KR101579522B1 - Resin composition having electro-magnetic wave absorption function with high thermal radiation, and molded article manufacture by using the same - Google Patents

Abstract

The present invention provides a resin composition which is useful for producing a lightweight motor case or a tray for organizing wires, due to having excellent heat-radiating properties and electromagnetic shielding and absorbing capabilities. The present invention further provides a molded body produced by using the same.

Description

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a resin composition having excellent heat dissipation properties, electromagnetic wave shielding and absorption ability, and molded articles produced using the same. BACKGROUND ART [0002]

The present invention relates to a resin composition having electromagnetic wave shielding and absorption ability together with an excellent heat radiation property and a molded article produced using the same.

Generally, automobile parts and cases of electronic products are made of metal plates in a desired shape through a press. However, the metal material has a heavy weight and a complicated manufacturing process. For example, aluminum has an excellent thermal conductivity of 200 W / mK or more and electromagnetic shielding performance, making it an ideal material for application to heat-generating motor cases. Generally, the aluminum case is manufactured by a die casting method, and the defect rate is high, a post-processing step is required, and the weight of the aluminum molded body is heavy compared with the plastic.

In order to solve such a problem, a method using a resin composition of high rigidity or impact resistance has been proposed. However, the resin composition has a problem of low electromagnetic wave shielding function and rigidity.

In recent years, a method of manufacturing a shell plate or the like of a vehicle using a fiber reinforced plastic material has been used. However, such a fiber reinforced plastic material has a problem in that productivity is low due to complicated manufacturing process.

Therefore, it is required to develop a resin composition which is useful for manufacturing a motor case that simultaneously satisfies lightweight problems in various motors, heat radiation, and electromagnetic wave problems.

Korean Patent Publication No. 2004-0029073 (published on April 03, 2004) Korean Published Patent Application No. 2007-0120104 (published on December 21, 2007)

An object of the present invention is to provide a resin composition having electromagnetic wave shielding and absorption ability together with an excellent heat radiation property.

It is still another object of the present invention to provide a molded article which is manufactured using the above resin composition and which has excellent heat radiation characteristics, electromagnetic wave shielding and absorption ability, and is light in weight.

According to an embodiment of the present invention, there is provided a method of manufacturing a semiconductor device, which comprises 5 to 30% by weight of a semi-graphene, 10 to 35% by weight of a carbon fiber, and 20 to 60% Wherein the polymeric material is selected from the group consisting of polycarbonate, poly (phenylene sulfide), poly (butylene terephthalate), polyamide, polypropylene but are not limited to, polypropylene, polyethylene, poly (methyl methacrylate), ethylene vinyl acetate, poly vinyl butyral, polyether ketone ), And a mixture thereof.

In the resin composition, the semi-graphene is obtained by spinning the expanded graphite at a high speed of 1,000 to 1,100 rpm for 45 to 50 seconds under an inert gas atmosphere and then rotating at 600 to 800 rpm for 10 to 15 seconds at low speed, And may be manufactured by performing a ball milling process 10 times.

The semi-graphene may have an average particle diameter of 100 nm to 10 mu m.

In addition, the carbon fibers may have an aspect ratio (length / diameter ratio) of 10 to 400.

In addition, the carbon fibers may be included in the resin composition to form a three-dimensional network structure.

The resin composition may further include at least one of carbon nanotube and graphite in an amount of 0.1 to 10% by weight based on the total weight of the resin composition.

The carbon nanotubes may be selected from the group consisting of single-walled carbon nanotubes, double-walled carbon nanotubes, multi-walled carbon nanotubes, multi-walled carbon nanotubes, and mixtures thereof.

The resin composition may further comprise an additive selected from the group consisting of a silane compound, a dispersant, a metal or metal oxide powder, an alloy powder, a ferrite powder, a filler, a crosslinking accelerator, a curing agent, a wax and a mixture thereof .

