KR20130088251A - Polymer composition with high thermal conductivity and manufacturing method of the same - Google Patents

Abstract

PURPOSE: A thermal conductive composite material composition is provided to catapult an overmold, lighten weight, reduce the battery capacity of an electro-mobile, and to extend the battery life. CONSTITUTION: A thermal conductive composite material composition comprises: more than one kind of thermoplastic resin selected from among polyolefin group resin, polyamide group resin, polybutyleneterephthalate group resin, acrylonitrile-butadiene-styrene copolymer, polycarbonate group resin, polyester group resin, polyphenylenesulfide group resin, and thermoplastic elastomer resin; more than one kind of thermoplastic filler selected from the expanded graphite and boriding nitrogen which are distributed in the thermoplastic resin discontinuously and uniformly; and long fiber, which is distributed in the thermoplastic resin discontinuously and uniformly, has rectangularity ratio of 50-3000.

Description

Polymer composition with high thermal conductivity and manufacturing method of the same

The present invention relates to a thermally conductive composite material composition and a method of manufacturing the same, and more particularly, to compensate for the disadvantages of aluminum used as a cooling fin and to reduce the weight as an interface material or a package material that acts as an intermediary to directly contact a lithium battery. The present invention relates to a thermally conductive composite material composition and a method of manufacturing the same that can extend the life of an electric vehicle battery.

Thermal control component materials for electric vehicles are collectively referred to as smart component materials that control the heat generated from lithium batteries for the life cycle and safety of high capacity electric vehicle battery packages.

The development of electric vehicle batteries is rapidly progressing around lithium battery packages, which are advantageous in fast charging, high output, and repeated charging times. The battery pack currently used in Tesla's high-speed electric vehicles in the United States is a large-capacity energy storage system (ESS) that connects thousands of small lithium batteries used in existing computers or mobile phones in the form of modules. The heat generated from each battery during the high-capacity output of the car causes local temperature differences or thermal runaway, which hinders the efficiency and stability of the battery due to high heat during high-power driving. Thermal runaway is caused by a lack of heat diffusion to the outside than the heat generated inside the battery, and it causes decomposition that causes leakage of the battery electrolyte, smoke generation, gas generation, ignition, and rapid decomposition. In order to control the heat generated by the chemical reaction inside the battery and the spatial arrangement of the battery, advanced electric vehicle or battery module companies are actively developing package technology for shortening the charging time, improving the output and extending the battery life. .

There is a need for a technique for controlling thermal runaway, which is mainly caused by rapid power output, overcharging, external temperature, collision breakdown, and external energization, and development of economical thermal control device is essential. It is true.

In order to improve battery life and efficiency, the temperature inside the package should be maintained under 40 ℃ or below -10 ℃ and the heat dissipation between each battery should be kept constant. Rather, it uses a forced heat exchange method that wraps the battery with a metal cooling plate such as aluminum and circulates the refrigerant inside or outside the aluminum. However, aluminum is a material with high thermal conductivity of about 200 W / m · K, but since it is not insulating, thousands of fuses are used to secure stability, and the elasticity and grip required for battery modularization are insufficient. Therefore, it is required to develop new thermally conductive materials to supplement and replace them.

Republic of Korea Patent Registration No. 10-0998619

The problem to be solved by the present invention is to supplement the shortcomings of the aluminum used as the cooling fins and to reduce the weight as an interface material or a package material that acts as an intermediary to directly contact the lithium battery can extend the life of the electric vehicle battery It is to provide a thermally conductive composite material composition and a method of manufacturing the same.

The present invention is a polyolefin resin, polyamide resin, polybutylene terephthalate resin, acrylonitrile butadiene styrene copolymer, polycarbonate resin, polyester resin, polyphenylene sulfide resin and thermoplastic elastomer resin Discontinuously and uniformly dispersed in one or more selected thermoplastic resins and one or more thermally conductive fillers selected from expanded graphite and nitrogen boride discontinuously and uniformly dispersed in the thermoplastic resin and the thermoplastic resin And a long fiber having a square ratio of 50 to 3000, wherein the thermally conductive filler contains 0.1 to 90 parts by weight based on 100 parts by weight of the thermoplastic resin, and the long fiber is 0.1 to 90 parts by weight based on 100 parts by weight of the thermoplastic resin. It provides a thermally conductive composite composition containing parts by weight.

The thermally conductive composite material composition may further include carbon nanotubes discontinuously and uniformly dispersed in the thermoplastic resin, wherein the carbon nanotubes are contained in an amount of 0.1 to 10 parts by weight based on 100 parts by weight of the thermoplastic resin. desirable.

The thermally conductive composite material composition may further include nanoclays discontinuously and uniformly dispersed in the thermoplastic resin, and the nanoclay is preferably contained in an amount of 0.1 to 10 parts by weight based on 100 parts by weight of the thermoplastic resin. .

The thermally conductive composite material composition may further include at least one material selected from talc and calcium carbonate discontinuously and uniformly dispersed in the thermoplastic resin, and at least one material selected from the talc and calcium carbonate is a thermoplastic resin. It is preferable to contain 0.1-10 weight part with respect to 100 weight part.

The thermally conductive composite material composition may further include an organic nucleating agent discontinuously and uniformly dispersed in the thermoplastic resin, the organic nucleating agent is contained 0.1 to 10 parts by weight based on 100 parts by weight of the thermoplastic resin, the organic Nucleating agents may include organocarboxylates or organophosphates.

The thermally conductive composite material composition may further include a rubber discontinuously and uniformly dispersed in the thermoplastic resin, and the rubber is preferably contained 5 to 40 parts by weight based on 100 parts by weight of the thermoplastic resin.

The expanded graphite may be made of powder-type expanded graphite having graphite connected to each other by being separated at a temperature higher than 300 ° C. after the graphite is purified with sulfuric acid, hydrogen peroxide, and NH ₄ S ₂ O ₈ .

In addition, the expanded graphite is a graphite plate peeled off with the expanded particulate graphite having a soft particulate form formed by compacting the powdered expanded graphite may have a crystal size of 10 ~ 200nm.

The nitrogen boride may be composed of a nitrogen boride-based composite formed by hybridization of nitrogen boride and magnesium oxide (MgO), and the magnesium oxide may be 5 to 40 weight parts based on 100 parts by weight of nitrogen boride in the nitrogen-boron-based composite. It is preferable to contain a part.

The long fiber may be made of one or more long fibers selected from glass fibers, carbon fibers, and organic fibers, and the long fibers preferably have a length of 0.1-20 mm.

Moreover, this invention is (a) polyolefin resin, polyamide resin, polybutylene terephthalate resin, acrylonitrile butadiene styrene copolymer, polycarbonate resin, polyester resin, polyphenylene sulfide resin And injecting at least one thermoplastic resin selected from the thermoplastic elastomer resins into the twin screw extruder, and (b) rotating the shaft to mix the thermoplastic resin in the cylinder of the twin screw extruder while being higher than the melting temperature of the thermoplastic resin. Melting and compressing at a temperature, and (c) rotating the shafts of the twin screw extruder in a predetermined direction so that shear stress is applied to the molten and compressed thermoplastic resin and selected from expanded graphite and nitrogen boride. One or more thermally conductive fillers and long fibers having a square ratio of 50 to 3000 Added through an id feeder to uniformly disperse in the thermoplastic resin, and (d) twin screw by rotating the shaft to apply a higher shear stress in step (c) while heating to a higher temperature than step (c). Ejecting the composition from an extruder and (e) cooling and cutting to obtain a thermally conductive composite material composition, wherein the thermally conductive filler is added in an amount of 0.1 to 90 parts by weight based on 100 parts by weight of the thermoplastic resin, and the long fibers Provides a method for producing a thermally conductive composite material composition is added 0.1 to 90 parts by weight based on 100 parts by weight of a thermoplastic resin.

Moreover, this invention is (a) polyolefin resin, polyamide resin, polybutylene terephthalate resin, acrylonitrile butadiene styrene copolymer, polycarbonate resin, polyester resin, polyphenylene sulfide resin And (b) producing a resin-long fiber composite material in which long fibers having a square ratio of 50 to 3000 are discontinuously and uniformly dispersed in at least one thermoplastic resin selected from thermoplastic elastomer resins. At least one thermoplastic resin selected from a resin, a polybutylene terephthalate resin, an acrylonitrile butadiene styrene copolymer, a polycarbonate resin, a polyester resin, a polyphenylene sulfide resin, and a thermoplastic elastomer resin, and the resin-sheet Feeding the fiber composite to a twin screw extruder, and (c) the shaft Rotating and melting and compressing the thermally conductive resin and the resin-long fiber composite in a cylinder of the twin screw extruder at a temperature higher than the melting temperature of the thermoplastic resin, and (d) the shaft of the twin screw extruder; Are rotated in a predetermined direction so that the shear stress is applied to the melted and compressed resultant, and at least one thermally conductive filler selected from expanded graphite and nitrogen boride is added through a side feeder to uniformly disperse the thermoplastic resin. Discharging the composition in a twin screw extruder by rotating the shaft to (e) apply a higher shear stress in step (d) while heating to a temperature higher than step (d), and (f) cooling and Cutting to obtain a thermally conductive composite composition, wherein the thermally conductive filler is thermal Relative to 100 parts by weight of plastic resin to be contained 0.1 to 90 parts by weight, the long-fiber provides a method of manufacturing the heat-conductive composite material containing a composition to be from 0.1 to 90 parts by weight per 100 parts by weight of the thermoplastic resin.

Moreover, this invention is (a) polyolefin resin, polyamide resin, polybutylene terephthalate resin, acrylonitrile butadiene styrene copolymer, polycarbonate resin, polyester resin, polyphenylene sulfide resin And preparing a thermally conductive composite in which at least one thermally conductive filler selected from expanded graphite and nitrogen boride is discontinuously and uniformly dispersed in at least one thermoplastic resin selected from thermoplastic elastomer resins, and (b 1 type selected from polyolefin resin, polyamide resin, polybutylene terephthalate resin, acrylonitrile butadiene styrene copolymer, polycarbonate resin, polyester resin, polyphenylene sulfide resin, and thermoplastic elastomer resin Long fibers having a square ratio of 50 to 3000 in the above thermoplastic resin Preparing a disperse and uniformly dispersed resin-long fiber composite; (c) feeding the thermally conductive composite and the resin-long fiber composite into a twin screw extruder; and (d) rotating the shaft. Melting and compressing the thermally conductive composite and the resin-long fiber composite in a cylinder of the twin screw extruder at a temperature higher than the melting temperature of the thermoplastic resin, and (e) maintaining the shafts of the twin screw extruder Direction so that the shear stress is applied to the melted and compressed product so that the thermally conductive filler and the long fibers are uniformly dispersed in the thermoplastic resin, and (f) is heated to a temperature higher than the step (e) In the twin screw extruder by rotating the shaft to apply a higher shear stress in step (e) Discharging and (g) cooling and cutting to obtain a thermally conductive composite material composition, wherein the thermally conductive filler is contained in an amount of 0.1 to 90 parts by weight based on 100 parts by weight of the thermoplastic resin, and the long fiber is a thermoplastic resin. Provided is a method for producing a thermally conductive composite composition containing 0.1 to 90 parts by weight based on 100 parts by weight.

Moreover, this invention is (a) polyolefin resin, polyamide resin, polybutylene terephthalate resin, acrylonitrile butadiene styrene copolymer, polycarbonate resin, polyester resin, polyphenylene sulfide resin And preparing a thermally conductive composite in which at least one thermally conductive filler selected from expanded graphite and nitrogen boride is discontinuously and uniformly dispersed in at least one thermoplastic resin selected from thermoplastic elastomer resins, and (b 1 type selected from polyolefin resin, polyamide resin, polybutylene terephthalate resin, acrylonitrile butadiene styrene copolymer, polycarbonate resin, polyester resin, polyphenylene sulfide resin, and thermoplastic elastomer resin Long fibers having a square ratio of 50 to 3000 in the above thermoplastic resin Preparing a disperse and uniformly dispersed resin-long fiber composite; (c) injecting and mixing the thermally conductive composite and the resin-long fiber composite into an injection molding machine; and (d) the composition in the injection molding machine. (E) cooling to obtain a thermally conductive composite material composition, wherein the thermally conductive filler is contained in an amount of 0.1 to 90 parts by weight based on 100 parts by weight of the thermoplastic resin, and the long fiber is made of thermoplastic resin 100. It provides a method for producing a thermally conductive composite material composition to be contained 0.1 to 90 parts by weight with respect to parts by weight.

The method of manufacturing the thermally conductive composite material composition may further include adding carbon nanotubes through a side feeder in a process of causing shear stress to be applied to the melted and compressed products, wherein the carbon nanotubes are thermoplastic. It is preferable to add 0.1-10 weight part with respect to 100 weight part of resin.

In addition, the method of manufacturing the thermally conductive composite material composition may further include adding nanoclay through a side feeder in a process of causing shear stress to be applied to the melted and compressed products, wherein the nanoclay is thermoplastic It is preferable to add 0.1-10 weight part with respect to 100 weight part of resin.

In addition, the method of manufacturing the thermally conductive composite material composition, further comprising the step of adding at least one material selected from talc and calcium carbonate through a side feeder in the course of applying a shear stress to the melted and compressed product. The at least one material selected from talc and calcium carbonate may be added in an amount of 0.1 to 10 parts by weight based on 100 parts by weight of the thermoplastic resin.

In addition, the method of manufacturing the thermally conductive composite material composition may further include adding an organic nucleating agent through a side feeder in a process of causing shear stress to be applied to the melted and compressed products, wherein the organic nucleating agent is thermoplastic. It is preferable to add 0.1-10 weight part with respect to 100 weight part of resin, and the said organic nucleating agent may contain an organic carboxylate or an organophosphate.

In addition, the manufacturing method of the thermally conductive composite material composition may further include the step of adding a rubber through the side feeder in the process of applying a shear stress to the melted and compressed product, the rubber is a thermoplastic resin 100 It is preferable to add 5-40 weight part with respect to a weight part.

The expanded graphite may be made of powder-type expanded graphite having graphite connected to each other by being separated at a temperature higher than 300 ° C. after the graphite is purified with sulfuric acid, hydrogen peroxide, and NH ₄ S ₂ O ₈ .

In addition, the expanded graphite is a graphite plate peeled off with the expanded particulate graphite having a soft particulate form formed by compacting the powdered expanded graphite may have a crystal size of 10 ~ 200nm.

The nitrogen boride may be composed of a nitrogen boride-based composite formed by hybridization of nitrogen boride and magnesium oxide (MgO), and the magnesium oxide may be 5 to 40 weight parts based on 100 parts by weight of nitrogen boride in the nitrogen-boron-based composite. It is preferable to contain a part.

The long fiber may be made of one or more long fibers selected from glass fibers, carbon fibers, and organic fibers, and the long fibers preferably have a length of 0.1-20 mm.

The step of preparing the resin-long fiber composite, polyolefin resin, polyamide resin, polybutylene terephthalate resin, acrylonitrile butadiene styrene copolymer, polycarbonate resin, polyester resin, polyphenylene Injecting at least one thermoplastic resin selected from sulfide resin and thermoplastic elastomer resin into a twin screw extruder, and rotating the shaft to mix the thermoplastic resin in the cylinder of the twin screw extruder while higher than the melting temperature of the thermoplastic resin. Melting and compressing at a temperature, rotating the shafts of the twin screw extruder in a predetermined direction so that shear stress is applied to the melted and compressed thermoplastic resin, and adding a long fiber having a square ratio of 50 to 3000 through a side feeder. Uniform in the thermoplastic resin Dispersing, discharging the resin-long fiber composite in a twin screw extruder by rotating the shaft to apply a higher shear stress in the dispersing step while heating to a higher temperature than the dispersing step, and cooling and cutting the resin It may include the step of obtaining a long fiber composite material, the long fiber is preferably added 0.1 to 90 parts by weight based on 100 parts by weight of a thermoplastic resin.

