A thermoplastic resin composition with excellent hardness, discoloration resistance, and impact resistance, and a molded article containing the same.

Abstract

The present invention relates to a thermoplastic resin composition and molded articles containing the same, which have excellent hardness, discoloration resistance, and impact resistance. More specifically, the present invention relates to a thermoplastic resin composition and molded articles containing the same, which contain polycarbonate resin, polysiloxane-polycarbonate copolymer, modified acrylic copolymer, alumina-based inorganic filler, triazine-based ultraviolet stabilizer, and core-shell type acrylic impact modifier in specific content ratios, and which have excellent scratch resistance, as well as excellent discoloration resistance and impact strength.

Description

Technical Field

[0001] The present invention relates to a thermoplastic resin composition excellent in hardness, discoloration resistance, and impact resistance, and a molded article containing the same. More specifically, the present invention relates to a thermoplastic resin composition containing a polycarbonate resin, a polysiloxane-polycarbonate copolymer, a modified acrylic copolymer, an alumina-based inorganic filler, a triazine-based ultraviolet stabilizer, and a core-shell type acrylic impact modifier in a specific content ratio, having excellent scratch resistance, and also having excellent discoloration resistance and impact strength, and a molded article containing the same.

Background Art

[0002] Polycarbonate resin is a general-purpose thermoplastic engineering plastic produced by polycondensation of bisphenol A and phosgene. Its glass transition temperature is 150°C, and it has excellent mechanical properties such as tensile strength and impact strength, dimensional stability, heat resistance, and optical transparency. Due to its excellent properties, its applications as a high-temperature resistant engineering plastic, such as the housing of electrical and electronic components and building and advertising panels, are expanding day by day.

[0003] In order to use polycarbonate resin as an exterior material, in addition to mechanical properties, scratch resistance (high hardness) is required. However, when performing post-treatment processes such as painting or vapor deposition to satisfy these properties, demerits occur in terms of economy and environment.

[0004] Therefore, a polycarbonate resin composition capable of producing a molded article with high hardness without applying surface coating (i.e., without coating) has been developed. For example, Patent Document 1 discloses a polycarbonate resin composition with improved scratch resistance, which contains polycarbonate, a polycarbonate-polysiloxane copolymer, and a modified acrylic copolymer. However, the composition disclosed in this patent has a very low impact resistance (i.e., the Izod notch impact strength based on ASTM D256 is at a level of 3 - 5 kgf·cm / cm) and low discoloration resistance (i.e., significant discoloration (yellowing) occurs when exposed to ultraviolet rays (UVB)), despite having a sufficient hardness level. Therefore, there is still a need for thermoplastic resin compositions using polycarbonate that have excellent scratch resistance, high hardness properties, and also excellent impact resistance and resistance to discoloration (yellowing). [Prior art documents] [Patent Documents]

[0005] [Patent Document 1] Korean Patent No. 10-1297160 [Overview of the project] [Problems that the invention aims to solve]

[0006] The object of the present invention is to provide a thermoplastic resin composition using polycarbonate and a molded article containing the same, which can provide molded articles with excellent hardness, impact resistance, and discoloration resistance (yellowing resistance) without the need for post-processing such as painting or vapor deposition, and which can be particularly suitable for use in unpainted products. [Means for solving the problem]

[0007] One aspect of the present invention provides a thermoplastic resin composition comprising: (A) a polycarbonate resin; (B) a polysiloxane-polycarbonate copolymer containing hydroxy-terminated siloxane and polycarbonate blocks as repeating units; (C) a modified acrylic copolymer; (D) an alumina-based inorganic filler; (E) a triazine-based ultraviolet stabilizer; and (F) a core-shell type acrylic impact modifier; wherein, per 100 parts by weight of the total amount of the composition, the content of component (A) is greater than 30 parts by weight but less than 70 parts by weight, the content of component (B) is greater than 15 parts by weight but less than 45 parts by weight, the content of component (C) is greater than 5 parts by weight but less than 25 parts by weight, the content of component (D) is greater than 0.1 parts by weight but less than 3 parts by weight, the content of component (E) is greater than 0.1 parts by weight but 3 parts by weight or less, and the content of component (F) is greater than 1 part by weight but less than 8 parts by weight.

[0008] In one embodiment, the viscosity-average molecular weight of the thermoplastic resin composition may be 15,000 to 40,000.

[0009] According to another aspect of the present invention, a molded article comprising the thermoplastic resin composition of the present invention is provided. [Effects of the Invention]

[0010] The thermoplastic resin composition according to the present invention has excellent scratch resistance of pencil hardness B or higher, excellent impact resistance of room temperature Izod (notched, 1 / 8 inch) impact strength of 30 kgfcm / cm or higher, and excellent discoloration resistance with a color difference (dE) of less than 3 after UVB (72h) irradiation, even without post-processing such as painting or vapor deposition. Therefore, it can be usefully applied to various products such as mobile phone casings, earphone casings, TV casings, refrigerator casings, copiers, and printers. [Modes for carrying out the invention]

[0011] The present invention will be described in more detail below.