According to another embodiment of the present invention, there is provided a kneaded product obtained by mixing 5 to 30% by weight of semi-graphene, 10 to 35% by weight of carbon fibers and 20 to 60% by weight of a polymer material in a solvent, (Phenylene Sulfide), poly (butylene terephthalate), polyamide, polypropylene < RTI ID = 0.0 > , Polyethylene, poly (methyl methacrylate), ethylene vinyl acetate, polyvinyl butyral, polyether ketone, and mixtures thereof.

According to another embodiment of the present invention, there is provided a method of manufacturing a semiconductor device, comprising: preparing a first pellet by mixing semi-graphene and a polymer material in a solvent, followed by kneading, drying, and compounding; Mixing a carbonaceous material including a carbon fiber and a polymer material in a solvent, kneading, drying and compounding to produce a second pellet; And mixing the first pellet and the second pellet in a weight ratio of 90:10 to 10:90, wherein the polymer material is selected from the group consisting of polycarbonate, poly (phenylene sulfide), poly (butylene terephthalate) Wherein the thermoplastic resin is selected from the group consisting of polyamide, polyamide, polypropylene, polyethylene, poly (methyl methacrylate), ethylene vinyl acetate, polyvinyl butyral, polyether ketone, , The graphite and the polymeric material are used in an amount such that the graphite and the polymeric material are contained in an amount of 5 to 30% by weight of the semi-graphene, 10 to 35% by weight of the carbon fiber, and 20 to 50% A method of making a composition is provided.

According to still another embodiment of the present invention, there is provided a molded article formed by injection molding the above-mentioned resin composition.

The molded article may have a thermal conductivity of 3 W / mK or more and an electromagnetic wave shielding ratio of -100 to -10 dB.

The molded body may be a motor case or a tray for arranging wiring.

Other details of the embodiments of the present invention are included in the following detailed description.

The thermoplastic resin composition according to the present invention has excellent heat dissipation properties and electromagnetic wave shielding and absorption ability and is suitable for a lightweight motor case, especially a case of a DC motor or a BLDC motor (Brush less Direct Current Motor) It is useful for manufacturing trays for wiring, tray for aircraft wiring, and trays for car wiring.

Fig. 1 is a view showing the specifications of a specimen used in the electromagnetic wave shielding test.
Fig. 2 is a photograph of a sample of the sample used in the electromagnetic wave shielding test.

The present invention is capable of various modifications and various embodiments and is intended to illustrate and describe the specific embodiments in detail. It is to be understood, however, that the invention is not to be limited to the specific embodiments, but includes all modifications, equivalents, and alternatives falling within the spirit and scope of the invention.

As used herein, the term "shaped body" is a highly rigid material having both heat dissipation and electromagnetic wave absorption functions and includes various processing (or molding) forms such as pellet, film or sheet do.

According to an embodiment of the present invention, there is provided a method for producing a polymeric material, comprising: (a) 5 to 30% by weight of a semi-graphene; (b) 10 to 35% by weight of carbon fibers; and (c) % ≪ / RTI >

Each component will be described in detail below.

(a) Semi grains

The semi-graphene is produced by mechanical particle separation of expanded graphite by controlling the rotation period of the ball mill apparatus, and exhibits electric and thermal characteristics 1.5 to 3 times higher than that of expanded graphite.

Specifically, the semi-graphene is produced by charging expandable graphite into a ball mill and then rotating it at a high speed of 1,000 to 1,100 rpm for 45 to 50 seconds under an inert gas atmosphere and then at low speed for 10 to 15 seconds at 600 to 800 rpm. Cycle, and performing a ball milling process 5 to 10 times.

Specifically, natural graphite is subjected to pulverization water-dispersing process to produce 95% or more of graphite, and a strong acid washing step and a high temperature and high- A sintering step in an alkali state is carried out in sequence, a chemical is inserted between layers in the graphite through a chemical treatment, and a subsequent neutralization, cleaning and drying step is carried out. At this time, it may be preferable to increase the purity to 99.5% or more through an additional cleaning process after the sintering process.

