CN115124843A - Electromagnetic shielding composite material with low reflection characteristic and preparation method thereof - Google Patents
Electromagnetic shielding composite material with low reflection characteristic and preparation method thereof Download PDFInfo
- Publication number
- CN115124843A CN115124843A CN202210577905.XA CN202210577905A CN115124843A CN 115124843 A CN115124843 A CN 115124843A CN 202210577905 A CN202210577905 A CN 202210577905A CN 115124843 A CN115124843 A CN 115124843A
- Authority
- CN
- China
- Prior art keywords
- silicone rubber
- graphene
- electromagnetic shielding
- fiber
- chopped carbon
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Pending
Links
- 239000002131 composite material Substances 0.000 title claims abstract description 80
- 238000002360 preparation method Methods 0.000 title claims abstract description 42
- OKTJSMMVPCPJKN-UHFFFAOYSA-N Carbon Chemical compound [C] OKTJSMMVPCPJKN-UHFFFAOYSA-N 0.000 claims abstract description 103
- 229910021389 graphene Inorganic materials 0.000 claims abstract description 101
- 239000000835 fiber Substances 0.000 claims abstract description 85
- 239000012528 membrane Substances 0.000 claims abstract description 59
- 229920000049 Carbon (fiber) Polymers 0.000 claims abstract description 56
- 239000004917 carbon fiber Substances 0.000 claims abstract description 56
- XEEYBQQBJWHFJM-UHFFFAOYSA-N Iron Chemical compound [Fe] XEEYBQQBJWHFJM-UHFFFAOYSA-N 0.000 claims abstract description 54
- 229920002379 silicone rubber Polymers 0.000 claims abstract description 54
- 239000004945 silicone rubber Substances 0.000 claims abstract description 50
- 239000007788 liquid Substances 0.000 claims abstract description 44
- VNWKTOKETHGBQD-UHFFFAOYSA-N methane Chemical compound C VNWKTOKETHGBQD-UHFFFAOYSA-N 0.000 claims abstract description 29
- 229910052742 iron Inorganic materials 0.000 claims abstract description 27
- 238000001291 vacuum drying Methods 0.000 claims abstract description 21
- 238000002156 mixing Methods 0.000 claims abstract description 19
- 238000006243 chemical reaction Methods 0.000 claims abstract description 13
- 239000000203 mixture Substances 0.000 claims abstract description 10
- 238000003756 stirring Methods 0.000 claims abstract description 9
- -1 methyl vinyl Chemical group 0.000 claims description 24
- BASFCYQUMIYNBI-UHFFFAOYSA-N platinum Chemical compound [Pt] BASFCYQUMIYNBI-UHFFFAOYSA-N 0.000 claims description 16
- 229920001296 polysiloxane Polymers 0.000 claims description 16
- 239000003112 inhibitor Substances 0.000 claims description 14
- 238000000034 method Methods 0.000 claims description 13
- UFHFLCQGNIYNRP-UHFFFAOYSA-N Hydrogen Chemical compound [H][H] UFHFLCQGNIYNRP-UHFFFAOYSA-N 0.000 claims description 8
- VYPSYNLAJGMNEJ-UHFFFAOYSA-N Silicium dioxide Chemical compound O=[Si]=O VYPSYNLAJGMNEJ-UHFFFAOYSA-N 0.000 claims description 8
- 239000006229 carbon black Substances 0.000 claims description 8
- 239000003054 catalyst Substances 0.000 claims description 8
- 229910052739 hydrogen Inorganic materials 0.000 claims description 8
- 239000001257 hydrogen Substances 0.000 claims description 8
- 229910052697 platinum Inorganic materials 0.000 claims description 8
- 230000035484 reaction time Effects 0.000 claims description 2
- 230000005670 electromagnetic radiation Effects 0.000 abstract description 17
- LFQSCWFLJHTTHZ-UHFFFAOYSA-N Ethanol Chemical compound CCO LFQSCWFLJHTTHZ-UHFFFAOYSA-N 0.000 description 36
- 239000011347 resin Substances 0.000 description 23
- 229920005989 resin Polymers 0.000 description 23
- 238000010521 absorption reaction Methods 0.000 description 15
- 239000007864 aqueous solution Substances 0.000 description 12
- XMBWDFGMSWQBCA-UHFFFAOYSA-N hydrogen iodide Chemical compound I XMBWDFGMSWQBCA-UHFFFAOYSA-N 0.000 description 12
- 230000000052 comparative effect Effects 0.000 description 11
- 230000008569 process Effects 0.000 description 9
- 239000000243 solution Substances 0.000 description 8
- QYLFHLNFIHBCPR-UHFFFAOYSA-N 1-ethynylcyclohexan-1-ol Chemical group C#CC1(O)CCCCC1 QYLFHLNFIHBCPR-UHFFFAOYSA-N 0.000 description 6
- ZCYVEMRRCGMTRW-UHFFFAOYSA-N 7553-56-2 Chemical compound [I] ZCYVEMRRCGMTRW-UHFFFAOYSA-N 0.000 description 6
- UXVMQQNJUSDDNG-UHFFFAOYSA-L Calcium chloride Chemical compound [Cl-].[Cl-].[Ca+2] UXVMQQNJUSDDNG-UHFFFAOYSA-L 0.000 description 6
- 229910001628 calcium chloride Inorganic materials 0.000 description 6
- 239000001110 calcium chloride Substances 0.000 description 6
- 238000004140 cleaning Methods 0.000 description 6
- 238000002347 injection Methods 0.000 description 6
- 239000007924 injection Substances 0.000 description 6
- 239000011630 iodine Substances 0.000 description 6
- 229910052740 iodine Inorganic materials 0.000 description 6
- 238000011056 performance test Methods 0.000 description 6
- 238000006722 reduction reaction Methods 0.000 description 6
- 238000002791 soaking Methods 0.000 description 6
- 238000009987 spinning Methods 0.000 description 6
- 238000005507 spraying Methods 0.000 description 6
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 description 6
- 238000002166 wet spinning Methods 0.000 description 6
- 239000000463 material Substances 0.000 description 5
- 238000012360 testing method Methods 0.000 description 5
- 239000011159 matrix material Substances 0.000 description 4
- 239000003575 carbonaceous material Substances 0.000 description 3
- 230000007246 mechanism Effects 0.000 description 3
- 239000002041 carbon nanotube Substances 0.000 description 2
