KR101781678B1 - Thermally conductive polycarbonate resin composition having good extrudability and molded articles produced therefrom - Google Patents

Abstract

The present invention relates to a thermoconductive polycarbonate resin composition having excellent extrudability and a molded article produced therefrom, and more particularly to a thermoconductive polycarbonate resin composition comprising 50 to 80% by weight of a branched polycarbonate resin; 15 to 40% by weight of a thermally conductive ceramic filler; 1 to 10% by weight of an impact modifier of a core-shell structure; And 1 to 10% by weight of a phosphorus flame retardant; and a molded article produced from the polycarbonate resin composition.
The present invention relates to a thermoconductive polycarbonate resin composition having excellent extrudability and a molded article produced therefrom. More particularly, the present invention relates to a thermoconductive polycarbonate resin composition having excellent heat conductivity, melt strength and elongation, The present invention provides a polycarbonate resin composition and a molded article produced from the polycarbonate resin composition, in which profile extrudability, impact resistance, and flame retardancy are greatly improved without deteriorating other physical properties using rubber.

Description

TECHNICAL FIELD [0001] The present invention relates to a thermoconductive polycarbonate resin composition having excellent extrudability and a molded article produced therefrom. BACKGROUND OF THE INVENTION [0002]

The present invention relates to a thermoconductive polycarbonate resin composition having excellent extrudability and a molded article produced therefrom. More specifically, the present invention relates to a thermoconductive polycarbonate resin composition having excellent thermal conductivity, melt strength and elongation, A polycarbonate resin composition in which profile extrudability, impact resistance and flame retardancy are greatly improved without deteriorating other physical properties, and a molded article produced therefrom.

In general, polymer resins have electrical insulation properties, but they do not efficiently remove heat generated by LEDs with low thermal conductivity (<0.2 W / m · K). Conversely, metals are excellent in heat radiation performance (> 100 W / m · K), but they are difficult to apply to parts requiring electrical insulation due to their electrical conduction characteristics.

However, the linear type polycarbonate resin has been widely used in electronic / electric products due to its excellent mechanical properties, heat resistance, dimensional stability, and moldability. Due to its low melt strength and high temperature elongation, It is not suitable as a material for profile extrusion such as heat sink.

Although a method of adding a large amount of a ceramic filler in order to realize electrical insulation and thermal conductivity in such a linear polycarbonate resin has been devised, there has been a problem that the impact strength, elongation and flame retardancy are deteriorated.

In order to solve the above problems, a method of injecting a metal flame retardant into a linear polycarbonate and a thermally conductive ceramic filler has been disclosed. However, when a small amount of a metal flame retardant is added, an excellent flame retardant property can be realized. However, The strength was reduced.

Therefore, the thermoconductive polycarbonate resin composition produced by the conventional method is applied to electric / electronic products requiring both thermal conductivity and insulation properties such as heat sinks such as LED straight tubes due to low melt strength, elongation, flame retardancy and impact strength There is a limit to things.

KR Patent Publication No. 10-2013-0124930

In order to solve the problems of the prior art as described above, the present invention provides an improved thermoconductivity network that improves thermal conductivity, melt strength, and elongation, and uses a predetermined flame retardant and rubber, , Impact resistance and flame retardancy of the polycarbonate resin composition.

The present invention also aims to provide a molded article produced from the polycarbonate resin composition.

These and other objects of the present disclosure can be achieved by all of the present invention described below.

In order to achieve the above objects, the present invention relates to a resin composition comprising 50 to 80% by weight of a branched polycarbonate resin; 15 to 40% by weight of a thermally conductive ceramic filler; 1 to 10% by weight of an impact modifier of a core-shell structure; And 1 to 10% by weight of a phosphorus flame retardant.

The present invention also provides a molded article produced from the polycarbonate resin composition.

