Highly thermally conductive single-component gel and method for producing same

Abstract

The application belongs to the field of thermal interface materials, in particular to the field of C08L83 / 07, and more particularly to a high-thermal-conductivity single-component gel and a preparation method thereof. The preparation raw materials of the high-thermal-conductivity single-component gel include 100-300 parts of modified compound fillers, 1-10 parts of vinyl silicone oil, 0.1-1 part of a crosslinking agent, 0.1-1 part of an inhibitor and 0.1-1 part of a catalyst, wherein the modified compound fillers include fillers and modifiers, and the fillers include cubic boron nitride and ceramic fillers. The high-thermal-conductivity single-component gel containing cubic boron nitride has excellent thermal conductivity, the thermal conductivity coefficient reaches more than 15 W / mK, the extrusion rate is high, the gel has good gap-filling effect, the gel is soft and easy to disassemble after solidification, has good repeatability, and is particularly suitable for use as a heat dissipation material of electronic equipment.

Description

TECHNICAL FIELD

[0001] The present application belongs to the field of thermal interface materials, especially relates to the field of C08L83 / 07, and more particularly relates to a high-thermal-conductivity single-component gel and a preparation method thereof. BACKGROUND

[0002] With the development of modern electronic technology, electronic devices begin to develop towards high power consumption, miniaturization and integration, and their energy density is greatly improved, which brings more and more serious heat dissipation problems. The heat output rate increases rapidly, and the failure of thermal management may cause the destruction of the circuit board components, which not only affects the normal work of the electronic equipment, but also may cause certain safety hazards. Therefore, the thermal management of electronic devices is particularly important. The surfaces of electronic devices and heat dissipation modules are not absolutely smooth, and have a certain roughness. Air with low thermal conductivity will fill the gap between the surfaces of electronic devices and heat dissipation modules, which finally leads to unsatisfactory heat dissipation effect. Thermal interface material is the best choice to help solve the poor heat dissipation problem of electronic equipment. At present, the industry mainly improves the surface heat dissipation efficiency of electronic equipment by placing thermal interface material between electronic devices and heat dissipation devices. Compared with other thermal interface materials, thermal conductive gel has the advantages of high thermal conductivity, low stress and repeatability, and is a research hotspot in the field of thermal interface materials. Although there has been some research progress in thermal conductive gel, the heat dissipation capacity still needs to be further strengthened. Cubic boron nitride (c-BN) as a high-thermal-conductivity material shows great application potential in the field of electronic device thermal management. The thermal conductivity of c-BN single crystal can reach 1300 W / (m·K) in theory, and its thermal conductivity is only second to that of diamond, but its thermal stability is much higher than that of diamond. c-BN has high hardness and chemical inertness, but its application in mixing with resin matrix is unsatisfactory. Therefore, the research on the filling of c-BN in thermal conductive gel is one of the optimal methods to change the thermal conductivity; adding a certain amount of c-BN in the thermal conductive gel can greatly improve the thermal conductivity of electronic equipment, which is the best solution to the existing problems.

[0003] The prior art patent CN111410459B discloses a two-component heat-conducting gel for 5G communication, which is prepared from A component and B component. The A component comprises silicone resin, filler, styrene-based siloxane, etc. The B component comprises silicone resin, filler, catalyst, night scene type epoxy resin modified silicone, etc. The two-component heat-conducting gel has good heat-conducting performance and can be reused, but may have bubbles, overflow and oiling, affecting the use effect of the product. The prior art patent CN112322042A discloses a high-heat-conducting single-component heat-conducting gel, which is prepared from heat-conducting powder, silicone oil, silane coupling agent and platinum gold mixture. The heat-conducting powder comprises hard acid ester modified aluminum oxide, aluminum hydroxide and zinc oxide, and the heat-conducting performance can reach above 6.5 W / M·K, but the heat-conducting coefficient is relatively low. Therefore, there is an urgent need for a high-heat-conducting gel with high heat-conducting coefficient and excellent heat-conducting performance. SUMMARY

[0004] To solve the above problems, the first aspect of the present application provides a high-heat-conducting single-component gel, which is prepared from at least the following raw materials in terms of mass percentage: 100-300 parts of modified compound filler, 1-10 parts of vinyl silicone oil, 0.1-1 part of crosslinking agent, 0.1-1 part of inhibitor and 0.1-1 part of catalyst.

[0005] Modified compounded filler

[0006] Preferably, the modified compound filler is prepared from filler and modifier.

