CN114316603A - Orientable low-dielectric heat-conducting wave-absorbing gel and preparation method and application thereof - Google Patents

Abstract

The invention provides orientable low-dielectric heat-conducting wave-absorbing gel and a preparation method and application thereof, and relates to the technical field of heat-conducting wave-absorbing materials. The invention comprises an agent A and an agent B; wherein, the agent A is mainly prepared from the following raw materials: 20-100 parts of vinyl-containing polysiloxane, 100-600 parts of heat-conducting filler, 100-600 parts of wave absorbing agent, 0.5-5 parts of coupling agent and 0.5-5 parts of catalyst; the agent B is mainly prepared from the following raw materials: 10-100 parts of vinyl-containing polysiloxane, 1-10 parts of hydrosilicyl-containing polysiloxane, 100-600 parts of heat-conducting filler, 100-600 parts of wave absorbing agent, 0.5-5 parts of coupling agent and 0.1-10 parts of inhibitor. The invention solves the technical problem that the wave-absorbing gel cannot give consideration to both high heat conductivity coefficient and high wave-absorbing performance, and achieves the technical effects of better giving consideration to both high heat conductivity coefficient and high wave-absorbing performance and having low dielectric constant.

Description

Orientable low-dielectric heat-conducting wave-absorbing gel and preparation method and application thereof

Technical Field

The invention relates to the technical field of heat-conducting wave-absorbing materials, in particular to orientable low-dielectric heat-conducting wave-absorbing gel and a preparation method and application thereof.

Background

The rapid development of information technology has led to the increasingly smaller and more integrated electronic devices. However, heat dissipation problems and electromagnetic interference on electronic devices can affect the proper operation of the devices. Therefore, in order to solve the heat dissipation problem and the electromagnetic interference, the heat-conducting wave-absorbing material not only needs to have good wave-absorbing performance, but also needs to have excellent heat-conducting performance. Meanwhile, in the 5G field, there is an increasing demand for low dielectric constant materials.

At present, the heat-conducting wave-absorbing gel material sold in the market mainly comprises a heat-conducting agent, a wave-absorbing agent and resin, and the heat-conducting coefficient and the wave-absorbing performance are generally improved by increasing the filling amount of the heat-conducting agent and the wave-absorbing agent. However, higher contents of the heat-conducting agent and the wave-absorbing agent also cause problems such as an increase in viscosity of the material, difficulty in molding, and the like. Therefore, in the heat-conducting wave-absorbing gel material, the filling amount of the heat-conducting agent and the wave-absorbing agent is limited, so that the heat-conducting wave-absorbing gel with high heat conductivity, better wave-absorbing performance and low dielectric constant is difficult to obtain.

In view of the above, the present invention is particularly proposed.

Disclosure of Invention

One of the purposes of the invention is to provide orientable low-dielectric heat-conduction wave-absorbing gel which can better give consideration to high heat conductivity coefficient, high wave-absorbing performance and low dielectric constant.

The second purpose of the invention is to provide a preparation method of orientable low-dielectric heat-conducting wave-absorbing gel.

The invention also aims to provide application of the orientable low-dielectric heat-conducting wave-absorbing gel in electronic equipment.

In order to achieve the above purpose of the present invention, the following technical solutions are adopted:

in a first aspect, the invention provides an orientable low dielectric heat-conducting wave-absorbing gel, which comprises the following components:

an agent A and an agent B;

wherein the mass ratio of the agent A to the agent B is 1: (0.1 to 10);

the agent A is mainly prepared from the following raw materials in parts by weight:

20-100 parts of first vinyl-containing polysiloxane, 100-600 parts of first heat-conducting filler, 100-600 parts of first wave absorbing agent, 0.5-5 parts of first coupling agent and 0.5-5 parts of catalyst;

the agent B is mainly prepared from the following raw materials in parts by weight:

10-100 parts of second vinyl-containing polysiloxane, 1-10 parts of hydrosilicyl-containing polysiloxane, 100-600 parts of second heat-conducting filler, 100-600 parts of second wave absorbing agent, 0.5-5 parts of second coupling agent and 0.1-10 parts of inhibitor.

Further, the viscosity of the first vinyl-containing polysiloxane and the viscosity of the second vinyl-containing polysiloxane are both independently 20 to 20000 mPa.s;

preferably, the molecule of the silylhydride-containing polysiloxane contains at least two silylhydride groups;

preferably, the hydrosilation-containing polysiloxane contains 0.05-1.6% of hydrogen.

Further, the first and second thermally conductive fillers each independently include at least one of aluminum oxide, aluminum hydroxide, aluminum nitride, boron nitride, silicon carbide, zinc oxide, diamond, magnesium oxide, magnesium hydroxide, carbon fiber, copper powder, silver powder, and aluminum powder;

preferably, the first thermally conductive filler and the second thermally conductive filler each independently comprise at least one of a spherical shape, a spheroidal shape, an onion shape, a massive shape, a flake shape, a fibrous shape, a diamond shape, and an amorphous shape in their micro-topography.

