CN114957996A - Flexible silicon rubber substrate with high thermal conductivity and preparation method thereof - Google Patents
Flexible silicon rubber substrate with high thermal conductivity and preparation method thereof Download PDFInfo
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Abstract
The invention discloses a flexible silicon rubber substrate with high thermal conductivity, which only consists of addition liquid silicon rubber with low viscosity and a heat-conducting filler, wherein the heat-conducting filler consists of spherical alumina with single particle size or more than one particle size, and the problem of substrate layering when the heat-conducting filler is low in load is solved by adding a thickening agent, the related components are few, the flexible silicon rubber substrate is compounded with the addition liquid silicon rubber with low viscosity and the spherical alumina, the stirring steric hindrance is small, the spherical alumina is uniformly dispersed, and a finished product has high surface quality and uniform heat-conducting property, and the invention also discloses a preparation method of the flexible silicon rubber substrate, the thin and uniform-property isotropic flexible silicon rubber substrate is prepared by combining low-viscosity silicon rubber and the spherical alumina through a gel casting process, has the advantages of simple equipment and high-efficiency continuous production, the prepared flexible silicon rubber substrate has small defects and uniform performance, and can realize large-scale and industrial production.
Description
Technical Field
The invention belongs to the field of heat-conducting rubber composite materials, and particularly relates to a flexible silicon rubber substrate with high heat conductivity and a preparation method thereof.
Background
In recent years, with the development of Micro Electro Mechanical Systems (MEMS), the computing power per unit volume of a computing chip is increasing, so that the performance of the computing chip is severely limited due to heat accumulation, and the efficient preparation of the high thermal conductive electronic packaging material is a key point in the industry.
Highly thermally conductive composite materials can be broadly classified into three categories according to the matrix: metal-based, ceramic-based, polymer-based composite materials.
In a heat conduction mechanism, a metal material mainly based on free electron heat conduction usually has higher heat conduction performance, but has the defects of electric conductivity caused by electron heat conduction, non-corrosion resistance of simple substance metal and the like;
ceramic materials based on phonon conduction have relatively complete crystal lattices and strong chemical bond connection, so the ceramic materials have relatively high heat-conducting performance and can be directly used as a first layer of materials for packaging a chip, but the ceramic materials have high brittleness and are not suitable for relatively complex processing, and the wide application of the ceramic materials is limited;
the polymer material is mainly based on phonon heat conduction, has excellent mechanical property and sealing property, is widely applied in the packaging and connecting process of electronic equipment, but the material is mostly of an amorphous structure and has serious phonon scattering, so the heat conductivity is lower.
The high-thermal-conductivity silicone rubber composite material is one of high-molecular-weight high-thermal-conductivity composite materials, high-viscosity semi-solid high-temperature vulcanized silicone rubber is generally adopted in the production and preparation of the traditional high-thermal-conductivity silicone rubber composite material, a kneading machine or an internal mixer is generally adopted for mixing materials, a heating and pressing mode is generally adopted in a crosslinking mode, the production mode is more suitable for producing small-batch special-shaped parts and is not suitable for large-batch large-scale production, the semi-solid high-temperature vulcanized silicone rubber has high viscosity, mixing difficulty is caused by high stirring steric hindrance, production energy consumption is high, and non-uniform dispersion of heat-conducting fillers is also caused, and the improvement of the thermal conductivity of the material is not facilitated and the uniformity of the heat-conducting performance is kept.
Disclosure of Invention
In view of the problems in the related art, the present invention provides a flexible silicone rubber substrate with high thermal conductivity to overcome the above technical problems in the related art, and also provides a method for preparing the same.
The technical scheme of the invention is realized as follows:
a flexible silicon rubber substrate with high thermal conductivity only consists of addition type liquid silicon rubber with low viscosity and a thermal conductive filler, and is prepared from the following raw materials in parts by weight:
the addition type liquid silicone rubber consists of 100 parts of component A, 10 parts of component B and 0-10 parts of thickening agent;
the heat conducting filler is 50-400 parts and consists of spherical alumina with single grain size or more than one grain size.
Firstly, compared with the traditional production process of the high-thermal-conductivity silicone rubber composite material, the flexible silicone rubber substrate disclosed by the invention is compounded with the addition type liquid silicone rubber and the spherical alumina with lower viscosity, the adopted addition type liquid silicone rubber has the characteristics of low viscosity, self-leveling and environmental protection, the stirring steric hindrance is small when the addition type liquid silicone rubber and the spherical alumina are mixed due to the characteristic of low viscosity, and the spherical alumina is uniformly dispersed, so that the flexible silicone rubber substrate disclosed by the invention has high surface quality and uniform thermal conductivity, the thermal conductivity of the material is effectively improved due to the uniformly dispersed spherical alumina, the flexible silicone rubber substrate disclosed by the invention has a high thermal conductivity range of 0.311-1.163W/(m.K), and the thermal conductivity encapsulation of electronic devices is met.
Secondly, the traditional ceramic casting process needs to add organic or inorganic solvent, plasticizer, dispersant and the like into the slurry, and the green body has the problems of cracking, bending and large shrinkage rate in the casting and drying process. The flexible silicon rubber substrate disclosed by the invention utilizes the rheological characteristics of low viscosity and self-leveling of liquid silicon rubber gel, avoids the process defects of the traditional ceramic tape-casting slurry drying process, does not contain organic solvent, accords with the green environmental protection concept, simultaneously has few related components, is convenient to realize efficient large-scale and batch production or regulate and control the mechanical property, the heat conductivity and the like so as to meet different service conditions, and is particularly suitable for preparing the heat-conducting silicon rubber substrate with low-loading-capacity heat-conducting filler, small thickness and small size and uniformity.
Finally, the invention specially adjusts the component contents of the heat-conducting filler, the liquid silicon rubber and the thickening agent, so that the heat-conducting filler is uniformly dispersed in the liquid silicon rubber and is kept stable in the casting process, and the prepared flexible silicon rubber substrate is prevented from layering.
Preferably, the component A is one or more of dimethyl siloxane, vinyl-terminated dimethyl polysiloxane, a vinyl MQ resin mixture and ethylbenzene;
the component B is one or more of poly (dimethyl siloxane-co-methyl hydrogen siloxane) trimethyl silane, monovinyl end-capped dimethyl (siloxane and polysiloxane) and a vinyl MQ resin mixture.
With the development of the organic silicon industry, the supply viscosity range of the silicon rubber raw material can be from 100-1200000 mPas, the invention adopts 3000-5000 mPas low-viscosity self-leveling liquid silicon rubber as a matrix material, and the prepared slurry can still keep larger viscosity redundancy even under the condition of high filler loading, thereby providing a space for the dispersion of the heat-conducting filler and the defoaming of the casting slurry.
