Organic silicon thermal conductive phase change material and preparation method thereof

Abstract

The present application provides an organosilicon thermally conductive phase-change material and a preparation method thereof. The organosilicon thermally conductive phase-change material comprises, by mass, 100 parts of ethylene cyclocarbonate-modified organopolysiloxane, 64-115 parts of amino-modified organopolysiloxane, 5.5-12 parts of cyclic acid anhydride, 2-5 parts of antioxidant, 1.5-3 parts of silane coupling agent, and 300-800 parts of thermally conductive powder. The present application does not contain a phase-change material, fundamentally solving the problem of easy leakage of phase-change materials. The cross-linked network is formed by the reaction of ethylene cyclocarbonate-modified organopolysiloxane and amino-modified organopolysiloxane. The cyclic carbonate group reacts with the amino group to produce carbamate groups and hydroxyl groups, and the cyclic acid anhydride reacts with the amino group to produce amide groups and carboxyl groups. As a result, the cross-linked network contains a large number of polar groups. At room temperature, these polar groups further form a cross-linked network. When heated, the cross-linked network weakens, and the phase-change material becomes viscous, achieving the phase-change function.

Description

Technical Field

[0001] The present application relates to the technical field of thermal conductive phase change materials, and in particular to an organic silicon thermal conductive phase change material and a preparation method thereof. Background Art

[0002] With technological advancements, the circuit designs of modern electronic devices are becoming increasingly complex and integrated. To ensure the stable operation of these highly integrated devices, the heat generated by each electronic component must be effectively and promptly transferred away. Thermally conductive interface materials can effectively fill the air gap between the heat-generating device and the heat sink, creating an optimal heat transfer path and improving the device's heat dissipation efficiency.

[0003] Thermally conductive phase change materials (PCMs) are composite materials that change from a solid state to a soft or fluid state with temperature, reducing interfacial thermal resistance and improving heat conduction. PCMs are solid at room temperature, making them easy to process and handle. They can be used as thermal interface materials on heat sinks or electronic device surfaces. When the temperature reaches the phase transition point, the PCM becomes viscous, similar to a thermally conductive gel, effectively filling interfacial gaps and significantly reducing thermal resistance, thereby significantly improving thermal conductivity.

[0004] Thermally conductive phase-change materials generally consist of a polymer matrix, a phase-change material, and a thermally conductive filler. The phase-change material imparts phase-change properties to the material. Commonly used phase-change materials include paraffin wax, polyols, and carboxylic acid esters. For example, patent CN105315414A discloses a phase-change thermally conductive silicone sheet composed of a matrix material, a thermally conductive filler, a long-chain alkyl olefin material, an antioxidant, and a surface treatment agent. Patent CN115785677A discloses a single-component phase-change silicone thermally conductive gel composed of vinyl silicone oil, hydrogenated silicone oil, a catalyst, paraffin-coated phase-change microcapsules, a thixotropic agent, a coupling agent, and a thermally conductive filler.

[0005] However, during the storage and application of this type of thermally conductive phase change material, the phase change material is prone to leak from the matrix, thereby affecting the thermal conductivity of the phase change material. Summary of the Invention

[0006] In view of the above-mentioned problems, the present application is proposed to provide an organic silicon thermal conductive phase change material and a preparation method thereof that overcomes the problems or at least partially solves the problems, including:

[0007] A silicone thermally conductive phase change material comprises, by mass, 100 parts of ethylene cyclocarbonate-modified organopolysiloxane, 64-115 parts of amino-modified organopolysiloxane, 5.5-12 parts of cyclic acid anhydride, 2-5 parts of antioxidant, 1.5-3 parts of silane coupling agent, and 300-800 parts of thermally conductive powder; wherein the ethylene cyclocarbonate-modified organopolysiloxane is an organopolysiloxane in which cyclocarbonate groups are introduced at both ends of the molecular chain.

[0008] Preferably, the structural formula of the ethylene cyclocarbonate modified organopolysiloxane is:

[0009]

[0010] Among them, a=30~60, b=0~5.