Further, the first wave absorbing agent and the second wave absorbing agent respectively and independently comprise at least one of ferroalloy powder, carbonyl iron powder, iron-silicon-aluminum powder, polycrystalline iron fiber, ferrite, graphite, acetylene black and silicon carbide;

preferably, the first wave absorbing agent and the second wave absorbing agent each independently comprise at least one of a spherical shape, a spheroidal shape, an onion shape, a massive shape, a flake shape, a fibrous shape, a diamond shape, and an amorphous shape;

preferably, the first wave absorber and the second wave absorber each independently have a micro-topography that is at least one of flake-like and fibrous;

preferably, the ratio of the diameter to the thickness of the flaky wave absorbing agent is 10-100;

preferably, the ratio of the length to the diameter of the fibrous wave absorbing agent is 5-500;

preferably, the particle size range of the first wave absorbing agent and the particle size range of the second wave absorbing agent are both independently 1-300 microns.

Further, the first wave absorbing agent and the second wave absorbing agent each independently comprise a surface-treated wave absorbing agent;

preferably, the surface treatment comprises at least one of atomization spraying, magnetron sputtering coating and chemical vapor deposition;

preferably, the surface-treated treating agent includes a silane coupling agent and silica.

Further, each of the first coupling agent and the second coupling agent independently includes at least one of methyltrimethoxysilane, vinyltrimethoxysilane, hexyltrimethoxysilane, heptyltrimethoxysilane, octyltrimethoxysilane, dodecyltrimethoxysilane, hexadecyltrimethoxysilane, aluminate, and titanate.

Further, the catalyst in the agent a comprises a platinum-gold complex;

preferably, the inhibitor in agent B comprises at least one of diallyl maleate, 2-methyl-3-butyn-2-ol, N-dimethylacrylamide, ethynylcyclohexanol, 1, 3, 5, 7-tetravinyl-1, 3, 5, 7-tetramethylcyclotetrasiloxane;

preferably, the dielectric constant of the orientable low dielectric, thermally conductive, and wave absorbing gel is less than 5, preferably less than 3.

In a second aspect, the invention provides a preparation method of the orientable low-dielectric heat-conducting wave-absorbing gel, which comprises the following steps:

mixing the raw materials of the agent A to obtain the agent A;

mixing the raw materials of the agent B to obtain the agent B;

mixing the agent A and the agent B to obtain a mixture;

and carrying out directional arrangement on the first wave absorbing agent and/or the second wave absorbing agent in the mixture to obtain the retrievable heat-conducting wave-absorbing gel.

Further, the directional arrangement method comprises the steps of carrying out directional arrangement by using a mould;

preferably, the directional arrangement of the first wave absorber and/or the second wave absorber comprises the following steps:

the mixture enters through the inlet end of the mould and then exits through the outlet end of the mould to obtain the retrievable heat-conducting wave-absorbing gel;

wherein the area of the inlet end of the mould is greater than the area of the outlet end;

preferably, the shape of the mould comprises a prismoid shape;

preferably, the mold is a quadrangular frustum pyramid shaped mold;

preferably, the long side of the first bottom surface of the quadrangular frustum pyramid shaped mold is greater than or equal to 0.1mm, the short side of the first bottom surface is 0.05-0.5 mm, the long side of the second bottom surface parallel to the first bottom surface is greater than the long side of the first bottom surface, and the short side of the second bottom surface parallel to the first bottom surface is greater than the short side of the first bottom surface.

In a third aspect, the invention provides an application of the orientable low-dielectric heat-conducting wave-absorbing gel in electronic equipment.

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

the orientable low-dielectric heat-conduction wave-absorbing gel provided by the invention has the advantages that the components and the parts by weight thereof are cooperatively matched, the high heat conductivity coefficient and the high wave-absorbing performance can be better considered, the low dielectric property is realized, the heat conductivity coefficient is more than 8W/(m.K), the shielding effectiveness is more than 20dB, and the dielectric constant is less than 5.

The preparation method of the orientable low-dielectric heat-conduction wave-absorbing gel provided by the invention improves the wave-absorbing performance by directionally arranging the wave-absorbing agent, and has the advantages of simple process, easy operation and high excellent rate.

The orientable low-dielectric heat-conducting wave-absorbing gel provided by the invention can be applied to electronic equipment, and can better solve the problems of heat dissipation and electromagnetic interference.

Drawings

In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings used in the description of the embodiments or the prior art will be briefly described below, and it is obvious that the drawings in the following description are some embodiments of the present invention, and other drawings can be obtained by those skilled in the art without creative efforts.

FIG. 1 is a schematic structural view of a quadrangular frustum pyramid shaped mold according to an embodiment of the present invention;

FIG. 2 is a schematic structural diagram of a prismoid-like mold according to an embodiment of the present invention;

FIG. 3 is a schematic structural diagram of a stepped mold according to an embodiment of the present invention;

FIG. 4 is a schematic structural diagram of a ladder-like mold according to an embodiment of the present invention;

fig. 5 is a schematic structural diagram of a mold with a spring plate according to an embodiment of the present invention;

fig. 6 is a schematic view of an orientation structure of a heat-conducting wave-absorbing gel according to an embodiment of the present invention.

