KR100885653B1 - Hybrid filler type resin composition for high thermal conductivity - Google Patents

Abstract

A composite resin composition is provided to improve thermal conductivity, tensile strength, impact resistance and flextural modulus by using a hybrid filler of fiber filler having the thermal conductivity of 200 W / mK or greater and a particle type filler. A composite resin composition(10) comprises a hybrid filler(150) of a fiber type filler and a particle type filler, dispersed through the whole volume of a polymer matrix containing polyether etherketone. The polymer matrix further includes one selected from polyethylene, polypropylene, polystyrene, polycarbonate, polyamide, polyethersulfide, polyphenylenesulfide, liquid-crystal polymer and polyetheramide.

Description

Hybrid filler type resin composition for high thermal conductivity

The present invention relates to a composite resin composition in contact with the polymer resin by filling the hybrid filler using a filler in the form of two or more of fiber-shaped filler, particle-shaped filler, plate-shaped filler, needle-shaped filler at the same time more than 5 It is about a thermally conductive composite resin composition to improve the processability and mechanical properties while increasing the thermal conductivity.

Until recently, only metal and ceramic materials with high thermal conductivity were used in applications requiring fast heat transfer. However, these materials have limited workability due to poor workability, and these materials are relatively expensive and heavier than plastics. It has the drawback of having weight.

In order to solve this problem, studies using metal fillers or ceramic fillers having high thermal conductivity in polymer resins have been conducted.

In general, plastics are used for many applications because of their lightness and moldability, and are continuously replacing metals and ceramics.

In particular, as electronic products use parts that are thinner, lighter, and generate more heat, there is a greater demand for plastic housings and components having excellent heat dissipation.

In general, plastics have excellent electrical insulation and low thermal conductivity, which is excellent as a heat insulating / insulating material.

However, plastics are poor in heat dissipation, so when used for the housing of electronic products, the internal temperature is increased, causing malfunctions, etc., and when the temperature is high, the use of the plastic is not sufficient, so that the use of the plastic is limited.

Polymers such as plastics have a very low thermal conductivity because polymers have a long chain shape and are scattered in the heat transfer process in which energy is transferred by a phonon.

In general, thermal conductivity can be obtained from thermal diffusivity through the following equation.

K = α ρ Cp (1)

In Equation (1), k is thermal conductivity, α = thermal diffusivity, ρ = density, and Cp = specific heat.

Polymers such as plastics have a property that heat conduction does not pass well about 0.17 ~ 0.4 W / mK.

Therefore, a study has been attempted to form a thermally conductive polymer resin by adding a thermally conductive filler to a polymer such as plastic.

Korean Patent 20-0339260 describes a heating panel using a polymer resin having a thermal conductivity of 1 W / mK or more, but details of the thermal conductive resin composition are not described.

In addition, although Korean Patent No. 20-0338520 describes a printed circuit board using a heat dissipating resin, a specific technology for a thermally conductive resin is not described.

In U.S. Patent No. 5,232,970, the thermal conductivity was increased by filling only 35% by volume of ceramic granules in plastic, and Yu et al. (Diamond & related materials, 2005) contained 30 vol. % Was added to increase to 1.2 W / mK, it was confirmed that the alumina or diamond, such as the shape of the particles give a better thermal contact effect.

Korean Patent No. 10-0450229 shows that the thermal conductivity is increased to about 0.9 to 1.6 W / mK when various fillers are added in excess of 40 wt% with respect to various polymers. Particularly, the fibrous fillers and the particulate fillers No synergy is mentioned.

These studies have a thermal conductivity of about 1 W / mK only when a large amount is added, and there is a problem in that workability and mechanical properties are degraded by the addition of many fillers.

The present invention is to improve the above problems, two or more of the filler in the form of fiber, filler in the form of particles, filler in the form of a plate, filler in the form of a needle having an aspect ratio of 5 or more in the polymer resin containing polyether ether ketone. It is an object of the present invention to provide a composite resin composition in which the used hybrid filler is increased to increase contact between the fillers, thereby improving thermal conductivity.

And an object of the present invention is to provide a composite resin composition that can be used for applications requiring mechanical properties and heat resistance by adding carbon fiber to the polymer resin.

