KR101655419B1 - High thermally conductive electrically insulative alumina composition and polymer shaped article manufactured by using them, a process for preparation thereof - Google Patents

Abstract

The present invention relates to a highly heat conductive electrically insulating composition, to a polymer molded article manufactured therefrom, and to a manufacturing method of the composition and the polymer molded article. The highly heat conductive electrically insulating composition has enhanced heat conductivity and electrical insulation by filling pores of alumina with carbon nanotubes (CNT). More particularly, the highly heat conductive electrically insulating composition comprises: 93-97.5 wt% of alumina; and 2.5-7 wt% of CNT impregnated inside pores of the alumina.

Description

TECHNICAL FIELD [0001] The present invention relates to a high-temperature conductive electrically insulating composition, a polymer molding made therefrom, and a method of manufacturing the same. BACKGROUND ART [0002]

TECHNICAL FIELD The present invention relates to a high thermal conductive electric insulating composition having excellent thermal conductivity and electrical insulating properties, a polymer molding produced from the composition, and a method of manufacturing the same.

Various heating elements such as various mechanical devices and electric appliances can not effectively dissipate the excessive heat generated from the inside of the device to the outside, which threatens the performance of the product or the stability of the operation of the device, and causes severe problems such as explosion and fire do.

The technology of effectively releasing the heat of the heating element to the outside or cooling it is important. Conventionally, various methods such as installing a heat sink or a heat dissipating fan to control such heat have been attempted. However, in the case of a heat sink, the amount of heat that can be discharged from the heat sink to the outside is lower than the amount of heat generated from the heat emitting body. Therefore, a heat-radiating fan is additionally installed in the heat sink to bypass the heat generated by the heat-generating body.

The heat radiating fan causes noise and vibration of the apparatus, requires a separate power source, and is required to be lightweight and slim, and has a problem in that it is limited in its utilization.

Although metal occupies a large portion as a main material of a heat sink as a heat dissipating means, there is an increasing tendency to substitute metal for reasons of low moldability and productivity of the metal. The development of high thermal conductivity materials using polymers is also an alternative to metal substitution, and is being used gradually to substitute metals.

In the field of semiconductor and electric / electronic heat dissipation parts where the heat sink should not cause electrical interference, it is necessary to satisfy not only the function of effectively transmitting the heat of the heating body to the outside but also the electric insulation property so as not to cause electric interference from the heating body.

A composition obtained by compounding a plurality of materials in one can have characteristics that can not be obtained from each material, and the possibility of utilizing the heat sink is expected.

Registered Patent Publication No. 10-1470829 (Date of Notification: December 19, 2014)

In order to solve the above problems, the present invention provides a high thermal conductive electric insulating composition having improved thermal conductivity and electrical insulation by filling carbon nanotubes in alumina voids, a polymer molding produced from the composition, and a method of manufacturing the same. There is a purpose.

It is another object of the present invention to provide a high thermal conductive electrical insulating composition which improves the moldability and workability of a heat-radiating material and improves the thermal conductivity by improving the bonding area with the heat-generating material, and a polymer molding produced from the composition. have.

In order to achieve the above object, the present invention provides a high thermal conductivity electrically insulating composition comprising: alumina having a weight ratio of 93 to 97.5% by weight; And 2.5 to 7 wt%, and is made of CNT impregnated in the pores of the alumina.

(A) mixing 1 to 3 parts by weight of CNT with 100 parts by weight of a dispersion solvent, and simultaneously adding an external force and a rotational force to produce a CNT dispersion solution; (b) immersing 50 to 70 parts of alumina in 100 parts of the CNT dispersion solution, and then impregnating the voids of the alumina with CNT in the CNT dispersion solution; (c) removing the dispersion solvent from alumina impregnated with CNT; (d) removing CNT on the alumina surface.

Also, the polymer moldings prepared from the highly thermally conductive electrically insulative compositions according to the present invention may include a base material having a weight ratio of 50 to 70% by weight; And a high thermal conductivity electrically insulating filler having a weight ratio of 30 to 50% by weight, wherein said base material is at least one of engineering plastics having a thermal deformation temperature of 120 DEG C or higher based on ASTM D638 of 18.6 Kgf load standard Another feature.

