CN113213495A - Preparation method of precipitated silica for high-resilience transparent silicone rubber - Google Patents
Preparation method of precipitated silica for high-resilience transparent silicone rubber Download PDFInfo
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- C01B33/00—Silicon; Compounds thereof
- C01B33/113—Silicon oxides; Hydrates thereof
- C01B33/12—Silica; Hydrates thereof, e.g. lepidoic silicic acid
- C01B33/18—Preparation of finely divided silica neither in sol nor in gel form; After-treatment thereof
- C01B33/187—Preparation of finely divided silica neither in sol nor in gel form; After-treatment thereof by acidic treatment of silicates
- C01B33/193—Preparation of finely divided silica neither in sol nor in gel form; After-treatment thereof by acidic treatment of silicates of aqueous solutions of silicates
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Abstract
The invention belongs to the technical field of silicon dioxide, and particularly relates to a preparation method of precipitated silicon dioxide for high-resilience transparent silicone rubber. The precipitated silica for high-resilience silicone rubber provided by the invention is prepared by a two-step method by using water as a reaction base solution, a sodium silicate solution and a sulfuric acid solution with the modulus of 1.5-3.5 as reaction raw materials and an organic silicon compound with the mass fraction of 0.01-0.1% as an auxiliary agent. The specific surface area of the precipitated silica for the high-resilience silicone rubber provided by the invention is 150-210m2The oil absorption value is 150-210mL/100g, the rebound resilience of the silicone rubber is 60-75 percent when the silicone rubber is applied to the silicone rubber, and the silicone rubber is transparent and has no impurities. In addition, the preparation process of the precipitated silica for the high-resilience silicone rubber provided by the invention is simple and environment-friendly, has lower production cost, and is easy to implementThe industrial production is carried out.
Description
Technical Field
The invention belongs to the technical field of silicon dioxide, and particularly relates to a preparation method of precipitated silicon dioxide for high-resilience transparent silicone rubber.
Background
The precipitated silica is mainly prepared by a coprecipitation method, belongs to an amorphous mesoporous material, and is prepared from water glass (Na) serving as a raw material2SiO3) And sulfuric acid (H)2SO4) Sodium sulfate (Na) as by-product2SO4) The method has the advantages of recycling, simple production process, environmental protection and low cost. Compared with fumed silica, the precipitated silica has low cost and more environment-friendly production process.
The precipitated silica is an amorphous porous structure, the surface of the precipitated silica is rich in hydroxyl, and the specific surface area of the precipitated silica is adjustable. The silicon dioxide is added into the silicon rubber, and because the silicon dioxide forms a three-dimensional network structure in a system and can form a crosslinking effect with rubber macromolecules, the addition of the silicon dioxide can effectively improve the reinforcing effect of the silicon rubber. At present, compared with fumed silica, the rubber prepared by adding precipitated silica has general resilience and transparency, the higher oil absorption value leads to long powder eating time of raw rubber, the higher surface hydroxyl content leads to high addition amount of a structural control agent (such as hydroxyl silicone oil), and the production cost is increased. Therefore, it is required to develop a precipitated silica which is effective in improving transparency and resilience of silicone rubber.
Patent publication No. CN110272594A discloses a high-temperature-resistant rubber and a preparation method thereof, wherein the rubber is prepared from ethylene propylene diene monomer, polyisoprene rubber, hydroxyl-terminated styrene-butadiene rubber, epichlorohydrin rubber, polyethylene wax, fumed silica, serpentine, microcrystalline cellulose, alcohol ether glycoside, dilauryl thiodipropionate, asphalt fiber, diisopropyl xanthogen disulfide, dilauryl thiodipropionate, palm wax, carbon black, dipentene and an anti-aging agent. The rubber has better rebound resilience, mechanical strength and stability, but the fumed silica adopted in the formula has higher production cost and poor environmental protection property of the production process, and is not beneficial to large-scale industrial production.
