CN107892816B - Heat-conducting silicone grease composition with low oil separation degree and preparation method thereof - Google Patents
Heat-conducting silicone grease composition with low oil separation degree and preparation method thereof Download PDFInfo
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Abstract
The invention discloses a low oil separation degree heat-conducting silicone grease composition and a preparation method thereof, wherein the heat-conducting silicone grease composition comprises polysiloxane, heat-conducting filler and a super-dispersion surface modifier, the super-dispersion surface modifier is used for carrying out dispersion modification on the heat-conducting filler under a hydrodynamic cavitation condition, the application of a cavitation technology and a super-dispersant is combined, and the appropriate cavitation process condition and the category of the super-dispersant are adopted, so that the oil separation degree and the viscosity of the silicone grease can be further reduced, the stability of the silicone grease is improved, and high heat conductivity is obtained.
Description
Technical Field
The invention belongs to the field of thermal interface materials, relates to a heat-conducting silicone grease composition, and particularly relates to a heat-conducting silicone grease composition with low oil separation degree and a preparation method thereof.
Background
With the rapid development of electronic technology, the integration degree and the packing density of electronic components are continuously improved, which provides a strong use function and also leads to a sharp increase in operating power consumption and heat generation. There are very fine rugged gaps between the surface of the electronic component and the heat sink, if they are directly mounted together, the actual contact area is only 10% of the area of the heat sink base, and the rest are air gaps. Because air is a poor thermal conductor, the thermal contact resistance between the electronic component and the radiator is very large, which seriously hinders the heat conduction and finally causes the low efficiency of the radiator, the operation stability and the service life of the component are reduced at light rate, and the circuit damage and the system breakdown are caused at heavy rate. The gaps are filled with a thermal interface material with high thermal conductivity, air in the gaps is removed, an effective heat conduction channel is established between the electronic component and the radiator, the contact thermal resistance can be greatly reduced, and the effect of the radiator is fully exerted. The heat-conducting silicone grease is a high-heat-conducting insulating organic silicon material, is almost never cured, and can keep a grease state for a long time at the temperature of minus 50 ℃ to plus 230 ℃. Has excellent electrical insulation and thermal conductivity, and can be widely applied to various electronic products and electrical equipment.
The inventor extensively researches and researches to find that the commonly used heat-conducting silicone grease product is prepared by dry or wet modifying a spherical or irregular heat-conducting powder filler by using a traditional coupling agent and adding polyorganosiloxane and other auxiliary agents. However, the conventional coupling agent has poor compatibility with polyorganosiloxane, a lipophilic segment of the conventional coupling agent is short, and the winding strength and flexibility with a polyorganosiloxane molecular chain are limited, so that the dispersion stability of the inorganic filler cannot be effectively improved, and the filler is easy to generate secondary agglomeration and precipitation.
Cavitation is a new type of intensification technology, and is the phenomenon that microbubbles (also called gas nuclei) formed by vaporization of a liquid due to local low pressure in the liquid (lower than the saturated vapor pressure at the corresponding temperature) grow explosively and then collapse rapidly. The research shows that the local temperature in the bubble nucleus reaches 5000K and the pressure reaches 5.05X 107Pa, and strong shock waves and micro jet flow with the speed as high as 300-400 m/s, thereby initiating various cavitation effects, creating an extreme physical and chemical environment, effectively breaking up powder filler aggregates and strengthening the surface chemical modification reaction process. According to the cavitation generation method, there are mainly ultrasonic cavitation and hydrodynamic cavitation. Ultrasonic cavitation cannot be applied to the field of industrial production at present due to high energy consumption, small treatment capacity and the like, so that the cavitation technology in the invention refers to hydrodynamic cavitation if no special description is provided. The cavitation technology is used for dispersing and modifying powder filler particles, and the application report of the cavitation technology in the preparation of heat-conducting silicone grease is rare. The inventor finds that in the process of dispersing the heat-conducting silicone grease filler powder by adopting the cavitation technology, the surface modifying agents such as silane coupling agents and the like are degraded, so that the stability of the modified powder is poor.
