Subliquid thermal interface material as well as preparation method and application thereof

Abstract

The invention provides an under-liquid thermal interface material as well as a preparation method and application thereof. The preparation raw materials of the under-liquid thermal interface material comprise the following components: (A) side chain hydrogen-based polydimethylsiloxane; (B) double-end vinyl polydimethylsiloxane; (C) an acrylate monomer containing an epoxy group, and / or a silane coupling agent containing a carbon-carbon double bond and a siloxymethyl group; and (D) a thermally conductive filler. According to the thermal interface material provided by the invention, side chain hydrogen-based polydimethylsiloxane and double-end vinyl polydimethylsiloxane form a basic polymer network through a hydrosilylation reaction, and an acrylate monomer containing an epoxy group and / or a silane coupling agent containing a carbon-carbon double bond and siloxymethyl and a heat-conducting filler are introduced; therefore, the thermal interface material has high adhesion and high thermal conductivity when being applied to the cooling liquid.

Description

Technical Field

[0001] This invention belongs to the technical field of polymer-based thermally conductive composite materials based on immersion liquid cooling, and relates to an underwater thermal interface material, its preparation method, and its application. Background Technology

[0002] With the continuous advancement and development of technologies such as cloud computing, big data, and artificial intelligence, the performance of electronic devices has been greatly improved. However, this has also brought about increasingly prominent heat dissipation problems, making the demand for efficient heat dissipation solutions urgent. The combination of thermal interface materials and immersion liquid cooling technology has become a highly anticipated solution due to its excellent heat transfer and dissipation performance. In electronic devices, submersible thermal interface materials play a crucial role in the effective dissipation of heat by constructing efficient heat conduction paths. However, improving the thermal conductivity of submersible thermal interface materials is not easy and usually requires the addition of particles with high thermal conductivity. But too many thermally conductive particles can introduce defects and stress concentration, thereby weakening the adhesion between the material and the adhered object. This is like pursuing speed while neglecting stability, leading to an imbalance in the overall performance of the material. In addition, during liquid cooling, submersible thermal interface materials face complex conditions such as huge temperature gradients, mechanical vibration, and flow erosion. These factors may induce crack formation and interface delamination, thus affecting the thermal efficiency and stability of electronic devices. Current submersible thermal interface materials often suffer from insufficient adhesive strength when dealing with these complex conditions. For example, after the thermal conductivity of some thermal interface materials is improved, their bonding strength is difficult to meet the high requirements of practical applications. Especially under long-term liquid impact and temperature changes, the bonding performance will gradually decrease, resulting in gaps between the thermal interface material and electronic components, affecting the heat dissipation effect, and thus affecting the reliability of electronic equipment.

[0003] Therefore, developing a liquid thermal interface material that has both strong adhesion and high thermal conductivity in a liquid environment has become an urgent need in this field. Summary of the Invention

[0004] To address the shortcomings of existing technologies, this invention aims to provide an underwater thermal interface material, its preparation method, and its applications, thereby solving the problems of insufficient adhesion and thermal stability of existing thermal interface materials in underwater applications. Specifically, by adjusting the ratio of hydrogen bonds to covalent bonds in the polymer network, the inherent interfacial toughness and mechanical dissipation can be balanced, thus achieving robust adhesion of the thermal interface material in a liquid environment, while simultaneously synergistically suppressing crack propagation at the interface. Through in-depth exploration of the relationship between material composition and process parameters, this invention strives to develop thermal interface materials with superior adhesion and more efficient thermal conductivity to meet the urgent heat dissipation requirements of high-performance electronic devices.

[0005] To achieve this objective, the present invention adopts the following technical solution:

[0006] In a first aspect, the present invention provides a submersible thermal interface material, wherein the raw materials for preparing the submersible thermal interface material comprise the following components:

[0007] (A) Side-chain hydrogen-based polydimethylsiloxane (PDMS-H);

[0008] (B) Double-terminated vinyl polydimethylsiloxane (PDMS-Vi);

[0009] (C) Epoxy-containing acrylate monomers, and / or silane coupling agents containing carbon-carbon double bonds and siloxane methyl groups;

[0010] (D) Thermally conductive filler.

