CN112961389A - Flexible sleeve for electromagnetic shielding and preparation method thereof - Google Patents
Flexible sleeve for electromagnetic shielding and preparation method thereof Download PDFInfo
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- CN112961389A CN112961389A CN202110177603.9A CN202110177603A CN112961389A CN 112961389 A CN112961389 A CN 112961389A CN 202110177603 A CN202110177603 A CN 202110177603A CN 112961389 A CN112961389 A CN 112961389A
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- 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
- C08J7/00—Chemical treatment or coating of shaped articles made of macromolecular substances
- C08J7/04—Coating
- C08J7/044—Forming conductive coatings; Forming coatings having anti-static properties
-
- 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
- C08J7/00—Chemical treatment or coating of shaped articles made of macromolecular substances
- C08J7/04—Coating
- C08J7/06—Coating with compositions not containing macromolecular substances
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- 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
- C08J2323/00—Characterised by the use of homopolymers or copolymers of unsaturated aliphatic hydrocarbons having only one carbon-to-carbon double bond; Derivatives of such polymers
- C08J2323/02—Characterised by the use of homopolymers or copolymers of unsaturated aliphatic hydrocarbons having only one carbon-to-carbon double bond; Derivatives of such polymers not modified by chemical after treatment
- C08J2323/16—Ethene-propene or ethene-propene-diene copolymers
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- 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
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- 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
- C08J2383/08—Polysiloxanes containing silicon bound to organic groups containing atoms other than carbon, hydrogen, and oxygen
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- Chemical & Material Sciences (AREA)
- Health & Medical Sciences (AREA)
- Chemical Kinetics & Catalysis (AREA)
- Medicinal Chemistry (AREA)
- Polymers & Plastics (AREA)
- Organic Chemistry (AREA)
Abstract
The invention discloses a flexible sleeve for electromagnetic shielding and a preparation method thereof, belonging to the technical field of preparation of electromagnetic shielding materials. The preparation method comprises the following steps: coating the conductive coating on the inner surface of the rubber tube, the outer surface of the rubber tube and two ends of the rubber tube to form the rubber tube with the surface fully coated with the conductive coating, namely preparing the flexible sleeve for electromagnetic shielding; wherein the conductive coating comprises conductive particles. The coating can be prepared by one or more combined processes of a coextrusion method, a spraying method and a dipping method. The preparation method provided by the invention reduces the cost investment, solves the use defects of low overall strength, poor elasticity and poor toughness of the traditional conductive material, has excellent shielding efficiency, and improves the comprehensive mechanical property of the flexible sleeve for electromagnetic shielding.
Description
Technical Field
The invention belongs to the technical field of electromagnetic shielding material preparation, and particularly relates to a flexible sleeve for electromagnetic shielding and a preparation method thereof.
Background
With the widespread use of various electronic and electrical devices in society, electromagnetic waves have penetrated into the aspects of people's production and life as an important information carrier. However, as the energy of electromagnetic wave radiation increases day by day, a series of serious social and environmental problems are also caused. Therefore, there is a need for reducing or eliminating electromagnetic waves, and the use of electromagnetic shielding materials is one of the most effective methods.
The electromagnetic shielding material is generally conductive metal, but has the problems of heavy weight, high price, poor sealing performance and the like. In contrast, polymeric materials generally have a relatively low density and are widely appreciated by researchers. The conductive filler and the rubber are blended to enable the conductive particles to be contacted with each other in the rubber to form a three-dimensional network, so that the conductive rubber which has good conductive performance, excellent sealing performance and good mechanical performance is obtained, and the conductive rubber is widely applied to the fields of static resistance and electromagnetic shielding. The conductive silicone rubber is widely applied to the fields of electronics, electric power, war industry, aerospace, aviation and the like, and is used as a functional polymer type electromagnetic shielding material. The conductive silicone rubber sleeve is characterized in that a conductive particle is mixed with a polymer matrix material and then is processed and molded in practical application, and the conductive silicone rubber sleeve is limited by a structure prepared by processing the material, so that the conductive silicone rubber sleeve has the use defects of low mechanical strength, poor elasticity, poor toughness and the like, and cannot meet the use requirements of elasticity or toughness. Therefore, it is increasingly important to design and optimize the flexible sleeve.
Disclosure of Invention
In order to overcome the disadvantages of the prior art, the present invention provides a flexible bushing for electromagnetic shielding and a method for manufacturing the same, and provides an electromagnetic shielding bushing with excellent flexibility, which improves the mechanical properties of the electromagnetic shielding bushing in practical use.
In order to achieve the purpose, the invention adopts the following technical scheme to realize the purpose:
the invention discloses a preparation method of a flexible sleeve for electromagnetic shielding, which comprises the following steps: preparing a rubber tube by mixing and vulcanizing rubber and an auxiliary agent, and coating a conductive coating on the inner surface of the obtained rubber tube, the outer surface of the rubber tube and the end surface of the rubber tube to prepare a flexible sleeve for electromagnetic shielding; wherein the conductive coating comprises conductive particles.
Preferably, the conductive particles comprise one or a mixture of silver powder, nickel powder, copper powder, silver-coated aluminum powder, silver-coated copper powder, silver-coated glass beads, nickel-coated aluminum powder or nickel-coated graphite powder.
Further preferably, the silver content in the silver-coated aluminum powder, the silver-coated copper powder, the silver-coated glass beads, the nickel-coated aluminum powder or the nickel-coated graphite powder is 10-60%, and the nickel content is 60-80%.
Preferably, the conductive particles have a particle size of 0.01 to 50 microns.
Preferably, the rubber comprises silicone rubber, fluorosilicone rubber, or ethylene propylene rubber.