Another object of the present invention is to provide a composite resin composition which can be easily processed by an extruder or a general kneader.

The composite resin composition for solving the above technical problem is characterized in that the hybrid filler mixed with the fibrous filler and the particulate filler is dispersed throughout the volume of the polymer matrix including the polyether ether ketone.

Here, the content of the polymer constituting the polymer matrix based on 100 parts by volume of the composite resin composition is 30 to 95 parts by volume, and the hybrid filler is characterized in that it consists of a ratio of 5 to 70 parts by volume.

In addition, the content of the polymer constituting the polymer matrix based on 100 parts by volume of the composite resin composition is characterized in that consisting of 60 to 90 parts by volume, the hybrid filler is 10 to 40 parts by volume.
Here, the polymer matrix is a copolymer of a resin further comprising at least one of polyethylene, polypropylene, polystyrene, polycarbonate, polyamide, polyether sulfide, polyphenylene sulfide, liquid crystal polymer, and polyetheramide. do.

In addition, the hybrid filler is characterized in that the thermal conductivity of 200W / mK or more.

Wherein the fibrous filler is characterized by having an aspect ratio of 5 or more.

In addition, the fibrous filler is characterized in that the thermal conductivity of carbon fiber of 200 W / mK or more. At this time, the carbon fiber is characterized by adding 10 parts by volume or more.

In addition, the particulate filler is characterized in that at least one of alumina, boron nitride, silicon carbide, diamond, beryllium oxide, aluminum nitride is selected, the average diameter is 30㎛ or less.

The composite resin composition is characterized in that the thermal conductivity is 3W / mk or more, characterized in that the tensile strength is 100 to 200MPa, impact strength is characterized in that 4KJ / m ² to 8KJ / m ² , flexural strength It is characterized in that 140 to 250MPa, the flexural modulus is characterized in that 8000 to 12000 MPa.

In addition, a display device for solving the above technical problem is a display panel for displaying an image; Covering the display panel, and comprises a cover formed of the composite resin composition.

As described above, the composite resin composition according to the present invention has an effect of improving the thermal conductivity of the composite resin composition by using a hybrid filler using a mixture of fiber filler and particulate filler having a thermal conductivity of 200 W / mK or more.

The composite resin composition according to the present invention has an effect of improving mechanical properties such as tensile strength, impact strength, flexural modulus, as well as thermal conductivity by using a mixture of fibrous fillers and particulate fillers.

In addition, since the polymer resin is used as the thermoplastic resin, it is easy to process into various shapes, thereby improving workability.

Hereinafter, the composite resin composition according to the embodiments of the present invention will be described with reference to specific examples and comparative examples that are excellent in thermal conductivity and mechanical properties.

Details not described herein are omitted because they can be sufficiently inferred by those skilled in the art.

1 is a view showing a composite resin composition according to the present invention.

Referring to FIG. 1, the composite resin composition 10 according to the present invention includes a polymer resin forming a polymer matrix and a hybrid filler dispersed in the polymer matrix.

The composite resin composition according to the present invention may further include additives such as a release agent, a light stabilizer, a heat stabilizer, an ultraviolet absorber, a flame retardant, a colorant, a lubricant, an antistatic agent, and an inorganic filler.

The volume content of the polymer resin 110 may be formed in a composition of 30 to 95 parts by volume based on 100 parts by volume of the total volume of the composite resin composition 10.

The polymer resin 110 may be a thermoplastic resin.

The thermoplastic resin includes polyethylene, polypropylene, polystyrene, polycarbonate, polyamide, polyether ether keytone, polyether sulfide, polyphenylene sulfide, liquid crystal polymer, polyetheramide, and a resin containing at least one of them. The copolymer of can be used.

The volume content of the hybrid filler 150 may be composed of 5 parts to 70 parts by volume or less based on 100 parts by volume of the total volume of the composite resin composition 10. Preferably from 10 to 40 parts by volume can be used.

This is because, when the content of the hybrid filler 150 is 70 parts by volume or more, the extrusion process or the injection process becomes difficult due to the increase in the viscosity of the composite resin composition 10 and may cause a sudden drop in impact strength.

And the thermal conductivity of the hybrid filler 150 preferably has a 200W / mK or more.

