KR101256261B1 - Polycarbonate resin composition and article prepared using the same - Google Patents

Abstract

It contains 0.1-20 weight part of inorganic fillers with respect to 100 weight part of base resin which consists of 40 to 90 weight% of polycarbonate resin, 1 to 30 weight% of a styrene-type copolymer, and 1 to 30 weight% of a rubber-styrene graft copolymer. The inorganic filler is a polycarbonate resin composed of 10 to 90% by weight of an inorganic filler having an average particle diameter (d ₅₀ ) of 1 to 4 µm and 90 to 10% by weight of an inorganic filler having an average particle diameter (d ₅₀ ) of 7 to 20 µm. A composition and a molded article using the same are provided. Such a polycarbonate resin composition is excellent in mechanical rigidity, impact resistance and dimensional stability.

Polycarbonate, ABS resin, inorganic filler, talc, mica

Description

Polycarbonate resin composition and article prepared using the same

The present specification describes a polycarbonate resin composition and a molded article using the same.

Since polycarbonate resins have excellent heat resistance and strength, particularly impact strength and transparency, they are widely used as electrical parts, mechanical parts, and industrial resins.

In their widespread use, especially when applied as metal substitutes, such as in automobiles, there is a need to improve the stiffness and reduce the degree of thermal expansion while maintaining good ductility and fluidity.

It is known to add inorganic fillers such as talc or mica to increase the stiffness in polycarbonates.

One aspect of the embodiments of the present invention is to provide a polycarbonate resin composition and a molded article using the same having high rigidity and high impact resistance even when the inorganic filler is added to the polycarbonate composition.

Another aspect of embodiments of the present invention is excellent in dimensional stability with workability that can induce a regular orientation in the resin composition of the inorganic filler in the case of adding an inorganic additive to the polycarbonate composition to maintain a constant injection rate and thus An object of the present invention is to provide a polycarbonate resin composition suitable for a molded article requiring high dimensional precision and a molded article using the same.

Another aspect of embodiments of the present invention is to provide a polycarbonate resin composition excellent in heat resistance, thermal stability, flame retardancy and appearance properties and molded articles using the same.

In embodiments of the present invention, 40 to 90% by weight of a polycarbonate resin; 1 to 30% by weight of a styrenic copolymer; And 0.1 to 20 parts by weight of an inorganic filler, based on 100 parts by weight of the base resin consisting of 1 to 30% by weight of a rubber-styrene graft copolymer, wherein the inorganic filler has an average particle diameter (d ₅₀ ) of 1 to 4 μm. an inorganic filler of 10 to 90% by weight and an average particle diameter (d ₅₀₎ provides a polycarbonate resin composition comprising the 7 ~ 20㎛ the inorganic filler to 90 to 10% by weight.

Another embodiment of the present invention provides a molded article made of the polycarbonate resin composition.

The polycarbonate resin composition according to the embodiments of the present invention contains an inorganic filler but combines the inorganic filler average particle diameter to achieve excellent mechanical strength (stiffness), impact resistance and dimensional stability, as well as in the injection flow direction. The uniformity of impact strength on the surface can be improved. In addition, the polycarbonate resin composition may exhibit improved properties in appearance characteristics along with heat resistance, heat stability, and flame retardancy.

Such a polycarbonate resin composition can be suitably used for molding various parts such as molded articles (particularly molded articles by injection), for example, electronic material housings and automobile frames that require high rigidity, high impact resistance, flame retardancy, and high dimensional accuracy.

Hereinafter, exemplary embodiments of the present invention will be described.

Inorganic fillers may be added to the polycarbonate composition or blend to increase the stiffness, but our research results indicate that mechanical or physical properties are limited due to the addition of the inorganic filler itself.

Surprisingly, however, when inorganic fillers, in particular talc or mica, are contained in the polycarbonate composition, by varying and filling the particle size of the inorganic filler, not only can provide improved rigidity and impact resistance than the existing polycarbonate blend, but also good In addition to the dimensional accuracy, excellent appearance characteristics can be exhibited.

This is because inorganic materials having a particle size diversified than a single type of inorganic materials induce regular orientation in the resin composition, thereby improving the dimensional stability of the resin composition, improving the uniformity of the impact strength in the injection flow direction, and improving the stiffness and impact resistance characteristics. It is thought to bring.