The ultra-dispersed surface modifier is a novel high-efficiency polymer type dispersing auxiliary agent, the molecular weight is about tens of thousands to hundreds of thousands, the organized chain is longer, and the ultra-dispersed surface modifier adopts a relatively extended conformation in a dispersing medium to form a steric hindrance with enough thickness on the surface of solid particles so as to avoid the aggregation and agglomeration of filler particles. The molecular structure of the hyperdispersant is divided into two parts: wherein a part is an anchoring group, commonly represented by-NR2、-NR3、-OH、-COOH、-COO-、-SO3H. Polyamine, polyol, polyether, and the like, which are adsorbed on the surface of the heat conductive powder filler by hydrogen bonds, ionic bonds, van der waals forces, and the like; the other part is an organic chain which determines the compatibility with organic media, and commonly includes alkane chains, polyester chains, polyether chains, polyolefin chains, polyacrylate chains, and the like. In the prior art, as a hyperdispersant chain segment belongs to organic matters, the thermal conductivity is low (about 0.2W/m · K), and more interface thermal resistance is introduced while the steric hindrance is increased due to the chain segment length of the hyperdispersant, so that the thermal conductivity of the silicone grease is reduced, the actual application of the hyperdispersant to the thermal silicone grease is limited to a certain extent, and particularly when the chain segment length n of the hyperdispersant exceeds 20, the prepared thermal silicone grease has poorer performance than that of the thermal silicone grease prepared by using a conventional coupling agent.
Disclosure of Invention
Aiming at the problems in the prior art, the invention aims to provide a preparation method of a heat-conducting silicone grease composition and the prepared heat-conducting silicone grease composition, wherein the application of a cavitation technology and a hyperdispersant is combined, the appropriate cavitation process condition and hyperdispersant category are adopted, the efficient modification of the surface of a filler is realized, the oil separation degree and viscosity of the silicone grease can be further reduced, the stability of the silicone grease is improved, and the high heat conductivity is obtained.
In order to solve the technical problem, the invention adopts the technical scheme that:
a method for preparing a low oil separation heat-conducting silicone grease composition, which comprises polyorganosiloxane, a heat-conducting filler and a super-dispersion surface modifier, is characterized by comprising the following steps:
SS1, heating and drying the filler powder in a vacuum environment to obtain dry powder;
SS2, dissolving the dried powder obtained in the step SS1 in water or an organic solvent containing water, preferably one or a mixed solvent of absolute ethyl alcohol, isopropyl alcohol, acetone, deionized water and the like, then adding a super-dispersion surface modifier, and performing dispersion modification under a hydrodynamic cavitation condition to obtain modified filler powder, wherein the super-dispersion surface modifier comprises a high molecular polymer of a lipophilic group and an anchoring group, the lipophilic group is an alkane chain or a polyester chain, the anchoring group is a hydroxyl group or a carboxyl group, the length n of the lipophilic main carbon chain is 19-50, preferably 22-35, and the hydrodynamic cavitation condition is as follows: the content of the solid filler in the two-phase fluid is 15-30%, the inlet pressure range of the cavitation nozzle is 5-100 MPa, the outlet pressure range is-0.5-4 MPa, the inlet pressure range is more preferably 8-50 MPa, and the outlet pressure range is 0-1 MPa;
and SS3, uniformly mixing the polysiloxane and the modified heat-conducting powder filler obtained in the step SS2, and thinly passing the mixture for a plurality of times on a three-roll grinding machine to prepare the uniformly flowing heat-conducting silicone grease composition.
Preferably, in the step SS1, the filler powder is put into a vacuum drying oven, vacuumized, heated at 50-300 ℃ for 0.5-10 hours, and dried to obtain the dry powder.
Preferably, in the step SS2, the treatment time of hydrodynamic cavitation is 5-120 min, the cavitation treatment temperature is 10-70 ℃, and after the reaction is completed, the powder is dried at 90-200 ℃ for 0.5-4 hours, and finally the modified powder is obtained.
