CN116254003A - High-heat-conductivity wave-absorbing rubber sheet and preparation method thereof - Google Patents

Abstract

The invention discloses a high-heat-conductivity wave-absorbing rubber sheet and a preparation method thereof. The preparation raw materials comprise, by mass, 100 parts of vinyl silicone oil, 200-800 parts of carbonyl iron, 100-300 parts of silicon carbide, 100-300 parts of phase-change microcapsules, 400-1000 parts of diamond, 2-8 parts of cross-linking agents, 0.1-0.8 part of inhibitors, 0.1-0.8 part of platinum catalysts and 1-5 parts of coupling agents. The preparation method comprises the following steps: adding vinyl silicone oil, carbonyl iron, silicon carbide, phase-change microcapsules, diamond and a coupling agent into a stirrer, stirring uniformly at high temperature, adding a cross-linking agent, an inhibitor and a platinum catalyst after the materials are cooled, stirring uniformly, and finally obtaining the high-heat-conductivity wave-absorbing rubber sheet after vacuum defoamation, calendaring into sheets and hot air vulcanization. The invention uses the magnetic material flaky carbonyl iron to compound with silicon carbide and diamond, and adds the phase change microcapsule, thereby obviously improving the wave-absorbing efficiency and the heat-conducting property of the rubber material.

Description

High-heat-conductivity wave-absorbing rubber sheet and preparation method thereof

Technical Field

The invention belongs to the technical field of functional polymer composite materials, and particularly relates to a high-heat-conductivity wave-absorbing rubber sheet and a preparation method thereof.

Background

The rubber wave absorbing material is a functional material capable of converting electromagnetic waves into heat energy or other forms of energy through electric loss or magnetic loss so as to absorb most or even all electromagnetic waves. The wave-absorbing material can be used as an effective radar stealth and high-sensitivity anti-electromagnetic interference medium, and has wide application in the aspects of military stealth, wave absorption of microwave devices, electromagnetic interference resistance of electronic communication and the like.

With the increase of power and integration of electronic devices, the internal power density is higher and higher, and a large amount of heat is generated in the use process of the devices. Because the internal space of the electronic equipment is narrow and the air circulation performance is poor, heat is difficult to conduct and radiate to the outside in time, so that the temperature of the electronic equipment and devices is increased, and the working performance of the equipment is reduced. Therefore, the flexible heat-conducting rubber can be used for solving the problem of heat dissipation of electronic components, timely guiding out heat generated in the electronic equipment and avoiding the problem of overheating of the electronic components. In addition, the wave absorbing material can be used for solving the problems of electromagnetic interference, information leakage and the like in electronic equipment. Because the internal space of the electronic equipment is narrow, the flexible heat-conducting rubber occupies the gap space of the device, and the wave-absorbing gasket is difficult to stack. Therefore, a heat-conducting wave-absorbing material needs to be developed, which has high heat-conducting coefficient and certain wave-absorbing performance on one hand, and can effectively solve the problems of heat dissipation and electromagnetic interference in electronic equipment.

Disclosure of Invention

In order to solve the technical problems in the prior art, the invention provides a high-heat-conductivity wave-absorbing rubber sheet and a preparation method thereof. According to the invention, liquid silicon rubber is used as a matrix, diamond and phase-change microcapsules are used as heat-conducting fillers, flaky carbonyl iron and silicon carbide are used as wave-absorbing fillers, and a processing aid and a crosslinking system are optimized, so that the rubber sheet with high heat conduction and wave absorption is obtained.

The high-heat-conductivity wave-absorbing rubber sheet comprises, by mass, 100 parts of vinyl silicone oil, 200-800 parts of carbonyl iron, preferably 300-500 parts of silicon carbide, preferably 100-200 parts of phase-change microcapsules, preferably 100-150 parts of phase-change microcapsules, 400-1000 parts of diamond, preferably 500-800 parts of cross-linking agents, 2-8 parts of cross-linking agents, preferably 3-4.5 parts of inhibitors, 0.1-0.8 part of platinum catalysts, preferably 0.3-0.4 part of platinum catalysts, 0.1-0.8 part of platinum catalysts, preferably 0.5-0.6 part of coupling agents, and 1-5 parts of coupling agents, preferably 3-4 parts of coupling agents.