Preferably, the spherical alumina is unmodified spherical alumina, modified spherical alumina or a mixture of the two;
the modified spherical alumina is spherical alumina particles subjected to saturated hydroxyl activation treatment and silane coupling agent surface modification, and the modified spherical alumina and the liquid silicone rubber have better interface bonding capability, so that the flexible silicone rubber substrate disclosed by the invention is prevented from being layered, the density of the flexible silicone rubber substrate disclosed by the invention is improved, and the thermal conductivity is further improved.
Preferably, the heat-conducting filler is formed by mixing one or more than one spherical alumina particles with D50 particle size of 5, 20, 40, 70, 90 and 120 um.
Preferably, the thickener is gas phase SiO 2 One or more of polyvinyl alcohol and polymethyl methacrylate, and the thickener also serves as the reinforcing agent of the present invention.
The preparation method of the flexible silicon rubber substrate comprises the following steps:
(1) drying the spherical alumina as the heat-conducting filler, removing excessive water, and keeping the state consistency of the heat-conducting filler before preparation for later use;
(2) directly taking the component A of the liquid silicone rubber as matrix slurry, or adding a proper amount of thickening agent into the component A of the liquid silicone rubber and uniformly stirring to prepare matrix slurry;
(3) adding the heat-conducting filler treated in the step (1) into the matrix slurry in the step (2) according to a preset weight part, and uniformly mixing;
(4) adding a preset weight part of the component B of the liquid silicone rubber into the slurry prepared in the step (3) to prepare casting slurry;
(5) defoaming the casting slurry prepared in the step (4), so that the density of the casting slurry is improved, and the content of air phase in the casting slurry is reduced, thereby improving the thermal conductivity of the prepared flexible silicon rubber substrate;
(6) casting the casting slurry subjected to defoaming treatment in the step (5) in a casting machine, combining the self-leveling property of liquid silicon rubber with the casting machine to enable the thickness of the prepared flexible thin substrate to be uniform and adjustable, heating and crosslinking the flexible thin substrate by a drying tunnel of the casting machine, and winding the flexible thin substrate after curing to obtain the flexible silicon rubber substrate with high thermal conductivity.
(7) And (4) cutting the coiled material obtained in the step (6) to obtain a finished product, wherein the thickness of the finished product is 100-3000 microns.
The preparation method can improve the dispersion degree and the loading capacity of the spherical alumina in the liquid silicone rubber matrix, thereby improving the thermal conductivity and the stability of the finished flexible silicone rubber substrate, and can also utilize the advantages of the traditional ceramic substrate tape casting process to efficiently prepare the heat conduction substrate with high surface quality and uniform performance.
Compared with the traditional method for preparing the silicon rubber sheet by mould pressing, the equipment of the invention is simple, can carry out high-efficiency continuous production, has small defect and uniform performance of the prepared flexible silicon rubber substrate, can realize large-scale and industrialized production of the flexible silicon rubber substrate, and simultaneously, the casting equipment with adjustable parameters can flexibly prepare the flexible silicon rubber substrates with different thicknesses and different filler volume fractions.
Preferably, part or all of the spherical alumina dried in the step (1) is subjected to saturated hydroxyl activation treatment and silane coupling agent surface modification,
the saturated hydroxyl activation treatment is the activation treatment of spherical alumina by using 20mol/L NaOH or molten NaOH,
the silane coupling agent surface modification is to modify spherical alumina by a modifier, the weight ratio of the modifier to the spherical alumina is 1:1-3:1,
the modifier is one or more of 3- (methacryloyloxy) propyl trimethoxy silane, methyl triethoxy silane and vinyl triethoxy silane.
Preferably, the spherical alumina in the step (1) is dispersed by a dispersant before being added into the component A of the liquid silicone rubber;
the dispersant is one or more of methyl methacrylate, polyethylene glycol and polyacrylate.
Preferably, the thickener is gas phase SiO 2 One or more of polyvinyl alcohol and polymethyl methacrylate;
the viscosity of the casting slurry in the step (4) is 15000-650000 mPa.s, and the specific viscosity range ensures that the spherical alumina has the optimal suspension stability and dispersion condition in the liquid silicone rubber, thereby ensuring that the flexible silicone rubber substrate with uniform performance and high thermal conductivity can be continuously produced.
Preferably, the defoaming treatment in the step (5) is specifically operated to put the casting slurry into a vacuum defoaming machine for stirring and defoaming, the vacuum defoaming machine is set to have a vacuum degree of 0-0.095mPa, the stirring speed is 0-30 revolutions, the stirring time is 5-30min, and the stirring direction is switched once every 1-15 min.
More preferably, the stirring speed is 5-20 revolutions, the stirring time is 15min, and the stirring direction is switched every 5 min.
The casting machine in the step (6) is set to have the casting knife height of 100-3500 mu m, the casting speed of 0.01-1m/min, the crosslinking temperature of 30-100 ℃, the crosslinking time of 35-300min and the air draft speed of 0-300m 2 The percentage of tension of the base band is 20-80%.
More preferably, the casting machine in the step (6) is set as the height of the casting knife is 500- & lt 2000 & gt um, the casting speed is 0.01-0.6m/min, the crosslinking temperature is 70-100 ℃, the crosslinking time is 35-60min, and the air draft speed is 5-20m 2 The percentage of tension of the base band is 30-70%.
Drawings
FIG. 1 is a cross-sectional SEM photograph of a flexible silicone rubber substrate of example 9;
FIG. 2 is a cross-sectional SEM photograph of the flexible silicone rubber substrate of example 2;
FIG. 3 is a sectional SEM photograph of the flexible silicone rubber substrate of example 13;
FIG. 4 is an SEM photograph of spherical alumina;
FIG. 5 is a process flow diagram of the present invention.
FIG. 6 is a graph of the trend of thermal conductivity of a composite substrate as a function of filler loading
FIG. 7 is a graph showing the trend of thermal conductivity of a composite substrate as a function of filler particle size
Detailed Description
The technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the drawings in the embodiments of the present invention, and it is obvious that the described embodiments are only a part of the embodiments of the present invention, and not all of the embodiments. 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.
Example 1
A flexible silicon rubber substrate with high thermal conductivity only consists of addition type liquid silicon rubber with low viscosity and a thermal conductive filler, and is specifically prepared from the following raw materials in parts by weight:
the addition type liquid silicone rubber is composed of 100 parts of dimethyl siloxane and 10 parts of poly (dimethyl siloxane-co-methyl hydrogen siloxane) trimethyl silane.
The heat-conducting filler is 50 parts of spherical alumina particles with D50 particle size of 90 um.