[0012] The thermoplastic resin composition of the present invention comprises (A) a polycarbonate resin; (B) a polysiloxane-polycarbonate copolymer containing a hydroxy-terminated siloxane and a polycarbonate block as repeating units; (C) a modified acrylic copolymer; (D) an alumina-based inorganic filler; (E) a triazine-based ultraviolet stabilizer; and (F) a core-shell type acrylic impact modifier.

[0013] (A) Polycarbonate resin The polycarbonate resin included in the thermoplastic resin composition of the present invention can be a thermoplastic aromatic polycarbonate resin, which can be produced from a divalent phenol, a carbonate precursor, and a molecular weight modifier.

[0014] The aforementioned divalent phenols are monomers of polycarbonate resin having the following structure.

[0015] [ka]

[0016] In the formula, X includes all cases, including cases with and without functional groups such as alkyl groups, sulfides, ethers, sulfoxides, sulfones, and ketones. Preferably, X represents a linear, branched, or cyclic alkylene group, and more preferably, X represents a linear, branched, or cyclic alkylene group containing 1 to 10 carbon atoms. R1 and R2 each represent hydrogen, a halogen atom, and a linear, branched, or cyclic alkyl group, respectively. n and m may each be an integer from 0 to 4, independently of each other. Here, if n and / or m are 0, it means that R1 and / or R2 are hydrogen.

[0017] Non-restrictive examples of the aforementioned divalent phenols include bis(4-hydroxyphenyl)methane, bis(4-hydroxyphenyl)phenylmethane, bis(4-hydroxyphenyl)naphthylmethane, bis(4-hydroxyphenyl)-(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, and 2,2-bis(4-hydroxyphenyl)propane (bisphenol A), with bisphenol A being the most representative of these.

[0018] The carbonate precursor is another monomer of the polycarbonate resin, and it is preferable to use phosgene (carbonyl chloride). Non-restrictive examples of the carbonate precursor include carbonyl bromide, bishaloformate, diphenyl carbonate, or dimethyl carbonate.

[0019] As the molecular weight regulator, known and conventional compounds, that is, monofunctional substances similar to the monomers used in the production of thermoplastic aromatic polycarbonate resins can be used. As non-limiting examples, derivatives based on phenol (for example, p-isopropylphenol, p-tert-butylphenol, p-cumylphenol, p-isooctylphenol, p-isononylphenol, etc.) can be used, and various other materials such as aliphatic alcohols can also be used. Among these, it is most preferable to apply p-tert-butylphenol (PTBP).

[0020] Examples of the aromatic polycarbonate resin produced from such a dihydric phenol, carbonate precursor, and molecular weight regulator include linear polycarbonate resin, branched polycarbonate resin, copolycarbonate resin, and polyester carbonate resin, etc.

[0021] In an exemplary embodiment of the present invention, the viscosity-average molecular weight (M v ) preferably uses a thermoplastic aromatic polycarbonate resin of 15,000 to 40,000, more preferably 17,000 to 30,000. When the viscosity-average molecular weight is less than 15,000, mechanical properties such as impact strength and tensile strength may significantly decrease. Conversely, when it exceeds 40,000, the melt viscosity increases, and problems may occur in resin processing. In particular, from the aspect of mechanical properties such as impact strength and tensile strength, it is preferable that the viscosity-average molecular weight is 20,000 or more, and from the aspect of processability, it is preferable that the viscosity-average molecular weight is 30,000 or less.

[0022] The thermoplastic resin composition of the present invention contains the (A) polycarbonate resin in an amount of more than 30 parts by weight and less than 70 parts by weight based on 100 parts by weight of the total amount of the composition. When the content of the (A) component in 100 parts by weight of the total amount of the composition is 30 parts by weight or less, the scratch resistance of the composition may be poor. Conversely, when it is 70 parts by weight or more, the scratch resistance or impact resistance of the composition may be poor.

[0023] In one embodiment, with respect to 100 parts by weight of the total amount of the thermoplastic resin composition of the present invention, the component (A) may be, for example, more than 30 parts by weight, 31 parts by weight or more, 32 parts by weight or more, 33 parts by weight or more, 34 parts by weight or more, 35 parts by weight or more, 36 parts by weight or more, or 37 parts by weight or more, and may also be less than 70 parts by weight, 69 parts by weight or less, 68 parts by weight or less, 67 parts by weight or less, 66 parts by weight or less, 65 parts by weight or less, 64 parts by weight or less, 63 parts by weight or less, 62 parts by weight or less, 61 parts by weight or less, 60 parts by weight or less, 59 parts by weight or less, or 58 parts by weight or less, but is not particularly limited thereto.