The coupling agent is one or more of silane coupling agent, stearic acid and unsaturated organic acid.

The vinyl silicone oil is one or more of vinyl end-capped polydimethylsiloxane, end-side vinyl silicone oil, methyl end-side vinyl silicone oil and partial end-capped vinyl silicone oil. The viscosity of the vinyl silicone oil is 100-400mpa.s.

The cross-linking agent is one or more of hydrogen-terminated polydimethylsiloxane, hydrogen-terminated polydimethylsiloxane and partial hydrogen-terminated polydimethylsiloxane. The viscosity of the crosslinker is from 10 to 15mpa.s.

The carbonyl iron is lamellar carbonyl iron wave absorber, and the D50 particle size is 2-8 mu m. The lamellar carbonyl iron wave absorber has the characteristics of high dielectric constant and high magnetic loss, and can effectively absorb electromagnetic waves at low frequency compared with the traditional magnetic filler spherical carbonyl iron.

The silicon carbide is spherical heat-conducting wave-absorbing material, and the D50 particle size is 30-60 mu m. Silicon carbide belongs to a resistive wave-absorbing material, and electromagnetic energy is mainly attenuated on a material resistor; also has excellent thermal physical properties, in particular high temperature resistance, high strength, low creep, high thermal conductivity, small expansion coefficient, strong corrosion resistance and good chemical stability.

The diamond is a non-regular polyhedron with a D50 particle size of 90-150 μm, preferably 100-130 μm. Diamond is a mineral composed of carbon elements, and is an allotrope of graphite; has the characteristics of high hardness, high melting point, high insulativity, chemical stability, acid and alkali corrosion resistance and the like; diamond atoms are composed of a pure carbon backbone, a structure that is effective for heat transfer.

The phase-change microcapsule is a spherical phase-change material with a core/shell structure and a phase-change temperature of 37-45 ℃, and the D50 is 1-20 mu m, preferably 10-20 mu m. When the phase-change microcapsule reaches the phase-change temperature, absorbing a part of heat through phase-change heat absorption; in addition, the method can play a role in improving the mechanical property of the system, and has little influence on the heat conductivity coefficient of the composite material. The shell material of the phase-change microcapsule is a composite polymer material, and the core material is paraffin. When the temperature reaches the phase transition temperature, the paraffin of the inner shell material absorbs heat and then softens and deforms, but the shell material can keep the spherical shell structure, so that the permanent solid state of the phase transition material is realized; the device has the characteristics of high heat storage capacity, effective alleviation of equipment heating efficiency, elimination of heating peaks and prolongation of temperature control time; in addition, deformation does not occur during phase transition.

The inhibitor is selected from one or more of ethynyl cyclohexanol, 3-methyl-1-dodecyn-3-ol and 3, 5-dimethyl-1-ethynyl-3-ol.

The platinum catalyst is in powder form or silicone oil form, wherein the platinum content is 1000-8000ppm.

The preparation method of the high-heat-conductivity wave-absorbing rubber sheet comprises the following steps: adding vinyl silicone oil, carbonyl iron, silicon carbide, phase-change microcapsules, diamond and a coupling agent into a double planetary mixer, stirring and mixing uniformly at high temperature, cooling the materials, adding a cross-linking agent, an inhibitor and a platinum catalyst into the double planetary mixer, stirring and mixing uniformly again, and finally obtaining the high-heat-conductivity wave-absorbing rubber sheet after vacuum defoamation, calendaring into sheets and hot air vulcanization.

The high temperature stirring and mixing temperature is 160-180 ℃, and the stirring time is 30-60min.

The temperature of the re-stirring and mixing is not higher than 30 ℃, and the stirring time is 30-60min.

The temperature of the vacuum defoaming is not higher than 40 ℃ and the time is 30-60min.

The temperature of the rolled sheet is 10-60 ℃ and the thickness is 0.5-10mm.

The temperature of the hot air vulcanization is 100-130 ℃ and the time is 10-30min.