As described above, the present invention relates to a thermoconductive polycarbonate resin composition having excellent extrudability and a molded article produced therefrom. More particularly, the present invention relates to a thermoconductive polycarbonate resin composition having excellent thermal conductivity, melt strength and elongation A polycarbonate resin composition which is improved in profile extrudability, impact resistance and flame retardancy by using a predetermined flame retardant and rubber without deteriorating other physical properties, and a molded article produced therefrom.

FIG. 1 is a photograph of a heat sink, such as an LED straight pipe, made by using the polycarbonate resin composition of the present invention, and a heat sink such as an LED straight pipe made of aluminum together.
Fig. 2 is a photograph of an assembly of a heat sink such as an LED straight pipe made of the polycarbonate resin composition of the present invention and a light diffuser plate made of a PC.
Figs. 3 to 5 are photographs showing the inside and outside of an article, such as an LED straight tube, to which a heat sink such as an LED straight tube manufactured using the polycarbonate resin composition of the present invention is applied.
6 to 8 are SEM photographs of the hexagonal, square and plate-like ceramic fillers of the present invention.

Hereinafter, the present invention will be described in detail.

The polycarbonate resin composition of the present invention comprises 50 to 80% by weight of a branched polycarbonate resin; 15 to 40% by weight of a thermally conductive ceramic filler; 1 to 10% by weight of an impact modifier of a core-shell structure; And 1 to 10% by weight of a phosphorus-based flame retardant.

For example, the branched polycarbonate resin has a melt index (ASTM D1238, 300 DEG C / 1.2 kg) of less than 10 g / 10 min, 9 to 1 g / 10 min, or 2 to 6 g / And has an excellent thermal conductivity, and is suitable for an electric / electronic product which requires heat conductivity and insulation simultaneously such as a heat sink such as an LED straight pipe.

The branched polycarbonate resin may be, for example, 55 to 75% by weight or 58 to 73% by weight, and has a high melt strength and thermal conductivity within this range, and is required to have heat resistance and insulation properties such as heat sinks There is an effect suitable for the manufacture of the profile.

The branched polycarbonate resin may have a weight average molecular weight of 20,000 to 50,000 g / mol, 30,000 to 45,000 g / mol, or 35,000 to 40,000 g / mol, for example.

The branched polycarbonate resin of the present invention refers to, for example, a polycarbonate resin in which a polymer chain is branched by a branching agent introduced during polymerization thereof.

If the branching agent is a substance capable of branching the polymer chain, the branching agent is not limited to the name, and includes, for example, a branching agent or a branching agent.

Examples of the branching agent include 1,1,1-tris (4-hydroxyphenyl) ethane, 4,4- [1- [4- [1- (4- hydroxyphenyl) Ethylidene] bisphenol, phloroglycine, trimellitic acid, trimellitic anhydride, o-cresol, 3,3-bis (3-methyl-4-hydroxyphenyloxy (3-methyl-4-hydroxyphenyl oxyindole), an alkali metal compound or an alkaline earth metal compound.

The branched polycarbonate resin has, for example, a degree of branching of 50% or more, 70% or more, or 90% or more, and has an excellent melt strength and thermal conductivity within this range.

In this description, the degree of branching can be determined by the hydrolysis-HPLC method using the following equation (1).

[Equation 1]

Branching degree (%) = (concentration of branching agent contained in polymer / concentration of BPA) x 100

The thermally conductive ceramic filler may be, for example, 20 to 35% by weight, and has an effect of having high melt strength and thermal conductivity within this range.

The thermally conductive ceramic filler may be at least two kinds selected from the group consisting of a hexagonal ceramic filler, a rectangular ceramic filler and a plate-shaped ceramic filler. The thermally conductive ceramic filler has high melt strength and thermal conductivity within this range.

In the present invention, the hexagonal, rectangular and plate-like shapes of the ceramic filler are not particularly limited in the case of hexagonal, rectangular and plate-like shapes which are generally recognized in this technical field. SEM photographs of hexagonal boron nitride, angled magnesium oxide and plate-like mica are shown in FIGS. 6 to 8, respectively.