- 229910021393 carbon nanotube Inorganic materials 0.000 description 2
- 238000005260 corrosion Methods 0.000 description 2
- 230000007797 corrosion Effects 0.000 description 2
- 238000011161 development Methods 0.000 description 2
- 230000018109 developmental process Effects 0.000 description 2
- 229910052751 metal Inorganic materials 0.000 description 2
- 239000002184 metal Substances 0.000 description 2
- 238000012545 processing Methods 0.000 description 2
- 238000005299 abrasion Methods 0.000 description 1
- 230000009286 beneficial effect Effects 0.000 description 1
- 230000005540 biological transmission Effects 0.000 description 1
- 238000004891 communication Methods 0.000 description 1
- 230000003247 decreasing effect Effects 0.000 description 1
- 230000007547 defect Effects 0.000 description 1
- 238000013461 design Methods 0.000 description 1
- 238000005516 engineering process Methods 0.000 description 1
- 230000036541 health Effects 0.000 description 1
- 238000009776 industrial production Methods 0.000 description 1
- 238000004519 manufacturing process Methods 0.000 description 1
- 239000007769 metal material Substances 0.000 description 1
- 150000002739 metals Chemical class 0.000 description 1
- 238000012986 modification Methods 0.000 description 1
- 230000004048 modification Effects 0.000 description 1
- 238000000465 moulding Methods 0.000 description 1
- 230000035515 penetration Effects 0.000 description 1
- 230000007903 penetration ability Effects 0.000 description 1
- 229920000642 polymer Polymers 0.000 description 1
Images
Classifications
-
- C—CHEMISTRY; METALLURGY
- C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
- C08J—WORKING-UP; GENERAL PROCESSES OF COMPOUNDING; AFTER-TREATMENT NOT COVERED BY SUBCLASSES C08B, C08C, C08F, C08G or C08H
- C08J5/00—Manufacture of articles or shaped materials containing macromolecular substances
- C08J5/18—Manufacture of films or sheets
-
- H—ELECTRICITY
- H05—ELECTRIC TECHNIQUES NOT OTHERWISE PROVIDED FOR
- H05K—PRINTED CIRCUITS; CASINGS OR CONSTRUCTIONAL DETAILS OF ELECTRIC APPARATUS; MANUFACTURE OF ASSEMBLAGES OF ELECTRICAL COMPONENTS
- H05K9/00—Screening of apparatus or components against electric or magnetic fields
- H05K9/0073—Shielding materials
- H05K9/0081—Electromagnetic shielding materials, e.g. EMI, RFI shielding
-
- C—CHEMISTRY; METALLURGY
- C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
- C08J—WORKING-UP; GENERAL PROCESSES OF COMPOUNDING; AFTER-TREATMENT NOT COVERED BY SUBCLASSES C08B, C08C, C08F, C08G or C08H
- C08J2383/00—Characterised by the use of macromolecular compounds obtained by reactions forming in the main chain of the macromolecule a linkage containing silicon with or without sulfur, nitrogen, oxygen, or carbon only; Derivatives of such polymers
- C08J2383/04—Polysiloxanes
- C08J2383/07—Polysiloxanes containing silicon bound to unsaturated aliphatic groups
-
- C—CHEMISTRY; METALLURGY
- C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
- C08J—WORKING-UP; GENERAL PROCESSES OF COMPOUNDING; AFTER-TREATMENT NOT COVERED BY SUBCLASSES C08B, C08C, C08F, C08G or C08H
- C08J2483/00—Characterised by the use of macromolecular compounds obtained by reactions forming in the main chain of the macromolecule a linkage containing silicon with or without sulfur, nitrogen, oxygen, or carbon only; Derivatives of such polymers
- C08J2483/04—Polysiloxanes
- C08J2483/05—Polysiloxanes containing silicon bound to hydrogen
-
- C—CHEMISTRY; METALLURGY
- C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
- C08K—Use of inorganic or non-macromolecular organic substances as compounding ingredients
- C08K2201/00—Specific properties of additives
- C08K2201/002—Physical properties
- C08K2201/003—Additives being defined by their diameter
-
- C—CHEMISTRY; METALLURGY
- C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
- C08K—Use of inorganic or non-macromolecular organic substances as compounding ingredients
- C08K2201/00—Specific properties of additives
- C08K2201/002—Physical properties
- C08K2201/004—Additives being defined by their length
-
- C—CHEMISTRY; METALLURGY
- C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
- C08K—Use of inorganic or non-macromolecular organic substances as compounding ingredients
- C08K2201/00—Specific properties of additives
- C08K2201/014—Additives containing two or more different additives of the same subgroup in C08K
-
- C—CHEMISTRY; METALLURGY
- C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
- C08K—Use of inorganic or non-macromolecular organic substances as compounding ingredients
- C08K7/00—Use of ingredients characterised by shape
- C08K7/02—Fibres or whiskers
- C08K7/04—Fibres or whiskers inorganic
- C08K7/06—Elements
Landscapes
- Chemical & Material Sciences (AREA)
- Engineering & Computer Science (AREA)
- Manufacturing & Machinery (AREA)
- Materials Engineering (AREA)
- Microelectronics & Electronic Packaging (AREA)
- Electromagnetism (AREA)
- Physics & Mathematics (AREA)
- Health & Medical Sciences (AREA)
- Chemical Kinetics & Catalysis (AREA)
- Medicinal Chemistry (AREA)
- Polymers & Plastics (AREA)
- Organic Chemistry (AREA)
- Shielding Devices Or Components To Electric Or Magnetic Fields (AREA)
- Compositions Of Macromolecular Compounds (AREA)
Abstract
