CN113337243A - Sealing silica gel and preparation method thereof - Google Patents
Sealing silica gel and preparation method thereof Download PDFInfo
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- CN113337243A CN113337243A CN202110548276.3A CN202110548276A CN113337243A CN 113337243 A CN113337243 A CN 113337243A CN 202110548276 A CN202110548276 A CN 202110548276A CN 113337243 A CN113337243 A CN 113337243A
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- C—CHEMISTRY; METALLURGY
- C09—DYES; PAINTS; POLISHES; NATURAL RESINS; ADHESIVES; COMPOSITIONS NOT OTHERWISE PROVIDED FOR; APPLICATIONS OF MATERIALS NOT OTHERWISE PROVIDED FOR
- C09J—ADHESIVES; NON-MECHANICAL ASPECTS OF ADHESIVE PROCESSES IN GENERAL; ADHESIVE PROCESSES NOT PROVIDED FOR ELSEWHERE; USE OF MATERIALS AS ADHESIVES
- C09J183/00—Adhesives based on macromolecular compounds obtained by reactions forming in the main chain of the macromolecule a linkage containing silicon, with or without sulfur, nitrogen, oxygen, or carbon only; Adhesives based on derivatives of such polymers
- C09J183/04—Polysiloxanes
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- C—CHEMISTRY; METALLURGY
- C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
- C08J—WORKING-UP; GENERAL PROCESSES OF COMPOUNDING; AFTER-TREATMENT NOT COVERED BY SUBCLASSES C08B, C08C, C08F, C08G or C08H
- C08J9/00—Working-up of macromolecular substances to porous or cellular articles or materials; After-treatment thereof
- C08J9/30—Working-up of macromolecular substances to porous or cellular articles or materials; After-treatment thereof by mixing gases into liquid compositions or plastisols, e.g. frothing with air
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- C—CHEMISTRY; METALLURGY
- C09—DYES; PAINTS; POLISHES; NATURAL RESINS; ADHESIVES; COMPOSITIONS NOT OTHERWISE PROVIDED FOR; APPLICATIONS OF MATERIALS NOT OTHERWISE PROVIDED FOR
- C09J—ADHESIVES; NON-MECHANICAL ASPECTS OF ADHESIVE PROCESSES IN GENERAL; ADHESIVE PROCESSES NOT PROVIDED FOR ELSEWHERE; USE OF MATERIALS AS ADHESIVES
- C09J11/00—Features of adhesives not provided for in group C09J9/00, e.g. additives
- C09J11/02—Non-macromolecular additives
- C09J11/04—Non-macromolecular additives inorganic
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- C—CHEMISTRY; METALLURGY
- C09—DYES; PAINTS; POLISHES; NATURAL RESINS; ADHESIVES; COMPOSITIONS NOT OTHERWISE PROVIDED FOR; APPLICATIONS OF MATERIALS NOT OTHERWISE PROVIDED FOR
- C09J—ADHESIVES; NON-MECHANICAL ASPECTS OF ADHESIVE PROCESSES IN GENERAL; ADHESIVE PROCESSES NOT PROVIDED FOR ELSEWHERE; USE OF MATERIALS AS ADHESIVES
- C09J11/00—Features of adhesives not provided for in group C09J9/00, e.g. additives
- C09J11/02—Non-macromolecular additives
- C09J11/06—Non-macromolecular additives organic
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- C—CHEMISTRY; METALLURGY
- C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
- C08J—WORKING-UP; GENERAL PROCESSES OF COMPOUNDING; AFTER-TREATMENT NOT COVERED BY SUBCLASSES C08B, C08C, C08F, C08G or C08H
- C08J2383/00—Characterised by the use of macromolecular compounds obtained by reactions forming in the main chain of the macromolecule a linkage containing silicon with or without sulfur, nitrogen, oxygen, or carbon only; Derivatives of such polymers
- C08J2383/04—Polysiloxanes
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- C—CHEMISTRY; METALLURGY
- C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
- C08J—WORKING-UP; GENERAL PROCESSES OF COMPOUNDING; AFTER-TREATMENT NOT COVERED BY SUBCLASSES C08B, C08C, C08F, C08G or C08H
- C08J2483/00—Characterised by the use of macromolecular compounds obtained by reactions forming in the main chain of the macromolecule a linkage containing silicon with or without sulfur, nitrogen, oxygen, or carbon only; Derivatives of such polymers
- C08J2483/04—Polysiloxanes
- C08J2483/07—Polysiloxanes containing silicon bound to unsaturated aliphatic groups
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- C—CHEMISTRY; METALLURGY
- C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
- C08L—COMPOSITIONS OF MACROMOLECULAR COMPOUNDS
- C08L2201/00—Properties
- C08L2201/08—Stabilised against heat, light or radiation or oxydation
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- C—CHEMISTRY; METALLURGY
- C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
- C08L—COMPOSITIONS OF MACROMOLECULAR COMPOUNDS
- C08L2205/00—Polymer mixtures characterised by other features
- C08L2205/02—Polymer mixtures characterised by other features containing two or more polymers of the same C08L -group
- C08L2205/025—Polymer mixtures characterised by other features containing two or more polymers of the same C08L -group containing two or more polymers of the same hierarchy C08L, and differing only in parameters such as density, comonomer content, molecular weight, structure
Abstract
The invention relates to sealing silica gel and a preparation method thereof, belonging to the technical field of electronic sealant preparation. The invention takes sepiolite fibers as raw materials, magnesium is dissolved out by destroying a magnesium-oxygen octahedral layer part through acid leaching modification, thereby increasing the pore path volume and porosity of the sepiolite fibers, then sodium silicate is adsorbed by utilizing the modified sepiolite fibers, the sodium silicate is adsorbed and immobilized in the internal pores of the modified sepiolite fibers, then the modified sepiolite fibers adsorbing the sodium silicate are put into hydrochloric acid, so that orthosilicic acid gel generated by the reaction of the hydrochloric acid and the sodium silicate is fixed in the internal pores of the sepiolite fibers, finally the sepiolite fibers are dried at high temperature, the water in the orthosilicic acid gel in the pores is evaporated, porous dry solid gel is fixed in the internal pores of the sepiolite fibers, finally the self-made thermal shock resistant heat dissipation filler is prepared, and the self-made foaming agent and the self-made thermal resistant antioxidant are matched, finally the sealing silica gel with high wear resistance, heat resistance and heat dissipation is prepared, the use effect is excellent.
Description
Technical Field
The invention relates to sealing silica gel and a preparation method thereof, belonging to the technical field of electronic sealant preparation.
Background
In the electronics field, it is important to protect many sensitive circuits and components, which are delicate and highly demanding, reliably for a long time. Epoxy resin and polyurethane are greatly influenced by external environment in application, particularly are obviously influenced by external temperature, the epoxy resin is very easy to embrittle, the polyurethane has defects in high temperature resistance, the structure is unstable, and the electronic silica gel has the greatest advantage of temperature stability compared with the two products, so that good physical and electrical properties can be kept in a wider temperature and humidity range, and therefore, the electronic silica gel is usually used as an electric insulator, and electrons are not easily influenced and polluted by the environment;
however, the existing electronic silica gel has poor mechanical properties, poor wear resistance, poor heat dissipation and poor heat resistance, so that the application of the electronic silica gel is limited.
In view of the above-mentioned drawbacks, the designer actively makes research and innovation to create a sealing silica gel and a preparation method thereof, so that the sealing silica gel has industrial value.
Disclosure of Invention
The technical problem to be solved by the invention is as follows: the existing electronic silica gel has poor mechanical property, poor wear resistance, poor heat dissipation and poor heat resistance, so that the application of the existing electronic silica gel is limited.
The invention relates to a sealing silica gel, which comprises the following raw materials in parts by weight:
25-29 parts of vinyl silicone resin;
3-7 parts of a self-made foaming agent;
24-28 parts of methyl pyrrolidone;
41-45 parts of dihydroxy polydimethylsiloxane;
15-19 parts of vinyl silicone oil;
the self-made foaming agent is prepared by mixing and reacting tea polyphenol, sodium methyl silanol, tetramethyl tetravinylcyclotetrasiloxane and ethyl acetate. The hydrophobic vinyl surfactant is added into a silica gel matrix, and then is foamed after being kneaded, uniform air holes are formed inside the silica gel matrix, and the generation of the air holes enables a silica gel material to have the effect of buffering and pressure relief when being impacted by the outside.
