KR20130077351A - Flame-retardant thermoplastic resin composition and molded article thereof - Google Patents

Abstract

PURPOSE: A flame retardant resin composition is provided to have excellent processability and mechanical strength while maintaining excellent flame retardancy and transparency. CONSTITUTION: A flame retardant resin composition comprises an aromatic polycarbonate resin; and a polysiloxane-polycarbonate copolymer which includes a hydroxy terminal siloxane represented by chemical formula 1 and a polycarbonate block represented by chemical formula 3 as a repeating unit. In the chemical formulas, R1 is hydrogen, halogen, a hydroxy group, a C1-20 alkyl group, an alkoxy group, or an aryl group; R2 is a C1-13 hydrocarbon group or a hydroxy group; R3 is a C2-8 alkylene group; A is X or NH-X-NH; m is an integer from 0-10; and n is an integer from 2-1,000.

Description

TECHNICAL FIELD [0001] The present invention relates to a flame-retardant thermoplastic resin composition,

The present invention relates to a flame-retardant thermoplastic resin composition and molded articles thereof, and more particularly to a flame-retardant thermoplastic resin composition and a molded article thereof, which are excellent in flame retardance, balance of physical properties such as transparency, And a molded article thereof. BACKGROUND OF THE INVENTION 1. Field of the Invention [0002] The present invention relates to a flame retardant thermoplastic resin composition.

Polycarbonate resins are widely used as electrical components, mechanical components and industrial resins because of their excellent heat resistance, mechanical properties (particularly impact strength) and transparency. In particular, when polycarbonate resin is used as a case material of TV housings, computer monitor housings, copiers, printers, notebook batteries, lithium batteries, etc., which generate a lot of heat in the electric and electronic fields, not only heat resistance and mechanical properties but also excellent flame resistance are required. .

The most common method used to impart flame retardancy to polycarbonate resins is to mix bromine or chlorine compounds, which are halogen flame retardants, with polycarbonate resins.

However, when halogen flame retardants are used, the flame retardant function is fully exhibited in the event of a fire, but hydrogen halide gas is generated during resin processing, which not only causes mold corrosion and environmental pollution problems, but also generates dioxin, a toxic gas harmful to the human body during combustion. Increasingly, regulations on use are expanding.

In order to cope with this, a flame retardant polycarbonate resin composition using a alkali metal salt as a non-halogen flame retardant and a fluorinated polyolefin resin at the same time as an anti-dripping agent has been developed.

However, in this case, due to the fluorinated ethylene-based resin and the metal salt-based flame retardant used to secure the flame retardancy of the polycarbonate resin, there is a problem in that transparency, which is one of the advantages of the polycarbonate resin, is lowered.

In order to overcome such a drop in transparency, an alloy with a silicone-based additive and a silicone-based copolymer has been proposed.

However, according to the research results of the present inventors, although the technology using a silicon additive has the advantage of being environmentally friendly as a non-halogen flame retardant, its transparency is still low and relatively expensive. In addition, there is a problem that application to large-sized products is limited because the liquidity is insufficient for injection into large-sized articles.

Accordingly, development of a polycarbonate resin composition capable of realizing harmonious physical properties such as excellent transparency, fluidity and low temperature impact strength while sufficiently exhibiting flame retardancy is required.

Korean Patent Publication No. 10-2007-0070326

Disclosure of Invention Technical Problem [8] Accordingly, the present invention has been made in view of the above problems, and it is an object of the present invention to provide a flame retardant thermoplastic resin composition having excellent flame retardancy, transparency, flowability and mechanical strength (particularly, low temperature impact strength).

The present invention relates to an aromatic polycarbonate resin; And a polysiloxane-polycarbonate copolymer comprising a hydroxyl-terminated siloxane of formula (1) and a polycarbonate block of formula (3) as recurring units:

[Formula 1]

(3)

According to another aspect of the present invention, there is provided a molded article of the flame retardant thermoplastic resin composition as described above.

The flame retardant thermoplastic resin composition according to the present invention maintains excellent flame retardancy and transparency through proper blending of a polysiloxane-polycarbonate copolymer of a specific structure and a thermoplastic aromatic polycarbonate resin, and also has processability (especially fluidity sufficient to inject a large injection molding product). ) It has excellent balance of physical properties such as mechanical strength (especially low temperature impact strength) and heat resistance, and thus can be usefully applied to various applications such as housings for office equipment and electrical and electronic products that require flame retardancy and transparency.

Hereinafter, the present invention will be described in more detail. The objects, features and advantages of the present invention will be easily understood by the following embodiments. The present invention is not limited to the embodiments described herein, but may be embodied in other forms. The embodiments introduced herein are provided so that the disclosure may be made thorough and complete, and the spirit of the present invention may be sufficiently delivered to those skilled in the art to which the present invention pertains. Therefore, the present invention is not limited by the following exemplary description and embodiments.

As used herein, the term "reaction product" means a material in which two or more reactants are formed by reaction.

In addition, although the terms "first", "second" and the like are used herein to describe a polymerization catalyst, the polymerization catalyst is not limited by these terms. These terms are merely used to distinguish polymerization catalysts from each other. For example, the first polymerization catalyst and the second polymerization catalyst may be the same kind of catalyst or different kinds of catalysts.