Detailed Description

The technical solutions of the present invention will be described clearly and completely with reference to the following embodiments, and it should be understood that the described embodiments are some, but not all, embodiments of the present invention. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present invention.

According to a first aspect of the present invention there is provided a thermally conductive, microwave absorbing gel comprising the following components:

an agent A and an agent B;

wherein the mass ratio of the agent A to the agent B is 1: (0.1 to 10);

the agent A is mainly prepared from the following raw materials in parts by weight:

20-100 parts of first vinyl-containing polysiloxane, 100-600 parts of first heat-conducting filler, 100-600 parts of first wave absorbing agent, 0.5-5 parts of first coupling agent and 0.5-5 parts of catalyst;

the agent B is mainly prepared from the following raw materials in parts by weight:

10-100 parts of second vinyl-containing polysiloxane, 1-10 parts of hydrosilicyl-containing polysiloxane, 100-600 parts of second heat-conducting filler, 100-600 parts of second wave absorbing agent, 0.5-5 parts of second coupling agent and 0.1-10 parts of inhibitor.

In the present invention, a typical but non-limiting mass ratio of the agent a and the agent B is, for example, 1: 0.5, 1: 1. 1: 1.5, 1: 2. 1: 2.5, 1: 3. 1: 3.5, 1: 4. 1: 4.5, 1: 5. 1: 5.5, 1: 6. 1: 6.5, 1: 7. 1: 7.5, 1: 8. 1: 8.5, 1: 9. 1: 9.5, 1: 10.

typical but non-limiting parts by weight of the first vinyl-containing polysiloxane in the agent a raw material of the present invention are, for example, 20 parts, 40 parts, 60 parts, 80 parts, 100 parts; typical but non-limiting parts by weight of the first thermally conductive filler are, for example, 100 parts, 200 parts, 300 parts, 400 parts, 500 parts, 600 parts; typical but non-limiting parts by weight of the first wave absorber are, for example, 100 parts, 200 parts, 300 parts, 400 parts, 500 parts, 600 parts; typical but non-limiting parts by weight of the first coupling agent are for example 0.5 parts, 1 part, 2 parts, 3 parts, 4 parts, 5 parts; typical but non-limiting parts by weight of the catalyst are, for example, 0.5 parts, 1 part, 2 parts, 3 parts, 4 parts, 5 parts.

Typical but non-limiting parts by weight of the second vinyl-containing polysiloxane in the agent B raw material of the present invention are, for example, 10 parts, 20 parts, 40 parts, 60 parts, 80 parts, 100 parts; typical but non-limiting parts by weight of the silylhydride-containing polysiloxane are, for example, 1 part, 2 parts, 4 parts, 6 parts, 8 parts, 10 parts; typical but non-limiting parts by weight of the second thermally conductive filler are, for example, 100 parts, 200 parts, 300 parts, 400 parts, 500 parts, 600 parts; typical but non-limiting parts by weight of the second wave absorber are, for example, 100 parts, 200 parts, 300 parts, 400 parts, 500 parts, 600 parts; typical but non-limiting parts by weight of the second coupling agent are for example 0.5 parts, 1 part, 2 parts, 3 parts, 4 parts, 5 parts; typical but non-limiting parts by weight of the inhibitor are, for example, 0.1 part, 0.5 part, 1 part, 2 parts, 3 parts, 4 parts, 5 parts, 6 parts, 7 parts, 8 parts, 9 parts, 10 parts.

In the invention, the components and parts by weight of the heat-conducting wave-absorbing gel can be cooperatively matched, so that the effects of high heat conductivity and high wave-absorbing performance can be achieved, the heat conductivity is greater than 8W/(m.K), and the shielding effectiveness is greater than 20 dB.

In a preferred embodiment, the viscosity of the first vinyl-containing polysiloxane of the present invention is 20 to 20000mpa.s, typical but not limiting viscosities being, for example, 20mpa.s, 200mpa.s, 500mpa.s, 1000mpa.s, 1500mpa.s, 2000mpa.s, 6000mpa.s, 8000mpa.s, 10000mpa.s, 15000mpa.s, 18000mpa.s, 20000 mpa.s; the viscosity of the second vinyl group-containing polysiloxane of the present invention is 20 to 20000 mPas, and typical but not limiting viscosities thereof are, for example, 20 mPas, 200 mPas, 500 mPas, 1000 mPas, 1500 mPas, 2000 mPas, 6000 mPas, 8000 mPas, 10000 mPas, 15000 mPas, 18000 mPas, 20000 mPas.

The polysiloxane containing vinyl is polysiloxane containing one or more vinyl groups on one molecule, and the main chain structure of the polysiloxane can be a straight chain or a branched chain, so that the mechanical property of the heat-conducting wave-absorbing gel can be better improved.