The method for manufacturing a polymer molded article produced from the high thermal conductive electrical insulating composition according to the present invention comprises the steps of: (a) injecting a base material into a kneading extrusion molding machine to melt the base material at a melting temperature of 280 to 350 ° C; (b) In the step of melting the base material, a heat dissipating electrically insulating filler is charged into a material supplying device to form a base material having a weight ratio of 50 to 70% by weight and a heat dissipating electrically insulating filler having a weight ratio of 30 to 50% Preparing a resin composition containing a heat-dissipating electrically insulating filler; (c) forming the resin composition containing the heat-dissipating electrically insulating filler into pellets by hot cutting; (d) air-cooling the pellets to transfer the pellets to a predetermined position, and then packing the pellets.

The high thermal conductive electric insulating composition according to the present invention has high thermal conductive carbon nanotubes having a wide specific surface area in the electrically insulating alumina having voids, thereby enhancing heat conductivity and electric insulation, that is, As shown in Fig.

In addition, the high thermal conductive electric insulating composition according to the present invention can impregnate CNT into the pores of alumina, which acts as a heat resistor which is difficult to move the phonon during heat transfer, thereby reducing the volume of the pores, Can be increased.

In addition, the high thermal conductive electric insulating composition according to the present invention improves the integrity between the alumina and the carbon nanotube by uniformly impregnating the carbon nanotubes in the voids of the alumina without directionality, and can improve the thermal conductivity and the electric insulation property uniformly.

Also, the high thermal conductive electric insulating composition according to the present invention has the electric insulating property of alumina as a carrier, and has the advantage of simultaneously exhibiting thermal conductivity and electric insulating effect.

The polymer moldings prepared from the high thermal conductive electrical insulating composition according to the present invention can be utilized as a housing of a component material having a lot of heat generation or an interface plate material. In this case, since it has not only good thermal conductivity characteristics but also electrical insulation, Safety, performance, and reliability.

Further, the polymer molded product manufactured from the high thermal conductive electric insulating composition according to the present invention can be manufactured by using an engineering plastic excellent in moldability and workability and made into a pellet excellent in heat transfer and electrical insulation characteristics, Making it possible to use in various fields such as heat control materials.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a process diagram showing a method for producing a high thermal conductive electric insulating composition according to an embodiment of the present invention;
2 is a process chart showing a method of manufacturing a high thermal conductive electric insulating polymer molded article according to an embodiment of the present invention,
3 is an electron micrograph of a high thermal conductive electrical insulating composition (HCIA) according to an embodiment of the present invention,
4 is an electron micrograph of a high thermal conductive electric insulating polymer molded article according to an embodiment of the present invention.

The specific structure or functional description presented in the embodiment of the present invention is merely illustrative for the purpose of describing an embodiment according to the concept of the present invention, and embodiments according to the concept of the present invention can be implemented in various forms. It is to be understood that the invention is not to be construed as limited to the embodiments set forth herein, but includes all modifications, equivalents, and alternatives falling within the spirit and scope of the invention.

Hereinafter, the present invention will be described in detail.

An embodiment of the present invention provides a High thermally Conductive electrically Insulative Alumina composition (HCIA). The high thermal conductive electrical insulating composition (HCIA) may be constituted by a weight ratio of 93 to 97.5% by weight of alumina and a weight ratio of 2.5 to 7% by weight of carbon nanotubes (CNT) Lt; RTI ID = 0.0 > alumina voids. ≪ / RTI >

Hereinafter, the present invention will be described in detail.

An embodiment of the present invention provides a High thermally Conductive electrically Insulative Alumina composition (HCIA). The high thermal conductive electrical insulating composition (HCIA) may be constituted by a weight ratio of 93 to 97.5% by weight of alumina and a weight ratio of 2.5 to 7% by weight of carbon nanotubes (CNT) Lt; RTI ID = 0.0 > alumina voids. ≪ / RTI >

In this case, it is preferable that the CNT is composed of 2.5 to 7% by weight based on the total weight of the high thermal conductive electric insulating composition (HCIA). If the content of CNT is lower than the lower limit of 2.5% by weight, the effect of improving the thermal conductivity can not be obtained. If the content of CNT is higher than 7% by weight of the upper limit of the range, It may have a problem of deteriorating. And thus has a critical significance in the range of 2.5 to 7 wt% of the CNT.