The invention relates to an electromagnetic shielding composite material with low reflection characteristic and a preparation method thereof, wherein the preparation method comprises the following steps: firstly, flatly paving a graphene fiber film at the bottom of an iron mold; mixing and stirring uncured silicone rubber liquid and short carbon fibers at a high speed, and placing the mixture in a vacuum drying oven for defoaming after uniform mixing; pouring the defoamed short carbon fiber/silicone rubber premixed solution into an iron mold to be poured on the graphene fiber membrane; and step four, placing the iron mold in a flat vulcanizing machine, and carrying out curing reaction to obtain the chopped carbon fiber/graphene fiber/silicone rubber composite membrane. The chopped carbon fiber/graphene fiber/silicone rubber composite film is light and soft, has electromagnetic shielding performance with low reflection characteristic, and reduces secondary pollution of electromagnetic radiation while shielding the electromagnetic radiation.
Description
Technical Field
The invention belongs to the technical field of functional composite materials, and particularly relates to an electromagnetic shielding composite material with low reflection characteristic and a preparation method thereof.
Background
With the rapid development of internet communication technology and the wide application of highly integrated microcircuit electronic devices, electromagnetic radiation pollution is becoming more serious, and the electromagnetic radiation pollution becomes a social problem which cannot be ignored. Electromagnetic compatibility has received increasing attention to attenuate electromagnetic radiation to protect human health, the normal operation of electronic devices, and industrial production from electromagnetic radiation. Among them, electromagnetic shielding is an important and effective method in electromagnetic compatibility design.
At present, metals and their composite materials are widely used for manufacturing electromagnetic shielding materials. Although metal has excellent electromagnetic shielding performance, it has high density, poor abrasion resistance and poor corrosion resistance, often needs surface modification or is loaded with additional protection equipment, and cannot meet the development requirement of the current portable small electronic equipment. Compared with metal materials, the carbon material has the advantages of small density, good conductivity, high temperature resistance, corrosion resistance, convenient processing and the like, and has huge application potential in the field of electromagnetic shielding. Pure carbon materials are difficult to use alone as electromagnetic shielding materials due to size and structural limitations. Furthermore, all the characteristics of the electromagnetic shield cannot be solved by a single material in consideration. Therefore, it is considered that a proper amount of carbon material is compounded with the polymer through a certain processing process, and thus a high-performance electromagnetic shielding composite material with light weight, flexibility and high absorption is obtained.
Furthermore, the shielding mechanism of conventional electromagnetic shielding materials is dominated by reflection. The shielded electromagnetic radiation is mostly reflected into the surrounding environment again through the shielding layer, causing secondary pollution of the electromagnetic radiation.
Disclosure of Invention
Based on the above defects in the prior art, the invention provides an electromagnetic shielding composite material with low reflection characteristic and a preparation method thereof.
In order to achieve the purpose, the invention adopts the following technical scheme:
a preparation method of an electromagnetic shielding composite material with low reflection characteristic comprises the following steps:
firstly, flatly paving a graphene fiber film at the bottom of an iron mold;
mixing and stirring uncured silicone rubber liquid and short carbon fibers at a high speed, and placing the mixture in a vacuum drying oven for defoaming after uniform mixing;
pouring the defoamed short carbon fiber/silicone rubber premixed solution into an iron mold to be poured on the graphene fiber membrane;
and step four, placing the iron mold in a flat vulcanizing machine, and carrying out curing reaction to obtain the chopped carbon fiber/graphene fiber/silicone rubber composite membrane.
Preferably, the surface density of the graphene fiber membrane is 2.5-40 g/m 2 The diameter of each single graphene fiber is 30-50 mu m.
Preferably, the uncured silicone rubber liquid is prepared from the following components in parts by weight:
100 parts of methyl vinyl polysiloxane, 5-50 parts of white carbon black, 5-40 parts of hydrogen-containing polysiloxane, 0.05-0.5 part of platinum catalyst and 0.03-0.3 part of inhibitor.
Preferably, the uncured silicone rubber liquid and the chopped carbon fibers are blended according to the following parts by weight:
100 parts of uncured silicone rubber liquid and 0.001-0.1 part of chopped carbon fiber.
Preferably, the chopped carbon fibers have the length of 3-9 mm, the diameter of 5-15 mu m and the electric conductivity of 50000-100000S/m.
Preferably, the temperature of the curing reaction is 25-60 ℃, the curing reaction time is 2-6 h, and the applied pressure of the curing reaction is 0.001-1 MPa.
The invention also provides the electromagnetic shielding composite material prepared by the preparation method of any scheme, and the electromagnetic shielding composite material is a chopped carbon fiber/graphene fiber/silicone rubber composite film.
Preferably, the chopped carbon fiber content in the chopped carbon fiber/graphene fiber/silicone rubber composite membrane is 0.001-0.1 wt%.
