Preparation method of crystalline silicon micro-powder with high activation degree
By alkali modification and silane coupling agent modification on crystalline silicon micropowder, the problem of low activation of crystalline silicon micropowder is solved, its compatibility with downstream products is improved, and its application in high-end fields is expanded.
Patent Information
- Application Number
- CN202510650214.1
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2025-05-20
- Publication Date
- 2025-07-11
AI Technical Summary
The low activation degree of crystalline silicon micropowder leads to poor compatibility with the substrates of downstream products, limiting its application in high-end fields.
Using post-synthetic modification technology, the surface modification is performed by mixing the crystalline silicon micropowder with an alkaline solution, and then mixing it with silane coupling agent and anhydrous ethanol to increase the number of hydroxyl groups on the surface of the crystalline silicon micropowder and improve the activation degree.
The activation degree of crystalline silicon micropowder is significantly improved, its compatibility and dispersion with silane coupling agents and polymer substrates are improved, and it meets the needs of high-end copper clad plates and chip packaging.
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Figure CN120288774A_ABST
Abstract
Description
Technical Field
[0001] The present invention relates to the technical field of silica powder, and particularly to a preparation method of highly activated crystalline silica powder. Background Art
[0002] Silica powder has stable physical and chemical properties and exhibits good performance in multiple fields, such as electronic packaging, electrical industry, epoxy molding compounds, plastics and rubbers, special ceramics, optical glass, coatings, and adhesives. Currently, the widely used silica powders mainly include spherical silica powder, fused silica powder, and crystalline silica powder. Spherical silica powder has good compatibility with the substrates of downstream products due to its unique morphological structure and is widely used in high-end fields such as copper clad laminates and electronic packaging. However, its complicated preparation process makes its cost remain high, severely restricting the application of spherical silica powder. Crystalline silica powder is a powder material processed from high-grade natural quartz ore through processes such as cleaning, crushing, magnetic separation, ultrafine grinding, and classification. The cost of the preparation process is only one-fifth of that of spherical silica powder. However, the activation degree of crystalline silica powder is relatively low, resulting in poor compatibility with the substrates of downstream products, which greatly restricts the application of crystalline silica powder in high-end fields.
[0003] The post-synthesis modification technology is an innovative method for modifying the surface of inorganic powder materials. Based on the theory of organic methodology, this technology bonds organic modifiers to the surface of inorganic powder materials through post-synthesis chemical bonds to achieve the directional functionalization of inorganic powder materials. Compared with traditional modification methods, the post-synthesis modification technology has the advantages of high modification efficiency, low consumption of organic modifiers, low cost, and environmental friendliness. It can significantly improve the application performance of inorganic powder materials and even endow new functions, thus meeting the application requirements of high-end fields.
[0004] Therefore, the preparation of highly activated crystalline silica powder through the post-synthesis modification technology is crucial for expanding the application of crystalline silica powder. Summary of the Invention
[0005] The purpose of the present invention is to provide a preparation method of highly activated crystalline silica powder in view of the deficiencies of the prior art.
[0006] In order to achieve the above-mentioned invention purpose, the present invention provides the following technical solutions:
[0007] The present invention provides a preparation method of highly activated crystalline silica powder, comprising the following steps:
[0008] 1) Mix crystalline silica powder and an alkaline solution to obtain alkali-modified crystalline silica powder;
[0009] 2) Mix the alkali-modified crystalline silica powder, a silane coupling agent, and absolute ethanol for surface modification to obtain highly activated crystalline silica powder.
[0010] Preferably, the alkaline solution described in step 1) includes one or more of sodium hydroxide solution, potassium hydroxide solution, calcium hydroxide solution, and ammonia water, and the concentration of the alkaline solution is 1-10 mol / L.
[0011] Preferably, the particle size of the crystalline silica powder described in step 1) is 2000-4000 mesh.
[0012] Preferably, the mass of the alkaline solution described in step 1) is 0.5-4 times the mass of the crystalline silica powder.
[0013] Preferably, the mixing in step 1) is carried out under the conditions of reflux stirring, the temperature of reflux stirring is 90-120 °C, the rotation speed of reflux stirring is 900-1500 rpm, and the time of reflux stirring is 1-6 h.
[0014] Preferably, the silane coupling agent described in step 2) is a silane coupling agent containing an epoxy group.
[0015] Preferably, the mass of the silane coupling agent described in step 2) is 0.1-1% of the mass of the alkali-modified crystalline silica powder, and the mass ratio of absolute ethanol to the alkali-modified crystalline silica powder is 1:10-20.