The hexagonal ceramic filler may be boron nitride, for example, and has high melt strength and thermal conductivity.

The hexagonal ceramic filler has a particle diameter of 20 to 50 mu m or 25 to 45 mu m and a thermal conductivity of 180 W / m · k or more, 200 W / m · k or 200 to 300 W / m · k And has a high melt strength and thermal conductivity within this range.

In the present description, the particle diameter means a number average particle diameter (average particle diameter (d50) (measured by laser particle size measurement according to ISO 13320 EN).

The rectangular ceramic filler may be, for example, magnesium oxide, and in this case, it is effective to have high melt strength and thermal conductivity.

The rectangular ceramic filler has a particle diameter of 20 to 70 탆 or 40 to 60 탆, for example, and can be surface-treated with a silane compound. In this case, it has an effect of having high melt strength and thermal conductivity.

The silane-based compound may be, for example, aminosilane.

The plate-like ceramic filler can be, for example, talc or mica, and has an effect of having high melt strength and thermal conductivity.

The plate-like ceramic filler may have a particle diameter of 1 to 15 占 퐉 or 2 to 10 占 퐉, for example, and has an effect of having high melt strength and thermal conductivity.

In another example, the thermally conductive ceramic filler is selected from the group consisting of boron nitride; Magnesium oxide; And talc or mica; and preferably at least one selected from the group consisting of boron nitride and magnesium oxide.

The impact modifier of the core-shell structure may be, for example, a silicone-acrylic impact modifier. In this case, not only the impact strength is improved but also the profile extrudability, impact resistance and flame retardancy are improved.

The impact modifier of the core-shell structure may be a silicone-vinyl-based core-shell structure, for example.

The impact modifier of the core-shell structure may be, for example, a copolymer of poly (dialkylsiloxane), alkyl methacrylate and alkyl acrylate.

The poly (dialkylsiloxane) may be, for example, poly (dimethylsiloxane), and the alkyl methacrylate may be, for example, methyl methacrylate, and the alkyl acrylate may be, for example, butyl acrylate.

The impact modifier of the core-shell structure may be, for example, 1 to 8% by weight, or 2 to 4% by weight. Within this range, impact strength is improved, and excellent effects on profile extrusion, impact resistance and flame retardancy .

The phosphorus flame retardant may be, for example, a phosphoric acid ester flame retardant. In this case, not only the flame retardancy is improved but also the profile extrudability and impact resistance are excellent.

The phosphorus flame retardant may be, for example, 5 to 20% by weight or 8 to 15% by weight.

The phosphorus flame retardant may be, for example, 1 to 6% by weight or 2 to 5% by weight, and has an excellent flame retardancy and excellent profile extrudability and impact resistance.

The polycarbonate resin composition may further include 0 to 5% by weight of a dispersant based on 100 parts by weight of a total of 100 parts by weight of a branched polycarbonate resin, a thermally conductive ceramic filler, a core-shell structure impact modifier and a phosphorus- It is possible to improve the wettability with the resin and reduce the thermal resistance between the fillers to form an optimal thermal conductivity network, thereby achieving a sufficient thermal conductivity with the minimum amount of the thermally conductive ceramic filler, and also securing excellent melt strength and elongation have.

The dispersing agent is not particularly limited when it is a dispersing agent capable of dispersing the pigment and the inorganic filler. The dispersing agent is preferably a copolymer having a pigment affinic group. In this case, It is possible to form an optimal thermal conductivity network by reducing the thermal resistance between the thermally conductive ceramic filler and the thermally conductive ceramic filler, thereby achieving the thermal conductivity with the minimum amount of the thermally conductive ceramic filler and securing excellent melt strength and elongation.

The pigment-affinity group may be at least one selected from the group consisting of a hydroxyl group, a carboxyl group and an amine group.

The dispersant may be at least one selected from the group consisting of a polyester dispersant, a polyacrylic dispersant, and a polyurethane dispersant.