Further, the raw materials comprise 18-22 parts by weight of self-made thermal shock resistant heat dissipation filler;
the self-made thermal shock resistant heat dissipation filler is prepared by mixing and soaking sepiolite fibers and hydrochloric acid, then carrying out ultrasonic reaction on the mixture and sodium silicate solution, then continuing to react with hydrochloric acid, and drying. The invention firstly takes sepiolite fiber as raw material, the magnesium oxide octahedral layer part is destroyed to dissolve out magnesium by acid leaching modification, thereby increasing the pore path volume and porosity of the sepiolite fiber, then the modified sepiolite fiber is used for absorbing sodium silicate, so that the sodium silicate is absorbed and immobilized in the internal pores of the modified sepiolite fiber, then the modified sepiolite fiber absorbing the sodium silicate is put into hydrochloric acid, so that the hydrochloric acid and the sodium silicate react to generate the ortho-silicic acid gel which is fixed in the internal pores of the sepiolite fiber, finally the sepiolite fiber is dried at high temperature, so that the water in the ortho-silicic acid gel in the pores is evaporated, the porous dry solid gel is fixed in the internal pores of the sepiolite fiber, finally the self-made thermal shock resistant heat dissipation filler is prepared, the silicic acid gel in the filler pores has extremely strong hygroscopicity, the moisture absorption performance of silica gel can be improved by the addition of the self-made thermal shock resistant heat dissipation filler, in addition, the self-made thermal shock resistant heat dissipation filler of the invention uses silicon dioxide as a main raw material, and is of a composite fiber structure rich in high-valence metal ion oxide, after the self-made thermal shock resistant heat dissipation filler is added into a silica gel matrix, the composite fiber structure is distributed in the silica gel matrix in a disordered network shape to form a cross-linked and diffused heat dissipation network, inorganic oxide fibers have strong heat conductivity, when the heat in the silica gel is increased, the inorganic oxide fibers can be smoothly emitted to the outside from the inside of the silica gel through an excellent heat conductor, so that the heat dissipation performance of the silica gel is greatly improved, in addition, the heat resistance of the sepiolite fibers on the silica gel is obviously improved as an inorganic heat-resistant body, high-valence ions in the sepiolite fibers can capture free radicals generated in the high-temperature oxidation process of the silica gel, so that the free radicals generate inactive R +, so as to prevent the continuous proceeding of chain growth reaction, and the generated low-valence ions are oxidized to high valence ions by oxygen in the air, the cycle is repeated, the heat resistance of the silica gel is further improved, and the sepiolite fiber of the immobilized silica gel in the silica gel matrix can be used as a flexible unit toughening framework due to abundant surface pore structures and high length-diameter ratio and is coupled with the silica gel matrix, so that when the silica gel material is subjected to friction impact, the soft phase is subjected to stress to generate partial deformation and consume partial friction stress, the friction impact damage is weakened, and the wear resistance and the impact resistance of the silica gel are greatly improved; in addition, the porous structure on the surface of the sepiolite fiber increases physical anchoring points between the sepiolite fiber and the silica gel matrix, and the bonding stability between the silica gel molecules of the anchoring interfaces and the sepiolite fiber is lower than that of chemical bonding, but the bonding mode with relatively reduced stability ensures that when the rubber material is impacted by friction stress or thermal stress in the later period, relative slippage and deformation buffering can be generated on the material anchoring interface and the rubber material is displaced along the stress direction, so that the consumption of the internal energy of the silica gel substrate is reduced, the abrasion and thermal shock damage of the silica gel material are reduced, and the abrasion resistance and the thermal shock resistance of the silica gel material are improved again;
further, 12-16 parts of a self-made heat-resistant antioxidant is also included;
the self-made heat-resistant antioxidant is prepared by mixing 2, 6-di-tert-butylphenol, diphenylamine, n-decane and di-tert-butyl peroxide with tea oil oleic acid and neopentyl glycol after reaction. The invention mixes the synthesized 2, 6 di-tert-butyl-4- (diphenylamine) phenol and vegetable oil acid to obtain the heat-resistant antioxidant, and after the heat-resistant antioxidant is added into a silica gel matrix, because vegetable oleic acid can generate oxidation reaction to generate alkyl free radical and alkyl peroxy radical under the action of factors such as high temperature and oxygen of the silica gel matrix, the alkyl radicals and peroxy radicals can further react with 2, 6-di-tert-butyl-4- (diphenylamino) phenol to generate nitrogen radicals and alcohol and acid compounds with lower activity, the nitrogen radicals become very stable under the influence of benzene ring conjugation effect, and do not have enough activity to react with vegetable oleic acid molecules, therefore, the silicon rubber material can only have chain termination reaction of free radicals with other active free radicals and peroxy radicals which can cause the oxidative aging of the silicon rubber, thereby improving the aging resistance of the silicon rubber material;
further, the paint comprises the following raw materials in parts by weight:
27 parts of vinyl silicone resin;
20 parts of self-made thermal shock resistant heat dissipation filler;
5 parts of a self-made foaming agent;
14 parts of self-made heat-resistant antioxidant;
26 parts of methylpyrrolidone;
43 parts of dihydroxypolydimethylsiloxane;
17 parts of vinyl silicone oil. The silica gel material has the best performance under the condition of the mixture ratio.
A preparation method of sealing silica gel comprises the following specific preparation steps:
(1) weighing 25-29 parts of vinyl silicone resin, 18-22 parts of self-made thermal shock resistant heat dissipation filler, 3-7 parts of self-made foaming agent, 12-16 parts of self-made heat resistant antioxidant, 24-28 parts of methyl pyrrolidone, 41-45 parts of dihydroxy polydimethylsiloxane and 15-19 parts of vinyl silicone oil in parts by weight;
(2) adding vinyl silicone resin, dihydroxy polydimethylsiloxane, vinyl silicone oil and methyl pyrrolidone into a kneading machine, mixing for 2-3 h at 80-100 ℃, continuously adding a self-made thermal shock resistant heat dissipation filler, a self-made foaming agent and a self-made heat-resistant antioxidant, kneading for 2-3 h at the temperature of 120 ℃, the rotating speed of 350r/min and the vacuum degree of 0.6-0.9 Mpa, removing the water of the system, and discharging to obtain the sealing silica gel.
Further, the preparation steps of the self-made thermal shock resistant heat dissipation filler are as follows:
(1) weighing sepiolite fibers and hydrochloric acid with the mass fraction of 20% according to the mass ratio of 1:10, mixing, putting into a stirring kettle, stirring and soaking at 56-59 ℃ for 8-10 h, filtering and separating after soaking to obtain filter cakes, putting the filter cakes into an oven, and drying at 200-220 ℃ for 1-2 h to obtain the modified sepiolite fibers;
(2) mixing the modified sepiolite fibers and a 30% sodium silicate solution according to a mass ratio of 1:10, placing the mixture into an ultrasonic oscillator, carrying out ultrasonic oscillation dipping for 2-3 h at a frequency of 25-35 kHz, filtering and separating after the ultrasonic oscillation dipping is finished to obtain filter residues, placing the filter residues into hydrochloric acid with the concentration of 0.5mol/L, carrying out immersion reaction for 1-2 h, filtering and separating after the reaction is finished to obtain filter cakes, placing the filter cakes into a drying oven, and drying at 200-205 ℃ for 3-5 h to obtain the self-made thermal shock resistant heat dissipation filler.
Further, the preparation steps of the self-made foaming agent are as follows:
according to the weight parts, 15-20 parts of tea polyphenol and 18-20 parts of sodium methylsiliconate are placed in a beaker, dehydrated for 1-3 hours in a boiling water bath, 10-15 parts of tetramethyltetravinylcyclotetrasiloxane is added, the dehydration is continued for 1-2 hours, the temperature is raised to 115-150 ℃ for reaction for 2-3 hours, then the temperature is reduced to 60-70 ℃, 18-21 parts of ethyl acetate is added for stirring and dissolving, then the mixture is washed with water until the pH value of the washing liquid is neutral, and the solvent is heated and evaporated to obtain the self-made foaming agent.
Further, the preparation method of the homemade heat-resistant antioxidant comprises the following steps:
(1) 2, 6-di-tert-butylphenol, diphenylamine and n-decane in a mass ratio of 4: 7: 20, mixing and adding into a reaction kettle, stirring and reacting for 3-4 h under the protection of nitrogen, heating to 140-160 ℃, adding di-tert-butyl peroxide accounting for 50% of the mass of the n-decyl alcohol into the reaction kettle, and continuously stirring and reacting for 3-4 h to obtain a reaction product;
(2) transferring the reaction product into a single-neck flask, installing a condensation reflux device, heating to 140-150 ℃, distilling for 1-2 h, naturally cooling to room temperature, carrying out freeze crystallization in absolute ethyl alcohol at-20-15 ℃ for 2-3 h, filtering to obtain a filter cake, washing the filter cake with n-decane for 3-5 times, and drying in an oven to obtain 2, 6 di-tert-butyl-4- (diphenylamino) phenol;
(3) uniformly mixing 2, 6-di-tert-butyl-4- (diphenylamino) phenol, tea oil oleic acid and neopentyl glycol according to the mass ratio of 10:5:17 to obtain the self-made heat-resistant antioxidant.