The ball mill apparatus used in the production of the semi-graphene is a device for crushing or separating an object by the impact force of a ball having a plurality of balls in the chamber. The ball mill apparatus includes various ball mill apparatuses . ≪ / RTI >

In the case of a ball mill apparatus without an impeller, a rotating chamber wall collides with a free falling ball, and the object is crushed and separated by an impact force generated between the ball and the chamber wall. Also, in a ball mill apparatus having an impeller, ball vibrating due to rotation of the impeller collides with each other, and the object is crushed and separated by a very strong impact force generated between the ball and the ball. In the case of a planetary ball mill system composed of a large chamber and two small chambers inside, the pulverization and separation are effected by the mechanical energy of the ball without impeller. In this case, the outer large chamber and the small inner chamber By rotating in opposite directions, the mechanical energy can be further increased. Accordingly, it is more preferable to perform the mechanical and physical particle separation of the semi-graphene powder using the planetary ball mill.

Also, it may be preferable to perform the ball milling process at 5 to 10 times in one cycle, which is a high-speed rotation at 1,000 to 1,100 rpm for 45 to 50 seconds and then a low-speed rotation at 600 to 800 rpm for 10 to 15 seconds. By alternately performing the high-speed rotation and the low-speed rotation in this way, overheating of the chambers in the planetary ball-mill and thus the overheating of the semigravain can be prevented.

In addition, if the high-speed rotation process is performed for less than 45 seconds, the separation of the expanded graphite is not sufficient, and if it is carried out for more than 50 seconds, the friction of the balls introduced into the chamber causes contaminants such as metal fragments and ball fragments Which may cause secondary contamination of the semi-graphene.

In addition, when the high-speed rotation speed is more than 1,000 rpm and less than 1,100 rpm, the separation of the expanded graphite in the chamber is deteriorated and there is a fear of secondary contamination due to friction of the balls put into the chamber.

If the cycle is carried out less than 5 times, the particles of the expanded graphite are not sufficiently separated, and if the cycle is carried out more than 10 times, frictional heat may excessively occur in the expanded graphite.

It is also preferable that the semi-graphene is produced in an inert gas atmosphere such as argon or nitrogen. If semi-graphene is produced in air, the reactivity between expanded graphite increases, and static electricity is generated by charging, which may result in agglomeration of expanded graphite. Further, when the reaction is carried out in an inert gas atmosphere, the reactivity, particularly the oxidation reaction, is lowered, so that the generation of static electricity can be prevented and the mechanical particle separation of the expanded graphite can be promoted.

The semi-graphene preferably has an average particle diameter of 100 nm to 10 mu m. When the average particle diameter of the semi-graphene is less than 100 nm, the electrical and thermal properties of the resin composition are not sufficiently improved due to the aggregation between the semi-graphene grains. If the average particle diameter is more than 10 탆, There is a possibility that the workability of the substrate is deteriorated.

The semi-graphene may be contained in an amount of 5 to 30% by weight based on the total weight of the resin composition. If the content of the semi-graphene is less than 5% by weight, the improvement effect due to the addition of the semi-graphene is insignificant. If the content exceeds 30% by weight, the rigidity of the resin composition may be deteriorated. Considering the remarkable improvement effect of the addition of the semi-graphene, it is preferable that the semi-graphene is contained in an amount of 15 to 30% by weight based on the total weight of the resin composition.

(b) carbon fiber

The carbon fibers have an excellent electrical conductivity and serve to improve the electromagnetic wave absorbing ability of the resin composition. The carbon fibers may be coated with a metal if necessary.