In general, the dispersant increases the dispersing power by a pigment-affinity generating electrostatic repulsion force and maintains the distance between the components by the non-polar polymer chain that exhibits the effect of the hindered effect, thereby preventing the components from aggregating or biasing.

The dispersant may be, for example, 0.1 to 3% by weight, or 0.5 to 1.0% by weight. Within this range, the wettability with the resin and the thermal resistance between the fillers are reduced to form an optimal thermal conductivity network, The ceramic filler can realize thermal conductivity, and excellent melt strength and elongation can be secured.

For example, the polycarbonate resin composition may have a thermal conductivity of 1.5 W / m · k or more, or 1.5 to 2.5 W / m · k, and a thermally conductive material applied to a heat sink, such as an LED straight tube, have.

The polycarbonate resin composition may have a melt strength (N, Rheotens, 250 DEG C) of 0.12 or more, or 0.12 to 0.19, and is suitable as a thermally conductive material applied to a heat sink such as an LED straight tube within this range .

For example, the polycarbonate resin composition may have an impact strength (ASTM D238) of 90 J / m or more, or 90 to 150 J / m, and a thermally conductive material .

The polycarbonate resin composition may have an elongation (ASTM D638) of 5.5% or more, or 5.5 to 11.0%, and is suitable as a thermally conductive material applied to a profile requiring both thermal conductivity and insulation within the range .

The molded article of the present invention is characterized by being produced from the polycarbonate resin composition of the present invention.

The molded article may be, for example, a thermally conductive profile.

The thermally conductive profile may be, for example, a LED lighting fixture.

The illumination lamp may be, for example, an intuition tube.

1 to 5 show a heat sink such as an LED straight pipe manufactured from the polycarbonate resin composition of the present invention, and a finished product such as an LED straight pipe including the heat sink.

It will be apparent to those skilled in the art that various modifications and variations can be made in the present invention within the scope and spirit of the following claims, Such variations and modifications are intended to be within the scope of the appended claims.

[Example]

The components used in the production of the following polycarbonate resin composition are as follows.

(A) Linear Type Polycarbonate (L-PC)

A linear aromatic polycarbonate having a melt index of 10 g / 10 min (A-1) and 3 g / min (A-2) at 300 ° C / 1.2 Kg was used as a polymer of bisphenol A based on ASTM D1238.

(B) Branched Type Polycarbonate (B-PC)

Branched polycarbonate resin (1,1,1-tris (4-hydroxyphenyl) ethane as a branching agent and having a melt index of 3 g / 10 min at 300 DEG C / 1.2 Kg and a branching degree of 100% according to ASTM D1238 Ltd.) was used.

(C) boron nitride

Boron nitride having a size of 25 to 45 μm and a thermal conductivity of 200 W / m · K or more was used.

(D) Magnesium oxide

Magnesium oxide surface-treated with a silane-based compound having a size of 50 mu m by UBE was used.

(E) a plate-like inorganic particle of talc

KOCH's size 3 ~ 7㎛, components Mg ₆ (Si ₄ O ₁₀₎ was used as a ₂ (OH) _4.

(F) Impact reinforcement of core-shell structure

MRC's silicon-acrylic impact modifier (METABLEN S-2001), which is a silicon-vinyl based core-shell structure, was used.

(G) Phosphorous flame retardant

PX-200 manufactured by Daihachi Co., Ltd. was used.

(H) Metal salt flame retardant

An RM 65 product consisting of Potassium Perfluorobutane sulfonate (C4F9O3K) component from MITENI Co. was used.

(I) Dispersant for inorganic filler

Dispersant composed of BYK Copolymer with pigment affinic groups was used.

Examples 1 to 8 and Comparative Examples 1 to 6

Polycarbonate resin, magnesium oxide, and talc were charged into the main hopper of the twin-screw extruder at the composition ratios shown in Tables 1 and 2 below, and boron nitride was added to the side of the extruder. The mixture was melt-kneaded at 290 ° C. and 250 rpm And extruded to produce pellets.