Preferably, in step SS2, the hydrodynamic cavitation nozzle is preferably in the form of a venturi or orifice plate.
Preferably, in step SS2, the conditions of the hydrodynamic cavitation process are: the solid filler content in the two-phase fluid is 15-30%, the inlet pressure range of the cavitation nozzle is 5-100 MPa, the outlet pressure range is-0.5-4 MPa, the inlet pressure range is more preferably 8-50 MPa, and the outlet pressure range is 0-1 MPa. When the inlet pressure is lower than 5MPa or the outlet pressure is higher than 1MPa, the cavitation strength is obviously reduced, and the superfine powder filler cannot be effectively dispersed; when the inlet pressure is higher than 50MPa or the outlet pressure is lower than 0MPa, the cavitation strength is too high, and the hyperdispersant is degraded in advance, so that the modification effect is reduced.
Preferably, in the step SS2, the number of times of the hydrodynamic cavitation cycle treatment is 2-8, preferably 3-5. If the treatment times are lower than the optimal range, the powder and the hyperdispersant are not completely treated, so that the thermal conductivity and the stability of the silicone grease are reduced; when the treatment times are higher than the preferable range, the hyperdispersant is degraded excessively, and the silicone grease is easy to agglomerate and settle.
Preferably, in step SS3, the polyorganosiloxane and the modified heat conductive powder filler are uniformly mixed and passed through a three-roll mill for 3-20 passes.
Preferably, in step SS3, when the polyorganosiloxane and the modified heat-conducting powder filler are mixed, the mass ratio of the polyorganosiloxane is 3% to 60%, and the rest is the modified heat-conducting powder filler.
Preferably, in step SS3, when the polyorganosiloxane and the modified thermal conductive powder filler are mixed, other additives such as antioxidant may be added.
Furthermore, in step SS3, when the polyorganosiloxane, the modified heat-conducting powder filler and the other additives are mixed, the mass ratio of the polyorganosiloxane is 3% -60%, the other additives are 0% -10%, and the rest is the modified heat-conducting powder filler.
According to another aspect of the invention, the invention also provides a low oil separation degree heat-conducting silicone grease composition obtained by the preparation method, which is characterized in that the heat-conducting silicone grease composition is prepared from at least the following raw materials in parts by mass:
(A) 3 to 60 percent of polyorganosiloxane
(B) 10 to 97 percent of heat-conducting filler
(C) 0.1 to 10 percent of ultra-dispersed surface modifier.
Preferably, the preparation raw materials of the heat-conducting silicone grease composition further comprise 0-10% of other auxiliary agents in parts by mass.
Preferably, the length n of the lipophilic main carbon chain segment of the super-dispersion surface modifier is 19-50, preferably 22-35. The super-dispersion surface modifier comprises a lipophilic group and a high molecular polymer of an anchoring group, wherein the lipophilic group is an alkane chain or a polyester chain, the anchoring group is a hydroxyl group or a carboxyl group, and the length n of the lipophilic main carbon chain is 19-50, preferably 22-35.
Preferably, the molecular formula structure of the ultra-disperse surface modifier is preferably:
preferably, the polysiloxane is one or a mixture of more than two of dimethyl silicone oil, methyl toluene silicone oil, vinyl silicone oil, fluorine hydrocarbon-based silicone oil or other modified silicone oil.
Further, the viscosity of the polyorganosiloxane ranges from 50 to 10000 cps.
Preferably, the heat conductive filler may be metal, inorganic material, and carbon material powder or a mixture thereof, including silver, copper, aluminum, iron, zinc, silver-coated copper, nickel-coated copper, white carbon, diamond, carbon black, graphite, carbon fiber, carbon nanotube, graphene, aluminum oxide, zinc oxide, magnesium oxide, aluminum nitride, silicon nitride, boron nitride, silicon carbide, and the like, but is not limited thereto.
More preferably, the heat conductive filler has a heat conductivity of 10 to 1000W/m.k and a particle diameter of 100nm to 100 μm.