Preferably, the coating is prepared by a spraying method, and specifically comprises the following operations: 1) extruding and molding the rubber dispersed with the auxiliary agent to obtain a rubber tube; spraying conductive particles on the inner surface of the rubber tube by using an inner spray gun to form an inner coating, and spraying conductive particles on the outer surface of the rubber tube by using an outer spray gun to form an outer coating to prepare a coated rubber tube by using an electrostatic plastic spraying technology; 2) the obtained rubber tube with the surface fully coated with the conductive coating is baked, leveled and cured at high temperature to obtain an inner surface and outer surface coated rubber tube; 3) and spraying conductive particles on the end faces of the obtained inner and outer surface-coated rubber tubes by using an outer spray gun to form the rubber tubes with the surfaces fully coated with the conductive coatings, namely manufacturing the flexible sleeve for electromagnetic shielding.
Further preferably, the electrostatic spraying technology is adopted, and the working parameters comprise: the electrostatic high voltage is 60-90 kV, the electrostatic current is 10-20 muA, the flow velocity pressure is 0.30-0.55 MPa, the atomization pressure is 0.30-0.45 MPa, the gun cleaning pressure is 0.4-0.5 MPa, the fluidization pressure of a powder supply barrel is 0.04-0.10 MPa, and the powder output is 500-600 g/min.
Preferably, the preparation method adopts a full immersion method, and specifically comprises the following operations: extruding and molding the rubber dispersed with the auxiliary agent to obtain a rubber tube; and (3) dipping the obtained rubber tube in a conductive particle dipping solution, and then curing to form the rubber tube with the surface fully coated with the conductive coating, namely the flexible sleeve for electromagnetic shielding is prepared.
Preferably, the method is a coextrusion method, and specifically comprises the following operations: 1) respectively filling the conductive slurry into two extruders by a co-extrusion technology, filling the rubber dispersed with the auxiliary agent into one extruder, extruding and molding the three extruders through a co-extrusion die, fusing and adhering the conductive coating with the inner surface of the rubber tube and the outer surface of the rubber tube at the same time in the co-extrusion die to prepare a composite sleeve, and carrying out high-temperature sizing sleeve on the obtained composite sleeve to prepare the rubber sleeve with the inner surface and the outer surface coated with the conductive coating; 2) and placing the obtained rubber sleeve with the inner surface and the outer surface coated with the conductive coating in conductive particle immersion liquid, coating the exposed structures at two ends to form a rubber tube with the surface fully coated with the conductive coating, and curing to obtain the flexible sleeve for electromagnetic shielding.
The invention also discloses a flexible sleeve for electromagnetic shielding, which is prepared by the preparation method.
Compared with the prior art, the invention has the following beneficial effects:
the invention discloses a preparation method of a flexible sleeve for electromagnetic shielding, which comprises the steps of coating a conductive coating containing conductive particles on the inner surface of a rubber tube, the outer surface of the rubber tube and the end faces of the rubber tube at two ends of the rubber tube to form the rubber tube with the surface fully coated with the conductive coating, thus obtaining the flexible sleeve for electromagnetic shielding; compared with the traditional electromagnetic shielding conductive rubber, the preparation method avoids the preparation method of using the conductive filler and the rubber base material to be mixed and then molded, thereby avoiding the problem that the molded material has more mechanical defects. According to the invention, the conductive coating is formed by adopting the conductive particles, so that the use defects of large addition amount of the original conductive filler, low mechanical strength, poor elasticity, poor toughness and the like can be overcome, the coated rubber tube substrate is combined, the rubber tube provides a flexible structure of the flexible sleeve integrally used for electromagnetic shielding, and the conductive coating forms an electromagnetic shielding structure, so that the conductive rubber composite sleeve with high conductivity and high electromagnetic shielding is prepared. Therefore, the preparation method disclosed by the invention has the advantages of effectively reducing the cost investment, being simple and efficient in preparation process and being capable of being popularized in industrial production.
Furthermore, the conductive filler comprises silver-coated aluminum powder, silver-coated copper powder, silver-coated glass beads, nickel-coated aluminum powder or nickel-coated graphite powder, and the problems of high density, poor comprehensive performance, limited filling amount and the like of the traditional filler can be solved while the electromagnetic shielding effect is ensured.
Furthermore, the preparation method is suitable for various conductive particles, and different filler types can be selected according to the cost requirement, so that the cost input is effectively controlled.
Furthermore, the conductive particles can be matched with different base materials by regulating the particle size of the conductive particles, so that good bonding force is obtained and the conductive particles do not fall off.
Furthermore, the preparation method can be applied to different rubber materials, and has strong adaptability.
Furthermore, the invention can adopt different coating process methods for production and preparation, combines different production fields, and has wide application range.
The invention also discloses the flexible sleeve for electromagnetic shielding prepared by the preparation method, wherein the flexible sleeve for electromagnetic shielding takes a rubber tube prepared by mixing rubber as a matrix, and the inner surface and the outer surface of the rubber tube and two ends of the rubber tube are coated with conductive coatings. Relevant tests show that the flexible sleeve for electromagnetic shielding has excellent shielding efficiency, improves the comprehensive mechanical property of the electromagnetic shielding sleeve in actual use, and can be widely applied to electronic equipment for military use, aerospace, aviation and the like.
Drawings
FIG. 1 is a schematic radial cross-sectional view of a flexible sleeve for electromagnetic shielding in accordance with the present invention;
fig. 2 is an axial sectional view of a flexible bushing for electromagnetic shielding according to the present invention.
Wherein, 1-conductive coating; 2-base body.
Detailed Description
In order to make the technical solutions of the present invention better understood, 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.
It should be noted that the terms "first," "second," and the like in the description and claims of the present invention and in the drawings described above are used for distinguishing between similar elements and not necessarily for describing a particular sequential or chronological order. It is to be understood that the data so used is interchangeable under appropriate circumstances such that the embodiments of the invention described herein are capable of operation in sequences other than those illustrated or described herein. Furthermore, the terms "comprises," "comprising," and "having," and any variations thereof, are intended to cover a non-exclusive inclusion, such that a process, method, system, article, or apparatus that comprises a list of steps or elements is not necessarily limited to those steps or elements expressly listed, but may include other steps or elements not expressly listed or inherent to such process, method, article, or apparatus.