It is preferable to use alumina particles having an average particle size of 100 μm to 500 μm and an alumina void having an average particle size of 5 μm to 10 μm inside alumina particles. The alumina preferably has a specific surface area in the void of 1.0 m ² / g to 1.5 m ² / g.

In this case, alumina has voids of 5 μm to 10 μm in the inside of the alumina particles. Practically useful thermal conductivity is difficult to obtain when the average pore range is lower than the upper average pore range. In the case where the thermal conductivity is higher than the upper limit, It is difficult to uniformly maintain the thickness of the glass, and the electrical insulation may be deteriorated. Thus, alumina voids have critical significance at 5 μm to 10 μm.

The CNT is added to the dispersion solvent in an amount of 1 to 3 parts by weight based on 100 parts by weight of the dispersion solvent, and the CNT can be introduced into the pores of the alumina while being cut and dispersed in the dispersion solvent.

As described above, the high thermal conductive electric insulating composition (HCIA) according to the embodiment of the present invention can be manufactured by impregnating CNT into the pores of alumina serving as a heat resistor which is difficult to move the phonon during heat transfer, By allowing movement, it has an advantage that the thermal conductivity can be increased.

As the dispersion solvent, it is preferable to use an alcohol-based or aromatic ring compound. The CNT is impregnated into the alumina void by using the volatilized property of the alcohol-based or aromatic ring compound, and then the dispersion solvent is effectively removed.

It is preferable that CNTs are cut and dispersed simultaneously. An CNT dispersion solution can be prepared by simultaneously applying an external force and a rotational force to the CNTs by irradiating ultrasonic waves of 40 to 50 kHz and rotating the agitator at 5,000 to 10,000 rpm . The cutting and dispersion time is preferably 30 to 120 minutes.

By cutting and dispersing the CNTs, the CNTs are densely adsorbed in the alumina voids without directionality.

On the other hand, the composition according to the embodiment of the present invention manufactured by the above method and the carbon nanotube are not used, or the composition is prepared in the form of a filler from the comparative example composition in which the content ratio is outside the numerical range of the present invention, Respectively.

As a comparative example according to an embodiment of the present invention, a high thermal conductive electric insulating composition (HCIA) according to the content ratio of alumina and CNT was prepared, and thermal conductivity and volume resistivity thereof were measured. Table 1 below is shown below.

Table 1 shows an example of changes in thermal conductivity and electrical insulation according to changes in the content of alumina and CNT when an ultrasonic wave is stirred at 7,500 rpm by a high-speed stirrer at an intensity of 45 kHz.

The thermal conductivity was measured using KSL 1604 and laser press. The volume resistivity was measured by ASTM D257, and the test specimens prepared by each composition were prepared as filler.

Composition Comparison 1 Comparison 2 Comparison 3 Comparison 4 Compare 5 Compare 6 Al ₂ O ₃ content (wt%) 100.00 99.70 99.50 99.00 98.50 98.00 CNT content (wt%) 0.00 0.30 0.50 1.00 1.50 2.00 Thermal conductivity (W / mK) 24.8 32.39 41.73 55.7 102 135 Volume Resistance (W / mK) over
-current over
-current over
-current 8.2 E + 14 2.1 E + 12 5.5 E + 9 Composition Practice 1 Practice 2 Practice 3 Practice 4 Conduct 5 Conduct 6 Al ₂ O ₃ content (wt%) 97.50 97.00 96.50 96.00 95.50 95.00 CNT content (wt%) 2.50 3.00 3.50 4.00 4.50 5.00 Thermal conductivity (W / mK) 169 181 186 188 204 221 Volume Resistance (W / mK) 3.0 E + 8 2.3 E + 7 4.2 E + 7 2.5 E + 7 5.4 E + 6 2.9 E + 5 Composition Practice 7 Practice 8 Conduct 9 Comparison 4 Compare 5 Compare 6 Al ₂ O ₃ content (wt%) 94.50 94.00 93.00 92.50 92.00 91.50 CNT content (wt%) 5.50 6.00 7.00 7.50 8.00 8.50 Thermal conductivity (W / mK) 220 232 245 270 315 339 Volume Resistance (W / mK) 1.2 E + 5 6.3 E + 4 4.3 E + 4 6.1 E + 3 1.0 E + 3 8.3 E + 2

As can be seen from the above Table 1, the thermal conductivity range of the high thermal conductive electric insulating composition (HCIA) according to the embodiment of the present invention is 169 to 245 W / mk, the volume resistance is 4.3E + 4 to 3.0E +8? M.

