relatively high.

The technical problem to be solved by the present invention is, with respect to the shortcomings of the prior art, the process is simple, economical and environmentally friendly, low cost, excellent particle dispersibility, and convenient surface modification of submicron silicon fine powder. Is to provide a way.

The technical problem to be solved by the present invention can be realized by the following technical solutions, and the surface modification method of the submicron silicon micropowder according to the present invention,

Submicron silicon fine powder and deionized water are heated in a stirring container at a mass ratio of 3: 7-6: 4 while stirring, the raw material temperature is controlled at 50-90 ° C, uniformly mixed, and then transferred to a grinding machine for preliminary dispersion. Pre-dispersion step (1) obtained by preparing a submicron slurry after uniformly dispersing by controlling the pre-dispersion temperature to 50-90 ° C .;

A modifier is added to the submicron slurry according to step (1), but the amount of modifier added is 1.0-4.0% of the submicron silicone fine powder weight, and through wet polishing reforming, the initial modification is completed, and the modifier is a silane coupling agent. , An initial modification step (2) in which hexamethyl disilazane or a mixture of silane coupling agent and hexamethyl disilazane is preferably a silane coupling agent;

The sub-micron slurry prepared in step (2) is transferred to a flash dryer to dry reform, and dried so that the moisture is ≤ 0.3% under an air inlet temperature of 120-300 ° C., and then transferred to a collector to keep warm, but the warming temperature is A secondary reforming step (3) of completing the secondary reforming by keeping the insulation under 60-120 ° C. for 20-60 min;

A deagglomeration step (4) of deagglomerating the insulated raw material with an air grinder, and deagglomerating to match the particle size before pretreatment under conditions in which the deagglomeration pressure is ≥ 1.0 MPa; It characterized in that it comprises a.

The technical problem to be solved by the present invention may be implemented in the following technical solutions, the lining of the grinding machine in step (1) is polyurethane, silicon carbide or zirconium oxide, and the grinding medium is zirconium oxide or silicon nitride, and the grinding media diameter Is 0.2-0.8 mm.

The technical problem to be solved by the present invention may be implemented in the following technical solutions, and the tungsten carbide or zirconium oxide is spray-coated on the blade and the inner wall of the flash dryer during step (3).

The technical problem to be solved by the present invention may be implemented by the following technical solutions, and the lining and classifying wheel of the air pulverizer in step (4) are aluminum oxide, zirconium oxide, or aluminum oxide on the surface of the lining and classifying wheel. Alternatively, zirconium oxide is spray coated.

The technical problem to be solved by the present invention may be implemented in the following technical solutions, and the steps are as follows.

Submicron silicon fine powder having a particle size of D50 = 0.2-1.0 μm, D100 ≤ 3.0 μm and deionized water were heated in a stirring container at a mass ratio of 3: 7-6: 4 while stirring, and the raw material temperature was adjusted to 50-90 ° C. Pre-dispersed by controlling, stirring for 3-5 min, then transferring to a grinder to pre-disperse, maintaining the raw material temperature at 50-90 ° C., pre-dispersing for 5-10 min, and preparing a submicron slurry ( One);

An initial modifier is added by adding a modifier to the submicron slurry according to step (1), wherein the amount of modifier added is 1.0-4.0% of the submicron silicone fine powder weight, and by grinding for 20-30 minutes through wet polishing reforming. Reforming step (2);

The submicron slurry prepared in step (2) is dried and reformed with a flash dryer, dried to an air inlet temperature of 120-300 ° C. so that the moisture is ≤ 0.3%, and then transferred to a collector to keep warm, but the warming temperature is 60. A secondary reforming step (3) of completing the secondary reforming by keeping the insulation under -120 ° C. for 20-60 min;

It comprises a deagglomeration step (4) to deagglomerate the insulated raw material with an air grinder, and deagglomerate such that the particle size becomes D50 = 0.2-1.0㎛, D100≤3.0㎛ under the condition that the deagglomeration pressure is ≥ 1.0MPa.

The technical problem to be solved by the present invention may be implemented in the following technical solutions, and the steps are as follows.