[0007] Further preferably, the mass ratio of the filler to the modifier is 100:(0.5-1). As an implementable case, the mass ratio of the filler to the modifier can comprise 100:0.5, 100:0.8 or 100:1.

[0008] Further preferably, the modifier comprises one or more of octyltrimethoxysilane, dodecyltrimethoxysilane, n-octyltriethoxysilane, vinyltrimethoxysilane, trimethoxysilyl polydimethylsiloxane, hydroxypolydimethylsiloxane and glycol polydimethylsiloxane.

[0009] Further preferably, the modifier comprises dodecyltrimethoxysilane and trimethoxysilyl polydimethylsiloxane, and the mass ratio of dodecyltrimethoxysilane to trimethoxysilyl polydimethylsiloxane is 100:(0.05-1). As an implementable case, the mass ratio of dodecyltrimethoxysilane to trimethoxysilyl polydimethylsiloxane can comprise 100:0.05, 100:0.1, 100:0.2, 100:0.5 or 100:1.

[0010] Further preferably, the fillers include ceramic fillers and cubic boron nitride.

[0011] Further preferably, the ceramic fillers include one or a mixture of several of spherical alumina, single crystal alumina, zinc oxide, magnesium oxide, magnesium hydroxide, aluminum hydroxide, aluminum nitride, and hexagonal boron nitride.

[0012] Further preferably, the ceramic fillers include at least spherical alumina, single crystal alumina, zinc oxide, and aluminum nitride.

[0013] Further preferably, the mass ratio of the spherical alumina, single crystal alumina, zinc oxide, aluminum nitride, and cubic boron nitride is (5-15):(5-15):(5-10):(15-30):(40-60); as an implementable case, the mass ratio of the spherical alumina, single crystal alumina, zinc oxide, aluminum nitride, and cubic boron nitride can be 10:10:6.5:20:50.

[0014] Further preferably, the particle size of the spherical alumina is 1-120 μm; the particle size of the single crystal alumina is 0.3-5 μm; the particle size of the zinc oxide is 0.5-5 μm; the particle size of the aluminum nitride is 2-150 μm; the particle size of the cubic boron nitride is 5-200 μm; as an implementable case, the particle size of the spherical alumina is 1-40 μm; the particle size of the single crystal alumina is 0.3-5 μm; the particle size of the zinc oxide is 0.5-5 μm; the particle size of the aluminum nitride is 2-80 μm; the particle size of the cubic boron nitride is 80-200 μm.

[0015] Further preferably, the preparation method of the modified compound filler includes at least the following steps:

[0016] S1, after mixing the fillers uniformly, pour into the modification equipment for premixing, close the modification equipment cover, make it airtight, then stir at a stirring speed of 10-100 rpm for 1-60 min, after stirring, open the modification equipment cover, clean the cavity wall;

[0017] S2, add the modifier again, close the modification equipment cover, stir at a stirring speed of 30-150 rpm for 1-60 min, after stirring, open the modification equipment cover, clean the cavity wall;

[0018] S3, close the equipment cover again, stir at a speed of 80-300 rpm for 1-60 min, after stirring, take out the modified fillers, bake in an oven at 50-170℃ for 0.1-24 h, after baking, take out, wait for it to cool to room temperature, then the modified compound filler can be obtained.

[0019] As an implementable case, the rotating speed in the S1 step can include 10 rpm, 20 rpm, 30 rpm, 40 rpm, 50 rpm, 60 rpm, 70 rpm, 80 rpm, 90 rpm or 100 rpm; the stirring time can include 1 min, 5 min, 10 min, 20 min, 30 min, 40 min, 50 min or 60 min; further preferably, the stirring speed is 30 rpm and the stirring time is 5 min.

[0020] As an implementable case, the rotating speed in the S2 step can include 30 rpm, 40 rpm, 50 rpm, 60 rpm, 70 rpm, 80 rpm, 100 rpm, 120 rpm, 130 rpm or 150 rpm; the stirring time can include 1 min, 5 min, 10 min, 20 min, 30 min, 40 min, 50 min or 60 min; further preferably, the stirring speed is 80 rpm and the stirring time is 20 min.