By the scheme, the invention at least has the following advantages:
(1) the invention firstly takes sepiolite fiber as raw material, the magnesium oxide octahedral layer part is destroyed to dissolve out magnesium by acid leaching modification, thereby increasing the pore path volume and porosity of the sepiolite fiber, then the modified sepiolite fiber is used for absorbing sodium silicate, so that the sodium silicate is absorbed and immobilized in the internal pores of the modified sepiolite fiber, then the modified sepiolite fiber absorbing the sodium silicate is put into hydrochloric acid, so that the hydrochloric acid and the sodium silicate react to generate the ortho-silicic acid gel which is fixed in the internal pores of the sepiolite fiber, finally the sepiolite fiber is dried at high temperature, so that the water in the ortho-silicic acid gel in the pores is evaporated, the porous dry solid gel is fixed in the internal pores of the sepiolite fiber, finally the self-made thermal shock resistant heat dissipation filler is prepared, the silicic acid gel in the filler pores has extremely strong hygroscopicity, the moisture absorption performance of silica gel can be improved by the addition of the self-made thermal shock resistant heat dissipation filler, in addition, the self-made thermal shock resistant heat dissipation filler of the invention uses silicon dioxide as a main raw material, and is of a composite fiber structure rich in high-valence metal ion oxide, after the self-made thermal shock resistant heat dissipation filler is added into a silica gel matrix, the composite fiber structure is distributed in the silica gel matrix in a disordered network shape to form a cross-linked and diffused heat dissipation network, inorganic oxide fibers have strong heat conductivity, when the heat in the silica gel is increased, the inorganic oxide fibers can be smoothly emitted to the outside from the inside of the silica gel through an excellent heat conductor, so that the heat dissipation performance of the silica gel is greatly improved, in addition, the heat resistance of the sepiolite fibers on the silica gel is obviously improved as an inorganic heat-resistant body, high-valence ions in the sepiolite fibers can capture free radicals generated in the high-temperature oxidation process of the silica gel, so that the free radicals generate inactive R +, so as to prevent the continuous proceeding of chain growth reaction, and the generated low-valence ions are oxidized to high valence ions by oxygen in the air, the cycle is repeated, the heat resistance of the silica gel is further improved, and the sepiolite fiber of the immobilized silica gel in the silica gel matrix can be used as a flexible unit toughening framework due to abundant surface pore structures and high length-diameter ratio and is coupled with the silica gel matrix, so that when the silica gel material is subjected to friction impact, the soft phase is subjected to stress to generate partial deformation and consume partial friction stress, the friction impact damage is weakened, and the wear resistance and the impact resistance of the silica gel are greatly improved; in addition, the porous structure on the surface of the sepiolite fiber increases physical anchoring points between the sepiolite fiber and the silica gel matrix, and the bonding stability between the silica gel molecules of the anchoring interfaces and the sepiolite fiber is lower than that of chemical bonding, but the bonding mode with relatively reduced stability ensures that when the rubber material is impacted by friction stress or thermal stress in the later period, relative slippage and deformation buffering can be generated on the material anchoring interface and the rubber material is displaced along the stress direction, so that the consumption of the internal energy of the silica gel substrate is reduced, the abrasion and thermal shock damage of the silica gel material are reduced, and the abrasion resistance and the thermal shock resistance of the silica gel material are improved again;
(2) the invention mixes the synthesized 2, 6 di-tert-butyl-4- (diphenylamine) phenol and vegetable oil acid to obtain the heat-resistant antioxidant, and after the heat-resistant antioxidant is added into a silica gel matrix, because vegetable oleic acid can generate oxidation reaction to generate alkyl free radical and alkyl peroxy radical under the action of factors such as high temperature and oxygen of the silica gel matrix, the alkyl radicals and peroxy radicals can further react with 2, 6-di-tert-butyl-4- (diphenylamino) phenol to generate nitrogen radicals and alcohol and acid compounds with lower activity, the nitrogen radicals become very stable under the influence of benzene ring conjugation effect, and do not have enough activity to react with vegetable oleic acid molecules, therefore, the silicon rubber material can only have chain termination reaction of free radicals with other active free radicals and peroxy radicals which can cause the oxidative aging of the silicon rubber, thereby improving the aging resistance of the silicon rubber material;
(3) the hydrophobic vinyl surfactant is added into a silica gel matrix, and then is foamed after being kneaded, uniform air holes are formed inside the silica gel matrix, and the generation of the air holes enables a silica gel material to have the effect of buffering and pressure relief when being impacted by the outside.
The foregoing is a summary of the present invention, and in order to provide a clear understanding of the technical means of the present invention and to be implemented in accordance with the present specification, the following is a detailed description of the preferred embodiments of the present invention.
Detailed Description
The following examples are given to further illustrate the embodiments of the present invention. The following examples are intended to illustrate the invention but are not intended to limit the scope of the invention.
(1) Weighing sepiolite fibers and hydrochloric acid with the mass fraction of 20% according to the mass ratio of 1:10, mixing, putting into a stirring kettle, stirring and soaking at 56-59 ℃ for 8-10 h, filtering and separating after soaking to obtain filter cakes, putting the filter cakes into an oven, and drying at 200-220 ℃ for 1-2 h to obtain the modified sepiolite fibers; the method comprises the steps of firstly, taking sepiolite fibers as raw materials, and modifying the sepiolite fibers by acid leaching to destroy a magnesium-oxygen octahedral layer part to dissolve out magnesium, so that the pore volume and porosity of the sepiolite fibers are increased;
(2) mixing the modified sepiolite fibers and a 30% sodium silicate solution according to a mass ratio of 1:10, placing the mixture into an ultrasonic oscillator, carrying out ultrasonic oscillation dipping for 2-3 h at a frequency of 25-35 kHz, filtering and separating after the ultrasonic oscillation dipping is finished to obtain filter residues, placing the filter residues into hydrochloric acid with a concentration of 0.5mol/L, carrying out immersion reaction for 1-2 h, filtering and separating after the reaction is finished to obtain filter cakes, placing the filter cakes into a drying oven, and drying at 200-205 ℃ for 3-5 h to obtain the self-made thermal shock resistant heat dissipation filler; then utilizing the modified sepiolite fiber to adsorb sodium silicate to make the sodium silicate be adsorbed and immobilized in the internal pores of the modified sepiolite fiber, then placing the modified sepiolite fiber adsorbing the sodium silicate into hydrochloric acid to make the hydrochloric acid and the sodium silicate react to generate orthosilicic acid gel which is fixed in the internal pores of the sepiolite fiber, finally drying the sepiolite fiber at high temperature to evaporate the water in the orthosilicic acid gel in the pores to form porous dried solid gel which is fixed in the internal pores of the sepiolite fiber, finally preparing the self-made thermal shock resistant heat dissipation filler, wherein the silicic acid gel fixed in the filler pores has strong hygroscopicity, the moisture resistance and the moisture absorption performance of the silica gel can be improved by adding the self-made thermal shock resistant heat dissipation filler, in addition, the self-made thermal shock resistant heat dissipation filler per se of the invention takes silica as the main raw material, is a composite fiber structure rich in high-valence metal ion oxide, and after being added into a silica gel matrix, the inorganic oxide fiber has strong heat conductivity, when the heat in the silica gel is increased, the inorganic oxide fiber can be smoothly emitted from the inside of the silica gel to the outside through a hot excellent conductor, so that the heat dissipation performance of the silica gel is greatly improved, in addition, the heat resistance of the sepiolite fiber serving as an inorganic heat-resistant body to the silica gel is obviously improved, high-valence ions in the sepiolite fiber can capture free radicals generated in the high-temperature oxidation process of the silica gel, so that the free radicals can generate inactive R +, the continuous proceeding of chain growth