Preferably, the other auxiliary agents include: coupling agent, antioxidant, colorant, antirust agent, etc.
Within the specific range of the invention, the hyper-dispersant and the cavitation technology are matched to fully play the synergistic effect of the hyper-dispersant and the cavitation technology, and compared with the prior art, the ultra-dispersant and the cavitation technology have the following main differences and advantages: (1) the powder agglomerated particles can be fully scattered by the hydrodynamic cavitation treatment within a specific parameter range; (2) under the optimized cavitation parameter, the hyperdispersant with specific chain segment length is partially degraded, namely the chain segment length of the dispersant on the surface of the powder is changed, and the un-degraded part of the chain segment keeps the original chain segment number due to the degradation effect of the partial chain segment is shortened, so that the long-short collocation is formed. Because the length of the chain segment is shortened, the thermal resistance is reduced, the thermal conductivity of the silicone grease is improved, and meanwhile, part of long chain segments play a role in steric hindrance, so that the stability of the silicone grease is ensured; (3) in the invention, the combination of the cavitation parameter and the chain segment length of the dispersing agent determines the performance of the silicone grease. When the inlet pressure is lower than 5MPa or the outlet pressure is higher than 1MPa, the cavitation strength is obviously reduced, the powder is not sufficiently dispersed, and the hyperdispersant cannot be partially degraded; when the inlet pressure is higher than 50MPa or the outlet pressure is lower than 0MPa, the cavitation strength is obviously increased, and the hyperdispersant is easily degraded excessively, so that the stability of the silicone grease is reduced. In the preferred treatment pressure range, the cavitation cycle treatment times are lower than the preferred 3 times, the treatment is insufficient, and the uneven powder dispersion and the insufficient degradation of the hyperdispersant are also caused; the cavitation cycle treatment times are higher than 5 times, so that the hyperdispersant is degraded excessively, and the silicone grease is easy to settle and agglomerate; the length n of the chain segment of the hyperdispersant is preferably 22-35, and is lower than the value, and after the hyperdispersant is partially degraded, the chain segment cannot form effective steric hindrance if the length of the chain segment is too short; above this value, the chain length is still too long after partial degradation of the hyperdispersant, resulting in too high a thermal resistance.
Detailed Description
Examples 1 to 4 and comparative examples 1 to 8 below, in which the molecular formula of the hyperdispersant is shown below but the invention is not limited to this structure, are used to describe the present invention in more detail.
Example 1
(A) The polysiloxane is 100g of dimethyl silicone oil; (B) the heat-conducting filler is 400g of zinc oxide, the average grain diameter is 8 mu m, 500g of aluminum powder, and the average grain diameter is 2 mu m; (C) ultra-dispersed surface modifier, 10g, wherein segment length n ═ 22; (D) not mixed in. The filler adopts a hydrodynamic cavitation treatment modification method: the inlet pressure of the cavitation nozzle is 10MPa, the outlet pressure of the nozzle is 0.8MPa, and the circulation treatment is carried out for 3 times. Other operation processes are described in the steps.
Example 2
(A) The polysiloxane is 100g of dimethyl silicone oil; (B) the heat-conducting filler is 400g of zinc oxide, the average grain diameter is 8 mu m, 500g of aluminum powder, and the average grain diameter is 2 mu m; (C) ultra-dispersed surface modifier, 10g, wherein segment length n ═ 22; (D) not mixed in. The filler adopts a hydrodynamic cavitation treatment modification method: the inlet pressure of the cavitation nozzle is 40MPa, the outlet pressure of the nozzle is 0.8MPa, and the circulation treatment is carried out for 3 times. Other operation processes are described in the steps.
Example 3
(A) The polysiloxane is 100g of dimethyl silicone oil; (B) the heat-conducting filler is 400g of zinc oxide, the average grain diameter is 8 mu m, 500g of aluminum powder, and the average grain diameter is 2 mu m; (C) ultra-dispersed surface modifier, 10g, wherein segment length n ═ 22; (D) not mixed in. The filler adopts a hydrodynamic cavitation treatment modification method: the inlet pressure of the cavitation nozzle is 40MPa, the outlet pressure of the nozzle is 0.2MPa, and the circulation treatment is carried out for 3 times. Other operation processes are described in the steps.