[0021] As an implementable case, the rotating speed in the S3 step can include 80 rpm, 120 rpm, 150 rpm, 180 rpm, 200 rpm, 240 rpm, 270 rpm or 300 rpm; the stirring time can include 1 min, 5 min, 10 min, 20 min, 30 min, 40 min, 50 min or 60 min; the oven temperature can include 50℃, 70℃, 90℃, 100℃, 110℃, 130℃, 150℃ or 170℃; the baking time can include 0.1h, 1h, 3h, 6h, 9h, 12h, 15h, 20h or 24h; the cooling temperature can include 20℃, 22℃, 25℃, 28℃ or 30℃; further preferably, the stirring speed is 30 rpm, the stirring time is 5 min, the baking temperature is 130℃, the baking time is 1h and the cooling temperature is 25℃.

[0022] In order to improve the thermal conductivity of the high-thermal-conductivity single-component gel, the inventor adds cubic boron nitride into the gel. The cubic boron nitride has a unique stable cubic crystal structure. The nitrogen atom and the boron atom will form SP 3The cubic boron nitride is hybridized in a manner that is very high in thermal stability, and the heat resistance temperature is as high as 1400-1500 DEG C, and the cubic boron nitride is converted into hexagonal crystal at above 1370 DEG C to start softening, in addition, the cubic boron nitride also has excellent thermal conductivity, and the thermal conductivity coefficient is 79.54 w / m.k, and the thermal conductivity coefficient of the cubic boron nitride gradually increases with the increase of temperature, and the heat dissipation performance of the gel can be obviously improved, but the monocrystalline cubic boron nitride grain is small in size, anisotropic, and has cleavage surface which is easy to split, and is large in brittleness, and is extremely easy to dissociate and break, and the present inventors find in experiments that when the ceramic filler of a specific component is compounded with the cubic boron nitride, the defect of brittleness can be obviously modified, wherein the ceramic filler includes spherical alumina, monocrystalline alumina, zinc oxide, aluminum nitride, and the mass ratio of the spherical alumina, the monocrystalline alumina, the zinc oxide, the aluminum nitride and the cubic boron nitride is (5-15):(5-15):(5-10):(15-30):(40-60), so that the overall density and toughness of the modified compounded filler can be improved, the gap between the processing surfaces can be filled, the uniform contact and the high heat transfer efficiency can be ensured, and the heat dissipation performance of the gel can be improved, but the above-mentioned filler is poor in compatibility with other chemical substances due to the relatively excellent chemical stability, and the present inventors find in actual experiments that when the modifier is the compound of dodecyl trimethoxysilane and trimethoxysilyl polydimethylsiloxane, the organic alkyl chain and the methoxy group in the molecule can chemically react with the surface of the filler to form a dense siloxane polymer film layer, so that the stability of the gel can be improved, and the thermal conductivity coefficient of the gel can be improved. After the filler is modified, the filler can better generate strong intermolecular forces with the vinyl silicone oil, the crosslinking agent and the like, so that the toughness and the gel output of the gel can be improved.

[0023] Vinyl silicone oil

[0024] Preferably, the vinyl content of the vinyl silicone oil is 1-1.8%, and the viscosity is 40-300 mm 2 / s; as an implementable case, the vinyl content of the vinyl silicone oil can be 1.06%, and the viscosity can be 100 mm 2 / s, which can be purchased from Guangdong Chenxi New Material Technology Co., Ltd., and the model is cx-352-100cSt.

[0025] In the present application, the vinyl silicone oil with specific vinyl content and viscosity can be mixed with the hydrogen-containing silicone oil at the end or at the side as the raw material for preparing the gel to improve the performance of the gel, wherein the single-end vinyl silicone oil and the hydrogen-containing silicone oil at the end can produce long molecular chains, which is conducive to the mutual entanglement between the molecular weights, thereby increasing the toughness of the silicone gel; the single-end vinyl silicone oil and the hydrogen-containing silicone oil at the side can cross-link the system to improve the strength of the silicone gel; since the viscosity and hydrogen content of the hydrogen-containing silicone oil at the end and the hydrogen-containing silicone oil at the side are low, the gel cannot be completely cross-linked, thereby ensuring the good adhesion of the gel.

[0026] Crosslinker

[0027] Preferably, the cross-linking agent is a mixture composed of one or more of the hydrogen-containing silicone oil at the end, the hydrogen-containing silicone oil at the side or the hydrogen-containing silicone oil at the end and the side.

[0028] Further preferably, the cross-linking agent is the hydrogen-containing silicone oil at the end and the hydrogen-containing silicone oil at the side.

[0029] Further preferably, the mass ratio of the hydrogen-containing silicone oil at the end to the hydrogen-containing silicone oil at the side is (1-2):(3-5); as an implementable case, the mass ratio of the hydrogen-containing silicone oil at the end to the hydrogen-containing silicone oil at the side can include one of 1:2, 2:3, 2:5 and 1:3.