[0016] Preferably, the temperature of the surface modification in step 2) is 90-120 °C, the time of surface modification is 5-45 min, and the surface modification is carried out under stirring conditions, and the rotation speed of stirring is 900-1500 rpm.
[0017] Advantages of the present invention:
[0018] After the crystalline silica powder of the present invention is modified by alkali, the number of hydroxyl groups on the surface is significantly increased, providing more reaction sites for the subsequent modification with silane coupling agent, and significantly improving the activation degree of the crystalline silica powder, up to 90.5%; the present invention uses the post-synthesis modification technology to modify the surface of the crystalline silica powder, constructing the functional groups on the surface of the crystalline silica powder at the molecular level, improving the compatibility and dispersibility between the crystalline silica powder and the silane coupling agent, polymer substrate, etc., so that it can meet the requirements of high-end copper clad laminates, chip packaging and other fields. Description of the Drawings
[0019] Figure 1 It is the infrared spectrogram of the crystalline silica powder before and after alkali modification in Example 1. Detailed Embodiments
[0020] The present invention provides a preparation method of highly activated crystalline silica powder, which includes the following steps:
[0021] 1) Mix the crystalline silica powder and the alkaline solution to obtain alkali-modified crystalline silica powder;
[0022] 2) Mix the alkali-modified crystalline silica powder, silane coupling agent and absolute ethanol, and conduct surface modification to obtain highly activated crystalline silica powder.
[0023] In the present invention, the alkaline solution described in step 1) preferably comprises one or more of sodium hydroxide solution, potassium hydroxide solution, calcium hydroxide solution and ammonia water. The concentration of the alkaline solution is preferably 1 - 10 mol / L, more preferably 3 - 8 mol / L, and still more preferably 4 - 7 mol / L.
[0024] In the present invention, the particle size of the crystalline silica powder described in step 1) is preferably 2000 - 4000 mesh, more preferably 2500 - 3500 mesh, and still more preferably 3000 mesh.
[0025] In the present invention, the mass of the alkaline solution described in step 1) is preferably 0.5 - 4 times the mass of the crystalline silica powder, more preferably 1 - 3 times, and still more preferably 1.5 - 2 times.
[0026] In the present invention, the mixing in step 1) is preferably carried out under the conditions of reflux stirring. The temperature of reflux stirring is preferably 90 - 120 °C, more preferably 95 - 115 °C, and still more preferably 100 - 110 °C; the rotation speed of reflux stirring is preferably 900 - 1500 rpm, more preferably 1000 - 1300 rpm, and still more preferably 1100 - 1200 rpm; the time of reflux stirring is preferably 1 - 6 h, more preferably 2 - 5 h, and still more preferably 3 - 4 h.
[0027] In the present invention, the silane coupling agent described in step 2) is preferably a silane coupling agent containing an epoxy group.
[0028] In the present invention, the mass of the silane coupling agent described in step 2) is preferably 0.1 - 1% of the mass of the alkali-modified crystalline silica powder, more preferably 0.2 - 0.8%, and still more preferably 0.3 - 0.6%; the mass ratio of absolute ethanol to the alkali-modified crystalline silica powder is preferably 1:10 - 20, more preferably 1:12 - 18, and still more preferably 1:15.
[0029] In the present invention, the temperature of the surface modification described in step 2) is preferably 90 - 120 °C, more preferably 95 - 115 °C, and still more preferably 100 - 110 °C; the time of surface modification is preferably 5 - 45 min, more preferably 10 - 35 min, and still more preferably 20 - 30 min; the surface modification is preferably carried out under stirring conditions, and the rotation speed of stirring is preferably 900 - 1500 rpm, more preferably 1000 - 1300 rpm, and still more preferably 1100 - 1200 rpm.
[0030] The technical solutions provided by the present invention will be described in detail below in conjunction with the embodiments, but they should not be construed as limiting the protection scope of the present invention.
[0031] The silane coupling agent used in the examples and comparative examples of the present invention is γ-glycidoxypropyltrimethoxysilane, and the crystalline silica powder is the GS series crystalline silica powder produced by Jiangxi Guangyuan Chemical Co., Ltd.