The invention discloses a flexible sleeve for electromagnetic shielding, which is prepared by taking rubber as a main base material, taking a cross-linking agent, a reinforcing agent, an anti-aging agent and the like as auxiliary agents, and preparing conductive particles consisting of one or a mixture of more of silver powder, nickel powder, copper powder, silver-coated aluminum powder, silver-coated copper powder, silver-plated glass beads, nickel-coated aluminum powder or nickel-coated graphite powder and the like into conductive paste, and then curing the conductive paste to be used as a conductive coating, and forming a rubber tube with the surface fully coated with the conductive coating through a reasonable processing technology.
Wherein, the silver content in the silver-coated aluminum powder, the silver-coated copper powder, the silver-coated glass beads, the nickel-coated aluminum powder or the nickel-coated graphite powder is 10 to 60 percent, and the nickel content is 60 to 80 percent; wherein the rubber comprises silicon rubber, fluorosilicone rubber or ethylene propylene rubber.
Wherein the particle size of the silver powder, the nickel powder, the copper powder, the silver-coated aluminum powder, the silver-coated copper powder, the silver-coated glass beads, the nickel-coated aluminum powder or the nickel-coated graphite powder is 0.01-50 microns.
Wherein the rubber accounts for 30-60 parts by mass, and the conductive particles account for 30-80 parts by mass; 0.5-5 parts of cross-linking agent, 1-15 parts of reinforcing agent and 0.5-10 parts of anti-aging agent.
Specifically, in one embodiment of the present invention, the rubber includes silicone rubber, fluorosilicone rubber, ethylene propylene rubber, or the like; the cross-linking agent is one of dicumyl peroxide (DCP), Benzoyl Peroxide (BPO), di-tert-butyl peroxide (DTBP) and 2, 5-dimethyl-2, 5-di-tert-butyl hexane peroxide; the reinforcing agent is one of carbon black and white carbon black; the anti-aging agent is one of anti-aging agent D, anti-aging agent RD, anti-aging agent 124 and anti-aging agent MB.
The flexible sleeve for electromagnetic shielding can be prepared by one or more combined processes of a coextrusion method, a spraying method and a dipping method, and specifically comprises the following steps:
Adding the rubber with the dispersed auxiliary agent into a feeding machine, and blending, extruding and molding the rubber and the auxiliary agent by using an extruder to prepare a rubber tube; the electrostatic spraying machine is installed inside and outside the rubber tube, then the conductive particles are loaded in the electrostatic spraying machine, the conductive particle powder is in a fluidized state through compressed air, the conductive particle powder is carried by airflow flowing at high speed through siphonage to form powder-air mixture, and finally the powder-air mixture reaches the spray gun through the Venturi powder pump and the powder conveying tube, and the spray gun comprises an inner spray gun and an outer spray gun, so that the conductive particles are coated inside and outside the rubber sleeve. And installing rollers at the ports, enabling the extruded rubber tube to continuously rotate in the spraying process, enabling the conductive particles to be uniformly sprayed, enabling conductive particle powder to be uniformly adsorbed on the surface of the rubber tube under the action of static electricity to form a powdery conductive coating, baking, leveling and curing at a high temperature to obtain an inner surface and outer surface coated rubber sleeve, cutting the inner surface and outer surface coated rubber sleeve into required lengths by using a coiler or a cutting machine, finally placing the cut inner surface and outer surface coated rubber sleeve on a positioning device aiming at the exposed end face generated after cutting, and continuously performing static spraying to enable the exposed parts at the two ends of the inner surface and outer surface coated rubber sleeve to be coated with the conductive coating, thereby obtaining the rubber tube with the surface completely coated with the conductive coating, namely obtaining the flexible sleeve for electromagnetic shielding.
Specifically, the diameter of the excircle of the rubber tube is 0.5 mm-10 mm, the diameter of the inner hole is 0.3 mm-6 mm, and the single length of the rubber tube is 1 mm-30 mm.
Specifically, the number of the spray guns is determined according to conditions, and in principle, the more spray guns are, the powder discharge amount is small, the powder charging rate is high, the powder feeding rate is high, the effect is better, the number of the spray guns is generally 4-6, and the diameter of a nozzle is generally 1.0-3.0 mm;
powder electrostatic spraying parameter setting: the electrostatic high voltage is 60-90 kV, the electrostatic current is 10-20 muA, the flow velocity pressure is 0.30-0.55 MPa, the atomization pressure is 0.30-0.45 MPa, the gun cleaning pressure is 0.4-0.5 MPa, the fluidization pressure of a powder supply barrel is 0.04-0.10 MPa, and the powder output is 500-600 g/min.
The high-temperature baking leveling curing temperature is 80-120 ℃, and the curing time is 30-45 min.
The rubber is put into an extruder, the auxiliary agent is added into the extruder, the rubber with the dispersed auxiliary agent is extruded and molded to obtain a rubber tube, then the rubber tube is cut into required length by a coiler or a cutting machine, then the rubber tube cut according to the size is put into the conductive particle impregnation liquid for impregnation for a certain time, and then the rubber tube is taken out for curing to form the rubber tube with the surface fully coated with the conductive coating, thus obtaining the flexible sleeve for electromagnetic shielding.
Specifically, the outer diameter of the rubber tube is 0.5 mm-10 mm, the inner diameter is 0.3 mm-6 mm, and the single length of the rubber tube is 1 mm-30 mm.
The conductive particle dipping solution comprises deionized water, alcohols, toluene, xylene and the like, and the dipping time is 20min to 40 min; specifically, in the conductive particle dipping solution, by mass, the parts of deionized water/conductive particles is 0.5-0.85, the parts of alcohols are 0.2-0.5 of the parts of deionized water, and the parts of toluene and xylene are 0.1-0.3 of the parts of deionized water.
The curing temperature is 60-80 ℃, and the curing time is 2-4 h.