The preparation method comprises the following steps:
(1) placing the spherical alumina in a drying oven at 100 ℃, and drying for 2h to obtain pretreated powder;
(2)100 parts of dimethyl siloxane is used as matrix slurry, and the viscosity is 4000mPa & s;
(3) dispersing 50 parts of spherical alumina treated in the step (1) uniformly by methyl methacrylate, and then adding the spherical alumina into the matrix slurry in the step (2) to mix uniformly;
(4) 10 parts of poly (dimethylsiloxane-co-methylhydrogensiloxane) trimethylsilane was added to the slurry prepared in step (3) to prepare a casting slurry having a viscosity of 4200 mPas.
(5) Placing the casting slurry prepared in the step (4) into a vacuum defoaming machine, stirring and defoaming, setting the vacuum degree of the vacuum defoaming machine to be 0.090mPa, stirring at the rotating speed of 5 revolutions, stirring for 15min, and switching the stirring direction once every 5 min;
(6) casting the casting slurry subjected to the defoaming treatment in the step (5) in a casting machine by using a casting knifeSetting the height to be 1500um, the casting speed to be 0.06m/min, heating and crosslinking the cast by a drying tunnel of the casting machine, wherein the crosslinking temperature is 100 ℃, the crosslinking time is 45min, and the air draft speed is 2m 2 And h, the tension percentage of the base band is 50%, and the base band is wound after being cured to obtain the flexible silicon rubber substrate with high thermal conductivity.
(7) And (4) cutting the coiled material obtained in the step (6) to obtain a finished product, wherein the thickness of the finished product is 735 um.
Example 2
A flexible silicon rubber substrate with high thermal conductivity only consists of addition type liquid silicon rubber with low viscosity and a thermal conductive filler, and is specifically prepared from the following raw materials in parts by weight:
the addition type liquid silicone rubber is composed of 100 parts of dimethyl siloxane and 10 parts of poly (dimethyl siloxane-co-methyl hydrogen siloxane) trimethyl silane.
The heat-conducting filler is 100 parts of spherical alumina particles with D50 particle size of 90 um.
The preparation method comprises the following steps:
(1) placing the spherical alumina in a drying oven at 100 ℃, and drying for 2h to obtain pretreated powder;
(2)100 parts of dimethyl silane is used as matrix slurry, and the viscosity is 4000mPa & s;
(3) dispersing 100 parts of the spherical alumina treated in the step (1) by using polyethylene glycol uniformly, and then adding the dispersed spherical alumina into the matrix slurry in the step (2) to mix uniformly;
(4) 10 parts of poly (dimethylsiloxane-co-methylhydrogensiloxane) trimethylsilane was added to the slurry prepared in step (3) to prepare a casting slurry having a viscosity of 8600 mPas.
(5) Placing the casting slurry prepared in the step (4) into a vacuum defoaming machine, stirring and defoaming, setting the vacuum degree of the vacuum defoaming machine to be 0.090mPa, stirring at the rotating speed of 5 revolutions, stirring for 15min, and switching the stirring direction once every 5 min;
(6) casting the casting slurry after the defoaming treatment in the step (5) in a casting machine, setting the height of a casting knife to be 1500 mu m, setting the casting speed to be 0.06m/min, heating and crosslinking the casting slurry by a drying tunnel of the casting machine, wherein the crosslinking temperature is 100 ℃, the crosslinking time is 45min,the air draft speed is 2m 2 And h, the tension percentage of the base band is 50%, and the base band is wound after being cured to obtain the flexible silicon rubber substrate with high thermal conductivity.
(7) And (4) cutting the coiled material obtained in the step (6) to obtain a finished product, wherein the thickness of the finished product is 850 mu m.
Example 3
A flexible silicon rubber substrate with high thermal conductivity only consists of addition type liquid silicon rubber with low viscosity and a thermal conductive filler, and is specifically prepared from the following raw materials in parts by weight:
the addition type liquid silicone rubber is composed of 100 parts of dimethyl siloxane and 10 parts of poly (dimethyl siloxane-co-methyl hydrogen siloxane) trimethyl silane.
The heat-conducting filler is 180 parts of spherical alumina particles with D50 particle size of 90 um.
The preparation method comprises the following steps:
(1) placing the spherical alumina in a drying oven at 100 ℃, and drying for 2h to obtain pretreated powder;
(2)100 parts of dimethyl siloxane is used as matrix slurry, and the viscosity is 4000mPa & s;
(3) dispersing 180 parts of spherical alumina treated in the step (1) with polyacrylate uniformly, and adding the dispersed spherical alumina into the base slurry in the step (2) to mix uniformly;
(4) 10 parts of poly (dimethylsiloxane-co-methylhydrogensiloxane) trimethylsilane was added to the slurry prepared in step (3) to prepare a casting slurry having a viscosity of 23500 mPas.
(5) Placing the casting slurry prepared in the step (4) into a vacuum defoaming machine, stirring and defoaming, setting the vacuum degree of the vacuum defoaming machine to be 0.090mPa, stirring at the rotating speed of 5 revolutions, stirring for 15min, and switching the stirring direction once every 5 min;
(6) casting the casting slurry subjected to the defoaming treatment in the step (5) in a casting machine, wherein the height of a casting knife is set to be 1500 mu m, the casting speed is 0.06m/min, a drying tunnel of the casting machine is used for heating and crosslinking the casting slurry, the crosslinking temperature is 100 ℃, the crosslinking time is 45min, and the air draft speed is 2m 2 The tension percentage of the base band is 50 percent, and the flexible silicon rubber base with high thermal conductivity is prepared by coiling after curingAnd (3) slicing.
(7) And (4) cutting the coiled material obtained in the step (6) to obtain a finished product, wherein the thickness of the finished product is 960 um.
Example 4
A flexible silicon rubber substrate with high thermal conductivity only consists of addition type liquid silicon rubber with low viscosity and a thermal conductive filler, and is specifically prepared from the following raw materials in parts by weight:
the addition type liquid silicone rubber is composed of 100 parts of dimethyl siloxane and 10 parts of poly (dimethyl siloxane-co-methyl hydrogen siloxane) trimethyl silane.
The heat-conducting filler is 280 parts of spherical alumina particles with D50 particle size of 90 um.
The preparation method comprises the following steps:
(1) placing the spherical alumina in a drying oven at 100 ℃, and drying for 2h to obtain pretreated powder;
(2)100 parts of dimethyl siloxane is used as matrix slurry, and the viscosity is 4000mPa & s;
(3) uniformly dispersing 280 parts of spherical alumina treated in the step (1) by using methyl methacrylate, and then adding the mixture into the matrix slurry in the step (2) to uniformly mix;
(4) 10 parts of poly (dimethylsiloxane-co-methylhydrogensiloxane) trimethylsilane was added to the slurry prepared in step (3) to prepare a casting slurry having a viscosity of 75800 mPas.