In a preferred embodiment, the silylhydride-containing polysiloxane of the present invention contains at least two silylhydride groups in the molecule. The hydrosilyl-containing polysiloxane of the present invention is a polysiloxane containing two or more hydrosilyl groups in one molecule, and has a hydrogen content of 0.05 to 1.6%, and typical but non-limiting hydrogen contents are, for example, 0.05%, 0.08%, 0.1%, 0.5%, 1%, 1.2%, 1.4%, and 1.6%.

The selected specific polysiloxane containing silicon-hydrogen groups can better improve the mechanical property of the heat-conducting wave-absorbing gel.

In a preferred embodiment, the first thermally conductive filler of the present invention includes, but is not limited to, at least one of aluminum oxide, aluminum hydroxide, aluminum nitride, boron nitride, silicon carbide, zinc oxide, diamond, magnesium oxide, magnesium hydroxide, carbon fiber, copper powder, silver powder, and aluminum powder; the second thermally conductive filler of the present invention includes, but is not limited to, at least one of alumina, aluminum hydroxide, aluminum nitride, boron nitride, silicon carbide, zinc oxide, diamond, magnesium oxide, magnesium hydroxide, carbon fiber, copper powder, silver powder, and aluminum powder; the micro-morphology of the thermally conductive filler of the present invention includes, but is not limited to, at least one of spherical, spheroidal, onion-like, massive, flake-like, fibrous, rhombohedral, and amorphous.

The heat-conducting property of the material is realized by adding the heat-conducting filler with specific types and micro-morphologies.

In a preferred embodiment, the first wave absorbing agent of the present invention includes, but is not limited to, at least one of ferroalloy powder, carbonyl iron powder, ferrosilicon aluminum powder, polycrystalline iron fiber, ferrite, graphite, acetylene black, and silicon carbide; the second wave absorbing agent of the invention includes but is not limited to at least one of ferroalloy powder, carbonyl iron powder, ferrosilicon aluminum powder, polycrystalline iron fiber, ferrite, graphite, acetylene black and silicon carbide; the micro-morphology of the wave absorber of the invention comprises at least one of a sphere, a sphere-like shape, an onion shape, a block shape, a sheet shape, a fiber shape, a diamond shape and an amorphous shape; further preferably, the micro-morphology of the wave absorber of the present invention is at least one of plate-like and fibrous; wherein, the ratio of the diameter to the thickness of the flaky wave absorbing agent is 10-100, and typical but non-limiting ratios thereof are, for example, 10, 20, 30, 40, 50, 60, 70, 80, 90, 100; the ratio of the length to the diameter of the fibrous wave absorber is 5-500, and typical but non-limiting ratios are, for example, 5, 10, 20, 50, 100, 150, 200, 250, 300, 350, 400, 500; the particle size range of the wave absorbing agent is 1-300 microns, and typical but non-limiting particle sizes of the wave absorbing agent are 1 micron, 2 microns, 4 microns, 6 microns, 8 microns, 10 microns, 20 microns, 25 microns, 30 microns, 40 microns, 50 microns, 60 microns, 70 microns, 80 microns, 90 microns, 100 microns, 150 microns, 200 microns, 250 microns and 300 microns.

The wave absorbing agent with a specific type, a specific microscopic morphology and a specific particle size range can improve the wave absorbing performance of the material.

In a preferred embodiment, the first wave absorber and the second wave absorber of the present invention include, but are not limited to, a wave absorber after surface treatment, wherein the surface treatment includes, but is not limited to, at least one of atomized spray, magnetron sputtering coating, and chemical vapor deposition; the surface treatment agent of the present invention includes, but is not limited to, silane coupling agents, silica and the like, which are highly insulating substances.

The surface treatment can reduce the dielectric constant of the wave absorbing agent so as to enhance the wave absorbing effect.

In a preferred embodiment, the first coupling agent of the present invention includes, but is not limited to, at least one of methyltrimethoxysilane, vinyltrimethoxysilane, hexyltrimethoxysilane, heptyltrimethoxysilane, octyltrimethoxysilane, dodecyltrimethoxysilane, hexadecyltrimethoxysilane, aluminate, and titanate; the second coupling agent of the present invention includes, but is not limited to, at least one of methyltrimethoxysilane, vinyltrimethoxysilane, hexyltrimethoxysilane, heptyltrimethoxysilane, octyltrimethoxysilane, dodecyltrimethoxysilane, hexadecyltrimethoxysilane, aluminate, and titanate.

The coupling agent selected by the invention can realize better reaction effect.

In a preferred embodiment, the catalyst in agent a of the invention includes, but is not limited to, platinum complexes.

The catalyst selected by the invention can realize better catalytic effect so as to improve the performance of the material.

In a preferred embodiment, the inhibitor in agent B includes, but is not limited to, at least one of diallyl maleate, 2-methyl-3-butyn-2-ol, N-dimethylacrylamide, ethynylcyclohexanol, 1, 3, 5, 7-tetravinyl-1, 3, 5, 7-tetramethylcyclotetrasiloxane.