Submicron silicon fine powder having a particle size of D50 = 0.5-0.7㎛, D100≤3.0㎛ and deionized water were heated in a stirring container at a mass ratio of 1: 1, stirring while heating, and controlling the raw material temperature to 70 ℃, stirring time 4min After stirring for a while, pre-dispersed by transferring to a grinder, pre-dispersed for 8 min by maintaining the raw material temperature at 70 ° C., followed by a pretreatment step (1) of preparing a submicron slurry;

An initial reforming step of adding an modifier to the submicron slurry according to step (1), wherein the amount of modifier added is 2.5% of the weight of the submicron silicon micropowder, and through wet polishing reform, polishing for 25 min to complete the initial reforming ( 2);

The submicron slurry prepared in step (2) is dried and reformed with a flash dryer, dried to a moisture content of ≤ 0.3% under an air inlet temperature of 210-220 ° C., and then transferred to a collector to keep warm, but the warming temperature is 90. A secondary reforming step (3) of completing the secondary reforming by keeping the insulation under -100 ° C for 40 min;

It includes a deagglomeration step (4) to deagglomerate the insulated raw material with an air grinder, and deagglomerate such that the particle size is D50 = 0.5-0.7㎛, D100≤3.0㎛ under the condition that the deagglomeration pressure is 1.2MPa.

Compared with the prior art, the present invention uses deionized water as a solvent, so there is no wastewater discharge, and it is economical and environmentally friendly. By using a method combining mechanical and wet reforming, the reforming effect is good, By solving the problem of the agglomeration of the particles of the submicron silicon micropowder product by using air flow condensation, the particles of the submicron silicon micropowder product are sufficiently dispersed, and the product is simple to process, convenient to use, and CCL , Coatings, adhesives, etc.

The specific technical method of the present invention is further described to further understand the present invention by those skilled in the art, but does not limit the rights.

Example 1, the surface modification method of the submicron silicon micropowder,

Submicron silicon fine powder and deionized water are heated in a stirring container at a mass ratio of 3: 7-6: 4 while stirring, the raw material temperature is controlled at 50-90 ° C, uniformly mixed, and then transferred to a grinding machine for preliminary dispersion. Pre-treatment step (1) obtained by preparing a submicron slurry after uniformly dispersing;

A modifier is added to the submicron slurry according to step (1), but the amount of the modifier added is 1.0-4.0% of the submicron silicone fine powder weight, maintaining the raw material temperature at 50-90 ° C, and through wet polishing reforming, 20 An initial modification step (2) of completing the initial modification by polishing for -30 min;

The submicron slurry prepared in step (2) is transferred to a flash dryer to dry reform, and the air inlet temperature is 120-300 ° C., dried so that moisture is ≤0.3%, and then transferred to a collector to keep warm, but keep the temperature warm. A second reforming step (3) of completing the second reforming by keeping the insulation under 60-120 ° C. for 20-60 min;

A deagglomeration step (4) of deagglomerating the insulated raw material with an air grinder, and deagglomerating to match the particle size before pretreatment under conditions in which the deagglomeration pressure is ≥ 1.0 MPa; It includes.

In the method for surface modification of submicron silicon micropowder according to Example 2 and Example 1, the modifier according to step (2) is a silane coupling agent, a hexamethyl disilazane or a mixture of a silane coupling agent and hexamethyl disilazane And is preferably a silane coupling agent.

In the method for surface modification of submicron silicon micropowders according to Examples 3 and 1-2, the tungsten carbide or zirconium oxide is spray-coated on the blade and the inner wall of the flash dryer during step (3).

In the method for surface modification of submicron silicon micropowders according to Examples 4 and 1-3, the lining of the grinding machine in step (1) is polyurethane, silicon carbide or zirconium oxide, and the grinding medium is zirconium oxide or silicon nitride And the grinding media diameter is 0.2-0.8 mm.

In the surface modification method of the submicron silicon micropowder according to Example 5 or Example 1-4, the lining and classifying wheel of the air pulverizer in step (4) are aluminum oxide, zirconium oxide, or aluminum oxide on the surface. Alternatively, zirconium oxide is spray coated.