As a preferable scheme, the content of graphene in the chopped carbon fiber/graphene fiber/silicone rubber composite membrane is 0.1-1 wt%.
Preferably, the thickness of the chopped carbon fiber/graphene fiber/silicone rubber composite film is 1-5 mm.
Compared with the prior art, the invention has the beneficial effects that:
the electromagnetic shielding composite material is light and flexible, has electromagnetic shielding performance with low reflection characteristic, can absorb most of electromagnetic radiation while shielding the electromagnetic radiation, and greatly reduces the secondary pollution of the electromagnetic radiation.
The preparation method of the electromagnetic shielding composite material uses addition type silicon rubber as a matrix, is environment-friendly, pollution-free and harmless to human bodies, has a simple composite molding process of the material, and is easy for batch preparation.
Drawings
Fig. 1 is a surface photomicrograph of a chopped carbon fiber/graphene fiber/silicone rubber composite film of example 1 of the present invention;
FIG. 2 is a test chart of electromagnetic shielding performance of the chopped carbon fiber/graphene fiber/silicone rubber composite membrane of example 1 in the X frequency band (8.2 GHz-12.4 GHz); wherein SE T Indicating the total shielding effectiveness, SE R Indicating reflection loss, SE A Represents the absorption loss, T represents the transmission coefficient, R represents the reflection coefficient, a represents the absorption coefficient;
fig. 3 is a test chart of electromagnetic shielding performance of the chopped carbon fiber/graphene fiber/silicone rubber composite film of embodiment 1 of the present invention in a P-band (12.4 GHz-18.0 GHz).
Detailed Description
The technical solution of the present invention will be further explained by the following specific examples.
Example 1:
the preparation method of the electromagnetic shielding composite material of the embodiment specifically comprises the following steps:
preparation of graphene fiber membrane
By adopting a wet spinning process, under the thrust of an injection pump, 5mL of 3 wt% graphene oxide spinning aqueous solution is passed through a needle with the diameter of 110 mu m and 5 wt% calcium chloride aqueous solution to prepare the graphene oxide fiber. And spraying ethanol and vacuum drying to obtain the graphene oxide fiber membrane. And then, preparing the graphene fiber membrane by a reduction reaction at the ambient temperature of 60 ℃ and under the soaking of a hydriodic acid solution. And (3) repeatedly cleaning the graphene fiber membrane by using ethanol to remove redundant hydriodic acid and elemental iodine. Finally, ethanol and water were removed by vacuum drying to obtain a dried graphene fiber membrane.
Secondly, preparation of resin prefabricated liquid
100g of methyl vinyl polysiloxane, 30g of white carbon black, 10g of hydrogen-containing polysiloxane, 0.15g of platinum catalyst and 0.1g of inhibitor are blended and stirred to prepare the uncured silicone rubber liquid. Wherein the inhibitor is 1-ethynylcyclohexanol.
Mixing and stirring uncured 20g of silicone rubber liquid and 0.001g of chopped carbon fibers with the length of 6mm at a high speed, placing the mixture in a vacuum drying oven for defoaming after uniformly mixing, and preparing the resin prefabricated liquid.
Preparation of electromagnetic shielding composite material
Flatly paving the graphene fiber membrane prepared in the first step at the bottom of the iron mold;
pouring the resin prefabricated liquid prepared in the step two into an iron mold to be poured on the graphene fiber membrane;
and then putting the iron mold into a flat vulcanizing machine, and carrying out curing reaction for 2 hours under the conditions of 1MPa pressure and 60 ℃ to obtain the chopped carbon fiber/graphene fiber/silicone rubber composite membrane.
Wherein the thickness of the composite film is 3mm, the content of the chopped carbon fibers is 0.005 wt%, and the content of the graphene is 0.5 wt%.
As shown in fig. 1, in a silicon rubber matrix, a graphene fiber film is located at the bottom of the silicon rubber matrix and serves as a shielding layer; the chopped carbon fibers are uniformly dispersed in the matrix as an absorption layer.
The electromagnetic shielding performance test chart of the electromagnetic shielding composite material prepared in the embodiment at the X frequency band (8.2-12.4 GHz) is shown in FIG. 2, and the total electromagnetic shielding effectiveness of the composite film at the 8.2-12.4 GHz frequency band is 21.9-22.2 dB; the reflection loss and the reflection coefficient both decrease rapidly with increasing frequency, and the absorption loss and the absorption coefficient both increase rapidly with increasing frequency, because as the frequency increases, the penetration of incident electromagnetic radiation increases, and more incident electromagnetic waves enter the composite film to be absorbed; the reflection loss is 0.7-4.5 dB, and the reflection coefficient is 0.15-0.65, which means that only 15% of electromagnetic radiation is reflected at the lowest; the absorption loss is 17.6-21.2 dB, and the absorption is 0.34-0.85, which means that up to 85% of incident electromagnetic radiation is absorbed.
The electromagnetic shielding performance test chart of the electromagnetic shielding composite material prepared in the embodiment at the P frequency band (12.4 to 18.0GHz) is shown in fig. 3, and the total electromagnetic shielding effectiveness of the composite film at the 12.4 to 18.0GHz frequency band is 19.4 to 21.0 dB; the reflection loss is 0.1-1.1 dB, the reflection coefficient is 0.02-0.22, and only 2% of electromagnetic radiation is reflected at the lowest; the absorption loss is 18.4-20.9 dB, and the absorption is 0.77-0.97, which means that the shielding mechanism of the composite film in the frequency band mainly takes the absorption loss, and the maximum 97% of electromagnetic waves are absorbed.