The inhibitor selected by the invention can realize better inhibition effect.

The orientable low dielectric, thermally conductive and wave absorbing gel of the present invention has a dielectric constant of less than 5, and more preferably less than 3.

According to a second aspect of the present invention, there is provided a method for preparing the orientable low dielectric thermal conductive wave absorbing gel, comprising the following steps:

mixing the raw materials of the agent A to obtain the agent A;

mixing the raw materials of the agent B to obtain the agent B;

mixing the agent A and the agent B to obtain a mixture;

and then the first wave absorbing agent and/or the second wave absorbing agent in the mixture are directionally arranged to obtain the orientable low-dielectric heat-conducting wave absorbing gel.

The preparation method of the orientable low-dielectric heat-conducting wave-absorbing gel has the characteristics of simplicity and high efficiency. The preparation method improves the wave absorbing performance by directionally arranging the wave absorbing agent.

In a preferred embodiment, the method of alignment of the present invention comprises performing alignment using a mold;

specifically, the directional arrangement of the first wave absorbing agent and/or the second wave absorbing agent comprises the following steps:

the mixture enters through the inlet end of the mould and then exits through the outlet end of the mould to obtain the retrievable heat-conducting wave-absorbing gel;

wherein the area of the inlet end of the mould is larger than the area of the outlet end.

The shape of the mold of the present invention includes, but is not limited to, a frustum pyramid shape, and the mold of the present invention is preferably a frustum pyramid shaped mold, as shown in the frustum pyramid shaped mold of fig. 1, a long side D of a first bottom surface of the frustum pyramid shaped mold of the present invention is 0.1mm or more, a short side H of the first bottom surface is 0.05 to 0.5mm, a long side D of a second bottom surface parallel to the first bottom surface is larger than the long side D of the first bottom surface, a short side H of the second bottom surface parallel to the first bottom surface is larger than the short side H of the first bottom surface, and a slope of the frustum pyramid shaped mold of the present invention is 0.05 or more and 10 or less.

The mixture enters through the second bottom surface of the quadrangular frustum pyramid and then exits through the first bottom surface to obtain the extractable heat-conducting wave-absorbing gel.

The invention realizes the directional arrangement of the wave absorbing agent through the die, improves the wave absorbing performance of the material, and is simple and efficient.

In the present invention, the shape structure of the mold may also be a prismoid-like structure in fig. 2, or a ladder-like structure in fig. 3, or a ladder-like structure in fig. 4.

In the present invention, the structure of the mold may also be the mold structure with the spring plate in fig. 5, wherein the angle of the spring plate is less than 60 °, the spring plate is made of beryllium copper or other metal sheet with elasticity, when the gel touches the spring plate, the spring plate is bent by the acting force, and the material returns to the original shape after passing through the spring plate.

The orientation structure of the heat-conducting wave-absorbing gel of the invention after passing through the die is shown in figure 6.

According to the third aspect of the invention, the application of the above-mentioned retrievable heat-conducting wave-absorbing gel in electronic equipment is provided, so that the heat dissipation problem and electromagnetic interference can be solved well.

The invention is further illustrated by the following examples. The materials in the examples are prepared according to known methods or are directly commercially available, unless otherwise specified.

Example 1

A heat-conductive wave-absorbing gel contains agent A and agent B.

Wherein, the component and the weight portion of the agent A are as follows:

50 parts of vinyl-containing polysiloxane, 500 parts of sheet carbonyl iron powder, 600 parts of aluminum oxide, 0.5 part of octyl trimethoxy silane and 0.5 part of platinum complex;

the viscosity of the vinyl-containing polysiloxane in the agent A is 500 mPa.s;

the flaky carbonyl iron powder in the agent A is flaky carbonyl iron powder with a silicon dioxide film plated on the surface (the film coating method is magnetron sputtering).

The component and the weight portion of the agent B are as follows:

50 parts of vinyl-containing polysiloxane, 5 parts of hydrosilicyl-containing polysiloxane, 500 parts of sheet carbonyl iron powder, 600 parts of aluminum oxide, 0.5 part of octyl trimethoxy silane and 0.5 part of ethynyl cyclohexanol serving as an inhibitor;

the viscosity of the vinyl-containing polysiloxane in the agent B is 500mPa.s, and the hydrogen content of the hydrosilation-containing polysiloxane is 0.3 percent;

the flaky carbonyl iron powder in the agent B is flaky carbonyl iron powder with a silicon dioxide film plated on the surface (the film coating method is magnetron sputtering).

The preparation method of the sensible heat-conducting wave-absorbing gel comprises the following steps:

uniformly mixing the raw materials of the agent A in a heating stirrer (a planetary stirrer) according to the weight part to obtain the agent A;

uniformly mixing the raw materials of the agent B in a heating stirrer (a planetary stirrer) according to the weight part to obtain the agent B;

the agent A and the agent B are mixed according to the mass ratio of 1: 1, uniformly mixing through a mixing pipe to obtain a mixture;

the mixture is passed through a mould, and is directionally arranged to obtain the heat-conducting wave-absorbing gel with orientation property, the mould is a quadrangular frustum pyramid shaped mould as shown in figure 1, H is 0.1mm, H is 2mm, D is 5mm, and D is 10mm, the mixture is fed in from inlet end and then discharged from outlet end according to the arrow.