reaction can be prevented, and the generated low-valence ions are oxidized into high-valence ions by oxygen in the air, the cycle is carried out, the heat resistance of the silica gel is further improved, and the sepiolite fiber fixedly carrying the silica gel is in the silica gel matrix because the surface of rich pore structures, the length-diameter ratio is high, the flexible unit toughening framework can be used as a flexible unit toughening framework and coupled with a silica gel substrate, when a silica gel material is subjected to friction impact, the flexible unit is subjected to stress to generate partial deformation to consume partial friction stress, the friction impact damage is weakened, and the wear resistance and the impact resistance of the silica gel are greatly improved; in addition, the porous structure on the surface of the sepiolite fiber increases physical anchoring points between the sepiolite fiber and the silica gel matrix, and the bonding stability between the silica gel molecules of the anchoring interfaces and the sepiolite fiber is lower than that of chemical bonding, but the bonding mode with relatively reduced stability ensures that when the rubber material is impacted by friction stress or thermal stress in the later period, relative slippage and deformation buffering can be generated on the material anchoring interface and the rubber material is displaced along the stress direction, so that the consumption of the internal energy of the silica gel substrate is reduced, the abrasion and thermal shock damage of the silica gel material are reduced, and the abrasion resistance and the thermal shock resistance of the silica gel material are improved again;
(3) 2, 6-di-tert-butylphenol, diphenylamine and n-decane in a mass ratio of 4: 7: 20, mixing and adding into a reaction kettle, stirring and reacting for 3-4 h under the protection of nitrogen, heating to 140-160 ℃, adding di-tert-butyl peroxide accounting for 50% of the mass of the n-decyl alcohol into the reaction kettle, and continuously stirring and reacting for 3-4 h to obtain a reaction product;
(4) transferring the reaction product into a single-neck flask, installing a condensation reflux device, heating to 140-150 ℃, distilling for 1-2 h, naturally cooling to room temperature, carrying out freeze crystallization in absolute ethyl alcohol at-20-15 ℃ for 2-3 h, filtering to obtain a filter cake, washing the filter cake with n-decane for 3-5 times, and drying in an oven to obtain 2, 6 di-tert-butyl-4- (diphenylamino) phenol;
(5) uniformly mixing 2, 6-di-tert-butyl-4- (diphenylamino) phenol, tea oil oleic acid and neopentyl glycol according to the mass ratio of 10:5:17 to obtain a self-made heat-resistant antioxidant; the invention mixes the synthesized 2, 6 di-tert-butyl-4- (diphenylamine) phenol and vegetable oil acid to obtain the heat-resistant antioxidant, and after the heat-resistant antioxidant is added into a silica gel matrix, because vegetable oleic acid can generate oxidation reaction to generate alkyl free radical and alkyl peroxy radical under the action of factors such as high temperature and oxygen of the silica gel matrix, the alkyl radicals and peroxy radicals can further react with 2, 6-di-tert-butyl-4- (diphenylamino) phenol to generate nitrogen radicals and alcohol and acid compounds with lower activity, the nitrogen radicals become very stable under the influence of benzene ring conjugation effect, and do not have enough activity to react with vegetable oleic acid molecules, therefore, the silicon rubber material can only have chain termination reaction of free radicals with other active free radicals and peroxy radicals which can cause the oxidative aging of the silicon rubber, thereby improving the aging resistance of the silicon rubber material;
(6) taking 15-20 parts by weight of tea polyphenol and 18-20 parts by weight of sodium methylsiliconate, placing the tea polyphenol and the sodium methylsiliconate into a beaker, dehydrating the tea polyphenol and the sodium methylsiliconate in a boiling water bath for 1-3 hours, adding 10-15 parts by weight of tetramethyltetravinylcyclotetrasiloxane, continuously dehydrating the tea for 1-2 hours, heating the tea to 115-150 ℃, reacting the tea for 2-3 hours, cooling the tea to 60-70 ℃, adding 18-21 parts by weight of ethyl acetate, stirring and dissolving the tea, then washing the tea with water until the pH value of a washing solution is neutral, and heating and steaming the tea to remove a solvent to obtain a self-made foaming agent; the hydrophobic vinyl surfactant is added into a silica gel matrix, and then is foamed after being kneaded, uniform air holes are formed inside the silica gel matrix, and the generation of the air holes enables a silica gel material to have the effect of buffering and pressure relief when being impacted by the outside.
(7) Weighing 25-29 parts of vinyl silicone resin, 18-22 parts of self-made thermal shock resistant heat dissipation filler, 3-7 parts of self-made foaming agent, 12-16 parts of self-made heat resistant antioxidant, 24-28 parts of methyl pyrrolidone, 41-45 parts of dihydroxy polydimethylsiloxane and 15-19 parts of vinyl silicone oil in parts by weight;
(8) adding vinyl silicone resin, dihydroxy polydimethylsiloxane, vinyl silicone oil and methyl pyrrolidone into a kneading machine, mixing for 2-3 h at 80-100 ℃, continuously adding a self-made thermal shock resistant heat dissipation filler, a self-made foaming agent and a self-made heat-resistant antioxidant, kneading for 2-3 h at the temperature of 120 ℃, the rotating speed of 350r/min and the vacuum degree of 0.6-0.9 Mpa, removing the water of the system, and discharging to obtain the sealing silica gel.
Examples
Example 1
(1) Weighing sepiolite fibers and hydrochloric acid with the mass fraction of 20% according to the mass ratio of 1:10, mixing, putting into a stirring kettle, stirring and soaking at 59 ℃ for 10 hours, filtering and separating after soaking to obtain filter cakes, and putting the filter cakes into an oven to be dried at 220 ℃ for 2 hours to obtain modified sepiolite fibers;
(2) mixing the modified sepiolite fibers and a 30% sodium silicate solution in a mass ratio of 1:10, placing the mixture into an ultrasonic oscillator, carrying out ultrasonic oscillation dipping for 3 hours at the frequency of 35kHz, filtering and separating to obtain filter residues after the ultrasonic oscillation dipping is finished, placing the filter residues into hydrochloric acid with the concentration of 0.5mol/L, carrying out dipping reaction for 2 hours, filtering and separating to obtain filter cakes after the reaction is finished, placing the filter cakes into a drying oven, and drying for 5 hours at 205 ℃ to obtain the self-made thermal shock resistant heat dissipation filler;
(3) 2, 6-di-tert-butylphenol, diphenylamine and n-decane in a mass ratio of 4: 7: 20, mixing and adding into a reaction kettle, stirring and reacting for 4 hours under the protection of nitrogen, heating to 160 ℃, adding di-tert-butyl peroxide accounting for 50% of the mass of the n-decyl alcohol into the reaction kettle, and continuously stirring and reacting for 4 hours to obtain a reaction product;
(4) transferring the reaction product into a single-neck flask, installing a condensation reflux device, heating to 150 ℃, distilling for 2 hours, naturally cooling to room temperature, freezing and crystallizing for 3 hours in absolute ethyl alcohol at the temperature of-15 ℃, filtering to obtain a filter cake, washing the filter cake for 5 times by using n-decane, and then placing the filter cake in an oven for drying to obtain 2, 6 di-tert-butyl-4- (dianilino) phenol;
(5) uniformly mixing 2, 6-di-tert-butyl-4- (diphenylamino) phenol, tea oil oleic acid and neopentyl glycol according to the mass ratio of 10:5:17 to obtain a self-made heat-resistant antioxidant;
(6) according to the weight parts, 20 parts of tea polyphenol and 20 parts of sodium methylsiliconate are placed in a beaker, dehydrated for 3 hours in a boiling water bath, 15 parts of tetramethyltetravinylcyclotetrasiloxane is added, the dehydration is continued for 2 hours, the temperature is raised to 150 ℃ for reaction for 3 hours, then the temperature is reduced to 70 ℃, 21 parts of ethyl acetate is added for stirring and dissolving, then the mixture is washed by water until the pH value of a washing liquid is neutral, and the solvent is heated and evaporated to obtain the self-made foaming agent;
(7) weighing 25 parts of vinyl silicone resin, 18 parts of self-made thermal shock resistant heat dissipation filler, 3 parts of self-made foaming agent, 12 parts of self-made heat-resistant antioxidant, 24 parts of methyl pyrrolidone, 41 parts of dihydroxy polydimethylsiloxane and 15 parts of vinyl silicone oil in parts by weight;
(8) adding vinyl silicone resin, dihydroxy polydimethylsiloxane, vinyl silicone oil and methyl pyrrolidone into a kneading machine, mixing for 3h at 100 ℃, continuously adding self-made thermal shock resistant heat dissipation filler, self-made foaming agent and self-made heat-resistant antioxidant, kneading for 3h at the temperature of 120 ℃, the rotating speed of 350r/min and the vacuum degree of 0.9Mpa, removing the water of the system, and discharging to obtain the sealing silica gel.