(5) Placing the casting slurry prepared in the step (4) into a vacuum defoaming machine, stirring and defoaming, setting the vacuum degree of the vacuum defoaming machine to be 0.090mPa, stirring at the rotating speed of 5 revolutions, stirring for 15min, and switching the stirring direction once every 5 min;
(6) casting the casting slurry subjected to the defoaming treatment in the step (5) in a casting machine, wherein the height of a casting knife is set to be 1500 mu m, the casting speed is 0.06m/min, a drying tunnel of the casting machine is used for heating and crosslinking the casting slurry, the crosslinking temperature is 100 ℃, the crosslinking time is 45min, and the air draft speed is 2m 2 And h, the tension percentage of the base band is 50%, and the base band is wound after being cured to obtain the flexible silicon rubber substrate with high thermal conductivity.
(7) And (4) cutting the coiled material obtained in the step (6) to obtain a finished product, wherein the thickness of the finished product is 1050 um.
Example 5
A flexible silicon rubber substrate with high thermal conductivity only consists of addition type liquid silicon rubber with low viscosity and a thermal conductive filler, and is specifically prepared from the following raw materials in parts by weight:
the addition type liquid silicone rubber is composed of 100 parts of dimethyl siloxane and 10 parts of poly (dimethyl siloxane-co-methyl hydrogen siloxane) trimethyl silane.
The heat conducting filler is 400 parts of spherical alumina particles with the D50 particle size of 5 um.
The preparation method comprises the following steps:
(1) placing the spherical alumina in a drying oven at 100 ℃, and drying for 2h to obtain pretreated powder;
(2)100 parts of dimethyl siloxane is used as matrix slurry, and the viscosity is 4000mPa & s;
(3) dispersing 400 parts of the spherical alumina treated in the step (1) uniformly by using polyacrylate, and then adding the mixture into the matrix slurry in the step (2) to mix uniformly;
(4) 10 parts of poly (dimethylsiloxane-co-methylhydrogensiloxane) trisilane was added to the slurry prepared in step (3) to prepare a casting slurry having a viscosity of 213000 mPas.
(5) Placing the casting slurry prepared in the step (4) into a vacuum defoaming machine, stirring and defoaming, setting the vacuum degree of the vacuum defoaming machine to be 0.090mPa, stirring at the rotating speed of 5 revolutions, stirring for 15min, and switching the stirring direction once every 5 min;
(6) casting the casting slurry subjected to the defoaming treatment in the step (5) in a casting machine, wherein the height of a casting knife is set to be 1500 mu m, the casting speed is 0.06m/min, a drying tunnel of the casting machine is used for heating and crosslinking the casting slurry, the crosslinking temperature is 100 ℃, the crosslinking time is 45min, and the air draft speed is 2m 2 And h, the tension percentage of the base band is 50%, and the base band is wound after being cured to obtain the flexible silicon rubber substrate with high thermal conductivity.
(7) And (4) cutting the coiled material obtained in the step (6) to obtain a finished product, wherein the thickness of the finished product is 1125 um.
Example 6
A flexible silicon rubber substrate with high thermal conductivity only consists of addition type liquid silicon rubber with low viscosity and a thermal conductive filler, and is specifically prepared from the following raw materials in parts by weight:
the addition type liquid silicone rubber is composed of 100 parts of dimethyl siloxane and 10 parts of poly (dimethyl siloxane-co-methyl hydrogen siloxane) trimethyl silane.
The heat conducting filler is 400 parts of spherical alumina particles with the D50 particle size of 20 um.
The preparation method comprises the following steps:
(1) placing the spherical alumina in a drying oven at 100 ℃, and drying for 2h to obtain pretreated powder;
(2)100 parts of dimethyl siloxane is used as matrix slurry, and the viscosity is 4000mPa & s;
(3) dispersing 400 parts of spherical alumina treated in the step (1) uniformly by methyl methacrylate, and adding the spherical alumina into the matrix slurry in the step (2) to mix uniformly;
(4) 10 parts of poly (dimethylsiloxane-co-methylhydrogensiloxane) trimethylsilane was added to the slurry prepared in step (3) to prepare a casting slurry having a viscosity of 213800 mPas.
(5) Placing the casting slurry prepared in the step (4) into a vacuum defoaming machine, stirring and defoaming, setting the vacuum degree of the vacuum defoaming machine to be 0.090mPa, stirring at the rotating speed of 5 revolutions, stirring for 15min, and switching the stirring direction once every 5 min;
(6) casting the casting slurry subjected to the defoaming treatment in the step (5) in a casting machine, wherein the height of a casting knife is set to be 1500 mu m, the casting speed is 0.06m/min, a drying tunnel of the casting machine is used for heating and crosslinking the casting slurry, the crosslinking temperature is 100 ℃, the crosslinking time is 45min, and the air draft speed is 2m 2 And h, the tension percentage of the base band is 50%, and the base band is wound after being cured to obtain the flexible silicon rubber substrate with high thermal conductivity.
(7) And (4) cutting the coiled material obtained in the step (6) to obtain a finished product, wherein the thickness of the finished product is 1150 um.
Example 7
A flexible silicon rubber substrate with high thermal conductivity only consists of addition type liquid silicon rubber with low viscosity and a thermal conductive filler, and is specifically prepared from the following raw materials in parts by weight:
the addition type liquid silicone rubber is composed of 100 parts of dimethyl siloxane and 10 parts of poly (dimethyl siloxane-co-methyl hydrogen siloxane) trimethyl silane.
The heat conducting filler is 400 parts of spherical alumina particles with D50 particle size of 40 um.
The preparation method comprises the following steps:
(1) placing the spherical alumina in a drying oven at 100 ℃, and drying for 2h to obtain pretreated powder;
(2)100 parts of dimethyl siloxane is used as matrix slurry, and the viscosity is 4000mPa & s;
(3) dispersing 400 parts of spherical alumina treated in the step (1) uniformly by methyl methacrylate, and adding the spherical alumina into the matrix slurry in the step (2) to mix uniformly;
(4) 10 parts of poly (dimethylsiloxane-co-methylhydrogensiloxane) trimethylsilane was added to the slurry prepared in step (3) to prepare a casting slurry having a viscosity of 213500 mPas.
(5) Placing the casting slurry prepared in the step (4) into a vacuum defoaming machine, stirring and defoaming, setting the vacuum degree of the vacuum defoaming machine to be 0.090mPa, stirring at the rotating speed of 5 revolutions, stirring for 15min, and switching the stirring direction once every 5 min;
(6) casting the casting slurry subjected to the defoaming treatment in the step (5) in a casting machine, setting the height of a casting knife to be 1500 mu m, setting the casting speed to be 0.06m/min, heating and crosslinking the casting slurry by a drying tunnel of the casting machine, wherein the crosslinking temperature is 100 ℃, the crosslinking time is 45min, and the air draft speed is 2m 2 And h, the tension percentage of the base band is 50%, and the base band is wound after being cured to obtain the flexible silicon rubber substrate with high thermal conductivity.