[0011] Preferably, the amino-modified organopolysiloxane has the structural formula:

[0012]

[0013] Wherein, c=35-100, d=10-20, R is -(CH2)3NH2, -(CH2)3NH(CH2)3NH2 or

[0014] Preferably, the cyclic anhydride includes at least one of maleic anhydride, succinic anhydride, phthalic anhydride, hexahydrophthalic anhydride, tetrahydrophthalic anhydride and methylhexahydrophthalic anhydride.

[0015] Preferably, the antioxidant includes at least one of tris(2,4-di-tert-butylphenyl)phosphite, pentaerythritol tetrakis[methyl-β-(3,5-di-tert-butyl-4-hydroxyphenyl)propionate], 2,6-di-tert-butyl-4-methylphenol, 1,1,3-tris(2-methyl-4-hydroxy-5-tert-butylphenyl)butane and 4,4'-methylenebis(2,6-di-tert-butylphenol).

[0016] Preferably, the silane coupling agent includes at least one of 3-aminopropylethoxysiloxane, γ-glycidyloxypropyltrimethoxysilane, γ-(methacryloyloxy)propyltrimethoxysilane, dodecyltrimethoxysilane, vinyltriethoxysilane, titanate coupling agent and aluminate coupling agent.

[0017] Preferably, the thermally conductive powder includes at least one of aluminum oxide, magnesium oxide, zinc oxide, aluminum nitride, boron nitride, silicon nitride, silicon carbide, carbon fiber and graphene.

[0018] A method for preparing the organic silicon thermal conductive phase change material as described in any one of the above items comprises:

[0019] Mixing the ethylene carbonate-modified organopolysiloxane, the cyclic acid anhydride, the antioxidant, the silane coupling agent, and the thermally conductive powder to obtain a first mixture;

[0020] mixing the amino-modified organopolysiloxane with the first mixture under vacuum to obtain a second mixture;

[0021] The second mixture is calendered and heated to be cured to obtain the organic silicon thermal conductive phase change material.

[0022] Preferably, it also includes:

[0023] Mixing organohydrogen polysiloxane and vinylene carbonate, and heating to 100-130° C. under nitrogen protection;

[0024] adding a platinum catalyst to allow the organohydrogenpolysiloxane and the vinylene carbonate to fully react to obtain a reactant;

[0025] The reactants are heated to 150° C., and excess vinylene carbonate is removed under vacuum to obtain the vinylene carbonate-modified organopolysiloxane.

[0026] Preferably, the structural formula of the organohydrogenpolysiloxane is:

[0027]

[0028] Among them, a=30~60, b=0~5.

[0029] This application has the following advantages:

[0030] In the embodiments of the present application, with respect to the problem that the phase change material in the existing thermal conductive phase change material is easy to leak from the matrix, the present application provides a solution of removing the phase change material and using ethylene carbonate modified organic polysiloxane, amino modified organic polysiloxane and cyclic acid anhydride as the polymer matrix, specifically: "A silicone thermal conductive phase change material, comprising, by mass: 100 parts of ethylene carbonate modified organic polysiloxane, 64-115 parts of amino modified organic polysiloxane, 5.5-12 parts of cyclic acid anhydride, 2-5 parts of antioxidant, 1.5-3 parts of silane coupling agent and 300-800 parts of thermal conductive powder; wherein, the ethylene carbonate modified organic polysiloxane is an organic polysiloxane with cyclic carbonate groups introduced at both ends of the molecular chain." Compared with existing thermally conductive phase change materials, the organic silicon thermally conductive phase change material does not contain phase change substances, which fundamentally solves the problem of phase change substances easily leaking from the organic silicon matrix; the cross-linked network is formed by the reaction of the ethylene carbonate-modified organic polysiloxane and the amino-modified organic polysiloxane, which can fix the thermally conductive powder inside, ensuring that the thermally conductive powder will not precipitate when the organic silicon thermally conductive phase change material is heated; the cyclic carbonate group reacts with the amino group to produce carbamate groups and hydroxyl groups, and the cyclic anhydride reacts with the amino group to produce amide groups and carboxyl groups, so that the cross-linked network contains a large number of polar groups. At room temperature, these polar groups further form a cross-linked network under the action of hydrogen bonds, and the organic silicon thermally conductive phase change material is solid. When heated, the force of the hydrogen bonds weakens, the cross-linked network weakens, and the organic silicon thermally conductive phase change material becomes a viscous body, realizing the phase change function. BRIEF DESCRIPTION OF THE DRAWINGS

[0031] In order to more clearly illustrate the technical solution of the present application, the following is a brief introduction to the drawings required for the description of the present application. Obviously, the drawings described below are only some embodiments of the present application. For ordinary technicians in this field, other drawings can be obtained based on these drawings without any creative work.