In order to increase the thermal conductivity, it is necessary to increase the content ratio of CNT and to increase the content of alumina in order to lower the electric conductivity. Therefore, according to the preferred embodiment of the present invention, high thermal conductivity and excellent electrical insulation can be obtained at a set content ratio of the high thermal conductive electrical insulating composition.

As described above, the high thermal conductive electric insulating polymer molded article according to the present invention has high thermal conductivity and can control the electric conductivity by improving the thermal conductivity and controlling the increase of the electric conductivity by impregnating the alumina void with CNT .

≪ Production Example of High Thermal Conductive Electrical Insulating Composition (HCIA) >

The present invention relates to a method for producing CNT dispersion, comprising the steps of: (a) mixing CNT into a dispersion solvent; (b) impregnating alumina in the CNT dispersion solution; (C) impregnating the CNT in the CNT dispersion solution, (c) removing the dispersion solvent from the CNT impregnated alumina, and (d) removing the CNT on the alumina surface. ). ≪ / RTI >

In step (a), the CNT is preferably mixed in an amount of 1 to 3 parts by weight based on 100 parts by weight of the dispersion solvent, and the CNT is dispersed in the CNT dispersion solution by simultaneously applying an external force and a rotational force. In particular, it is preferable to apply an external force and a rotational force for 30 to 120 minutes at the same time, by applying an ultrasonic wave of 40 to 50 kHz to rotate the external force and rotating the stirrer at 5,000 to 10,000 rpm.

(b) 100 parts of CNT dispersion solution After 50 to 70 parts of alumina is immersed in the skin, the CNT dispersion solution in which alumina is immersed is agitated at 100 to 300 rpm for 30 to 120 minutes to impregnate the pores of alumina with CNT .

In this case, it is preferable to use an alumina particle having an average particle size of 100 μm to 500 μm, and the alumina void is preferably 5 μm to 10 μm inside the alumina particle. The alumina preferably has a specific surface area in the void of 1.0 m ² / g to 1.5 m ² / g.

Furthermore, the water content of the alumina may limit the amount of impregnation of the CNT into the alumina void by blocking the alumina void, so that the moisture content of the alumina is preferably 0.1 parts by weight or less relative to 100 parts by weight of alumina.

Also, in step (b), in order to impregnate CNTs in the alumina void, it is preferable to stir the alumina-impregnated CNT dispersion solution at 100 to 300 rpm for 30 to 120 minutes.

The specific gravity of alumina is about 3.9, so that the alumina does not settle on the bottom by stirring at 100 to 300 rpm, and the possibility of contact of the alumina voids in the entire range of the CNT dispersion solution is increased. That is, through agitation, the possibility of adsorption of CNT in the alumina void is maintained.

In the step (c), it is preferable to carry out the drying step twice in order to remove the dispersion solvent. (c1) drying by hot air drying for 2 to 4 hours at a temperature below the boiling point of the dispersion solvent, and (c2) dehydration drying at a temperature of 100 to 150 ° C for 4 to 6 hours.

In the hot air drying step, it is preferable to remove the dispersion solvent at a temperature below the boiling point of the dispersion solvent. At the temperature above the boiling point of the dispersion solvent at the time of hot air drying, the CNT dispersion solution impregnated in the alumina pores expands and can be ejected out of the pores with a strong attraction force. Therefore, So that it does not flow to the outside. For example, when the dispersing solvent is used for alcohol-based ethanol, it can be hot-air dried at a temperature of 50 to 60 ° C. However, the temperature of 50 to 60 DEG C is an example of the temperature below the boiling point of the ethanol solvent, and a temperature below the boiling point of each dispersion solvent is sufficient.