The step of preparing the thermally conductive composite, polyolefin resin, polyamide resin, polybutylene terephthalate resin, acrylonitrile butadiene styrene copolymer, polycarbonate resin, polyester resin, polyphenylene sulfide At least one thermoplastic resin selected from the group consisting of a resin and a thermoplastic elastomer resin is introduced into a twin screw extruder, and the shaft is rotated to mix the thermoplastic resin in a cylinder of the twin screw extruder at a temperature higher than the melting temperature of the thermoplastic resin. Melting and compressing, rotating the shafts of the twin screw extruder in a predetermined direction so that shear stress is applied to the molten and compressed thermoplastic resin, and at least one thermal conductivity selected from expanded graphite and nitrogen boride Filler Side Feeder Dispersing it uniformly in the thermoplastic resin, and rotating the shaft to apply a higher shear stress in the dispersing step while heating to a higher temperature than the dispersing step, thereby discharging the thermally conductive composite material from the twin screw extruder. It may include the step and cooling and cutting to obtain a thermally conductive composite, the thermally conductive filler is preferably added 0.1 to 90 parts by weight based on 100 parts by weight of the thermoplastic resin.

According to the present invention, an overmolding injection is possible and the weight of the electric vehicle battery can be compensated for as an interface material and an intermediate material that directly compensates for the disadvantages of aluminum used as a cooling fin and directly contacts a lithium battery. It is possible to obtain a thermally conductive composite composition capable of lowering the capacity and extending the life.

1 is a view showing a twin screw extruder.
2 is a view showing details of a shaft and a cylinder in a twin-screw extruder excluding the heating means.
FIGS. 3A and 3B are views showing a cylinder and a shaft portion of a twin screw extruder in detail.
4 is a view showing an example of a shaft of a twin screw extruder.
5 is a view showing the screw shaft of the molten and compressed region in detail.
6 is a view showing in detail the stepped screw of the kneading zone.
7 is a view showing in detail a part of the shaft of the dispersion region.
8 is a graph showing the effect of the thermal conductivity change and the addition of CNT according to the graphite content of the PBT / EGP thermally conductive composite.
9 is a graph of the in-plane thermal conductivity by the laser flash method according to the graphite content of the PA6 / EGG thermal conductive composite.
10 is a result of measuring the through-plane thermal conductivity by the laser flash method according to the graphite content of the PA6 / EGG thermal conductive composite material.
11 is a graph comparing the difference between the rubber content and the thermal conductivity evaluation method of the PA6 / EGG thermal conductive composite material.
12 is a graph showing a change in impact strength and flexural modulus according to the SG content of the PP / SG thermal conductive composite.
FIG. 13 is a graph showing a change in thermal conductivity of the TM1 evaluation method according to the graphite content of the PP / SG thermally conductive composite and the PP / EGG thermally conductive composite.
14 is a graph showing the impact strength and flexural modulus change according to the e-graphite content of the PP / EGG thermally conductive composite.
15 is a graph comparing the change in thermal conductivity of the PBT / BG10 thermally conductive composite according to the content of BG when the MWNT does not exist and the presence of MWNT.
16 is a graph showing the thermal conductivity change of the in-plane of TM-1 and the through-plane of TM-2 according to the BN content of the PA6 / BN10 thermally conductive composite.
17 is a graph showing changes in flexural modulus and impact strength according to BN content of PA6 / BN10 thermally conductive composites.
18 is a graph comparing the flexural modulus of the PA6 / BN10 thermally conductive composite and the PA6 / BG10 thermally conductive composite.
19 is a graph showing thermal conductivity according to BN content of a PP / BN thermally conductive composite and a PP / BG thermally conductive composite.
20 is a graph comparing flexural modulus and impact strength according to BN particle size of a PP / BN thermally conductive composite.
21 is a graph comparing flexural modulus and impact strength according to SGF and LGF of GF-reinforced resin-fiber composites of PP, PA6, and PA66.
22 is a graph comparing the thermal conductivity of the PP / EGG thermally conductive composite and the PP / EGG / LGF thermally conductive composite composition according to the e-graphite content.
FIG. 23 is a graph comparing the thermal conductivity of the PA6 / EGG thermally conductive composite and the PA6 / EGG / LGF thermally conductive composite composition.
24 is a graph comparing the thermal conductivity of the PP / BN / LGF thermally conductive composite composition and PA6 / BN / LGF thermally conductive composite composition by LGF strengthening.
FIG. 25 is a graph of comprehensively analyzing SFN and MFI according to BN content of PP / BN, PA6 / BN, PP / EGG, and PA6 / EGG thermally conductive composites.
FIG. 26 shows the change in SFN of PP / LGF composite and PA6 / LGF composite according to LGF content, and the variation of spiral flow number (SFN) of composite material in which LGF is reinforced in thermally conductive fillers having the maximum filling ratio of the corresponding resin. It is a graph.

Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the accompanying drawings. However, it should be understood that the following embodiments are provided so that those skilled in the art will be able to fully understand the present invention, and that various modifications may be made without departing from the scope of the present invention. It is not. Wherein like reference numerals refer to like elements throughout.

In the following description, nano is used to mean a size of 1 to 1,000 nm as a nanometer (nm) unit, and nanoclay refers to clay having a particle size of 1 to 1,000 nm. We use by doing.

The thermally conductive composite material composition according to a preferred embodiment of the present invention, polyolefin resin, polyamide resin, polybutylene terephthalate resin, acrylonitrile butadiene styrene copolymer, polycarbonate resin, polyester resin, At least one thermoplastic resin selected from polyphenylene sulfide resin and thermoplastic elastomer resin, at least one thermally conductive filler selected from expanded graphite and nitrogen boride discontinuously and uniformly dispersed in the thermoplastic resin, and Disperse and uniformly dispersed in the thermoplastic resin and comprises a long fiber having a square ratio of 50 to 3000, wherein the thermally conductive filler is contained 0.1 to 90 parts by weight based on 100 parts by weight of the thermoplastic resin, 0.1 to 90 parts by weight based on 100 parts by weight of the thermoplastic resin It can control.

The thermally conductive composite material composition may further include carbon nanotubes discontinuously and uniformly dispersed in the thermoplastic resin, wherein the carbon nanotubes are contained in an amount of 0.1 to 10 parts by weight based on 100 parts by weight of the thermoplastic resin. desirable.

Carbon nanotubes are rounded in a hexagonal network of carbon atoms. At this time, the end has a zigzag shape and an armrest chair shape according to the angle. In addition, the rounded shape takes the form of a single wall, which is a single wall structure, and a multi-wall structure having a plurality of walls. In addition, a single wall or a multi-walled structure may be used. Walls are bundled (Nano tube bundles), and metals (metal-atom-filled nano tubes) inside the tubes. When the carbon nanotubes are properly dispersed and added to the thermoplastic resin, mechanical properties such as flexural modulus (FM), flexural strength (FS), and tensile strength (TS) and thermal deformation temperature ( Improve heat resistance such as Heat Distortion Temperature (HDT).

The thermally conductive composite material composition may further include nanoclays discontinuously and uniformly dispersed in the thermoplastic resin, and the nanoclay is preferably contained in an amount of 0.1 to 10 parts by weight based on 100 parts by weight of the thermoplastic resin. .

The nanoclay may be composed of at least one nanoclay selected from nanoclays treated with silane and nanoclays treated with quaternary ammonium. The nanoclay treated with the silane refers to a nanoclay treated with a siloxane bond to a silanol of the nanoclay. In addition, the nanoclay treated with quaternary ammonium refers to a nanoclay treated by ion exchange of a cation and quaternary ammonium contained in the nanoclay.

The silane is, for example, octyltriethoxysilane, propyltriethoxysilane, phenylsilane, ethyltriethoxysilane, ethyltrimethoxysilane, methyltrimethoxysilane, methyltriethoxysilane, vinyltrimethoxy Silane, vinyltriethoxysilane, 3-aminopropyltrimethoxysilane, N- (2-aminoethyl) -3-aminopropyltriethoxysilane, aminopropyltriethoxysilane or derivatives thereof or mixtures thereof. It is not limited thereto.

The quaternary ammonium is, for example, trimethylalkylammonium, triethylalkylammonium, tributylalkylammonium, dimethyldialkylammonium, dibutyldialkylammonium, methylbenzyldialkylammonium, dibenzyldialkylammonium, trialkylmethylammonium Alkyl ammonium, such as trialkylethylammonium, trialkylbutylammonium, and the like, but is not limited thereto, and may be dialkyl quaternary ammonium, trialkyl quaternary ammonium, aromatic quaternary ammonium, heterocyclic quaternary ammonium, and the like. Here, alkyl may have an average carbon number of 1 to 30.

Nanoclays, when dispersed in a thermoplastic resin, have a thickness of at least 1 nm and a nano size of less than 1 μm. Nanoclays are Smectite, Montmorillonite, Hectorite, Saponite, Vermiculite, Beidelite, Kaolinite, Magadite ) Or mixtures thereof.

When the nanoclay is melted and extruded by a twin screw extruder, the nanoclay is peeled off by the shear stress caused by the shaft, and the content of the nanoclay is at least a certain amount (for example, at least 1% by weight). In this case, the platelets formed by peeling may be stuck together again or the peeling may be stopped due to insufficient space. Thus, the platelets formed by peeling the nanoclay are dispersed in the thermoplastic resin in a discontinuous form, and when the quench is discharged from the twin screw extruder, the nanoclay is peeled off to obtain a uniformly dispersed thermal conductive composition. By containing nanoclay, there is an advantage that can improve mechanical properties and heat resistance properties.

The thermally conductive composite material composition may further include at least one material selected from talc and calcium carbonate discontinuously and uniformly dispersed in the thermoplastic resin, and at least one material selected from the talc and calcium carbonate is a thermoplastic resin. It is preferable to contain 0.1-10 weight part with respect to 100 weight part.

The thermally conductive composite material composition may further include an organic nucleating agent discontinuously and uniformly dispersed in the thermoplastic resin, the organic nucleating agent is contained 0.1 to 10 parts by weight based on 100 parts by weight of the thermoplastic resin, the organic Nucleating agents may include organocarboxylates or organophosphates.

The thermally conductive composite material composition may further include a rubber discontinuously and uniformly dispersed in the thermoplastic resin, and the rubber is preferably contained 5 to 40 parts by weight based on 100 parts by weight of the thermoplastic resin.

The expanded graphite may be made of powder-type expanded graphite having graphite connected to each other by being separated at a temperature higher than 300 ° C. after the graphite is purified with sulfuric acid, hydrogen peroxide, and NH ₄ S ₂ O ₈ .

In addition, the expanded graphite is a graphite plate peeled off with the expanded particulate graphite having a soft particulate form formed by compacting the powdered expanded graphite may have a crystal size of 10 ~ 200nm.

The nitrogen boride may be composed of a nitrogen boride-based composite formed by hybridization of nitrogen boride and magnesium oxide (MgO), and the magnesium oxide may be 5 to 40 weight parts based on 100 parts by weight of nitrogen boride in the nitrogen-boron-based composite. It is preferable to contain a part.

The long fiber may be made of one or more long fibers selected from glass fibers, carbon fibers, and organic fibers, and the long fibers preferably have a length of 0.1-20 mm.

The thermally conductive composite material composition may further include a heat stabilizer (antioxidant), the heat stabilizer is preferably contained in 0.01 to 2 parts by weight based on 100 parts by weight of the thermoplastic resin.

In addition, the thermally conductive composite material composition may further include a lubricant, the lubricant is preferably contained in 0.01 to 2 parts by weight based on 100 parts by weight of the thermoplastic resin.

Method for producing a thermally conductive composite material composition according to an embodiment of the present invention, (a) polyolefin resin, polyamide resin, polybutylene terephthalate resin, acrylonitrile butadiene styrene copolymer, polycarbonate Injecting at least one thermoplastic resin selected from resins, polyester resins, polyphenylene sulfide resins and thermoplastic elastomer resins into a twin screw extruder, and (b) rotating the shaft to allow the twin screw extruder to Melting and compressing the thermoplastic resin at a temperature higher than the melting temperature of the thermoplastic resin, and (c) rotating the shafts of the twin screw extruder in a predetermined direction so that shear stress is applied to the molten and compressed thermoplastic resin. Among, expanded graphite and nitrogen boride Adding at least one thermally conductive filler and a long fiber having an angular ratio of 50 to 3,000 through a side feeder to uniformly disperse it in the thermoplastic resin, and (d) heating to a temperature higher than the step (c); c) rotating the shaft to apply a higher shear stress in step c) to eject the composition in a twin screw extruder; and (e) cooling and cutting to obtain a thermally conductive composite composition, wherein the thermally conductive filler is thermoplastic 0.1-90 weight part is added with respect to 100 weight part of resin, and the said long fiber is added 0.1-90 weight part with respect to 100 weight part of thermoplastic resins.

Method for producing a thermally conductive composite material composition according to another preferred embodiment of the present invention, (a) polyolefin resin, polyamide resin, polybutylene terephthalate resin, acrylonitrile butadiene styrene copolymer, polycarbonate A resin-long fiber composite material in which long fibers having a square ratio of 50 to 3000 are discontinuously and uniformly dispersed in one or more thermoplastic resins selected from resins, polyester resins, polyphenylene sulfide resins and thermoplastic elastomer resins. (B) polyolefin resin, polyamide resin, polybutylene terephthalate resin, acrylonitrile butadiene styrene copolymer, polycarbonate resin, polyester resin, polyphenylene sulfide resin and thermoplastic elastomer At least one thermoplastic resin selected from resins and said resin-sheet Feeding the oily composite into the twin screw extruder, and (c) rotating the shaft to mix the thermally conductive resin and the resin-long fiber composite in a cylinder of the twin screw extruder while at a temperature higher than the melting temperature of the thermoplastic resin. (D) rotating the shafts of the twin screw extruder in a predetermined direction so that shear stress is applied to the melted and compressed product, and selected from expanded graphite and nitrogen boride. Adding the above-mentioned thermally conductive fillers through a side feeder to uniformly disperse them in the thermoplastic resin, and (e) heating the shaft to a higher temperature than step (d) while applying a higher shear stress in step (d). Rotating to eject the composition from the twin screw extruder and (f) cooling and cutting to Comprising the step of obtaining the material composition, the thermally conductive filler allows the chapter to be contained 0.1 to 90 parts by weight per 100 parts by weight of the thermoplastic resin, the fibers contain from 0.1 to 90 parts by weight per 100 parts by weight of the thermoplastic resin.