The hybrid filler 150 may be used as a ceramic filler. This is because metal-based fillers such as aluminum flakes and copper fibers have excellent thermal conductivity, but have high electrical conductivity, and thus cannot retain the electrical insulation advantages of the polymer resin (110). This is because it may cause deterioration of physical properties. Here, as the ceramic filler, those having a particle shape, a plate shape, a needle shape, or the like can be used.

And the hybrid filler 150 of the present invention may be composed of a fibrous filler 130 and a particulate filler (120).

delete

The fibrous filler 130 may be added to 3 to 40 parts by volume based on a total of 100 parts by volume of the composite resin composition.

The addition of the fibrous filler 130 may be important in the production of moldings requiring maintenance of impact strength and tensile strength.

The hybrid filler 150 may have an aspect ratio of the fibrous filler 130 of 5 or more, and preferably 20 or more, in order to have a synergistic heat transfer effect.

When only the fibrous filler 130 is added to the composite resin composition 10, the flowability of the composite resin composition 10 is not good, and the flow of the fiber at the time of injection aligns the fibers only in one direction so that the composite resin composition 10 ) There is a disadvantage that can cause severe directionality of the physical properties.

In addition, the fibrous filler 130 has an aspect ratio of 5 or more and thermal conductivity of 200 W / mK or more based on a total of 100 parts by volume based on the total volume of the composite resin composition, the composite resin composition 10 of The heat deflection temperature (ASTM D648) can be raised, thereby improving thermal conductivity and ensuring thermal stability of the polymer molded article. That is, the fibrous filler may serve as a heat conduction passage of the composite resin composition.

On the other hand, the particulate filler 120 may be added to 3 to 40 parts by volume based on a total of 100 parts by volume of the composite resin composition (10).

The particulate filler 120 includes one or more particles having high thermal conductivity such as alumina, boron nitride, silicon carbide, diamond, beryllium oxide, aluminum nitride, and the like.

The particulate filler 120 may use particles having an average diameter of 1 to 100 μm, preferably particles within 30 μm.

When the average diameter of the particulate filler 120 is 100 μm or more or only the particulate filler 120 is used in the composite resin composition 10, the impact property of the composite resin composition 10 may deteriorate rapidly, and the polymer material may have brittleness. have.

Here, the composite resin composition 10 formed by the present invention can be easily molded by injection molding, compression molding, or the like. Preferably, the injection molding is a processing method of a suitable form.

Hereinafter, a brief description of the manufacturing process to explain the improved processability of the composite resin composition according to the present invention.

In the present invention, the mixing of the polymer resin 110 and the particulate filler 120 may be a mixer-type kneader, preferably a single screw or twin screw extruder, and in particular, when the twin screw extruder is used, the filler kneading effect is excellent. Do. That is, the composite resin composition 10 according to the present invention has the advantage of easy processability.

In addition, in the extrusion process, the polymer resin 110 and the particulate filler 120 are premixed and added, or the polymer resin 110 and the particulate filler 120 and the thermoelectric are supplied by using two or more raw material feeders. Moral fiber and the like can be added.

In this case, it is important that the aspect ratio of the fibrous filler 130 that plays a major role in the heat conduction passage is not reduced during processing.

Therefore, in order to prevent the improvement of thermal conductivity and the deterioration of polymer properties by maintaining the aspect ratio of the fibrous filler 130, it is preferable to use the feed position of the fibrous filler 130 as the rear end of the extruder barrel in the extrusion process.

2 is a view showing a display device formed of a composite resin composition according to the present invention. Here, the composite resin composition refers to FIG. 1.

Referring to FIG. 2, the display device 20 includes a display panel 210 and a cover 10a formed of the composite resin composition according to the present invention.

The display panel 20 may display an image, and in order to operate the display panel 210, a plurality of electronic devices having a high degree of integration are provided in the display element 20.

The highly integrated electronic devices emit a lot of heat while operating. The heat may be a factor for degrading the performance of the display device 20.

The cover 10a may be molded into the composite resin composition 10 according to the present invention. Since the composite resin composition 10 according to the present invention has easy processing characteristics by the polymer resin 110, the composite resin composition 10 may be easily formed in various shapes.