(7) And (4) cutting the coiled material obtained in the step (6) to obtain a finished product, wherein the thickness of the finished product is 1170 um.
Example 8
A flexible silicon rubber substrate with high thermal conductivity only consists of addition type liquid silicon rubber with low viscosity and a thermal conductive filler, and is specifically prepared from the following raw materials in parts by weight:
the addition type liquid silicone rubber is composed of 100 parts of dimethyl siloxane and 10 parts of poly (dimethyl siloxane-co-methyl hydrogen siloxane) trimethyl silane.
The heat conducting filler is 400 parts of spherical alumina particles with D50 particle size of 70 um.
The preparation method comprises the following steps:
(1) placing the spherical alumina in a drying oven at 100 ℃, and drying for 2h to obtain pretreated powder;
(2)100 parts of dimethyl siloxane is used as matrix slurry, and the viscosity is 4000mPa & s;
(3) dispersing 400 parts of spherical alumina treated in the step (1) uniformly by methyl methacrylate, and adding the spherical alumina into the matrix slurry in the step (2) to mix uniformly;
(4) 10 parts of poly (dimethylsiloxane-co-methylhydrogensiloxane) trimethylsilane was added to the slurry prepared in step (3) to prepare a casting slurry having a viscosity of 213800 mPas.
(5) Placing the casting slurry prepared in the step (4) into a vacuum defoaming machine, stirring and defoaming, setting the vacuum degree of the vacuum defoaming machine to be 0.090mPa, stirring at the rotating speed of 5 revolutions, stirring for 15min, and switching the stirring direction once every 5 min;
(6) casting the casting slurry subjected to the defoaming treatment in the step (5) in a casting machine, wherein the height of a casting knife is set to be 1500 mu m, the casting speed is 0.06m/min, a drying tunnel of the casting machine is used for heating and crosslinking the casting slurry, the crosslinking temperature is 100 ℃, the crosslinking time is 45min, and the air draft speed is 2m 2 And h, the tension percentage of the base band is 50%, and the base band is wound after being cured to obtain the flexible silicon rubber substrate with high thermal conductivity.
(7) And (4) cutting the coiled material obtained in the step (6) to obtain a finished product, wherein the thickness of the finished product is 1145 um.
Example 9
A flexible silicon rubber substrate with high thermal conductivity only consists of addition type liquid silicon rubber with low viscosity and a thermal conductive filler, and is specifically prepared from the following raw materials in parts by weight:
the addition type liquid silicone rubber is composed of 100 parts of dimethyl siloxane and 10 parts of poly (dimethyl siloxane-co-methyl hydrogen siloxane) trimethyl silane.
The heat conducting filler is 400 parts of spherical alumina particles with D50 particle size of 90 um.
The preparation method comprises the following steps:
(1) placing the spherical alumina in a drying oven at 100 ℃, and drying for 2h to obtain pretreated powder;
(2)100 parts of dimethyl siloxane is used as matrix slurry, and the viscosity is 4000mPa & s;
(3) dispersing 400 parts of spherical alumina treated in the step (1) uniformly by methyl methacrylate, and adding the spherical alumina into the matrix slurry in the step (2) to mix uniformly;
(4) 10 parts of poly (dimethylsiloxane-co-methylhydrogensiloxane) trimethylsilane was added to the slurry prepared in step (3) to prepare a casting slurry having a viscosity of 214500 mPas.
(5) Placing the casting slurry prepared in the step (4) into a vacuum defoaming machine, stirring and defoaming, setting the vacuum degree of the vacuum defoaming machine to be 0.090mPa, stirring at the rotating speed of 5 revolutions, stirring for 15min, and switching the stirring direction once every 5 min;
(6) casting the casting slurry subjected to the defoaming treatment in the step (5) in a casting machine, wherein the height of a casting knife is set to be 1500 mu m, the casting speed is 0.06m/min, a drying tunnel of the casting machine is used for heating and crosslinking the casting slurry, the crosslinking temperature is 100 ℃, the crosslinking time is 45min, and the air draft speed is 2m 2 And h, the tension percentage of the base band is 50%, and the base band is wound after being cured to obtain the flexible silicon rubber substrate with high thermal conductivity.
(7) And (4) cutting the coiled material obtained in the step (6) to obtain a finished product, wherein the thickness of the finished product is 1150 um.
Example 10
A flexible silicon rubber substrate with high thermal conductivity only consists of addition type liquid silicon rubber with low viscosity and a thermal conductive filler, and is specifically prepared from the following raw materials in parts by weight:
the addition type liquid silicone rubber is composed of 100 parts of dimethyl siloxane and 10 parts of poly (dimethyl siloxane-co-methyl hydrogen siloxane) trimethyl silane.
The heat conducting filler is 400 parts of spherical alumina particles with D50 particle size of 120 um.
The preparation method comprises the following steps:
(1) placing the spherical alumina in a drying oven at 100 ℃, and drying for 2h to obtain pretreated powder;
(2)100 parts of dimethyl siloxane is used as matrix slurry, and the viscosity is 4000mPa & s;
(3) dispersing 400 parts of spherical alumina treated in the step (1) uniformly by methyl methacrylate, and adding the spherical alumina into the matrix slurry in the step (2) to mix uniformly;
(4) 10 parts of poly (dimethylsiloxane-co-methylhydrogensiloxane) trimethylsilane was added to the slurry prepared in step (3) to prepare a casting slurry having a viscosity of 214000 mPas.
(5) Placing the casting slurry prepared in the step (4) into a vacuum defoaming machine, stirring and defoaming, setting the vacuum degree of the vacuum defoaming machine to be 0.090mPa, stirring at the rotating speed of 5 revolutions, stirring for 15min, and switching the stirring direction once every 5 min;
(6) casting the casting slurry subjected to the defoaming treatment in the step (5) in a casting machine, wherein the height of a casting knife is set to be 1500 mu m, the casting speed is 0.06m/min, a drying tunnel of the casting machine is used for heating and crosslinking the casting slurry, the crosslinking temperature is 100 ℃, the crosslinking time is 45min, and the air draft speed is 2m 2 And h, the tension percentage of the base band is 50%, and the base band is wound after being cured to obtain the flexible silicon rubber substrate with high thermal conductivity.
(7) And (4) cutting the coiled material obtained in the step (6) to obtain a finished product, wherein the thickness of the finished product is 1135 um.
Example 11
A flexible silicon rubber substrate with high thermal conductivity only consists of addition type liquid silicon rubber with low viscosity and a thermal conductive filler, and is specifically prepared from the following raw materials in parts by weight:
the addition type liquid silicone rubber consists of 100 parts of a component A and 10 parts of a component B;
the addition type liquid silicone rubber is composed of 100 parts of dimethyl siloxane and 10 parts of poly (dimethyl siloxane-co-methyl hydrogen siloxane) trimethyl silane.