[0030] Further preferably, the hydrogen content of the hydrogen-containing silicone oil at the end is 0.01-0.1wt%, and the viscosity is 10-200mm 2 / s; as an implementable case, the hydrogen content of the hydrogen-containing silicone oil at the end is 0.06-0.08wt%, and the viscosity is 30-50mm 2 / s; the model can be RH-DH07 of Ningbo Runhe High-tech Material Science and Technology Co., Ltd.

[0031] Further preferably, the hydrogen content of the hydrogen-containing silicone oil at the side is 0.7-1.0wt%, and the viscosity is 60-120mm 2 / s; as an implementable case, the hydrogen content of the hydrogen-containing silicone oil at the side is 0.75-0.79wt%, and the viscosity is 70-110mm 2 / s; the model can be RH-H502 of Ningbo Runhe High-tech Material Science and Technology Co., Ltd.

[0032] The heat-conducting gel prepared in the present application has a suitable network cross-linking structure formed between the end vinyl silicone oil with different chain lengths and the hydrogen-containing silicone oil at the end and the side, wherein the hydrogen content of the hydrogen-containing silicone oil at the end is 0.01-0.1wt%, and the viscosity is 10-200mm 2 / s; the hydrogen content of the hydrogen-containing silicone oil at the side is 0.7-1.0wt%, and the viscosity is 60-120mm 2The stability of the gel system can be improved, in addition, the dodecyl trimethoxysilane is introduced as the trimethoxysilyl polydimethylsiloxane modified modified composite filler containing cubic boron nitride to improve the strength of the gel, the modified composite filler of the system is uniformly and stably wrapped in the reticular crosslinked structure system, so that the stability of the heat-conducting gel is high, and the gel extrusion rate can be improved.

[0033] Inhibitor

[0034] As an implementable case, the inhibitor can include ethynylcyclohexanol.

[0035] Catalyst

[0036] Preferably, the catalyst is a platinum gold catalyst.

[0037] Further preferably, the platinum gold catalyst is a microcapsule type platinum catalyst, and the platinum content is 1000-10000 ppm; as an implementable case, the capsule type platinum catalyst has a platinum content of 3000 ppm.

[0038] The second aspect of the application provides a preparation method of a high-thermal-conductivity single-component gel, at least comprising the following steps:

[0039] L1, first open the mold temperature machine, and keep the temperature in the kneader container at 15-20 DEG C by using the cold end;

[0040] L2, the vinyl silicone oil is added into the kneader container, and then the modified composite filler is added into the container, and stirred at a speed of 20-80 rpm for 1-20 min, and the vacuum is kept on during the stirring;

[0041] L3, after the stirring is finished, the crosslinking agent, the inhibitor and the catalyst are added, and stirred at a speed of 5-50 rpm for 5-60 min, and the vacuum is kept on during the stirring, and after the stirring is finished, the mixture in the kneader is taken out, and a high-thermal-conductivity single-component gel containing cubic boron nitride is obtained.

[0042] As an implementable case, the temperature in the L1 step can include 15℃, 16℃, 17℃, 18℃, 19℃ or 20℃; the rotating speed in the L2 step can include 20rpm, 30rpm, 40rpm, 50rpm, 60rpm, 70rpm or 80rpm, and the stirring time can include 1min, 5min, 10min, 15min or 20min; the rotating speed in the L3 step can include 5rpm, 10rpm, 20rpm, 25rpm, 30rpm, 40rpm or 50rpm, and the stirring time can include 5min, 15min, 30min, 45min or 60min; further preferably, the temperature in the L1 step is 20℃; the rotating speed in the L2 step is 30rpm, and the stirring time is 10min; the rotating speed in the L3 step is 30rpm, and the stirring time is 30min.

[0043] Advantages

[0044] (1) In the present application, the preparation raw materials of the gel include modified compound filler 100-300 parts, vinyl silicone oil 1-10 parts, crosslinking agent 0.1-1 part, inhibitor 0.1-1 part, and catalyst 0.1-1 part. The prepared gel has excellent heat conduction effect, the heat conduction coefficient reaches more than 15W / mK, the extrusion rate is high, the gel has good gap filling effect, and after curing, it is soft and easy to disassemble, has good repeatability, and is especially suitable for use as a heat dissipation material of electronic equipment.