In embodiments of the present invention, the polycarbonate resin, the styrene-based copolymer resin, the rubber-styrene graft copolymer to form as a base resin of the thermosetting resin composition, and as an inorganic filler, the average particle diameter (d ₅₀ ) 1 At least 10 wt% or more (10 to 90 wt%) of the inorganic filler (“fine inorganic filler”) of 4 μm in average particle diameter (d ₅₀ ) Inorganic filler (“giant inorganic filler”) of 7 to 20 μm Blend at least 10% by weight or more (10-90% by weight).

In embodiments of the present invention, the polycarbonate resin, the styrenic copolymer resin and the rubber-styrene graft copolymer resin contained in the base resin have improved mechanical properties, impact resistance, and dimensional accuracy when inorganic fillers of varying average particle diameters are added. (Dimension stability) and the like are components selected to be suitable for achieving improved uniformity of impact strength with respect to the injection flow direction.

In a non-limiting example, preferably the base resin consists of 40 to 90 weight percent polycarbonate, 1 to 30 weight percent styrenic copolymer and 1 to 30 weight percent rubber-styrene graft copolymer.

In embodiments of the present invention, it is also preferable to further add a phosphorus-based flame retardant to the base resin in order to improve the flame retardancy.

By adding an inorganic filler having a diversified average particle diameter to such a base resin and additionally a phosphorus-based flame retardant, a molded article requiring high rigidity, high impact resistance and high dimensional precision can be produced. In addition, despite the inclusion of the inorganic filler, the wear of the mold is low, the uniformity of the impact strength in the injection flow direction is improved, and the injection speed can be kept constant during molding by injection, thereby improving workability. . In addition, good flame retardant properties can be achieved with a relatively small amount of flame retardant.

Such a resin composition is very suitable for molding various parts such as rigidity, impact resistance, dimensional accuracy, flame retardancy, etc., such as electronic material housings, frames, and the like.

Specifically, each component is described as follows.

(a) thermoplastic aromatic polycarbonate

In embodiments of the present invention, the thermoplastic aromatic polycarbonate resin is contained in the base resin.

In an exemplary embodiment, the thermoplastic aromatic polycarbonate resin may be prepared from a dihydric phenol, a carbonate precursor, a molecular weight modifier to control the molecular weight, and the like.

The dihydric phenols may be any substance derived from the structure of the following [Formula 1].

In Formula 1, X includes an alkyl group, a sulfide, an ether, a sulfoxide, a sulfone, a ketone, or the like without any functional groups. Preferably X represents a straight, branched or cyclic alkyl group, more preferably X represents a straight, branched or cyclic alkyl group containing 1 to 10 carbons. R ₁ and R ₂ represent hydrogen, a halogen atom, a straight, branched or cyclic alkyl group. On the other hand, n and m can independently select an integer of 0 to 4.

Non-limiting examples of the dihydric phenols include bis (4-hydroxyphenyl) methane, bis (4-hydroxyphenyl) phenylmethane, bis (4-hydroxyphenyl) naphthylmethane, bis (4-hydroxy Phenyl)-(4-isobutylphenyl) methane, 1,1-bis (4-hydroxyphenyl) ethane, 1-ethyl-1,1-bis (4-hydroxyphenyl) propane, 1-phenyl-1, 1-bis (4-hydroxyphenyl) ethane, 1-naphthyl-1,1-bis (4-hydroxyphenyl) ethane, 1,2-bis (4-hydroxyphenyl) ethane, 1,10-bis (4-hydroxyphenyl) decane, 2-methyl-1,1-bis (4-hydroxyphenyl) propane, 2,2-bis (4-hydroxyphenyl) propane (bisphenol A) and the like. Representative of these is bisphenol A.

It is preferable to apply phosgene (carbonyl chloride) as said carbonate precursor as another monomer of polycarbonate resin.

Non-limiting examples of such carbonate precursors include carbonyl bromide, bis halo formate, diphenyl carbonate or dimethyl carbonate and the like.

The molecular weight modifier may use a monofunctional compound similar to the materials already known, that is, the monomers used to prepare the thermoplastic aromatic polycarbonate resin.