Method for producing a thermally conductive composite material composition according to another preferred embodiment of the present invention, (a) polyolefin resin, polyamide resin, polybutylene terephthalate resin, acrylonitrile butadiene styrene copolymer, polycarbonate One or more thermally conductive fillers selected from expanded graphite and nitrogen boride discontinuously and uniformly in one or more thermoplastic resins selected from resins, polyester resins, polyphenylene sulfide resins and thermoplastic elastomer resins. Preparing a dispersed thermally conductive composite, (b) a polyolefin resin, a polyamide resin, a polybutylene terephthalate resin, an acrylonitrile butadiene styrene copolymer, a polycarbonate resin, a polyester resin, In polyphenylene sulfide-based resins and thermoplastic elastomer resins Preparing a resin-long fiber composite having discontinuously and uniformly dispersed long fibers having a square ratio of 50 to 3000 in at least one selected thermoplastic resin, and (c) the thermally conductive composite and the resin-long fiber composite (D) melting the shaft at a temperature higher than the melting temperature of the thermoplastic resin while mixing the thermally conductive composite and the resin-long fiber composite in the cylinder of the twin screw extruder by rotating the shaft; (E) rotating the shafts of the twin screw extruder in a predetermined direction so that shear stress is applied to the melted and compressed product so that the thermally conductive filler and the long fibers are uniformly dispersed in the thermoplastic resin. And (f) higher shear in step (e) while heating to a temperature higher than step (e) Rotating the shaft so that a force is applied to eject the composition in a twin screw extruder; and (g) cooling and cutting to obtain a thermally conductive composite composition, wherein the thermally conductive filler is 0.1 to 100 parts by weight of the thermoplastic resin. 90 parts by weight is contained, and the long fiber is contained 0.1 to 90 parts by weight based on 100 parts by weight of the thermoplastic resin.

Method for producing a thermally conductive composite material composition according to another preferred embodiment of the present invention, (a) polyolefin resin, polyamide resin, polybutylene terephthalate resin, acrylonitrile butadiene styrene copolymer, polycarbonate One or more thermally conductive fillers selected from expanded graphite and nitrogen boride discontinuously and uniformly in one or more thermoplastic resins selected from resins, polyester resins, polyphenylene sulfide resins and thermoplastic elastomer resins. Preparing a dispersed thermally conductive composite, (b) a polyolefin resin, a polyamide resin, a polybutylene terephthalate resin, an acrylonitrile butadiene styrene copolymer, a polycarbonate resin, a polyester resin, In polyphenylene sulfide-based resins and thermoplastic elastomer resins Preparing a resin-long fiber composite having discontinuously and uniformly dispersed long fibers having a square ratio of 50 to 3000 in at least one selected thermoplastic resin, and (c) the thermally conductive composite and the resin-long fiber composite Injecting and mixing the injection molding machine, (d) injecting the composition in the injection molding machine and (e) cooling to obtain a thermally conductive composite material composition, the thermally conductive filler is based on 100 parts by weight of the thermoplastic resin 0.1 to 90 parts by weight, and the long fiber is 0.1 to 90 parts by weight based on 100 parts by weight of the thermoplastic resin.

The method of manufacturing the thermally conductive composite material composition may further include adding carbon nanotubes through a side feeder in a process of causing shear stress to be applied to the melted and compressed products, wherein the carbon nanotubes are thermoplastic. It is preferable to add 0.1-10 weight part with respect to 100 weight part of resin.

In addition, the method of manufacturing the thermally conductive composite material composition may further include adding nanoclay through a side feeder in a process of causing shear stress to be applied to the melted and compressed products, wherein the nanoclay is thermoplastic It is preferable to add 0.1-10 weight part with respect to 100 weight part of resin.

In addition, the method of manufacturing the thermally conductive composite material composition, further comprising the step of adding at least one material selected from talc and calcium carbonate through a side feeder in the course of applying a shear stress to the melted and compressed product. The at least one material selected from talc and calcium carbonate may be added in an amount of 0.1 to 10 parts by weight based on 100 parts by weight of the thermoplastic resin.

In addition, the method of manufacturing the thermally conductive composite material composition may further include adding an organic nucleating agent through a side feeder in a process of causing shear stress to be applied to the melted and compressed products, wherein the organic nucleating agent is thermoplastic. It is preferable to add 0.1-10 weight part with respect to 100 weight part of resin, and the said organic nucleating agent may contain an organic carboxylate or an organophosphate.

In addition, the manufacturing method of the thermally conductive composite material composition may further include the step of adding a rubber through the side feeder in the process of applying a shear stress to the melted and compressed product, the rubber is a thermoplastic resin 100 It is preferable to add 5-40 weight part with respect to a weight part.

The expanded graphite may be made of powder-type expanded graphite having graphite connected to each other by being separated at a temperature higher than 300 ° C. after the graphite is purified with sulfuric acid, hydrogen peroxide, and NH ₄ S ₂ O ₈ .

In addition, the expanded graphite is a graphite plate peeled off with the expanded particulate graphite having a soft particulate form formed by compacting the powdered expanded graphite may have a crystal size of 10 ~ 200nm.

The nitrogen boride may be composed of a nitrogen boride-based composite formed by hybridization of nitrogen boride and magnesium oxide (MgO), and the magnesium oxide may be 5 to 40 weight parts based on 100 parts by weight of nitrogen boride in the nitrogen-boron-based composite. It is preferable to contain a part.

The long fiber may be made of one or more long fibers selected from glass fibers, carbon fibers, and organic fibers, and the long fibers preferably have a length of 0.1-20 mm.

The step of preparing the resin-long fiber composite, polyolefin resin, polyamide resin, polybutylene terephthalate resin, acrylonitrile butadiene styrene copolymer, polycarbonate resin, polyester resin, polyphenylene Injecting at least one thermoplastic resin selected from sulfide resin and thermoplastic elastomer resin into a twin screw extruder, and rotating the shaft to mix the thermoplastic resin in the cylinder of the twin screw extruder while higher than the melting temperature of the thermoplastic resin. Melting and compressing at a temperature, rotating the shafts of the twin screw extruder in a predetermined direction so that shear stress is applied to the melted and compressed thermoplastic resin, and adding a long fiber having a square ratio of 50 to 3000 through a side feeder. Uniform in the thermoplastic resin Dispersing, discharging the resin-long fiber composite in a twin screw extruder by rotating the shaft to apply a higher shear stress in the dispersing step while heating to a higher temperature than the dispersing step, and cooling and cutting the resin It may include the step of obtaining a long fiber composite material, the long fiber is preferably added 0.1 to 90 parts by weight based on 100 parts by weight of a thermoplastic resin.

In the preparing of the resin-long fiber composite, the method may further include adding carbon nanotubes through a side feeder in a process of causing shear stress to be applied to the melted and compressed products. It is preferable to add 0.1-10 weight part of tubes with respect to 100 weight part of thermoplastic resins.

In the manufacturing of the resin-long fiber composite, the method may further include adding nanoclay through a side feeder in a process of causing shear stress to be applied to the melted and compressed products, in which case the nano It is preferable to add 0.1-10 weight part of clays with respect to 100 weight part of thermoplastic resins.

The method may further include adding at least one material selected from talc and calcium carbonate through a side feeder in a process of causing shear stress to be applied to the melted and compressed products in the manufacturing of the resin-long fiber composite. In this case, the at least one material selected from talc and calcium carbonate is preferably added in an amount of 0.1 to 10 parts by weight based on 100 parts by weight of the thermoplastic resin.

In the manufacturing of the resin-long fiber composite, the method may further include adding an organic nucleating agent through a side feeder in a process of causing shear stress to be applied to the melted and compressed products. The nucleating agent is preferably added in an amount of 0.1 to 10 parts by weight based on 100 parts by weight of the thermoplastic resin, and the organic nucleating agent may include an organic carboxylate or an organophosphate.

In the manufacturing of the resin-long fiber composite, the method may further include adding rubber through a side feeder in the process of causing shear stress to be applied to the melted and compressed products. It is preferable to add 5-40 weight part with respect to 100 weight part of thermoplastic resins.

The step of preparing the thermally conductive composite, polyolefin resin, polyamide resin, polybutylene terephthalate resin, acrylonitrile butadiene styrene copolymer, polycarbonate resin, polyester resin, polyphenylene sulfide At least one thermoplastic resin selected from the group consisting of a resin and a thermoplastic elastomer resin is introduced into a twin screw extruder, and the shaft is rotated to mix the thermoplastic resin in a cylinder of the twin screw extruder at a temperature higher than the melting temperature of the thermoplastic resin. Melting and compressing, rotating the shafts of the twin screw extruder in a predetermined direction so that shear stress is applied to the molten and compressed thermoplastic resin, and at least one thermal conductivity selected from expanded graphite and nitrogen boride Filler Side Feeder Dispersing it uniformly in the thermoplastic resin, and rotating the shaft to apply a higher shear stress in the dispersing step while heating to a higher temperature than the dispersing step, thereby discharging the thermally conductive composite material from the twin screw extruder. It may include the step and cooling and cutting to obtain a thermally conductive composite, the thermally conductive filler is preferably added 0.1 to 90 parts by weight based on 100 parts by weight of the thermoplastic resin.

In the manufacturing of the thermally conductive composite, the method may further include adding carbon nanotubes through a side feeder in a process of causing shear stress to be applied to the melted and compressed products, in which case the carbon nanotubes may be It is preferable to add 0.1-10 weight part with respect to 100 weight part of thermoplastic resins.

In the manufacturing of the thermally conductive composite, the method may further include adding nanoclay through a side feeder in a process of causing shear stress to be applied to the melted and compressed products, in which case the nanoclay It is preferable to add 0.1-10 weight part with respect to 100 weight part of thermoplastic resins.

The method may further include adding one or more materials selected from talc and calcium carbonate through a side feeder in a process of causing shear stress to be applied to the molten and compressed products in the manufacturing of the thermally conductive composite. In this case, the at least one material selected from talc and calcium carbonate is preferably added in an amount of 0.1 to 10 parts by weight based on 100 parts by weight of the thermoplastic resin.

In the manufacturing of the thermally conductive composite, the method may further include adding an organic nucleating agent through a side feeder in a process of causing shear stress to be applied to the melted and compressed products, in which case the organic nucleating agent It is preferable to add 0.1-10 weight part with respect to 100 weight part of thermoplastic resins, and the said organic nucleating agent may contain an organic carboxylate or an organophosphate.

In the manufacturing of the thermally conductive composite, the method may further include adding rubber through a side feeder in a process of causing shear stress to be applied to the melted and compressed products, in which case the rubber may be a thermoplastic resin. It is preferable to add 5-40 weight part with respect to 100 weight part.

Hereinafter, a method for manufacturing a thermoplastic composite composition using a continuous twin screw extruder or an injection machine presented in Korean Patent Application No. 10-2008-0071047 filed by the applicant of the present invention is more specifically. Explain. The twin-screw extruder is designed with a screw design to provide uniform melting and mixing of the compound and obtain good dispersibility. The twin screw extruder is designed to work with compound shear (high shear in the melt and compression zone and low shear in the dispersion zone). The injection machine may use an injection machine generally known in the art.

Twin screw extruder used to prepare a thermoplastic composite composition according to a preferred embodiment of the present invention, the main feeder (110) for inputting the primary raw material (main feeder) 110, and two shafts 120 rotatably installed And a cylinder 130 surrounding the two shafts 120, drive means 140a, 140b, and 140c for rotating the shafts 120, and heating means 150 for heating the inside of the cylinder 130. And a secondary raw material in a composition in which a control means (not shown) for controlling the heating temperature of the heating means 150, a discharge die 160 for discharging the composition, and a raw material in which the melted and kneaded raw material is dispersed are dispersed. It includes a side feeder 170 for injecting in a feeding (side feeding) method.

In order to prepare a thermoplastic composite composition according to a preferred embodiment of the present invention, the content of the thermoplastic resin, the thermally conductive composite or the resin-long fiber composite is selected in a desired composition, and these raw materials are selected from the mains of the continuous twin screw exturder. The discharged composition is introduced into the feeder 110, melt-compressed, low shear stress is applied and dispersed, and the dispersed composition is discharged into a water bath. And quenched and cut to obtain a thermoplastic composite composition in pellet form.

The thermoplastic resin is a polyolefin resin, polyamide resin, polybutylene terephthalate resin, acrylonitrile butadiene styrene copolymer, polycarbonate resin, polyester resin, polyphenylene sulfide resin and thermoplastic elastomer resin It may be one or more resins selected.

The thermally conductive composite material is a polyolefin resin, polyamide resin, polybutylene terephthalate resin, acrylonitrile butadiene styrene copolymer, polycarbonate resin, polyester resin, polyphenylene sulfide resin and thermoplastic elastomer resin It is a composite material in which at least one thermally conductive filler selected from expanded graphite and nitrogen boride is discontinuously and uniformly dispersed in at least one thermoplastic resin selected from the group.

The resin-long fiber composite material may be polyolefin resin, polyamide resin, polybutylene terephthalate resin, acrylonitrile butadiene styrene copolymer, polycarbonate resin, polyester resin, polyphenylene sulfide resin and thermoplastic It is a composite material in which long fibers having a square ratio of 50 to 3000 are discontinuously and uniformly dispersed in at least one thermoplastic resin selected from elastomer resins.

Hereinafter, a method of manufacturing a thermoplastic composite composition will be described in more detail with reference to the twin screw extruder.

The thermoplastic, thermally conductive composite or resin-long fiber composite is introduced into the main feeder 110 of the twin screw extruder in accordance with the desired composition.

The thermoplastic resin or other raw material is mixed, melted and compressed in the melting and compression zone Z1 of the twin screw extruder. The raw material including the thermoplastic resin introduced through the main feeder 110 is gradually increased in temperature and begins to melt. When introduced through the main feeder 110, the thermoplastic resin may start to melt and there may be two phases of the solid resin and the molten liquid resin. When the thermoplastic resin passes through the melting and compression zone Z1, the thermoplastic resin is completely melted. The temperature of the melting and compressing region is maintained by the heating means at 200 to 310 캜 depending on the section. At this time, the two shafts 120 driven by the motor rotate clockwise, and the distance between the two shafts is about 1 to 10 cm. The shaft 120 of the molten and compressed region Z1 is provided in the form of a spiral screw for feeding the raw material injected through the main feeder 110 into the dispersion region Z2 while mixing and compressing the raw material. The helical angle of the spiral screw is, for example, about 30 degrees, and the distance between the thread of the helical screw and the cylinder 130 is about 1/60 of the diameter of the shaft. The pitch of the helical screw is, Do. The ratio of the length of the helical screw to the diameter of the helical screw in the melting and compression zone Z1 is, for example, 30 or so.

Rotating the shafts 120 of the twin screw extruder in a clockwise direction causes the melt of the raw material melted and compressed in the cylinder 130 to have a lower compression and shear stress in the dispersed zone Z2 than in the molten and compressed zone Z1 . The dispersion zone Z2 is an area in which the melt passing through the melted and compressed zone Z1 or the kneaded zone Z4 is sufficiently kneaded while flowing at a constant temperature and pressure to flow into the discharge zone Z3.

In this dispersion zone, the shafts of the twin screw extruder are rotated in a predetermined direction so that shear stress is applied to the molten and compressed thermoplastic resin, and thermally conductive fillers, long fibers, carbon nanotubes, nanoclays, talc, organic nucleating agents, rubber, etc. Silver is added through the side feeder to uniformly disperse in the thermoplastic resin. At this time, the dispersion region Z2 of the twin screw extruder is set to a temperature of 210 to 300 ℃ according to the section. The dispersed zone Z2 comprises a compression part C1 tapered in the upward direction and a flat shear part C2 formed adjacent to the upwardly tapered compression part, And has a shaft 120 structure including a tapered release portion C3. The taper angle a1 of the upwardly tapered compression portion is, for example, about 20 degrees. The taper angle a2 of the downwardly tapered compression section is, for example, about -20 °. The distance between the cylinder 130 and the shaft 120 is about 1/20 to 1/60 of the diameter of the shaft and the distance between the shaft forming the front end of the straight and the cylinder 130 is 1/40 to 1/4 of the diameter of the shaft. 1/60. The ratio of the length of the shaft 120 to the diameter of the shaft 120 in the dispersion region Z2 is, for example, about 40.