[0024] (B) Polysiloxane-polycarbonate copolymer The polysiloxane-polycarbonate copolymer contained in the thermoplastic resin composition of the present invention contains hydroxy-terminated siloxane and polycarbonate blocks as repeating units.

[0025] In one embodiment, the weight average molecular weight (Mw) of the hydroxy-terminated siloxane contained in the polysiloxane-polycarbonate copolymer may be 2,500 to 15,000, more specifically 3,500 to 13,000, and even more specifically 4,000 to 9,000. If the weight average molecular weight of the hydroxy-terminated siloxane is less than 2,500, the effect of improving impact resistance may be reduced. Conversely, if it exceeds 15,000, the reactivity decreases, and problems may occur when synthesizing a polysiloxane-polycarbonate copolymer with a desired molecular weight.

[0026] In one embodiment, the content of the hydroxy-terminated siloxane in the polysiloxane-polycarbonate copolymer may be 6% by weight or more, 6.5% by weight or more, or 7% by weight or more with respect to 100% by weight of the copolymer. The upper limit of the hydroxy-terminated siloxane content in the copolymer is not particularly limited, but considering economy, it may be 15% by weight or less, 10% by weight or less, or 9% by weight or less.

[0027] In one embodiment, the hydroxy-terminated siloxane in the polysiloxane-polycarbonate copolymer has the following formula (1a) or the following formula (1):

[0028] [ka]

[0029] (In the formula, R1 independently represents a hydrogen atom, a halogen atom, a hydroxyl group, a C1-C20 alkyl group, an alkoxy group, or an aryl group. For example, the halogen atom may be Cl or Br, the alkyl group may be a C1-C13 alkyl group, such as methyl, ethyl, or propyl, the alkoxy group may be a C1-C13 alkoxy group, such as methoxy, ethoxy, or propoxy, and the aryl group may be a C6-C10 aryl group, such as phenyl, chlorophenyl, or tolyl.) R2 independently represents a hydrocarbon group or hydroxyl group having 1 to 13 carbon atoms. For example, R2 may be an alkyl or alkoxy group having 1 to 13 carbon atoms, an alkenyl or alkenyloxy group having 2 to 13 carbon atoms, a cycloalkyl or cycloalkoxy group having 3 to 6 carbon atoms, an aryloxy group having 6 to 10 carbon atoms, an aralkyl or aralkoxy group having 7 to 13 carbon atoms, or an alkaryl or alkaryloxy group having 7 to 13 carbon atoms. R3 independently represents an alkylene group with 2 to 8 carbon atoms. m is an independent integer between 0 and 4. n represents an integer between 30 and 200, preferably between 40 and 170, and more preferably between 50 and 120.

[0030] In one embodiment, the hydroxy-terminated siloxane of formula (1a) is a siloxane monomer manufactured by Dow Corning. [ka] You may use, but are not limited to, the following.

[0031] [ka]

[0032] [In the formula, R1, R2, R3 and m are synonymous with those defined in formula (1a), n is independently an integer between 15 and 100, preferably between 20 and 80, more preferably between 25 and 60, and A has the structure of formula (2) or (3) below:

[0033] [ka]

[0034] (In the formula, X is Y or NH-Y-NH, where Y represents a linear or branched aliphatic group having 1 to 20 carbon atoms, a cycloalkylene group (e.g., a cycloalkylene group having 3 to 6 carbon atoms), or a mononuclear or polynuclear arylene group having 6 to 30 carbon atoms that is substituted or unsubstituted with a halogen atom, an alkyl group, an alkoxy group, an aryl group, or a carboxyl group. For example, Y may be an aliphatic group substituted or unsubstituted with a halogen atom, an aliphatic group containing an oxygen, nitrogen, or sulfur atom in the main chain, or an arylene group that may be derived from bisphenol A, resorcinol, hydroquinone, or diphenylphenol, and may be represented, for example, by any of the following formulas (2a) to (2h):)

[0035] [ka]

[0036] [ka]

[0037] (In the formula, R4 represents an aromatic hydrocarbon group having 6 to 30 carbon atoms or an aromatic / aliphatic mixed hydrocarbon group, or an aliphatic hydrocarbon group having 1 to 20 carbon atoms, where R4 may have a structure containing a halogen, oxygen, nitrogen, or sulfur in addition to carbon and elementary atoms. For example, R4 may be phenyl, chlorophenyl, or tolyl (preferably phenyl).)

[0038] In one embodiment, the hydroxy-terminated siloxane of formula (1) may be a reaction product of the hydroxy-terminated siloxane of formula (1a) (where n is an integer from 15 to 100) and an acyl compound, the acyl compound may have, for example, an aromatic, aliphatic, or mixed structure containing both aromatic and aliphatic elements. If the acyl compound is aromatic or mixed, it may have 6 to 30 carbon atoms, and if it is aliphatic, it may have 1 to 20 carbon atoms. The acyl compound may further contain a halogen, oxygen, nitrogen, or sulfur atom.