Method 3 Co-extrusion
The method comprises the steps of respectively loading conductive particles into two extruders through a coextrusion production process technology, simultaneously feeding rubber into the other extruder, adding required auxiliaries into the extruder, then enabling extrusion materials of the three extruders to pass through a coextrusion opening die, finishing fusion adhesion of a conductive coating inside the coextrusion opening die and the inner surface of a rubber pipe and the outer surface of the rubber pipe to form a composite sleeve, continuously passing the composite sleeve through a high-temperature sizing sleeve, cutting the composite sleeve into required lengths through a coiling machine or a cutting machine, then placing the composite sleeve into an impregnation tank filled with conductive particle impregnation liquid, enabling the exposed parts at two ends of the composite sleeve to be coated with the conductive coating, curing to obtain the flexible sleeve which is internally provided with the rubber and is completely coated with the conductive coating on the surface and used for electromagnetic shielding.
Specifically, the diameter of the excircle of the rubber tube is 0.5 mm-10 mm, the diameter of the inner hole is 0.3 mm-6 mm, and the single length of the rubber tube is 1 mm-30 mm.
The conductive particle impregnation liquid in the impregnation tank comprises deionized water, alcohols, toluene, xylene and the like, and the impregnation time is 20-40 min; specifically, in the conductive particle immersion liquid, the mass portion of deionized water/the mass portion of conductive particles is 0.5-0.85; the adding parts of the alcohols are 0.2-0.5 part of the deionized water, and the adding parts of the methylbenzene and the dimethylbenzene are 0.1-0.3 part of the deionized water.
The curing temperature is 60-80 ℃, and the curing time is 2-4 h.
The present invention will be described in detail with reference to the following specific examples:
example 1
The invention relates to a preparation method of a flexible sleeve for electromagnetic shielding, which is implemented according to the following steps:
is prepared by a spraying method
Weighing 60 parts of methyl vinyl silicone rubber, 6 parts of an anti-aging agent RD, 3 parts of dicumyl peroxide (DCP) and 2 parts of white carbon black, adding into a feeder, setting the excircle diameter of a rubber tube to be 10mm and the inner hole diameter to be 6mm, and extruding and molding rubber by using an extruder; weighing 80 parts of silver-coated aluminum powder (the silver content is 45%), the average particle size of the silver-coated aluminum powder is 50 μm, dividing the silver-coated aluminum powder into four parts, and respectively filling the four parts into inner spray guns and outer spray guns (two inner spray guns and two outer spray guns); the diameter of the nozzle is 1mm, the electrostatic high voltage is 80kV, the electrostatic current is 15 muA, the flow velocity pressure is 0.45MPa, the atomization pressure is 0.40MPa, the gun cleaning pressure is 0.5MPa, the fluidization pressure of a powder supply barrel is 0.08MPa, and the powder output is 500 g/min; enabling the silver-coated aluminum powder to be in a fluidized state through compressed air, forming a coating on the surface of the rubber sleeve by using a spray gun, baking the coating at a high temperature, leveling and curing to obtain the rubber sleeve with the outer surface coated, and curing for 45min at 80 ℃; cutting the rubber sleeve into rubber sleeves with the length of 5mm by using a coiler or a cutting machine, placing the rubber sleeves coated on the inner and outer surfaces after cutting on a positioning device aiming at the exposed end surfaces generated after cutting, and continuously performing electrostatic spraying to ensure that the exposed parts at the two ends of the rubber sleeves are coated with conductive fillers to prepare the flexible sleeve for electromagnetic shielding.
Example 2
Is prepared by a spraying method
Weighing 40 parts of methyl vinyl silicone rubber, 6 parts of an anti-aging agent RD, 3 parts of dicumyl peroxide (DCP) and 2 parts of white carbon black, adding into a feeder, setting the excircle diameter of a rubber tube to be 5mm and the inner hole diameter to be 3mm, and extruding and molding rubber by using an extruder; weighing 30 parts of silver powder with the average particle size of 0.01 mu m, dividing the silver powder into four parts, and respectively filling the four parts into an inner spray gun and an outer spray gun (two inner spray guns and two outer spray guns); the diameter of the nozzle is 1mm, the electrostatic high voltage is 80kV, the electrostatic current is 15 muA, the flow velocity pressure is 0.45MPa, the atomization pressure is 0.40MPa, the gun cleaning pressure is 0.5MPa, the fluidization pressure of a powder supply barrel is 0.08MPa, and the powder output is 600 g/min; the silver powder is in a fluidized state by compressed air, a coating is formed on the surface of the rubber sleeve by a spray gun, the coating is baked, leveled and cured at high temperature to obtain the rubber sleeve with the outer surface coated, and the curing is carried out for 45min at 80 ℃; cutting the rubber sleeve into 6mm rubber sleeves by a coiler or a cutting machine, placing the cut rubber sleeves coated on the inner and outer surfaces of the rubber sleeves on a positioning device aiming at the exposed end surfaces generated after cutting, and continuously performing electrostatic spraying to ensure that the exposed parts at the two ends of the rubber sleeves are coated with conductive fillers to prepare the flexible sleeve for electromagnetic shielding.
Example 3
Is prepared by a spraying method
Weighing 30 parts of methyl vinyl silicone rubber, 6 parts of an anti-aging agent RD, 3 parts of dicumyl peroxide (DCP) and 2 parts of white carbon black, adding into a feeder, setting the outer circle diameter of a rubber tube to be 0.5mm and the inner hole diameter to be 0.3mm, and extruding and molding rubber by using an extruder; weighing 40 parts of nickel powder, dividing the nickel powder into four parts, and respectively filling the four parts into an inner spray gun and an outer spray gun (two inner spray guns and two outer spray guns); the diameter of the nozzle is 1mm, the electrostatic high voltage is 80kV, the electrostatic current is 15 muA, the flow velocity pressure is 0.45MPa, the atomization pressure is 0.40MPa, the gun cleaning pressure is 0.5MPa, the fluidization pressure of a powder supply barrel is 0.08MPa, and the powder output is 560 g/min; the nickel powder enables the powder to be in a fluidized state through compressed air, a coating is formed on the surface of the rubber sleeve by using a spray gun, the coating is baked, leveled and cured at high temperature to obtain the rubber sleeve with the outer surface coated, and the high curing is carried out for 45min at 80 ℃; cutting the rubber sleeve into rubber sleeves with the length of 1mm by using a coiler or a cutting machine, placing the rubber sleeves coated on the inner and outer surfaces after cutting on a positioning device aiming at the exposed end surfaces generated after cutting, and continuously performing electrostatic spraying to ensure that the exposed parts at the two ends of the rubber sleeves are coated with conductive fillers to prepare the flexible sleeve for electromagnetic shielding.