The carbon fibers have an aspect ratio (ratio of length / diameter) of 10 to 400, or 40 to 100 because the formation of a three-dimensional network by the contact between the carbon fibers in the resin composition can improve the electrical conductivity and the electromagnetic wave absorbing ability . However, if the aspect ratio of the carbon fibers is less than 10, the network formation is difficult and the effect of improving the electromagnetic wave absorbing ability is insignificant. If the aspect ratio exceeds 400, the rigidity of the resin composition may be deteriorated.

Such a carbon fiber may be contained in an amount of 1 to 35% by weight based on the total weight of the thermoplastic resin composition. When the carbon fiber of the carbon fiber is less than 1% by weight, the effect of improving the electromagnetic wave absorbability by the use of the carbon fiber is insignificant, and when it exceeds 35% by weight, the rigidity may be lowered. Considering the remarkable improvement effect of use of the carbon fibers, it is preferable that the carbon fibers are included in an amount of 10 to 20% by weight based on the total weight of the resin composition.

(c) Polymer material

The polymer material may be a polymer that can be used in an injection molding process. Examples of the polymer include polycarbonate (PC), poly (phenylene sulfide), PPS, poly (butylene terephthalate) butylene terephthalate (PBT), polyamide (specifically PA6, PA66 (homopolyamide based on hexamethylenediamine and adipic acid), polypropylene (PP), polyethylene (PE) Polyvinyl butyral (PVB), polyether ketone (PEK), and the like can be used as the binder resin , And one of these may be used alone, or a mixture of two or more thereof may be used.

It may be preferable that the polymer material is pulverized before use to be undifferentiated.

The polymer material may be contained in an amount of 20 to 60% by weight or 40 to 60% by weight based on the total weight of the resin composition. If the content of the polymer material is less than 20% by weight, the amount of the polymer material to be used may be too small to reduce the moldability and mechanical properties of the resin composition. If the content exceeds 60% by weight, There is a risk of degradation.

The resin composition having the above-described composition may further contain at least one of carbon nanotube and graphite in an amount of 0.1 to 10% by weight based on the total weight of the resin composition, together with the above-mentioned components.

The carbon nanotube has excellent electrical conductivity, thermal conductivity, and rigidity, so that heat radiation and electromagnetic wave absorption performance of the resin composition can be improved.

Specifically, the carbon nanotube may be a single-walled carbon nanotube (SWCNT), a double-walled carbon nanotube (DWCNT), a multi-walled carbon nanotube (MWCNT) ) Or a rope carbon nanotube, and either one of them or a mixture of two or more of them may be used.

In addition, in terms of electrical conductivity, multi-walled carbon nanotubes and multi-walled carbon nanotubes are excellent, and in terms of thermal conductivity, single-walled carbon nanotubes exhibit superior effects. Accordingly, it is more preferable to mix the single-walled carbon nanotubes with the multi-walled or bundle-type carbon nanotubes in consideration of heat dissipation and electromagnetic wave absorption performance required in the application field of the resin composition.

The carbon nanotubes may be contained in an amount of 0.1 to 10% by weight based on the total weight of the resin composition, but may be more preferably 0.1 to 3% by weight. When the content of the carbon nanotubes is less than 0.1% by weight, the improvement effect of the use of the carbon nanotubes is insignificant. When the content is more than 3% by weight, the rigidity of the resin composition may be deteriorated. Considering the remarkable improvement effect of use of the carbon nanotubes, it is more preferable that the carbon nanotubes are contained in an amount of 1 to 3 wt% based on the total weight of the resin composition.

The graphite serves to improve the mechanical properties such as the tensile strength of the resin composition. Specifically, the graphite may be impregnated graphite or highly crystalline graphite, and impregnated graphite is preferable, and granular impression graphite having a size of 20 to 80 mesh may be more preferable. When the graphite has a size within the above-mentioned range, the improvement in the mechanical properties or the reinforcing performance for the resin composition is significant. If the particle size is less than 20 mesh, the aggregation of the graphite particles may be unevenly dispersed in the resin composition. As a result, the mechanical properties of the resin composition may deteriorate. When the particle size of the graphite exceeds 80 mesh, the mixing property with the resin composition is lowered and the homogeneous mixing is difficult, and the mechanical properties of the resin composition may be deteriorated.