Example 2:
the preparation method of the electromagnetic shielding composite material of the embodiment specifically comprises the following steps:
preparation of graphene fiber membrane
By adopting a wet spinning process, under the thrust of an injection pump, 2.5mL of 3 wt% graphene oxide spinning aqueous solution passes through a needle with the diameter of 110 mu m and 5 wt% calcium chloride aqueous solution to prepare the graphene oxide fiber. And spraying ethanol and vacuum drying to obtain the graphene oxide fiber membrane. And then, preparing the graphene fiber membrane through a reduction reaction at the ambient temperature of 60 ℃ and under the soaking of a hydriodic acid solution. And (3) repeatedly cleaning the graphene fiber membrane by using ethanol to remove redundant hydriodic acid and elemental iodine. Finally, ethanol and water were removed by vacuum drying to obtain a dried graphene fiber membrane.
Secondly, preparation of resin prefabricated liquid
100g of methyl vinyl polysiloxane, 30g of white carbon black, 10g of hydrogen-containing polysiloxane, 0.15g of platinum catalyst and 0.1g of inhibitor are blended and stirred to prepare the uncured silicone rubber liquid. Wherein the inhibitor is 1-ethynyl cyclohexanol.
Mixing and stirring uncured 20g of silicone rubber liquid and 0.001g of chopped carbon fibers with the length of 6mm at a high speed, placing the mixture in a vacuum drying oven for defoaming after uniformly mixing, and preparing the resin prefabricated liquid.
Preparation of electromagnetic shielding composite material
Flatly paving the graphene fiber membrane prepared in the first step at the bottom of the iron mold;
pouring the resin prefabricated liquid prepared in the second step into an iron mold, and pouring the resin prefabricated liquid on the graphene fiber membrane;
and then putting the iron mould into a flat vulcanizing machine, and carrying out curing reaction for 2 hours under the conditions of 1MPa pressure and 60 ℃ to obtain the chopped carbon fiber/graphene fiber/silicone rubber composite membrane.
Wherein the thickness of the composite film is 3mm, the content of the chopped carbon fibers is 0.005 wt%, and the content of the graphene is 0.25 wt%.
Example 3:
the preparation method of the electromagnetic shielding composite material of the embodiment specifically comprises the following steps:
preparation of graphene fiber membrane
By adopting a wet spinning process, under the thrust of an injection pump, 10mL of 3 wt% graphene oxide spinning aqueous solution passes through a needle with the diameter of 110 mu m and 5 wt% calcium chloride aqueous solution to prepare the graphene oxide fiber. And spraying ethanol and vacuum drying to obtain the graphene oxide fiber membrane. And then, preparing the graphene fiber membrane by a reduction reaction at the ambient temperature of 60 ℃ and under the soaking of a hydriodic acid solution. And (3) repeatedly cleaning the graphene fiber membrane by using ethanol to remove redundant hydriodic acid and elemental iodine. Finally, ethanol and water were removed by vacuum drying to obtain a dried graphene fiber membrane.
Secondly, preparation of resin prefabricated liquid
100g of methyl vinyl polysiloxane, 30g of white carbon black, 10g of hydrogen-containing polysiloxane, 0.15g of platinum catalyst and 0.1g of inhibitor are blended and stirred to prepare the uncured silicone rubber liquid. Wherein the inhibitor is 1-ethynylcyclohexanol.
Mixing and stirring uncured 20g of silicone rubber liquid and 0.001g of chopped carbon fibers with the length of 6mm at a high speed, placing the mixture in a vacuum drying oven for defoaming after uniformly mixing, and preparing the resin prefabricated liquid.
Preparation of electromagnetic shielding composite material
Flatly paving the graphene fiber membrane prepared in the first step at the bottom of the iron mold;
pouring the resin prefabricated liquid prepared in the step two into an iron mold, and pouring the resin prefabricated liquid on the graphene fiber membrane;
and then putting the iron mould into a flat vulcanizing machine, and carrying out curing reaction for 2 hours under the conditions of 1MPa pressure and 60 ℃ to obtain the chopped carbon fiber/graphene fiber/silicone rubber composite membrane.
Wherein the thickness of the composite film is 3mm, the content of the chopped carbon fibers is 0.005 wt%, and the content of the graphene is 1 wt%.
Example 4:
the preparation method of the electromagnetic shielding composite material of the embodiment specifically comprises the following steps:
preparation of graphene fiber membrane
By adopting a wet spinning process, under the thrust of an injection pump, 5mL of 3 wt% graphene oxide spinning aqueous solution is passed through a needle with the diameter of 110 mu m and 5 wt% calcium chloride aqueous solution to prepare the graphene oxide fiber. And spraying ethanol and vacuum drying to obtain the graphene oxide fiber membrane. And then, preparing the graphene fiber membrane by a reduction reaction at the ambient temperature of 60 ℃ and under the soaking of a hydriodic acid solution. And (3) repeatedly cleaning the graphene fiber membrane by using ethanol to remove redundant hydriodic acid and elemental iodine. Finally, ethanol and water were removed by vacuum drying to obtain a dried graphene fiber membrane.
Secondly, preparation of resin prefabricated liquid
100g of methyl vinyl polysiloxane, 30g of white carbon black, 10g of hydrogen-containing polysiloxane, 0.15g of platinum catalyst and 0.1g of inhibitor are blended and stirred to prepare an uncured silicone rubber liquid. Wherein the inhibitor is 1-ethynylcyclohexanol.