Example 4
Is prepared by a spraying method
Weighing 45 parts of ethylene propylene rubber, 0.5 part of anti-aging agent 124, 3 parts of hydrogen peroxide diisopropylbenzene and 2 parts of carbon black, adding into a feeder, setting the diameter of the outer circle of a rubber tube to be 1mm and the diameter of an inner hole to be 0.5mm, and extruding and molding the rubber by using an extruder; weighing 50 parts of silver-plated glass beads (the silver content is 10%), the average grain diameter of the silver-plated glass beads is 10 micrometers, dividing the silver-plated glass beads into five parts, and respectively filling the five parts into inner spray guns and outer spray guns (two inner spray guns and three outer spray guns); the diameter of the nozzle is 3mm, the electrostatic high voltage is 60kV, the electrostatic current is 10 muA, the flow velocity pressure is 0.30MPa, the atomization pressure is 0.30MPa, the gun cleaning pressure is 0.45MPa, the fluidization pressure of a powder supply barrel is 0.04MPa, and the powder output is 530 g/min; the silver powder is in a fluidized state by compressed air, a coating is formed on the surface of the rubber sleeve by a spray gun, the coating is baked, leveled and cured at high temperature to obtain the rubber sleeve with the outer surface coated, and the high curing is carried out for 30min at 120 ℃; cutting the rubber sleeve into rubber sleeves with the length of 15mm by using a coiler or a cutting machine, placing the rubber sleeves coated on the inner and outer surfaces after cutting on a positioning device aiming at the exposed end surfaces generated after cutting, and continuously performing electrostatic spraying to ensure that the exposed parts at the two ends of the rubber sleeves are coated with conductive fillers to prepare the flexible sleeve for electromagnetic shielding.
Example 5
Is prepared by a spraying method
Weighing 50 parts of ethylene propylene rubber, 10 parts of an antioxidant MB, 0.5 part of di-tert-butyl peroxide (DTBP) and 15 parts of carbon black, adding into a feeder, setting the diameter of the outer circle of a rubber tube to be 7mm and the diameter of an inner hole to be 4mm, and extruding and molding the rubber by using an extruder; weighing 66 parts of nickel-coated graphite powder (the nickel content is 60 percent), equally dividing the nickel-coated graphite powder into six parts, and respectively filling the six parts into inner spray guns and outer spray guns (three inner spray guns and three outer spray guns); the diameter of the nozzle is 2mm, the electrostatic high voltage is 90kV, the electrostatic current is 20 muA, the flow velocity pressure is 0.55MPa, the atomization pressure is 0.45MPa, the gun cleaning pressure is 0.40MPa, the fluidization pressure of a powder supply barrel is 0.10MPa, and the powder output is 580 g/min; the silver powder is in a fluidized state by compressed air, a coating is formed on the surface of the rubber sleeve by a spray gun, the coating is baked, leveled and cured at high temperature to obtain the rubber sleeve with the outer surface coated, and the high curing is carried out for 35min at 100 ℃; cutting the rubber sleeve into rubber sleeves with the length of 30mm by using a coiler or a cutting machine, placing the rubber sleeves coated on the inner and outer surfaces after cutting on a positioning device aiming at the exposed end surfaces generated after cutting, and continuously performing electrostatic spraying to ensure that the exposed parts at the two ends of the rubber sleeves are coated with conductive fillers to prepare the flexible sleeve for electromagnetic shielding.
Example 6
Prepared by full immersion method
Weighing 30 parts of fluorosilicone rubber, filling the fluorosilicone rubber into an extruder, adding 5 parts of an anti-aging agent 124, 3 parts of white carbon black and 2 parts of Benzoyl Peroxide (BPO) into a feeder, performing extrusion molding to obtain a rubber tube, setting the outer circle diameter of the rubber tube to be 2mm and the inner hole diameter to be 1mm, and then cutting the rubber tube into rubber tubes with the length of 6mm by using a coiler or a cutting machine; and then weighing 30 parts of silver powder (with the average particle size of 10 microns) and putting the silver powder into a dipping tank, adding 15 parts of deionized water, 7.5 parts of ethanol and 4.5 parts of dimethylbenzene, then putting a rubber tube cut according to the size into the dipping tank, dipping for 30min, taking out and curing at the temperature of 80 ℃ for 2h to obtain the flexible conductive sleeve, and thus obtaining the flexible conductive sleeve for electromagnetic shielding.
Example 7
Prepared by full immersion method
Weighing 60 parts of fluorosilicone rubber, filling the fluorosilicone rubber into an extruder, adding 5 parts of an anti-aging agent 124, 3 parts of white carbon black and 0.5 part of 2, 5-dimethyl-2, 5-di-tert-butyl hexane peroxide into a feeder, performing extrusion molding to obtain a rubber tube, setting the diameter of the outer circle of the rubber tube to be 10mm, setting the diameter of the inner hole of the rubber tube to be 6mm, and then cutting the rubber tube into a rubber tube with the length of 30mm by using a tube coiling machine or a cutting machine; and then weighing 80 parts of copper powder (with the average particle size of 50 microns) and putting the copper powder into a dipping tank, adding 40 parts of deionized water, 16 parts of ethanol and 8 parts of xylene, then putting a rubber tube cut according to the size into the dipping tank, dipping the rubber tube for 30min, taking out the rubber tube and curing the rubber tube at the temperature of 80 ℃ for 2h to obtain the flexible conductive sleeve, namely the flexible conductive sleeve for electromagnetic shielding is prepared.