[0032] Figure 1 This is a flow chart of the steps of a method for preparing an organosilicon thermal conductive phase change material provided in one embodiment of the present application;

[0033] Figure 2 This is a flow chart of the steps of a method for preparing an organosilicon thermal conductive phase change material provided in another embodiment of the present application. DETAILED DESCRIPTION

[0034] To make the objectives, features, and advantages of this application more readily apparent, the present application is further described below in conjunction with the accompanying drawings and specific embodiments. Obviously, the embodiments described are only a portion of the embodiments of this application, not all of them. All other embodiments derived by persons of ordinary skill in the art based on the embodiments in this application without inventive effort are also within the scope of protection of this application.

[0035] By analyzing the existing technology, the inventors found that due to the poor compatibility of phase change materials such as paraffin, polyols and carboxylates with silicone, the phase change materials added with these phase change materials are prone to leak from the silicone matrix during storage and application, thereby affecting the thermal conductivity of the thermal conductive phase change material.

[0036] In one embodiment of the present application, a silicone thermally conductive phase change material is provided, comprising, by mass, 100 parts of ethylene cyclocarbonate-modified organopolysiloxane, 64-115 parts of amino-modified organopolysiloxane, 5.5-12 parts of cyclic acid anhydride, 2-5 parts of antioxidant, 1.5-3 parts of silane coupling agent, and 300-800 parts of thermally conductive powder; wherein the ethylene cyclocarbonate-modified organopolysiloxane is an organopolysiloxane in which cyclocarbonate groups are introduced at both ends of the molecular chain.

[0037] In the embodiments of the present application, with respect to the problem that the phase change material in the existing thermal conductive phase change material is easy to leak from the matrix, the present application provides a solution of removing the phase change material and using ethylene carbonate modified organic polysiloxane, amino modified organic polysiloxane and cyclic acid anhydride as the polymer matrix, specifically: "A silicone thermal conductive phase change material, comprising, by mass: 100 parts of ethylene carbonate modified organic polysiloxane, 64-115 parts of amino modified organic polysiloxane, 5.5-12 parts of cyclic acid anhydride, 2-5 parts of antioxidant, 1.5-3 parts of silane coupling agent and 300-800 parts of thermal conductive powder; wherein, the ethylene carbonate modified organic polysiloxane is an organic polysiloxane with cyclic carbonate groups introduced at both ends of the molecular chain." Compared with existing thermally conductive phase change materials, the organic silicon thermally conductive phase change material does not contain phase change substances, which fundamentally solves the problem of phase change substances easily leaking from the organic silicon matrix; the cross-linked network is formed by the reaction of the ethylene carbonate-modified organic polysiloxane and the amino-modified organic polysiloxane, which can fix the thermally conductive powder inside, ensuring that the thermally conductive powder will not precipitate when the organic silicon thermally conductive phase change material is heated; the cyclic carbonate group reacts with the amino group to produce carbamate groups and hydroxyl groups, and the cyclic anhydride reacts with the amino group to produce amide groups and carboxyl groups, so that the cross-linked network contains a large number of polar groups. At room temperature, these polar groups further form a cross-linked network under the action of hydrogen bonds, and the organic silicon thermally conductive phase change material is solid. When heated, the force of the hydrogen bonds weakens, the cross-linked network weakens, and the organic silicon thermally conductive phase change material becomes a viscous body, realizing the phase change function.

[0038] Next, an organosilicon thermal conductive phase change material in this exemplary embodiment will be further described.