Example 2

A heat-conductive wave-absorbing gel contains agent A and agent B.

Wherein, the component and the weight portion of the agent A are as follows:

30 parts of polysiloxane containing vinyl, 400 parts of flaky ferrosilicon aluminum powder, 300 parts of aluminum oxide, 0.5 part of methyltrimethoxysilane and 0.5 part of platinum complex;

the viscosity of the vinyl-containing polysiloxane in the agent A was 100 mPas.

The component and the weight portion of the agent B are as follows:

30 parts of polysiloxane containing vinyl, 5 parts of polysiloxane containing hydrosilation, 500 parts of sheet iron-silicon-aluminum powder, 400 parts of aluminum nitride, 0.5 part of methyltrimethoxysilane and 0.3 part of inhibitor ethynylcyclohexanol;

the viscosity of the vinyl-containing polysiloxane in the agent B is 1000mPa.s, and the hydrogen content of the hydrosilation-containing polysiloxane is 0.3%.

The preparation method is the same as example 1, wherein H is 0.2mm, H is 1mm, D is 10mm, and D is 200 mm.

Example 3

A heat-conductive wave-absorbing gel contains agent A and agent B.

Wherein, the component and the weight portion of the agent A are as follows:

50 parts of vinyl-containing polysiloxane, 600 parts of sheet carbonyl iron powder, 300 parts of aluminum nitride, 0.5 part of dodecyl trimethoxy silane and 0.5 part of platinum complex;

the viscosity of the vinyl-containing polysiloxane in the agent A was 300 mPas.

The component and the weight portion of the agent B are as follows:

50 parts of polysiloxane containing vinyl, 5 parts of polysiloxane containing hydrosilation, 600 parts of sheet carbonyl iron powder, 300 parts of aluminum nitride, 0.5 part of dodecyl trimethoxy silane and 0.5 part of inhibitor 2-methyl-3-butyn-2-ol;

the viscosity of the vinyl-containing polysiloxane in the agent B is 100mPa.s, and the hydrogen content of the hydrosilation-containing polysiloxane is 0.2%.

The preparation method is the same as example 1, wherein H is 0.1mm, H is 3mm, D is 20mm, and D is 30mm

Example 4

The difference between the present embodiment and embodiment 1 is that the agent a in the present embodiment is mainly prepared from the following raw materials in parts by weight:

100 parts of vinyl-containing polysiloxane, 200 parts of heat-conducting filler silicon nitride, 300 parts of lamellar wave-absorbing agent acetylene carbon black, 1 part of coupling agent vinyl trimethoxy silane and 1 part of catalyst platinum-gold complex.

The agent B was the same as in example 1.

The preparation method is the same as that of the example 1, and the heat-conducting wave-absorbing gel with orientation is obtained.

Example 5

The difference between the present embodiment and embodiment 1 is that the agent a in the present embodiment is mainly prepared from the following raw materials in parts by weight:

100 parts of vinyl-containing polysiloxane, 600 parts of heat-conducting filler zinc oxide, 600 parts of flake wave-absorbing agent graphite, 2 parts of coupling agent titanate and 2 parts of catalyst platinum complex;

the viscosity of the vinyl-containing polysiloxane in the agent A is 10000 mPa.s.

The agent B was the same as in example 1.

The preparation method is the same as that of the example 1, and the heat-conducting wave-absorbing gel with orientation is obtained.

Example 6

The difference between the embodiment and the embodiment 1 is that the agent B in the embodiment is mainly prepared from the following raw materials in parts by weight:

100 parts of vinyl-containing polysiloxane, 10 parts of hydrosilicon-containing polysiloxane, 600 parts of heat-conducting filler carbon fiber, 600 parts of wave-absorbing agent polycrystalline iron fiber, 2 parts of coupling agent heptyl trimethoxy silane and 2 parts of inhibitor diallyl maleate.

The agent A was the same as in example 1.

The preparation method is the same as that of the example 1, and the heat-conducting wave-absorbing gel with orientation is obtained.

Example 7

The difference between the embodiment and the embodiment 1 is that the agent B in the embodiment is mainly prepared from the following raw materials in parts by weight:

100 parts of vinyl-containing polysiloxane, 10 parts of silylhydride-containing polysiloxane, 300 parts of heat-conducting filler silver powder, 300 parts of flaky wave absorbing agent ferrite, 1 part of coupling agent titanate and 1 part of inhibitor 2-methyl-3-butyne-2-ol;

the viscosity of the vinyl-containing polysiloxane in the agent B was 15000mPa.s, and the hydrogen content of the silylhydride-containing polysiloxane was 1.2%.

The agent A was the same as in example 1.

The preparation method is the same as that of the example 1, and the heat-conducting wave-absorbing gel with orientation is obtained.