[0032] Example 1
[0033] 1000 g of GS-3000 silica powder (the particle size of the silica powder is 3000 mesh) was mixed with 500 g of sodium hydroxide solution with a concentration of 10 mol / L, placed in a reflux stirrer, and refluxed and stirred at 1200 rpm for 1 h at 100 °C. Subsequently, it was dried at 100 °C for 1 h to obtain alkali-modified crystalline silica powder. The alkali-modified crystalline silica powder, silane coupling agent, and absolute ethanol were placed in a high-speed mixer (the mass ratio of the alkali-modified crystalline silica powder, silane coupling agent, and absolute ethanol was 100:1:10), and surface modification was carried out at 900 rpm at 90 °C for 5 min, and then naturally cooled to room temperature to obtain highly activated crystalline silica powder.
[0034] Figure 1 is the infrared spectrogram of the crystalline silica powder in Example 1 before and after alkali modification. From Figure 1 It can be seen that after alkali modification, the number of hydroxyl groups on the surface of the crystalline silica powder increases significantly. The increase in the number of hydroxyl groups provides more reaction sites for the subsequent modification of the crystalline silica powder with silane coupling agent, significantly improving the activation degree of the crystalline silica powder.
[0035] Example 2
[0036] 1000 g of GS-3500 silica powder (the particle size of the silica powder is 3500 mesh) was mixed with 4000 g of sodium hydroxide solution with a concentration of 4 mol / L, placed in a reflux stirrer, and refluxed and stirred at 1500 rpm for 4 h at 90 °C. Subsequently, it was dried at 100 °C for 1 h to obtain alkali-modified crystalline silica powder. The alkali-modified crystalline silica powder, silane coupling agent, and absolute ethanol were placed in a high-speed mixer (the mass ratio of the alkali-modified crystalline silica powder, silane coupling agent, and absolute ethanol was 100:0.3:7), and surface modification was carried out at 1500 rpm at 100 °C for 45 min, and then naturally cooled to room temperature to obtain highly activated crystalline silica powder.
[0037] Example 3
[0038] Mix 1000 g of GS-2500 silica powder (the particle size of the silica powder is 2500 mesh) with 3000 g of sodium hydroxide solution with a concentration of 1 mol / L, place it in a reflux stirrer, and reflux and stir at 110 °C at a speed of 1300 rpm for 6 h. Subsequently, dry it at 100 °C for 1 h to obtain alkali-modified crystalline silica powder. Place the alkali-modified crystalline silica powder, silane coupling agent, and absolute ethanol in a high-speed mixer (the mass ratio of the alkali-modified crystalline silica powder, silane coupling agent, and absolute ethanol is 100:1:5), carry out surface modification at 120 °C at a speed of 1000 rpm for 30 min, and then naturally cool to room temperature to obtain highly activated crystalline silica powder.
[0039] Example 4
[0040] Mix 1000 g of GS-2000 silica powder (the particle size of the silica powder is 2000 mesh) with 2000 g of sodium hydroxide solution with a concentration of 3 mol / L, place it in a reflux stirrer, and reflux and stir at 120 °C at a speed of 900 rpm for 2 h. Subsequently, dry it at 100 °C for 1 h to obtain alkali-modified crystalline silica powder. Place the alkali-modified crystalline silica powder, silane coupling agent, and absolute ethanol in a high-speed mixer (the mass ratio of the alkali-modified crystalline silica powder, silane coupling agent, and absolute ethanol is 100:0.6:10), carry out surface modification at 115 °C at a speed of 1200 rpm for 10 min, and then naturally cool to room temperature to obtain highly activated crystalline silica powder.
[0041] Example 5
[0042] Mix 1000 g of GS-4000 silica powder (the particle size of the silica powder is 4000 mesh) with 1000 g of sodium hydroxide solution with a concentration of 8 mol / L, place it in a reflux stirrer, and reflux and stir at 100 °C at a speed of 1200 rpm for 5 h. Subsequently, dry it at 100 °C for 1 h to obtain alkali-modified crystalline silica powder. Place the alkali-modified crystalline silica powder, silane coupling agent, and absolute ethanol in a high-speed mixer (the mass ratio of the alkali-modified crystalline silica powder, silane coupling agent, and absolute ethanol is 100:1:10), carry out surface modification at 110 °C at a speed of 1300 rpm for 20 min, and then naturally cool to room temperature to obtain highly activated crystalline silica powder.
[0043] Example 6
[0044] Mix 1000 g of GS-3000 silica powder (the particle size of the silica powder is 3000 mesh) with 500 g of sodium hydroxide solution with a concentration of 7 mol / L, place it in a reflux stirrer, and reflux and stir at 1200 rpm at 100 °C for 3 h. Then dry it at 100 °C for 1 h to obtain alkali-modified crystalline silica powder. Place the alkali-modified crystalline silica powder, silane coupling agent, and absolute ethanol in a high-speed mixer (the mass ratio of the alkali-modified crystalline silica powder, silane coupling agent, and absolute ethanol is 100:1:10), and carry out surface modification at 95 °C at 1100 rpm for 35 min, and then naturally cool to room temperature to obtain highly activated crystalline silica powder.