[0039] In another embodiment, the hydroxy-terminated siloxane of formula (1) may be the reaction product of the hydroxy-terminated siloxane of formula (1a) (where n is an integer from 15 to 100) and a diisocyanate compound. Here, the diisocyanate compound may be, for example, 1,4-phenylenediisocyanate, 1,3-phenylenediisocyanate, or 4,4'-methylenediphenyldiisocyanate.

[0040] In yet another embodiment, the hydroxy-terminated siloxane of formula (1) may be a reaction product of the hydroxy-terminated siloxane of formula (1a) (where n is an integer from 15 to 100) and a phosphorus-containing compound (aromatic or aliphatic phosphate compound). Here, the phosphorus-containing compound can be represented by the following formula (1b).

[0041] [ka]

[0042] (In the formula, R4 is synonymous with the one defined in formula (3) above, and Z independently represents a phosphorus atom, a halogen atom, a hydroxyl group, a carboxyl group, an alkyl group (having 1 to 20 carbon atoms), an alkoxy group, or an aryl group.)

[0043] In one embodiment, the polycarbonate block in the polysiloxane-polycarbonate copolymer has the following formula (4).

[0044] [ka]

[0045] (In the formula, R5 represents a divalent alkyl group (having 1 to 20 carbon atoms) (e.g., a divalent alkyl group having 1 to 13 carbon atoms), a cycloalkyl group (e.g., a divalent cycloalkyl group having 3 to 6 carbon atoms), an alkenyl group (e.g., a divalent alkenyl group having 2 to 13 carbon atoms), an alkoxy group (e.g., a divalent alkoxy group having 1 to 13 carbon atoms), or a divalent aromatic hydrocarbon group having 6 to 30 carbon atoms, substituted or unsubstituted with a halogen atom or nitro.)

[0046] In the foregoing, the aromatic hydrocarbon group may be derived from a compound having the structure of the following formula (4a).

[0047] [ka]

[0048] (In the formula, X represents an alkylene group, a linear, branched, or cyclic alkylene group without functional groups, or a linear, branched, or cyclic alkylene group containing one or more functional groups such as sulfide, ether, sulfoxide, sulfone, ketone, naphthyl, or isobutylphenyl. Preferably, X may be a linear, branched, or cyclic alkylene group having 1 to 10 carbon atoms or 3 to 6 carbon atoms; R6 independently represents a hydrogen atom, a halogen atom, or an alkyl group, for example, a linear, branched, or cyclic alkyl group having 1 to 20 carbon atoms or 3 to 20 carbon atoms (preferably 3 to 6 carbon atoms); and n and m independently represent integers from 0 to 4.)

[0049] The compound of formula (4a) is, for example, bis(4-hydroxyphenyl)methane, bis(4-hydroxyphenyl)phenylmethane, bis(4-hydroxyphenyl)naphthylmethane, bis(4-hydroxyphenyl)-(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) 2,2-bis(4-hydroxyphenyl)propane, 2,10-bis(4-hydroxyphenyl)decane, 2-methyl-1,1-bis(4-hydroxyphenyl)propane, 2,2-bis(4-hydroxyphenyl)propane, 2,2-bis(4-hydroxyphenyl)butane, 2,2-bis(4-hydroxyphenyl)pentane, 2,2-bis(4-hydroxyphenyl)hexane, 2,2-bis(4-hydroxyphenyl)nonane, 2,2-bis(3-methyl-4-hydroxyphenyl)propane, 2,2-bis(3-fluoro-4-hydroxyphenyl)propane, 4-methyl Tyl-2,2-bis(4-hydroxyphenyl)pentane, 4,4-bis(4-hydroxyphenyl)heptane, diphenyl-bis(4-hydroxyphenyl)methane, resorcinol, hydroquinone, 4,4'-dihydroxyphenyl [bis(4-hydroxyphenyl) ether], 4,4'-dihydroxy-2,5-dihydroxydiphenyl ether, 4,4'-dihydroxy-3,3'-dichlorodiphenyl ether, bis(3,5-dimethyl-4-hydroxyphenyl) ether , bis(3,5-dichloro-4-hydroxyphenyl) ether, 1,4-dihydroxy-2,5-dichlorobenzene, 1,4-dihydroxy-3-methylbenzene, 4,4'-dihydroxydiphenol [p,p'-dihydroxyphenyl], 3,3'-dichloro-4,4'-dihydroxyphenyl, 1,1-bis(4-hydroxyphenyl)cyclohexane, 1,1-bis(3,5-dimethyl-4-hydroxyphenyl)cyclohexane, 1,1-bis(3,5-dimethyl-4-hydroxyphenyl)cyclododecane, 1,1-bis(4-hydroxyphenyl)cyclododecane, 1,1-bis(4-hydroxyphenyl)butane, 1,1-bis(4-hydroxyphenyl)decane, 1,4-bis(4-hydroxyphenyl)propane, 1,4-bis(4-hydroxyphenyl)butane, 1,4-bis(4-hydroxyphenyl)isobutane, 2,2-bis(4-hydroxyphenyl)butane, 2,2-bis(3-chloro-4-hydroxyphenyl)propane, bis(3,5-dimethyl-4-hydroxyphenyl)methane, bis(3,5-dichloro-4-hydroxyphenyl)methane, 2,2-bis(3,5-dimethyl-4-hydroxyphenyl)propane, 2,2-bis(3,5-dibromo-4-hydroxyphenyl)propane, 2,2-bis(3,5-dichloro-4-hydroxyphenyl)propane, 2,4- Examples include, but are not limited to, bis(4-hydroxyphenyl)-2-methylbutane, 4,4'-thiodiphenol [bis(4-hydroxyphenyl)sulfone], bis(3,5-dimethyl-4-hydroxyphenyl)sulfone, bis(3-chloro-4-hydroxyphenyl)sulfone, bis(4-hydroxyphenyl)sulfide, bis(4-hydroxyphenyl)sulfoxide, bis(3-methyl-4-hydroxyphenyl)sulfide, bis(3,5-dimethyl-4-hydroxyphenyl)sulfide, bis(3,5-dibromo-4-hydroxyphenyl)sulfoxide, 4,4'-dihydroxybenzophenone, 3,3',5,5'-tetramethyl-4,4'-dihydroxybenzophenone, 4,4'-dihydroxydiphenyl, methylhydroquinone, 1,5-dihydroxynaphthalene, and 2,6-dihydroxynaphthalene. A representative example among these is 2,2-bis(4-hydroxyphenyl)propane (bisphenol A). For other functional divalent phenols, refer to U.S. Patents US2,999,835, US3,028,365, US3,153,008, and US3,334,154, etc. These divalent phenols can be used individually or in combination of two or more.