[0039] In this embodiment, the ethylene cyclocarbonate-modified organopolysiloxane is an organopolysiloxane having cyclocarbonate groups introduced only at the chain ends, or an organopolysiloxane having cyclocarbonate groups introduced both at the chain ends and on the side chains. Preferably, the organopolysiloxane has cyclocarbonate groups introduced both at the chain ends and on the side chains. It should be noted that the crosslinked network formed by the reaction of the cyclocarbonate groups introduced at the chain ends with the amino groups is relatively stable, which helps maintain the basic form of the organosilicon thermally conductive phase-change material. In contrast, the crosslinked network formed by the reaction of the cyclocarbonate groups introduced at the side chains with the amino groups is relatively loose, which helps achieve the phase change function of the organosilicon thermally conductive phase-change material.

[0040] In this embodiment, the structural formula of the ethylene cyclocarbonate-modified organopolysiloxane is:

[0041]

[0042] Among them, a=30~60, b=0~5.

[0043] In this embodiment, the amino-modified organopolysiloxane is an organohydrogenpolysiloxane with amino groups or their derivatives introduced into the side chains. The amino derivatives include any of aminomethyl, nitrilo, isocyanate, imino, urea, amide, amino acid, and amino-containing heterocyclic groups. The amino-modified organopolysiloxane can react with the ethylene cyclocarbonate-modified organopolysiloxane to form a cross-linked network, securing the thermally conductive powder within and preventing it from precipitating when the organosilicon thermally conductive phase-change material is heated. The amino groups can also react with cyclocarbonate and cyclic anhydride groups to produce polar groups, thereby achieving the phase change function of the organosilicon thermally conductive phase-change material.

[0044] In this embodiment, the structural formula of the amino-modified organopolysiloxane is:

[0045]

[0046] Wherein, c=35-100, d=10-20, R is -(CH2)3NH2, -(CH2)3NH(CH2)3NH2 or

[0047] In this embodiment, the cyclic anhydride is a molecule containing a cyclic anhydride group, including at least one of maleic anhydride, succinic anhydride, phthalic anhydride, hexahydrophthalic anhydride, tetrahydrophthalic anhydride, and methylhexahydrophthalic anhydride. The cyclic anhydride can provide cyclic anhydride groups that react with amino groups to produce polar groups, thereby achieving the phase change function of the organosilicon thermally conductive phase change material. It can also serve as a curing agent, collaborating with the silane coupling agent to promote bonding between different materials.

[0048] In this embodiment, the antioxidant includes at least one of tris(2,4-di-tert-butylphenyl) phosphite (i.e., antioxidant 168), pentaerythritol tetrakis(methyl-β-(3,5-di-tert-butyl-4-hydroxyphenyl) propionate) (i.e., antioxidant 1010), 2,6-di-tert-butyl-4-methylphenol (i.e., BHT), 1,1,3-tris(2-methyl-4-hydroxy-5-tert-butylphenyl)butane (i.e., antioxidant CA), and 4,4'-methylenebis(2,6-di-tert-butylphenol) (i.e., antioxidant 702). These antioxidants can stabilize other components, delaying or inhibiting the oxidation reaction of the organosilicon thermally conductive phase change material, and preventing aging, degradation, and deterioration.

[0049] In this embodiment, the silane coupling agent includes at least one of 3-aminopropylethoxysiloxane (i.e., KH550), γ-glycidoxypropyltrimethoxysilane (i.e., KH560), γ-(methacryloyloxy)propyltrimethoxysilane (i.e., KH570), dodecyltrimethoxysilane, vinyltriethoxysilane, titanate coupling agent, and aluminate coupling agent. The silane coupling agent can bond one end of the silane molecule to an inorganic molecule and the other end to an organic molecule, thereby achieving a good coupling effect between the organic and inorganic molecules and enhancing the mechanical properties and chemical stability of the organosilicon thermal conductive phase change material.

[0050] In this embodiment, the thermally conductive powder includes at least one of aluminum oxide, magnesium oxide, zinc oxide, aluminum nitride, boron nitride, silicon nitride, silicon carbide, carbon fiber, and graphene. The thermally conductive powder is added as a filler to enhance the thermal conductivity of the organic silicon thermally conductive phase change material.