Example 4
(A) The polysiloxane is 100g of dimethyl silicone oil; (B) the heat-conducting filler is 400g of zinc oxide, the average grain diameter is 8 mu m, 500g of aluminum powder, and the average grain diameter is 2 mu m; (C) ultra-dispersed surface modifier, 10g, wherein segment length n ═ 22; (D) not mixed in. The filler adopts a hydrodynamic cavitation treatment modification method: the inlet pressure of the cavitation nozzle is 40MPa, the outlet pressure of the nozzle is 0.2MPa, and the circulation treatment is carried out for 5 times. Other operation processes are described in the steps.
Example 5
(A) The polysiloxane is 100g of dimethyl silicone oil; (B) the heat-conducting filler is 400g of zinc oxide, the average grain diameter is 8 mu m, 500g of aluminum powder, and the average grain diameter is 2 mu m; (C) 10g of ultra-disperse surface modifier, wherein the segment length n is 30; (D) not mixed in. The filler adopts a hydrodynamic cavitation treatment modification method: the inlet pressure of the cavitation nozzle is 40MPa, the outlet pressure of the nozzle is 0.2MPa, and the circulation treatment is carried out for 5 times. Other operation processes are described in the steps.
Comparative example 1
(A) The polysiloxane is 100g of dimethyl silicone oil; (B) the heat-conducting filler is 400g of zinc oxide, the average grain diameter is 8 mu m, 500g of aluminum powder, and the average grain diameter is 2 mu m; (C) ultra-dispersed surface modifier, 10g, wherein segment length n ═ 22; (D) not mixed in. The filler is modified by a traditional dry method, and the treatment time is 120 min. Other operation processes are described in the steps.
Comparative example 2
(A) The polysiloxane is 100g of dimethyl silicone oil; (B) the heat-conducting filler is 400g of zinc oxide, the average grain diameter is 8 mu m, 500g of aluminum powder, and the average grain diameter is 2 mu m; (C) ultra-dispersed surface modifier, 10g, wherein segment length n ═ 22; (D) not mixed in. The filler is modified by a traditional wet method, and the treatment time is 120 min. Other operation processes are described in the steps.
Comparative example 3
(A) The polysiloxane is 100g of dimethyl silicone oil; (B) the heat-conducting filler is 400g of zinc oxide, the average grain diameter is 8 mu m, 500g of aluminum powder, and the average grain diameter is 2 mu m; (C) 10g of ultra-dispersed surface modifier, wherein the segment length n is 10; (D) not mixed in. The filler adopts a hydrodynamic cavitation treatment modification method: the inlet pressure of the cavitation nozzle is 10MPa, the outlet pressure of the nozzle is 0.8MPa, and the circulation treatment is carried out for 3 times. Other operation processes are described in the steps.
Comparative example 4
(A) The polysiloxane is 100g of dimethyl silicone oil; (B) the heat-conducting filler is 400g of zinc oxide, the average grain diameter is 8 mu m, 500g of aluminum powder, and the average grain diameter is 2 mu m; (C) 10g of ultra-disperse surface modifier, wherein the segment length n is 45; (D) not mixed in. The filler adopts a hydrodynamic cavitation treatment modification method: the inlet pressure of the cavitation nozzle is 10MPa, the outlet pressure of the nozzle is 0.8MPa, and the circulation treatment is carried out for 3 times. Other operation processes are described in the steps.
Comparative example 5
(A) The polysiloxane is 100g of dimethyl silicone oil; (B) the heat-conducting filler is 400g of zinc oxide, the average grain diameter is 8 mu m, 500g of aluminum powder, and the average grain diameter is 2 mu m; (C) ultra-dispersed surface modifier, 10g, wherein segment length n ═ 22; (D) not mixed in. The filler adopts a hydrodynamic cavitation treatment modification method: the inlet pressure of the cavitation nozzle is 100MPa, the outlet pressure of the nozzle is 0.8MPa, and the circulation treatment is carried out for 3 times. Other operation processes are described in the steps.