[0050] As alternative monomers for the polycarbonate block, carbonate precursors such as carbonyl chloride (phosgene), carbonyl bromide, bishaloformate, diphenyl carbonate, or dimethyl carbonate can be used.

[0051] The polysiloxane-polycarbonate copolymer used in the present invention preferably has a viscosity-average molecular weight (Mv) of 15,000 to 30,000, and more preferably 17,000 to 22,000. If the viscosity-average molecular weight of the polysiloxane-polycarbonate copolymer is less than 15,000, the mechanical properties may be significantly reduced, and conversely, if it exceeds 30,000, problems may arise in resin processing due to an increase in melt viscosity.

[0052] The thermoplastic resin composition of the present invention contains the (B) polysiloxane-polycarbonate copolymer in an amount of more than 15 parts by weight and less than 45 parts by weight per 100 parts by weight of the total composition. If the content of component (B) in 100 parts by weight of the total composition is 15 parts by weight or less, the impact resistance of the composition may be poor, and conversely, if it is 45 parts by weight or more, the scratch resistance of the composition may be poor.

[0053] In one embodiment, with respect to 100 parts by weight of the total amount of the thermoplastic resin composition of the present invention, component (B) may be, for example, more than 15 parts by weight, 15.5 parts by weight or more, 16 parts by weight or more, 17 parts by weight or more, 18 parts by weight or more, 19 parts by weight or more, or 20 parts by weight or more, or less than 45 parts by weight, 44.5 parts by weight or less, 44 parts by weight or less, 43 parts by weight or less, 42 parts by weight or less, 41 parts by weight or less, or 40 parts by weight or less, but is not particularly limited to these.

[0054] (C) Modified acrylic copolymer The modified acrylic copolymer contained in the thermoplastic resin composition of the present invention is used to improve the scratch resistance of the resin composition.

[0055] In one embodiment, the modified acrylic copolymer may be a copolymer of an aromatic or alicyclic acrylic compound and a copolymerizable compound therewith, and the copolymerizable compound may be alkyl methacrylate, alkyl acrylate, unsaturated carboxylic acid, acid anhydride, acrylate containing a hydroxyl group, amides, nitriles, allyl glycidyl ether, glycidyl methacrylate, styrenes, or a combination thereof.

[0056] According to one embodiment of the present invention, the modified acrylic copolymer may be a copolymer of polymethyl methacrylate (PMMA), and more specifically, poly(methyl methacrylate-co-phenyl methacrylate) (PMPA).

[0057] In one embodiment, the weight-average molecular weight of the modified acrylic copolymer may be 10,000 to 20,000, more specifically 15,000 to 20,000.