By way of non-limiting example, derivatives based on phenols (e.g., para-isopropylphenol, para-tert-butylphenol, para-cumylphenol, para-isooctylphenol, para-isononylphenol, etc.) In addition, various kinds of substances such as aliphatic alcohols may be used, and among them, para-tert-butylphenol (PTBP) is most preferably applied.

As an aromatic polycarbonate resin prepared from such a dihydric phenol, a carbonate precursor, a molecular weight modifier, for example, a linear polycarbonate resin, a branched polycarbonate resin, a copolycarbonate resin, a polyester carbonate resin, or the like There is this.

In embodiments of the present invention, it is suitable for the polycarbonate resin to comprise in particular branched polycarbonate resin. Branched polycarbonate resins are advantageous for achieving better flame retardancy and reducing the tendency of the specimen to drip during flame retardant tests due to the excellent melt strength and morphological stability of the resin itself.

The branched polycarbonate resin is preferably mixed at 10 to 50% by weight in the total aromatic polycarbonate resin. If the content of branched polycarbonate is less than 10% by weight, the anti-dripping effect may be insignificant in the flame retardant test, and if it exceeds 50% by weight, the melt viscosity may be increased, causing problems in resin processing. have.

On the other hand, in the exemplary embodiments of the present invention, the thermoplastic aromatic polycarbonate resin, it is preferable to apply that the viscosity average molecular weight (M _v ) measured in the methylene chloride solution is 17,000 to 40,000, of 20,000 to 30,000 It is more preferable to make it apply.

When the average molecular weight is less than 17,000, mechanical properties such as impact strength and tensile strength may be greatly reduced, and when the average molecular weight exceeds 40,000, problems may occur in processing of the resin due to an increase in melt viscosity.

Such polycarbonate resin is to be used in 40 to 90% by weight of the base resin composition, preferably to use 80 to 90% by weight. When the polycarbonate content is 40% by weight or less, mechanical properties such as heat resistance and flexural strength may be greatly reduced. When the polycarbonate content is more than 90% by weight, impact strength may be greatly reduced and melt viscosity may be increased, thereby causing problems in injection molding. have.

(b) Styrene series  Copolymer

In embodiments of the present invention, the styrenic copolymer resin is contained in the base resin.

In an exemplary embodiment, the styrenic copolymer resin is (i) 50-95% by weight of styrene, α-methylstyrene, halogen or alkyl substituted styrene or mixtures thereof and (ii) acrylonitrile, methacrylonitrile, Styrene copolymer obtained by copolymerizing C 1 -C 8 methacrylic acid alkyl esters, C 1 -C 8 acrylic acid alkyl esters, maleic anhydride, C 1 -C 4 alkyl or phenyl N-substituted maleade or a mixture thereof 50 to 5% by weight or Mixtures of these can be used. When the content of C1-C4 alkyl or the like or a mixture thereof is 5% by weight or less, the effect of adding the styrene copolymer may be lost. When the content is 50% by weight or more, mechanical properties such as impact strength and tensile strength are greatly increased. Can be degraded.

C1-C8 methacrylic acid alkyl esters or C1-C8 acrylic acid alkyl esters used in the production of the styrene copolymer resin are monohydryls each containing 1 to 8 carbon atoms as esters of methacrylic acid or acrylic acid, respectively. Esters obtained from alcohols. Non-limiting examples thereof include methacrylic acid methyl ester, methacrylic acid ethyl ester, acrylic acid ethyl ester or methacrylic acid propyl ester.

In embodiments of the invention, preferred examples of styrenic copolymer resins are those prepared from monomer mixtures of styrene and acrylonitrile and optionally methacrylic acid methylester, or α-methylstyrene and acrylonitrile and optional And those prepared from monomer mixtures of methacrylic acid methyl esters.

The styrene / acrylonitrile copolymer may be prepared by emulsion polymerization, suspension polymerization, solution polymerization, or bulk polymerization, and a weight average molecular weight of 15,000 to 300,000 is preferably used. When the average molecular weight of the styrene-based copolymer resin is 15,000 or less, mechanical properties such as impact strength and tensile strength may be greatly reduced. When the average molecular weight exceeds 300,000, problems may occur in processing of the resin due to an increase in melt viscosity. Can be.