Patent publication No. CN162144A discloses a silicone rubber composition, which comprises components such as polyorganosiloxane, organosilane or a mixture thereof, precipitated silica, and a curing agent, and which has good storage stability due to little plastic degradation with time, good workability due to little adhesion to a roller, and improved rebound resilience after curing, but has poor transparency.
In summary, the technical problems of poor rebound resilience and transparency, long raw rubber powder eating time, large addition amount of the structural control agent, high production cost and the like caused by adding the precipitated silica into the silicone rubber generally exist in the prior art.
Disclosure of Invention
In order to overcome the defects of the prior art, the invention aims to provide precipitated silica for high-resilience silicone rubber and a preparation method thereof. The specific surface area of the precipitated silica for the high-resilience silicone rubber provided by the invention is 150-210m2The oil absorption value is 150-210mL/100g, the rebound resilience of the silicone rubber is 60-75 percent when the silicone rubber is applied to the silicone rubber, and the silicone rubber is transparent and has no impurities. In addition, the preparation process of the precipitated silica for the high-resilience silicone rubber provided by the invention is simple and environment-friendly, has lower production cost, and is easy to realize industrial production.
In order to achieve the purpose, the technical scheme of the invention is as follows:
a preparation method of precipitated silica for high-resilience silicone rubber comprises the following steps:
s1, liquefying solid sodium silicate at high temperature, and adding water to prepare a sodium silicate solution with the concentration of 2.0-3.0 mol/L;
s2, preparing a sulfuric acid solution with the concentration of 2.0-4.8 mol/L;
s3, adding tap water into the reaction kettle, then adding the sodium silicate solution prepared in the step S1, heating to 80-95 ℃, starting a stirring device, dropwise adding the sulfuric acid solution prepared in the step S2 under the stirring state, and controlling the pH value of the reaction end point to be 8.0-10.5;
s4, continuously adding the sodium silicate solution prepared in the step S1 and the sulfuric acid solution prepared in the step S2 dropwise into the reaction kettle at the same time under the stirring state, controlling the pH value in the reaction process to be 8.0-10.5, stopping adding the sodium silicate solution dropwise when the adding amount of the sodium silicate solution reaches a preset amount, continuously adding the sulfuric acid solution prepared in the step S2 dropwise until the pH value in the reaction system is 2.5-5.0, adding an organic silicon compound, aging for 60-120min, and performing filter pressing to obtain a filter cake;
s5, smashing the filter cake prepared in the step S4, washing, transporting the slurry to a thick slurry tank, adding a proper amount of water, uniformly stirring, adjusting the solid content of the thick slurry to 15-20%, spray drying, grinding and crushing to obtain the high-performance high-efficiency high-.
Further, the modulus of the solid sodium silicate in the step S1 of the preparation method of the precipitated silica for high resilience silicone rubber is 1.5 to 3.5.
Further, the amount of tap water added in step S3 of the preparation method of the precipitated silica for high resilience silicone rubber is 8-12m3The addition amount of sodium silicate is 5-7.5m3。
Further, the preparation method of the precipitated silica for high resilience silicone rubber has the stirring frequency of 25 to 30Hz and the dropping speed of the sulfuric acid solution of 3 to 8m in the stirring device in the step S33/h。
Further, the dropping speed of the sodium silicate solution in the step S4 of the preparation method of the precipitated silica for high resilience silicone rubber is 8-12m3The dropping speed of the sulfuric acid solution is 3-8m3/h。
Further, the preset amount of the sodium silicate solution in the step S4 of the preparation method of the precipitated silica for high resilience silicone rubber is 10-15m3。
Further, in the step S4 of the preparation method of the precipitated silica for high resilience silicone rubber, the organosilicon compound is hydroxy silicone oil, and the addition amount of the organosilicon compound is 0.01-0.1% of the total amount of the solid sodium silicate.
Further, the preparation method of the precipitated silica for high resilience silicone rubber is that the D50 particle size of the silica is controlled to be 10-16 μm when the silica is ground and crushed in step S5.