In the dehumidifying and drying step, hydrolysis of the highly heat conductive electrically insulating composition (HCIA) by moisture is performed by maintaining the water content to 0.1 part by weight or less based on 100 parts by weight of alumina in order to increase the possibility of adsorption of CNTs in the CNT dispersion solution in alumina voids .

Even if the dispersion solvent is removed through the drying step, the CNT impregnated in the alumina void remains in the alumina void in the form of a needle, which can improve thermal conductivity and electrical insulation.

The step (d) may physically remove the CNT on the alumina surface by applying a lateral vibration of 250 to 400 vibrations / minute by a vibrator.

Another embodiment of the present invention provides a polymer molding (hereinafter, referred to as a 'high thermal conductive electric insulating polymer molding product') produced from a high thermal conductive electric insulating composition (HCIA). The high thermal conductive electrically insulating polymer moldings may comprise a known material and a high thermal conductivity electrically insulating filler. Further, functional additives can be included as needed.

In this case, the base material may have a weight ratio of 50 to 70% by weight, and the high thermal conductive electrically insulating filler may have a weight ratio of 30 to 50% by weight.

The base material is made of at least one of engineering plastics having a thermal deformation temperature of 120 DEG C or higher based on ASTM D638 of 18.6 Kgf load standard, and is made of at least one of nylon-6 (PA6), nylon-6.6 (PA66), polybutylene terephthalate Polybutylene terephthalate (PBT), polyetherimide (PEI), liquid crystal polymer (LCP), or a mixture thereof.

The high thermal conductive electrical insulating composition is characterized by having a weight ratio of from 93 to 97.5% by weight of alumina to a weight ratio of from 2.5 to 7% by weight of CNT, and is localized (impregnated) in the pores of the alumina. That is, it is characterized by having a weight ratio of 50 to 70 wt% of the base material, 27.9 to 48.75 wt% of alumina, and 1.25 to 2.1 wt% of CNT.

In this case, it is preferable to use an alumina particle having an average particle size of 100 μm to 500 μm, and the alumina void is preferably 5 μm to 10 μm inside the alumina particle. In addition, alumina is preferably used in that the specific surface area within the pore 1.0 m ² / g to 1.5 xm in ² / g.

Further, the functional additive may include a combination of a flame retardant and a heat stabilizer, a mold and a mixture of antioxidants, and a combination thereof in a known amount of action, for imparting functions of flame retardancy, thermal stability, oxidation resistance, etc. to the high thermal conductive electrical insulating polymer molding . For example, the flame retardant may include, but is not limited to, organic compounds including phosphorus, bromine, and / or chlorine, inorganic flame retardants, and halogenated materials. Heat stabilizers include, but are not limited to, phenolic stabilizers, organic thioether stabilizers, organic phosphite stabilizers, hindered amine stabilizers, epoxy stabilizers, and mixtures thereof. Further, the functional additive is not critical to the composition of the present invention.

On the other hand, Comparative Example in which the content ratio of the high thermal conductive electric insulating polymer molded article to the base material and the high thermal conductive electric insulating composition (HCIA) according to the embodiment of the present invention manufactured by the above- The results were compared and measured.

The thermal conductivity and the volume resistance were measured from the comparative example according to the embodiment of the present invention and are shown in Table 2 below.

The thermal conductivity was measured using KSL 1604 and laser press. The volume resistivity was measured by ASTM D257, and the test specimens prepared by each composition were prepared as flat plates.