In the discharge zone Z3, the composition is discharged to the discharge die 160 by a twin screw extruder while heating to a temperature of 240 to 310 ° C. which is higher than the temperature in the dispersion zone Z2. The discharge zone Z3 is in the form of a spiral screw to supply the discharge die 160 while compressing the composition dispersed in the dispersion zone Z2, and a higher shear stress is applied than in the dispersion zone Z2. Will be. The composition dispersed in the dispersion zone Z2 is supplied to the discharge die 160 while being compressed by the shaft 120 in the form of a spiral screw. The helix angle of the helical screw is, for example, about -30 °, the spacing between the thread of the helical screw and the cylinder 130 is, for example, about 1/60 of the shaft diameter, and the pitch of the helical screw is, for example, about 5 cm. It is constant. The ratio of the length of the spiral screw to the diameter of the spiral screw in the discharge region Z3 is, for example, about 30 degrees. The composition discharged from the discharge die 160 is cooled and cut to obtain a thermoplastic composite composition in a pellet form.

Hereinafter, the experimental examples according to the present invention will be more specifically shown, and the present invention is not limited to the following experimental examples.

Thermoplastic resin and Thermal conductivity filler  selection

The manufacture of thermally conductive composite materials through the selection of thermally conductive fillers requires the selection of fillers that exhibit high thermal conductivity and the development of processes to maximize dispersion technology. In particular, the surface modification of the thermally conductive filler is a very important factor for the optimization of dispersion and complexation with the resin.

There are many difficulties in the selection of the resin and the thermally conductive filler in the production of the thermally conductive composite material composition having high thermal conductivity. The thermally conductive composite material composition is not simply to increase the content of the thermally conductive filler to improve only the thermal conductivity. That is, since the mechanical and electrical properties, processability, and price competitiveness of the applied parts in addition to the thermal conductivity characteristics are required, the filler content for maximizing the thermal conductivity characteristics cannot be increased.

On the other hand, the thermal conductivity of the thermally conductive composite material composition can be predicted through the thermal conductivity of each of the applied resin and the filler, and when combined with the difference between the thermal conductivity of the resin and the thermal conductivity of the filler, optimization of thermal conductivity properties and contents can be achieved. .

Thermoplastic resin selection and Thermal conductivity filler  selection

The matrix of the thermally conductive composite composition is selected from polypropylene and its composites, polyamide 6, polyamide 66 or its composites, polybutylene terephthalate and its composites, ABS, and the like. The materials were selected in consideration of the characteristics of both systems. In addition, the resin and thermally conductive fillers were selected to ensure continuous processability and injection moldability.

Table 1 below shows specific gravity and flow characteristics of the thermoplastic resin.

Polypropylene (PP) Polyamide 6 (PA6) Polybutylene Terephthalate (PBT) Density (g / cm3) 0.90 1.13 1.31 MFI (g / 10min) 90 63 ＞ 100 Sulfuric acid (RV) - 2.80 - Spiral flow number (cm) ＞ 120 > 60 > 60 Melting point (℃) 162 220 226

Table 2 below shows the basic characteristics of the thermally conductive filler.

black smoke BN MgO Alumina
(alumina) Density (g / cm3) 1.3 to 1.95 2.3 3.6 3.9 Thermal conductivity
(W / mK) 25 to 470 10 to 200 40 10-30 Modulus of Elasticity (GPa) 34 52 - 350 Electric resistance (Ω / □) 5 × 10 ^-6 to 30 × 10 ^-6 ＞ 10 ¹⁴ ＞ 10 ¹⁴ ＞ 10 ¹⁴ shape Plate Plate rectangle rectangle

As the insulating thermally conductive filler, a filler having excellent crystallinity is used in the manufacture of the thermally conductive composite material. In the manufacturing experiment of the thermally conductive composite material composition, four kinds of boron nitride (hereinafter referred to as 'BN') having different particle sizes from Changsung are selected, and BN / MgO hybrid (hereinafter referred to as 'BG') among BN. ) Fillers were selected and compared.

Table 3 summarizes the apparent specific gravity, surface area, and particle size of BN used in this experiment.

KBG10
(BG10) KBN20
(BN20) KBN10
(BN10) KBN5
(BN5) KBN3N
(BN3) Bulk density
bulk density (g / cm 3) 0.68 0.46 0.24 0.19 0.13 BET (㎡ / g) 6 to 8 3 to 5 5 to 6 10 to 12 25 to 35 Particle Size D50 (㎛) 6.80 16.6 7.80 5.49 2.75

Graphite in the carbon-based thermally conductive filler is the main material for making the thermally conductive composite composition. Graphite suggests a phonon collision mechanism and transfers heat in a different path than the percolation mechanism that occurs in metallic materials. In addition, due to the characteristic shape structure of the graphite, it is possible to produce a thermally conductive composite composition which is advantageous in abrasion and the like while achieving the desired thermal conductivity in a relatively small amount.

In the present invention, expanded graphite called nanographite (hereinafter referred to as 'e-graphite') was selected. e-graphite is a thermally conductive filler suitable as a carbon-based model material because of its excellent thermal conductivity and electrical conductivity, and its high thermal conductivity and particle shape that can provide an efficient heat transfer path. Table 4 summarizes the types and basic characteristics of graphite of Timcal selected in this experiment.

Powder type e-graphite (BNB90) Particle type e-graphite (C-therm) General Graphite (SFG150) Bulk Density (g / cm 3) 0.03 0.19 0.40 BET (℃ / g) 28.4 25 2.5 Oil absorption (ml / 100g) 150 - 48 Crystalline size-C axis (nm) 35 35 ＞ 200 Particle Size D50 (㎛) 85.2 - 180

e-graphite has excellent thermal conductivity compared to general graphite or carbon nanofibers due to its high square ratio. In addition, in the case of e-graphite, it is connected to the surrounding graphite plate during the exfoliation manufacturing process of graphite and has a heat transfer path. Therefore, it is determined that the same thermal conductivity can be exhibited in a smaller amount than that of ordinary graphite.

Powder-type e-graphite (Timcal BNB90, expanded graphite powder; hereinafter referred to as 'EGP') is a graphite that has been refined with sulfuric acid, hydrogen peroxide and NH ₄ S ₂ O ₈ and then stripped at 300 ℃ or higher. Difficult to put into a compound extruder. Meanwhile, particulate e-graphite (Timcal's C-therm, exapnded graphite granule; EGG), made from soft particles by gently compressing EGP, has a crystal size of 35 nm and an apparent specific gravity of 0.15 g / cm. ³ , it is more than 3 times easier to insert than EGP. In this experiment, EGG was selected as a carbon-based material, and compared with general graphite (SFG150 manufactured by Timcal (hereinafter referred to as 'SG')).

Evaluation method of heat conduction

Thermal conductivity of the thermally conductive composite composition, the thermally conductive composite or the resin-long fiber composite may be determined by the hot wire method (Test Method-1; TM-1), the Laser-Flash method, or Test Method-2; TM-2) and MTPS method (Modified Transient Plane Source Method, Test Method-3; TM-3) were evaluated by three methods.

In order to analyze the anisotropy of the thermal conductivity according to the orientation of the thermally conductive filler, the thermal conductivity in the in-plane (hereinafter referred to as 'in-plane') and axial direction (hereinafter referred to as 'through-plane') Figure data were evaluated.

Hot wire method Hot wire method )

The measurement of thermal conductivity by the hot wire method has a short specimen preparation time and a relatively simple measurement method. Heat transfer of the hot wire method is mainly performed in-plane, but the heat loss in the through-plane is a complex measurement method. Test specimens used in this experiment were measured at room temperature by injection or extrusion molding 100mm × 100mm × 3mm square specimens.

[Equation 1]

In Equation 1 above, λ is thermal conductivity (W / m · K), q is heat generated per unit length (W / m), t ₁ and t ₂ are measurement time (sec), and T ₁ and T ₂ are It is the temperature (K) at t ₁ and t ₂ .

laser Laser Flash Method

In the laser flash method, the surface of a flat sample (sample) kept at a constant temperature is pulse-heated and thermally diffused (one-dimensional) from the sample surface heated up at an instant, so that the entire sample becomes a uniform temperature. The rate of temperature change on the surface of the sample is proportional to the rate of thermal diffusion and inversely proportional to the square of the sample thickness.

The factor influencing the measurement of the laser flash method may be an error factor for the sample because the sample used is small. It has been reported that the effective thermal conductivity obtained by measuring a sample having a thickness close to the particle diameter is different from the measured value when using a thick sample. The thermal conductivity of the composite material filled with diamond particles of various particle diameters in a polyimide by making the sample thickness constant (about 100 μm) was measured. As the particle diameter increases, the thermal diffusion rate increases.

In this experiment, 100 mm × 100 mm × 2 mm square specimens were injected, and in-plane thermal conductivity was measured by preparing 1-inch disk specimens and through-plane (0.5-inch) disk specimens. . The thermal diffusivity (α) was measured, and the thermal conductivity was calculated by multiplying each measured density and heat capacity value.

&Quot; (2) "

In Equation 2 above, V = T / _Tm , ω = π ² αt / L ² , where α is the thermal diffusivity (m ² / s), T is the instantaneous temperature rise behind the specimen, and T _m is the maximum Temperature rise.

MTPS method

In the MTPS method, thermal conductivity can be evaluated in a short time because the heat reflection sensor at the interface in one direction provides the sample with a momentary and constant heat source and then measures the thermal conductivity using a mathematical calculation model. In this experiment, a TCi model manufactured by C-therm Technology Inc. was used to evaluate 100 mm × 100 mm × 3 mm square specimens.

Thermal conductivity  As composite Graphite Thermal conductivity  Composite manufacturing

High strength lightweight thermally conductive composites for battery packages were prepared using carbon-based e-graphite and polypropylene (PP), polyamide 6 (PA6) and polybutylene terephthalate (PBT) as defined in Table 1. First, the thermal conductivity of the PBT / EGP thermally conductive composite was evaluated by compounding PBT with EGP (BNB90), which is powdered e-graphite.Then, PA6 / EGG thermally conductive composites were prepared. Then, polypropylene (PP) was composited with general graphite SG (SFG150) or e-graphite EGG for comparative evaluation.

The thermally conductive composites prepared were evaluated for thermal conductivity of various methods by injection specimens unless otherwise specified, and the mechanical properties of the composites were confirmed according to the methods defined in Table 5 below.

Properties unit How to measure Flexural strength
Flexural modulus MPa According to ASTM D790, measured at a test speed of FIG. 23 ± 2 ° C., relative humidity 50% and atmospheric pressure, 3-point bend jig, cross head speed 5 mm / min. IZOD
Impact strength J / m According to ASTM D256, the energy at break of a specimen divided by the unit thickness corresponds to the impact strength. Impact strength was measured using a specimen having a thickness of 1/8 inch, measured at least five times as an average value, was measured by the Izod notch method at room temperature. Heat distortion temperature
(HDT) ℃ According to ASTM D648, the temperature was measured when the deformation of the specimen reached 0.254 mm while raising the ambient fluid temperature at a rate of 2 ° C./min under 4.5 MPa pressure. In the case of PP LGF, 0.45 MPa and 4.5 MPa were applied, and the measurement was performed at 4.5 MPa unless otherwise specified. Hardness Shore d Shore D was measured on plate specimens using an Instron hardness tester according to ASTM D2240.

PBT Of EGP Thermal conductivity  Manufacture of Composites

A PBT / EGP thermally conductive composite having a thermal conductivity of 4.45 W / m · K was prepared using the composition of Table 6. In the TEK-45 twin screw extruder, polybutylene terephthalate (hereafter referred to as 'PBT') and powdered e-graphite (expanded graphite powder) (EGP) were attempted to be combined, but the low apparent specific gravity (bulk density, 0.03) of EGP was attempted. g / cm ³ ), making it difficult to feed by the side feeder, and a small 20mm twin screw extruder was used as a next best solution. PBT and EGP were added together to the main feeder, and the filling rate was adjusted to 0 to 60% by weight. In Table 6, the heat stabilizer was added 0.2 parts by weight based on 100 parts by weight of the total content of PBT and EGP.

Code number EX-01 EX-02 EX-03 EX-04 EX-05 EX-06 EX-07 PBT 90 80 70 60 50 45 40 EGP 10 20 30 40 50 55 60 Heat stabilizer 0.2 0.2 0.2 0.2 0.2 0.2 0.2

The thermally conductive composite was prepared at 235 ~ 255 ℃, the discharge amount was adjusted to 1kg / h. In order to prevent separation of PBT and graphite, PBT was freeze-pulverized into powder and then mixed with graphite and added. As the content of graphite increases, the melt strength of the thermally conductive composite discharged from the die decreases and the hardness of the solidified string increases, making pelleting increasingly difficult, eventually breaking out of the shape of the pellet, making it difficult for further continuous processing.

100 mm x 100 mm x 2 mm specimens were prepared at a temperature of 230 ° C. by compression molding using a small amount of the thermally conductive composite sample taken.

The thermal conductivity of the specimen was confirmed by the thermal wire method (TM1 method), and as a result, as shown in Table 7 and FIG. 8, the thermal conductivity increased with the increase of e-graphite, and the graphite content of the thermally conductive composite was 40% by weight. The thermal conductivity is rapidly increasing. When the graphite content of the thermally conductive composite reached 60% by weight, the thermal conductivity increased to 4.5W / m · K.

Code number EX-01 EX-02 EX-03 EX-04 EX-05 EX-06 EX-07 Thermal conductivity
(TM-1 in-plane) 0.47 0.71 0.89 1.98 2.83 3.02 4.49

FIG. 8 is a graph showing the effect of the change in thermal conductivity and the addition of CNTs according to the graphite content of the PBT / EGP thermally conductive composite.

PA6 Of EGG Thermal conductivity  Manufacture of Composites

PA6 / EGG thermally conductive composites were prepared. In order to solve the feeding problem of powder type e-graphite, high-flow polyamide 6 (PA6) is added to the main feeder, and fine particle type e-graphite (EGG), which is about 6 times higher than EGP, is added by side feeding method. PA6 / EGG thermally conductive composites were prepared.

The method of introducing thermally conductive fillers or long fibers by side feeding is a very important process in mass commercial compounding processes. In particular, when glass fiber, relatively soft graphite, or BN is added to the main feeder along with the resin, the filler breaks down with the solid resin through the first melting and kneading block, causing severe damage to the filler. Or aggregates. This results in smaller square ratios or larger thermally conductive fillers. To prevent this, the resin is melted and then the thermally conductive filler or long fiber is introduced from the side feeder of the twin screw extruder to obtain excellent physical properties while increasing the dispersibility of the filler or long fiber, so that the side feeder located at the bottom of the twin screw extruder It is advantageous to use.

In the PA6 / EGG thermally conductive composite composition of Table 8, high fluid PA6, rubber of impact modifier (rubber), MWNT, and heat stabilizer (antioxidant) were added together. In Table 8, MWNT was added 1 part by weight based on 100 parts by weight of PA6, EGG and 100 parts by weight of rubber, and the heat stabilizer was added 0.2 parts by weight based on 100 parts by weight of PA6, EGG and 100 parts by weight of rubber.