[0045] (2) In the present application, the filler includes ceramic filler and cubic boron nitride, wherein the ceramic filler at least includes spherical alumina, single crystal alumina, zinc oxide and aluminum nitride; the mass ratio of the spherical alumina, single crystal alumina, zinc oxide, aluminum nitride and cubic boron nitride is (5-15):(5-15):(5-10):(15-30):(40-60). The modified compound filler not only can improve the overall density and toughness, but also can ensure uniform contact and high heat transfer efficiency by filling the gap between the processing surfaces, thereby improving the heat conduction and heat dissipation performance of the gel.

[0046] (3) In the present application, the dimethyldimethylsiloxane compound is modified as a filler by using dodecyltrimethoxysilane as a trimethoxysilyl group, which can not only enhance the stability of the gel, but also enhance the heat conductivity of the gel.

[0047] (4) In the present application, the single-end vinyl silicone oil and the end hydrogen-containing silicone oil and the side hydrogen-containing silicone oil with specific vinyl content and viscosity are mixed as the preparation raw materials of the gel, which can increase the toughness and strength of the gel, and also can ensure good adhesion of the gel.

[0048] (V) In the present application, the suitable network crosslinking structure formed between the end-vinyl silicone oil with different chain length and the side hydrogen-containing silicone oil can improve the stability of the gel system, and can also act together with the modified compound filler to improve the strength and extrusion rate of the gel. DETAILED DESCRIPTION

[0049] Example 1

[0050] The first aspect of the present embodiment provides a high-thermal-conductivity single-component gel, which is prepared from the following raw materials in terms of mass fraction: modified compound filler 150 parts, vinyl silicone oil 4 parts, crosslinking agent 0.2 parts, inhibitor 0.2 parts, and catalyst 0.05 parts.

[0051] The modified compound filler is prepared from a filler and a modifier, and the mass ratio of the filler to the modifier is 100:1; wherein the modifier is dodecyltrimethoxysilane (CAS: 3069-21-4) and trimethoxysilyl polydimethylsiloxane, and the mass ratio of the dodecyltrimethoxysilane to the trimethoxysilyl polydimethylsiloxane is 100:1; the filler is ceramic filler and cubic boron nitride; the ceramic filler is spherical alumina, single-crystal alumina, zinc oxide, and aluminum nitride; the mass ratio of the spherical alumina, the single-crystal alumina, the zinc oxide, the aluminum nitride, and the cubic boron nitride is 10:10:6.5:20:50; the particle size of the spherical alumina is 1-40 μm; the particle size of the single-crystal alumina is 0.3-5 μm; the particle size of the zinc oxide is 0.5-5 μm; the particle size of the aluminum nitride is 2-80 μm; and the particle size of the cubic boron nitride is 80-200 μm.

[0052] The preparation method of the modified compound filler is as follows:

[0053] S1, after the filler is uniformly mixed, it is poured into a modification device for premixing, the modification device is closed and sealed, and then stirred at a speed of 30 rpm for 5 min; after the stirring is completed, the modification device is opened, and the cavity wall is cleaned;

[0054] S2, the modifier is added again, the modification device is closed and sealed, and then stirred at a speed of 80 rpm for 10 min; after the stirring is completed, the modification device is opened, and the cavity wall is cleaned;

[0055] S3, the device is closed and sealed again, and then stirred at a speed of 120 rpm for 20 min; after the stirring is completed, the modified filler is taken out, placed in an oven at 130°C for baking for 1 h, taken out after the baking, and then cooled to 25°C to obtain the modified compound filler.

[0056] The vinyl silicone oil has a vinyl content of 1.06% and a viscosity of 100 mm 2 / s, purchased from Guangdong Chenxi New Material Technology Co., Ltd., model number cx-352-100cSt.

[0057] The cross-linking agent is a terminal hydrogen-containing silicone oil and a side hydrogen-containing silicone oil, the mass ratio of the terminal hydrogen-containing silicone oil and the side hydrogen-containing silicone oil is 2:3, the hydrogen content of the terminal hydrogen-containing silicone oil is 0.06-0.08wt%, and the viscosity is 30-50mm 2 / s, model number RH-DH07 of Ningbo Runhe High-tech Material Technology Co., Ltd.; the hydrogen content of the side hydrogen-containing silicone oil is 0.75-0.79wt%, and the viscosity is 70-110mm 2 / s; model number RH-H502 of Ningbo Runhe High-tech Material Technology Co., Ltd.

[0058] The inhibitor is ethynylcyclohexanol (CAS number: 78-27-3).