In addition, since the cover 10a formed of the composite resin composition 10 includes the hybrid filler 150, heat is rapidly dissipated, thereby lowering the operating temperature of the display device 20, thereby improving durability of the product and extending the life. You can.

As such, the display device 20 using the composite resin composition 10 according to the present invention has an effect of extending durability and life of the device.

The present invention will be described in more detail with reference to the following examples and comparative examples. However, the examples are only for illustrating the present invention, but the scope of the invention is not limited.

Prior to the description of the embodiments will be briefly described the material of the polymer resin, hybrid filler used in the embodiment.

Polyetheretherketone (Polyetheretherketone) used in the embodiment of the polymer resin according to the present invention is one of high heat resistance engineering plastics and is widely used in compound form for electric and electronic applications.

It has been used in semiconductor production line process such as wafer tray, LCD cassette rack, etc. by improving the modulus of elasticity, flowability, low temperature impact, and fluidity by using polyether ether keytone resin and inorganic filler, glass fiber, antioxidant, and other additives. .

Polyether ether keytone resin mainly used in the present invention was used Victrex's 150P products and the detailed properties are shown in Table 1.

Physical properties of ceramic fillers used in this experiment are shown in Table 2. Table 3 shows the properties of Cytec's DKD pitch carbon fiber with high thermal conductivity and K223 carbon fiber with Mitsubishi Chemical's low thermal conductivity of 15 W / mK. The physical properties of the injection molded specimens were measured by the following method.

And the material prepared as described above was made from the injection specimen to make a disk-shaped specimen having a diameter of 10 mm and a thickness of 1 mm to measure the thermal diffusivity.

Thermal diffusivity was measured using a UL7000 TC7000 equipment. Tensile strength is ASTM D638, impact strength is ASTM D256, flexural strength is ASTM D790, flexural modulus is ASTM D790, tensile elongation is ASTM D638, thermal conductivity is measured by the Laser Flash Method.

Thermal conductivity, mechanical properties, and composition of Examples and Comparative Examples are shown in Tables 4 to 7.

Example 1

10% by volume of DKD (Cytec) fiber, a pitch-based carbon fiber, and 10% by volume of SiC in a particulate filler with a fibrous filler in 80% by volume polyether ether ketone granule resin. After mixing while rotating for a minute, pellets were prepared through a twin screw extruder having a diameter of 25 mm. The extruded pellets were dried at 130 ° C. for 4 hours, and then the specimens were manufactured by injection molding.

Example 2

It was prepared as in Example 1 by mixing 15% by volume of DKD fiber, a pitch-based carbon fiber, and 5% by volume of SiC as a particulate filler in a 80% by volume polyether ether ketone granule resin as a fibrous filler.

Example 3

80% by volume of polyether ether ketone granule resin was prepared as in Example 1 by mixing 5% by volume of pitch-based carbon fiber DKD fiber as a fibrous filler and 15% by volume of SiC as a particulate filler.

Example 4

70% by volume of polyether ether ketone resin was prepared by mixing 20% by volume of SiC and 10% by volume of DKD carbon fiber as a particulate filler.

Example 5

Polycarbonate (Samyang, Grade Trirex 3022) was prepared in Example 1 by mixing 15% by volume of pitch-based carbon fiber DKD fiber, 15% by volume of SiC as a particulate filler in a granular resin 70% by volume granular resin.

Example 6

70% by volume of polyether ether ketone resin was prepared in the same manner as in Example 1 by mixing 15% by volume of pitch-based carbon fiber DKD fiber as a fibrous filler and 15% by volume of AlN as a particulate filler.

Comparative Example 1

It was prepared as in Example 1 by mixing 20% by volume of SiC with a particulate filler in 80% by volume of polyether ether keytone resin.

Comparative Example 2

It was prepared as in Example 1 by mixing 20% by volume of DKD carbon fiber in 80% by volume of the polyether ether ketone resin.

Comparative Example 3

It was prepared in Example 1 by mixing 20% by volume of K223 carbon fiber and 10% by volume of particulate filler in 70% by volume of polyether ether keytone resin. And K223 carbon fiber has a low thermal conductivity of 15.

Table 4 is a table summarizing the compositions of Examples 1 to 6.