[0011] The thermal interface material provided by this invention forms a basic polymer network by hydrosilylation reaction of side-chain hydrogen-based polydimethylsiloxane (PDMS-H) and divinyl-terminated polydimethylsiloxane (PDMS-Vi), and introduces epoxy-containing acrylate monomers and / or silane coupling agents containing carbon-carbon double bonds and siloxane methyl groups, as well as thermally conductive fillers, so that the thermal interface material has both high adhesion and high thermal conductivity when applied to coolant.

[0012] Preferably, the hydrogen content of the side-chain hydrogen-based polydimethylsiloxane is 1.15 wt.% to 1.25 wt.%, for example, 1.15 wt.%, 1.16 wt.%, 1.17 wt.%, 1.18 wt.%, 1.19 wt.%, 1.20 wt.%, 1.21 wt.%, 1.22 wt.%, 1.23 wt.%, 1.24 wt.%, 1.25 wt.%, etc.

[0013] Preferably, the vinyl content of the dual-terminated vinyl polydimethylsiloxane is 0.39 wt.% to 0.45 wt.%, for example, 0.39 wt.%, 0.40 wt.%, 0.41 wt.%, 0.42 wt.%, 0.43 wt.%, 0.44 wt.%, 0.45 wt.%, etc.

[0014] Preferably, the molar ratio of silanol groups in the side-chain hydrogen-based polydimethylsiloxane to vinyl groups in the divinyl-terminated polydimethylsiloxane is 1:(0.1–0.5), for example, 1:0.1, 1:0.2, 1:0.3, 1:0.4, 1:0.5, etc. By controlling the molar ratio of silanol groups in the side-chain hydrogen-based polydimethylsiloxane to vinyl groups in the divinyl-terminated polydimethylsiloxane within this range, the polymer matrix is ​​synthesized, providing reaction sites for subsequent modification.

[0015] Preferably, the epoxy-containing acrylate monomers include 3,4-epoxycyclohexyl methacrylate (ECHMA) and / or glycidyl methacrylate.

[0016] Preferably, the silane coupling agent containing carbon-carbon double bonds and siloxane methyl groups includes γ-methacryloyloxypropyltrimethoxysilane (γ-MPS, also known as KH-570) and / or vinyltrimethoxysilane.

[0017] Preferably, the molar ratio of the silanol group in the side-chain hydrogen-based polydimethylsiloxane to the total amount of carbon-carbon double bonds in the epoxy-containing acrylate monomer and the silane coupling agent containing carbon-carbon double bonds and siloxane methyl groups is 1:(0.5-0.9), for example 1:0.5, 1:0.6, 1:0.7, 1:0.8, 1:0.9, etc.

[0018] Preferably, the molar ratio of the carbon-carbon double bond in the epoxy-containing acrylate monomer to the carbon-carbon double bond in the silane coupling agent containing carbon-carbon double bonds and siloxane methyl groups is (0-3):(0-3), for example, 0:1, 1:0, 1:1, 1:2, 1:3, 2:1, 2:3, 3:1, 3:2, etc.