The invention also provides the precipitated silica for high-resilience silicone rubber prepared by the preparation method of the precipitated silica for high-resilience silicone rubber.
The precipitated silica for high-resilience silicone rubber provided by the invention is prepared by a two-step method by using water as a reaction base solution, a sodium silicate solution and a sulfuric acid solution with the modulus of 1.5-3.5 as reaction raw materials and an organic silicon compound with the mass fraction of 0.01-0.1% as an auxiliary agent.
The first step of the preparation method of the precipitated silica for the high-resilience silicone rubber provided by the invention is to prepare a high-concentration (2.0-3.0mol/L) sodium silicate solution, the concentration of silicic acid molecules in unit volume is high, the collision among silica particles is favorably improved during dehydration condensation, the number of exposed surface hydroxyls on the particle surface is reduced, and the content of a structural control agent in the silicone rubber is reduced. Then adding 5-7.5m of water as base solution3Then gradually dripping sulfuric acid solution, and generating silica particles with large specific surface area under the strong alkali condition.
The second step is to add sulfuric acid solution and sodium silicate solution synchronously under the conditions of pH 8.0-10.5 and temperature 80-95 deg.C, and grow on the basis of the silica particles generated in the first step, and the silica particles grow up. Under the condition of the pH value, the content of hydroxyl on the surface of the silicic acid monomer is less, and the silicic acid monomer and the first step reaction act together to reduce the number of hydroxyl on the surface of silicon dioxide particles and reduce the production cost of the silicon rubber. In addition, the temperature of the second reaction step is greater than 80 ℃, resulting in a significant reduction in bare and uncondensed Si-OH on the particle surface. And finally, under the condition that the pH value is 2.5-5.0, adding an organic silicon compound which accounts for 0.01-0.1% of the total dosage of the solid sodium silicate as an auxiliary agent to promote the organic silicon compound to be combined with hydroxyl on the surface of the silicon dioxide, so that the surface hydroxyl is passivated, and the hydroxyl content on the surface of the silicon dioxide is further reduced. At the same time, the acidic end point pH contributes to an increase in the specific surface area.
When the precipitated silica for the high-resilience silicone rubber provided by the invention is mixed with raw rubber to prepare the silicone rubber, the surface hydroxyl content of the silica is low, the free water combined on the surface of the particles is low, the particles are easy to disperse, and a cross-linked structure of a three-dimensional elastic network is formed, so that the resilience of the silicone rubber is good. Meanwhile, the precipitated silica for the high-resilience silicone rubber provided by the invention has the advantages of large specific surface area, good permeability and high transparency of the formed silicone rubber.
Compared with the prior art, the precipitated silica for high-resilience silicone rubber and the preparation method thereof provided by the invention have the following advantages:
(1) the precipitated silica for the high-resilience silicone rubber provided by the invention has abundant pore structures, large specific surface area, good permeability when being applied to the silicone rubber, and high transparency of the formed silicone rubber;
(2) the precipitated silica for the high-resilience silicone rubber provided by the invention has low surface hydroxyl content, is easy to disperse, can form a three-dimensional elastic network cross-linking structure, and can improve the resilience of the silicone rubber to 60-75% when being applied to the silicone rubber;
(3) the preparation process of the precipitated silica for the high-resilience silicone rubber provided by the invention is simple and environment-friendly, has lower production cost, and is easy to realize industrial production.
Detailed Description
The present invention will be further described below by way of specific embodiments, but the present invention is not limited to only the following examples. Various modifications may be made by those skilled in the art based on the basic idea of the invention, but it is within the scope of the invention as long as it does not depart from the basic idea of the invention.