Mixing and stirring uncured 20g of silicone rubber liquid and 0.0002g of chopped carbon fibers with the length of 6mm at a high speed, placing the mixture in a vacuum drying oven for defoaming after uniform mixing, and preparing the resin prefabricated liquid.
Preparation of electromagnetic shielding composite material
Flatly paving the graphene fiber membrane prepared in the first step at the bottom of the iron mold;
pouring the resin prefabricated liquid prepared in the step two into an iron mold, and pouring the resin prefabricated liquid on the graphene fiber membrane;
and then putting the iron mold into a flat vulcanizing machine, and carrying out curing reaction for 2 hours under the conditions of 1MPa pressure and 60 ℃ to obtain the chopped carbon fiber/graphene fiber/silicone rubber composite membrane.
Wherein the thickness of the composite film is 3mm, the content of the chopped carbon fibers is 0.001 wt%, and the content of the graphene is 0.5 wt%.
Example 5:
the preparation method of the electromagnetic shielding composite material of the embodiment specifically comprises the following steps:
preparation of graphene fiber membrane
By adopting a wet spinning process, under the thrust of an injection pump, 5mL of 3 wt% graphene oxide spinning aqueous solution is passed through a needle with the diameter of 110 mu m and 5 wt% calcium chloride aqueous solution to prepare the graphene oxide fiber. And spraying ethanol and performing vacuum drying to prepare the graphene oxide fiber membrane. And then, preparing the graphene fiber membrane by a reduction reaction at the ambient temperature of 60 ℃ and under the soaking of a hydriodic acid solution. And (3) repeatedly cleaning the graphene fiber membrane by using ethanol to remove redundant hydriodic acid and elemental iodine. Finally, ethanol and water were removed by vacuum drying to obtain a dried graphene fiber membrane.
Secondly, preparation of resin prefabricated liquid
100g of methyl vinyl polysiloxane, 30g of white carbon black, 10g of hydrogen-containing polysiloxane, 0.15g of platinum catalyst and 0.1g of inhibitor are blended and stirred to prepare the uncured silicone rubber liquid. Wherein the inhibitor is 1-ethynylcyclohexanol.
Mixing and stirring uncured 20g of silicone rubber liquid and 0.002g of chopped carbon fibers with the length of 6mm at a high speed, placing the mixture in a vacuum drying oven for defoaming after uniformly mixing, and preparing the resin prefabricated liquid.
Preparation of electromagnetic shielding composite material
Flatly paving the graphene fiber membrane prepared in the first step at the bottom of the iron mold; pouring the resin prefabricated liquid prepared in the step two into an iron mold, and pouring the resin prefabricated liquid on the graphene fiber membrane; and then putting the iron mold into a flat vulcanizing machine, and carrying out curing reaction for 2 hours under the conditions of 1MPa pressure and 60 ℃ to obtain the chopped carbon fiber/graphene fiber/silicone rubber composite membrane.
Wherein the thickness of the composite film is 3mm, the content of the chopped carbon fibers is 0.01 wt%, and the content of the graphene is 0.5 wt%.
Example 6:
the preparation method of the electromagnetic shielding composite material of the embodiment specifically comprises the following steps:
preparation of graphene fiber membrane
By adopting a wet spinning process, under the thrust of an injection pump, 5mL of 3 wt% graphene oxide spinning aqueous solution is passed through a needle with the diameter of 110 mu m and 5 wt% calcium chloride aqueous solution to prepare the graphene oxide fiber. And spraying ethanol and vacuum drying to obtain the graphene oxide fiber membrane. And then, preparing the graphene fiber membrane through a reduction reaction at the ambient temperature of 60 ℃ and under the soaking of a hydriodic acid solution. And (3) repeatedly cleaning the graphene fiber membrane by using ethanol to remove redundant hydriodic acid and elemental iodine. Finally, ethanol and water were removed by vacuum drying to obtain a dried graphene fiber membrane.
Secondly, preparation of resin prefabricated liquid
100g of methyl vinyl polysiloxane, 30g of white carbon black, 10g of hydrogen-containing polysiloxane, 0.15g of platinum catalyst and 0.1g of inhibitor are blended and stirred to prepare an uncured silicone rubber liquid. Wherein the inhibitor is 1-ethynylcyclohexanol.
Mixing and stirring uncured 20g of silicone rubber liquid and 0.01g of chopped carbon fibers with the length of 6mm at a high speed, placing the mixture in a vacuum drying oven for defoaming after uniformly mixing, and preparing the resin prefabricated liquid.
Preparation of electromagnetic shielding composite material
Flatly paving the graphene fiber membrane prepared in the first step at the bottom of the iron mold; pouring the resin prefabricated liquid prepared in the step two into an iron mold, and pouring the resin prefabricated liquid on the graphene fiber membrane; and then putting the iron mould into a flat vulcanizing machine, and carrying out curing reaction for 2 hours under the conditions of 1MPa pressure and 60 ℃ to obtain the chopped carbon fiber/graphene fiber/silicone rubber composite membrane. The thickness of the composite film is 3mm, wherein the content of the chopped carbon fibers is 0.05 wt%, and the content of the graphene is 0.5 wt%.
Comparative example 1:
comparative example 1 differs from example 1 in that: and a graphene fiber film is not added in the preparation process, so that the chopped carbon fiber/silicone rubber composite material is prepared.
Comparative example 2:
comparative example 2 differs from example 1 in that: short carbon fibers are not added in the preparation process, and the graphene fiber/silicon rubber composite material is prepared.
Comparative example 3:
comparative example 3 differs from example 1 in that: and directly blending and curing the chopped carbon fibers, the graphene fibers and the silicone rubber in the preparation process to prepare the graphene fiber/silicone rubber composite material.