The above-mentioned graphite may be contained in an amount of 0.1 to 10% by weight, or 1 to 10% by weight based on the total weight of the resin composition. When the amount of graphite added is less than 0.1 wt%, the improvement effect of graphite is small. When the amount of graphite is more than 10 wt%, the elongation percentage of the resin composition may decrease. Considering the remarkable improvement effect of the use of graphite, it is preferable that the graphite is contained in an amount of 1 to 5% by weight based on the total weight of the resin composition.

The resin composition may further comprise a silane-based compound.

When the resin composition is cured due to steric hindrance of the long chain type functional group, the silane compound can increase the heat radiation effect of the resin composition by forming open pores having a diameter of not more than micron. Specific examples of the silane compound include 3-glycidyloxypropyltrimethoxysilane, 3-glycidyloxypropyltriethoxysilane, 3-glycidyloxypropylmethylmethoxysilane, 3-glycidyloxy 3-methacryloxypropyltrimethoxysilane, 3-glycidoxypropylmethyldimethoxysilane, heptadecafluorodecyl silane, heptadecafluorodecyl silane, heptadecafluorodecyl silane, heptadecafluorodecyl silane, Methacryloxypropyltrimethoxysilane, methoxysilane, 3-methacryloxypropylmethyldimethoxysilane, 3-methacryloxypropyltris (trimethylsiloxy) silane, methyltris (dimethylsiloxy) 3-mercaptopropyltrimethoxysilane, N- (? -Aminoethyl) -? - aminopropyltrimethoxysilane, 3- [N-anil- ] Aminopropyltrimethoxysilane, 3- (N-anil-N-glycidyl) aminopropyltri N, N-bis [3- (trimethoxycinnamyl) propyl] methacrylamide and [gamma] -glycidoxime Trimethyldimethoxysilane, and trimethyldimethoxysilane.

The silane compound may be contained in an amount of 0.5 to 5% by weight based on the total weight of the resin composition. If the content of the silane-based compound is less than 0.5 wt%, the effect of using the silane-based compound is insignificant. If the content of the silane-based compound exceeds 5 wt%, the mechanical properties of the resin composition may deteriorate due to excessive open pore formation.

The resin composition according to the present invention may further comprise a dispersant.

The dispersant serves to increase the dispersibility of particulate matter such as carbon nanotubes and carbon fibers in the resin composition. Specifically, the dispersant may be a urethane, acrylic, phosphorus, organic acid salt, inorganic acid salt, Can be used.

The dispersant may be contained in an amount of 0.5 to 7% by weight based on the total weight of the resin composition. If the content of the dispersant is less than 0.5% by weight, the effect of using the dispersant is insignificant. If the content of the dispersant is more than 7% by weight, there is no synergistic effect due to the excessive content.

The resin composition may further include at least one additive selected from electroconductive additives, fillers, crosslinking accelerators, hardeners, and waxes in addition to the above-mentioned components.

Specifically, metal powder, alloy powder, or ferrite powder may be used as the electrically conductive additive. More specifically, the metal powder may be at least one selected from the group consisting of Ag, Au, Pt, Cu, Ni, Pd, Co, Rh, Metal oxide such as tin oxide, indium oxide, indium tin oxide (ITO), antimony oxide, zinc antimony oxide or antimony tin oxide may be used as the metal fine particles such as tin (Ru) or tin (Sn) As the alloy powder, a powder of a sendust series, a permalloy series, a molypermalloy series, and an amorphous series may be used. As the ferrite powder, iron oxide (Fe ₂ O ₃ ), nickel oxide (NiO), zinc oxide (ZnO), copper oxide (CuO), nickel-zinc ferrite or manganese-zinc ferrite powder may be used.