Example 1 preparation method of precipitated silica for high-resilience silicone rubber
A preparation method of precipitated silica for high-resilience silicone rubber comprises the following steps:
s1, liquefying solid sodium silicate with the modulus of 1.5 at high temperature, and adding water to prepare a sodium silicate solution with the concentration of 2.0 mol/L;
s2, preparing a sulfuric acid solution with the concentration of 2.0 mol/L;
s3, adding 8m into the reaction kettle3Adding tap water, and adding 5m3Heating the sodium silicate solution prepared in the step S1 to 80 ℃, starting a stirring device, setting the stirring frequency to be 25Hz, and dripping the sulfuric acid solution prepared in the step S2 in a stirring state, wherein the dripping speed of the sulfuric acid solution is 3m3Controlling the pH value of the reaction end point to be 8.0;
s4, continuously adding the sodium silicate solution prepared in the step S1 and the sulfuric acid solution prepared in the step S2 into the reaction kettle in a stirring state at the same time, wherein the adding speed of the sodium silicate solution is 8m3The dropping speed of the sulfuric acid solution is 3m3H, controlling the pH value in the reaction process to be 8.0, and when the addition amount of the sodium silicate solution reaches 10m3Stopping adding the sodium silicate solution dropwise, continuing adding the sulfuric acid solution prepared in the step S2 dropwise until the pH value in the reaction system is 2.5, adding hydroxyl silicone oil with the total solid sodium silicate dosage of 0.01%, aging for 60min, and performing filter pressing to obtain a filter cake;
s5, smashing the filter cake prepared in the step S4, washing, then transporting the slurry to a thick slurry tank, adding a proper amount of water, uniformly stirring, adjusting the solid content of the thick slurry to 15%, spray drying, grinding and crushing, and controlling the particle size of D50 of silicon dioxide to be 10 microns.
Example 2 preparation method of precipitated silica for high-resilience silicone rubber
A preparation method of precipitated silica for high-resilience silicone rubber comprises the following steps:
s1, liquefying solid sodium silicate with the modulus of 3.5 at high temperature, and adding water to prepare a sodium silicate solution with the concentration of 3.0 mol/L;
s2, preparing a sulfuric acid solution with the concentration of 4.8 mol/L;
s3, adding 12m into the reaction kettle3Adding tap water, and adding 7.5m3Heating the sodium silicate solution prepared in the step S1 to 95 ℃, starting a stirring device, setting the stirring frequency to be 30Hz, and dripping the sulfuric acid solution prepared in the step S2 in a stirring state, wherein the dripping speed of the sulfuric acid solution is 8m3Controlling the pH value of the reaction end point to be 10.5;
s4, continuously adding the sodium silicate solution prepared in the step S1 and the sulfuric acid solution prepared in the step S2 into the reaction kettle in a stirring state at the same time, wherein the adding speed of the sodium silicate solution is 12m3The dropping speed of the sulfuric acid solution is 8m3H, controlling the pH value in the reaction process to be 10.5, and when the addition amount of the sodium silicate solution reaches 15m3In this case, the dropwise addition of the sodium silicate solution is stopped, and the process of step S2 is continuedAdding hydroxyl silicone oil with the total amount of solid sodium silicate being 0.1 percent into the obtained sulfuric acid solution until the pH value in the reaction system is 5.0, aging for 120min, and performing filter pressing to obtain a filter cake;
s5, smashing the filter cake prepared in the step S4, washing, then transporting the slurry to a thick slurry tank, adding a proper amount of water, uniformly stirring, adjusting the solid content of the thick slurry to be 20%, spray drying, grinding and crushing, and controlling the particle size of D50 of silicon dioxide to be 16 microns.