[0045] Example 7
[0046] Replace the sodium hydroxide solution in Example 5 with a potassium hydroxide solution, and the others are the same as in Example 5.
[0047] Example 8
[0048] Replace the sodium hydroxide solution in Example 5 with a calcium hydroxide solution, and the others are the same as in Example 5.
[0049] Example 9
[0050] Replace the sodium hydroxide solution in Example 5 with ammonia water, and the others are the same as in Example 5.
[0051] Comparative Example 1
[0052] Place GS-3000 silica powder, silane coupling agent, and absolute ethanol in a high-speed mixer (the mass ratio of silica powder, silane coupling agent, and absolute ethanol is 100:1:10), and carry out surface modification at 110 °C at 1300 rpm for 20 min, and then naturally cool to room temperature to obtain modified crystalline silica powder.
[0053] Comparative Example 2
[0054] Mix 1000 g of GS-4000 silica powder (the particle size of the silica powder is 4000 mesh) with 1000 g of ammonia water with a concentration of 8 mol / L, place it in a reflux stirrer, and reflux and stir at 1200 rpm at 100 °C for 5 h. Then dry it at 100 °C for 1 h to obtain modified crystalline silica powder.
[0055] Test the activation degree of the crystalline silica powder prepared in Examples 1-9 and Comparative Examples 1-2 according to HG / T 2006-2006, and the test results are shown in Table 1.
[0056] Table 1 Test results of the activation degree of crystalline silica powder
[0057] Serial number Degree of activation / % Serial number Degree of activation / % Serial number Degree of activation / % Example 1 85.2 Example 5 82.8 Example 9 90.5 Example 2 83.2 Example 6 88.3 Comparative example 1 64.1 Example 3 84.1 Example 7 84.6 Comparative example 2 57.8 Example 4 84.6 Example 8 88.7 —— ——
[0058] As can be seen from Table 1, the activation degrees of the crystalline silica powder modified with an alkali in Examples 1 to 9 and then modified with a silane coupling agent are significantly higher than those of Comparative Example 1 without alkali modification, and are also significantly higher than those of Comparative Example 2 with alkali modification but without silane coupling agent modification.
[0059] The above are only the preferred embodiments of the present invention. It should be noted that for those of ordinary skill in the art, without departing from the principle of the present invention, several improvements and refinements can be made, and these improvements and refinements should also be regarded as the protection scope of the present invention.
Claims
1. A preparation method of highly activated crystalline silica powder, characterized in that, It includes the following steps: 1) Mix crystalline silicon micropowder and an alkaline solution to obtain alkali-modified crystalline silicon micropowder; 2) Mix the alkali-modified crystalline silicon micropowder, a silane coupling agent and absolute ethanol for surface modification to obtain highly activated crystalline silicon micropowder.
2. The preparation method according to claim 1, wherein The alkaline solution described in step 1) includes one or more of sodium hydroxide solution, potassium hydroxide solution, calcium hydroxide solution and ammonia water, and the concentration of the alkaline solution is 1-10 mol / L.
3. The preparation method according to claim 1 or 2, characterized in that, The particle size of the crystalline silicon micropowder described in step 1) is 2000-4000 mesh.
4. The preparation method according to claim 3, characterized in that, The mass of the alkaline solution described in step 1) is 0.5-4 times the mass of the crystalline silicon micropowder.
5. The preparation method according to claim 4, characterized in that, The mixing in step 1) is carried out under the conditions of reflux stirring, the temperature of reflux stirring is 90-120 °C, the rotation speed of reflux stirring is 900-1500 rpm, and the time of reflux stirring is 1-6 h.
6. The preparation method according to claim 4 or 5, characterized in that, The silane coupling agent described in step 2) is a silane coupling agent containing an epoxy group.
7. The preparation method according to claim 6, characterized in that, The mass of the silane coupling agent described in step 2) is 0.1-1% of the mass of the alkali-modified crystalline silicon micropowder, and the mass ratio of absolute ethanol to the alkali-modified crystalline silicon micropowder is 1:10-20.
8. The preparation method according to claim 7, characterized in that, The temperature of the surface modification described in step 2) is 90-120 °C, the time of surface modification is 5-45 min, and the surface modification is carried out under stirring conditions, and the rotation speed of stirring is 900-1500 rpm.