Compared with the prior art, the invention has the following beneficial effects:

the invention uses magnetic material flaky carbonyl iron, silicon carbide and diamond to compound, improves the wave absorbing efficiency through the synergistic effect of the iron-based wave absorbing filler and the carbon-based wave absorbing filler, solves the problems of poor wave absorbing performance and narrow wave absorbing frequency of the rubber wave absorbing plate at low frequency, achieves good heat conduction wave absorbing effect, and the maximum wave absorbing rate of the prepared rubber wave absorbing plate (thickness of 2.0 mm) at the wave band of 3-20 GHz can reach-20 dB;

the invention uses the carbon heat conduction material diamond, silicon carbide and phase change microcapsule to compound, replaces the traditional aluminum oxide and aluminum nitride, has excellent heat conduction performance, has good chemical stability, and solves the problems of low heat conduction coefficient of aluminum oxide and poor stability of aluminum nitride; the phase-change microcapsule material can still keep solid after being heated due to the specificity of the core-shell structure, and the internal paraffin is converted into liquid from solid, so that the heat absorption process is realized, and the thermal resistance of the heat-conducting rubber sheet is further reduced, so that the heat can be conducted out as soon as possible. Different from the traditional phase-change heat-conducting material, the phase-change heat-conducting material solves the problems of deformation and even exudation during phase change under the condition of retaining the heat absorption characteristic of the phase change.

Through selecting different kinds of coupling agents, selecting proper addition amount according to the particle sizes and the shapes of different powder, adding the powder, vinyl silicone oil and the coupling agents into a stirrer, and carrying out secondary treatment on the powder through high-temperature mixing. The problem of the dispersion of different heat conduction wave absorbing powder when carrying out the compound and mixing is solved, the viscosity of material when greatly having reduced processing has improved the effectiveness of the even mutual misce bene of different materials.

By compounding vinyl silicone oil and/or hydrogen-containing silicone oil of different types, the problem of molding vulcanization is solved, and the problem of gasket cracking caused by partial crosslinking is improved.

Detailed Description

The present invention is described in detail below with reference to specific embodiments, and it should be noted that the following embodiments are only for further description of the present invention and should not be construed as limiting the scope of the present invention, and some insubstantial modifications and adjustments of the present invention by those skilled in the art from the present disclosure are still within the scope of the present invention.

The amounts of the respective raw materials in the examples and comparative examples were in parts by mass.

Reference standard for performance test:

rubber test: GB/T6038-2006 rubber test sizing material compounding, mixing and vulcanizing equipment and operation procedure.

Mechanical properties: measurement of tensile stress Strain Properties of GB/T528-2009 vulcanized rubber or thermoplastic rubber.

Thermal conductivity: GB/T29313-2012 test method for heat conduction performance of electrical insulation materials.

Wave absorbing performance: a GJB 2038A-2011 radar absorbing material reflectivity testing method.

Example 1

The formulation is shown in Table 1.

The vinyl silicone oil is vinyl end-capped polydimethylsiloxane, the viscosity is 100mpa.s, and the vinyl content is 0.5%; the carbonyl iron is lamellar carbonyl iron, and the D50 particle size is 2 mu m; the silicon carbide has a spherical structure, and the D50 particle size is 30 mu m; the phase-change microcapsule is a spherical phase-change material with a core/shell structure, the D50 particle size is 10 mu m, the phase-change temperature is 45 ℃ (PCM-45 (45 ℃); the diamond is in an irregular polyhedron shape, and the D50 particle size is 100 mu m; the cross-linking agent is hydrogen-terminated polydimethylsiloxane, the viscosity is 10mpa.s, and the active hydrogen content is 0.3%; the inhibitor is ethynyl cyclohexanol; the platinum catalyst was 3000ppm silicone oil type (PT-3000 silicone oil type, zongjun chemical Co., ltd.).

The preparation process conditions are as follows: according to the mass ratio of each component in the embodiment 1 in the table 1, firstly, vinyl silicone oil, carbonyl iron, silicon carbide, phase-change microcapsules, diamond and a coupling agent are mixed in a double planetary mixer for 40min at a high temperature of 160 ℃, and after the materials are cooled to room temperature, other raw materials are added and mixed for 40min, so that a uniformly dispersed mixture is obtained. The premixed sizing mixture was defoamed in vacuo at room temperature for 40min, and was calendered into a sheet by means of a calendering apparatus at a calendering temperature of 30℃and a thickness of 2mm. Transferring the rolled film to a hot drying tunnel, wherein the temperature of hot air is 120 ℃, and the time is 20min, so that the high-heat-conductivity wave-absorbing rubber sheet is obtained.