Example 2
(1) Weighing sepiolite fibers and hydrochloric acid with the mass fraction of 20% according to the mass ratio of 1:10, mixing, putting into a stirring kettle, stirring and soaking at 59 ℃ for 10 hours, filtering and separating after soaking to obtain filter cakes, and putting the filter cakes into an oven to be dried at 220 ℃ for 2 hours to obtain modified sepiolite fibers;
(2) mixing the modified sepiolite fibers and a 30% sodium silicate solution in a mass ratio of 1:10, placing the mixture into an ultrasonic oscillator, carrying out ultrasonic oscillation dipping for 3 hours at the frequency of 35kHz, filtering and separating to obtain filter residues after the ultrasonic oscillation dipping is finished, placing the filter residues into hydrochloric acid with the concentration of 0.5mol/L, carrying out dipping reaction for 2 hours, filtering and separating to obtain filter cakes after the reaction is finished, placing the filter cakes into a drying oven, and drying for 5 hours at 205 ℃ to obtain the self-made thermal shock resistant heat dissipation filler;
(3) 2, 6-di-tert-butylphenol, diphenylamine and n-decane in a mass ratio of 4: 7: 20, mixing and adding into a reaction kettle, stirring and reacting for 4 hours under the protection of nitrogen, heating to 160 ℃, adding di-tert-butyl peroxide accounting for 50% of the mass of the n-decyl alcohol into the reaction kettle, and continuously stirring and reacting for 4 hours to obtain a reaction product;
(4) transferring the reaction product into a single-neck flask, installing a condensation reflux device, heating to 150 ℃, distilling for 2 hours, naturally cooling to room temperature, freezing and crystallizing for 3 hours in absolute ethyl alcohol at the temperature of-15 ℃, filtering to obtain a filter cake, washing the filter cake for 5 times by using n-decane, and then placing the filter cake in an oven for drying to obtain 2, 6 di-tert-butyl-4- (dianilino) phenol;
(5) uniformly mixing 2, 6-di-tert-butyl-4- (diphenylamino) phenol, tea oil oleic acid and neopentyl glycol according to the mass ratio of 10:5:17 to obtain a self-made heat-resistant antioxidant;
(6) according to the weight parts, 20 parts of tea polyphenol and 20 parts of sodium methylsiliconate are placed in a beaker, dehydrated for 3 hours in a boiling water bath, 15 parts of tetramethyltetravinylcyclotetrasiloxane is added, the dehydration is continued for 2 hours, the temperature is raised to 150 ℃ for reaction for 3 hours, then the temperature is reduced to 70 ℃, 21 parts of ethyl acetate is added for stirring and dissolving, then the mixture is washed by water until the pH value of a washing liquid is neutral, and the solvent is heated and evaporated to obtain the self-made foaming agent;
(7) weighing 26 parts of vinyl silicone resin, 19 parts of self-made thermal shock resistant heat dissipation filler, 4 parts of self-made foaming agent, 13 parts of self-made heat-resistant antioxidant, 25 parts of methyl pyrrolidone, 42 parts of dihydroxy polydimethylsiloxane and 16 parts of vinyl silicone oil in parts by weight;
(8) adding vinyl silicone resin, dihydroxy polydimethylsiloxane, vinyl silicone oil and methyl pyrrolidone into a kneading machine, mixing for 3h at 100 ℃, continuously adding self-made thermal shock resistant heat dissipation filler, self-made foaming agent and self-made heat-resistant antioxidant, kneading for 3h at the temperature of 120 ℃, the rotating speed of 350r/min and the vacuum degree of 0.9Mpa, removing the water of the system, and discharging to obtain the sealing silica gel.
Example 3
(1) Weighing sepiolite fibers and hydrochloric acid with the mass fraction of 20% according to the mass ratio of 1:10, mixing, putting into a stirring kettle, stirring and soaking at 59 ℃ for 10 hours, filtering and separating after soaking to obtain filter cakes, and putting the filter cakes into an oven to be dried at 220 ℃ for 2 hours to obtain modified sepiolite fibers;
(2) mixing the modified sepiolite fibers and a 30% sodium silicate solution in a mass ratio of 1:10, placing the mixture into an ultrasonic oscillator, carrying out ultrasonic oscillation dipping for 3 hours at the frequency of 35kHz, filtering and separating to obtain filter residues after the ultrasonic oscillation dipping is finished, placing the filter residues into hydrochloric acid with the concentration of 0.5mol/L, carrying out dipping reaction for 2 hours, filtering and separating to obtain filter cakes after the reaction is finished, placing the filter cakes into a drying oven, and drying for 5 hours at 205 ℃ to obtain the self-made thermal shock resistant heat dissipation filler;
(3) 2, 6-di-tert-butylphenol, diphenylamine and n-decane in a mass ratio of 4: 7: 20, mixing and adding into a reaction kettle, stirring and reacting for 4 hours under the protection of nitrogen, heating to 160 ℃, adding di-tert-butyl peroxide accounting for 50% of the mass of the n-decyl alcohol into the reaction kettle, and continuously stirring and reacting for 4 hours to obtain a reaction product;
(4) transferring the reaction product into a single-neck flask, installing a condensation reflux device, heating to 150 ℃, distilling for 2 hours, naturally cooling to room temperature, freezing and crystallizing for 3 hours in absolute ethyl alcohol at the temperature of-15 ℃, filtering to obtain a filter cake, washing the filter cake for 5 times by using n-decane, and then placing the filter cake in an oven for drying to obtain 2, 6 di-tert-butyl-4- (dianilino) phenol;
(5) uniformly mixing 2, 6-di-tert-butyl-4- (diphenylamino) phenol, tea oil oleic acid and neopentyl glycol according to the mass ratio of 10:5:17 to obtain a self-made heat-resistant antioxidant;
(6) according to the weight parts, 20 parts of tea polyphenol and 20 parts of sodium methylsiliconate are placed in a beaker, dehydrated for 3 hours in a boiling water bath, 15 parts of tetramethyltetravinylcyclotetrasiloxane is added, the dehydration is continued for 2 hours, the temperature is raised to 150 ℃ for reaction for 3 hours, then the temperature is reduced to 70 ℃, 21 parts of ethyl acetate is added for stirring and dissolving, then the mixture is washed by water until the pH value of a washing liquid is neutral, and the solvent is heated and evaporated to obtain the self-made foaming agent;
(7) weighing 27 parts of vinyl silicone resin, 20 parts of self-made thermal shock resistant heat dissipation filler, 5 parts of self-made foaming agent, 14 parts of self-made heat-resistant antioxidant, 26 parts of methyl pyrrolidone, 43 parts of dihydroxy polydimethylsiloxane and 17 parts of vinyl silicone oil in parts by weight;
(8) adding vinyl silicone resin, dihydroxy polydimethylsiloxane, vinyl silicone oil and methyl pyrrolidone into a kneading machine, mixing for 3h at 100 ℃, continuously adding self-made thermal shock resistant heat dissipation filler, self-made foaming agent and self-made heat-resistant antioxidant, kneading for 3h at the temperature of 120 ℃, the rotating speed of 350r/min and the vacuum degree of 0.9Mpa, removing the water of the system, and discharging to obtain the sealing silica gel.