In the embodiments of the present invention, the styrenic copolymer resin may be used alone or in the form of a mixture of two or more thereof, and is used in the range of 1 to 30% by weight of the base resin. When the content of the styrene copolymer resin is less than 1% by weight, the impact resistance may be improved, and when the content is more than 30% by weight, mechanical properties such as flexural modulus and heat resistance may be drastically lowered. May occur.

For reference, the thermoplastic styrene-based copolymer resin may be produced as a by-product in the preparation of the rubber-modified vinyl-based graft copolymer described below. In particular, it is possible to produce more when grafting an excess monomer mixture to a small amount of rubbery polymer or when an excessive amount of a chain transfer agent used as a molecular weight control agent is used. In the embodiments of the present invention, the content of the styrene-based copolymer resin in the base resin is not shown including the by-product of the rubber-modified vinyl-based graft copolymer as described above.

(c) rubber-styrene Graft  Copolymer

In embodiments of the present invention, the rubber-modified vinyl-based graft copolymer is contained in the base resin.

In an exemplary embodiment, the rubber modified vinyl graft copolymer comprises 50 to 95 weight percent of styrene, α-methylstyrene, halogen or alkyl substituted styrene, or mixtures thereof; And acrylonitrile, methacrylonitrile, C1-C8 methacrylic acid alkyl esters, C1-C8 acrylic acid alkyl esters, maleic anhydride, C1-C8 alkyl or phenyl N-substituted maleimides, or mixtures thereof. 5% to 95% by weight of the monomer mixture (C.1) consisting of butadiene rubber, acrylic rubber, ethylene / propylene rubber, styrene / butadiene rubber, acrylonitrile / butadiene rubber, isoprene rubber, and ethylene-propylene-diene It can be obtained by graft copolymerization to 5 to 95% by weight of at least one rubbery polymer (C.2) selected from the group consisting of terpolymer (EPDM) and polyorganosiloxane / polyalkyl (meth) acrylate rubber composites.

The C1-C8 methacrylic acid alkyl esters or C1-C8 acrylic acid alkyl esters used in the rubber-modified vinyl graft copolymer preparation are monoesters containing 1 to 8 carbon atoms as esters of methacrylic acid or acrylic acid, respectively. Ester obtained from hydryl alcohol.

In embodiments of the present invention, the average particle diameter (d ₅₀ ) of the rubbery polymer (C.2) is preferably used in the 0.05 ~ 4 ㎛ to improve the impact strength and the surface properties of the molding. Here, the average particle diameter d ₅₀ refers to the diameter in which 50% of the particles exist above and below the value. It is an ultra-centrifuge assay (eg, W. Scholtan et al. Kolloid-Z. und Z. Polymere 250 (1972), p. 782 to 796].

When the average particle diameter (d ₅₀ ) of the rubbery polymer is less than 0.05㎛ If the impact resistance and mechanical properties are insignificant, it may be difficult to expect the effect of introducing the rubbery filler, and if it exceeds 4 μm, Due to the deterioration of dispersibility and cohesiveness, even surface characteristics may not be expected and thermal deformation temperature and mechanical properties may be reduced.

The rubber-modified vinyl graft copolymer may be prepared by a known method, and the production method is well known. For example, the rubber-modified vinyl graft copolymer may be prepared by emulsion polymerization, suspension polymerization, solution polymerization, bulk polymerization, and the like.

The compounding amount of the rubber-modified vinyl-based graft copolymer used in the resin composition according to the embodiments of the present invention is 1 to 30% by weight, preferably 2 to 10% by weight. When the content of the rubber-modified vinyl graft copolymer is less than 1% by weight, the impact resistance may be insignificant, and when the content is more than 30% by weight, other mechanical properties such as heat resistance and surface formability may be considerably reduced. Problems may arise.

Weapon filler ( inorganic filler ; weapon Filling )

Inorganic materials may be added to the polycarbonate composition, in particular inorganic materials which increase melt stability due to thixotropic effects and improve the flame retardancy of the molding composition. The inorganic material is used in an amount which is as small as possible but effective and which may have a positive or at least no negative effect on the mechanical properties of the material.