[0058] The thermoplastic resin composition of the present invention contains the (C) modified acrylic copolymer in an amount of more than 5 parts by weight and less than 25 parts by weight per 100 parts by weight of the total composition. If the content of component (C) in 100 parts by weight of the total composition is 5 parts by weight or less, the scratch resistance of the composition may be poor, and conversely, if it is 25 parts by weight or more, the impact resistance of the composition may be poor.

[0059] In one embodiment, with respect to 100 parts by weight of the total amount of the thermoplastic resin composition of the present invention, the amount of component (C) may be, for example, more than 5 parts by weight, 5.5 parts by weight or more, 6 parts by weight or more, 7 parts by weight or more, 8 parts by weight or more, 9 parts by weight or more, or 10 parts by weight or more, or less than 25 parts by weight, 24.5 parts by weight or less, 24 parts by weight or less, 23 parts by weight or less, 22 parts by weight or less, 21 parts by weight or less, or 20 parts by weight or less, but is not particularly limited to these.

[0060] (D) Alumina-based inorganic filler The alumina (Al2O3)-based inorganic filler contained in the thermoplastic resin composition of the present invention is used to improve the scratch resistance of the resin composition.

[0061] In one embodiment, the average particle size of the alumina-based inorganic filler is 5.0 μm or less (for example, 10 to 50 μm), and more specifically, it may be 40 μm or less (for example, 20 to 40 μm), but is not limited thereto.

[0062] In one embodiment, the hardness of the alumina-based inorganic filler is 16 Gpa or higher (for example, 16 to 30 Gpa), and more specifically, it may be 20 Gpa or higher (for example, 20 to 25 Gpa), but is not limited thereto.

[0063] The thermoplastic resin composition of the present invention contains the alumina-based inorganic filler (D) in an amount of more than 0.1 parts by weight and less than 3 parts by weight per 100 parts by weight of the total composition. If the content of component (D) in 100 parts by weight of the total composition is 0.1 parts by weight or less, the scratch resistance of the composition may be poor, and conversely, if it is 3 parts by weight or more, the impact resistance of the composition may be poor.

[0064] In one embodiment, with respect to 100 parts by weight of the total amount of the thermoplastic resin composition of the present invention, component (D) may be, for example, more than 0.1 parts by weight, 0.15 parts by weight or more, 0.2 parts by weight or more, 0.3 parts by weight or more, 0.4 parts by weight or more, or 0.5 parts by weight or more, or less than 3 parts by weight, 2.9 parts by weight or less, 2.5 parts by weight or less, 2 parts by weight or less, or 1.5 parts by weight or less, but is not particularly limited to these.

[0065] (E) Triazine-based UV stabilizers The triazine-based ultraviolet stabilizer contained in the thermoplastic resin composition of the present invention is used to improve the discoloration resistance of the resin composition.

[0066] In one embodiment, the triazine-based ultraviolet stabilizer can absorb ultraviolet light having a wavelength in the range of 250 to 400 nm, and more specifically, it may be hydroxyphenyltriazine, but is not limited thereto.

[0067] The thermoplastic resin composition of the present invention contains the (E) triazine-based ultraviolet stabilizer in an amount of more than 0.1 parts by weight and up to 3 parts by weight per 100 parts by weight of the total composition. If the content of component (E) in 100 parts by weight of the total composition is 0.1 parts by weight or less, the discoloration resistance of the composition may be poor, and conversely, if it exceeds 3 parts by weight, the discoloration resistance of the composition will not improve further, which is undesirable from an economic standpoint.

[0068] In one embodiment, component (E) may be present in an amount of, for example, more than 0.1 parts by weight, 0.15 parts by weight or more, 0.2 parts by weight or more, 0.3 parts by weight or more, 0.4 parts by weight or more, 0.5 parts by weight or more, 0.6 parts by weight or more, 0.7 parts by weight or more, 0.8 parts by weight or more, 0.9 parts by weight or more, or 1 part by weight or more, with respect to 100 parts by weight of the total amount of the thermoplastic resin composition of the present invention. It may also be 3 parts by weight or less, 2.9 parts by weight or less, 2.8 parts by weight or less, 2.7 parts by weight or less, 2.6 parts by weight or less, 2.5 parts by weight or less, 2.4 parts by weight or less, 2.3 parts by weight or less, 2.2 parts by weight or less, 2.1 parts by weight or less, 2 parts by weight or less, 1.9 parts by weight or less, 1.8 parts by weight or less, 1.7 parts by weight or less, 1.6 parts by weight or less, 1.5 parts by weight or less, or 1.4 parts by weight or less, but is not particularly limited to these amounts.

[0069] (F) Core-shell type acrylic impact modifier The core-shell type acrylic impact modifier contained in the thermoplastic resin composition of the present invention is used to improve the impact resistance of the resin composition.

[0070] In one embodiment, the core-shell type acrylic impact modifier may be, but is not limited to, one or more copolymers with a core-shell structure selected from acrylate copolymers, ethylene-acrylate copolymers, polyalkyl methacrylate copolymers, or combinations thereof.