[0019] To achieve robust adhesion of thermal interface materials in a liquid environment, 3,4-epoxycyclohexylmethacrylate (ECHMA, an epoxy-containing acrylate monomer with good reactivity and adhesive properties) was selected as the hydrogen-bonding monomer, and γ-methacryloyloxypropyltrimethoxysilane (γ-MPS, a silane coupling agent containing carbon-carbon double bonds and siloxane methyl groups, which can be covalently bonded to the matrix and fillers) was selected as the covalent-bonding monomer. By adjusting the molar ratio of ECHMA and γ-MPS, the inherent interfacial toughness and mechanical dissipation are balanced, synergistically inhibiting crack propagation at the interface. ECHMA provides interfacial toughness through hydrogen bonding, while γ-MPS enhances interfacial mechanical strength through covalent bonding, forming a treated zone with significant mechanical dissipation, inhibiting crack propagation, and improving adhesion and durability. This invention is based on the principles of materials chemistry and mechanics, utilizing the synergistic effect of hydrogen bonding and covalent bonding to optimize interfacial properties. γ-MPS connects to the matrix and fillers through covalent bonding, enhancing interfacial interactions, while ECHMA provides interfacial toughness through hydrogen bonding. The functional groups introduced by chemical grafting enhance the polarity of the polymer matrix, providing a chemical basis for the uniform dispersion of fillers and interfacial interactions. The constructed thermally conductive network reduces interfacial thermal resistance and optimizes heat dissipation performance.

[0020] Preferably, the thermally conductive filler comprises spherical aluminum particles.

[0021] Preferably, the spherical aluminum particles comprise a combination of spherical aluminum particles with particle sizes of 0.5–2 μm (e.g., 0.5 μm, 0.6 μm, 0.8 μm, 1 μm, 1.2 μm, 1.4 μm, 1.6 μm, 1.8 μm, 2 μm, etc.), 8–12 μm (e.g., 8 μm, 9 μm, 10 μm, 11 μm, 12 μm, etc.), 16–24 μm (e.g., 16 μm, 17 μm, 18 μm, 19 μm, 20 μm, 21 μm, 22 μm, 23 μm, 24 μm, etc.), and 40–60 μm (e.g., 40 μm, 42 μm, 44 μm, 46 μm, 48 μm, 50 μm, 52 μm, 54 μm, 56 μm, 58 μm, 60 μm, etc.).

[0022] Preferably, the mass ratio of the spherical aluminum particles with particle sizes of 0.5–2 μm, 8–12 μm, 16–24 μm, and 40–60 μm is (2–4):(0.5–1.5):(0.5–1.5):(4–6), wherein 2–4 can be, for example, 2, 3, 4, etc., the two 0.5–1.5 particles can be, for example, 0.5, 0.6, 0.7, 0.8, 0.9, 1, 1.1, 1.2, 1.3, 1.4, 1.5, etc., and 4–6 can be, for example, 4, 4.5, 5, 5.5, 6, etc.

[0023] Preferably, based on the total mass of the raw materials for preparing the submersible thermal interface material as 100%, the amount of thermally conductive filler added is 85% to 95%, such as 85%, 86%, 87%, 88%, 89%, 90%, 91%, 92%, 93%, 94%, 95%, etc.

[0024] Preferably, the raw materials for preparing the submersible thermal interface material further include a catalyst.

[0025] Preferably, the catalyst comprises a platinum catalyst.

[0026] Preferably, based on the total mass of the raw materials for preparing the subsurface thermal interface material as 100%, the amount of catalyst added is 0.1% to 0.2%, for example, 0.1%, 0.12%, 0.14%, 0.16%, 0.18%, 0.2%, etc.

[0027] In a second aspect, the present invention provides a method for preparing a submersible thermal interface material as described in the first aspect, the method comprising the following steps:

[0028] (1) Mix side-chain hydrogen-based polydimethylsiloxane and double-ended vinyl polydimethylsiloxane, then add epoxy-containing acrylate monomers and / or silane coupling agents containing carbon-carbon double bonds and siloxane methyl groups, thermally conductive fillers and optional catalysts, and mix again to obtain a polymer prepolymer.

[0029] (2) The polymer prepolymer is coated on the carrier and cured to obtain the underwater thermal interface material.

[0030] Preferably, the remixing method in step (1) includes stirring.

[0031] Preferably, the stirring time is 2 to 5 minutes, for example, 2 minutes, 3 minutes, 4 minutes, 5 minutes, etc.

[0032] Preferably, the carrier in step (2) includes a substrate or a polytetrafluoroethylene film.