Example 4
(1) Weighing sepiolite fibers and hydrochloric acid with the mass fraction of 20% according to the mass ratio of 1:10, mixing, putting into a stirring kettle, stirring and soaking at 59 ℃ for 10 hours, filtering and separating after soaking to obtain filter cakes, and putting the filter cakes into an oven to be dried at 220 ℃ for 2 hours to obtain modified sepiolite fibers;
(2) mixing the modified sepiolite fibers and a 30% sodium silicate solution in a mass ratio of 1:10, placing the mixture into an ultrasonic oscillator, carrying out ultrasonic oscillation dipping for 3 hours at the frequency of 35kHz, filtering and separating to obtain filter residues after the ultrasonic oscillation dipping is finished, placing the filter residues into hydrochloric acid with the concentration of 0.5mol/L, carrying out dipping reaction for 2 hours, filtering and separating to obtain filter cakes after the reaction is finished, placing the filter cakes into a drying oven, and drying for 5 hours at 205 ℃ to obtain the self-made thermal shock resistant heat dissipation filler;
(3) 2, 6-di-tert-butylphenol, diphenylamine and n-decane in a mass ratio of 4: 7: 20, mixing and adding into a reaction kettle, stirring and reacting for 4 hours under the protection of nitrogen, heating to 160 ℃, adding di-tert-butyl peroxide accounting for 50% of the mass of the n-decyl alcohol into the reaction kettle, and continuously stirring and reacting for 4 hours to obtain a reaction product;
(4) transferring the reaction product into a single-neck flask, installing a condensation reflux device, heating to 150 ℃, distilling for 2 hours, naturally cooling to room temperature, freezing and crystallizing for 3 hours in absolute ethyl alcohol at the temperature of-15 ℃, filtering to obtain a filter cake, washing the filter cake for 5 times by using n-decane, and then placing the filter cake in an oven for drying to obtain 2, 6 di-tert-butyl-4- (dianilino) phenol;
(5) uniformly mixing 2, 6-di-tert-butyl-4- (diphenylamino) phenol, tea oil oleic acid and neopentyl glycol according to the mass ratio of 10:5:17 to obtain a self-made heat-resistant antioxidant;
(6) according to the weight parts, 20 parts of tea polyphenol and 20 parts of sodium methylsiliconate are placed in a beaker, dehydrated for 3 hours in a boiling water bath, 15 parts of tetramethyltetravinylcyclotetrasiloxane is added, the dehydration is continued for 2 hours, the temperature is raised to 150 ℃ for reaction for 3 hours, then the temperature is reduced to 70 ℃, 21 parts of ethyl acetate is added for stirring and dissolving, then the mixture is washed by water until the pH value of a washing liquid is neutral, and the solvent is heated and evaporated to obtain the self-made foaming agent;
(7) weighing 28 parts of vinyl silicone resin, 21 parts of self-made thermal shock resistant heat dissipation filler, 6 parts of self-made foaming agent, 15 parts of self-made heat-resistant antioxidant, 27 parts of methyl pyrrolidone, 44 parts of dihydroxy polydimethylsiloxane and 18 parts of vinyl silicone oil in parts by weight;
(8) adding vinyl silicone resin, dihydroxy polydimethylsiloxane, vinyl silicone oil and methyl pyrrolidone into a kneading machine, mixing for 3h at 100 ℃, continuously adding self-made thermal shock resistant heat dissipation filler, self-made foaming agent and self-made heat-resistant antioxidant, kneading for 3h at the temperature of 120 ℃, the rotating speed of 350r/min and the vacuum degree of 0.9Mpa, removing the water of the system, and discharging to obtain the sealing silica gel.
Example 5
(1) Weighing sepiolite fibers and hydrochloric acid with the mass fraction of 20% according to the mass ratio of 1:10, mixing, putting into a stirring kettle, stirring and soaking at 59 ℃ for 10 hours, filtering and separating after soaking to obtain filter cakes, and putting the filter cakes into an oven to be dried at 220 ℃ for 2 hours to obtain modified sepiolite fibers;
(2) mixing the modified sepiolite fibers and a 30% sodium silicate solution in a mass ratio of 1:10, placing the mixture into an ultrasonic oscillator, carrying out ultrasonic oscillation dipping for 3 hours at the frequency of 35kHz, filtering and separating to obtain filter residues after the ultrasonic oscillation dipping is finished, placing the filter residues into hydrochloric acid with the concentration of 0.5mol/L, carrying out dipping reaction for 2 hours, filtering and separating to obtain filter cakes after the reaction is finished, placing the filter cakes into a drying oven, and drying for 5 hours at 205 ℃ to obtain the self-made thermal shock resistant heat dissipation filler;
(3) 2, 6-di-tert-butylphenol, diphenylamine and n-decane in a mass ratio of 4: 7: 20, mixing and adding into a reaction kettle, stirring and reacting for 4 hours under the protection of nitrogen, heating to 160 ℃, adding di-tert-butyl peroxide accounting for 50% of the mass of the n-decyl alcohol into the reaction kettle, and continuously stirring and reacting for 4 hours to obtain a reaction product;
(4) transferring the reaction product into a single-neck flask, installing a condensation reflux device, heating to 150 ℃, distilling for 2 hours, naturally cooling to room temperature, freezing and crystallizing for 3 hours in absolute ethyl alcohol at the temperature of-15 ℃, filtering to obtain a filter cake, washing the filter cake for 5 times by using n-decane, and then placing the filter cake in an oven for drying to obtain 2, 6 di-tert-butyl-4- (dianilino) phenol;
(5) uniformly mixing 2, 6-di-tert-butyl-4- (diphenylamino) phenol, tea oil oleic acid and neopentyl glycol according to the mass ratio of 10:5:17 to obtain a self-made heat-resistant antioxidant;
(6) according to the weight parts, 20 parts of tea polyphenol and 20 parts of sodium methylsiliconate are placed in a beaker, dehydrated for 3 hours in a boiling water bath, 15 parts of tetramethyltetravinylcyclotetrasiloxane is added, the dehydration is continued for 2 hours, the temperature is raised to 150 ℃ for reaction for 3 hours, then the temperature is reduced to 70 ℃, 21 parts of ethyl acetate is added for stirring and dissolving, then the mixture is washed by water until the pH value of a washing liquid is neutral, and the solvent is heated and evaporated to obtain the self-made foaming agent;
(7) weighing 29 parts of vinyl silicone resin, 22 parts of self-made thermal shock resistant heat dissipation filler, 7 parts of self-made foaming agent, 16 parts of self-made heat-resistant antioxidant, 28 parts of methyl pyrrolidone, 45 parts of dihydroxy polydimethylsiloxane and 19 parts of vinyl silicone oil in parts by weight;
(8) adding vinyl silicone resin, dihydroxy polydimethylsiloxane, vinyl silicone oil and methyl pyrrolidone into a kneading machine, mixing for 3h at 100 ℃, continuously adding self-made thermal shock resistant heat dissipation filler, self-made foaming agent and self-made heat-resistant antioxidant, kneading for 3h at the temperature of 120 ℃, the rotating speed of 350r/min and the vacuum degree of 0.9Mpa, removing the water of the system, and discharging to obtain the sealing silica gel.
Performance test
The performance of the sealing silica gels in examples 1 to 5 was tested, and the test results are shown in table 1:
detection method/test method
And (3) heat dissipation detection:
the heat conductivity coefficient of the silica gel is measured according to a standard test method of the heat transfer characteristic of the heat-conducting electric insulating material, namely ASTM D5470, and the larger the heat conductivity coefficient is, the better the heat dissipation performance is;
and (3) testing mechanical properties:
testing by using a universal mechanical testing machine;
and (3) detecting the thermal aging resistance:
respectively placing the silica gel at 100 ℃, 150 ℃ and 180 ℃ for thermal ageing for 100h, and detecting the mechanical property difference of the silica gel material after the thermal ageing treatment is finished, wherein the smaller the difference is, the better the thermal ageing resistance is;
and (3) wear resistance test:
the average relative volume abrasion loss (mm) specified in the measurement of the abrasion resistance of the vulcanized rubber or the thermoplastic rubber (rotating roller type abrasion machine method) in GB/T9867-2008 is adopted3) The wear resistance of the sealing silica gel material is characterized, and the larger the average relative volume abrasion loss is, the worse the wear resistance is.
TABLE 1 Performance test results
Comparing the experimental data in examples 1-5, it can be seen that the performance data of the silica gel in examples 1-3 gradually become better, but the performance of the silica gel begins to decline from example 4, and analyzing the material ratios in examples 1-5 can find that the ratios of the raw material components in examples 1-5 are gradually increased, but as the content of the raw material increases, the performances of the silica gel material are optimal under the condition of the ratio in example 3, thus laterally confirming that the technical solution of the present application is feasible and the raw material ratio in example 3 is optimal.
Comparative example
Comparative example 1: when the sealing silica gel is prepared, the self-made thermal shock resistant heat dissipation filler is not added into the raw materials, and the rest conditions and the component proportion are the same as those of the example 1;
comparative example 2: when the sealing silica gel is prepared, common silicon dioxide particles are used for replacing the self-made thermal shock resistant heat dissipation filler, and the rest conditions and the component proportion are the same as those of the example 1;
comparative example 3: when the sealing silica gel was prepared, the heat-resistant antioxidant of the present invention was not added, and the remaining conditions and component ratios were the same as in example 1;
comparative example 4: when the sealing silica gel is prepared, the self-made foaming agent is not added, and the rest conditions and the component proportion are the same as those of the example 1;
comparative example 5: when the sealing silica gel is prepared, a common sodium dodecyl sulfate foaming agent is used for replacing the self-made foaming agent, and the rest conditions and the component proportion are the same as those in the example 1;
performance test
The performance of the sealing silica gels of comparative examples 1 to 5 was tested, and the test results are shown in table 2:
detection method/test method
And (3) heat dissipation detection:
the heat conductivity coefficient of the silica gel is measured according to a standard test method of the heat transfer characteristic of the heat-conducting electric insulating material, namely ASTM D5470, and the larger the heat conductivity coefficient is, the better the heat dissipation performance is;
and (3) testing mechanical properties:
testing by using a universal mechanical testing machine;
and (3) detecting the thermal aging resistance:
respectively placing the silica gel at 100 ℃, 150 ℃ and 180 ℃ for thermal ageing for 100h, and detecting the mechanical property difference of the silica gel material after the thermal ageing treatment is finished, wherein the smaller the difference is, the better the thermal ageing resistance is;
and (3) wear resistance test:
the average relative volume abrasion loss (mm) specified in the measurement of the abrasion resistance of the vulcanized rubber or the thermoplastic rubber (rotating roller type abrasion machine method) in GB/T9867-2008 is adopted3) The wear resistance of the sealing silica gel material is characterized, and the larger the average relative volume abrasion loss is, the worse the wear resistance is.