The heat-conducting filler is 400 parts and is formed by mixing spherical alumina particles with D50 particle sizes of 5, 20 and 120um according to the weight ratio of 2:1: 7.
The preparation method comprises the following steps:
(1) placing the spherical alumina in a drying oven at 100 ℃, drying for 2h for later use, and obtaining pretreated powder;
(2)100 parts of dimethyl siloxane is used as matrix slurry, and the viscosity is 4000mPa & s;
(3) adding 400 parts of spherical alumina treated in the step (1) into methyl methacrylate for dispersion, adding the mixture into the matrix slurry in the step (2), and uniformly mixing;
(4) 10 parts of poly (dimethylsiloxane-co-methylhydrogensiloxane) trimethylsilane was added to the slurry prepared in step (3) to prepare a casting slurry having a viscosity of 216500 mPas.
(5) Placing the casting slurry prepared in the step (4) into a vacuum defoaming machine, stirring and defoaming, setting the vacuum degree of the vacuum defoaming machine to be 0.090mPa, stirring at the rotating speed of 5 revolutions, stirring for 15min, and switching the stirring direction once every 5 min;
(6) casting the casting slurry subjected to the defoaming treatment in the step (5) in a casting machine, wherein the height of a casting knife is set to be 1500 mu m, the casting speed is 0.06m/min, a drying tunnel of the casting machine is used for heating and crosslinking the casting slurry, the crosslinking temperature is 100 ℃, the crosslinking time is 45min, and the air draft speed is 2m 2 And h, the tension percentage of the base band is 50%, and the base band is wound after being cured to obtain the flexible silicon rubber substrate with high thermal conductivity.
(7) And (4) cutting the coiled material obtained in the step (6) to obtain a finished product, wherein the thickness of the finished product is 1150 um.
Example 12
A flexible silicon rubber substrate with high thermal conductivity only consists of addition type liquid silicon rubber with low viscosity and a thermal conductive filler, and is specifically prepared from the following raw materials in parts by weight:
the addition type liquid silicone rubber consists of 100 parts of dimethyl siloxane, 10 parts of poly (dimethyl siloxane-co-methyl hydrogen siloxane) trisilane and 10 parts of gas-phase SiO 2 And (4) forming.
The heat-conducting filler is 50 parts of spherical alumina particles with D50 particle size of 90 um.
The preparation method comprises the following steps:
(1) placing the spherical alumina in a drying oven at 100 ℃, and drying for 2h to obtain pretreated powder;
(2)100 parts of dimethyl siloxane is used as matrix slurry, and the viscosity is 4000mPa & s;
(3) dispersing 50 parts of spherical alumina treated in the step (1) uniformly by methyl methacrylate, and then adding the spherical alumina into the matrix slurry in the step (2) to mix uniformly;
(4) 10 parts of poly (dimethylsiloxane-co-methylhydrogensiloxane) trimethylsilane was added to the slurry prepared in step (3) to prepare a casting slurry having a viscosity of 552000 mPas.
(5) Placing the casting slurry prepared in the step (4) into a vacuum defoaming machine, stirring and defoaming, setting the vacuum degree of the vacuum defoaming machine to be 0.090mPa, stirring at the rotating speed of 5 revolutions, stirring for 15min, and switching the stirring direction once every 5 min;
(6) casting the casting slurry subjected to the defoaming treatment in the step (5) in a casting machine, wherein the height of a casting knife is set to be 1500 mu m, the casting speed is 0.06m/min, a drying tunnel of the casting machine is used for heating and crosslinking the casting slurry, the crosslinking temperature is 100 ℃, the crosslinking time is 45min, and the air draft speed is 2m 2 And h, the tension percentage of the base band is 50%, and the base band is wound after being cured to obtain the flexible silicon rubber substrate with high thermal conductivity.
(7) And (4) cutting the coiled material obtained in the step (6) to obtain a finished product, wherein the thickness of the finished product is 1160 um.
Example 13
A flexible silicon rubber substrate with high thermal conductivity only consists of addition type liquid silicon rubber with low viscosity and a heat-conducting filler, and is specifically prepared from the following raw materials in parts by weight:
the addition type liquid silicone rubber is prepared from 100 parts of dimethyl siloxane, 10 parts of poly (dimethyl siloxane-co-methyl hydrogen siloxane) trimethyl silane and 5 parts of gas-phase SiO 2 And (4) forming.
The heat-conducting filler is 100 parts of spherical alumina particles with D50 particle size of 90 um.
The preparation method comprises the following steps:
(1) placing the spherical alumina in a drying oven at 100 ℃, and drying for 2h to obtain pretreated powder;
(2)100 parts of dimethyl silane is used as matrix slurry, and the viscosity is 4000mPa & s;
(3) dispersing 100 parts of the spherical alumina treated in the step (1) by using polyethylene glycol uniformly, and then adding the dispersed spherical alumina into the matrix slurry in the step (2) to mix uniformly;
(4) 10 parts of poly (dimethylsiloxane-co-methylhydrogensiloxane) trimethylsilane was added to the slurry prepared in step (3) to prepare a casting slurry having a viscosity of 59100 mPas.
(5) Placing the casting slurry prepared in the step (4) into a vacuum defoaming machine, stirring and defoaming, setting the vacuum degree of the vacuum defoaming machine to be 0.090mPa, stirring at the rotating speed of 5 revolutions, stirring for 15min, and switching the stirring direction once every 5 min;
(6) casting the casting slurry subjected to the defoaming treatment in the step (5) in a casting machine, wherein the height of a casting knife is set to be 1500 mu m, the casting speed is 0.06m/min, a drying tunnel of the casting machine is used for heating and crosslinking the casting slurry, the crosslinking temperature is 100 ℃, the crosslinking time is 45min, and the air draft speed is 2m 2 And h, the tension percentage of the base band is 50%, and the base band is wound after being cured to obtain the flexible silicon rubber substrate with high thermal conductivity.
(7) And (4) cutting the coiled material obtained in the step (6) to obtain a finished product, wherein the thickness of the finished product is 1050 um.
Example 14
A flexible silicon rubber substrate with high thermal conductivity only consists of addition type liquid silicon rubber with low viscosity and a thermal conductive filler, and is specifically prepared from the following raw materials in parts by weight:
the addition type liquid silicone rubber is composed of 100 parts of dimethyl siloxane and 10 parts of poly (dimethyl siloxane-co-methyl hydrogen siloxane) trimethyl silane.
The heat-conducting filler is 400 parts and is formed by mixing spherical alumina particles with D50 particle sizes of 5, 20 and 120um according to the weight ratio of 2:1: 7.