[0051] Reference Figure 1 In one embodiment of the present application, a method for preparing the organic silicon thermal conductive phase change material as described in any of the above embodiments is provided, comprising:

[0052] S110, mixing the ethylene cyclocarbonate-modified organopolysiloxane, the cyclic acid anhydride, the antioxidant, the silane coupling agent, and the thermally conductive powder to obtain a first mixture;

[0053] S120, mixing the amino-modified organopolysiloxane with the first mixture to obtain a second mixture;

[0054] S130, calendering and heating the second mixture to obtain the organic silicon thermal conductive phase change material.

[0055] As described in step S110 , the ethylene cyclocarbonate-modified organopolysiloxane, the cyclic acid anhydride, the antioxidant, the silane coupling agent, and the thermally conductive powder are mixed to obtain a first mixture.

[0056] The ethylene cyclocarbonate-modified organopolysiloxane, the cyclic acid anhydride, the antioxidant, and the silane coupling agent are added to a mixing container according to a specific ratio and thoroughly stirred. The thermally conductive powder is then gradually added to the mixing container and continuously stirred until the thermally conductive powder is evenly dispersed in the system, thereby obtaining the first mixture. The mixing temperature of the first mixture is 70-100° C., and the mixing time is 1-2 hours.

[0057] As described in step S120, the amino-modified organopolysiloxane is mixed with the first mixture under vacuum to obtain a second mixture.

[0058] The amino-modified organopolysiloxane is added to the mixing container and continuously stirred and mixed under vacuum to obtain the second mixture. The mixing temperature of the second mixture is 20 to 30° C., the mixing time is 10 to 20 minutes, and the relative vacuum pressure is -0.1 to -0.08 MPa.

[0059] As described in step S130, the second mixture is rolled and heated to be cured to obtain the organic silicon thermal conductive phase change material.

[0060] The second mixture is rolled into a sheet with a thickness of 0.5 to 6 mm, and heated and solidified, and then cooled to obtain the organic silicon thermal conductive phase change material.

[0061] Reference Figure 2 In this embodiment, the preparation method further includes:

[0062] S010, mixing organohydrogenpolysiloxane and vinylene carbonate, and heating to 100-130° C. under nitrogen protection;

[0063] S020, adding a platinum catalyst to allow the organohydrogenpolysiloxane and the vinylene carbonate to fully react to obtain a reactant;

[0064] S030, heating the reactants to 150° C. and removing excess vinylene carbonate under vacuum to obtain the vinylene carbonate-modified organopolysiloxane.

[0065] As described in step S010 , the organohydrogenpolysiloxane and vinylene carbonate are mixed and heated to 100-130° C. under nitrogen protection.

[0066] The organohydrogenpolysiloxane and an excess of vinylene carbonate are added to a reaction vessel and heated to 100-130° C. under nitrogen protection. The structural formula of the organohydrogenpolysiloxane is:

[0067]

[0068] Among them, a=30~60, b=0~5.

[0069] As described in step S020, a platinum catalyst is added to allow the organohydrogenpolysiloxane and the vinylene carbonate to fully react to obtain a reactant.

[0070] The platinum catalyst is added to allow the organohydrogen polysiloxane and the vinylene carbonate to react until the infrared absorption peak of the Si-H group disappears, thereby obtaining the reactant. The synthetic reaction formula is:

[0071]

[0072] Wherein, the molar ratio of vinylene carbonate to Si—H is (1.03-1.1):1.

[0073] As described in step S030, the reactants are heated to 150°C, and excess vinylene carbonate is removed under vacuum to obtain the vinylene carbonate-modified organopolysiloxane.

[0074] The reactants are heated to 150° C., and excess vinylene carbonate is removed under vacuum to obtain the vinylene carbonate-modified organopolysiloxane.

[0075] The following are specific embodiments of the present application:

[0076] Synthesis example 1

[0077] In a reaction flask equipped with a stirrer, a thermometer, and a nitrogen inlet, 100 parts by mass of organohydrogenpolysiloxane and 7.6 parts of vinylene carbonate were added, stirred, and heated to 100°C under nitrogen. 0.5 parts of 3000 ppm Karstedt catalyst were added and reacted for a certain period of time. Samples were taken and the Si-H content in the reaction system was detected by infrared spectrometer until the absorption peak of the Si-H group disappeared. The reaction was then heated to 150°C and vacuumed to remove excess vinylene carbonate, thereby obtaining a vinyl cyclocarbonate-modified organopolysiloxane. The structural formula of the organohydrogenpolysiloxane is:

[0078]

[0079] The structural formula of the ethylene cyclocarbonate modified organopolysiloxane is:

[0080]

[0081] Synthesis example 2

[0082] In a reaction flask equipped with a stirrer, a thermometer, and a nitrogen inlet, 100 parts by mass of organohydrogenpolysiloxane and 13 parts by mass of vinylene carbonate were added, stirring was started, and under nitrogen protection, the mixture was heated to 130°C. 0.1 parts of 6000 ppm Karstedt catalyst was added, and the reaction was continued for a certain period of time. Samples were taken and the Si-H content in the reaction system was detected by infrared spectrometer until the absorption peak of the Si-H group disappeared. The mixture was then heated to 150°C and vacuumed to remove excess vinylene carbonate, thereby obtaining a vinyl cyclocarbonate-modified organopolysiloxane. The structural formula of the organohydrogenpolysiloxane is:

[0083]

[0084] The structural formula of the ethylene cyclocarbonate modified organopolysiloxane is:

[0085]

[0086] Synthesis example 3

[0087] In a reaction flask equipped with a stirrer, a thermometer, and a nitrogen inlet, 100 parts by mass of organohydrogenpolysiloxane and 11.5 parts of vinylene carbonate were added, and stirring was started. Under nitrogen protection, the mixture was heated to 105°C, and 0.2 parts of 5000 ppm Speier catalyst was added. The reaction was allowed to proceed for a certain period of time. Samples were taken and the Si-H content in the reaction system was detected by infrared spectrometer until the absorption peak of the Si-H group disappeared. The reaction was then heated to 150°C and vacuumed to remove excess vinylene carbonate, thereby obtaining a vinyl cyclocarbonate-modified organopolysiloxane. The structural formula of the organohydrogenpolysiloxane is:

[0088]

[0089] The structural formula of the ethylene cyclocarbonate modified organopolysiloxane is:

[0090]

[0091] Example 1

[0092] In parts by mass, 100 parts of the ethylene carbonate-modified organopolysiloxane of Synthesis Example 1, 7.7 parts of maleic anhydride, 3 parts of antioxidant 1010, 3 parts of titanate coupling agent and 500 parts of aluminum nitride were heated to 80° C. and stirred for 2 hours to obtain a first mixture; 78.5 parts of amino-modified organopolysiloxane were added to the first mixture, and the mixture was stirred at 25° C. for 15 minutes under a vacuum degree of -0.08 MPa to obtain a second mixture; the second mixture was rolled into a 2 mm thick sheet, heated and cured at 80° C. for 8 hours, and cooled to obtain an organosilicon thermal conductive phase change material; wherein the structural formula of the amino-modified organopolysiloxane is:

[0093]

[0094] Example 2

[0095] In parts by mass, 100 parts of the ethylene cyclocarbonate-modified organopolysiloxane of Synthesis Example 2, 6.4 parts of succinic anhydride, 4 parts of BHT, 1.5 parts of dodecyltrimethoxysilane and 300 parts of boron nitride were heated to 90° C. and stirred for 2 hours to obtain a first mixture; 65.5 parts of amino-modified organopolysiloxane were added to the first mixture, and the mixture was stirred at 25° C. for 10 minutes under a vacuum degree of -0.09 MPa to obtain a second mixture; the second mixture was rolled into a 2 mm thick sheet, heated and cured at 50° C. for 7 hours, and cooled to obtain an organosilicon thermal conductive phase change material; wherein the structural formula of the amino-modified organopolysiloxane is:

[0096]

[0097] Example 3

[0098] In parts by mass, 100 parts of the ethylene carbonate-modified organopolysiloxane of Synthesis Example 2, 9.8 parts of maleic anhydride, 6 parts of antioxidant 1010, 2 parts of aluminate coupling agent, 200 parts of boron nitride and 300 parts of aluminum nitride were heated to 80° C. and stirred for 2 hours to obtain a first mixture; 115 parts of amino-modified organopolysiloxane were added to the first mixture, and the mixture was stirred at 20° C. for 15 minutes under a vacuum degree of -0.1 MPa to obtain a second mixture; the second mixture was rolled into a 2 mm thick sheet, heated and cured at 70° C. for 3 hours, and cooled to obtain an organosilicon thermal conductive phase change material; wherein the structural formula of the amino-modified organopolysiloxane is:

[0099]

[0100] Example 4

[0101] In parts by mass, 100 parts of the ethylene carbonate-modified organopolysiloxane of Synthesis Example 3, 6.9 parts of hexahydrophthalic anhydride, 4 parts of BHT, 5 parts of KH550 and 800 parts of aluminum oxide were heated to 70° C. and stirred for 1 hour to obtain a first mixture; 99 parts of amino-modified organopolysiloxane were added to the first mixture, and the mixture was stirred at 20° C. for 10 minutes under a vacuum degree of -0.1 MPa to obtain a second mixture; the second mixture was rolled into a 2 mm thick sheet, heated and cured at 60° C. for 8 hours, and cooled to obtain an organosilicon thermal conductive phase change material; wherein the structural formula of the amino-modified organopolysiloxane is:

[0102]

[0103] Example 5

[0104] In parts by mass, 100 parts of the ethylene carbonate-modified organopolysiloxane of Synthesis Example 3, 11.7 parts of phthalic anhydride, 5 parts of antioxidant 168, 3 parts of KH550 and 600 parts of aluminum oxide were heated to 100° C. and stirred for 2 hours to obtain a first mixture; 96 parts of amino-modified organopolysiloxane were added to the first mixture, and the mixture was stirred at 30° C. for 15 minutes under a vacuum degree of -0.1 MPa to obtain a second mixture; the second mixture was rolled into a 2 mm thick sheet, heated and cured at 80° C. for 8 hours, and cooled to obtain an organosilicon thermal conductive phase change material; wherein the structural formula of the amino-modified organopolysiloxane is:

[0105]

[0106] Example 6

[0107] In parts by mass, 100 parts of the ethylene carbonate-modified organopolysiloxane of Synthesis Example 3, 5.5 parts of maleic anhydride, 4 parts of antioxidant 168, 2 parts of KH560 and 500 parts of boron nitride were heated to 80° C. and stirred for 2 hours to obtain a first mixture; 96 parts of amino-modified organopolysiloxane were added to the first mixture, and the mixture was stirred at 20° C. for 15 minutes under a vacuum degree of -0.1 MPa to obtain a second mixture; the second mixture was rolled into a 2 mm thick sheet, heated and cured at 70° C. for 5 hours, and cooled to obtain an organosilicon thermal conductive phase change material; wherein the structural formula of the amino-modified organopolysiloxane is:

[0108]

[0109] The organosilicon thermally conductive phase-change materials prepared in Examples 1-6 were subjected to thermal conductivity, phase change, and leakage tests. Thermal conductivity was tested according to ISO 22007-2. The phase change test involved heating the thermally conductive phase-change materials to a specified temperature and measuring their hardness or observing their state. The leakage test involved placing the thermally conductive phase-change materials on filter paper, baking them at 60°C for 72 hours, and observing the presence of precipitates on the filter paper. The results are shown in Table 1.

[0110]

[0111] Table 1 Phase change material performance table of Examples 1 to 6

[0112] It can be seen from the test results that the organic silicon thermal conductive phase change material provided in this application has good phase change characteristics, does not leak, has a large controllable range of thermal conductivity, and has broad application prospects.

[0113] Although preferred embodiments of the present invention have been described, those skilled in the art may make additional changes and modifications to these embodiments once they become aware of the basic inventive concepts. Therefore, the appended claims are intended to be interpreted as including the preferred embodiments and all changes and modifications that fall within the scope of the embodiments of the present invention.

[0114] Finally, it should be noted that, in this document, relational terms such as first and second, etc., are used only to distinguish one entity or operation from another entity or operation, and do not necessarily require or imply any actual relationship or order between these entities or operations. Moreover, the terms "comprises," "comprising," or any other variations thereof are intended to cover non-exclusive inclusion, such that a process, method, article, or terminal device that includes a series of elements includes not only those elements, but also other elements not explicitly listed, or elements inherent to such process, method, article, or terminal device. In the absence of further limitations, an element defined by the phrase "comprising a ..." does not exclude the presence of additional identical elements in the process, method, article, or terminal device that includes the element.