Polycarbonate resin specimens were prepared by injection molding the pellets at 80 ~ 100 ℃.

Comparative Example 7

A polycarbonate resin specimen was prepared in the same manner as in Example 1 except that the linear polycarbonate (A-2) was used in place of the branched polycarbonate (B-PC) in Example 1.

[Test Example]

The properties of the polycarbonate resin composition specimens prepared in Examples 1 to 8 and Comparative Examples 1 to 7 were measured by the following methods, and the results are shown in Tables 1 and 2 below.

Thermal conductivity (W / m 占)): Measured according to ASTM E1461.

Surface resistance (Ohm): Measured according to IEC 60093.

* Melt strength (N): Measured at 250 ° C using Rheotens (Goettfert.

Tensile strength (MPa): Measured according to ASTM D638.

Elongation (%): Measured according to ASTM D638.

Impact strength (J / m): Measured according to ASTM D238.

Flexural modulus (MPa): Measured according to ASTM D790.

* Flammability: Measured according to UL94V.

* Branching degree: calculated by hydrolysis-HPLC method (Hewlett-Packard Molel 1,100 and DAD detector) using the following equation (1).

[Equation 1]

Branching degree (%) = (1,1,1-tris (4-hydroxyphenyl) ethane concentration / BPA concentration) x 100

The hydrolysis was carried out using methanol and 30% sodium methoxide in a ratio of 3: 1 (volume ratio).

Comparative Example Example One 2 3 4 One 2 3 4 A-1 65 A-2 65 65 B 62 60 58 63 63 C 5 D 30 30 5 30 30 30 25 25 E 5 5 30 5 5 5 5 F 2 4 4 4 G 3 3 3 3 3 H 0.2 0.2 0.2 I 0.6 0.6 Thermal conductivity 1.4 1.4 1.8 1.4 1.7 1.7 2.0 2.2 Surface resistance > 10 ¹⁴ > 10 ¹⁴ > 10 ¹⁴ > 10 ¹⁴ > 10 ¹⁴ > 10 ¹⁴ > 10 ¹⁴ > 10 ¹⁴ Melt strength 0.01 0.04 0.02 0.06 0.12 0.15 0.17 0.18 Impact strength 36 45 27 30 110 135 150 140 The tensile strength 46 46 55 46 43 40 42 41 Elongation 2.0 3.0 1.4 2.5 7.2 9.0 11.0 10.0 Flexural modulus 4,456 4,450 4,970 4,460 3,650 3,420 3,850 3,700 Flammability HB HB HB V-1 V-1 V-1 V-0 V-0

As shown in Table 1, the polycarbonate resin compositions (Examples 1 to 4) of the present invention had insulating properties (surface resistance) as compared with the case where the impact modifier and the like according to the present invention were not included (Comparative Examples 1 to 4) , The tensile strength, the flexural modulus and the like were maintained at the same level, but the thermal conductivity, impact strength, melt strength and elongation were remarkably excellent. Further, it can be confirmed that the excellent melt strength and elongation are suitable as a material for profile extrusion.

Comparative Example Example 5 6 7 5 6 7 8 A-1 A-2 80 80 60 B 73 73 68 68 C 10 10 10 10 10 10 D 10 30 10 5 5 E 10 5 10 10 10 F 2 4 4 4 4 G 3 3 3 3 3 H 0.2 0.2 I 0.6 Thermal conductivity 1.8 1.5 1.7 1.8 1.5 2.0 2.5 Surface resistance > 10 ¹⁴ > 10 ¹⁴ > 10 ¹⁴ > 10 ¹⁴ > 10 ¹⁴ > 10 ¹⁴ > 10 ¹⁴ Melt strength 0.03 0.02 0.04 0.18 0.18 0.16 0.19 Impact strength 40 35 90 160 120 98 120 The tensile strength 50 49 45 50 55 56 60 Elongation 5.2 3.8 5.0 10.0 8.5 5.5 7.5 Flexural modulus 3,650 4,350 3,550 3,650 4,370 4,500 5,200 Flammability HB HB V-1 V-0 V-0 V-0 V-0