Comparative example 6
(A) The polysiloxane is 100g of dimethyl silicone oil; (B) the heat-conducting filler is 400g of zinc oxide, the average grain diameter is 8 mu m, 500g of aluminum powder, and the average grain diameter is 2 mu m; (C) ultra-dispersed surface modifier, 10g, wherein segment length n ═ 22; (D) not mixed in. The filler adopts a hydrodynamic cavitation treatment modification method: the inlet pressure of the cavitation nozzle is 10MPa, the outlet pressure of the nozzle is 0.01MPa, and the circulation treatment is carried out for 3 times. Other operation processes are described in the steps.
Comparative example 7
(A) The polysiloxane is 100g of dimethyl silicone oil; (B) the heat-conducting filler is 400g of zinc oxide, the average grain diameter is 8 mu m, 500g of aluminum powder, and the average grain diameter is 2 mu m; (C) ultra-dispersed surface modifier, 10g, wherein segment length n ═ 22; (D) not mixed in. The filler adopts a hydrodynamic cavitation treatment modification method: the inlet pressure of the cavitation nozzle is 10MPa, the outlet pressure of the nozzle is 0.8MPa, and the circulation treatment is carried out for 10 times. Other operation processes are described in the steps.
Comparative example 8
(A) The polysiloxane is 100g of dimethyl silicone oil; (B) the heat-conducting filler is 400g of zinc oxide, the average grain diameter is 8 mu m, 500g of aluminum powder, and the average grain diameter is 2 mu m; (C) the dispersant is KH-570, 10 g; (D) not mixed in. The filler adopts a hydrodynamic cavitation treatment modification method: the inlet pressure of the cavitation nozzle is 10MPa, the outlet pressure of the nozzle is 0.8MPa, and the circulation treatment is carried out for 3 times. Other operation processes are described in the steps.
And (3) performance detection:
the thermal conductivity of the heat-conducting silicone grease is measured by adopting a DRL-III type thermal conductivity instrument, and the oil separation degree is measured by adopting a cone sieve method based on the ASTM D6184-1997 standard. The results of the thermal grease testing of the present invention are shown in Table 1
TABLE 1 test results of thermally conductive silicone grease
| Thermal conductivity W/(m.K) | Oil separation degree (%) | Viscosity mPas | |
| Example 1 | 3.35 | 0.52 | 89000 |
| Example 2 | 3.46 | 0.51 | 88000 |
| Example 3 | 3.51 | 0.57 | 92000 |
| Example 4 | 3.50 | 0.54 | 89000 |
| Example 5 | 3.32 | 0.46 | 82000 |
| Comparative example 1 | 2.95 | 0.31 | 91000 |
| Comparative example 2 | 3.02 | 0.29 | 89500 |
| Comparative example 3 | 2.92 | 0.32 | 91200 |
| Comparative example 4 | 2.82 | 0.26 | 83000 |
| Comparative example 5 | 3.62 | 1.08 | 118200 |
| Comparative example 6 | 3.53 | 0.88 | 105000 |
| Comparative example 7 | 3.41 | 0.61 | 95000 |
| Comparative example 8 | 3.39 | 0.96 | 112000 |
The above-mentioned embodiments further explain the objects, technical solutions and advantages of the present invention in detail. It should be understood that the above-mentioned embodiments are only exemplary of the present invention, and are not intended to limit the present invention, and any modification, equivalent replacement, or improvement made within the spirit and principle of the present invention should be included in the protection scope of the present invention.