[0071] The thermoplastic resin composition of the present invention contains the (F) core-shell type acrylic impact modifier in an amount of more than 1 part by weight and less than 8 parts by weight per 100 parts by weight of the total composition. If the content of component (F) in 100 parts by weight of the total composition is 1 part by weight or less, the impact resistance of the composition may be poor, and conversely, if it is 8 parts by weight or more, the scratch resistance of the composition may be poor.

[0072] In one embodiment, component (F) may be included in an amount of, for example, more than 1 part by weight, 1.1 parts by weight or more, 1.5 parts by weight or more, 2 parts by weight or more, 2.5 parts by weight or more, or 3 parts by weight or more, with respect to 100 parts by weight of the total amount of the thermoplastic resin composition of the present invention, and may also be less than 8 parts by weight, 7.9 parts by weight or less, 7.5 parts by weight or less, 7 parts by weight or less, 6.5 parts by weight or less, or 6 parts by weight or less, but is not particularly limited thereto.

[0073] In addition to the above components, the thermoplastic resin composition of the present invention may further contain one or more other optional additives.

[0074] In one embodiment, the resin composition of the present invention may further contain inorganic fillers such as silica, silicate, glass fiber, glass bead, glass flake, clay, talc, mica, and calcium carbonate to enhance rigidity, heat resistance, and dimensional stability, and these may be included in an amount of 0.1 to 50% by weight relative to the total resin composition.

[0075] In one embodiment, the resin composition of the present invention may further contain a colorant, which may be present in an amount of 0.1 to 10% by weight relative to the entire resin composition.

[0076] In one embodiment, the resin composition of the present invention may further contain other stabilizers, such as heat stabilizers, in an amount of 0.1 to 5% by weight relative to the entire resin composition.

[0077] In one embodiment, the resin composition of the present invention may further contain other release agents, such as release agents and lubricants, in an amount of 0.01 to 0.5% by weight relative to the total resin composition.

[0078] According to another aspect of the present invention, a molded article comprising the thermoplastic resin composition of the present invention is provided.

[0079] The molded articles include interior and exterior materials that require scratch resistance, discoloration resistance, and impact resistance, and specifically include, but are not limited to, mobile phone casings and electrical and electronic product casings.

[0080] The present invention will be described in more detail below with reference to examples and comparative examples. However, the scope of the present invention is not limited to these.

[0081] Examples Ingredient description (A): Linear polycarbonate resin (PC) (TRIREX3022PJ, manufactured by SAMYANG CORPORATION) (B): Linear polysiloxane-polycarbonate copolymer having the following structure (TRIREXST6-3022PJ, manufactured by SAMYANG CORPORATION) [ka] (In the formula, o is an integer between 56 and 60, n is an independent integer between 28 and 30, and m is an integer between 1 and 38.) (C): Modified acrylic copolymer (PMPA, poly(methyl methacrylate-co-phenyl methacrylate) (SA256 (LXMMA), H880 (manufactured by Mitsubishi Chemical Co., Ltd.))) (D-1): Alumina-based inorganic filler (Renaflair White sapphire, manufactured by Merk) (D-2): Mica (RC1001, manufactured by CQV) (E-1): Triazine-based UV stabilizer (CYASORB UV5411, manufactured by SOLVAY) (E-2): Benzotriazole-based UV stabilizers (Tinuvin 1577 (BASF), T-1577 (Songwon)) (F-1): Core-shell type acrylic impact modifier (PARALOID EXL2313, manufactured by DOW Corporation) (F-2): Copolymer-type acrylic impact modifier (LA4285, manufactured by Kuraray) (F-3): MBS (methacrylate-butadiene-styrene) type impact modifier (M732, manufactured by KANEKA Corporation) (G): Heat stabilizers (SONG1076 (manufactured by Songwon), PETSAHS (manufactured by Clariant)) (H): Colorants (TiO2 and salt pigments) (Kronos 2233 (manufactured by Kronos), BL97 (manufactured by BASF))

[0082] The aforementioned coloring agent was added during the discoloration resistance test of the resin composition to provide a clear contrast in color changes.

[0083] Examples 1-12 and Comparative Examples 1-21 The components of the composition were mixed in a Henschel mixer according to the types and contents shown in Table 1 below, and uniformly dispersed. Next, the mixture was extruded into pellets at a temperature of 240-270°C using a twin-screw molten metal extruder with L / D=40 and Φ=25mm. The pellets were dried in a hot air dryer at 100-120°C for more than 4 hours, and then test specimens were prepared by injection molding at a temperature of 260-280°C. Subsequently, the following physical properties were measured and are shown in Table 1 below.

[0084] Methods for measuring physical properties (1) Izod impact strength (Izod): Measured in a greenhouse using 1 / 8-inch thick specimens in accordance with ASTM D256. Measured at room temperature in accordance with ASTM D256.