Comparative example 4:
comparative example 4 differs from example 1 in that: the short carbon fibers are directly replaced by the carbon nanotubes in the preparation process, and the carbon nanotube/graphene fiber/silicone rubber composite material is prepared.
The results of the electromagnetic shielding effectiveness (X band) test for the composites prepared in each example and comparative example are shown in table 1.
TABLE 1 summary table of electromagnetic shielding effectiveness (X wave band)
From table 1, it can be seen that the composite material prepared by the invention has low-reflection electromagnetic shielding performance in the X frequency band. The performance test result of example 2 shows that too low graphene content leads to the decrease of the total shielding performance and the absorption coefficient is slightly decreased. The performance test result of example 3 shows that increasing the graphene content in the composite film can improve the total shielding performance, but the reflection coefficient can be greatly improved. The performance test results of examples 4, 5, 6 and comparative example 2 show that chopped carbon fibers are used as the absorption layer of the composite material, and the addition amount thereof has an important influence on the reflection coefficient and absorption coefficient of the composite film. In addition, suitable amounts of chopped carbon fibers can greatly reduce reflection of electromagnetic radiation. The reason for this is that the content of the chopped carbon fibers determines the impedance matching of the composite film.
The results of the electromagnetic shielding effectiveness (P-band) test on the composites prepared in each example and comparative example are shown in table 2.
TABLE 2 summary table of electromagnetic shielding effectiveness (P-band)
From the test results in table 2, it can be further seen that the electromagnetic shielding performance of the composite material prepared by the present invention is very obvious in the low reflection characteristic in the P frequency band. The performance test results of examples 1-6 show that the shielding mechanism of the composite film in the P frequency band is mainly absorption, and the reflection coefficient of the whole frequency band is less than 0.5. In example 5, the reflection coefficients in the P band are all less than 0.2, because the high frequency electromagnetic radiation has a higher penetration ability and is more likely to enter the composite film.
In the above embodiments and alternatives, the length of the chopped carbon fibers may also be 1mm, 3mm, 9mm, etc.
In the above embodiments and alternatives, the thickness of the composite film may also be 1mm, 2mm, 4mm, 5 mm.
In view of numerous embodiments of the present invention, all components, component contents, and process parameters can be determined in corresponding ranges according to application requirements, and experimental data of each embodiment is huge and numerous, and is not suitable for being enumerated and explained herein one by one, but contents required to be verified and final conclusions obtained in each embodiment are close to each other.
The foregoing has outlined rather broadly the preferred embodiments and principles of the present invention and it will be appreciated that those skilled in the art may devise variations of the present invention that are within the spirit and scope of the appended claims.
Claims (10)
1. The preparation method of the electromagnetic shielding composite material with the low reflection characteristic is characterized by comprising the following steps of:
firstly, flatly paving a graphene fiber film at the bottom of an iron mold;
mixing and stirring uncured silicone rubber liquid and short carbon fibers at a high speed, and placing the mixture in a vacuum drying oven for defoaming after uniform mixing;
pouring the defoamed short carbon fiber/silicone rubber premixed solution into an iron mold to pour the solution on the graphene fiber membrane;
and step four, placing the iron mold in a flat vulcanizing machine, and carrying out curing reaction to obtain the chopped carbon fiber/graphene fiber/silicone rubber composite membrane.
2. The preparation method of claim 1, wherein the graphene fiber membrane has an areal density of 2.5 to 40g/m 2 The diameter of each single graphene fiber is 30-50 mu m.
3. The method for preparing the silicone rubber composition according to claim 1, wherein the uncured silicone rubber liquid is formulated in the following parts by weight:
100 parts of methyl vinyl polysiloxane, 5-50 parts of white carbon black, 5-40 parts of hydrogen-containing polysiloxane, 0.05-0.5 part of platinum catalyst and 0.03-0.3 part of inhibitor.
4. The method of preparing according to claim 1, wherein the uncured silicone rubber liquid is blended with chopped carbon fibers in the following parts by weight:
100 parts of uncured silicone rubber liquid and 0.001-0.1 part of chopped carbon fiber.
5. The method according to claim 4, wherein the chopped carbon fibers have a length of 3 to 9mm, a diameter of 5 to 15 μm, and an electrical conductivity of 50000 to 100000S/m.
6. The preparation method according to claim 1, wherein the curing reaction temperature is 25-60 ℃, the curing reaction time is 2-6 h, and the curing reaction applied pressure is 0.001-1 MPa.
7. The electromagnetic shielding composite material prepared by the preparation method according to any one of claims 1 to 6, wherein the electromagnetic shielding composite material is a chopped carbon fiber/graphene fiber/silicone rubber composite film.
8. The electromagnetic shielding composite material as claimed in claim 7, wherein the chopped carbon fiber content in the chopped carbon fiber/graphene fiber/silicone rubber composite film is 0.001-0.1 wt%.
9. The electromagnetic shielding composite material as claimed in claim 7, wherein the graphene content in the chopped carbon fiber/graphene fiber/silicone rubber composite film is 0.1-1 wt%.