The preparation method comprises the following steps:
(1) placing spherical alumina in a drying oven at 100 ℃, drying for 2h, then stirring and mixing with 20mol/L NaOH, filtering, and repeatedly washing with deionized water for three times to obtain pretreated powder;
adding the pretreated powder and 3- (methacryloyloxy) propyl trimethoxy silane into 160ml of deionized water according to a ratio of 3:5, then adding a proper amount of NaOH and absolute alcohol, mixing and ultrasonically treating for 1h, performing ball milling dispersion for 8h, washing the heat-conducting filler subjected to ball milling for 3 times by using absolute ethyl alcohol, and airing at room temperature for later use;
(2)100 parts of dimethyl siloxane is used as matrix slurry, and the viscosity is 4000mPa & s;
(3) adding 400 parts of spherical alumina treated in the step (1) into methyl methacrylate for dispersion, adding the mixture into the matrix slurry in the step (2), and uniformly mixing;
(4) 10 parts of poly (dimethylsiloxane-co-methylhydrogensiloxane) trimethylsilane was added to the slurry prepared in step (3) to prepare a casting slurry having a viscosity of 218000 mPas.
(5) Placing the casting slurry prepared in the step (4) into a vacuum defoaming machine, stirring and defoaming, setting the vacuum degree of the vacuum defoaming machine to be 0.090mPa, stirring at the rotating speed of 5 revolutions, stirring for 15min, and switching the stirring direction once every 5 min;
(6) casting the casting slurry subjected to the defoaming treatment in the step (5) in a casting machine, wherein the height of a casting knife is set to be 1500 mu m, the casting speed is 0.06m/min, a drying tunnel of the casting machine is used for heating and crosslinking the casting slurry, the crosslinking temperature is 100 ℃, the crosslinking time is 45min, and the air draft speed is 2m 2 And h, the tension percentage of the base band is 50%, and the base band is wound after being cured to obtain the flexible silicon rubber substrate with high thermal conductivity.
(7) And (4) cutting the coiled material obtained in the step (6) to obtain a finished product, wherein the thickness of the finished product is 1175 um.
Example 15
A flexible silicon rubber substrate with high thermal conductivity only consists of addition type liquid silicon rubber with low viscosity and a thermal conductive filler, and is specifically prepared from the following raw materials in parts by weight:
the addition type liquid silicone rubber is prepared from 100 parts of dimethyl siloxane, 10 parts of poly (dimethyl siloxane-co-methyl hydrogen siloxane) trimethyl silane and 5 parts of gas-phase SiO 2 And (4) forming.
The heat-conducting filler is 100 parts of spherical alumina particles with D50 particle size of 90 um.
The preparation method comprises the following steps:
(1) placing spherical alumina in a drying oven at 100 ℃, drying for 2h, then stirring and mixing with 20mol/L NaOH, filtering, and repeatedly washing with deionized water for three times to obtain pretreated powder;
adding the pretreated powder and 3- (methacryloyloxy) propyl trimethoxy silane into 160ml of deionized water according to a ratio of 3:5, then adding a proper amount of NaOH and absolute alcohol, mixing and ultrasonically treating for 1h, performing ball milling dispersion for 8h, washing the heat-conducting filler subjected to ball milling for 3 times by using absolute ethyl alcohol, and airing at room temperature for later use;
(2)100 parts of dimethyl silane is used as matrix slurry, and the viscosity is 4000mPa & s;
(3) dispersing 100 parts of the spherical alumina treated in the step (1) by using polyethylene glycol uniformly, and then adding the dispersed spherical alumina into the matrix slurry in the step (2) to mix uniformly;
(4) 10 parts of poly (dimethylsiloxane-co-methylhydrogensiloxane) trimethylsilane was added to the slurry prepared in step (3) to prepare a casting slurry having a viscosity of 621000 mPas.
(5) Placing the casting slurry prepared in the step (4) into a vacuum defoaming machine, stirring and defoaming, setting the vacuum degree of the vacuum defoaming machine to be 0.090mPa, stirring at the rotating speed of 5 revolutions, stirring for 15min, and switching the stirring direction once every 5 min;
(6) casting the casting slurry subjected to the defoaming treatment in the step (5) in a casting machine, wherein the height of a casting knife is set to be 1500 mu m, the casting speed is 0.06m/min, a drying tunnel of the casting machine is used for heating and crosslinking the casting slurry, the crosslinking temperature is 100 ℃, the crosslinking time is 45min, and the air draft speed is 2m 2 And h, the tension percentage of the base band is 50%, and the base band is wound after being cured to obtain the flexible silicon rubber substrate with high thermal conductivity.
(7) And (4) cutting the coiled material obtained in the step (6) to obtain a finished product, wherein the thickness of the finished product is 1075 um.
The thermal conductivity of the examples 1 to 15 is measured by a laser flash method (refer to the national standard GB/T22588-; the tensile strength of the silicone rubber substrate was determined in accordance with the national standard GB/T528-2009.
λ＝α×Cp×ρ (1)
In the formula: λ -thermal conductivity, in W/(m.K);
alpha-thermal diffusion coefficient in m 2 /s；
Cp-specific heat capacity, in J/(kg. K);
rho-density in kg/m 3 。
| Examples | Thermal conductivity W/(m. K) | |
| 1 | 0.131 | 1.34 |
| 2 | 0.210 | 1.82 |
| 3 | 0.568 | 2.45 |
| 4 | 0.986 | 2.32 |
| 5 | 0.778 | 5.59 |
| 6 | 0.907 | 3.45 |
| 7 | 0.945 | 2.34 |
| 8 | 0.958 | 2.86 |
| 9 | 1.025 | 2.17 |
| 10 | 1.163 | 2.02 |
| 11 | 1.213 | 1.95 |
| 12 | 0.158 | 3.35 |
| 13 | 0.242 | 2.51 |
| 14 | 1.375 | 4.02 |
| 15 | 0.385 | 3.49 |
From examples 1-10, the present invention combines low viscosity silicone rubber with spherical alumina by gel casting process to produce a thin, uniform performance, isotropic composite substrate with high thermal conductivity ranging from 0.311-1.163W/(m.K).
As can be seen from the comparison between examples 10 and 11, the flexible silicone rubber substrate to which alumina having a plurality of different particle sizes is mixed has a better thermal conductivity than the flexible silicone rubber substrate to which alumina having a single particle size is added.
The inventors found that examples 1 and 2, although also having good thermal conductivity and tensile strength, found that the low-loaded thermally conductive filler had a delamination phenomenon under an optical photograph of a cross section magnified 50 times, and thus, the inventors solved the problem by adding a thickener.