Here, the hybrid filler was changed to form a composite resin composition, respectively.

Table 5 is a table summarizing the thermal conductivity properties and mechanical property values of Examples 1 to 6.

As summarized in Table 5, the composite resin composition using the hybrid filler was measured 3W / mk or more in the thermal conductivity.

Tensile strength was measured from 100 to 200 MPa, and impact strength was measured from 4 KJ / m ² to 8 KJ / m ² . Flexural strength and flexural modulus were measured at 140 to 250 MPa and 8000 to 12000 MPa, respectively.

Table 6 shows Comparative Examples 1 to 3, and summarizes the composite resin composition mixed while changing the composition of the particulate filler or the fibrous filler other than the hybrid filler.

Table 7 is a table summarizing the thermal conductivity properties and mechanical property values of Comparative Examples 1 to 3.

As summarized in Table 7, the resin composition using the fibrous filler or particulate filler was measured at less than 2.5 W / mk in thermal conductivity.

Tensile strength of 50 to 200 MPa was measured, and impact strength of 4 KJ / m ² to 8 KJ / m ² was measured. The flexural strength and flexural modulus were measured as 100 to 300 MPa and 5000 to 10000 MPa, respectively.

In addition, k223, a carbon fiber having a low thermal conductivity of 15 W / mK, showed no significant thermal conductivity improvement of the composite resin composition even though it was a hybrid filler.

It can be seen that the resin composition according to the present invention has a higher tensile strength, higher impact strength, and a higher thermal conductivity than a resin composition containing no ceramic filler or a single ceramic filler.

Therefore, the composite resin composition may be used in heat exchangers or display parts.

1 is a view showing a composite resin composition according to the present invention.

2 is a view showing a display device formed of a composite resin composition according to the present invention.

Claims (17)

A hybrid resin composition comprising a fibrous filler and a particulate filler mixed therein is dispersed throughout the volume of the polymer matrix including polyether ether keytone. The method of claim 1, The content of the polymer constituting the polymer matrix based on 100 parts by volume of the composite resin composition is 30 to 95 parts by volume, the hybrid filler is a composite resin composition, characterized in that consisting of 5 to 70 parts by volume. The method of claim 1, The content of the polymer constituting the polymer matrix based on 100 parts by volume of the composite resin composition is 60 to 90 parts by volume, the hybrid filler is a composite resin composition, characterized in that consisting of 10 to 40 parts by volume. delete The method of claim 1, The polymer matrix is a copolymer of a resin further comprising at least one of polyethylene, polypropylene, polystyrene, polycarbonate, polyamide, polyether sulfide, polyphenylene sulfide, liquid crystal polymer, and polyetheramide. Resin composition. The method of claim 1, The hybrid filler is a composite resin composition, characterized in that the thermal conductivity of 200W / mK or more. The method of claim 1, Composite resin composition, characterized in that the aspect ratio of the fibrous filler is 5 or more. The method of claim 1, The fibrous filler is a composite resin composition, characterized in that the thermal conductivity of the carbon fiber 200 W / mK or more. The method of claim 8, The carbon fiber is a composite resin composition, characterized in that for adding at least 10 parts by volume based on 100 parts by volume of the composite resin composition. The method of claim 1, The particulate filler is a composite resin composition, characterized in that the average diameter is 30㎛ or less. The method of claim 1, The particulate filler is a composite resin composition characterized in that at least one selected from alumina, boron nitride, silicon carbide, diamond, beryllium oxide, aluminum nitride. The method of claim 1, The composite resin composition is a composite resin composition, characterized in that the thermal conductivity is 3W / mk or more. The method of claim 1, The composite resin composition is a composite resin composition, characterized in that the tensile strength of 100 to 200MPa. The method of claim 1, The composite resin composition is a composite resin composition, characterized in that the impact strength is 4KJ / m ² to 8KJ / m ² . The method of claim 1, The composite resin composition is a composite resin composition, characterized in that the bending strength of 140 to 250MPa. The method of claim 1, The composite resin composition is a composite resin composition, characterized in that the flexural modulus is 8000 to 12000 MPa. A display panel displaying an image; A display device covering the display panel, comprising a cover formed of the composite resin composition of claim 1.

Images