Example 6, the surface modification method of the submicron silicon micropowder,

Submicron silicon fine powder having a particle size of D50 = 0.4-0.6 μm and D100 ≤ 2.0 μm and deionized water were heated in a stirring vessel of 100 L at a mass ratio of 1: 1 and heated while stirring, and the raw material temperature was controlled to 70 ° C. and stirred. After uniformly stirring at a stirring frequency of 30 HZ for 4 min, the pre-dispersed by transferring to a 6L grinding machine and pre-dispersing the equipment rotation speed at 700-1000 RPM for 8 min, producing a submicron slurry (1);

The modifier is added to the submicron slurry according to step (1), but the amount of modifier added is 2.5% of the weight of the silicon fine powder, the raw material temperature is maintained at 70 ° C, and through wet polishing reforming, the equipment rotation speed is 800-1100RPM. An initial reforming step (2) of completing the initial reforming by grinding for 25 minutes;

The submicron slurry prepared in step (2) is dry-modified with a flash dryer, spray coated with tungsten carbide or zirconium oxide on the blades and the inner wall of the flash dryer, and the air inlet temperature is 210-220 ° C, and the moisture is ≤ 0.3%. After drying as much as possible, by transferring to a collector to keep warm, the second reforming step (3) to complete the second reforming by keeping the warming temperature at 90-100 ° C. for 40 min.

The heat-insulated material is agglomerated by an air grinder, but the lining of the air grinder and the material of the classification wheel are aluminum oxide, zirconium oxide, or the surface is spray-coated with aluminum oxide or zirconium oxide, the deagglomeration pressure is 1.2 MPa and the air grinder A solution agglomeration step (4) to agglomerate to a particle size of D50 = 0.4-0.6 µm and D100 ≤ 2.0 µm under conditions of a rotor diameter of 200 mm and a rotational speed of 3200 r / min; It includes.

Example 7, the surface modification method of the submicron silicon micropowder,

Submicron silicon fine powder having a particle size of D50 = 0.2-0.4 µm and D100 ≤ 2.0 µm and deionized water were heated in a 100 L stirring vessel at a mass ratio of 4: 6, heated while stirring, and the raw material temperature was controlled to 80 ° C. and stirred. After uniformly mixing at a stirring frequency of 30HZ for 4min, the pre-dispersed by transferring to a 6L grinding machine and pre-dispersing the equipment rotation speed at 900-1000RPM for 10min, preparing a submicron slurry (1);

The silane coupling agent KH560 is added to the submicron slurry according to step (1), but the amount of the silane coupling agent KH560 is 3.0% of the weight of the silicon fine powder, the raw material temperature is maintained at 80 ° C, and through wet abrasive modification, 30min. While polishing, the initial modification step (2) to complete the initial modification by grinding the equipment rotation speed to 1000-1100RPM;

The submicron slurry prepared in step (2) is dry-modified with a flash dryer, spray-coated tungsten carbide or zirconium oxide on the blades and the inner wall of the flash dryer, and the air inlet temperature is 250-260 ° C and the moisture is ≤ 0.3%. After drying as much as possible, by transferring to a collector to keep warm, the second reforming step (3) to complete the second reforming by keeping the warming temperature at 100-110 ° C. for 40 min.

The heat-insulated material is coagulated by an air grinder, but the lining of the air grinder and the material of the classification wheel are aluminum oxide, zirconium oxide, or, on the surface, aluminum oxide or zirconium oxide is spray coated, and the coagulation pressure is 1.6 MPa and air flow A solution agglomeration step (4) in which the particle size of the rotor is 200 mm and the rotation speed is 3500 r / min, so that the particle size is D50 = 0.2-0.4 μm and D100 ≤ 2.0 μm; It includes.