As shown in the above Table 2, the polycarbonate resin compositions (Examples 5 to 8) of the present invention had insulating properties (surface roughness) as compared with the case where the impact modifier according to the present invention was not included (Comparative Examples 1 to 3 and 7) Resistance, tensile strength, flexural modulus and the like were maintained at the same level, but the thermal conductivity, impact strength, melt strength and elongation were remarkably excellent. Further, it can be confirmed that the excellent melt strength and elongation are suitable as a material for profile extrusion.

Further, it was confirmed that the thermal conductivity, the melt strength, the impact strength, the elongation and the flexural modulus of the polycarbonate resin composition of the present invention were significantly improved when the dispersant according to the present invention was further contained (Examples 3, 4 and 8) .

Claims (19)

50 to 80% by weight of a branched polycarbonate resin; 15 to 40% by weight of a thermally conductive ceramic filler; 1 to 10% by weight of an impact modifier of a core-shell structure; 1 to 10% by weight of a phosphorus flame retardant; And 0.1 to 3% by weight of a dispersing agent,
Wherein the degree of branching of the branched polycarbonate resin is 70% or more, and the dispersant is at least one selected from a polyester dispersant, a polyacrylic dispersant, and a polyurethane dispersant
Polycarbonate resin composition. delete The method according to claim 1,
Wherein the branched polycarbonate resin has a melt index (ASTM D1238, 300 DEG C / 1.2 kg) of less than 10 g / 10 min
Polycarbonate resin composition. The method according to claim 1,
Wherein the thermally conductive ceramic filler is at least two selected from the group consisting of a hexagonal ceramic filler, a rectangular ceramic filler, and a plate-shaped ceramic filler
Polycarbonate resin composition. 5. The method of claim 4,
Characterized in that the hexagonal ceramic filler is boron nitride
Polycarbonate resin composition. 5. The method of claim 4,
Wherein the hexagonal ceramic filler has a particle diameter of 20 to 50 占 퐉 and a thermal conductivity of 180 W / m 占 k or more
Polycarbonate resin composition. 5. The method of claim 4,
Wherein the rectangular ceramic filler is magnesium oxide
Polycarbonate resin composition. 5. The method of claim 4,
Wherein the rectangular ceramic filler has a particle diameter of 20 to 70 탆 and is surface-treated with a silane-based compound
Polycarbonate resin composition. 5. The method of claim 4,
Characterized in that the plate-like ceramic filler is talc or mica
Polycarbonate resin composition. 5. The method of claim 4,
Wherein the plate-like ceramic filler has a particle diameter of 1 to 15 mu m
Polycarbonate resin composition. The method according to claim 1,
Wherein the impact modifier of the core-shell structure is a silicone-acrylic impact modifier
Polycarbonate resin composition. The method according to claim 1,
Characterized in that the phosphorus flame retardant is a phosphate ester flame retardant
Polycarbonate resin composition. The method according to claim 1,
Wherein the dispersing agent is a copolymer having a pigment affinic group
Polycarbonate resin composition. The method according to claim 1,
Wherein the polycarbonate resin composition has a thermal conductivity of 1.5 W / m · k or more
Polycarbonate resin composition. The method according to claim 1,
Wherein the polycarbonate resin composition has a melt strength (N, Rheotens, 250 DEG C) of at least 0.12
Polycarbonate resin composition. The method according to claim 1,
Wherein the polycarbonate resin composition has an impact strength (ASTM D238) of 90 J / m or more
Polycarbonate resin composition. The method according to claim 1,
The polycarbonate resin composition is characterized in that the elongation (ASTM D638) is 5.5% or more
Polycarbonate resin composition. A polycarbonate resin composition prepared from the polycarbonate resin composition of any one of claims 1 to 17
Shaped article. 19. The method of claim 18,
Wherein the molded article is a thermally conductive profile
Shaped article.

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