Example 8
Prepared by full immersion method
Weighing 45 parts of fluorosilicone rubber, filling the fluorosilicone rubber into an extruder, adding 5 parts of an anti-aging agent 124, 3 parts of white carbon black and 5 parts of dicumyl peroxide (DCP) into a feeder, performing extrusion molding to obtain a rubber tube, wherein the diameter of the outer circle of the rubber tube is set to be 0.5mm, the diameter of the inner hole of the rubber tube is 0.3mm, and then cutting the rubber tube into a rubber tube with the length of 15mm by using a coiling machine or a cutting machine; then, 65 parts of silver-coated copper powder (with the silver content of 60%) (the average particle size of 35 microns) is weighed and placed into a dipping tank, 39 parts of deionized water, 15.6 parts of ethanol and 7.8 parts of dimethylbenzene are added, then a rubber tube cut according to the size is placed into the dipping tank, dipping is carried out for 30min, the rubber tube is taken out and cured, the temperature is 80 ℃, and the curing time is 2 hours, so that the flexible conductive sleeve is obtained, and the flexible sleeve for electromagnetic shielding is obtained.
Example 9
Prepared by full immersion method
Weighing 50 parts of ethylene propylene rubber, filling the ethylene propylene rubber into an extruder, adding 10 parts of an anti-aging agent D, 1 part of carbon black and 0.5 part of Benzoyl Peroxide (BPO) into a feeder, performing extrusion molding to obtain a rubber tube, setting the diameter of the outer circle of the rubber tube to be 6mm and the diameter of the inner hole to be 5mm, and then cutting the rubber tube into rubber tubes with the length of 3mm by using a coiler or a cutting machine; then, 50 parts of nickel-coated aluminum powder (the nickel content is 80%) (the average particle size is 1 micron) is weighed and placed into a dipping tank, 42.5 parts of deionized water, 8.5 parts of methanol and 4.25 parts of toluene are added, then a rubber tube cut according to the size is placed into the dipping tank, dipping is carried out for 20min, the rubber tube is taken out and cured at the temperature of 60 ℃ for 4h, and the flexible conductive sleeve is obtained, namely the flexible sleeve for electromagnetic shielding is prepared.
Example 10
Prepared by full immersion method
Weighing 35 parts of methyl vinyl silicone rubber, filling the methyl vinyl silicone rubber into an extruder, adding 0.5 part of an anti-aging agent MB, 15 parts of carbon black and 5 parts of di-tert-butyl peroxide (DTBP) into a feeder, performing extrusion molding to obtain a rubber tube, setting the diameter of the outer circle of the rubber tube to be 1mm and the diameter of the inner hole to be 0.3mm, and then cutting the rubber tube into a rubber sleeve with the length of 1mm by using a coiler or a cutting machine; then, 40 parts of nickel-coated aluminum powder (with the average particle size of 0.01 microns) (the nickel content of 70%) is weighed and placed into a dipping tank, 28 parts of deionized water, 8.4 parts of hexanediol and 5.6 parts of toluene are added, then the rubber sleeve cut according to the size is placed into the dipping tank, dipping is carried out for 40min, the rubber sleeve is taken out and solidified, the temperature is 70 ℃, and the solidifying time is 3 hours, so that the flexible conductive sleeve for electromagnetic shielding is obtained, and the flexible sleeve for electromagnetic shielding is obtained.
Example 11
Prepared by coextrusion method
Weighing two groups of 15 parts of silver-plated glass beads (the silver content is 25%) (the average particle size is 5 microns), respectively and uniformly dispersing the two groups of silver-plated glass beads in silicone oil to obtain conductive slurry (the feeding mass ratio of the silver-plated glass beads to the silicone oil is 50: 10), respectively feeding the conductive slurry into two extruders, simultaneously weighing 30 parts of ethylene propylene rubber, feeding the ethylene propylene rubber into another extruder, adding 7 parts of an anti-aging agent MB, 4 parts of dicumyl peroxide and 3 parts of a reinforcing agent white carbon black, then passing the materials of the three extruders through a co-extrusion die, completing fusion and adhesion in the die to form a composite sleeve, passing through a high-temperature sizing sleeve, setting the diameter of an inner hole to be 0.5mm and the diameter of an outer circle to be 1mm, then carrying out curing, setting the curing temperature to be 75 ℃ and the curing time to be 3 hours, then cutting the composite sleeve into a rubber sleeve with the length of 1, placing the flexible sleeve into a dipping tank filled with silver-plated glass bead dipping liquid, wherein the dipping time is 30min, so that the exposed parts at the two ends of the flexible sleeve are also coated with conductive fillers to obtain the flexible sleeve with the inside being rubber and the surface being fully coated with the conductive fillers, and the flexible sleeve for electromagnetic shielding is prepared.
The silver-plated glass bead immersion liquid is filled with 0.8 part of deionized water/0.45 part of silver-plated glass beads, and 0.15 part of dimethylbenzene.
Example 12
Prepared by coextrusion method
Weighing two groups of 40 parts of nickel-coated graphite powder (the nickel content is 65%) (the average particle size is 0.01 mu m), respectively and uniformly dispersing the two groups of nickel-coated graphite powder in silicone oil to obtain conductive slurry (the feeding mass ratio of the nickel-coated graphite powder to the silicone oil is 90: 50), respectively feeding the conductive slurry into two extruders, simultaneously weighing 45 parts of ethylene propylene rubber, feeding the ethylene propylene rubber into another extruder, adding 7 parts of an anti-aging agent MB, 4 parts of hydrogen peroxide diisopropylbenzene and 3 parts of a reinforcing agent white carbon black, then passing the materials of the three extruders through a co-extrusion die, completing fusion and adhesion in the die to form a composite sleeve, passing through a high-temperature sizing sleeve, setting the inner hole diameter to be 5mm and the outer circle diameter to be 7mm, then curing, setting the curing temperature to be 75 ℃ and the curing time to be 3h, then cutting the composite sleeve into a rubber sleeve with the length of 20mm by using a coiling machine or a cutting machine, placing the rubber sleeve into a dipping tank filled with, and (3) soaking for 30min, so that the exposed parts at the two ends of the flexible sleeve are also coated with the conductive filler to obtain the flexible sleeve with the rubber inside and the conductive filler completely coated on the surface, and thus the flexible sleeve for electromagnetic shielding is prepared.