Example 8, the surface modification method of the submicron silicon fine powder,

Submicron silicon fine powder having a particle size of D50 = 0.5-0.7µm and D100≤3.0µm and deionized water are heated in a 100L stirring vessel at a mass ratio of 1: 1 and heated while stirring, and the raw material temperature is controlled to 70 ° C and stirred. After mixing uniformly at a stirring frequency of 30 HZ for 4 min, it is transferred to a 6L grinder to be polished and pre-dispersed, but the equipment rotation speed is dispersed at 800-900 RPM for 8 min to prepare a submicron slurry (1). ;

The silane coupling agent KH570 is added to the submicron slurry according to step (1), but the amount of the silane coupling agent KH570 added is 2.5% of the weight of the silicon fine powder, and the raw material temperature is maintained at 70 ° C. An initial reforming step (2) of completing the initial reforming by grinding the rotational speed at 900-1000 RPM for 25 min;

The submicron slurry prepared in step (2) is dry-modified with a flash dryer, tungsten carbide or zirconium oxide is spray-coated on the blades and the inner wall of the flash dryer, and the air inlet temperature is 260-270 ℃, and the moisture is ≤ 0.3%. After drying as possible, and then transferred to the collector to keep warm, the second reforming step (3) to complete the secondary reforming by keeping the insulation temperature at 100-110 ° C. for 40 min.

The insulated material is coagulated by an air grinder, but the lining of the air grinder and the material of the classification wheel are aluminum oxide, zirconium oxide, or aluminum oxide or zirconium oxide is spray-coated on the surface, the deagglomeration pressure is 1.2 MPa and air flow A solution agglomeration step (4) to agglomerate to a particle size of D50 = 0.5-0.7 µm and D100 ≤ 3.0 µm under the condition that the rotor diameter of the grinder is 200 mm and the rotational speed is 3200 r / min; It includes.

Example 9, the surface modification method of the submicron silicon micropowder,

Submicron silicon fine powder having a particle size of D50 = 0.4-0.6 μm and D100 ≤ 2.0 μm and deionized water were heated in a stirring vessel of 100 L at a mass ratio of 1: 1 and heated while stirring, and the raw material temperature was controlled to 70 ° C. and stirred. After mixing uniformly at a stirring frequency of 30HZ for 4min, it is transferred to a 6L grinder and polished and pre-dispersed, but after the equipment rotation speed is dispersed at 800-900RPM for 8min, a pre-treatment step obtained by preparing a submicron slurry (1 );

A mixture of silane coupling agent KH570 and hexamethyl disilazane is added to the submicron slurry according to step (1), wherein the mass ratio of KH570 and hexamethyl disilazane is 1: 1, and the silane coupling agent KH570 and hexamethyl disilala The addition amount of the mixture of the cup is 1.5% of the weight of the silicon fine powder, and the initial reforming step of completing the initial reforming by maintaining the raw material temperature at 70 ° C and grinding the equipment rotating speed at 900-1000RPM for 20min through wet polishing reforming. (2);

The submicron slurry prepared in step (2) is dry-modified with a flash dryer, and tungsten carbide or zirconium oxide is spray-coated on the blades and the inner wall of the flash dryer, and the air inlet temperature is 230-240 ° C, and the moisture is ≤ 0.3%. After drying as possible, and then transferred to the collector to keep warm, the second reforming step (3) to complete the secondary reforming by keeping the insulation temperature at 90-100 ° C. for 40 min.

The insulated material is coagulated by an air grinder, but the lining of the air grinder and the material of the classification wheel are aluminum oxide, zirconium oxide, or aluminum oxide or zirconium oxide is spray-coated on the surface, the deagglomeration pressure is 1.2 MPa and air flow A solution agglomeration step (4) in which the particle diameter of the rotor is 200 mm and the rotation speed is 3200 r / min, so that the particle size is D50 = 0.4-0.6 μm and D100 ≤ 2.0 μm; It includes.