In the exemplary embodiments of the present invention, the inorganic material used as the inorganic filler is not particularly limited, but as described below, the inorganic material having a dual particle size distribution is used.

The inorganic material may be, for example, particulate, flaked or fibrous. As a non-limiting example, mica, quartz powder, titanium dioxide, silicates, aluminosilicates can be used. Also, for example chalk, wollastonite, mica lamellar clay minerals, montmorillonite, especially montmorillonite in the form of ion exchange modified liporgano, talc, kaolin, zeolite, vermiculite, aluminum oxide, silica, magnesium hydroxide, aluminum hydroxide, glass fibers, Glass flakes and the like can be used. Mixtures of different inorganic materials can also be used.

In the embodiments of the present invention, talc or mica is particularly preferable for the polycarbonate resin composition.

The pure chemical composition of the mica is 3MgO.4SiO2.H2O, 31.9 wt% MgO content, 63.4 wt% SiO2 content and 4.7 wt% chemically bound water content. This is a silicate having a layered structure.

In an exemplary embodiment, the polycarbonate resin composition contains 0.1 to 20 parts by weight of the inorganic filler based on 100 parts by weight of the base resin. Further, as the inorganic filler, the average particle diameter (d ₅₀₎ is used 1 ~ 4㎛ an inorganic filler mixture of 10-90% by weight, average particle size (d ₅₀₎ size of 90 to 10% by weight of 7 ~ 20㎛.

Also be used as the average particle diameter (d ₅₀₎ The more preferred range of 1 to a more preferable range of the average particle diameter of 1 to 4㎛ _{3㎛, (d 50) 7 ~} 20㎛ that the 9 ~ 15㎛ particularly advantageous .

In a non-limiting example, preferably 30 to 70% by weight of the inorganic filler having an average particle diameter (d ₅₀ ) of 1 to 4 μm (preferably 1 to 3 μm) and an average particle diameter (d ₅₀ ) of 7 to the inorganic filler. 70 to 30% by weight of 20 µm (preferably 9 to 15 µm) is mixed.

Here, as described above, the average particle diameter d ₅₀ refers to a diameter in which 50% of particles exist above and below the value, and the ultra-centrifuge measurement method (for example, W. Scholtan) Et al., Kolloid-Z. und Z. Polymere 250 (1972), p. 782 to 796].

In the embodiments of the present invention, by mixing the inorganic filler, by combining the average particle diameter of the inorganic filler by dual, it is possible to satisfy various mechanical properties evenly. By dualizing the average particle diameter of such inorganic filler particles, it is possible to provide an excellent resin composition having excellent mechanical properties as well as improved workability than when the inorganic filler having a single particle size distribution is added. In the present specification, dualization means mixing an inorganic filler having a fine particle size and an inorganic filler having a large particle size, mixing at least 10 wt% or more of the inorganic filler with a fine particle size, and mixing an inorganic filler having a large particle size with at least 10 of the inorganic filler. Mixing by weight or more is defined as binaryization.

Specifically, when only the inorganic filler having an average particle diameter (d ₅₀ ) of 1 to 4 µm is introduced, there are advantages in the surface properties and impact strength of the resin, but in terms of rigidity, only the inorganic filler having an average particle diameter (d ₅₀ ) of 7 to 20 µm is used. There may be a loss compared to the injected resin.

On the contrary, when only the inorganic filler having an average particle diameter (d ₅₀ ) of 7 to 20 µm is added, the rigidity is very high, but the surface characteristics and impact strength of the resin may be relatively poor.

Therefore, in the embodiments of the present invention, the average particle diameter of the inorganic filler is dualized and introduced at a predetermined ratio, in order to benefit all the properties of the mechanical properties such as the surface properties, stiffness, and impact resistance of the resin, thereby having excellent mechanical properties. It is possible to provide a polycarbonate resin composition having improved impact properties, dimensional stability and mechanical strength, and improved surface properties.

In the above aspect, talc or mica is particularly suitably used as the inorganic filler in the embodiments of the present invention.

Flame retardant

The resin composition according to the embodiments of the present invention further includes a flame retardant.

In an exemplary embodiment, the flame retardant is a phosphate ester compound.