[0059] The catalyst is a platinum gold catalyst, and the platinum gold catalyst is a microcapsule type platinum catalyst; the content of platinum in the microcapsule type platinum catalyst is 3000ppm.

[0060] The second aspect of the embodiment provides a preparation method of the high-thermal-conductivity single-component gel, in particular to the following steps:

[0061] L1, first open the mold temperature machine, and keep the temperature in the kneader container at 20℃ by using the cold end;

[0062] L2, add the vinyl silicone oil into the kneader container, and then add the modified compound filler into the container, stir for 10min at a speed of 30rpm, and keep the vacuum open during the stirring;

[0063] L3, after the stirring, add the cross-linking agent, the inhibitor and the catalyst, stir for 30min at a speed of 30rpm, keep the vacuum open during the stirring, and then take out the mixture in the kneader, to obtain the high-thermal-conductivity single-component gel containing cubic boron nitride.

[0064] Example 2

[0065] The first aspect of the embodiment provides a high-thermal-conductivity single-component gel, and the preparation raw materials are as follows in terms of mass fraction: modified compound filler 150 parts, vinyl silicone oil 4 parts, cross-linking agent 0.35 parts, inhibitor 0.2 parts, and catalyst 0.05 parts.

[0066] The preparation raw material of the modified compound filler is filler and modifier, and the mass ratio of the filler and the modifier is 100:1; wherein the modifier is dodecyl trimethoxysilane (CAS: 3069-21-4) and trimethoxysilyl polydimethylsiloxane, and the mass ratio of the dodecyl trimethoxysilane and the trimethoxysilyl polydimethylsiloxane is 100:1; the filler includes ceramic filler and cubic boron nitride; the ceramic filler includes spherical alumina, single crystal alumina, zinc oxide and aluminum nitride; the mass ratio of the spherical alumina, the single crystal alumina, the zinc oxide, the aluminum nitride and the cubic boron nitride is 10:10:6.5:20:50, the particle size of the spherical alumina is 1-40 μm, the particle size of the single crystal alumina is 0.3-5 μm, the particle size of the zinc oxide is 0.5-5 μm, the particle size of the aluminum nitride is 2-80 μm, and the particle size of the cubic boron nitride is 80-200 μm.

[0067] The preparation method of the modified compound filler is as follows:

[0068] S1, after the filler is uniformly mixed, it is poured into a modification device for premixing, the modification device cover is closed to make it airtight, then stirring is carried out at a speed of 30 rpm for 5 min, after the stirring is completed, the modification device cover is opened, and the cavity wall is cleaned;

[0069] S2, the modifier is added again, the modification device cover is closed, and stirring is carried out at a speed of 80 rpm for 10 min, after the stirring is completed, the modification device cover is opened, and the cavity wall is cleaned;

[0070] S3, the device cover is closed again, and stirring is carried out at a speed of 120 rpm for 20 min, after the stirring is completed, the modified filler is taken out, and is baked in an oven at 130℃ for 1 h, after the baking, it is taken out, and is cooled to 25℃, then the modified compound filler is obtained.

[0071] The vinyl content of the vinyl silicone oil is 1.06%, and the viscosity is 100 mm 2 / s, which is purchased from Guangdong Chenxi New Material Technology Co., Ltd., and the model is cx-352-100cSt.

[0072] The crosslinking agent is end hydrogen-containing silicone oil and side hydrogen-containing silicone oil, and the mass ratio of the end hydrogen-containing silicone oil and the side hydrogen-containing silicone oil is 2:3, the hydrogen content of the end hydrogen-containing silicone oil is 0.06-0.08 wt%, and the viscosity is 30-50 mm 2 / s; the model is RH-DH07 of Ningbo Runhe High-tech Material Technology Co., Ltd.; the hydrogen content of the side hydrogen-containing silicone oil is 0.75-0.79 wt%, and the viscosity is 70-110 mm 2 / s; the model is RH-H502 of Ningbo Runhe High-tech Material Technology Co., Ltd.

[0073] The inhibitor is ethynylcyclohexanol (CAS No. 78-27-3).

[0074] The catalyst is a platinum gold catalyst, and the platinum gold catalyst is a microcapsule type platinum catalyst; the content of platinum in the microcapsule type platinum catalyst is 3000 ppm.