The nickel-coated graphite powder dipping solution is filled with 0.85 part of deionized water/0.2 part of nickel-coated graphite powder, and 0.3 part of deionized water.
Example 13
Prepared by coextrusion method
Weighing two groups of 325 parts of nickel-coated aluminum powder (the nickel content is 75%) (the average particle size is 20 microns), respectively and uniformly dispersing the two groups of nickel-coated aluminum powder in silicone oil to obtain conductive slurry (the feeding mass ratio of the nickel-coated aluminum powder to the silicone oil is 60: 20), respectively feeding the conductive slurry into two extruders, simultaneously weighing 40 parts of ethylene propylene rubber, feeding the ethylene propylene rubber into the other extruder, adding 7 parts of an anti-aging agent MB, 4 parts of dicumyl peroxide and 3 parts of a reinforcing agent white carbon black, then passing the materials of the three extruders through a co-extrusion die, completing fusion and adhesion in the die to form a composite sleeve, passing through a high-temperature sizing sleeve, setting the diameter of an inner hole to be 1mm and the diameter of an outer circle to be 3mm, then curing, setting the curing temperature to be 75 ℃ and the curing time to be 3 hours, then cutting the composite sleeve into a rubber sleeve with the length of 15mm by using a coiler or a cutting machine, placing the rubber, and (3) soaking for 30min, so that the exposed parts at the two ends of the flexible sleeve are also coated with the conductive filler to obtain the flexible sleeve with the rubber inside and the conductive filler completely coated on the surface, and thus the flexible sleeve for electromagnetic shielding is prepared.
The nickel-coated aluminum powder dipping solution is filled, the deionized water part/nickel-coated aluminum powder part is 0.5, the methanol adding part is 0.5 of the deionized water part, and the xylene adding part is 0.1 of the deionized water part. (inner diameter)
Example 14
Prepared by coextrusion method
Weighing two groups of 25 parts of copper powder (the average particle size is 50 mu m), respectively and uniformly dispersing the two groups of copper powder in silicon oil to obtain conductive slurry (the feeding mass ratio of the copper powder to the silicon oil is 70: 30), then respectively loading the conductive slurry into two extruders, simultaneously weighing 50 parts of ethylene propylene rubber, feeding the ethylene propylene rubber into the other extruder, adding 0.5 part of anti-aging agent 124, 0.5 part of hydrogen peroxide diisopropylbenzene and 15 parts of reinforcing agent carbon black into the conductive slurry, then enabling the materials of the three extruders to pass through a co-extrusion die, completing fusion and adhesion in the die to form a composite sleeve, passing through a high-temperature sizing sleeve, setting the diameter of an inner hole to be 0.3mm and the diameter of an outer circle to be 0.5mm, then carrying out curing at the curing temperature of 60 ℃ for 4h, then cutting the composite sleeve into a rubber sleeve with the length of 6mm by using a coiler or a cutting machine, placing the rubber sleeve into an impregnation tank filled with the copper powder, and coating the exposed parts at the two ends with the conductive filler to obtain the flexible sleeve with the rubber inside and the conductive filler completely coated on the surface, thereby obtaining the flexible sleeve for electromagnetic shielding.
The copper powder impregnation liquid is filled with 0.7 part of deionized water/0.3 part of copper powder, 0.2 part of ethanol and 0.2 part of deionized water.
Example 15
Prepared by coextrusion method
Weighing two groups of 20 parts of nickel-coated aluminum powder (the nickel content is 70%) (the average particle size is 0.05 mu m), respectively and uniformly dispersing the two groups of nickel-coated aluminum powder in silicone oil to obtain conductive slurry (the feeding mass ratio of the nickel-coated aluminum powder to the silicone oil is 80: 40), respectively feeding the conductive slurry into two extruders, simultaneously weighing 60 parts of ethylene propylene rubber, feeding the ethylene propylene rubber into another extruder, adding 10 parts of an anti-aging agent RD, 5-dimethyl-2, 5-di-tert-butyl hexane peroxide and 1 part of reinforcing agent carbon black, allowing the materials of the three extruders to pass through a co-extrusion die, fusing and adhering the materials in the die to form a composite sleeve, allowing the composite sleeve to pass through a high-temperature sizing sleeve, setting the inner hole diameter to be 6mm, setting the outer circle diameter to be 10mm, curing at the curing temperature of 80 ℃ for 2h, and then cutting the composite sleeve into a rubber sleeve with the length of 30mm by using a coil pipe machine or a cutting, placing the flexible sleeve into a dipping tank filled with nickel-coated aluminum powder, wherein the dipping time is 40min, so that the exposed parts at the two ends of the flexible sleeve are also coated with conductive fillers to obtain the flexible sleeve with the inside being rubber and the surface being fully coated with the conductive fillers, and thus the flexible sleeve for electromagnetic shielding is prepared.
The nickel-coated aluminum powder dipping solution is filled, the deionized water part/nickel-coated aluminum powder part is 0.6, the addition part of the hexanediol is 0.4 of the deionized water part, and the addition part of the toluene is 0.2 of the deionized water part.
Specifically, in the above embodiment of the present invention, the conductive particles are modified by one or more surfactants selected from silane coupling agents, titanate coupling agents, and aluminate coupling agents.
Specifically, in the above specific embodiment of the present invention, in the preparation process by a co-extrusion method, the conductive particles and the silicone oil are uniformly blended and then used, and the feeding mass ratio of the conductive particles to the silicone oil is 50-90: 10 to 50; after extrusion, the silicone oil volatilizes and the conductive particles form a conductive coating.
Specifically, in the above specific embodiment of the present invention, the conductive coating formed by the conductive particles is in the micron order.
The invention is described in further detail below with reference to the accompanying drawings:
referring to fig. 1 and 2, which are schematic radial and axial cross-sectional views of a flexible bushing for electromagnetic shielding according to the present invention, it can be seen that a rubber tube is disposed in the middle as a base body 2, a conductive coating 1 is coated on both the inner surface of the rubber tube and the outer surface of the rubber tube, and an inner hole structure is disposed in the middle of the flexible bushing for electromagnetic shielding.