In a non-limiting example, the phosphate ester compound is preferably a phosphate ester compound of [Formula 2].

In [Formula 2], R ₁ , R ₂ , R ₃ and R ₄ are each independently of each other, optionally halogenated C ₁ -C ₈ C ₅ -C ₆ cycloalkyl, C ₆ -C ₂₀ aryl or C ₇ -C ₂₀ aralkyl which may be alkyl or preferably optionally substituted with C ₁ -C ₄ alkyl or halogen, preferably chlorine or bromine, respectively to be. Particularly preferred aryl groups are cresyl, phenyl, xylenyl, propylfetyl or butylphenyl and their corresponding brominated derivatives, chlorinated derivatives.

In Formula 2, n may be 0 or 1 independently of each other, and preferably 1. In said Formula 2, N is 0-10 as an average value, Preferably it is 0.3-8, More preferably, it is 0.5-5.

X in [Formula 2] is a mononuclear aromatic or polynuclear aromatic group having 6 to 30 carbon atoms, which may be derived from diphenylphenol, bisphenol A, resorcinol or hydroquinone, or chlorinated or brominated derivatives thereof.

As the phosphate ester compound used in the embodiments of the present invention, monophosphate (N = 0), oligophosphate (average value in the range of N = 1-10) or a mixture of monophosphate and oligophosphate may be used.

In a non-limiting example, preferred examples of phosphate ester compounds are selected from resorcinol bis (diphenyl phosphate), bisphenol-A bis (diphenyl phosphate), resorcinol bis (di 2,6-dimethylphenyl phosphate) It may include one or more.

In embodiments of the present invention, the phosphate ester compound is used in 1 to 20 parts by weight based on 100 parts by weight of the base resin. If it is less than 1 part by weight, the flame retardancy is poor, and if it is more than 20 parts by weight, mechanical strength and heat resistance may be deteriorated due to deterioration in mechanical properties.

The polycarbonate resin composition according to the embodiments of the present invention may be used in addition to the above-described components in addition to the usual additives such as heat stabilizers, mold release agents, antioxidants, light stabilizers, ultraviolet absorbers, pigments or dyes, depending on the use.

The polycarbonate resin composition as described above can be produced as a molded article by a known molding method such as injection. Such molded products may exhibit high rigidity, high impact resistance, high dimensional accuracy, good flame retardancy, and the like, and thus include, for example, housings of small-scale high-tech IT equipment such as laptops and mobile phones, and frames of devices having optical system units such as printers, copiers, and projector devices. It can be usefully used in the back.

Hereinafter, one or more exemplary embodiments of the present invention will be described in more detail through non-limiting and exemplary embodiments.

[Physical test of Examples 1-3 and Comparative Examples 1-2]

In order to examine the effect of the input of the dualized inorganic fillers (the use of talc in this example and the comparative example) on the mechanical properties, surface properties, etc., the following examples and comparative examples were constructed, Shrinkage, surface properties, and flame retardant properties were evaluated.

The compositions of Examples 1 to 3 and Comparative Examples 1 and 2 were prepared in the proportions shown in the following [Table 1]. Each component was premixed together in a high speed mixer with the corresponding composition and then mixed in an 270 ° C. extruder. The compositions were then molded as shown above.

The physical properties were measured according to the standard as described below, and the apparent surface properties were measured by the method specified using the microscope equipment.

Property measurement

Flexural modulus, heat deflection temperature, impact resistance, mold shrinkage, and the like of the compositions of Examples and Comparative Examples were tested. The details of these tests used in the examples are known to those skilled in the art and can be summarized as follows:

Flexural modulus:

Flexural modulus was measured according to ASTMD-790. (Test Specimen Dimensions: Length 127mm x Width 12.7mm x Thickness 6.4mm)

Impact resistance (notched Izod impact strength):

Impact resistance was measured according to ASTM D-256. It was determined using molded Izod Notched Strength (INI) bars of 4 mm thickness. The joule energy used to break a specimen is defined as the value divided by the specimen area at the notch. The results are measured in kgfcm / cm.