Specific examples of the filler include silica, silicon carbide, magnesium oxide, zirconia, alumina and titania. One of these fillers may be used alone or a mixture of two or more thereof may be used. Can be used.

The resin composition having the above-mentioned composition is obtained by mixing 5 to 30% by weight of semi-graphene, 10 to 35% by weight of carbon fibers and 20 to 60% by weight of a polymer material in a solvent, kneading and drying, (Step 1), and preparing a pellet by compounding the dried kneaded product (step 2).

In step 1 of the above-mentioned dried kneaded product, the kinds and amounts of the semigravidin, the carbon fiber and the polymer material usable in the production of the resin composition are the same as those described above. At this time, at least one of carbon nanotube and graphite may be added in an amount of 0.1 to 10% by weight based on the total weight of the resin composition, and a silane compound, dispersant, metal or metal oxide powder, alloy powder, ferrite powder, , A crosslinking accelerator, a curing agent, a wax, and a mixture thereof may be further mixed.

Examples of the solvent include alcohols such as methyl alcohol, ethyl alcohol, isopropyl alcohol and butanol, and single solvents selected from benzene, xylene, texanol, ethylene glycol, butyl carbitol, ethyl cellosolve, glycerol, Or a mixture of two or more of them may be used. Further, an aqueous solvent such as water may be used instead of the organic solvent.

In addition, it may be preferable to previously dissolve the dispersant for uniform dispersion and kneading of the above-mentioned components in a solvent before the semi-graphene, the carbon fiber and the polymer material are added to and mixed with the solvent. By dissolving the dispersant in the solvent in this way, the dispersibility of the components to be added subsequently can be improved, and the bonding force between the components during the injection molding of the resin composition can be improved.

Further, after the mixing of the semi-graphene, the carbon fiber and the polymer material and the solvent, an optional dispersion process may be further performed to improve the dispersion uniformity of the respective components in the mixture. The dispersion process may be carried out using a continuous ultrasonic device or a batch type device.

After completion of the mixing and optional dispersion process, a kneading process according to an ordinary method may be performed.

After completion of the kneading step, a drying step may be performed, and the drying step may be performed according to a conventional drying method such as hot air drying, heat drying, and the like.

The dried kneaded product obtained as a result of the above-mentioned drying step is subjected to a pellet preparation step through a compounding process.

The compounding step may be carried out using a conventional compounding equipment. Specifically, a twin screw extruder or a co-kneader may be used.

Alternatively, the resin composition may be prepared by mixing a semi-graphene and a polymer material in a solvent, and then kneading, drying, and compounding to produce a first pellet; Mixing a carbonaceous material including a carbon fiber and a polymer material in a solvent, kneading, drying and compounding to produce a second pellet; And mixing the first pellet and the second pellet in a weight ratio of 90:10 to 10:90.

The semi-graphene, the carbon fiber and the polymer material are the same as described above, and the respective contents can be used in an amount to satisfy the content condition of each constituent component in the resin composition. When the resin composition further comprises graphite or carbon nanotubes, it is more preferable that graphite is added at the time of preparing the first pellet and the carbon nanotubes are respectively added at the time of producing the second pellet, considering the mixing uniformity and the like .

The kneading, drying and compounding processes for producing the first and second pellets may be carried out in the same manner as described above.

When the first and second pellets are separately prepared as described above, uniform mixing is possible and the extrusion can be performed.

The prepared first and second pellets may be mixed at a weight ratio of 90:10 to 10:90, and the mixing process may be performed at 30 to 60 rpm for 10 to 60 minutes using a kneader.

The resin composition produced by the above production method can be a carbon-based material reinforced plastic exhibiting high rigidity and having excellent heat radiation and electromagnetic wave absorption ability. More specifically, the resin composition may be a resin composition for a motor case that requires high rigidity, heat radiation, and electromagnetic wave absorbing ability.