[0075] The second aspect of the embodiment provides a preparation method of the high-thermal-conductivity single-component gel, in particular to the following steps:

[0076] L1, first open the mold temperature machine, and keep the temperature in the kneader container at 20℃ by using the cold end;

[0077] L2, add the vinyl silicone oil into the kneader container, and then add the modified compound filler into the container, stir for 10 minutes at a speed of 30 rpm, and keep the vacuum open during the stirring;

[0078] L3, after the stirring, add the crosslinking agent, the inhibitor and the catalyst, stir for 30 minutes at a speed of 30 rpm, keep the vacuum open during the stirring, and then take out the mixture in the kneader, thereby obtaining the high-thermal-conductivity single-component gel containing cubic boron nitride.

[0079] Example 3

[0080] The first aspect of the embodiment provides a high-thermal-conductivity single-component gel, and the preparation raw materials are as follows in terms of mass fraction: modified compound filler 170 parts, vinyl silicone oil 4 parts, crosslinking agent 0.2 parts, inhibitor 0.2 parts and catalyst 0.05 parts.

[0081] The preparation raw materials of the modified compound filler are filler and modifier, and the mass ratio of the filler and the modifier is 100:1; wherein the modifier is dodecyltrimethoxysilane (CAS: 3069-21-4) and trimethoxysilyl polydimethylsiloxane, and the mass ratio of the dodecyltrimethoxysilane and the trimethoxysilyl polydimethylsiloxane is 100:1; the filler includes ceramic filler and cubic boron nitride; the ceramic filler is spherical alumina, single-crystal alumina, zinc oxide and aluminum nitride; the mass ratio of the spherical alumina, the single-crystal alumina, the zinc oxide, the aluminum nitride and the cubic boron nitride is 10:10:6.5:20:50, the particle size of the spherical alumina is 1-40 μm, the particle size of the single-crystal alumina is 0.3-5 μm, the particle size of the zinc oxide is 0.5-5 μm, the particle size of the aluminum nitride is 2-80 μm, and the particle size of the cubic boron nitride is 80-200 μm.

[0082] The preparation method of the modified compound filler is as follows:

[0083] S1, after the filler is mixed uniformly, pour into the modified equipment premix, close the modified equipment cover, make it airtight, then stir at 30 rpm for 5 min, open the modified equipment cover after stirring, clean the cavity wall;

[0084] S2, add modifier again, close the modified equipment cover, stir at 80 rpm for 10 min, open the modified equipment cover after stirring, clean the cavity wall;

[0085] S3, close the equipment cover again, stir at 120 rpm for 20 min, take out the modified filler after stirring, bake in the oven at 130 DEG C for 1 h, take out after baking, wait for it to cool to 25 DEG C, and the modified compound filler can be obtained.

[0086] The vinyl content of the vinyl silicone oil is 1.06%, and the viscosity is 100 mm 2 / s, purchased from Guangdong Chenxi New Material Technology Co., Ltd., model cx-352-100cSt.

[0087] The crosslinking agent is end hydrogen-containing silicone oil and side hydrogen-containing silicone oil, and the mass ratio of end hydrogen-containing silicone oil and side hydrogen-containing silicone oil is 2:3, the hydrogen content of end hydrogen-containing silicone oil is 0.06-0.08wt%, and the viscosity is 30-50 mm 2 / s; model is RH-DH07 of Ningbo Runhe High-tech Material Technology Co., Ltd.; the hydrogen content of side hydrogen-containing silicone oil is 0.75-0.79wt%, and the viscosity is 70-110 mm 2 / s; model is RH-H502 of Ningbo Runhe High-tech Material Technology Co., Ltd.

[0088] The inhibitor is ethynylcyclohexanol (CAS number: 78-27-3).

[0089] The catalyst is platinum gold catalyst, and the platinum gold catalyst is microcapsule type platinum catalyst; the platinum content in the microcapsule type platinum catalyst is 3000 ppm.

[0090] The second aspect of the embodiment provides a preparation method of high-thermal-conductivity single-component gel, specifically:

[0091] L1, first open the mold temperature machine, and keep the temperature in the kneader container at 20 DEG C all the time with the cold end;

[0092] L2, add vinyl silicone oil into the kneader container, then add the modified compound filler into the container, stir at 30 rpm for 10 min, and the vacuum is turned on all the time during stirring;

[0093] L3, after the end of stirring, crosslinking agent, inhibitor and catalyst were added, stirring at 30 rpm for 30 min, the vacuum was opened during stirring, after the end of stirring, the mixture in the kneader was taken out, and the high-thermal-conductivity single-component gel containing cubic boron nitride was obtained.