Example 2

The formulation is shown in Table 1.

The vinyl silicone oil is vinyl end-capped polydimethylsiloxane, the viscosity is 100mpa.s, and the vinyl content is 0.5%; the carbonyl iron is lamellar carbonyl iron, and the D50 particle size is 4 mu m; the silicon carbide has a spherical structure, and the D50 particle size is 40 mu m; the phase-change microcapsule is a spherical phase-change material with a core/shell structure, the D50 particle size is 10 mu m, the phase-change temperature is 45 ℃ (PCM-45 (45 ℃); the diamond is in an irregular polyhedron shape, and the D50 particle size is 100 mu m; the cross-linking agent is hydrogen-terminated polydimethylsiloxane, the viscosity is 10mpa.s, and the active hydrogen content is 0.3%; the inhibitor is ethynyl cyclohexanol; the platinum catalyst was 3000ppm silicone oil type (PT-3000 silicone oil type, zongjun chemical Co., ltd.).

The preparation process conditions are as follows: according to the mass ratio of each component in the embodiment 2 in the table 1, firstly, vinyl silicone oil, carbonyl iron, silicon carbide, phase-change microcapsules, diamond and a coupling agent are mixed in a double planetary mixer for 40min at a high temperature of 160 ℃, and after the materials are cooled to room temperature, other raw materials are added and mixed for 40min, so that a uniformly dispersed mixture is obtained. The premixed sizing mixture was defoamed in vacuo at room temperature for 40min, and was calendered into a sheet by means of a calendering apparatus at a calendering temperature of 30℃and a thickness of 2mm. Transferring the rolled film to a hot drying tunnel, wherein the temperature of hot air is 120 ℃, and the time is 20min, so that the high-heat-conductivity wave-absorbing rubber sheet is obtained.

Example 3

The formulation is shown in Table 1.

The vinyl silicone oil is vinyl end-capped polydimethylsiloxane, the viscosity is 100mpa.s, and the vinyl content is 0.3%; the carbonyl iron is lamellar carbonyl iron, and the D50 particle size is 4 mu m; the silicon carbide has a spherical structure, and the D50 particle size is 40 mu m; the phase-change microcapsule is a spherical phase-change material with a core/shell structure, the D50 particle size is 10 mu m, the phase-change temperature is 45 ℃ (PCM-45 (45 ℃); the diamond is in an irregular polyhedron shape, and the D50 particle size is 130 mu m; the cross-linking agent is hydrogen-terminated polydimethylsiloxane, the viscosity is 15mpa.s, and the active hydrogen content is 0.3%; the inhibitor is ethynyl cyclohexanol; the platinum catalyst was 3000ppm silicone oil type (PT-3000 silicone oil type, zongjun chemical Co., ltd.).

The preparation process conditions are as follows: according to the mass ratio of each component in the embodiment 3 in the table 1, firstly, vinyl silicone oil, carbonyl iron, silicon carbide, phase change microcapsules, diamond and a coupling agent are mixed in a double planetary mixer for 40min at a high temperature of 180 ℃, and after the materials are cooled to room temperature, other raw materials are added and mixed for 40min, so that a uniformly dispersed mixture is obtained. The premixed sizing mixture was defoamed in vacuo at room temperature for 40min, and was calendered into a sheet by means of a calendering apparatus at 60℃and a thickness of 2mm. Transferring the rolled film to a hot drying tunnel, wherein the temperature of hot air is 120 ℃, and the time is 20min, so that the high-heat-conductivity wave-absorbing rubber sheet is obtained.

Example 4

The formulation is shown in Table 1.