Code number EX-8 EX-9 EX-10 PA6 60 50 40 EGG 20 30 40 Rubber 20 20 20 MWNT One One One Heat stabilizer 0.2 0.2 0.2

The thermally conductive composite was prepared at 265 to 290 ° C., and e-graphite was added to 0 to 40 wt% through a side feeder. Thermally conductive composites were made with a TEK-45 twin screw extruder.

The thermal diffusivity was measured by the laser flash method (TM-2 method) using the extruded 100 mm x 100 mm x 3 mm square specimens. After measuring the density and heat capacity (Cp) of the specimen at room temperature, the thermal conductivity was calculated.

Table 9 shows the thermal conductivity evaluation results by the laser flash method of the PA6 / EGG thermally conductive composite. 9 is a graph of the in-plane thermal conductivity by the laser flash method according to the graphite content of the PA6 / EGG thermal conductive composite, the thermal conductivity of the in-plane measured in the injection direction is significantly improved as the content of e-graphite increases And, it was able to produce a thermally conductive composite of 9.3 W / mK when the EGG 40% by weight.

Code number EX-8 EX-9 EX-10 importance 1.2285 1.2289 1.3282 Thermal conductivity
(W / mK) (TM-2)
In-plane 4.08 7.36 9.33 (TM-2)
Through-plane 1.57 2.50 2.22

10 is a through-plane thermal conductivity measurement results by the laser flash method according to the graphite content of the PA6 / EGG thermal conductive composite material. Through-plane in the thickness direction of the specimen was evaluated to be about 1/3 to 1/5 of the in-plane thermal conductivity.

In order to improve injection molding and compound workability, the thermally conductive composite was designed by increasing the content of impact modifier to 30% by weight. Table 10 summarizes the composition and physical property evaluation of PA6 / EGG. In Table 10 below, the heat stabilizer added 0.2 parts by weight based on 100 parts by weight of PA6, EGG and 100 parts by weight of rubber, and the nucleating agent added 0.5 parts by weight, based on 100 parts by weight of PA6, EGG and 100 parts by weight of rubber. The processability was somewhat improved than the composition of the rubber (20% by weight) of the rubber (rubber), but still a lot of string failure (string failure) caused a lot of difficulties in the pelletization process.

The nucleating agent may be an organic nucleating agent, an inorganic nucleating agent or a nanonuclear agent. The organic nucleating agent may include an organic dicarboxylic acid salt such as Millen's Hyperform 68L, an organic phosphate salt such as Na-21, and the like. It is possible to use organic nucleating agents. In addition, it is also possible to prescribe a mineral nucleating agent such as calcium carbonate and talc as the inorganic nucleating agent. And nanoclay is very effective as the nano nucleating agent, the addition of MWNT, nano silica, nano alumina can bring a similar effect. The nucleating agent used in this experiment was Cloisite 15A from Southern Clay Products of the United States, a nanoclay designed to be most dispersed in PP. Nanoclays are well suited for the high-charge thermally conductive composites of the present invention because they can act as nucleating agents as well as process aids to aid injection molding.

The thermal conductivity of the PA / EGG thermally conductive composites of Table 10 increases with the content of e-graphite. 11 is a graph comparing the difference between the rubber content and the thermal conductivity evaluation method of the PA6 / EGG thermal conductive composite material. The thermal conductivity by the hot wire method was 1.264 W / m · K, which was evaluated to be relatively lower than the measured value of the laser flash method of Table 9, and the results of PBT / EGP of Table 7 (1.98 W / m at 40 wt% of EGP). It was estimated to be somewhat lower compared to K). The result of such low thermal conductivity is that the composition of Table 9 contains 1.0 parts by weight of MWNT, it is determined by the effect of CNT.

Code number EX-11 EX-12 EX-13

Furtherance

PA6 50 40 30 EGG 20 30 40 Rubber 30 30 30 Heat stabilizer 0.2 0.2 0.2 Nucleating agent 0.5 0.5 0.5


Properties



importance 1.149 1.202 1.254 Flexural modulus (MPa) 1,629 2,139 2,838 IZOD impact strength (J / m) 33 28 28 MFI 2.3 0.9 0.3 Spiral flow 85 67 56 Surface resistance (Ω / □) 2 × 10 ⁸ 6 × 10 ⁶ 5 × 10 ⁶ Thermal conductivity
(W / mK) TM-1
In-plane 0.705 1.006 1.264

PP /black smoke Thermal conductivity  Composite manufacturing

Based on the experimental results of PBT and PA6 described above, the thermal properties were evaluated using the three thermal conductivity measurement methods defined above while comparing the physical properties by mixing general graphite and e-graphite in the PP resin.

By ordinary graphite Thermal conductivity  Manufacture of Composites

General graphite was introduced into a twin screw extruder to prepare a PP / SG thermally conductive composite. Timcal's SG (SFG150) is natural graphite and has a crystal size of 200 nm or more, more than 7 times larger than e-graphite, and a particle size of 85 μm, which is more than twice the size of e-graphite. In the TEK-45 twin screw extruder, PP was added using a main feeder, and normal graphite was added using a side feeder. Thermally conductive composites were prepared at 215-230 ° C. As shown in Table 11, a certain amount of stabilizer and nucleating agent was added while controlling the composition ratio of PP and SG. The dose of SG was adjusted to 0-50 weight%.

Table 11 shows the composition of the PP / SG thermally conductive composites. In Table 11, an antioxidant was added 0.2 parts by weight based on 100 parts by weight of PP and SFG150, and a nucleating agent was added 0.5 parts by weight based on 100 parts by weight of PP and SFG150.

The nucleating agent may be an organic nucleating agent, an inorganic nucleating agent or a nanonuclear agent. The organic nucleating agent may include an organic dicarboxylic acid salt such as Millen's Hyperform 68L, an organic phosphate salt such as Na-21, and the like. It is possible to use organic nucleating agents. In addition, it is also possible to prescribe a mineral nucleating agent such as calcium carbonate and talc as the inorganic nucleating agent. And nanoclay is very effective as the nano nucleating agent, the addition of MWNT, nano silica, nano alumina can bring a similar effect. The nucleating agent used in this experiment was Cloisite 15A from Southern Clay Products of the United States, a nanoclay designed to be most dispersed in PP. Nanoclays are well suited for the high-fill resin-fiber composites of the present invention because they can act as nucleating agents as well as process aids to aid injection molding.

Code number EX-14 EX-15 EX-16 EX-17 EX-18 EX-19 PP 100 100 80 70 60 50 SFG150 0 0 20 30 40 50 Heat stabilizer 0.2 0.2 0.2 0.2 0.2 0.2 Nucleating agent 0 0.5 0.5 0.5 0.5 0.5

Table 12 shows the physical properties of the PP / SG thermally conductive composite. In the absence of a thermally conductive filler as a nucleating agent, the thermal conductivity of PP was improved by about 28%, and the thermal conductivity of PP / SG thermally conductive composites was improved by increasing the amount of graphite according to the thermal wire method (TM1). It is 3.89 W / mK level at 50 wt% of the charge. 12 is a graph showing a change in impact strength and flexural modulus according to the SG content of the PP / SG thermal conductive composite. The flexural modulus improved with increasing the filling rate of graphite, but lost ductility due to the drop in impact strength. Melt flowability gradually decreased with increasing filling rate, resulting in an MFI of 21 at a filling rate of 50% by weight. When evaluating flowability as MFI, MFI is a function of graphite particle size, and as the size becomes smaller, the MFI decreases dramatically. Since the particle size of SG graphite is larger than that of e-graphite, the MFI of PP / SG thermally conductive composites tends to decrease slowly.

Code number EX-14 EX-15 EX-16 EX-17 EX-18 EX-19 importance 0.91 0.92 1.012 1.088 1.196 1.282 Hardness (D) 65 66 67 69 70 74 Flexural modulus
(MPa) 1,500 1,550 2,676 4,254 5,478 8,029 Impact strength (J / m) 60 50 30 29 24 23 MFI 58 55 50 43 36 21 Thermal Conductivity (W / mK)
(TM1 in-plane) 0.25 0.32 0.63 1.10 1.80 3.89

e-graphite Thermal conductivity  Manufacture of Composites

PP / EGG thermally conductive composites were prepared using e-graphite. The compound was carried out under the same conditions as in the case of ordinary graphite. As shown in Table 13, the composition ratio of EGG was adjusted to 20 to 40% by weight, and the stabilizer and the nucleating agent were added in the same manner as the composition of general graphite.

Table 13 shows the composition of the PP / EGG thermally conductive composites. In Table 13, an antioxidant was added 0.2 parts by weight based on 100 parts by weight of PP and EGG, and a nucleating agent was added 0.5 parts by weight, based on 100 parts by weight of PP and EGG. The nucleating agent used in this experiment was Cloisite 15A from Southern Clay Products of the United States, a nanoclay designed to be most dispersed in PP. Nanoclays are well suited for the high-charge thermally conductive composites of the present invention because they can act as nucleating agents as well as process aids to aid injection molding.

In the case of PP used in this experiment, the crystallization temperature was increased by about 9 ° C and the crystallinity was increased by 4% by the evaluation of thermogravimetric analysis by adding a small amount of Cloisite 15A.

Code number EX-20 EX-21 EX-22 EX-23 PP 100 80 70 60 EGG 0 20 30 40 Heat stabilizer 0.2 0.2 0.2 0.2 Nucleating agent 0.5 0.5 0.5 0.5

A 25% by weight composite of e-graphite forms a heat transfer path past the percolation concentration. At the concentration of percolation, the steep increase of the thermally conductive composite properties, that is, the thermal conductivity and the flexural modulus, are expected to increase. In the following physical property evaluation results, it was observed that the heat transfer path was well formed through the percolation concentration by the 30% by weight composite of e-graphite.

Table 14 evaluates the physical properties of the PP / EGG thermally conductive composite. The thermal conductivity of the PP / EGG thermally conductive composites was evaluated to be 3.786 W / m · K at 40 wt% filling rate according to the hot wire method. FIG. 13 shows the thermal conductivity change of the thermal wire method according to the graphite content of the PP / SG thermally conductive composite and the PP / EGG thermally conductive composite. At 20 to 40 wt% filling rate, the thermal conductivity was twice as good as that of ordinary graphite.

Code number EX-20 EX-21 EX-22 EX-23 density 0.91 1.01 1.09 1.20 Flexural modulus (MPa) 1,550 2,996 5,879 8,829 IZOD impact strength (J / m) 50 19 24 24 Heat deformation temperature (캜) - 72 83 92 MFI 55 8 0.4 0.1 Spiral Flow (cm) 120 91 67 55 Surface resistance (Ω / □) > 10 ¹³ 2 × 10 ⁵ 5 × 10 ⁴ 1 × 10 ³ Thermoelectric
dodo
(W / mK) TM-1
(In-plane) 0.32 1.166 1.846 3.736 TM-3
(Thru-plane) 0.27 0.553 0.685 1.166

At 30 wt. The effect of the particle size of the e-graphite seems to have resulted in a deterioration of flowability beyond the percolation concentration.

14 is a graph showing the impact strength and flexural modulus change according to the e-graphite content of the PP / EGG thermally conductive composite. As the filling rate of e-graphite increased, the flexural modulus increased more steeply than ordinary graphite, while the impact strength lost most of the ductility of PP, and dropped from 80 J / m of PP resin to 24 J / m at 40 wt%. Such a drop in impact strength will be a problem in the actual componentization process, and a composite design is needed to solve the drop in impact strength.

BN system Thermal conductivity  Composite manufacturing

Thermally conductive composites were prepared using the insulating fillers BN, BG, polypropylene (PP), polyamide 6 (PA6), and polybutylene terephthalate (PBT).

In a similar manner to the development of graphite-based thermally conductive composites, thermally conductive composites of insulating fillers were prepared using PBT and BG, and BN and BG were composited with PA6 resin to prepare thermally conductive composites. Thermally conductive composites were prepared while comparing BN.

BN-based thermally conductive composites were prepared under the same compound conditions as those of the thermally conductive composites using graphite, and the types of resins were also manufactured in the same grade. In the filling process of the thermally conductive fillers, the fillers were easily injected into the resin because the melt strength was not significantly lower than that of the graphite, and the resin was added to the main feeder and the BN filler using the side feeder.

PBT Of BG Thermal conductivity  Composite manufacturing

PBT / BG thermally conductive composites were prepared. Table 15 shows the composition of the PBT / BG10 thermally conductive composites. BG10 means Changsung's BN / MgO hybrid (BG) product.

PBT and BG were made of a thermally conductive composite using a small twin screw extruder. The polymer and filler were put together in the main feeder, the filling rate was 0 to 60% by weight, the discharge amount was adjusted to 1kg / h. In order to prevent the separation of the PBT and the powder filler, the PBT was freeze-pulverized, mixed well with BG, and then added. In addition, 2.5 parts by weight of MWNT (Nanocyl NC7000) was added to the BG composition of 10 to 40% by weight in order to determine the effect of CNT. There was no addition of other additives except adding 0.2 parts by weight of the heat stabilizer.

In Table 15, the heat stabilizer (antioxidant) was added 0.2 parts by weight based on 100 parts by weight of the total content of PBT and BG10, MWNT was added 0 parts or 2.5 parts by weight based on 100 parts by weight of the total content of PBT and BG10, EX -24, EX-25, EX-26, EX-27, EX-28, EX-29, EX-30 are without MWNT, EX-31, EX-32, EX-33, EX-34 And EX-35 is the case where MWNT is added 2.5 parts by weight based on 100 parts by weight of the total content of PBT and BG10.

Code number EX-24 EX-25 EX-26 EX-27 EX-28 EX-29 EX-30 EX-31 EX-32 EX-33 EX-34 EX-35 PBT 90 80 70 60 50 45 40 90 80 70 60 50 BG10 10 20 30 40 50 65 60 10 20 30 40 50 MWNT 0 0 0 0 0 0 0 2.5 2.5 2.5 2.5 2.5 Heat stabilizer 0.2 0.2 0.2 0.2 0.2 0.2 0.2 0.2 0.2 0.2 0.2 0.2

The thermal conductivity change according to the BG content of PBT / BG10 thermally conductive composites is shown. The thermal conductivity of the 2 mm thick thermally conductive composite specimens produced by the twin screw extruder was evaluated by the thermal wire method (TM1 method). The figure showed the level of 1 W / m * K.

Table 16 shows the results of thermal conductivity measurement by TM-1 method of PBT / BG10 thermally conductive composites.

Code number EX-24 EX-25 EX-26 EX-27 EX-28 EX-29 EX-30 Thermal conductivity
(In-plane) 0.27 0.32 0.49 0.59 1.04 1.07 1.20 Code number EX-31 EX-32 EX-33 EX-34 EX-35 Thermal conductivity
(In-plane) 0.44 0.47 0.59 0.74 1.07

FIG. 15 is a graph comparing the change in thermal conductivity of PBT / BG10 thermally conductive composites according to the content of BG when MWNT is not present and when MWNT is present by 2.5 parts by weight, and shows a synergistic effect of thermal conductivity due to CNT. In particular, it showed about twice the thermal conductivity improvement in specimens having a low BG filling rate (10 wt% to 20 wt% of BG).