[0033] Preferably, the substrate comprises an aluminum plate.

[0034] Preferably, the curing temperature in step (2) is 140 to 160°C, such as 140°C, 142°C, 144°C, 146°C, 148°C, 150°C, 152°C, 154°C, 156°C, 158°C, 160°C, etc., and the curing time is 1 to 3 hours, such as 1 hour, 1.5 hours, 2 hours, 2.5 hours, 3 hours, etc.

[0035] In this invention, PDMS-H and PDMS-Vi form a basic polymer network through a hydrosilylation reaction. By controlling the molar ratio of silanol groups in the side-chain hydrogen-based polydimethylsiloxane to vinyl groups in the divinyl-terminated polydimethylsiloxane to be 1:(0.1-0.5), the polymer matrix is ​​synthesized, providing reaction sites for subsequent modification. Subsequently, for the unreacted silanol groups in PDMS-H, a chemical grafting strategy is used to introduce siloxane methyl functional groups and epoxy functional groups to enhance the polarity of the polymer matrix. The addition of thermally conductive fillers constructs a highly efficient thermally conductive network, thereby enabling the underwater thermal interface material provided by this invention to simultaneously possess high adhesion and high thermal conductivity.

[0036] The thermal interface material provided by this invention is a thermally conductive polydimethylsiloxane (PDMS) / aluminum thermal interface material. It achieves an optimized balance between inherent interfacial toughness and mechanical dissipation through synergistic strong covalent bond anchoring (using γ-methacryloyloxypropyltrimethoxysilane (γ-MPS), which can form covalent bonds with the matrix and filler) and dynamic hydrogen bond network (using 3,4-epoxycyclohexylmethacrylate (ECHMA), which can form hydrogen bonds). Specifically, by adjusting the molar ratio of ECHMA and γ-MPS, the effect of the two at the interface can be precisely controlled.

[0037] The thermal interface material provided by this invention effectively enhances adhesion and thermal conductivity, significantly improving the heat dissipation efficiency of coolant in chip liquid cooling systems, reducing chip operating temperature, and ensuring stable operation. Under this synergistic mechanism, covalent bonds, with their high bond energy, prevent crack propagation, while the reversible breaking and recombination of dynamic hydrogen bonds further enhances energy dissipation. These two factors synergistically enhance interfacial toughness and mechanical dissipation, giving the material excellent interfacial adhesion and thermal stability in underwater applications. From a societal perspective, this material can be applied to advanced microelectronics, immersion-cooled data centers, and high-density energy storage systems, addressing key challenges and driving the development of related industries. From an economic perspective, it improves equipment operating efficiency and reliability, reducing maintenance and replacement costs due to insufficient material performance, demonstrating significant economic value. Its technical effects are a direct result of the synergistic covalent bond anchoring and hydrogen bond network characteristics.

[0038] Thirdly, the present invention provides an application of the underwater thermal interface material as described in the first aspect in electronic components. In specific applications (such as in chip liquid cooling systems), the underwater thermal interface material is placed between the chip and the heat sink and completely immersed in the coolant to ensure good heat transfer and adhesion performance.

[0039] Preferably, the coolant includes a fluorinated liquid with a boiling point of 110-115°C (e.g., 110°C, 111°C, 112°C, 113°C, 114°C, 115°C, etc.).

[0040] Compared with the prior art, the present invention has the following beneficial effects:

[0041] The thermal interface material provided by this invention forms a basic polymer network by hydrosilylation reaction of side-chain hydrogen-based polydimethylsiloxane (PDMS-H) and divinyl-terminated polydimethylsiloxane (PDMS-Vi), and introduces epoxy-containing acrylate monomers and / or silane coupling agents containing carbon-carbon double bonds and siloxane methyl groups, as well as thermally conductive fillers, so that the thermal interface material has both high adhesion and high thermal conductivity when applied to coolant. Attached Figure Description

[0042] Figure 1 The synthesis mechanism diagram of the submersible thermal interface material provided in Example 2. Detailed Implementation

[0043] The technical solution of the present invention will be further illustrated below through specific embodiments. Those skilled in the art should understand that the embodiments described are merely illustrative of the present invention and should not be construed as limiting the invention in any way.