Example 10, the surface modification method of the submicron silicon micropowder,

The silicon fine powder having a particle size of D50 = 0.6-0.8 µm and D100 ≤ 3.0 µm and deionized water were heated in a 100 L stirring vessel at a mass ratio of 6: 4, heated while stirring, and the raw material temperature was controlled at 50 ° C., stirring time 4 min. Pre-dispersed by uniformly mixing at a stirring frequency of 30HZ and then transferring to a 6L grinding machine to disperse the equipment rotational speed at 700-800RPM for 8min, and then preparing a submicron slurry (1);

Hexamethyl disilazane is added to the submicron slurry according to step (1), but the amount of hexamethyl disilazane added is 1.0% of the weight of the silicon fine powder, and the raw material temperature is maintained at 50 ° C, through wet polishing reforming. , Initial modification step (2) to complete the initial modification by grinding the equipment rotation speed at 800-900RPM for 20min;

The submicron slurry prepared in step (2) is dry-modified with a flash dryer, tungsten carbide or zirconium oxide is spray-coated on the blades and the inner wall of the flash dryer, and the air inlet temperature is under 130-140 ° C, and the moisture is ≤ 0.3%. After drying as possible, and then transferred to the collector to keep warm, the second reforming step (3) to complete the second reforming by keeping the warming temperature at 60-70 ° C. for 20 min.

The heat-insulated material is agglomerated by an air grinder, but the lining of the air grinder and the material of the classification wheel are aluminum oxide, zirconium oxide, or aluminum oxide or zirconium oxide is spray-coated on the surface, the deagglomeration pressure is 1.0 MPa, and the air flow A solution agglomeration step (4) to agglomerate to a particle size of D50 = 0.6-0.8 µm and D100 ≤ 3.0 µm under the condition that the rotor diameter of the grinder is 200 mm and the rotational speed is 3100 r / min; It includes.

When the submicron silicone micropowder product after modification prepared in Example 8 is compared with the unmodified submicron silicone micropowder product, the product performance is as shown in the following table.

Item
designation Granularity
Activation rate,% Oil absorption value, g / 100g
Sedimentation D50, μm D100, μm Unmodified silicone fine powder
0.52
1.82
0
58.2
8 Modified silicone fine powder
0.55
1.91
100
44.6
20

As can be seen from the above table,

1) The submicron silicon fine powder product does not basically change the particle size before and after modification (D50, D100). This product is not agglomerated and has excellent dispersibility. Means to prevent the problem of product agglomeration afterwards;

2) The activation rate of the submicron silicon micropowder product after modification reaches 100%, which means that each one particle is basically coated with a modifier, so that the modification effect is relatively good;

3) The submicron silicone fine powder product after modification has a significantly lower oil absorption value, which means that the modification effect is good, the viscosity is low in the application process, the fluidity is good, and the dispersibility is good;

4) The submicron silicon fine powder product after modification significantly increases the sedimentation time, which means that the modification effect is good, the sedimentation prevention effect is good when applied, and the storage cycle is long.

The present invention obtains a surface treatment submicron silicon fine powder having a good modification effect by using a submicron silicon fine powder through pre-treatment, initial modification, secondary modification, and deagglomeration, which is simple, economical, and eco-friendly. , Cost is low, product modification effect is good, particles are well dispersed, convenient to use, and can be widely used in fields such as CCL, coating agent, adhesive.

Claims (8)