The vinyl silicone oil is vinyl end-capped polydimethylsiloxane, the viscosity is 100mpa.s, and the vinyl content is 0.3%; the carbonyl iron is lamellar carbonyl iron, and the D50 particle size is 8 mu m; the silicon carbide has a spherical structure, and the D50 particle size is 60 mu m; the phase-change microcapsule is a spherical phase-change material with a core/shell structure, the D50 particle size is 10 mu m, the phase-change temperature is 45 ℃ (PCM-45 (45 ℃); the diamond is in an irregular polyhedron shape, and the D50 particle size is 130 mu m; the cross-linking agent is hydrogen-terminated polydimethylsiloxane, the viscosity is 15mpa.s, and the active hydrogen content is 0.3%; the inhibitor is ethynyl cyclohexanol; the platinum catalyst was 3000ppm silicone oil type (PT-3000 silicone oil type, zongjun chemical Co., ltd.).

The preparation process conditions are as follows: according to the mass ratio of each component in the embodiment 4 in the table 1, firstly, vinyl silicone oil, carbonyl iron, silicon carbide, phase change microcapsules, diamond and a coupling agent are mixed in a double planetary mixer for 40min at a high temperature of 180 ℃, and after the materials are cooled to room temperature, other raw materials are added and mixed for 40min, so that a uniformly dispersed mixture is obtained. The premixed sizing mixture was defoamed in vacuo at room temperature for 40min, and was calendered into a sheet by means of a calendering apparatus at 60℃and a thickness of 2mm. Transferring the rolled film to a hot drying tunnel, wherein the temperature of hot air is 120 ℃, and the time is 20min, so that the high-heat-conductivity wave-absorbing rubber sheet is obtained.

Comparative example 1

The formulation is shown in Table 1.

Compared to example 1, the comparative example has no diamond thermally conductive filler;

the vinyl silicone oil is vinyl end-capped polydimethylsiloxane, the viscosity is 100mpa.s, and the vinyl content is 0.5%; the carbonyl iron is lamellar carbonyl iron, and the D50 particle size is 2 mu m; the silicon carbide has a spherical structure, and the D50 particle size is 40 mu m; the phase-change microcapsule is a spherical phase-change material with a core/shell structure, the D50 particle size is 10 mu m, the phase-change temperature is 45 ℃ (PCM-45 (45 ℃); the alumina has a spherical structure, and the D50 particle size is 100 mu m; the cross-linking agent is hydrogen-terminated polydimethylsiloxane, the viscosity is 10mpa.s, and the active hydrogen content is 0.3%; the inhibitor is ethynyl cyclohexanol; the platinum catalyst was 3000ppm silicone oil type (PT-3000 silicone oil type, zongjun chemical Co., ltd.).

The preparation process conditions are as follows: according to the mass ratio of each component of comparative example 1 in Table 1, vinyl silicone oil, aluminum oxide, carbonyl iron, silicon carbide, phase-change microcapsules and a coupling agent are firstly mixed in a double planetary mixer for 40min at a high temperature of 160 ℃, and after the materials are cooled to room temperature, other raw materials are added and mixed for 40min, so as to obtain a uniformly dispersed mixture. The premixed sizing mixture was defoamed in vacuo at room temperature for 40min, and was calendered into a sheet by means of a calendering apparatus at a calendering temperature of 30℃and a thickness of 2mm. Transferring the rolled film to a hot drying tunnel, wherein the temperature of hot air is 120 ℃, and the time is 20min, so that the heat-conducting wave-absorbing rubber sheet is obtained.

Comparative example 2

The formulation is shown in Table 1.

Comparative example 2 was free of silicon carbide, phase change microcapsules, diamond thermally conductive filler, as compared to example 4;

the vinyl silicone oil is vinyl end-capped polydimethylsiloxane, the viscosity is 100mpa.s, and the vinyl content is 0.3%; the carbonyl iron is lamellar carbonyl iron, and the D50 particle size is 8 mu m; the alumina has a spherical structure, and the D50 particle size is 100 mu m; the cross-linking agent is hydrogen-terminated polydimethylsiloxane, the viscosity is 15mpa.s, and the active hydrogen content is 0.3%; the inhibitor is ethynyl cyclohexanol; the platinum catalyst was 3000ppm silicone oil type (PT-3000 silicone oil type, zongjun chemical Co., ltd.).