PA6 Of BG  Preparation of Thermally Conductive Composites

PA6 / BG thermally conductive composites were prepared. PA6 / BN thermally conductive composites were prepared using high flow PA6 and BN and BG having a particle size of about 10 μm. BN used Changsung Corporation's KBN10, and a powder having an apparent specific gravity of 0.4 was added to the molten PA6 in a side feeder of a TEK-45 twin screw extruder. PA6-based thermally conductive composites were prepared using the composition of the PA6 / BN10 thermally conductive composites shown in Table 17. When BN was added to PA6 resin alone, the thread was frequently trimmed so that the continuous pellet process could not be performed. Thus, 20% by weight of impact reinforcing rubber was mixed and added through the main feeder. It was possible to increase the filling rate of the BN powder.

Table 17 shows the composition of the PA6 / BN10 thermally conductive composites. In Table 17, the heat stabilizer (antioxidant) was added 0.2 parts by weight based on 100 parts by weight of the total content of PA6, BN10 and rubber, the nucleating agent 0.5 parts by weight based on 100 parts by weight of total content of PA6, BN10 and rubber Added. The nucleating agent used in this experiment was Cloisite 93A from Southern Clay Products of the United States, a nanoclay designed to be most dispersed in PA6. Nanoclays are well suited for the high-charge thermally conductive composites of the present invention because they can act as nucleating agents as well as process aids to aid injection molding.

Code number EX-36 EX-37 EX-38 EX-39 PA6 60 50 40 30 BN10 20 30 40 50 Rubber 20 20 20 20 Heat stabilizer 0.2 0.2 0.2 0.2 Nucleating agent 0.5 0.5 0.5 0.5

Thermally conductive composites were prepared at 265 to 290 ° C, injection was made of 100 mm × 100 mm square specimens, and thermal conductivity was evaluated by three methods: hot wire method (TM1), laser flash method (TM2), and MTPS method (TM3). It was. In addition, the flexural strength and the IZDO impact strength were measured using physical specimens manufactured using ATSM standard molds.

As shown in Table 18 and FIG. 16 below, the thermal conductivity in the injection direction of the in-plane is increased as the BN content is increased, and the thermal conductivity is 1.53 W / m at a 50% by weight filling rate when evaluated by the TM-1 method. K level thermally conductive materials could be prepared. Thermal conductivity in the through-plane was about 60% by weight of in-plane for high charge (40-50% by weight) and 120% for low charge (20-30% by weight).

Code number EX-36 EX-37 EX-38 EX-39 importance 1.251 1.312 1.415 1.468 Flexural Strength (MPa) 82 81 87 93 Flexural modulus (MPa) 3,197 3,930 6,175 7,639 IZOD impact strength (J / m) 29 27 17 14 MFI 11 10 2 One Spiral Flow (cm) 55 52 36 43 Surface resistance (Ω / □) > 10 ¹³ > 10 ¹³ > 10 ¹³ > 10 ¹³ Thermoelectric
dodo
(W / mK)

TM-1
(In-plane) 0.431 0.512 1.404 1.534 TM-2
(Thru-plane) - 1.114 2.188 - TM-3
(Thru-plane) 0.578 0.725 0.937 1.032

17 is a graph showing changes in flexural modulus and impact strength according to BN content of PA6 / BN10 thermally conductive composites. The flexural modulus / impact strength balance of PA6 / BN10 thermally conductive composites was similar to that of e-graphite, and the flexural modulus was improved with increasing BN content, but the impact strength was abruptly decreased with the addition of BN. This decrease in impact strength has been repeatedly observed, which is a predictable phenomenon that occurs when a large amount of inorganic material, especially plate or spherical particles, is added. However, such a drop in impact strength (reduced from 118 J / m to 14 J / m at 50 wt% BN in the case of PA6 resin) will be a problem in the parts manufacturing process as indicated in the case of graphite.

PA6 / BG thermally conductive composites of Table 19 were prepared in the same manner as the PA6 / BN thermally conductive composites were prepared. Table 20 summarizes the mechanical and thermal conductivity measurement results of the PA6 / BG thermally conductive composite. The PA6 / BG thermally conductive composites have lower thermal conductivity than the PA6 / BN thermally conductive composites, and the difference in in-plane thermal conductivity levels is about 20-30%. Through-plane thermal conductivity levels were nearly similar.

Table 19 shows the composition of the PA6 / BG10 thermally conductive composites. In Table 19, the antioxidant was added 0.2 parts by weight based on 100 parts by weight of the total content of PA6, BG10 and rubber, and the nucleating agent was 0.5 parts by weight based on 100 parts by weight of the total content of PA6, BG10 and rubber. Added. The nucleating agent used in this experiment was Cloisite 93A from Southern Clay Products of the United States, a nanoclay designed to be most dispersed in PA6.

Code number EX-40 EX-41 EX-42 PA6 80 60 50 BG10 0 20 30 Rubber 20 20 20 Heat stabilizer 0.2 0.2 0.2 Nucleating agent 0.5 0.5 0.5

Table 20 shows the physical properties and thermal conductivity of PA6 / BG10 thermally conductive composites.

Code number EX-40 EX-41 EX-42 importance 1.050 1.289 1.649 Flexural Strength (MPa) 47 93 95 Flexural modulus (MPa) 1,302 2,822 5,741 IZOD impact strength (J / m) 800 29 20 Thermal conductivity
(W / mK) TM-1
In-plane 0.300 0.358 1.147 TM-3
Through-plane - 0.487 1.040

18 is a graph comparing the flexural modulus of PA6 / BN10 and PA6 / BG10 thermally conductive composites, and it can be seen that the mechanical properties of PA6 / BN thermally conductive composites have better reinforcing ability than PA6 / BG thermally conductive composites. This may be due to the effect of reducing the rectangular ratio of the PA6 / BG10 resulting from the mixing of the MgO sphere and the BN platelet structure.

PP Of BN Thermal conductivity  Composite manufacturing

PP / BN thermally conductive composites were prepared. Thermal conductivity was evaluated by three methods, the hot wire method, the laser flash method, and the MTPS method.

Table 21 shows the composition of the PP / BN thermally conductive composites. 3 micrometers, 5 micrometers, and 10 micrometers of 3 kinds of BNs with different particle sizes were selected, PP resin was put into the main feeder of a TEK-45 twin screw extruder, and BN was put into the side feeder. The input content was adjusted to 20 to 50% by weight and the composition ratio of PP and BN is shown in Table 21 below. In addition, 2,000 ppm of stabilizer and 5,000 ppm of nucleating agent were added. The nucleating agent used in this experiment was Cloisite 15A from Southern Clay Products of the United States, a nanoclay designed to be most dispersed in PP.

The BG filler was also compared under the same conditions, but the BG was charged up to 50% by weight.

In Table 21, the heat stabilizer (antioxidant) was added 0.2 parts by weight based on 100 parts by weight of the total content of BN or BG and PP, the nucleating agent 0.5 parts by weight based on 100 parts by weight of the total content of BN or BG and PP Part was added.

Code number EX-43 EX-44 EX-45 EX-46 EX-47 EX-48 EX-49 EX-50 PP 80 80 80 80 70 60 50 50 BN-03 20 - - - - - - - BN-05 - 20 - - - - - - BG-10 - - 20 - - - - 50 BN-10 - - - 20 30 40 50 - Heat stabilizer 0.2 0.2 0.2 0.2 0.2 0.2 0.2 0.2 Nucleating agent 0.5 0.5 0.5 0.5 0.5 0.5 0.5 0.5

Table 22 shows the properties of PP / BN thermally conductive composites. The highest level of thermal conductivity of PP / BN thermally conductive composites that can be continuously manufactured on a specific extruder is about 1.4 W / mK in in-plane by thermal wire measurement. Level. The effect of BN particle size on the thermal conductivity was not significant, and when BN3 was charged by 20% by weight, BN3 having the highest thermal conductivity was the highest, followed by BN10 having the 10 µm and BN5 having the lowest thickness at 5 µm. Is also shown. 19 is a graph showing thermal conductivity according to BN content of a PP / BN thermally conductive composite and a PP / BG thermally conductive composite.

Code number EX-43 EX-44 EX-45 EX-46 EX-47 EX-48 EX-49 EX-50 importance 1.016 1.009 1.061 1.021 1.104 1.187 1.304 1.409 Flexural Strength (MPa) 49 49 47 42 40 39 37 39 Flexural modulus (MPa) 2,876 2,658 2,122 2,024 2,728 2,819 4,949 3,774 IZOD impact strength (J / m) 29 26 25 21 21 18 18 16 Heat
I'm
Degree
Degree (W / mK) TM-1
In-plane 0.341 0.304 0.307 0.329 0.415 0.526 1.410 0.472 TM-2
Through-plane 1.036 1.227 TM-3
Through-plane 0.403 0.275 0.258 0.354 0.460 0.637 0.769 0.624

The flexural modulus also increased with increasing BN content in the mechanical properties of the PP / BN thermally conductive composites, and the impact strength decreased rapidly. In particular, the impact strength was very low, 16 to 18 J / m at 50% by weight filler. 20 is a comparison of the flexural modulus and impact strength according to the BN particle size of the PP / BN thermally conductive composite. As the BN particle size increased, the flexural modulus and impact strength decreased, but the difference was not large.

Manufacture of composite material by glass fiber reinforcement

Resin-Fiber Composite Manufacturing

In the above, a sudden drop in impact strength was observed in the thermally conductive composite properties due to graphite or BN. Among the methods for solving this problem, the method of mixing the fibers to make the resin-fiber composite is more advantageous in terms of strength or heat resistance than the method of adding a rubber component to reinforce the impact. This is because by reinforcing fiber shapes such as glass fibers (hereinafter referred to as 'GF'), carbon fibers, and organic fibers, rigidity can be improved while using a mechanism to absorb impact energy in the resin and fiber interfaces.

In this experiment, a comparative experiment of reinforcing glass fibers in PP, PA6, and PA66 resins was performed with a TEK-45 twin screw extruder, and in order to increase affinity for each resin, short glass fibers (hereinafter referred to as 'SGF'), L = 3.4 mm) was selected, and resin-fiber composites were prepared for each glass fiber content and mechanical properties were evaluated as shown in Tables 23, 24, and 25.

As expected, the flexural modulus and heat deflection temperature increased with increasing glass fiber (GF). At about 30 wt. 8000 MPa / 111J / m, PA66 10,000MPa / 114J / m, PA66 showed the best physical properties. The heat deformation temperature of the resin-fiber composite containing 50% by weight of GF was evaluated as 160 ° C for the PP-based resin-fiber composite, 206 ° C for the PA6 resin-fiber composite, and 246 ° C for the PA66-based resin-fiber composite. PA66 showed the superior heat resistance in the order of> PA6> PP.

Table 23 shows the composition and physical properties of the PP / SFG composite, a resin-fiber composite.

Code number EX-51 EX-52 EX-53 EX-54
Furtherance
PP 99.8 89.8 79.8 69.8 SGF 0 10 20 30 Heat stabilizer 0.2 0.2 0.2 0.2

Properties

Flexural Strength (MPa) 42 57 72 99 Flexural modulus (MPa) 1,457 2,098 3,553 4,348 IZOD impact strength (J / m) 42 61 60 80 importance 0.91 1.00 1.03 1.12 Heat deformation temperature (캜) 76 148 159 160

Table 24 shows the composition and physical properties of the PA6 / SGF composite, a resin-fiber composite.

Code number EX-55 EX-56 EX-57 EX-58 EX-59
Furtherance
PA6 99.8 87.8 84.8 79.8 69.8 SGF 0 12 15 20 30 Heat stabilizer 0.2 0.2 0.2 0.2 0.2

Properties

Flexural Strength (MPa) 87 135 169 173 242 Flexural modulus (MPa) 2,632 3,785 4,449 4,645 8,005 IZOD impact strength (J / m) 33 38 49 59 111 importance 1.12 1.21 1.23 1.27 1.35 Heat deformation temperature (캜) 55 180 193 204 206

Table 25 shows the composition and physical properties of the PA66 / SGF composite, a resin-fiber composite.

Code number EX-60 EX-61 EX-62 EX-63 EX-64
Furtherance
PA66 99.8 79.8 74.8 69.8 64.8 SGF 0 20 25 30 35 Heat stabilizer 0.2 0.2 0.2 0.2 0.2

Properties

Flexural Strength (MPa) 90 191 249 252 280 Flexural modulus (MPa) 2,530 6,542 7,573 8,932 10,219 IZOD impact strength (J / m) 36 42 82 90 114 importance 1.14 1.28 1.31 1.37 1.42 Heat deformation temperature (캜) 73 241 243 245 246

In relation to the GF content and the flexural modulus, 7,000 MPa can be achieved if a certain amount of short glass fiber is mixed with graphite or BN thermally conductive composites.

However, the IZOD impact strength is about 100 J / m in the PA6 and PA66 resins, and the level of the resin-fiber composite reinforced by 30 wt% or more of GF is about 100 J / m. It is difficult to achieve. In order to solve this problem, it is possible to prescribe rubber as an impact modifier, but this method will increase the price of the material due to expensive rubber, which will not only reduce the competitiveness, but also reduce the flexural strength and heat deformation temperature.

As another method to solve this problem, a PP / LGF composite was prepared by long glass fiber (LGF) to reinforce the impact strength of IZOD. First, a PP-LGF50 composite material having a LGF content of 50% by weight is manufactured by using a pultrusion process, and then, the PP resin is mixed to adjust the glass fiber content to 10 to 50% by weight, as shown in Table 26. Was evaluated.

Table 26 is a physical property according to the glass fiber (GF) content of the resin / long fiber composite PP / LGF composite.

Code number EX-65 EX-66 EX-67 EX-68 EX-69 EX-70
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PP 99.6 79.6 59.6 39.6 19.6 0 PP-LGF50 0 20 40 60 80 100 Heat stabilizer 0.2 0.2 0.2 0.2 0.2 0.2 Ultraviolet stabilizer 0.2 0.2 0.2 0.2 0.2 0.2
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Flexural Strength (MPa) 420 95 126 141 180 177 Flexural modulus (MPa) 1,456 3,045 4,217 4,999 7,117 8,615 IZOD impact strength
(J / m) 42 95 166 171 189 201 importance 0.91 0.95 1.02 1.12 1.23 1.30 Heat deformation temperature (캜) - 70 72 73 76 79

It can be seen that the balance of flexural modulus and impact strength of the LGF specimens is significantly improved compared to the PP / SGF composites. 21 is a graph comparing flexural modulus and impact strength according to SGF and LGF of GF-reinforced resin-fiber composites reinforced with PP, PA6, and PA66. Compared to PP / LGF composite and PP / SGF composite at 30% by weight of GF content, the impact strength was about 171J / m, which is about 3 times the impact strength. PP / LGF composite achieved 201J / m at 50% by weight It was.

The PA6 / LGF composites were expected to have better heat resistance than the PP / LGF composites. First, PA6-LGF50 having 50% by weight of LGF was prepared using high flow PA6, and mixed with PA6 resin to evaluate physical properties. Table 27 shows the physical properties of the PA6 / LGF composite according to the GF content of PA6-LGF50 / PA6. PA6 / LGF composites have an impact strength of 127-238J / m, which is about twice the impact improvement compared to PA6 / SGF composites. In addition, the impact is comparable to that of the PP / LGF composite, but shows a significant improvement in the heat deflection temperature. For comparison, the heat deflection temperature of PP / LGF and PA / LGF composites was measured at a pressure of 4.6 MPa.