Accordingly, the resin composition produced in the form of pellets can be molded into a lightweight molded article having an excellent heat dissipation property as well as an electromagnetic wave absorbing function as well as a high rigidity property compared with a conventional metal material through an injection process. Specifically, the molded article has a tensile strength of 80 to 200 MPa, an elongation of 1 to 3%, and a flexural strength of 100 to 300 MPa. The molded article may have a thermal conductivity of 3 W / mK or more, or 3 W / mK to 6 W / mK, and an electromagnetic wave shielding ratio of -100 to -10 dB.

Specifically, the molded body may be a case (housing) of various electronic devices or vehicle parts such as a tray for ship wiring, a tray for arranging aircraft wiring, a tray for car wiring, a diocase, a set- (For example, a DC and BLDC motor case or the like) or a tray for arranging wiring, in which electromagnetic wave shielding and absorption ability and light weight are required, together with excellent heat radiation characteristics.

Hereinafter, the present invention will be described in more detail with reference to specific examples. However, the following examples are merely illustrative of the present invention, and the contents of the present invention are not limited by the following examples.

Example

Each of the components described in Table 1 below was dry mixed with a base content, mixed in ethylene glycol as a solvent, kneaded and dried. The dried kneaded product was compounded to prepare a resin composition in the form of a pellet.

Polymer materials ¹⁾ Carbon fiber ²⁾ Semi graphene ³⁾ Carbon nanotubes ⁴⁾ Example 1 60 30 10 0 Example 2 50 30 20 0 Example 3 40 30 30 0 Example 4 40 30 25 5 Example 5 59 20 20 One Example 6 57 20 20 3 Example 7 55 20 20 5

In Table 1, the content unit of each component is% by weight

(1) Polymer material: polyamide (PA6)

(2) Carbon fiber: Carbon fiber having an aspect ratio of 50

(3) Semi-graphene: Semi-graphene: Expanded graphite is rotated at a high speed of 1,000 to 1,100 rpm for 45 to 50 seconds under an inert gas atmosphere and then rotated at 600 to 800 rpm for 10 to 15 seconds at low speed. And had an average particle diameter of 400 nm.

(4) Carbon nanotubes: Multi-walled carbon nanotubes

Test Example

Tensile strength, elongation, flexural strength, impact strength, thermal conductivity, and electromagnetic shielding ratio of the prepared specimens were measured in the following manner.

Tensile strength and elongation at break were measured according to ASTM D638-10, and flexural strength was measured according to ASTM D790-10 (procedure A).

The thermal conductivity was measured using a thermal conductivity analyzer (TCI name of C-Term company, thermal conductivity range 0 to 100 W / mk, measurement time 0.08 second to 5 seconds).

The electromagnetic wave shielding test was carried out according to the ASTM D4935-10 method using the apparatus shown in Table 2 below, and specimens used for the test were as shown in Figs. 1 and 2.

Equipment name model name Specifications manufacturer Test receiver ESCI 9kHz - 3.0GHz Rohde & Schwarz Far field test fixture EM-2107A 30MHz - 1.5GHz Electro Metrics Attenuator 34-10-34 DC-18GHz 10dB, 2EA Aeroflex / Weinschel Rf amplifier 10WD1000, 5S1G4 DC-1000MHz 40dB, 800MHz 4.2GHz 38dB Amplifier Research

The results are shown in Table 3 below.

The tensile strength
(MPa) Elongation
(%) Flexural strength
(MPa) Thermal conductivity
(W / mK) Electromagnetic wave shielding rate
(dB) Example 1 166 2.5 203 5.8 -18 Example 2 116 1.7 163 5.4 -19 Example 3 84 1.0 139 6.1 -22 Example 4 120 1.8 160 3.9 -42 Example 5 120 1.8 160 3.8 -38 Example 6 86 1.6 156 3.9 -52 Example 7 82 1.4 153 3.9 -55

The results of the tests of Table 3 show that the specimens of the resin compositions of Examples 1 to 7 according to the present invention exhibit excellent thermal conductivity and electromagnetic shielding ratio together with excellent mechanical properties and exhibit improved heat radiation effect and electromagnetic wave absorption performance .