The preparation process conditions are as follows: according to the mass ratio of each component of comparative example 2 in Table 1, vinyl silicone oil, aluminum oxide, carbonyl iron and a coupling agent are firstly mixed in a double planetary mixer for 40min at a high temperature of 180 ℃, and after the materials are cooled to room temperature, other raw materials are added and mixed for 40min, so that a uniformly dispersed mixture is obtained. The premixed sizing mixture was defoamed in vacuo at room temperature for 40min, and was calendered into a sheet by means of a calendering apparatus at 60℃and a thickness of 2mm. Transferring the rolled film to a hot drying tunnel, wherein the temperature of hot air is 120 ℃, and the time is 20min, so that the heat-conducting wave-absorbing rubber sheet is obtained.

Comparative example 3

The formulation is shown in Table 1.

In comparison with example 3, comparative example 3 has no phase change microcapsule heat conductive filler;

the vinyl silicone oil is vinyl end-capped polydimethylsiloxane, the viscosity is 100mpa.s, and the vinyl content is 0.3%; the carbonyl iron is lamellar carbonyl iron, and the D50 particle size is 4 mu m; the silicon carbide has a spherical structure, and the D50 particle size is 40 mu m; the diamond is in an irregular polyhedron shape, and the D50 particle size is 130 mu m; the cross-linking agent is hydrogen-terminated polydimethylsiloxane, the viscosity is 15mpa.s, and the active hydrogen content is 0.3%; the inhibitor is ethynyl cyclohexanol; the platinum catalyst was 3000ppm silicone oil type (PT-3000 silicone oil type, zongjun chemical Co., ltd.).

The preparation process conditions are as follows: according to the mass ratio of each component of the comparative example 3 in the table 1, firstly, vinyl silicone oil, carbonyl iron, silicon carbide, diamond and a coupling agent are mixed in a double planetary mixer for 40min at a high temperature of 180 ℃, and after the materials are cooled to room temperature, other raw materials are added and mixed for 40min, so that a uniformly dispersed mixture is obtained. The premixed sizing mixture was defoamed in vacuo at room temperature for 40min, and was calendered into a sheet by means of a calendering apparatus at 60℃and a thickness of 2mm. Transferring the rolled film to a hot drying tunnel, wherein the temperature of hot air is 120 ℃, and the time is 20min, so that the heat-conducting wave-absorbing rubber sheet is obtained.

Table 1 formulations (in parts by weight) of examples 1-4 and comparative examples 1-3

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The heat conductive and wave absorbing rubber sheets prepared in examples 1 to 4 and comparative examples 1 to 3 were tested for mechanical properties, wave absorbing properties and heat conductive properties, and the test results are shown in Table 2.

TABLE 2 results of sheet Performance test for examples 1-4 and comparative examples 1-3

As can be seen from Table 2, the thermal conductivity of comparative example 3 was 5.7W/mK, and the thermal conductivity of examples 1-4 were all greater than 4W/mK, which are significantly better than the thermal conductivities of comparative examples 1 and 2 without diamond added, indicating that the thermal conductivities of the diamond filled sheets are significantly better than the thermal conductivities of the alumina filled sheets.

Compared with example 1, the maximum wave-absorbing rate of example 1 is-23 dB, and the maximum wave-absorbing rate of comparative example 1 is-15 dB, which shows that the addition of diamond significantly improves the wave-absorbing effect and has excellent synergistic wave-absorbing effect.

In comparison with example 4, comparative example 2 was free of diamond, phase-change microcapsules and silicon carbide heat conductive filler, and from the results of the wave-absorbing performance test, the wave-absorbing center frequency of example 4 was about 4.5GHz and was in the C-band (4 to 8 GHz). The absorption center frequency of comparative example 2 was about 6.3GHz, and the maximum absorption was-19 dB in the C-band (4-8 GHz). It is explained that the wave-absorbing center frequency was shifted to a low frequency by about 2GHz after the carbon-based wave-absorbing filler was introduced. In addition, as can be seen from examples 1 to 4, as the amount of carbonyl iron added gradually increases, the center frequency of the heat conductive wave-absorbing rubber sheet moves toward lower frequency, the wave-absorbing center frequency of the sheet of example 1 is around 8.4GHz, at X-band (8 to 12 GHz), the wave-absorbing center frequency of the sheet of example 2 is 7.9GHz, at C-band (4 to 8 GHz), the wave-absorbing center frequency of the sheet of example 3 is 7.3GHz, at C-band (4 to 8 GHz), the wave-absorbing center frequency of the sheet of example 4 is 4.5GHz, at C-band (4 to 8 GHz), and the maximum wave-absorbing rate is less than-20 dB, which shows excellent wave-absorbing effect and synergistic wave-absorbing effect, and shows that the wave-absorbing center frequency range can be adjusted by adjusting the amount of carbonyl iron added.