[0044] Unless otherwise specified, the following information pertains to some of the raw materials used in the following embodiments and comparative examples of this invention:

[0045] Side-chain hydrogen-based polydimethylsiloxane PDMS-H:RH-H512;

[0046] Double-ended vinyl polydimethylsiloxane PDMS-Vi: RH-Vi500E.

[0047] Example 1

[0048] This embodiment provides an underwater thermal interface material, the preparation method of which includes the following steps:

[0049] (1) Mix side-chain hydrogen-based polydimethylsiloxane PDMS-H with double-ended vinyl polydimethylsiloxane PDMS-Vi, then add 3,4-epoxycyclohexyl methacrylate ECHMA, thermally conductive filler, and platinum catalyst (5000ppm), and stir at 2000rpm for 4 minutes in a high-speed mixer at 25°C to obtain a polymer prepolymer;

[0050] The molar ratio of silane groups in PDMS-H to vinyl groups in PDMS-Vi is 1:0.3; the molar ratio of silane groups in PDMS-H to carbon-carbon double bonds in ECHMA is 1:0.7; the thermally conductive filler is spherical aluminum particles of 1μm, 10μm, 20μm, and 50μm in mass ratio of 3:1:1:5; based on the total mass of the raw materials for preparing the subsurface thermal interface material as 100%, the amount of thermally conductive filler added is 90%, and the amount of platinum catalyst added is 0.15%.

[0051] (2) The polymer prepolymer is coated on a substrate of 25.4*25.4mm with a coating area of ​​25.4*10.0mm to obtain an adhesive sample with a thickness of 0.1mm; at the same time, the polymer prepolymer is coated on a polytetrafluoroethylene film and rolled into a thermally conductive paste with a thickness of 1.5mm.

[0052] (3) Place the bonding sample and the thermally conductive paste in an oven and cure at 150°C for 2 hours to obtain the bonding sample for testing the bonding performance and the thermally conductive pad for testing the thermal conductivity, thus obtaining the underwater thermal interface material.

[0053] Example 2

[0054] This embodiment provides an underwater thermal interface material, the preparation method of which includes the following steps:

[0055] (1) Mix side-chain hydrogen-based polydimethylsiloxane PDMS-H with double-ended vinyl polydimethylsiloxane PDMS-Vi, then add 3,4-epoxycyclohexyl methacrylate ECHMA, γ-methacryloyloxypropyltrimethoxysilane γ-MPS, thermally conductive filler, and platinum catalyst (5000ppm), and stir at 2000rpm for 4 minutes in a high-speed mixer at 25°C to obtain a polymer prepolymer;

[0056] The molar ratio of silane groups in PDMS-H to vinyl groups in PDMS-Vi is 1:0.3; the molar ratio of silane groups in PDMS-H to the total carbon-carbon double bonds in ECHMA and γ-MPS is 1:0.7; the molar ratio of carbon-carbon double bonds in ECHMA to carbon-carbon double bonds in γ-MPS is 3:1; the thermally conductive filler is spherical aluminum particles of 1μm, 10μm, 20μm, and 50μm in mass ratio of 3:1:1:5; based on the total mass of the raw materials for preparing the subsurface thermal interface material as 100%, the addition amount of the thermally conductive filler is 90%, and the addition amount of the platinum catalyst is 0.15%.

[0057] (2) The polymer prepolymer is coated on a substrate of 25.4*25.4mm with a coating area of ​​25.4*10.0mm to obtain an adhesive sample with a thickness of 0.1mm; at the same time, the polymer prepolymer is coated on a polytetrafluoroethylene film and rolled into a thermally conductive paste with a thickness of 1.5mm.