Claims (10)
1. A method for preparing a low oil separation heat-conducting silicone grease composition, which comprises polyorganosiloxane, a heat-conducting filler and a super-dispersion surface modifier, is characterized by comprising the following steps:
SS1, heating and drying the filler powder in a vacuum environment to obtain dry powder;
SS2, dissolving the dried powder obtained in the step SS1 in water or an organic solvent containing water, then adding a super-dispersion surface modifier, and carrying out dispersion modification under a hydrodynamic cavitation condition to obtain modified filler powder, wherein the super-dispersion surface modifier is a high polymer comprising an oleophilic group and an anchoring group, the oleophilic group is an alkane chain or a polyester chain, the anchoring group is a hydroxyl group or a carboxyl group, the length n of the oleophilic-oil-based main carbon chain section is 19-50, and the hydrodynamic cavitation condition is as follows: the content of the solid filler in the two-phase fluid is 15-30%, the inlet pressure range of the hydrodynamic cavitation nozzle is 5-100 MPa, and the outlet pressure range is-0.5-4 MPa;
and SS3, uniformly mixing the polysiloxane and the modified heat-conducting powder filler obtained in the step SS2, and thinly passing the mixture for a plurality of times on a three-roll grinding machine to prepare the uniformly flowing heat-conducting silicone grease composition.
2. The preparation method according to claim 1, wherein in step SS1, the filler powder is placed in a vacuum drying oven, vacuumized, heated at 50-300 ℃ for 0.5-10 hours, and dried to obtain the dry powder.
3. The preparation method according to claim 1, wherein in the step SS2, the treatment time of hydrodynamic cavitation is 5-120 min, the cavitation treatment temperature is 10-70 ℃, and after the reaction is completed, the powder is dried at 90-200 ℃ for 0.5-4 hours to obtain the modified powder.
4. The method of claim 1, wherein in step SS2, the hydrodynamic cavitation nozzle is a venturi tube.
5. The preparation method of claim 1, wherein in the step SS2, the number of hydrodynamic cavitation cycles is 2-8.
6. The preparation method according to claim 1, wherein in step SS3, the polyorganosiloxane and the modified heat-conducting powder filler are uniformly mixed and passed through a three-roll mill for 3-20 passes.
7. The preparation method according to claim 1, wherein in step SS3, when the polyorganosiloxane and the modified heat-conducting powder filler are mixed, the mass ratio of the polyorganosiloxane is 3% -60%, and the rest is the modified heat-conducting powder filler.
8. The method according to claim 1, wherein in step SS3, other additives are added to the mixture of the polyorganosiloxane and the modified thermally conductive powder filler.
9. The preparation method according to claim 8, wherein in step SS3, when the polyorganosiloxane, the modified heat-conducting powder filler and the other additives are mixed, the mass ratio of the polyorganosiloxane is 3-60%, the mass ratio of the other additives is 0-10%, and the balance is the modified heat-conducting powder filler.
10. The heat-conducting silicone grease composition obtained by the preparation method of any one of claims 1 to 9, characterized in that the heat-conducting silicone grease composition is prepared from at least the following raw materials in parts by mass:
(A) 3 to 60 percent of polyorganosiloxane,
(B) 10 to 97 percent of heat-conducting filler,
(C) 0.1 to 10 percent of ultra-dispersed surface modifier;
the sum of all the components is 100 percent.
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| CN102134474A (en) * | 2010-12-29 | 2011-07-27 | 深圳市优宝惠新材料科技有限公司 | Thermal grease composition |
| CN104479636A (en) * | 2014-11-25 | 2015-04-01 | 冯智勇 | Novel heat transfer fluid material containing nanoscale pure-copper microparticles |
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| Publication number | Priority date | Publication date | Assignee | Title |
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| US20070031684A1 (en) * | 2005-08-03 | 2007-02-08 | Anderson Jeffrey T | Thermally conductive grease |
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| Publication number | Priority date | Publication date | Assignee | Title |
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| CN102134474A (en) * | 2010-12-29 | 2011-07-27 | 深圳市优宝惠新材料科技有限公司 | Thermal grease composition |
| CN104479636A (en) * | 2014-11-25 | 2015-04-01 | 冯智勇 | Novel heat transfer fluid material containing nanoscale pure-copper microparticles |
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