[0085] (2) Pencil hardness: In accordance with ASTM D3363, the pencil hardness was measured after leaving the test specimens at 23°C and 50% relative humidity for 48 hours. The surface of the test specimen was scratched three times, and the degree of the scratch marks was observed visually. If two or more pencil marks were produced on the surface of the test specimen, the pencil hardness grade was classified as follows: 6B-5B-4B-3B-2B-B-HB-FH-2H-3H-4H-5H-6H

[0086] (3) Discoloration resistance: After irradiating the test specimen with ultraviolet light (UVB) for 72 hours, the change in color (color difference: dE) before and after UV irradiation was measured using a colorimeter.

[0087] [Table 1-1] [Table 1-2] [Table 1-3]

[0088] As can be seen from the results in Table 1 above, the compositions of Examples 1 to 12 according to the present invention all have a pencil hardness of B or higher and excellent scratch resistance, a room temperature Izod (notched, 1 / 8 inch) impact strength of 30 kgfcm / cm or higher and excellent impact resistance, and a color difference (dE) of less than 3 after UVB (72h) irradiation and excellent discoloration resistance. On the other hand, the compositions of Comparative Examples 1, 8 to 10, 12, 13, 15, and 19 to 21 had poor scratch resistance, the compositions of Comparative Examples 2, 3, 7, 11, 14, 16, and 18 had poor impact resistance, and the compositions of Comparative Examples 4 to 6 and 17 had poor discoloration resistance.

Claims

1. A thermoplastic resin composition, (A) Polycarbonate resin; (B) Polysiloxane-polycarbonate copolymers comprising hydroxy-terminated siloxanes and polycarbonate blocks as repeating units; (C) Modified acrylic copolymer; (D) Alumina-based inorganic filler; (E) Triazine-based UV stabilizers; and (F) Core-shell type acrylic impact modifier; Includes, For every 100 parts by weight of the total composition, The content of component (A) is more than 30 parts by weight but less than 70 parts by weight, The content of component (B) is more than 15 parts by weight but less than 45 parts by weight, The content of component (C) is more than 5 parts by weight but less than 25 parts by weight, The content of component (D) is more than 0.1 parts by weight but less than 3 parts by weight, The content of component (E) is more than 0.1 parts by weight and 3 parts by weight or less. The content of component (F) is more than 1 part by weight but less than 8 parts by weight. Thermoplastic resin composition.

2. (A) The thermoplastic resin composition according to claim 1, wherein the polycarbonate resin is a thermoplastic aromatic polycarbonate resin.

3. (A) The thermoplastic resin composition according to claim 1, wherein the viscosity-average molecular weight of the polycarbonate resin is 15,000 to 40,000.

4. (B) The thermoplastic resin composition according to claim 1, wherein the hydroxy-terminated siloxane in the polysiloxane-polycarbonate copolymer has the following formula (1a) or the following formula (1). 【Chemistry 1】 (In the formula, R 1 R independently represents a hydrogen atom, a halogen atom, a hydroxyl group, an alkyl group, an alkoxy group, or an aryl group; 2 R independently represents a hydrocarbon group or a hydroxyl group; 3 (Independently, represents an alkylene group with 2 to 8 carbon atoms; m is an integer from 0 to 4; and n is an integer from 30 to 200.) 【Chemistry 2】 [In the formula, R 1 , R 2 , R 3 And m are synonymous with those defined in formula (1a) above; n is independently an integer between 15 and 100, and A represents the structure of formula (2) or (3) below. 【Transformation 3】 (In the formula, X is Y or NH-Y-NH, where Y represents a linear or branched aliphatic group having 1 to 20 carbon atoms, a cycloalkylene group, or a mononuclear or polynuclear arylene group having 6 to 30 carbon atoms, substituted or unsubstituted with a halogen atom, alkyl group, alkoxy group, aryl group, or carboxyl group.) 【Chemistry 4】 (In the formula, R 4 (This represents an aromatic hydrocarbon group or an aromatic / aliphatic mixed hydrocarbon group having 6 to 30 carbon atoms, or an aliphatic hydrocarbon group having 1 to 20 carbon atoms.)

5. (B) The thermoplastic resin composition according to claim 1, characterized in that the polycarbonate block in the polysiloxane-polycarbonate copolymer has the following formula (4). 【Transformation 5】 (In the formula, R 5 (This represents a divalent alkyl group, cycloalkyl group, alkenyl group, alkoxy group, or a divalent aromatic hydrocarbon group having 6 to 30 carbon atoms, substituted or unsubstituted with a halogen atom or nitro.)

6. (C) The thermoplastic resin composition according to claim 1, wherein the modified acrylic copolymer is poly(methyl methacrylate-co-phenyl methacrylate) (PMPA).

7. A molded article comprising the thermoplastic resin composition according to any one of claims 1 to 6.

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