Firstly, comparing the detection data of the comparative example 1 and the comparative example 2 with the data of the example 1, it can be seen that, because the self-made thermal shock resistant heat dissipation filler of the invention is not added in the raw materials when the comparative example 1 is used for preparing the sealing silica gel, the rest conditions and the component proportion are the same as those of the example 1; comparative example 2 in the preparation of sealing silica gel, ordinary silica particles were used in place of the self-made thermal shock resistant heat dissipating filler of the present invention, and the remaining conditions and component ratios were the same as in example 1; finally, the temperature resistance, the wear resistance and the heat dissipation performance of the silica gel in the comparative examples 1 and 2 are obviously reduced, and the performance of the silica gel in the comparative example 1 is obviously reduced, because the self-made thermal shock resistant heat dissipation filler of the invention takes the silica as the main raw material, has a composite fiber structure rich in high-valence metal ion oxide, is distributed in the silica gel matrix in a disordered network shape after being added into the silica gel matrix to form a cross-linked and diffused heat dissipation network, and the inorganic oxide fiber has strong heat conductivity, and can be smoothly dissipated from the inside of the silica gel to the outside through an excellent heat conductor of the inorganic oxide fiber when the heat in the silica gel is increased, so that the heat dissipation performance of the silica gel is greatly improved, in addition, the heat resistance of the sepiolite fiber as an inorganic heat-resistant body to the silica gel is obviously improved, and high-valence ions in the sepiolite fiber can capture free radicals generated in the high-temperature oxidation process of the silica gel, the generated inactive R + is used for preventing the continuous progress of chain growth reaction, and the generated low valence state ions are oxidized into high valence state ions by oxygen in the air, the circulation is carried out, so that the heat resistance of the silica gel is further improved, and the sepiolite fibers of the immobilized silica gel in the silica gel matrix can be used as a flexible unit toughening framework and coupled with the silica gel matrix due to abundant surface pore structures and high length-diameter ratio, when the silica gel material is subjected to friction impact, the soft phase is subjected to stress to generate partial deformation to consume partial friction stress, and the friction impact damage is weakened, so that the wear resistance and the impact resistance of the silica gel are greatly improved; in addition, the porous structure on the surface of the sepiolite fiber increases physical anchoring points between the sepiolite fiber and the silica gel matrix, and the bonding stability between the silica gel molecules of the anchoring interfaces and the sepiolite fiber is lower than that of chemical bonding, but the bonding mode with relatively reduced stability ensures that when the rubber material is impacted by friction stress or thermal stress in the later period, relative slippage and deformation buffering can be generated on the material anchoring interface and the rubber material is displaced along the stress direction, so that the consumption of the internal energy of the silica gel substrate is reduced, the abrasion and thermal shock damage of the silica gel material are reduced, and the abrasion resistance and the thermal shock resistance of the silica gel material are improved again; it was also laterally confirmed that the solution of the invention is practicable;
the test data of comparative example 3 was compared with that of example 1, and since comparative example 3 did not add the heat-resistant antioxidant of the present invention when preparing a sealing silica gel, the remaining conditions and component ratios were the same as those of example 1; the heat-resistant aging performance of the final silica gel is obviously reduced, and other performances are not obviously reduced because the heat-resistant antioxidant is obtained by mixing the synthesized 2, 6 di-tert-butyl-4- (dianilino) phenol and the vegetable oleic acid, after the heat-resistant antioxidant is added into the silica gel matrix, the vegetable oleic acid can generate oxidation reaction under the action of factors such as high temperature and oxygen of the silica gel matrix to generate alkyl free radicals and alkyl peroxy radicals, the alkyl and peroxy radicals of the alkyl free radicals can further react with the 2, 6 di-tert-butyl-4- (dianilino) phenol to generate nitrogen free radicals and alcohol and acid compounds with lower activity, the nitrogen free radicals are very stable under the influence of the conjugated effect of benzene rings, and do not have enough activity to react with vegetable oleic acid molecules, so that the heat-resistant antioxidant can only generate chain termination reaction of the free radicals with other active free radicals and peroxy radicals which can cause the oxidation aging of the silica gel, thereby improving the aging resistance of the silica gel material; this also demonstrates from the side that the solution according to the invention can be implemented.
Finally, comparing the performance detection data of the comparative example 4 and the comparative example 5 with the performance detection data of the example 1, wherein the comparative example 4 does not add the self-made foaming agent of the invention when preparing the sealing silica gel, and the rest conditions and the component proportion are the same as those of the example 1; comparative example 5 in the preparation of sealing silica gel, a common sodium dodecyl sulfate foaming agent was used in place of the self-made foaming agent of the present invention, and the other conditions and component ratios were the same as in example 1; the heat dissipation performance and the heat resistance of the final silica gel are obviously reduced, and the reduction of the comparative example 4 is more obvious, because the hydrophobic vinyl surfactant is prepared by the invention, and is added into the silica gel matrix, and is foamed after kneading, uniform air holes are generated inside, and the generation of the air holes enables the silica gel material to have the effect of buffering and pressure relief when being impacted by the outside.
The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention, it should be noted that, for those skilled in the art, many modifications and variations can be made without departing from the technical principle of the present invention, and these modifications and variations should also be regarded as the protection scope of the present invention.
Claims (8)
1. A kind of sealing silica gel, its characteristic lies in: the composite material comprises the following raw materials in parts by weight:
25-29 parts of vinyl silicone resin;
3-7 parts of a self-made foaming agent;
24-28 parts of methyl pyrrolidone;
41-45 parts of dihydroxy polydimethylsiloxane;
15-19 parts of vinyl silicone oil;
the self-made foaming agent is prepared by mixing and reacting tea polyphenol, sodium methyl silanol, tetramethyl tetravinylcyclotetrasiloxane and ethyl acetate.
2. A sealing silica gel according to claim 1, wherein: the raw materials also comprise 18-22 parts by weight of self-made thermal shock resistant heat dissipation filler;
the self-made thermal shock resistant heat dissipation filler is prepared by mixing and soaking sepiolite fibers and hydrochloric acid, then carrying out ultrasonic reaction on the mixture and sodium silicate solution, then continuing to react with hydrochloric acid, and drying.
3. A sealing silica gel according to claim 2, wherein: the raw materials also comprise 12-16 parts by weight of a self-made heat-resistant antioxidant;
the self-made heat-resistant antioxidant is prepared by mixing 2, 6-di-tert-butylphenol, diphenylamine, n-decane and di-tert-butyl peroxide with tea oil oleic acid and neopentyl glycol after reaction.
4. A sealing silica gel according to claim 3, wherein: the composite material comprises the following raw materials in parts by weight:
27 parts of vinyl silicone resin;
20 parts of self-made thermal shock resistant heat dissipation filler;
5 parts of a self-made foaming agent;
14 parts of self-made heat-resistant antioxidant;
26 parts of methylpyrrolidone;
43 parts of dihydroxypolydimethylsiloxane;
17 parts of vinyl silicone oil.
5. A preparation method of sealing silica gel is characterized by comprising the following specific preparation steps:
(1) weighing 25-29 parts of vinyl silicone resin, 18-22 parts of self-made thermal shock resistant heat dissipation filler, 3-7 parts of self-made foaming agent, 12-16 parts of self-made heat resistant antioxidant, 24-28 parts of methyl pyrrolidone, 41-45 parts of dihydroxy polydimethylsiloxane and 15-19 parts of vinyl silicone oil in parts by weight;
(2) adding vinyl silicone resin, dihydroxy polydimethylsiloxane, vinyl silicone oil and methyl pyrrolidone into a kneading machine, mixing for 2-3 h at 80-100 ℃, continuously adding a self-made thermal shock resistant heat dissipation filler, a self-made foaming agent and a self-made heat-resistant antioxidant, kneading for 2-3 h at the temperature of 120 ℃, the rotating speed of 350r/min and the vacuum degree of 0.6-0.9 Mpa, removing the water of the system, and discharging to obtain the sealing silica gel.