From the comparison between example 1 and example 12 and the comparison between example 2 and example 13, it can be seen that a proper amount of the thickener can improve the suspension stability and the dispersion uniformity of the spherical alumina in the liquid silicone rubber, thereby improving the heat conduction efficiency. (the problem of delamination of example 2 is shown in FIG. 2, and example 13 after addition of a thickener is shown in FIG. 3, showing only photographs of examples 2 and 13 as comparative examples).
The comparison between the example 10 and the example 14 and the comparison between the example 13 and the example 15 show that the activation modification of the spherical alumina can enable the spherical alumina and the liquid silicone rubber to have better interface bonding capability, and improve the heat conducting property and the tensile strength of the flexible silicone rubber substrate.
Variations and modifications to the above-described embodiments may occur to those skilled in the art, which fall within the scope and spirit of the above description. Therefore, the present invention is not limited to the specific embodiments disclosed and described above, and some modifications and variations of the present invention should fall within the scope of the claims of the present invention. Furthermore, although specific terms are employed herein, they are used in a generic and descriptive sense only and not for purposes of limitation.
Claims (10)
1. The flexible silicon rubber substrate with high thermal conductivity is characterized by only consisting of low-viscosity addition type liquid silicon rubber and heat-conducting filler, and is prepared from the following raw materials in parts by weight:
the addition type liquid silicone rubber consists of 100 parts of component A, 10 parts of component B and 0-10 parts of thickening agent;
the heat conducting filler is 50-400 parts and consists of spherical alumina with single grain size or more than one grain size.
2. The flexible silicone rubber substrate according to claim 1, wherein the a component is one or more of dimethicone, vinyl terminated dimethylpolysiloxane, vinyl MQ resin mixture, ethylbenzene;
the component B is one or more of poly (dimethyl siloxane-co-methyl hydrogen siloxane) trimethyl silane, monovinyl end-capped dimethyl (siloxane and polysiloxane) and a vinyl MQ resin mixture.
3. The flexible silicone rubber substrate according to claim 1, wherein the spherical alumina is unmodified spherical alumina, modified spherical alumina, or a mixture of both;
the modified spherical alumina is spherical alumina particles subjected to saturated hydroxyl activation treatment and silane coupling agent surface modification.
4. The flexible silicone rubber substrate according to claim 1 or 3, wherein the heat conductive filler is formed by mixing one or more spherical alumina particles having a D50 particle size of 5, 20, 40, 70, 90 and 120 um.
5. The flexible silicone rubber substrate according to claim 4, wherein the thickener is gas phase SiO 2 One or more of polyvinyl alcohol and polymethyl methacrylate.
6. The method for producing a flexible silicone rubber substrate according to any one of claims 1 to 5, characterized by comprising the steps of:
(1) drying the heat-conducting filler spherical alumina for later use;
(2) directly taking the component A of the liquid silicone rubber as matrix slurry, or adding a proper amount of thickening agent into the component A of the liquid silicone rubber and uniformly stirring to prepare matrix slurry;
(3) adding the heat-conducting filler treated in the step (1) into the matrix slurry in the step (2) according to a preset weight part, and uniformly mixing;
(4) adding a preset weight part of the component B of the liquid silicone rubber into the slurry prepared in the step (3) to prepare casting slurry;
(5) defoaming the casting slurry prepared in the step (4);
(6) and (5) casting the casting slurry subjected to defoaming treatment in the step (5) in a casting machine, heating and crosslinking the casting slurry in a drying tunnel of the casting machine, and coiling the casting slurry after curing to obtain the flexible silicon rubber substrate with high thermal conductivity.
7. The preparation method according to claim 6, wherein the spherical alumina dried in the step (1) is partially or completely subjected to saturated hydroxyl group activation treatment and silane coupling agent surface modification,
the saturated hydroxyl activation treatment is the activation treatment of spherical alumina by using 20mol/L NaOH or molten NaOH,
the silane coupling agent surface modification is to modify spherical alumina by a modifier, the weight ratio of the modifier to the spherical alumina is 1:1-3:1,
the modifier is one or more of 3- (methacryloyloxy) propyl trimethoxy silane, methyl triethoxy silane and vinyl triethoxy silane.
8. The production method according to claim 6 or 7, wherein the spherical alumina of step (1) is dispersed with a dispersant before being added to the A component of the liquid silicone rubber,
the dispersant is one or more of methyl methacrylate, polyethylene glycol and polyacrylate.
9. The method according to claim 6, wherein the thickener is gas phase SiO 2 One or more of polyvinyl alcohol and polymethyl methacrylate;
the viscosity of the casting slurry of the step (4) was 15000-650000 mPas.
10. The preparation method according to claim 6, characterized in that the defoaming treatment in the step (5) is specifically operated to put the casting slurry into a vacuum defoaming machine to be stirred and defoamed, the vacuum defoaming machine is set to have a vacuum degree of 0-0.095mPa, the stirring speed is 0-30 turns, the stirring time is 5-30min, and the stirring direction is switched once every 1-15 min;
the casting machine in the step (6) is set to have the casting knife height of 100-3500 mu m, the casting speed of 0.01-1m/min, the crosslinking temperature of 30-100 ℃, the crosslinking time of 35-300min and the air draft speed of 0-300m 2 The percentage of tension of the base band is 20-80%.
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Citations (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN103146198A (en) * | 2013-03-12 | 2013-06-12 | 深圳市博恩实业有限公司 | Heat conducting composite material and heat conducting composite sheet prepared by applying same |
| CN103436018A (en) * | 2013-08-23 | 2013-12-11 | 深圳市鸿富诚屏蔽材料有限公司 | High-toughness ultrathin heat-conducting silica gel gasket and preparation method thereof |
| CN103709757A (en) * | 2013-12-30 | 2014-04-09 | 无锡中石油润滑脂有限责任公司 | Insulating and heat-conducting silicone grease and preparation method thereof |
| CN113563721A (en) * | 2020-04-29 | 2021-10-29 | 杭州有容新材料有限公司 | High-tear-strength heat-conducting silica gel material and preparation method thereof |
-
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Patent Citations (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN103146198A (en) * | 2013-03-12 | 2013-06-12 | 深圳市博恩实业有限公司 | Heat conducting composite material and heat conducting composite sheet prepared by applying same |
| CN103436018A (en) * | 2013-08-23 | 2013-12-11 | 深圳市鸿富诚屏蔽材料有限公司 | High-toughness ultrathin heat-conducting silica gel gasket and preparation method thereof |
| CN103709757A (en) * | 2013-12-30 | 2014-04-09 | 无锡中石油润滑脂有限责任公司 | Insulating and heat-conducting silicone grease and preparation method thereof |
| CN113563721A (en) * | 2020-04-29 | 2021-10-29 | 杭州有容新材料有限公司 | High-tear-strength heat-conducting silica gel material and preparation method thereof |
Non-Patent Citations (1)
| Title |
|---|
| 吴中夏: ""导热硅橡胶制备及其热性能研究"" * |
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