Molding Comparison 1 Comparison 2 Comparison 3 Comparison 4 Compare 5 Compare 6 NYLON 66 (wt%) 40 Al ₂ O ₃ (wt%) 60.00 58.20 57.60 57.00 55.20 54.00 CNT (wt%) - 1.80 2.40 3.00 4.80 6.00 Thermal conductivity (W / mK) 0.68 1.89 2.86 3.42 3.88 4.06 Volumetric Resistance (Ωm) over-current 3.8 E + 14 1.7 E + 13 8.3 E + 13 4.4 E + 12 5.9 E + 11 Molding Compare 7 Practice 1 Practice 2 Practice 3 Compare 8 Compare 9 NYLON 66 (wt%) 50 Al ₂ O ₃ (wt%) 50.00 48.75 48.40 48.00 47.00 45.00 CNT (wt%) - 1.25 1.60 2.00 3.00 5.00 Thermal conductivity (W / mK) 0.63 1.79 2.44 2.86 3.21 3.58 Volumetric Resistance (Ωm) over-current over-current over-current over-current 3.3 E + 14 1.2 E + 13 Molding Compare 10 Practice 4 Conduct 5 Conduct 6 Comparison 11 Comparison 12 NYLON 66 (wt%) 60 Al ₂ O ₃ (wt%) 40.00 38.70 38.40 38.00 37.50 36.00 CNT (wt%) - 1.30 1.60 2.00 2.50 4.00 Thermal conductivity (W / mK) 0.58 1.46 1.89 2.18 2.56 2.97 Volumetric Resistance (Ωm) over-current over-current over-current over-current 7.3 E + 14 1.5 E + 14 Molding Compare 13 Practice 7 Practice 8 Conduct 9 Comparison 14 Compare 15 NYLON 66 (wt%) 70 Al ₂ O ₃ (wt%) 30.00 28.40 28.20 27.90 27.60 27.00 CNT (wt%) - 1.60 1.80 2.10 2.40 3.00 Thermal conductivity (W / mK) 0.52 1.05 1.12 1.32 1.39 1.53 Volumetric Resistance (Ωm) over-current over-current over-current over-current 7.8 E + 15 2.7 E + 15 Molding Compare 16 Compare 17 Compare 18 Compare 19 Compare 20 Comparison 21 NYLON 66 (wt%) 80 Al ₂ O ₃ (wt%) 20.00 19.40 19.20 19.00 18.40 18.00 CNT (wt%) - 0.60 0.80 1.00 1.60 2.00 Thermal conductivity (W / mK) 0.41 0.55 0.65 0.69 0.74 0.77 Volumetric Resistance (Ωm) over-current over-current over-current over-current over-current over-current

As can be seen from the above Table 2, in the high thermal conductive electric insulating polymer molded article according to the embodiment of the present invention, the content of the base material of NYLON 66 and the content of alumina and CNT in a set range such as stirring of ultrasonic wave of 45 kHz and 7,500 rpm The polymer moldings were prepared at different ratios.

It can be seen that the thermally conductive electrically insulating polymer molded article according to the embodiment of the present invention has higher thermal conductivity than the comparative example and also has a higher volume resistivity than the comparative example in accordance with the amount of CNT impregnated into the alumina pore That is, electrical insulation can be obtained. That is, it has been confirmed that, in the case of the present invention, the thermal conductivity can be improved and the electrical insulation can be achieved at the same time. The thermal conductivity range of the high thermal conductive electrical insulating polymer molded article according to the embodiment of the present invention is 1.05 to 2.83 W / mK, and the volume resistance is represented by over current (insulation).

As described above, the high thermal conductive electric insulating polymer molded article according to the present invention has high heat conductivity, and thus has excellent heat resistance, and it controls electric conductivity to prevent electricity from passing therethrough. In addition, It is possible to increase the adhesiveness to the element and to dissipate heat generated by the heat dissipation element quickly to the outside without electricity.

≪ Example of production of high thermal conductive electrical insulating polymer molded article >

The present invention relates to a method for producing a base material, comprising the steps of: (a) introducing a base material into a kneading extrusion molding machine to melt the base material at a melting temperature of 280 to 350 ° C; (b) (C) hot cutting the base material containing the high thermal conductive electrical insulating composition to form pellets, (d) air-cooling the pellets to move them to a predetermined position, and then packing them. , And a method of manufacturing a high thermal conductive electrical insulating polymer molding.

In the step (a), the base material is composed of at least one of engineering plastics having a thermal deformation temperature of 120 ° C or higher based on ASTM D638 of 18.6 Kgf load standard. The base material is melted and kneaded at a melting temperature of 280 to 350 ° C, .

In the step (b), a high thermal conductive electric insulating composition is added to the resin composition to prepare a high thermal conductive electric insulating composition containing a high thermal conductive electric insulating composition in a weight ratio of 30 to 50% by weight of the high thermal conductive electric insulating composition in a weight ratio of 50 to 70% Thereby producing a highly heat conductive electrically insulating polymer molding.