It will be apparent to those skilled in the art that various modifications and variations can be made in the present invention without departing from the spirit of the invention as set forth in the appended claims. The present invention can be variously modified and changed by those skilled in the art, and it is also within the scope of the present invention.

Claims (13)

5 to 30% by weight of a semi-graphene,
10 to 35% by weight of carbon fiber, and
20 to 60% by weight of a polymeric material,
The polymeric material may be selected from the group consisting of polycarbonate, poly (phenylene sulfide), poly (butylene terephthalate), polyamide, polypropylene, Polypropylene, polyethylene, poly (methyl methacrylate), ethylene vinyl acetate, poly vinyl butyral, polyether ketone, and the like. ≪ / RTI > and mixtures thereof,
Wherein the carbon fibers have an aspect ratio (ratio of length / diameter) of 10 to 400. The method according to claim 1,
The semi-graphene is subjected to a ball milling process 5 to 10 times by rotating the expanded graphite at a high speed of 1,000 to 1,100 rpm for 45 to 50 seconds under an inert gas atmosphere and then at low speed for 10 to 15 seconds at 600 to 800 rpm By weight. The method according to claim 1,
Wherein the semi-graphene has an average particle diameter of 100 nm to 10 mu m. delete The method according to claim 1,
Wherein the carbon fibers are contained in the resin composition to form a three-dimensional network. The method according to claim 1,
Carbon nanotubes and graphite in an amount of 0.1 to 10% by weight based on the total weight of the resin composition. The method according to claim 6,
Wherein the carbon nanotubes are selected from the group consisting of single-walled carbon nanotubes, double-walled carbon nanotubes, multi-walled carbon nanotubes, multi-walled carbon nanotubes, and mixtures thereof.
The method according to claim 1,
Wherein the resin composition further comprises an additive selected from the group consisting of a silane compound, a dispersant, a metal or metal oxide powder, an alloy powder, a ferrite powder, a filler, a crosslinking accelerator, a curing agent, a wax and a mixture thereof. Mixing 5 to 30% by weight of semi-graphene, 10 to 35% by weight of carbon fiber, and 20 to 60% by weight of a polymer material in a solvent, kneading and drying to prepare a dried kneaded product, and
And compounding the dried kneaded product to prepare a pellet,
Wherein the polymeric material is selected from the group consisting of polycarbonate, poly (phenylene sulfide), poly (butylene terephthalate), polyamide, polypropylene, polyethylene, poly (methyl methacrylate), ethylene vinyl acetate, polyvinyl butyral, And mixtures thereof. ≪ / RTI > Mixing the semi-graphene and the polymer material in a solvent, and then kneading, drying, and compounding to produce a first pellet;
Mixing a carbonaceous material including a carbon fiber and a polymer material in a solvent, kneading, drying and compounding to produce a second pellet; And,
Mixing the first pellet and the second pellet in a weight ratio of 90:10 to 10:90,
Wherein the polymeric material is selected from the group consisting of polycarbonate, poly (phenylene sulfide), poly (butylene terephthalate), polyamide, polypropylene, polyethylene, poly (methyl methacrylate), ethylene vinyl acetate, polyvinyl butyral, ≪ / RTI > and mixtures thereof,
Wherein the semi-graphene, carbon fiber and polymeric material are contained in an amount of 5 to 30% by weight of the semi-graphene, 10 to 35% by weight of the carbon fiber and 20 to 60% by weight of the polymeric material, By weight based on the total weight of the resin composition. A molded article formed by injection molding the resin composition according to claim 1. 12. The method of claim 11,
A thermal conductivity of 3 W / mK or more, and an electromagnetic wave shielding ratio of -100 to -10 dB. 12. The method of claim 11,
Molded body that is a motor case or tray for wiring arrangement.

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