Example 3 preparation method of precipitated silica for high-resilience silicone rubber
A preparation method of precipitated silica for high-resilience silicone rubber comprises the following steps:
s1, liquefying solid sodium silicate with the modulus of 2.5 at high temperature, and adding water to prepare a sodium silicate solution with the concentration of 2.5 mol/L;
s2, preparing a sulfuric acid solution with the concentration of 3.2 mol/L;
s3, adding 10m into the reaction kettle3Adding tap water, and adding 6.1m3Heating the sodium silicate solution prepared in the step S1 to 87 ℃, starting a stirring device, setting the stirring frequency to be 28Hz, and dripping the sulfuric acid solution prepared in the step S2 in a stirring state, wherein the dripping speed of the sulfuric acid solution is 6m3Controlling the pH value of the reaction end point to be 9.2;
s4, continuously adding the sodium silicate solution prepared in the step S1 and the sulfuric acid solution prepared in the step S2 into the reaction kettle in a stirring state at the same time, wherein the adding speed of the sodium silicate solution is 10m3H, the dropping speed of the sulfuric acid solution is 6m3H, controlling the pH value in the reaction process to be 9.2, and when the addition amount of the sodium silicate solution reaches 13m3Stopping adding the sodium silicate solution dropwise, continuing adding the sulfuric acid solution prepared in the step S2 dropwise until the pH value in the reaction system is 3.5, adding hydroxyl silicone oil with the total solid sodium silicate dosage of 0.07%, aging for 100min, and performing filter pressing to obtain a filter cake;
s5, smashing the filter cake prepared in the step S4, washing, then transporting the slurry to a thick slurry tank, adding a proper amount of water, uniformly stirring, adjusting the solid content of the thick slurry to 18%, spray drying, grinding and crushing, and controlling the particle size of D50 of silicon dioxide to be 14 microns.
Comparative example 1 preparation method of precipitated silica for high-resilience silicone rubber
The precipitated silica for high resilience silicone rubber described in this comparative example was prepared in a similar manner to example 3.
The difference between this comparative example and example 3 is: the concentration of the sodium silicate solution in step S1 in this comparative example was 1.0 mol/L.
Comparative example 2 preparation method of precipitated silica for high-resilience silicone rubber
The precipitated silica for high resilience silicone rubber described in this comparative example was prepared in a similar manner to example 3.
The difference between this comparative example and example 3 is: tap water was not added in step S3 of this comparative example.
Comparative example 3 preparation method of precipitated silica for high-resilience silicone rubber
The precipitated silica for high resilience silicone rubber described in this comparative example was prepared in a similar manner to example 3.
The difference between this comparative example and example 3 is: in the comparative example, the sodium silicate solution in the step S3 is added in a dropwise manner at a dropping speed of 6m3/h。
Comparative example 4 preparation method of precipitated silica for high-resilience silicone rubber
The precipitated silica for high resilience silicone rubber described in this comparative example was prepared in a similar manner to example 3.
The difference between this comparative example and example 3 is: in this comparative example, the pH of the acid-base co-drip process was controlled to 7.0 in step S4.
Comparative example 5 preparation method of precipitated silica for high-resilience silicone rubber
The precipitated silica for high resilience silicone rubber described in this comparative example was prepared in a similar manner to example 3.
The difference between this comparative example and example 3 is: in this comparative example, the addition of the sodium silicate solution was stopped in step S4, and the addition of the sulfuric acid solution was continued until the pH in the reaction system became 6.0.
Comparative example 6 preparation method of precipitated silica for high-resilience silicone rubber
The precipitated silica for high resilience silicone rubber described in this comparative example was prepared in a similar manner to example 3.
The difference between this comparative example and example 3 is: in this comparative example, no hydroxy silicone oil was added in step S4.
Test example I, Performance test
Test samples: precipitated silica for high resilience silicone rubber obtained in examples 1 to 3 and comparative examples 1 to 6;
the test method comprises the following steps: measuring the specific surface area of the test sample by using a specific surface instrument (JW-RB 12, Beijing Jingmigaokaokouchi technologies Co., Ltd.); measuring the D50 particle size of a test sample by using a laser particle sizer (JX 93/M337792, Beijing, Western and Western technologies, Ltd.); the oil absorption value is measured according to HG/T3072 and 2019 determination of oil absorption value of rubber compounding agent precipitated hydrated silica;
and (3) test results: the test results are shown in Table 1.