6. The method for preparing sealing silica gel according to claim 5, wherein: the preparation method of the self-made thermal shock resistant heat dissipation filler comprises the following steps:
(1) weighing sepiolite fibers and hydrochloric acid with the mass fraction of 20% according to the mass ratio of 1:10, mixing, putting into a stirring kettle, stirring and soaking at 56-59 ℃ for 8-10 h, filtering and separating after soaking to obtain filter cakes, putting the filter cakes into an oven, and drying at 200-220 ℃ for 1-2 h to obtain the modified sepiolite fibers;
(2) mixing the modified sepiolite fibers and a 30% sodium silicate solution according to a mass ratio of 1:10, placing the mixture into an ultrasonic oscillator, carrying out ultrasonic oscillation dipping for 2-3 h at a frequency of 25-35 kHz, filtering and separating after the ultrasonic oscillation dipping is finished to obtain filter residues, placing the filter residues into hydrochloric acid with the concentration of 0.5mol/L, carrying out immersion reaction for 1-2 h, filtering and separating after the reaction is finished to obtain filter cakes, placing the filter cakes into a drying oven, and drying at 200-205 ℃ for 3-5 h to obtain the self-made thermal shock resistant heat dissipation filler.
7. The method for preparing sealing silica gel according to claim 5, wherein: the preparation steps of the self-made foaming agent are as follows:
according to the weight parts, 15-20 parts of tea polyphenol and 18-20 parts of sodium methylsiliconate are placed in a beaker, dehydrated for 1-3 hours in a boiling water bath, 10-15 parts of tetramethyltetravinylcyclotetrasiloxane is added, the dehydration is continued for 1-2 hours, the temperature is raised to 115-150 ℃ for reaction for 2-3 hours, then the temperature is reduced to 60-70 ℃, 18-21 parts of ethyl acetate is added for stirring and dissolving, then the mixture is washed with water until the pH value of the washing liquid is neutral, and the solvent is heated and evaporated to obtain the self-made foaming agent.
8. The method for preparing sealing silica gel according to claim 5, wherein: the preparation steps of the self-made heat-resistant antioxidant are as follows:
(1) 2, 6-di-tert-butylphenol, diphenylamine and n-decane in a mass ratio of 4: 7: 20, mixing and adding into a reaction kettle, stirring and reacting for 3-4 h under the protection of nitrogen, heating to 140-160 ℃, adding di-tert-butyl peroxide accounting for 50% of the mass of the n-decyl alcohol into the reaction kettle, and continuously stirring and reacting for 3-4 h to obtain a reaction product;
(2) transferring the reaction product into a single-neck flask, installing a condensation reflux device, heating to 140-150 ℃, distilling for 1-2 h, naturally cooling to room temperature, carrying out freeze crystallization in absolute ethyl alcohol at-20-15 ℃ for 2-3 h, filtering to obtain a filter cake, washing the filter cake with n-decane for 3-5 times, and drying in an oven to obtain 2, 6 di-tert-butyl-4- (diphenylamino) phenol;
(3) uniformly mixing 2, 6-di-tert-butyl-4- (diphenylamino) phenol, tea oil oleic acid and neopentyl glycol according to the mass ratio of 10:5:17 to obtain the self-made heat-resistant antioxidant.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202110548276.3A CN113337243A (en) | 2021-05-19 | 2021-05-19 | Sealing silica gel and preparation method thereof |
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Cited By (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN115382888A (en) * | 2022-09-15 | 2022-11-25 | 滁州智慧城市环保科技有限责任公司 | Dioxin regulator for incineration plant |
| CN117229128A (en) * | 2023-11-13 | 2023-12-15 | 山东寿光鲁清石化有限公司 | Purification method of methyl tertiary butyl ether crude product |
| CN117624992A (en) * | 2024-01-25 | 2024-03-01 | 山东信泰节能科技股份有限公司 | Reflective heat-insulating stone-like paint |
Citations (10)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN105860537A (en) * | 2016-04-18 | 2016-08-17 | 山东船舶技术研究院 | High-flame-retardance organosilicon sponge body material and preparation method thereof |
| CN106084796A (en) * | 2016-06-21 | 2016-11-09 | 山东船舶技术研究院 | A kind of high fire-retardance organosilicon cavernosa material and preparation method thereof |
| CN106883605A (en) * | 2017-04-17 | 2017-06-23 | 穆琳瑛 | A kind of rubber-based antidetonation padded coaming and preparation method thereof |
| CN108165350A (en) * | 2017-12-06 | 2018-06-15 | 常州富思通管道有限公司 | A kind of preparation method of wear-resisting anti-oxidant lubricating oil |
| CN108485706A (en) * | 2018-03-30 | 2018-09-04 | 胡果青 | A kind of preparation method of oxidation inert type paraffin |
| CN109266006A (en) * | 2018-09-20 | 2019-01-25 | 陈太师 | A kind of preparation method of silicone sponge |
| CN109796622A (en) * | 2019-01-12 | 2019-05-24 | 高产明 | A kind of preparation method of heat-resisting Open-Cells Silicone Rubber Foam material |
| CN110117465A (en) * | 2019-04-30 | 2019-08-13 | 刘春英 | A kind of preparation method with venthole heat-resistant silicon rubber coating |
| CN110747041A (en) * | 2019-10-16 | 2020-02-04 | 余十轮 | Preparation method of high-temperature oxidation-resistant anti-corrosion antiwear agent |
| CN111117742A (en) * | 2019-12-25 | 2020-05-08 | 黄世杰 | Preparation method of anti-wear and anti-oxidation lubricating oil |
-
2021
- 2021-05-19 CN CN202110548276.3A patent/CN113337243A/en active Pending
Patent Citations (10)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN105860537A (en) * | 2016-04-18 | 2016-08-17 | 山东船舶技术研究院 | High-flame-retardance organosilicon sponge body material and preparation method thereof |
| CN106084796A (en) * | 2016-06-21 | 2016-11-09 | 山东船舶技术研究院 | A kind of high fire-retardance organosilicon cavernosa material and preparation method thereof |
| CN106883605A (en) * | 2017-04-17 | 2017-06-23 | 穆琳瑛 | A kind of rubber-based antidetonation padded coaming and preparation method thereof |
| CN108165350A (en) * | 2017-12-06 | 2018-06-15 | 常州富思通管道有限公司 | A kind of preparation method of wear-resisting anti-oxidant lubricating oil |
| CN108485706A (en) * | 2018-03-30 | 2018-09-04 | 胡果青 | A kind of preparation method of oxidation inert type paraffin |
| CN109266006A (en) * | 2018-09-20 | 2019-01-25 | 陈太师 | A kind of preparation method of silicone sponge |
| CN109796622A (en) * | 2019-01-12 | 2019-05-24 | 高产明 | A kind of preparation method of heat-resisting Open-Cells Silicone Rubber Foam material |
| CN110117465A (en) * | 2019-04-30 | 2019-08-13 | 刘春英 | A kind of preparation method with venthole heat-resistant silicon rubber coating |
| CN110747041A (en) * | 2019-10-16 | 2020-02-04 | 余十轮 | Preparation method of high-temperature oxidation-resistant anti-corrosion antiwear agent |
| CN111117742A (en) * | 2019-12-25 | 2020-05-08 | 黄世杰 | Preparation method of anti-wear and anti-oxidation lubricating oil |
Non-Patent Citations (1)
| Title |
|---|
| 幸松民 等: "《有机硅合成工艺及产品应用》", 30 September 2000, 化学工业出版社 * |
Cited By (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN115382888A (en) * | 2022-09-15 | 2022-11-25 | 滁州智慧城市环保科技有限责任公司 | Dioxin regulator for incineration plant |
| CN115382888B (en) * | 2022-09-15 | 2023-12-15 | 滁州智慧城市环保科技有限责任公司 | Dioxin regulator for incineration plant |
| CN117229128A (en) * | 2023-11-13 | 2023-12-15 | 山东寿光鲁清石化有限公司 | Purification method of methyl tertiary butyl ether crude product |
| CN117624992A (en) * | 2024-01-25 | 2024-03-01 | 山东信泰节能科技股份有限公司 | Reflective heat-insulating stone-like paint |
| CN117624992B (en) * | 2024-01-25 | 2024-04-12 | 山东信泰节能科技股份有限公司 | Reflective heat-insulating stone-like paint |
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