Code number EX-71 EX-72 EX-73 EX-74
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PA6 59.6 39.6 19.6 0 PA6-LGF50 40 60 80 100 Heat stabilizer 0.2 0.2 0.2 - Ultraviolet stabilizer 0.2 0.2 0.2 - GF content (% by weight) 20 30 40 50
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Flexural Strength (MPa) 221 270 322 344 Flexural modulus (MPa) 6,309 9,005 11,404 14,439 IZOD impact strength (J / m) 127 188 206 238 importance 1.270 1.363 1.485 1.656 Heat deformation temperature (캜) 215 217 216 215 Spiral Flow (cm) 77 72 54 48 Shore D 82 83 84 85

Judging from the results of the above-mentioned LGF reinforced composites, if the LGF system is applied to the thermally conductive composite, it will be very advantageous to improve the impact. Therefore, experiments were conducted to apply the prepared PP / LGF composite material and PA6 / LGF composite material to the thermally conductive composition.

Glass fiber reinforcement Thermal conductivity Of composite composition  Produce

Resin-long fiber composites satisfying the rigidity / impact balance were prepared by the glass long fibers. In particular, securing mechanical properties by LFG solved the impact drop that has always been a problem in the properties of general GF-reinforced composites and improved thermal conductivity.

Graphite Thermal conductivity  Apply to composite

After reviewing the physical properties of the short glass fiber and the long fiber composite, the glass fiber having the most favorable balance between impact strength and rigidity was selected and mixed with the already prepared e-graphite thermally conductive composite, followed by PP / EGG / LGF. The thermal conductive composite composition was prepared and evaluated.

Table 28 shows the composition and physical properties of the PP / EGG / LFT thermally conductive composite composition. The physical properties of the specimens injected into ASTM standard molds by adjusting the LGF content to 12 to 20% by weight and adjusting the amount of e-graphite to 20 to 28% by weight according to the change of glass fiber were measured using TM-1 method. Plain 2.47W / mK, TM-4 method through-plane 0.96W / mK, flexural modulus 8,880MPa, impact strength 91J / m, specific gravity 1.264. Injection flowability at 230 ° C. also showed good levels of spiral flow numbers in the range of 51-52.

Code number EX-75 EX-76 EX-77
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PP / EGG 40% (EX-23) 50 60 70 PP-LFT50 50 40 30 Heat stabilizer 0.2 0.2 0.2 e-graphite content (% by weight) 20 24 28 GF content (% by weight) 20 16 12



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importance 1.293 1.274 1.264 Flexural Strength (MPa) 128 122 110 Flexural modulus (MPa) 9,039 8,688 8,880 IZOD impact strength (J / m) 116 110 91 Heat deformation temperature (캜) 157 158 156 Surface resistance (Ω / □) 2 × 10 ⁴ 1 x 10 ⁴ 4 x 10 ³ Spiral Flow (cm) 53 51 52
Thermal conductivity
(W / mK)
TM1 2.109 2.260 2.471 TM2 - - 1.208 TM3 0.957 1.045 1.059

22 is a graph comparing the thermal conductivity of the PP / EGG thermally conductive composite and PP / EGG / LGF thermally conductive composite composition according to the e-graphite content, the thermally conductive composite composition by the long fiber is the same e-graphite content Compared to the (20% by weight) material, the thermal conductivity is improved by about 80% or more, which is an improvement in thermal conductivity beyond the so-called blend rule.

PA6-based (PA / EGG / PA6 / LGF composites prepared in Table 27 and PA6 / EGG thermally conductive composites (40% by weight of e-graphite) of Table 10 using the composition shown in Table 29 LGF) thermally conductive composite material was prepared. First, the PA / EGG / LGF thermally conductive composite composition exhibited specific gravity of 1.406 or less, flexural modulus of 5.7 GPa or more, thermal conductivity of 1.0W / mK or more, and spiral flow number of 51 or more.

Code number EX-78 EX-79 EX-80
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PP / EGG 40% (EX-23) 50 60 70 PP-LFT50 50 40 30 Heat stabilizer 0.2 0.2 0.2 e-graphite content (% by weight) 20 24 28 GF content (% by weight) 25 20 15


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importance 1.406 1.365 1.332 Flexural Strength (MPa) 155 122 89 Flexural modulus (MPa) 8,516 7,516 5,743 IZOD impact strength (J / m) 128 97 83 Heat deformation temperature (캜) 213 208 203 Surface resistance (Ω / □) 9 × 10 ⁸ 2 × 10 ⁸ 4 × 10 ⁷ Hardness (D) 75 74 70 Spiral Flow (cm) 51 51 54 Thermal conductivity
(W / mK) TM1 0.986 1.086 1.138 TM3 0.757 0.794 0.821

FIG. 23 is a graph comparing the thermal conductivity of the PA6 / EGG thermally conductive composite and the PA6 / EGG / LGF thermally conductive composite composition. As in the case of PP, the composite by EGG / LGF combination is about 20% better in both in-plane and through-plane thermal conductivity than the filler system of EGG alone. This synergistic effect was also observed in the PP / LGF complex, and it can be seen that LGF is an effective filler for the heat transfer path of graphite.

BN system Thermal conductivity  Apply to composite

The BN / LGF-based thermally conductive composite composition was prepared in the same manner as the graphite-based thermally conductive composite prepared by LGF reinforcement. Table 30 shows the composition and physical properties of the PP / BN10 / LGF thermally conductive composite composition. As a result of evaluating the physical properties of the injection specimen, the physical properties of the PP / BN / LGF thermally conductive composite material having a flexural modulus of 8,000 MPa or more, an impact strength of 73 J / m or more, and a specific gravity of 1.335 or less were obtained.

Code number EX-81 EX-82 EX-83
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PP / BN10 50% (EX-49) 40 50 60 PP-LFT50 60 50 40 Heat stabilizer 0.2 0.2 0.2 BN content (% by weight) 20 25 30 GF content (% by weight) 30 25 20

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importance 1.335 1.325 1.328 Flexural Strength (MPa) 130 116 116 Flexural modulus (MPa) 8,403 8,080 8,072 IZOD impact strength (J / m) 89 78 73 Heat deformation temperature (캜) 156 155 153 Surface resistance (Ω / □) > 10 ¹³ > 10 ¹³ > 10 ¹³ Spiral Flow (cm) 68 74 67 Thermal conductivity
(W / mK) TM1 0.433 0.461 0.489 TM3 0.564 0.627 0.645

The specimen EX-83, filled with 30% by weight of BN and 20% by weight of GF, has a thermal conductivity of 0.489 W / m · K in TM-in-plane and 0.645 W / m · K in through-plane of TM3. Self-assessed with the composition. The thermal conductivity of the PP / BN / LGF thermally conductive composite composition was compared with that of the PP / BN thermally conductive composite having the same BN content. As a result of evaluating the specimen EX-83 by the laser flash method, it was evaluated as in-plane 1.259 W / m · K and through-plane 0.846 W / m · K.

The synergistic effect of LGF on thermal conductivity is lower than that of graphite, which is due to the difficulty of the heat transfer network than that of e-graphite at low charge rate, and is due to the low thermal conductivity of BN itself. It is feed.

Table 31 shows the composition and physical properties of the PP / BG10 / LGF thermally conductive composite composition. In terms of mechanical properties, it was evaluated as a PP-based composite having a flexural modulus of 7,810 MPa or more, an impact strength of 64 J / m or more, and a specific gravity of 1.335 or less. It was confirmed that thermal conductivity is somewhat improved by the combination of LGF. Thermal conductivity was 0.484W / mK level in the through-plane of TM3 method, which is 25% lower than that of BN. The thermal conductivity of the PP / BG / LGF thermally conductive composite composition was lower than that of the PP / NB / LGF thermally conductive composite composition because the thermal conductivity of the PP / BG thermally conductive composite was lower than that of PP / BN (see Table 22). Not so surprising.

Code number EX-84 EX-85 EX-86
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PP / BG 50% (EX-50) 40 50 60 PP-LGF50 60 50 40 Heat stabilizer 0.2 0.2 0.2 BG10 content (% by weight) 20 25 30 GF content (% by weight) 30 25 20

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importance 1.380 1.382 1.383 Flexural Strength (MPa) 127 128 117 Flexural modulus (MPa) 8,675 8,808 7,810 IZOD impact strength (J / m) 66 64 64 Heat deformation temperature (캜) 157 158 156 Surface resistance (Ω / □) > 10 ¹³ > 10 ¹³ > 10 ¹³ Spiral Flow (cm) 85 81 82 Thermal conductivity
(W / mK) TM1 0.358 0.369 0.377 TM3 0.451 0.476 0.484

However, when the specimens of the same filling rate (BG filler = 20 wt%) of the PP / BG thermally conductive composite and the PP / BG / LFT thermally conductive composite composition were compared with each other, the thermal conductivity was improved by about 45%.

Table 32 shows the composition and physical properties of the PA6 / BN10 / LGF thermally conductive composite composition. All of the compositions have excellent physical properties. The mechanical properties were found to be at least 11.7 GPa flexural modulus, at least 51 J / m, and at least SFN 55.

Code number EX-87 EX-88 EX-89
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PP6 / BN50 (EX-39) 40 50 60 PA6-LGF50 60 50 40 Heat stabilizer 0.2 0.2 0.2 BN content (% by weight) 20 25 30 GF content (% by weight) 30 25 20

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importance 1.559 1.535 1.510 Flexural Strength (MPa) 219 200 181 Flexural modulus (MPa) 13,285 12,419 11,574 IZOD impact strength (J / m) 71 63 51 Heat deformation temperature (캜) 215 215 214 Hardness (D) 83 84 84 Surface resistance (Ω / □) > 10 ¹³ > 10 ¹³ > 10 ¹³ Spiral Flow (cm) 58 60 55 Thermal conductivity
(W / mK) TM1 0.523 1.092 1.228 TM3 0.839 0.902 0.943

24, thermal conductivity of the PP / BN / LGF thermally conductive composite composition and the PA6 / BN / LGF thermally conductive composite composition by LGF strengthening was compared. The thermal conductivity of the PA6 / BN / LGF thermally conductive composite composition was improved by about 2 times or more in in-plane and about 1.5 times in through-plane than the PP / BN / LGF thermally conductive composite composition. As both PP and PA6 are crystalline polymers and are expected to have similar levels of thermal conductivity unless they are affected by special crystal orientations, the difference in thermal conductivity between the two composite compositions under the same filler composition is surprising. In addition, the EX-39 specimens show almost the same thermal conductivity with in-plane 1.228 W / mK and through-plane 0.943 W / mK.

The above results suggest one possibility for the purpose of reducing the specific gravity of the thermally conductive composite composition (and ultimately increasing the price competitiveness) by making the thermally conductive network efficient with a small filler content.

Thermal conductivity  Flow Evaluation of Composites

Degradation of fluidity and deterioration of moldability due to high filling of the thermally conductive composite materials bring many problems in the manufacture of injection parts. Typical examples include unforming due to deterioration of fluidity and deformation after injection due to glass fiber reinforcement.

In order to improve the injection property, there are improvement measures such as controlling the size and shape of the charged particles, improving the flowability of the resin itself, and improving the flowability using an organic lubricant. It is necessary to lower. The flowability of the thermally conductive composites due to the high filling of the thermally conductive fillers was evaluated to determine the level.

First, the melt flow index (MFI) was measured in a Tinius Olsen melt index meter according to ASTM D1234 method according to the type of resin. PP was weighed at 2.16 kg at 230 ° C., and PA6 was discharged at 5 kg at 275 ° C. for 10 minutes.

Second, the spiral flow number (hereinafter referred to as 'SFN') in the ASTM standard mold using the injection molding machine was evaluated. Evaluation was made according to ASTM 3123. The degree of flow along the spiral flow groove at a constant pressure under injection conditions determined for each resin was measured and expressed in cm.

Graphite Thermal conductivity  Composite material

All of the graphite-based thermally conductive composites were evaluated to have a spiral flow number higher than 30. As shown in Table 33, the flowability of the thermally conductive composite material due to the high charge of general graphite and e-graphite decreased the flowability very rapidly according to the filler filling rate. Although the flowability level by MFI by graphite was very low, the injection SFN showed more than 55 injection molding. e-graphite had a smaller particle size than that of ordinary graphite, causing severe flow deterioration.

Table 33 shows the MFI and SFN of PP based thermally conductive composites according to graphite filling rate.

0 20% 30% 40% MFI SFN MFI SFN MFI SFN MFI SFN PP / SG 90
＞ 120
10 92 2 72 One 57 PP / EGG 8 91 0.4 67 0.1 55

Table 34 shows the spiral flow numbers of the PP / EGG thermally conductive composites and the PA6 / EGG thermally conductive composites according to the e-graphite filling rate.

e-graphite filling rate 0 20% 30% 40% PP / EGG ＞ 120 91 67 55 PA6 / EGG 95 85 67 56

Regardless of the PP or PA6 resin, SFN shows a linear decrease with increasing graphite filler content. In Table 35 below, the linear relationship between filler content and SFN can be more clearly seen.

BN system Thermal conductivity  Composite material

Both PP / BN thermally conductive composites and PA6 / BN thermally conductive composites have secured flowability over SFN 30. As shown in Table 35, the flowability of the thermally conductive composite material according to the BN and BG filling rates decreased as the filler filling rate increased. Compared to graphite, the degree of flow loss due to BN material was lower, and this result shows a similar tendency to the result of the maximum filling rate of the continuously prepared fillers identified in the compound process. That is, in the case of graphite, the maximum filling rate was 40% by weight, and in the case of BN, the maximum filling rate was 50% by weight.

0 20% 30% 40% 50% MFI SFN MFI SFN MFI SFN MFI SFN MFI SFN PP / BN 90
＞ 120
67 116 33 91 18 73 4 58 PP / BG 67 94 - - - - 32 78 PA6 / BN 115
95
11 55 10 52 2 43 One 36 PA6 / BG 12 56 - - - - 3 41

In general, PP-based composites, which are used as component materials, are advantageous for large-area injection parts in which SFN levels are designed to be at least 50 cm, and in the case of PA6, it is advantageous for injection of complex flow patterns. Filling 50% by weight of BN in a high flow PP of 90 g / 10 min of MFI, the PP / BN thermally conductive composite showed a very low MFI of 4 g / 10 min, while the SFN was 58 cm. PA6 / BN thermally conductive composites exhibit lower levels of flow than PP / BN thermally conductive composites. PA6 / BN thermally conductive composites have a certain amount of injection flow with MFI = 2g / 10 min at 40% by weight filling and SFN = 36 cm.

In the evaluation of the flow due to the filling of BG, the PP / BG thermally conductive composite shows a high level of flowability of MFI = 32 g / 10 min and SFN = 78 cm at a high 50 wt% charge. These results may be due to the hybrid shape of plate and sphere.

FIG. 25 is a graph of comprehensively analyzing SFN and MFI according to BN content of PP / BN, PA6 / BN, PP / EGG, and PA6 / EGG thermally conductive composites. The Y-axis scale of the graph is displayed by the log function. In the graph, the MFI decreases linearly with increasing filler content, indicating that the MFI of the composite changes as a function of exponential decay, depending on the filler filling rate.

FIG. 26 is a graph illustrating changes in SFNs of PP / LGF composites and PA6 / LGF composites according to LGF content, and SFN changes of composites reinforced with LGF in thermally conductive fillers having a maximum filling rate of the corresponding resin. All composite materials with a filler filling rate of 50% or less satisfy SFN> 50, regardless of the composition of the filler. These results indicate that long fibers and nanoclays have a great influence on the development of a thermally conductive composite composition having sufficient injection flow properties to be achieved in the present invention.