[0094] Comparative Example 1

[0095] The specific implementation of the comparative example is the same as that of example 1, except that the modified compound filler is only premixed without adding a modifier.

[0096] Comparative Example 2

[0097] The specific implementation of the comparative example is the same as that of example 1, except that the preparation method of the high-thermal-conductivity single-component gel containing cubic boron nitride does not include the L1 step, and the room temperature is 25℃.

[0098] Comparative Example 3

[0099] The specific implementation of the comparative example is the same as that of example 1, except that the catalyst is 0.2 parts.

[0100] Performance evaluation

[0101] Test one, thermal conductivity: measured according to standard ASTM D 5470-17 using Taiwan Ruiling LW-9389 interface material thermal resistance and thermal conductivity measuring device (at 25℃ environment)

[0102] Test two, curing hardness: measured according to standard ASTM D2240 using shore 00 hardness tester (at 25℃)

[0103] Test three, extrusion rate: measured according to standard ASTM D2452-2015

[0104] Test four, curing time: measured according to standard GB / T 7123.4-2015

[0105] Test object: the high-thermal-conductivity single-component gel prepared by examples 1-3 and comparative examples 1-3, and the above test results are recorded in table 1

[0106] Table 1

[0107]

Claims

1. A method for preparing a high thermal conductive single component gel, characterized in that, At least comprising the following steps: L1, first open the mold temperature machine, with the cold end to keep the temperature of the kneader container at 15-20℃; L2, add vinyl silicone oil into the kneader container, then add the modified compound filler into the container, stir at 20-80rpm for 1-20min, and the vacuum is always on during stirring; L3, after stirring, add crosslinking agent, inhibitor and catalyst, stir at 5-50rpm for 5-60min, and the vacuum is always on during stirring, then take out the mixture in the kneader, and the high thermal conductivity single-component gel is obtained; The preparation raw materials of the high thermal conductivity single-component gel at least comprise modified compound filler 100-300 parts, vinyl silicone oil 1-10 parts, crosslinking agent 0.1-1 part, inhibitor 0.1-1 part and catalyst 0.05 part by mass fraction; The preparation raw materials of the modified compound filler comprise filler and modifier; the filler comprises ceramic filler and cubic boron nitride; the ceramic filler at least comprises spherical alumina, single crystal alumina, zinc oxide and aluminum nitride; the mass ratio of the spherical alumina, single crystal alumina, zinc oxide and aluminum nitride and cubic boron nitride is (5-15):(5-15):(5-10):(15-30):(40-60); the particle size of the spherical alumina is 1-40μm; the particle size of the single crystal alumina is 0.3-5μm; the particle size of the zinc oxide is 0.5-5μm; the particle size of the aluminum nitride is 2-80μm; and the particle size of the cubic boron nitride is 80-200μm; The modifier comprises dodecyltrimethoxysilane and trimethoxysilyl polydimethylsiloxane, and the mass ratio of the dodecyltrimethoxysilane and trimethoxysilyl polydimethylsiloxane is 100:(0.05-1); The preparation method of the modified compound filler at least comprises the following steps: S1, after mixing the filler uniformly, pour it into the modification equipment for premixing, close the modification equipment cover to make it airtight, then stir at a stirring speed of 10-100rpm for 1-60min, open the modification equipment cover after stirring, and clean the cavity wall; S2, then add the modifier, close the modification equipment cover, and stir at a stirring speed of 30-150rpm for 1-60min, open the modification equipment cover after stirring, and clean the cavity wall; S3, close the equipment cover again, stir at a speed of 80-300rpm for 1-60min, take out the modified filler after stirring, bake it in an oven at 50-170℃ for 0.1-24h, take it out after baking, and cool it to room temperature, and the modified compound filler is obtained; The vinyl silicone oil has a vinyl content of 1.06% and a viscosity of 100 mm 2 / s, model cx-352-100 cSt The crosslinking agent is a terminal hydrogen-containing silicone oil and a side hydrogen-containing silicone oil, the mass ratio of the terminal hydrogen-containing silicone oil and the side hydrogen-containing silicone oil is (1-2):(3-5), the hydrogen content of the terminal hydrogen-containing silicone oil is 0.06-0.08wt%, and the viscosity is 30-50mm 2 / s, the hydrogen content of the side hydrogen-containing silicone oil is 0.75-0.79wt%, and the viscosity is 70-110mm 2 / s; The inhibitor is acetylene cyclohexanol; The catalyst is platinum gold catalyst.

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