[0058] (3) Place the bonding sample and the thermally conductive paste in an oven and cure at 150°C for 2 hours to obtain the bonding sample for testing the bonding performance and the thermally conductive pad for testing the thermal conductivity, thus obtaining the underwater thermal interface material.

[0059] The synthesis mechanism diagram of the submersible thermal interface material provided in this embodiment is as follows: Figure 1 As shown.

[0060] Example 3

[0061] The only difference between this embodiment and Embodiment 2 is that the molar ratio of carbon-carbon double bonds in ECHMA to carbon-carbon double bonds in γ-MPS is 1:1.

[0062] Example 4

[0063] The only difference between this embodiment and Embodiment 2 is that the molar ratio of carbon-carbon double bonds in ECHMA to carbon-carbon double bonds in γ-MPS is 1:3.

[0064] Example 5

[0065] The only difference between this embodiment and Embodiment 2 is that the molar ratio of carbon-carbon double bonds in ECHMA to carbon-carbon double bonds in γ-MPS is 0:1 (i.e., no ECHMA is added).

[0066] Example 6

[0067] The only difference between this embodiment and Embodiment 2 is that the molar ratio of silane groups in PDMS-H to vinyl groups in PDMS-Vi is 1:0.1; and the molar ratio of silane groups in PDMS-H to the total amount of carbon-carbon double bonds in ECHMA and γ-MPS is 1:0.9.

[0068] Example 7

[0069] The only difference between this embodiment and Embodiment 2 is that the molar ratio of silane groups in PDMS-H to vinyl groups in PDMS-Vi is 1:0.5; and the molar ratio of silane groups in PDMS-H to the total amount of carbon-carbon double bonds in ECHMA and γ-MPS is 1:0.5.

[0070] Example 8

[0071] The only difference between this embodiment and Embodiment 2 is that, based on the total mass of the raw materials for preparing the underwater thermal interface material being 100%, the amount of thermally conductive filler added is 85%.

[0072] Example 9

[0073] The only difference between this embodiment and Embodiment 2 is that, based on the total mass of the raw materials for preparing the underwater thermal interface material being 100%, the amount of thermally conductive filler added is 95%.

[0074] Example 10

[0075] The only difference between this embodiment and Example 2 is that 3,4-epoxycyclohexyl methacrylate (ECHMA) is replaced with an equimolar amount of glycidyl methacrylate.

[0076] Example 11

[0077] The only difference between this embodiment and Example 2 is that γ-methacryloyloxypropyltrimethoxysilane γ-MPS is replaced with an equimolar amount of vinyltrimethoxysilane.

[0078] Comparative Example 1

[0079] This comparative example provides an underwater thermal interface material, the preparation method of which includes the following steps:

[0080] (1) Mix side-chain hydrogen-based polydimethylsiloxane PDMS-H with double-ended vinyl polydimethylsiloxane PDMS-Vi, then add thermally conductive filler and platinum catalyst (5000ppm), and stir at 2000rpm for 4 minutes in a high-speed mixer at 25°C to obtain polymer prepolymer;

[0081] The molar ratio of silane-based components in PDMS-H to vinyl groups in PDMS-Vi is 1:0.3; the thermally conductive filler consists of spherical aluminum particles of 1μm, 10μm, 20μm, and 50μm in mass ratio of 3:1:1:5; based on the total mass of the raw materials for preparing the subsurface thermal interface material as 100%, the amount of thermally conductive filler added is 90%, and the amount of platinum catalyst added is 0.15%.

[0082] (2) The polymer prepolymer is coated on a substrate of 25.4*25.4mm with a coating area of ​​25.4*10.0mm to obtain an adhesive sample with a thickness of 0.1mm; at the same time, the polymer prepolymer is coated on a polytetrafluoroethylene film and rolled into a thermally conductive paste with a thickness of 1.5mm.