Table 1 silica performance test results
As can be seen from Table 1, the specific surface area of the precipitated silica for high-resilience silicone rubber provided by the invention is 150-210m2The particle size of D50 is 10-16 μm, and the oil absorption value is 150-210mL/100 g. The precipitated silica for high-resilience silicone rubber obtained in example 3 has the largest specific surface area and the highest oil absorption value, and is the best example of the present invention.
Compared with the embodiment 3, the step S3 in the comparative example 3 changes the adding mode of the sodium silicate solution, so that the pH value at the initial stage of the acid-base reaction is reduced, and the specific surface area of the prepared silicon dioxide is greatly reduced; comparative example 5 changed the pH at the end of the reaction in step S4, but the specific surface area of the produced silica was greatly reduced, which indicates that the acidic end pH contributed to increase the specific surface area.
Test example two, application Performance test
Test samples: precipitated silica for high resilience silicone rubber obtained in examples 1 to 3 and comparative examples 1 to 6;
the test method comprises the following steps: preparing a test sample into silicon rubber, cutting the silicon rubber into a test block with the thickness of 10mm, testing the resilience of the test block by using a rebound tester, and observing the transparency of the test block;
the silicon rubber formula comprises: 100 parts of raw methyl vinyl silicone rubber, 50 parts of a test sample, 2 parts of hydroxyl silicone oil, 30 parts of methyl silicone oil, 0.5 part of zinc stearate, 15 parts of vinyl silicone resin, 0.6 part of platinum catalyst and 0.5 part of organohydrogenpolysiloxane.
And (3) test results: the test results are shown in Table 2.
Table 2 silica application performance test results
As can be seen from Table 2, the rebound resilience of the silicon rubber in the application of the precipitated silica for high-resilience silicone rubber provided by the invention to silicone rubber is 60-75%, and the transparency is better. Among them, the silica obtained in example 3 has the best rebound resilience when applied to silicone rubber, and is the best embodiment of the present invention.
Compared with example 3, the silica prepared in comparative example 1 has poor rebound resilience when applied to silicone rubber, which indicates that the high-concentration sodium silicate solution is beneficial to improving the collision among silica particles during dehydration condensation and reducing the number of exposed hydroxyl groups on the particle surface; the transparency of the silica prepared in comparative example 2 applied to silicone rubber was slightly lowered; the transparency of the silicon dioxide prepared in the comparative example 3 applied to the silicon rubber is greatly reduced, which shows that the silicon dioxide particles generated under the strong alkali condition have large specific surface area and good permeability, and the formed silicon rubber has high transparency; the rebound resilience of the silicon dioxide prepared in the comparative example 4 applied to the silicon rubber is greatly reduced, which shows that the content of hydroxyl on the surface of the silicic acid monomer is less under the alkaline condition; the silica prepared in comparative example 5 has reduced rebound resilience and reduced transparency, which shows that the silica can be promoted to be combined with hydroxyl on the surface of the organosilicon compound under acidic conditions, the content of the hydroxyl on the surface of the silica is reduced, and the specific surface area of the silica is increased; the silicon dioxide prepared in the comparative example 6 has reduced rebound resilience when applied to silicon rubber, which shows that the organosilicon compound can be combined with hydroxyl on the surface of the silicon dioxide, the content of the hydroxyl on the surface of the silicon dioxide is reduced, and the rebound resilience of the silicon rubber is improved.
The above examples are merely illustrative of the preparation process of the present invention and do not limit the invention. Those skilled in the art will recognize that changes may be made to the embodiments described above without departing from the spirit and scope of the invention. Therefore, it is intended that all equivalent modifications or changes which can be made by those skilled in the art without departing from the technical spirit of the present invention are covered by the claims of the present invention.