Referring to Table 1, tensile strength (ASTM D412), elongation at break (ASTM D412), compression set (ASTM D395) and shielding effectiveness values (MiL-DLT-83528 and MiL-SDT-285: 200 KHz-10 GHz) of the flexible sleeves for electromagnetic shielding prepared for the above-described examples 1 to 15 of the present invention.
Table 1 performance test table for electromagnetic shield prepared in the above-mentioned examples 1 to 15
The above-mentioned contents are only for illustrating the technical idea of the present invention, and the protection scope of the present invention is not limited thereby, and any modification made on the basis of the technical idea of the present invention falls within the protection scope of the claims of the present invention.
Claims (10)
1. A method of making a flexible bushing for electromagnetic shielding, comprising: preparing a rubber tube by mixing and vulcanizing rubber and an auxiliary agent, and coating a conductive coating on the inner surface of the obtained rubber tube, the outer surface of the rubber tube and the end surface of the rubber tube to prepare a flexible sleeve for electromagnetic shielding;
wherein the conductive coating comprises conductive particles.
2. The method for preparing a flexible bushing for electromagnetic shielding according to claim 1, wherein the conductive particles comprise one or more of silver powder, nickel powder, copper powder, silver-coated aluminum powder, silver-coated copper powder, silver-coated glass beads, nickel-coated aluminum powder, and nickel-coated graphite powder.
3. The method for preparing a flexible bushing for electromagnetic shielding according to claim 2, wherein the silver content in the silver-coated aluminum powder, the silver-coated copper powder, the silver-coated glass beads, the nickel-coated aluminum powder or the nickel-coated graphite powder is 10% to 60%, and the nickel content is 60% to 80%.
4. The method of claim 1, wherein the conductive particles have a particle size of 0.01 to 50 μm.
5. The method of claim 1, wherein the rubber comprises silicone rubber, fluorosilicone rubber, or ethylene propylene rubber.
6. The method for preparing a flexible bushing for electromagnetic shielding according to claim 1, wherein the flexible bushing is prepared by a spraying method, and comprises the following steps:
1) extruding and molding the rubber dispersed with the auxiliary agent to obtain a rubber tube; spraying conductive particles on the inner surface of the rubber tube by using an inner spray gun to form an inner coating, and spraying conductive particles on the outer surface of the rubber tube by using an outer spray gun to form an outer coating to prepare a coated rubber tube by using an electrostatic plastic spraying technology;
2) the obtained rubber tube with the surface fully coated with the conductive coating is baked, leveled and cured at high temperature to obtain an inner surface and outer surface coated rubber tube;
3) and spraying conductive particles on the end faces of the obtained inner and outer surface-coated rubber tubes by using an outer spray gun to form the rubber tubes with the surfaces fully coated with the conductive coatings, namely manufacturing the flexible sleeve for electromagnetic shielding.
7. The method for preparing a flexible sleeve for electromagnetic shielding according to claim 6, wherein the electrostatic plastic spraying technology is adopted, and the working parameters thereof comprise:
the electrostatic high voltage is 60-90 kV, the electrostatic current is 10-20 muA, the flow velocity pressure is 0.30-0.55 MPa, the atomization pressure is 0.30-0.45 MPa, the gun cleaning pressure is 0.4-0.5 MPa, the fluidization pressure of a powder supply barrel is 0.04-0.10 MPa, and the powder output is 500-600 g/min.
8. The method for preparing a flexible sleeve for electromagnetic shielding according to claim 1, wherein the flexible sleeve is prepared by a full immersion method, and the method comprises the following steps:
extruding and molding the rubber dispersed with the auxiliary agent to obtain a rubber tube; and (3) dipping the obtained rubber tube in a conductive particle dipping solution, and then curing to form the rubber tube with the surface fully coated with the conductive coating, namely the flexible sleeve for electromagnetic shielding is prepared.
9. The method for preparing a flexible bushing for electromagnetic shielding according to claim 1, wherein the flexible bushing is prepared by co-extrusion, which comprises the following steps:
1) respectively filling the conductive slurry into two extruders by a co-extrusion technology, filling the rubber dispersed with the auxiliary agent into one extruder, extruding and molding the three extruders through a co-extrusion die, fusing and adhering the conductive coating with the inner surface of the rubber tube and the outer surface of the rubber tube at the same time in the co-extrusion die to prepare a composite sleeve, and carrying out high-temperature sizing sleeve on the obtained composite sleeve to prepare the rubber sleeve with the inner surface and the outer surface coated with the conductive coating;
2) and placing the obtained rubber sleeve with the inner surface and the outer surface coated with the conductive coating in conductive particle immersion liquid, coating the exposed structures at two ends to form a rubber tube with the surface fully coated with the conductive coating, and curing to obtain the flexible sleeve for electromagnetic shielding.
10. A flexible bushing for electromagnetic shielding manufactured by the manufacturing method of any one of claims 1 to 9.
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Citations (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN102329560A (en) * | 2010-07-14 | 2012-01-25 | 中化化工科学技术研究总院 | Novel electromagnetic shielding paint for surface of silicone rubber |
| CN109102962A (en) * | 2018-07-03 | 2018-12-28 | 北京中科纳通电子技术有限公司 | The Preparation method and use of conductive rubber strip |
| US20200105437A1 (en) * | 2017-11-20 | 2020-04-02 | South China University Of Technology | Superhydrophobic conductive coating and method for preparing the same |
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- 2021-02-07 CN CN202110177603.9A patent/CN112961389A/en active Pending
Patent Citations (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN102329560A (en) * | 2010-07-14 | 2012-01-25 | 中化化工科学技术研究总院 | Novel electromagnetic shielding paint for surface of silicone rubber |
| US20200105437A1 (en) * | 2017-11-20 | 2020-04-02 | South China University Of Technology | Superhydrophobic conductive coating and method for preparing the same |
| CN109102962A (en) * | 2018-07-03 | 2018-12-28 | 北京中科纳通电子技术有限公司 | The Preparation method and use of conductive rubber strip |
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Application publication date: 20210615 |