Heat Deflection Temperature:

The load deflection temperature with increasing temperature was measured according to ASTM D-648. (Test Specimen Dimensions: Length 127mm x Width 12.7mm x Thickness 6.4mm)

Mold Shrinkage:

The specimens having a width of 50 mm x length of 100 mm x thickness of 3 mm were injection molded under the same conditions and allowed to stand for 24 hours in an atmosphere of 23 ° C. and a relative humidity of 50%.

-Apparent surface properties:

Specimens of width 100mm x length 100mm x thickness 3mm are injection molded under the same conditions, so that the surface cannot be felt at all by the naked eye. Good, if traces of minerals appear very rarely with a 3D measuring device but are not visible on the surface Good, if a trace of minerals on the surface of the specimen is observed with a 3D measuring device, it was considered normal (◎: Very good, ○: Good, △: Normal)

Table 1 shows the test results.

ingredient Example 1 Example 2 Example 3 Comparative Example 1 Comparative Example 2

Furtherance
(%) Polycarbonate ^{1 )} 55 55 55 55 55 G-ABS ^{2 )} 8 8 8 8 8 SAN ^{3 )} 6 6 6 6 6 BDP (Takeover Flame Retardant) 10 10 10 10 10 Weapon filler Talc-1 ⁴⁾ 6 10 14 20 0 Talc-2 ⁵⁾ 14 10 6 0 20 Additive ^{6 )} 0.8 0.8 0.8 0.8 0.8
evaluation
Item Flexural modulus (kgf / cm2) 45,500 43,500 42,500 39,000 42,000 Impact Strength (kgf.cm/cm) 5 6 6 5 3 Heat deformation temperature (캜) 93 93 94 93 93 Mold Shrinkage (%) 0.21 0.21 0.23 0.25 0.27 Surface Properties ^{6 )} ◎ ◎ ◎ ◎ △ Flame Retardant Characteristics (1.0mm) V-0 V-0 V-0 V-0 V-0

1) Bisphenol A polycarbonate Mw (g-mol) = 20,000

2) ABS graft polymer comprising polybutadiene, styrene, acrylonitrile

3) Styrene-acrylonitrile copolymer containing acrylonitrile

4) Talc-1: Talc having an average particle size of 2.5㎛

5) Talc-2: Talc having a size of average particle diameter of 9.9㎛

6) Additives: heat stabilizer, wax, anti-driping agent

As can be seen from Table 1 above, Comparative Examples 1 and 2 were experiments by adding talc having a single particle size distribution (Comparative Example 1 was fine talc single, Comparative Example 2 was large talc single) to the polycarbonate resin composition. . On the other hand, Examples 1 to 3 were mixed in a polycarbonate resin composition by distilling fine talc and giant talc in a predetermined ratio within a predetermined range.

As a result, it was found that Examples 1 to 3 had no loss of impact strength and improved stiffness compared to Comparative Examples 1 and 2, in which talc having a single particle size distribution was added within a range where there was no loss of impact strength.

The case where an inorganic filler having a dual particle size distribution (Examples 1 to 3) is more excellent than when an inorganic filler having a single particle size distribution is used (Comparative Examples 1 and 2) for bending elastic modulus, impact strength, and surface properties. Showed characteristics. Although the effect of the addition of the inorganic filler having the binary particle size distribution varies depending on the talc ratio having the respective particle size distribution, it can be clearly seen that the synergistic effect is different compared to when only talc having a single particle size distribution is mixed.

That is, as can be seen from the above table, the polycarbonate resin composition according to the embodiments of the present invention has a much higher stiffness than the composition using a fine talc and a large talc than when using only talc having a single particle size distribution It has high impact and can be said to be good also in dimensional accuracy.