Compared with the PP / LGF composite and the PA6 / LGF composite, the initial injection flow of the superior PP resin decreased linearly while maintaining better flowability than the PA6-based composite. In the case of SFN of the composite reinforced with LGF, when the total filler content is displayed in the graph as a variable, it is observed that there is no significant difference between the compositions within the experimental error range and follows the linear equation.

While the present invention has been particularly shown and described with reference to exemplary embodiments thereof, it is to be understood that the invention is not limited to the disclosed exemplary embodiments, This is possible.

110: main feeder 120: shaft
130: cylinder 140a, 140b, 140c:
150: heating means 160: discharge die
155: blower 165: cooling pipe
170: side feeder 180: frame
190: Bentport

Claims (25)

At least one selected from polyolefin resin, polyamide resin, polybutylene terephthalate resin, acrylonitrile butadiene styrene copolymer, polycarbonate resin, polyester resin, polyphenylene sulfide resin and thermoplastic elastomer resin Thermoplastic resins;
At least one thermally conductive filler selected from expanded graphite and nitrogen boride discontinuously and uniformly dispersed in the thermoplastic resin; And
It includes dispersing uniformly dispersed in the thermoplastic resin and long fibers having a square ratio of 50 to 3000,
The thermally conductive filler is contained 0.1 to 90 parts by weight based on 100 parts by weight of the thermoplastic resin,
The long fiber is a thermally conductive composite material composition, characterized in that containing 0.1 to 90 parts by weight based on 100 parts by weight of the thermoplastic resin.
The method of claim 1, wherein the thermally conductive composite material composition further comprises a carbon nanotube discontinuously and uniformly dispersed in the thermoplastic resin, the carbon nanotube is 0.1 to 10 parts by weight based on 100 parts by weight of the thermoplastic resin A thermally conductive composite material composition, characterized in that it contains.
The method of claim 1, wherein the thermally conductive composite composition further comprises a nanoclay discontinuously and uniformly dispersed in the thermoplastic resin, the nanoclay is contained 0.1 to 10 parts by weight based on 100 parts by weight of the thermoplastic resin Thermally conductive composite material composition characterized in that.
The method of claim 1, wherein the thermally conductive composite material composition further comprises at least one material selected from talc and calcium carbonate discontinuously and uniformly dispersed in the thermoplastic resin, at least one selected from the talc and calcium carbonate The material is a thermally conductive composite material composition, characterized in that containing 0.1 to 10 parts by weight based on 100 parts by weight of the thermoplastic resin.
The method of claim 1, wherein the thermally conductive composite material composition further comprises an organic nucleating agent discontinuously and uniformly dispersed in the thermoplastic resin, the organic nucleating agent is contained 0.1 to 10 parts by weight based on 100 parts by weight of the thermoplastic resin And wherein the organic nucleating agent comprises an organic carboxylate or an organophosphate.
The method of claim 1, wherein the thermally conductive composite material composition further comprises a rubber that is discontinuously and uniformly dispersed in the thermoplastic resin, wherein the rubber is contained 5 to 40 parts by weight based on 100 parts by weight of the thermoplastic resin Thermally conductive composite material characterized in that.
The method of claim 1, wherein the expanded graphite is a powder-like expansion having graphite is connected to each other after the graphite is peeled at a temperature higher than 300 ℃ after being purified by sulfuric acid, hydrogen peroxide and NH ₄ S ₂ O ₈ Thermally conductive composite composition, characterized in that made of graphite.
8. The thermally conductive composite according to claim 7, wherein the expanded graphite is a graphite plate peeled off with particulate expanded graphite having a soft particulate form formed by compacting the powdered expanded graphite. Material composition.
The method of claim 1, wherein the nitrogen boride is made of a nitrogen boride-based composite formed by hybridization of nitrogen boride and magnesium oxide (MgO), the magnesium oxide is 100 parts by weight of nitrogen boride in the nitrogen boride-based composite 5 to 40 parts by weight relative to the thermally conductive composite material composition.
According to claim 1, wherein the long fiber is composed of one or more long fibers selected from glass fibers, carbon fibers and organic fibers, the long fiber is a thermally conductive composite material composition characterized in that it has a length of 0.1 ~ 20㎜ .
(a) selected from polyolefin resin, polyamide resin, polybutylene terephthalate resin, acrylonitrile butadiene styrene copolymer, polycarbonate resin, polyester resin, polyphenylene sulfide resin, and thermoplastic elastomer resin Introducing at least one thermoplastic resin into a twin screw extruder;
(b) rotating the shaft to melt and compress at a temperature higher than the melting temperature of the thermoplastic resin while mixing the thermoplastic resin in the cylinder of the twin screw extruder;
(c) the shafts of the twin screw extruder are rotated in a predetermined direction so that shear stress is applied to the molten and compressed thermoplastic resin, and at least one thermally conductive filler selected from expanded graphite and nitrogen boride and Adding 50 to 3000 long fibers through a side feeder to uniformly disperse them in the thermoplastic resin;
(d) discharging the composition in a twin screw extruder by rotating the shaft to apply a higher shear stress in step (c) while heating to a higher temperature than step (c); And
(e) cooling and cutting to obtain a thermally conductive composite composition,
The thermally conductive filler is added in an amount of 0.1 to 90 parts by weight based on 100 parts by weight of the thermoplastic resin,
The long fiber is 0.1 to 90 parts by weight based on 100 parts by weight of a thermoplastic resin manufacturing method of the thermally conductive composite material composition.
(a) selected from polyolefin resin, polyamide resin, polybutylene terephthalate resin, acrylonitrile butadiene styrene copolymer, polycarbonate resin, polyester resin, polyphenylene sulfide resin, and thermoplastic elastomer resin Preparing a resin-long fiber composite material in which long fibers having a square ratio of 50 to 3000 are discontinuously and uniformly dispersed in at least one thermoplastic resin;
(b) selected from polyolefin resin, polyamide resin, polybutylene terephthalate resin, acrylonitrile butadiene styrene copolymer, polycarbonate resin, polyester resin, polyphenylene sulfide resin, and thermoplastic elastomer resin Introducing at least one thermoplastic resin and the resin-long fiber composite into a twin screw extruder;
(c) rotating the shaft to melt and compress at a temperature higher than the melting temperature of the thermoplastic resin while mixing the thermally conductive resin and the resin-long fiber composite in the cylinder of the twin screw extruder;
(d) The shafts of the twin screw extruder are rotated in a predetermined direction so that shear stress is applied to the melted and compressed products, and at least one thermally conductive filler selected from expanded graphite and nitrogen boride is used as a side feeder. Adding through to disperse uniformly in the thermoplastic resin;
(e) discharging the composition in a twin screw extruder by rotating the shaft to apply a higher shear stress in step (d) while heating to a temperature higher than step (d); And
(f) cooling and cutting to obtain a thermally conductive composite composition,
The thermally conductive filler is to be contained 0.1 to 90 parts by weight with respect to 100 parts by weight of the thermoplastic resin,
The long fiber is 0.1 to 90 parts by weight based on 100 parts by weight of a thermoplastic resin manufacturing method of the thermally conductive composite material composition.
(a) selected from polyolefin resin, polyamide resin, polybutylene terephthalate resin, acrylonitrile butadiene styrene copolymer, polycarbonate resin, polyester resin, polyphenylene sulfide resin, and thermoplastic elastomer resin Preparing a thermally conductive composite in which at least one thermally conductive filler selected from expanded graphite and nitrogen boride is discontinuously and uniformly dispersed in at least one thermoplastic resin;
(b) selected from polyolefin resin, polyamide resin, polybutylene terephthalate resin, acrylonitrile butadiene styrene copolymer, polycarbonate resin, polyester resin, polyphenylene sulfide resin, and thermoplastic elastomer resin Preparing a resin-long fiber composite material in which long fibers having a square ratio of 50 to 3000 are discontinuously and uniformly dispersed in at least one thermoplastic resin;
(c) injecting the thermally conductive composite and the resin-long fiber composite into a twin screw extruder;
(d) rotating the shaft to melt and compress at a temperature above the melting temperature of the thermoplastic resin while mixing the thermally conductive composite and the resin-long fiber composite in a cylinder of the twin screw extruder;
(e) rotating the shafts of the twin screw extruder in a predetermined direction such that shear stress is applied to the melted and compressed products so that the thermally conductive filler and the long fibers are uniformly dispersed in the thermoplastic resin;
(f) discharging the composition in a twin screw extruder by rotating the shaft to apply a higher shear stress in step (e) while heating to a temperature higher than step (e); And
(g) cooling and cutting to obtain a thermally conductive composite composition,
The thermally conductive filler is to be contained 0.1 to 90 parts by weight with respect to 100 parts by weight of the thermoplastic resin,
The long fiber is 0.1 to 90 parts by weight based on 100 parts by weight of a thermoplastic resin manufacturing method of the thermally conductive composite material composition.
(a) selected from polyolefin resin, polyamide resin, polybutylene terephthalate resin, acrylonitrile butadiene styrene copolymer, polycarbonate resin, polyester resin, polyphenylene sulfide resin, and thermoplastic elastomer resin Preparing a thermally conductive composite in which at least one thermally conductive filler selected from expanded graphite and nitrogen boride is discontinuously and uniformly dispersed in at least one thermoplastic resin;
(b) selected from polyolefin resin, polyamide resin, polybutylene terephthalate resin, acrylonitrile butadiene styrene copolymer, polycarbonate resin, polyester resin, polyphenylene sulfide resin, and thermoplastic elastomer resin Preparing a resin-long fiber composite material in which long fibers having a square ratio of 50 to 3000 are discontinuously and uniformly dispersed in at least one thermoplastic resin;
(c) mixing the thermally conductive composite and the resin-long fiber composite by injecting the injector;
(d) injecting the composition in the injection machine; And
(e) cooling to obtain a thermally conductive composite composition,
The thermally conductive filler is to be contained 0.1 to 90 parts by weight with respect to 100 parts by weight of the thermoplastic resin,
The long fiber is 0.1 to 90 parts by weight based on 100 parts by weight of a thermoplastic resin manufacturing method of the thermally conductive composite material composition.
The method according to any one of claims 11 to 13, further comprising adding carbon nanotubes through a side feeder in a process of causing shear stress to be applied to the melted and compressed products. The method for producing a thermally conductive composite material composition characterized in that the addition of 0.1 to 10 parts by weight based on 100 parts by weight of the thermoplastic resin.
14. The method of any one of claims 11 to 13, further comprising adding nanoclays through a side feeder in the course of causing shear stress to be applied to the melted and compressed products, wherein the nanoclays are thermoplastic 0.1-10 weight part with respect to 100 weight part of resin, The manufacturing method of the heat conductive composite material composition characterized by the above-mentioned.
14. The method of any one of claims 11 to 13, further comprising adding at least one material selected from talc and calcium carbonate through a side feeder in the course of causing shear stress to be applied to the melted and compressed product. And at least one material selected from talc and calcium carbonate is added in an amount of 0.1 to 10 parts by weight based on 100 parts by weight of the thermoplastic resin.
The method according to any one of claims 11 to 13, further comprising the step of adding an organic nucleating agent through a side feeder in the process of causing shear stress to be applied to the melted and compressed product, wherein the organic nucleating agent is thermoplastic 0.1 to 10 parts by weight based on 100 parts by weight of resin, wherein the organic nucleating agent comprises an organic carboxylate or an organic phosphate method of producing a thermally conductive composite material composition.
14. The method of any one of claims 11 to 13, further comprising adding rubber through a side feeder in the course of causing shear stress to be applied to the melted and compressed product, wherein the rubber is made of thermoplastic resin 100. A method for producing a thermally conductive composite composition, characterized in that 5 to 40 parts by weight based on parts by weight.
15. The graphite plate according to any one of claims 11 to 14, wherein the expanded graphite is exfoliated at a temperature higher than 300 ° C after the graphite is purified with sulfuric acid, hydrogen peroxide and NH ₄ S ₂ O ₈ . Method for producing a thermally conductive composite material composition characterized in that the powder consisting of expanded graphite having a transmission path.
21. The thermally conductive composite according to claim 20, wherein the expanded graphite is a graphite plate peeled off with particulate expanded graphite having a soft particulate form formed by compressing the powdered expanded graphite. The expanded graphite has a crystal size of 10 to 200 nm. Method for producing the material composition.
15. The method of any one of claims 11 to 14, wherein the nitrogen boride is made of a nitrogen boride-based composite formed by hybridizing nitrogen boride and magnesium oxide (MgO), the magnesium oxide is the nitrogen boride-based 5 to 40 parts by weight based on 100 parts by weight of nitrogen boride in the composite material.
The long fiber according to any one of claims 11 to 14, wherein the long fiber is made of one or more long fibers selected from glass fibers, carbon fibers, and organic fibers, and the long fibers have a length of 0.1 to 20 mm. Method for producing a thermally conductive composite material composition, characterized in that.
The method according to any one of claims 12 to 14, wherein the step of preparing the resin-long fiber composite,
At least one selected from polyolefin resin, polyamide resin, polybutylene terephthalate resin, acrylonitrile butadiene styrene copolymer, polycarbonate resin, polyester resin, polyphenylene sulfide resin and thermoplastic elastomer resin Introducing a thermoplastic resin into a twin screw extruder;
Rotating the shaft to melt and compress at a temperature higher than the melting temperature of the thermoplastic resin while mixing the thermoplastic resin in the cylinder of the twin screw extruder;
Rotating the shafts of the twin screw extruder in a predetermined direction so that shear stress is applied to the molten and compressed thermoplastic resin, and adding long fibers having an angular ratio of 50 to 3000 through a side feeder to uniformly disperse them in the thermoplastic resin. ;
Discharging the resin-long fiber composite material in a twin screw extruder by rotating the shaft to apply a higher shear stress in the dispersing step while heating to a higher temperature than the dispersing step; And
Cooling and cutting to obtain a resin-long fiber composite,
The long fiber is 0.1 to 90 parts by weight based on 100 parts by weight of a thermoplastic resin manufacturing method of the thermally conductive composite material composition.
The method of claim 13 or 14, wherein the step of preparing the thermally conductive composite,
At least one selected from polyolefin resin, polyamide resin, polybutylene terephthalate resin, acrylonitrile butadiene styrene copolymer, polycarbonate resin, polyester resin, polyphenylene sulfide resin and thermoplastic elastomer resin Introducing a thermoplastic resin into a twin screw extruder;
Rotating the shaft to melt and compress at a temperature higher than the melting temperature of the thermoplastic resin while mixing the thermoplastic resin in the cylinder of the twin screw extruder;
The shafts of the twin screw extruder are rotated in a predetermined direction so that shear stress is applied to the molten and compressed thermoplastic resin, and at least one thermally conductive filler selected from expanded graphite and nitrogen boride is added through the side feeder. Uniformly dispersing in the thermoplastic resin;
Discharging the thermally conductive composite material in a twin screw extruder by rotating the shaft to apply a higher shear stress in the dispersing step while heating to a higher temperature than the dispersing step; And
Cooling and cutting to obtain a thermally conductive composite,
The thermally conductive filler is a method for producing a thermally conductive composite material composition characterized in that the addition of 0.1 to 90 parts by weight based on 100 parts by weight of the thermoplastic resin.

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