Submicron silicon fine powder and deionized water are heated in a stirring container at a mass ratio of 3: 7-6: 4 while stirring, the raw material temperature is controlled at 50-90 ° C, uniformly mixed, and then transferred to a grinding machine for preliminary dispersion. Pre-dispersion step (1) obtained by preparing a submicron slurry after uniformly dispersing by controlling the pre-dispersion temperature to 50-90 ° C .;
A modifier is added to the submicron slurry according to step (1), but the amount of the modifier added is 1.0-4.0% of the weight of the submicron silicone fine powder, and through wet polishing reforming, the initial modification is completed, and the modifier is a silane coupling agent. , An initial modification step (2) which is a hexamethyl disilazane or a mixture of silane coupling agent and hexamethyl disilazane;
The sub-micron slurry prepared in step (2) is transferred to a flash dryer to dry reform, and dried under air inlet temperature of 120-300 ° C. so that moisture is ≤ 0.3%, and then transferred to a collector to keep warm, but to keep warm. A secondary reforming step (3) of completing the secondary reforming by keeping the insulation under 60-120 ° C. for 20-60 min;
A deagglomeration step (4) of deagglomerating the insulated raw material with an air flow grinder, under the condition that the deagglomeration pressure is ≥ 1.0 MPa, to match the particle size before pretreatment; Method for surface modification of submicron silicon micropowder, characterized in that it comprises a. According to claim 1,
The modifier according to step (2) is a surface modification method of a submicron silicon micropowder, characterized in that the silane coupling agent. The method of claim 1 or 2,
The surface modification of the submicron silicon fine powder, characterized in that the lining of the grinding machine in step (1) is polyurethane, silicon carbide or zirconium oxide, the grinding medium is zirconium oxide or silicon nitride, and the grinding medium diameter is 0.2-0.8 mm. Way. The method of claim 1 or 2,
A method of surface modification of submicron silicon micropowder, characterized in that tungsten carbide or zirconium oxide is spray coated on the blade and inner wall of the flash dryer during step (3), and the air inlet temperature is 120-300 ° C. The method of claim 1 or 2,
In the step (4), the lining and classifying wheel of the air pulverizer are aluminum oxide, zirconium oxide, or aluminum lining or zirconium oxide is spray-coated on the surface of the lining and classifying wheel, and the agglomeration pressure is ≥1.0 MPa. Submicron silicon micropowder surface modification method. The method of claim 1 or 2,
The particle size of the submicron silicon micropowder of step (1) is D50 = 0.2-1.0㎛, D100≤3.0㎛ surface modification method of the submicron silicon micropowder, characterized in that. According to claim 1,
Submicron silicon fine powder having a particle size of D50 = 0.2-1.0 μm, D100 ≤ 3.0 μm and deionized water were heated in a stirring container at a mass ratio of 3: 7-6: 4 while stirring, and the raw material temperature was adjusted to 50-90 ° C. Pre-dispersed by controlling, stirring for 3-5 min, then transferring to a grinder to pre-disperse, maintaining the raw material temperature at 50-90 ° C. for pre-dispersing for 5-10 min, and then preparing a submicron slurry ( One);
An initial modifier is added by adding a modifier to the submicron slurry according to step (1), wherein the amount of modifier added is 1.0-4.0% of the submicron silicone fine powder weight, and by grinding for 20-30 minutes through wet polishing reforming. Reforming step (2);
The submicron slurry prepared in step (2) is dried and reformed with a flash dryer, dried to a moisture content of ≤0.3% under an air inlet temperature of 120-300 ° C., and then transferred to a collector to keep warm, but the warming temperature is 60. A secondary reforming step (3) of completing the secondary reforming by keeping the insulation under -120 ° C. for 20-60 min;
A deagglomeration step (4) of deagglomerating the insulated raw material with an air grinder, and deagglomerating such that the particle size is D50 = 0.2-1.0 mu m, D100≤3.0 mu m under conditions that the deagglomeration pressure is ≥1.0 MPa; Method for surface modification of submicron silicon micropowder, characterized in that it comprises a. The method of claim 7,
Submicron silicon fine powder having a particle size of D50 = 0.5-0.7㎛, D100≤3.0㎛ and deionized water were heated in a stirring container at a mass ratio of 1: 1, stirring while heating, and controlling the raw material temperature to 70 ℃, stirring time 4min After stirring for a while, pre-dispersed by transferring to a grinder, pre-dispersing for 8 min by maintaining the raw material temperature at 70 ° C., thereby preparing a submicron slurry (1);
An initial reforming step (2) in which the modifier is added to the submicron slurry according to step (1), but the amount of the modifier added is 2.5% of the weight of the submicron silicon micropowder, and through wet polishing reform, grinding for 25 minutes to complete the initial reforming. ;
The submicron slurry prepared in step (2) is dried and reformed with a flash dryer, dried under an air inlet temperature of 210-220 ° C., so that moisture is ≤ 0.3%, and then transferred to a collector to keep warm, but the warming temperature is 90. A secondary reforming step (3) of completing the secondary reforming by keeping the insulation under -100 ° C for 40 min;
A deagglomeration step (4) of deagglomerating the insulated raw material with an air grinder, and deagglomerating such that the particle size is D50 = 0.5-0.7µm, D100≤3.0µm, under the condition that the deagglomeration pressure is 1.2MPa; Method for surface modification of submicron silicon micropowder, characterized in that it comprises a.