Comparative example 1

The difference between the comparative example and the example 1 is that the preparation raw material of the agent A in the comparative example does not contain polysiloxane containing vinyl, the agent B is the same as the agent A in the example 1, the preparation method is the same as the example 1, and the obtained heat-conducting wave-absorbing gel has overlarge viscosity and no fluidity.

Comparative example 2

The difference between the comparative example and the example 1 is that the preparation raw material of the agent A of the comparative example does not contain the polysiloxane containing vinyl, the polysiloxane containing vinyl in the agent A is replaced by the same amount of methyl silicone oil, the agent B is the same as the agent in the example 1, the preparation method is the same as the example 1, and the heat-conducting wave-absorbing gel is obtained and is not solidified.

Comparative example 3

The components and the amounts of the glue A and the glue B of the comparative example are the same as those of the glue 1.

The preparation method of the comparative example comprises the following steps:

uniformly mixing the raw materials of the agent A in a heating stirrer (a planetary stirrer) according to the weight part to obtain the agent A;

uniformly mixing the raw materials of the agent B in a heating stirrer (a planetary stirrer) according to the weight part to obtain the agent B;

the agent A and the agent B are mixed according to the mass ratio of 1: 1, uniformly mixing through a mixing pipe (wave absorbing agents are not arranged in an oriented mode, and products have no oriented effect), and obtaining the heat-conducting wave absorbing gel.

Comparative example 4

The difference between the comparative example and the example 1 is that the dosage of the flaky carbonyl iron in the preparation raw materials of the agent A and the agent B in the comparative example is 20 parts respectively, other components and dosages of the agent A and the agent B are not changed, and the preparation method is the same as the example 1 to obtain the heat-conducting wave-absorbing gel.

Comparative example 5

The difference between the comparative example and the example 1 is that the dosage of the alumina in the preparation raw materials of the agent A and the agent B in the comparative example is respectively 50 parts, the other components and dosages of the agent A and the agent B are not changed, and the preparation method is the same as the example 1 to obtain the heat-conducting wave-absorbing gel.

Comparative example 6

The difference between the comparative example and the example 1 is that the preparation raw material of the agent B in the comparative example does not contain the polysiloxane containing the hydrosil group, the agent A is the same as the agent A in the example 1, the preparation method is the same as the example 1, and the heat-conducting wave-absorbing gel is obtained and is not cured.

Comparative example 7

The difference between the comparative example and the example 1 is that the preparation raw material of the agent B of the comparative example does not contain the polysiloxane containing the silicon-hydrogen group, the polysiloxane containing the silicon-hydrogen group in the agent B is replaced by the same amount of methyl silicone oil, the agent A is the same as the example 1, the preparation method is the same as the example 1, and the heat-conducting wave-absorbing gel is obtained and is not cured.

Test examples

The heat-conducting wave-absorbing gels obtained in examples 1 to 7 and comparative examples 1 to 7 were tested to obtain data on heat conductivity and wave-absorbing performance, as shown in table 1.

The test method of the thermal conductivity coefficient comprises the following steps: ASTM D5470, units W/(m.K);

the wave absorption performance test method comprises the following steps: GJB 5239-.

The dielectric constant test method comprises the following steps: GB T1693-.

TABLE 1

As can be seen from Table 1, compared with the heat-conducting wave-absorbing gel provided in comparative examples 1 to 7, the heat-conducting wave-absorbing gel provided in examples 1 to 7 of the present invention has a heat conductivity greater than 8W/(m.K), a shielding effectiveness greater than 20dB, and a dielectric constant less than 5, and thus the heat-conducting wave-absorbing gel of the present invention has a high heat conductivity, a high wave-absorbing property, and a low dielectric constant.

Finally, it should be noted that: the above embodiments are only used to illustrate the technical solution of the present invention, and not to limit the same; while the invention has been described in detail and with reference to the foregoing embodiments, it will be understood by those skilled in the art that: the technical solutions described in the foregoing embodiments may still be modified, or some or all of the technical features may be equivalently replaced; and the modifications or the substitutions do not make the essence of the corresponding technical solutions depart from the scope of the technical solutions of the embodiments of the present invention.

Claims (10)

1. An orientable low-dielectric heat-conducting wave-absorbing gel is characterized by comprising the following components:

an agent A and an agent B;

wherein the mass ratio of the agent A to the agent B is 1: (0.1 to 10);

the agent A is mainly prepared from the following raw materials in parts by weight:

20-100 parts of first vinyl-containing polysiloxane, 100-600 parts of first heat-conducting filler, 100-600 parts of first wave absorbing agent, 0.5-5 parts of first coupling agent and 0.5-5 parts of catalyst;

the agent B is mainly prepared from the following raw materials in parts by weight:

10-100 parts of second vinyl-containing polysiloxane, 1-10 parts of hydrosilicyl-containing polysiloxane, 100-600 parts of second heat-conducting filler, 100-600 parts of second wave absorbing agent, 0.5-5 parts of second coupling agent and 0.1-10 parts of inhibitor.