Claims (16)

40 to 90% by weight of an aromatic polycarbonate resin; 1 to 30% by weight of a styrenic copolymer; And 0.1 to 20 parts by weight of talc or mica, based on 100 parts by weight of the base resin consisting of 1 to 30% by weight of a rubber-styrene graft copolymer. The talc or mica 10 to 90% by weight of the talc or mica having an average particle diameter (d ₅₀ ) of 1㎛ or more and 4㎛ or less and 90 to 10% by weight of talc or mica having an average particle diameter (d ₅₀ ) of 7㎛ or more and 20㎛ or less. Polycarbonate resin composition consisting of. The method of claim 1, The talc or mica is 30 to 70% by weight of the talc or mica having an average particle diameter (d ₅₀ ) of 1㎛ or more and 4㎛ or less and 30 to 70% by weight of the talc or mica having an average particle diameter (d ₅₀ ) of 7㎛ or more and 20㎛ or less. Polycarbonate resin composition consisting of. The method of claim 1, The talc or mica is 30 to 70% by weight of talc or mica having an average particle diameter (d ₅₀ ) of 1 μm or more and 3 μm or less and 30 to 70 wt% of talc or mica having an average particle diameter (d ₅₀ ) of 9 μm or more and 15 μm or less. Polycarbonate resin composition consisting of. The method of claim 1, The aromatic polycarbonate resin in the base resin is 80 to 90% by weight, the rest of the polycarbonate resin composition is a styrene-based copolymer and rubber-styrene graft copolymer. The method of claim 1, The aromatic polycarbonate resin is a polycarbonate resin composition comprising 10 to 50% by weight of the branched polycarbonate resin in the total aromatic polycarbonate resin. The method of claim 1, The aromatic polycarbonate resin has a viscosity as measured in methylene chloride solution, average molecular weight (M _v) is 17,000 ~ 40,000 polycarbonate resin composition. The method of claim 1, The styrene-based copolymer resin, 50 to 95% by weight of styrene, α-methyl styrene, halogen or alkyl substituted styrene or a mixture thereof; And 50 to 5 weights of acrylonitrile, methacrylonitrile, C1-C8 methacrylic acid alkyl esters, C1-C8 acrylic acid alkyl esters, maleic anhydride, C1-C4 alkyl or phenyl N-substituted maleimides or mixtures thereof Polycarbonate resin composition which is a styrene-based copolymer copolymerized. The method of claim 1, The styrene-based copolymer resin is a carbonate-acrylonitrile copolymer polycarbonate resin composition. The method of claim 1, The rubber-styrene graft copolymer may comprise 50 to 95% by weight of styrene, α-methylstyrene, halogen or alkyl substituted styrene or mixtures thereof; And 50 to 5 weights of acrylonitrile, methacrylonitrile, C1-C8 methacrylic acid alkyl esters, C1-C8 acrylic acid alkyl esters, maleic anhydride, C1-C8 alkyl or phenyl N-substituted maleimides or mixtures thereof 5 to 95% by weight of the monomer mixture consisting of; Butadiene rubber, acrylic rubber, ethylene / propylene rubber, styrene / butadiene rubber, acrylonitrile / butadiene rubber, isoprene rubber, ethylene-propylene-diene terpolymer (EPDM) and polyorganosiloxane / polyalkyl (meth) acrylate A polycarbonate resin composition which is a rubber-styrene graft copolymer graft copolymerized to 5 to 95% by weight of at least one rubbery polymer selected from the group consisting of rubber composites. The method of claim 1, Wherein said rubber-styrene graft copolymer is an acrylonitrile butadiene styrene copolymer. The method of claim 1, The rubber-styrene graft copolymer has a polycarbonate resin composition having an average particle diameter (d ₅₀ ) of the rubbery polymer component of 0.05 to 4 μm. The method of claim 1, The resin composition polycarbonate resin composition further comprises 1 to 20 parts by weight of the phosphorus-based flame retardant based on 100 parts by weight of the base resin. 13. The method of claim 12, The phosphorus flame retardant is a polycarbonate resin composition which is a phosphate ester compound represented by the general formula of the following [Formula 2]. [Formula 2]

(In [Formula 2], R ₁ , R ₂ , R ₃ and R ₄ are each independently of each other, optionally halogenated C ₁ -C ₈ Alkyl, C ₆ -C ₂₀ aryl or C ₇ -C ₂₀ aralkyl, n is independently from each other 0 or 1, N is 0-10, and X is a mononuclear or polynuclear aromatic group having 6 to 30 carbon atoms. ) delete The method of claim 1, The resin composition is a polycarbonate resin composition further comprising a heat stabilizer, antioxidant, release agent, light stabilizer, ultraviolet absorber, pigment or dye. A molded article comprising the composition according to any one of claims 1 to 13.