In this case, it is preferable that the base material is constituted by a weight ratio of 50 to 70% by weight based on the total weight of the high thermal conductive electrically insulating polymer molded product. If the content of the base material is lower than 50% by weight, which is the lower limit of the upper range, moldability and workability are remarkably lowered. If it is higher than the upper limit of 70% by weight, moldability and workability in a desired shape are improved, There is a problem that the electrical insulation is deteriorated. Thus, the numerical range of the known material has a critical significance at 50 to 70% by weight.

Since the high thermal conductive electric insulating filler is formed by the same physical properties as the high thermal conductive electric insulating composition (HCIA), its abuse is omitted.

When the pellet is formed in step (c), an undercut, that is, hot cut, which cuts directly from the extruder nozzle to maintain the shape of the string, is performed.

The pellets are hot-cut. In this case, in general, plastic polymer pellets are formed continuously by a cutting machine after forming a string of strings and cooling, but the pellets made of a highly heat conductive electrically insulating polymer molding material have superior heat dissipation performance compared to generalplasticic polymers It is cooled as soon as it is exposed to the atmosphere from the extruder nozzle. Due to the characteristics of the thermally conductive polymer, it is preferable to form a string by a hot cutting method which can be made into pellets directly at the nozzle outlet.

As described above, the high thermal conductive electrical insulating polymer molded article according to the embodiment of the present invention is manufactured by using engineering plastic excellent in moldability and workability and made of pellets excellent in heat transfer and electrical insulation characteristics, Making it possible to use in various fields such as heat control materials.

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 or scope of the inventions. It will be apparent to those of ordinary skill in the art.

Claims (13)

delete delete delete (a) mixing 1 to 3 parts by weight of CNT with 100 parts by weight of a dispersion solvent, and simultaneously applying an external force and a rotational force to produce a CNT dispersion solution;
(b) immersing 50 to 70 parts of alumina in 100 parts of the CNT dispersion solution, and then impregnating the voids of the alumina with CNT in the CNT dispersion solution;
(c) removing the dispersion solvent from alumina impregnated with CNT;
(d) removing CNT on the alumina surface. < RTI ID = 0.0 > 11. < / RTI > 5. The method of claim 4,
Wherein the alumina has a particle size of 100 μm to 500 μm and a pore size of 5 μm to 10 μm, a specific surface area of 1.0 m ² / g to 1.5 m ² / g in the pore, a water content of 0.1 wt. Lt; RTI ID = 0.0 > 1, < / RTI > 5. The method of claim 4,
The step (a)
The external force was determined by ultrasonic irradiation at 40 to 50 kHz,
The rotation force is obtained by rotating the stirrer at 5,000 to 10,000 rpm,
Wherein the external force and the rotational force are applied for 30 to 120 minutes to produce a CNT dispersion solution. The method according to claim 4 or 5,
The step (b)
The CNT dispersion solution in which the alumina was immersed was aged for 30 to 120 minutes And stirring the mixture at 100 to 300 rpm to impregnate the pores of the alumina with CNTs. 5. The method of claim 4,
The step (c)
(c1) A primary drying step of hot-air drying at a temperature below the boiling point for 2 to 4 hours;
(c2) a secondary drying step of dehumidifying and drying at a temperature of 100 to 150 DEG C for 4 hours to 6 hours. 5. The method of claim 4,
The step (d)
And removing the CNT on the alumina surface by applying a left / right vibration of 250 to 400 vibrations / minute by a vibrator. delete delete delete (a) introducing a base material into a kneading extrusion molding machine to melt the base material at a melting temperature of 280 to 350 ° C;
(b) In the step of melting the base material, a high thermal conductive electric insulating filler is charged into a material supply device to produce a base material having a weight ratio of 50 to 70% by weight and a high thermal conductive electric material having a weight ratio of 30 to 50% Preparing a resin composition containing an insulating filler, the resin composition containing a high thermal conductive electric insulating filler;
(c) forming the resin composition containing the high thermal conductive electrically insulating filler into pellets by hot cutting;
(d) air-cooling the pellet to transfer it to a predetermined position, and then packing the pellet.

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