Claims (9)
1. A preparation method of precipitated silica for high-resilience silicone rubber is characterized by comprising the following steps:
s1, liquefying solid sodium silicate at high temperature, and adding water to prepare a sodium silicate solution with the concentration of 2.0-3.0 mol/L;
s2, preparing a sulfuric acid solution with the concentration of 2.0-4.8 mol/L;
s3, adding tap water into the reaction kettle, then adding the sodium silicate solution prepared in the step S1, heating to 80-95 ℃, starting a stirring device, dropwise adding the sulfuric acid solution prepared in the step S2 under the stirring state, and controlling the pH value of the reaction end point to be 8.0-10.5;
s4, continuously adding the sodium silicate solution prepared in the step S1 and the sulfuric acid solution prepared in the step S2 dropwise into the reaction kettle at the same time under the stirring state, controlling the pH value in the reaction process to be 8.0-10.5, stopping adding the sodium silicate solution dropwise when the adding amount of the sodium silicate solution reaches a preset amount, continuously adding the sulfuric acid solution prepared in the step S2 dropwise until the pH value in the reaction system is 2.5-5.0, adding an organic silicon compound, aging for 60-120min, and performing filter pressing to obtain a filter cake;
s5, smashing the filter cake prepared in the step S4, washing, transporting the slurry to a thick slurry tank, adding a proper amount of water, uniformly stirring, adjusting the solid content of the thick slurry to 15-20%, spray drying, grinding and crushing to obtain the high-performance high-efficiency high-.
2. The method of preparing a precipitated silica for high resilience silicone rubber according to claim 1, wherein the modulus of the solid sodium silicate in step S1 is 1.5 to 3.5.
3. The method for preparing a precipitated silica for high-resilience silicone rubber according to claim 1, wherein the amount of tap water added in step S3 is 8 to 12m3The addition amount of sodium silicate is 5-7.5m3。
4. The method for producing a precipitated silica for high-resilience silicone rubber according to claim 1, wherein the stirring frequency of the stirring device in step S3 is 25 to 30Hz, and the dropping speed of the sulfuric acid solution is 3 to 8m3/h。
5. The method for producing a precipitated silica for high-resilience silicone rubber according to claim 1, wherein the dropping speed of the sodium silicate solution in the step S4 is 8 to 12m3The dropping speed of the sulfuric acid solution is 3-8m3/h。
6. The method for preparing precipitated silica for high resilience silicone rubber according to claim 1, wherein the predetermined amount of sodium silicate solution in the step S4 is 10 to 15m3。
7. The method of preparing a precipitated silica for high resilience silicone rubber according to claim 1, wherein the organosilicon compound in step S4 is a hydroxy silicone oil, and the amount of the organosilicon compound added is 0.01 to 0.1% of the total amount of solid sodium silicate used.
8. The method for producing a precipitated silica for high-resilience silicone rubber according to claim 1, wherein the D50 particle diameter of the silica is controlled to 10 to 16 μm at the time of grinding and crushing in the step S5.
9. A precipitated silica for high-resilience silicone rubber produced by the method for producing a precipitated silica for high-resilience silicone rubber according to any one of claims 1 to 8.
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Cited By (3)
| Publication number | Priority date | Publication date | Assignee | Title |
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| CN114604874A (en) * | 2022-04-01 | 2022-06-10 | 金三江(肇庆)硅材料股份有限公司 | High-refraction macroporous precipitated silica for high-transparency silicone rubber and preparation method thereof |
| CN114956104A (en) * | 2022-07-28 | 2022-08-30 | 广州市飞雪材料科技有限公司 | Silicon dioxide reinforcing agent for silicon rubber and preparation method thereof |
| CN115724432A (en) * | 2022-11-21 | 2023-03-03 | 华南理工大学 | High-permeability high-reinforcement precipitated white carbon black for high-temperature vulcanized silicone rubber and preparation method and application thereof |
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| CN114956104A (en) * | 2022-07-28 | 2022-08-30 | 广州市飞雪材料科技有限公司 | Silicon dioxide reinforcing agent for silicon rubber and preparation method thereof |
| CN115724432A (en) * | 2022-11-21 | 2023-03-03 | 华南理工大学 | High-permeability high-reinforcement precipitated white carbon black for high-temperature vulcanized silicone rubber and preparation method and application thereof |
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