Compared with the example 3, the comparative example 3 is free of phase change microcapsules, and from the mechanical property test result, the tensile strength of the comparative example 3 is 0.12MPa and the elongation at break is 42%; the tensile strength of example 3 was 0.23MPa and the elongation at break was 69%; the addition of the phase-change microcapsule can improve the mechanical property of the sheet. In addition, as can be seen from examples 1-4, the tensile strength is greater than 0.19MPa, the elongation at break is greater than 61%, the mechanical properties of comparative examples 1 and 2 are obviously better than those of comparative examples 2, and the mechanical properties of example 2 are optimal, which indicates that the mechanical properties of the sheet can be further improved by properly increasing the filling amount of the phase-change microcapsules.

Claims (10)

1. The high-heat-conductivity wave-absorbing rubber sheet is characterized by comprising, by mass, 100 parts of vinyl silicone oil, 200-800 parts of carbonyl iron, preferably 300-500 parts of silicon carbide, 100-300 parts of silicon carbide, preferably 100-200 parts of phase-change microcapsules, 100-300 parts of diamond, 400-1000 parts of diamond, preferably 500-800 parts of cross-linking agent, 2-8 parts of cross-linking agent, preferably 3-4.5 parts of inhibitor, 0.1-0.8 part of inhibitor, preferably 0.3-0.4 part of platinum catalyst, 0.1-0.8 part of platinum catalyst, preferably 0.5-0.6 part of coupling agent, and 1-5 parts of coupling agent, preferably 3-4 parts of coupling agent.

2. The high-heat-conductivity wave-absorbing rubber sheet according to claim 1, wherein the coupling agent is one or more of silane coupling agent, stearic acid and unsaturated organic acid; the inhibitor is selected from one or more of ethynyl cyclohexanol, 3-methyl-1-dodecyn-3-ol and 3, 5-dimethyl-1-ethynyl-3-ol.

3. The high-heat-conductivity wave-absorbing rubber sheet according to claim 1, wherein the vinyl silicone oil is one or more of vinyl-terminated polydimethylsiloxane, terminal vinyl silicone oil, terminal methyl vinyl silicone oil and partial terminated vinyl silicone oil.

4. The high-heat-conductivity wave-absorbing rubber sheet according to claim 1, wherein the cross-linking agent is one or more of hydrogen-terminated polydimethylsiloxane, hydrogen-terminated polydimethylsiloxane and partially hydrogen-terminated polydimethylsiloxane.

5. The high thermal conductivity wave absorbing rubber sheet according to claim 1, wherein the phase change microcapsules are spherical phase change materials with core/shell structures with phase change temperature of 37-45 ℃ and D50 of 1-20 μm, preferably 10-20 μm.

6. The method for preparing the high-thermal-conductivity wave-absorbing rubber sheet according to any one of claims 1 to 5, wherein the specific operation of the preparation method is as follows: adding vinyl silicone oil, carbonyl iron, silicon carbide, phase-change microcapsules, diamond and a coupling agent into a double planetary mixer, stirring and mixing uniformly at high temperature, cooling the materials, adding a cross-linking agent, an inhibitor and a platinum catalyst into the double planetary mixer, stirring and mixing uniformly again, and finally obtaining the high-heat-conductivity wave-absorbing rubber sheet after vacuum defoamation, calendaring into sheets and hot air vulcanization.

7. The method according to claim 6, wherein the high temperature stirring and mixing is performed at 160-180deg.C for 30-60min.

8. The method according to claim 6, wherein the vacuum degassing is carried out at a temperature of not higher than 40℃for 30 to 60 minutes.

9. The method according to claim 6, wherein the temperature of the rolled sheet is 10-60 ℃ and the thickness is 0.5-10mm.

10. The method according to claim 6, wherein the hot air vulcanization is carried out at a temperature of 100 to 130 ℃ for a time of 10 to 30 minutes.