2. The orientable low dielectric, thermally conductive and microwave absorbing gel of claim 1, wherein the viscosity of the first vinyl-containing polysiloxane and the viscosity of the second vinyl-containing polysiloxane are each independently 20 to 20000 mpa.s;

preferably, the molecule of the silylhydride-containing polysiloxane contains at least two silylhydride groups;

preferably, the hydrosilation-containing polysiloxane contains 0.05-1.6% of hydrogen.

3. The orientable, low dielectric, thermally conductive, and microwave absorbing gel of claim 1, wherein the first thermally conductive filler and the second thermally conductive filler each independently comprise at least one of alumina, aluminum hydroxide, aluminum nitride, boron nitride, silicon carbide, zinc oxide, diamond, magnesium oxide, magnesium hydroxide, carbon fiber, copper powder, silver powder, and aluminum powder;

preferably, the first thermally conductive filler and the second thermally conductive filler each independently comprise at least one of a spherical shape, a spheroidal shape, an onion shape, a massive shape, a flake shape, a fibrous shape, a diamond shape, and an amorphous shape in their micro-topography.

4. The orientable low dielectric, thermally conductive and microwave absorbing gel of claim 1, wherein the first and second wave absorbers each independently comprise at least one of ferrous alloy powder, carbonyl iron powder, ferrosilicon aluminum powder, polycrystalline iron fibers, ferrite, graphite, acetylene black, and silicon carbide;

preferably, the first wave absorbing agent and the second wave absorbing agent each independently comprise at least one of a spherical shape, a spheroidal shape, an onion shape, a massive shape, a flake shape, a fibrous shape, a diamond shape, and an amorphous shape;

preferably, the first wave absorber and the second wave absorber each independently have a micro-topography that is at least one of flake-like and fibrous;

preferably, the ratio of the diameter to the thickness of the flaky wave absorbing agent is 10-100;

preferably, the ratio of the length to the diameter of the fibrous wave absorbing agent is 5-500;

preferably, the particle size range of the first wave absorbing agent and the particle size range of the second wave absorbing agent are both independently 1-300 microns.

5. The orientable low dielectric, thermally conductive, and microwave absorbing gel of claim 4, wherein the first and second wave absorbers each independently comprise a surface treated wave absorber;

preferably, the surface treatment comprises at least one of atomization spraying, magnetron sputtering coating and chemical vapor deposition;

preferably, the surface-treated treating agent includes a silane coupling agent and silica.

6. The orientable low dielectric, thermally conductive and microwave absorbing gel of claim 1, wherein each of said first and second coupling agents independently comprises at least one of methyltrimethoxysilane, vinyltrimethoxysilane, hexyltrimethoxysilane, heptyltrimethoxysilane, octyltrimethoxysilane, dodecyltrimethoxysilane, hexadecyltrimethoxysilane, aluminate, and titanate.

7. An orientable low dielectric, thermally conductive and microwave absorbing gel according to any of claims 1 to 6 wherein the catalyst in agent A comprises a platinum complex;

preferably, the inhibitor in agent B comprises at least one of diallyl maleate, 2-methyl-3-butyn-2-ol, N-dimethylacrylamide, ethynylcyclohexanol, 1, 3, 5, 7-tetravinyl-1, 3, 5, 7-tetramethylcyclotetrasiloxane;

preferably, the dielectric constant of the orientable low dielectric, thermally conductive, and wave absorbing gel is less than 5, preferably less than 3.

8. A method of preparing an orientable low dielectric, thermally conductive and microwave absorbing gel according to any of claims 1 to 7, comprising the steps of:

mixing the raw materials of the agent A to obtain the agent A;

mixing the raw materials of the agent B to obtain the agent B;

mixing the agent A and the agent B to obtain a mixture;

and carrying out directional arrangement on the first wave absorbing agent and/or the second wave absorbing agent in the mixture to obtain the orientable low-dielectric heat-conducting wave-absorbing gel.

9. The method of manufacturing according to claim 8, wherein the method of alignment comprises performing alignment using a mold;

preferably, the directional arrangement of the first wave absorber and/or the second wave absorber comprises the following steps:

the mixture enters through the inlet end of the mould and then exits through the outlet end of the mould to obtain the retrievable heat-conducting wave-absorbing gel;

wherein the area of the inlet end of the mould is greater than the area of the outlet end;

preferably, the shape of the mould comprises a prismoid shape;

preferably, the mold is a quadrangular frustum pyramid shaped mold;

preferably, the long side of the first bottom surface of the quadrangular frustum pyramid shaped mold is greater than or equal to 0.1mm, the short side of the first bottom surface is 0.05-0.5 mm, the long side of the second bottom surface parallel to the first bottom surface is greater than the long side of the first bottom surface, and the short side of the second bottom surface parallel to the first bottom surface is greater than the short side of the first bottom surface.

10. Use of an orientable low dielectric, thermally conductive and microwave absorbing gel according to any of claims 1 to 7 in an electronic device.

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