[0083] (3) Place the bonding sample and the thermally conductive paste in an oven and cure at 150°C for 2 hours to obtain the bonding sample for testing the bonding performance and the thermally conductive pad for testing the thermal conductivity, thus obtaining the underwater thermal interface material.

[0084] Comparative Example 2

[0085] The only difference between this comparative example and Example 2 is that 3,4-epoxycyclohexyl methacrylate (ECHMA) is replaced with an equimolar amount of butyl acrylate.

[0086] Comparative Example 3

[0087] The only difference between this comparative example and Example 2 is that γ-methacryloyloxypropyltrimethoxysilane γ-MPS is replaced with an equimolar amount of acetoxypropyltrimethoxysilane.

[0088] Comparative Example 4

[0089] The only difference between this comparative example and Example 2 is that γ-methacryloyloxypropyltrimethoxysilane γ-MPS is replaced with an equimolar amount of vinyltris(β-methoxyethoxy)silane.

[0090] The performance of the thermal interface materials provided in the embodiments and comparative examples of the present invention was tested using the following methods:

[0091] (1) Thermal conductivity test:

[0092] A standard test method for determining vertical thermal conductivity was adopted using a steady-state method. The test instrument was a thermal conductivity meter. The specific steps were as follows: a thermally conductive pad was placed between the meter bars to establish a stable heat flow through the assembly; then, the temperature in the meter bars was monitored along their length at two points; the temperature difference across the interface was calculated based on the obtained temperature readings and used to determine the thermal conductivity of the interface. The test results are shown in Table 1.

[0093] (2) Adhesion performance test:

[0094] The adhesive properties of the samples were measured using a universal tensile testing machine. The adhesive samples were tested at room temperature with a tensile speed of 10 mm / min. The test results are shown in Tables 1 and 2. In Table 1, the substrate is an aluminum plate, and in Table 2, the thermal interface material provided in Example 2 is tested. The specific substrate is shown in Table 2.

[0095] (3) Underwater high temperature bonding performance test

[0096] The thermal interface material was immersed in a fluorinated liquid (boiling point 110℃) at 100℃ for 1000 hours. The adhesive properties of the samples were then measured using a universal tensile testing machine. The adhesive samples were tested at room temperature with a tensile speed of 10 mm / min. The test results are shown in Table 3, where the substrate in Table 3 is an aluminum plate.

[0097] Table 1

[0098]

[0099]

[0100] As can be seen from Table 1, the thermal interface materials provided in the embodiments of the present invention all have high thermal conductivity (2.70~5.20W / m·K, preferably 3.91~5.20W / m·K) and bonding strength (5.32~8.05MPa).

[0101] Compared with Example 2, the thermal conductivity and bonding strength of the thermal interface material provided in Comparative Example 1 both decreased; the thermal conductivity and bonding strength of the thermal interface material provided in Comparative Example 2 both decreased; the thermal conductivity and bonding strength of the thermal interface material provided in Comparative Example 3 both decreased; and the thermal conductivity and bonding strength of the thermal interface material provided in Comparative Example 4 both decreased.

[0102] Table 2

[0103]

[0104] As can be seen from Table 2, the thermal interface material provided in Example 2 has excellent adhesion properties on various substrates.

[0105] Table 3

[0106]

[0107]

[0108] As can be seen from Table 3, the thermal interface material provided in the embodiments of the present invention still has good adhesion performance (adhesion strength: 4.60~6.90MPa) after being placed in a liquid environment for 1000h.

[0109] Compared with Example 2, the thermal interface materials provided in Comparative Examples 1-4 all have significantly lower underwater bond strength.

[0110] The applicant declares that the present invention is illustrated by the above embodiments to demonstrate the underwater thermal interface material, its preparation method, and its application. However, the present invention is not limited to the above embodiments, that is, it does not mean that the present invention must rely on the above embodiments to be implemented. Those skilled in the art should understand that any improvements to the present invention, equivalent substitutions of the raw materials used in the present invention, addition of auxiliary components, selection of specific methods, etc., all fall within the protection scope and disclosure scope of the present invention.