[0115] The above is a detailed introduction to the organic silicone thermal conductive phase change material and its preparation method provided by the present application. Specific examples are used herein to illustrate the principles and implementation methods of the present application. The description of the above embodiments is only used to help understand the method of the present application and its core idea. At the same time, for general technical personnel in this field, based on the ideas of the present application, there will be changes in the specific implementation methods and application scope. In summary, the content of this specification should not be understood as a limitation on the present application.

Claims

1. An organic silicon thermal conductive phase change material, characterized in that: The composition comprises, by mass, 100 parts of ethylene cyclocarbonate-modified organopolysiloxane, 64-115 parts of amino-modified organopolysiloxane, 5.5-12 parts of cyclic acid anhydride, 2-5 parts of antioxidant, 1.5-3 parts of silane coupling agent and 300-800 parts of thermal conductive powder; wherein the ethylene cyclocarbonate-modified organopolysiloxane is an organopolysiloxane having cyclic carbonate groups introduced at both ends of the molecular chain; the amino-modified organopolysiloxane is an organohydrogenpolysiloxane having amino groups or amino derivatives introduced at the chain side; and the cyclic acid anhydride comprises at least one of maleic anhydride, succinic anhydride, phthalic anhydride, hexahydrophthalic anhydride, tetrahydrophthalic anhydride and methylhexahydrophthalic anhydride.

2. The organic silicon thermal conductive phase change material according to claim 1, characterized in that: The structural formula of the ethylene cyclocarbonate modified organopolysiloxane is: Among them, a=30~60, b=0~5.

3. The organic silicon thermal conductive phase change material according to claim 1, characterized in that: The structural formula of the amino-modified organopolysiloxane is: Wherein, c=35-100, d=10-20, R is -(CH2)3NH2, -(CH2)3NH(CH2)3NH2 or 4. The organic silicon thermal conductive phase change material according to claim 1, characterized in that: The antioxidant includes at least one of tris(2,4-di-tert-butylphenyl)phosphite, pentaerythritol tetrakis[methyl-β-(3,5-di-tert-butyl-4-hydroxyphenyl)propionate], 2,6-di-tert-butyl-4-methylphenol, 1,1,3-tris(2-methyl-4-hydroxy-5-tert-butylphenyl)butane and 4,4'-methylenebis(2,6-di-tert-butylphenol).

5. The organic silicon thermal conductive phase change material according to claim 1, characterized in that: The silane coupling agent includes at least one of 3-aminopropylethoxysiloxane, γ-glycidyloxypropyltrimethoxysilane, γ-(methacryloyloxy)propyltrimethoxysilane, dodecyltrimethoxysilane, vinyltriethoxysilane, titanate coupling agent and aluminate coupling agent.

6. The organic silicon thermal conductive phase change material according to claim 1, characterized in that: The thermally conductive powder includes at least one of aluminum oxide, magnesium oxide, zinc oxide, aluminum nitride, boron nitride, silicon nitride, silicon carbide, carbon fiber and graphene.

7. A method for preparing the organic silicon thermal conductive phase change material according to any one of claims 1 to 6, characterized in that: include: Mixing the ethylene carbonate-modified organopolysiloxane, the cyclic acid anhydride, the antioxidant, the silane coupling agent, and the thermally conductive powder to obtain a first mixture; mixing the amino-modified organopolysiloxane with the first mixture under vacuum to obtain a second mixture; The second mixture is calendered and heated to be cured to obtain the organic silicon thermal conductive phase change material.

8. The preparation method according to claim 7, characterized in that Also includes: Mixing organohydrogen polysiloxane and vinylene carbonate, and heating to 100-130° C. under nitrogen protection; adding a platinum catalyst to allow the organohydrogenpolysiloxane and the vinylene carbonate to fully react to obtain a reactant; The reactants are heated to 150° C., and excess vinylene carbonate is removed under vacuum to obtain the vinylene carbonate-modified organopolysiloxane.

9. The preparation method according to claim 8, characterized in that The structural formula of the organohydrogenpolysiloxane is: Among them, a=30~60, b=0~5.

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