10. The electromagnetic shielding composite material as claimed in claim 7, wherein the chopped carbon fiber/graphene fiber/silicone rubber composite film has a thickness of 1-5 mm.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202210577905.XA CN115124843A (en) | 2022-05-25 | 2022-05-25 | Electromagnetic shielding composite material with low reflection characteristic and preparation method thereof |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202210577905.XA CN115124843A (en) | 2022-05-25 | 2022-05-25 | Electromagnetic shielding composite material with low reflection characteristic and preparation method thereof |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CN115124843A true CN115124843A (en) | 2022-09-30 |
Family
ID=83376325
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN202210577905.XA Pending CN115124843A (en) | 2022-05-25 | 2022-05-25 | Electromagnetic shielding composite material with low reflection characteristic and preparation method thereof |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN115124843A (en) |
Citations (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN102140186A (en) * | 2011-04-08 | 2011-08-03 | 青岛科技大学 | Natural rubber composite with electromagnetic shielding property and preparation method thereof |
| CN107283949A (en) * | 2016-04-01 | 2017-10-24 | 北京大学 | A kind of preparation of high electromagnet shield effect graphene/high polymer multilayer material |
| CN110282952A (en) * | 2019-06-25 | 2019-09-27 | 浙江理工大学 | The composite material and preparation method for having electromagnetic shielding and shape-memory properties |
| CN111996666A (en) * | 2020-09-08 | 2020-11-27 | 北京康烯科技创新研究有限公司 | Titanium nanosheet/graphene-based fiber membrane and preparation method thereof |
| US20210360838A1 (en) * | 2020-05-13 | 2021-11-18 | Get Green Energy Corp., Ltd. | Composite material for shielding or absorbing electromagnetic wave and method for manufacturing the same |
-
2022
- 2022-05-25 CN CN202210577905.XA patent/CN115124843A/en active Pending
Patent Citations (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN102140186A (en) * | 2011-04-08 | 2011-08-03 | 青岛科技大学 | Natural rubber composite with electromagnetic shielding property and preparation method thereof |
| CN107283949A (en) * | 2016-04-01 | 2017-10-24 | 北京大学 | A kind of preparation of high electromagnet shield effect graphene/high polymer multilayer material |
| CN110282952A (en) * | 2019-06-25 | 2019-09-27 | 浙江理工大学 | The composite material and preparation method for having electromagnetic shielding and shape-memory properties |
| US20210360838A1 (en) * | 2020-05-13 | 2021-11-18 | Get Green Energy Corp., Ltd. | Composite material for shielding or absorbing electromagnetic wave and method for manufacturing the same |
| CN111996666A (en) * | 2020-09-08 | 2020-11-27 | 北京康烯科技创新研究有限公司 | Titanium nanosheet/graphene-based fiber membrane and preparation method thereof |
Non-Patent Citations (1)
| Title |
|---|
| 芦浩浩: "EVA 基智能电磁屏蔽复合材料的制备及其性能" * |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| CN108165018B (en) | Silicone rubber/graphene/silver nanowire nano composite material for electromagnetic shielding and preparation method thereof | |
| CN108358541B (en) | Polypyrrole-coated graphene oxide cement-based composite material and preparation method thereof | |
| CN112203487B (en) | Heat-conducting wave-absorbing composite material and preparation method thereof | |
| CN108178930B (en) | Silicone rubber nanocomposite for electromagnetic shielding and preparation method thereof | |
| CN111534016B (en) | Electronic packaging material with heat conduction and electromagnetic shielding performance and preparation method thereof | |
| CN106366409B (en) | A kind of ultra-high molecular weight polyethylene/graphite alkene/nickel composite material and preparation method | |
| CN110903607A (en) | Preparation method of electromagnetic shielding composite material based on silver-plated carbon fiber | |
| CN108659467A (en) | The method of SiC/ graphene oxide compound modification of epoxy resin | |
| CN111269570A (en) | Preparation method of carbonized towel gourd/graphene-carbon nanotube composite material | |
| CN106317887A (en) | Polydopamine functionally modified high thermal conductive silicone rubber thermal interface material for LED and preparation method | |
| CN110172260A (en) | A kind of lightweight electromagnetic shielding sealing material and its preparation method and application | |
| CN110527491A (en) | A kind of electro-magnetic wave absorption and heat transfer composite material and preparation method | |
| CN115093226A (en) | High-strength multifunctional graphene elastomer foam and preparation method thereof | |
| CN115124843A (en) | Electromagnetic shielding composite material with low reflection characteristic and preparation method thereof | |
| CN110615877A (en) | Graft modified alumina, preparation method thereof, epoxy composite material and application thereof | |
| CN107123499A (en) | A kind of high-flexibility high temperature resistant electromagnetic noise suppresses piece and preparation method thereof | |
| CN109251434A (en) | A kind of preparation method of High Performance Shielding material | |
| CN110550870A (en) | surface treatment method of basalt scale fibers | |
| CN107089813B (en) | A kind of radiation-proof plate | |
| CN115073923A (en) | Low-specific-gravity high-heat-conductivity wave-absorbing gasket and preparation method thereof | |
| Habes et al. | Effective attenuation of electromagnetic waves via silane surface modified zinc oxide/polybenzoxazine nanocomposites for EMI shielding application | |
| Lala et al. | Effect of dual pre-treatment on mechanical, morphological, electrical and thermal properties of rubber seed shell-reinforced epoxy composites | |
| CN112047323A (en) | Carbonized grapefruit pulp @ silicon @ rGO natural electromagnetic shielding material and preparation method and application thereof | |
| CN114775330B (en) | Carbon fiber electromagnetic shielding paper and preparation method and application thereof | |
| CN105238344A (en) | Double-component anti-settle silicon-based wave absorption glue and preparation method thereof |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| PB01 | Publication | ||
| PB01 | Publication | ||
| SE01 | Entry into force of request for substantive examination | ||
| SE01 | Entry into force of request for substantive examination | ||
| RJ01 | Rejection of invention patent application after publication |
Application publication date: 20220930 |
|
| RJ01 | Rejection of invention patent application after publication |