Claims

1. A submersible thermal interface material, characterized in that, The raw materials for preparing the submersible thermal interface material include the following components: (A) Side-chain hydrogen-based polydimethylsiloxane; (B) Dual-terminated vinyl polydimethylsiloxane; (C) Epoxy-containing acrylate monomers, and / or silane coupling agents containing carbon-carbon double bonds and siloxane methyl groups; (D) Thermally conductive filler.

2. The submersible thermal interface material according to claim 1, characterized in that, The molar ratio of the silanol group in the side-chain hydrogen-based polydimethylsiloxane to the vinyl group in the divinyl-terminated polydimethylsiloxane is 1:(0.1 to 0.5).

3. The submersible thermal interface material according to claim 1 or 2, characterized in that, The epoxy-containing acrylate monomers include 3,4-epoxycyclohexyl methacrylate and / or glycidyl methacrylate. Preferably, the silane coupling agent containing carbon-carbon double bonds and siloxane methyl groups includes γ-methacryloyloxypropyltrimethoxysilane and / or vinyltrimethoxysilane.

4. The submersible thermal interface material according to any one of claims 1-3, characterized in that, The molar ratio of the silanol group in the side-chain hydrogen-based polydimethylsiloxane to the total amount of carbon-carbon double bonds in the epoxy-containing acrylate monomer and the silane coupling agent containing carbon-carbon double bonds and siloxane methyl groups is 1:(0.5-0.9).

5. The submersible thermal interface material according to any one of claims 1-4, characterized in that, The molar ratio of the carbon-carbon double bond in the epoxy-containing acrylate monomer to the carbon-carbon double bond in the silane coupling agent containing carbon-carbon double bonds and siloxane methyl groups is (0-3):(0-3).

6. The submersible thermal interface material according to any one of claims 1-5, characterized in that, The thermally conductive filler comprises spherical aluminum particles; Preferably, the spherical aluminum particles comprise a combination of spherical aluminum particles with particle sizes of 0.5–2 μm, 8–12 μm, 16–24 μm, and 40–60 μm, respectively. Preferably, the mass ratio of the spherical aluminum particles with particle sizes of 0.5–2 μm, 8–12 μm, 16–24 μm, and 40–60 μm is (2–4):(0.5–1.5):(0.5–1.5):(4–6); Preferably, the amount of thermally conductive filler added is 85% to 95%, based on the total mass of the raw materials for preparing the submersible thermal interface material as 100%.

7. The submersible thermal interface material according to any one of claims 1-6, characterized in that, The raw materials for preparing the submersible thermal interface material also include a catalyst; Preferably, the catalyst comprises a platinum catalyst; Preferably, the amount of catalyst added is 0.1% to 0.2%, based on the total mass of the raw materials for preparing the subsurface thermal interface material as 100%.

8. A method for preparing a submersible thermal interface material as described in any one of claims 1-7, characterized in that, The preparation method includes the following steps: (1) Mix side-chain hydrogen-based polydimethylsiloxane and double-ended vinyl polydimethylsiloxane, then add epoxy-containing acrylate monomers and / or silane coupling agents containing carbon-carbon double bonds and siloxane methyl groups, thermally conductive fillers and optional catalysts, and mix again to obtain a polymer prepolymer. (2) The polymer prepolymer is coated on the carrier and cured to obtain the underwater thermal interface material.

9. The preparation method according to claim 8, characterized in that, The remixing method described in step (1) includes stirring; Preferably, the stirring time is 2 to 5 minutes; Preferably, the carrier in step (2) includes a substrate or a polytetrafluoroethylene film; Preferably, the substrate comprises an aluminum plate; Preferably, the curing temperature in step (2) is 140-160°C and the curing time is 1-3 hours.

10. The application of a submersible thermal interface material as described in any one of claims 1-7 in electronic components.

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