In addition, the English letter "R" used to represent hydrogen, a halogen atom and / or a hydrocarbon group, etc. in the chemical formula described herein has a subscript represented by a number, but the "R" is added to such a subscript. It is not limited by. "R" represents, independently of each other, hydrogen, a halogen atom and / or a hydrocarbon group. For example, regardless of whether two or more "R" have the same or different subscripts, these "R" s may represent the same hydrocarbon group or may represent different hydrocarbon groups.

[Flame retardant thermoplastic resin composition]

The flame retardant thermoplastic resin composition according to the present invention comprises an aromatic polycarbonate resin; And a polysiloxane-polycarbonate copolymer having a specific structure.

Aromatic polycarbonate (PC) resin

The aromatic polycarbonate resin contained in the flame retardant thermoplastic resin composition of the present invention is not particularly limited, and a thermoplastic aromatic polycarbonate resin commonly used in the art can be used.

In one embodiment, the aromatic polycarbonate resin can be prepared from dihydric phenols, carbonate precursors and molecular weight modifiers.

The dihydric phenol may be one of the monomers constituting the aromatic polycarbonate resin, and may be represented by the following formula (5).

[Chemical Formula 5]

In Formula 5,

X is an alkylene group, a linear, branched or cyclic alkylene group having no functional group, or a linear, branched or cyclic alkylene group containing a functional group such as sulfide, ether, sulfoxide, sulfone, ketone, naphthyl, Lt; / RTI > Preferably, X may be a straight, branched or cyclic alkylene group having 3 to 6 carbon atoms.

R ₁ and R ₂ independently represent a hydrogen atom, a halogen atom, or an alkyl group, for example, a linear, branched or cyclic alkyl group having from 1 to 20 carbon atoms and having from 3 to 20 carbon atoms (preferably, from 3 to 6 carbon atoms).

n and m independently represent the integer of 0-4.

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), etc. are mentioned, Preferably bisphenol A is used.

The carbonate precursor is another monomer constituting the aromatic polycarbonate resin, and non-limiting examples thereof include carbonyl chloride (phosphene), carbonyl bromide, bis halo formate, diphenyl carbonate, dimethyl carbonate, and the like. . Preferably, carbonyl chloride (phosgene) is used.

As the molecular weight modifier, a monofunctional compound similar to a monomer already known in the art, that is, a monomer used to prepare a thermoplastic aromatic polycarbonate resin may be used. Non-limiting examples of molecular weight modifiers include phenol-based derivatives (eg, para-isopropylphenol, para-tert-butylphenol (PTBP), para-cumylphenol, para-isooctylphenol, para) -Isononylphenol, etc.), and aliphatic alcohols, etc. are mentioned. Preferably, para-tert-butylphenol (PTBP) is used.

Examples of the aromatic polycarbonate resin prepared from such dihydric phenols, carbonate precursors and molecular weight modifiers include linear polycarbonate resins, branched polycarbonate resins, copolycarbonate resins, polyestercarbonate resins, and the like. These can be used individually or in mixture of 2 or more types.

The preferred viscosity average molecular weight (M _v , measured in methylene chloride solution) of the aromatic polycarbonate resin is 15,000 to 40,000, more preferably 17,000 to 30,000, most preferably 20,000 to 30,000. When the viscosity average molecular weight of the aromatic polycarbonate resin is less than 15,000, mechanical properties such as impact strength and tensile strength may be greatly reduced. If the viscosity average molecular weight is more than 40,000, problems may occur in processing of the resin due to an increase in melt viscosity.

The content of the aromatic polycarbonate resin is preferably 5 to 90% by weight, more preferably 10 to 70% by weight based on the total weight of the flame-retardant thermoplastic resin composition. If the content is less than 5% by weight based on the total weight of the composition, properties such as transparency, fluidity, heat resistance and impact strength at room temperature may be deteriorated. If the content exceeds 70% by weight, the relative content of the polysiloxane-polycarbonate copolymer Sufficient flame retardancy can not be exhibited and the low temperature impact strength may be lowered.

Polysiloxane-Polycarbonate Copolymer (Si-PC)

The polysiloxane-polycarbonate copolymer contained in the flame-retardant thermoplastic resin composition of the present invention comprises a hydroxyl-terminated siloxane of the following formula (1) and a polycarbonate block of the following formula (3) as repeating units.

[Formula 1]

In Formula 1,

R ₁ independently represents a hydrogen atom, a halogen atom, a hydroxy group, an alkyl group having 1 to 20 carbon atoms, an alkoxy group or an aryl group. For example, the halogen atom may be Cl or Br, the alkyl group may be an alkyl group having 1 to 13 carbon atoms such as methyl, ethyl or propyl, and the alkoxy group may be an alkoxy group having 1 to 13 carbon atoms such as methoxy, It may be ethoxy or propoxy, the aryl group may be an aryl group having 6 to 10 carbon atoms, such as phenyl, chlorophenyl or tolyl.

R ₂ independently represents a hydrocarbon group or a hydroxy group having 1 to 13 carbon atoms. For example, R ₂ is an alkyl group or alkoxy group having 1 to 13 carbon atoms, an alkenyl group or alkenyloxy group having 2 to 13 carbon atoms, a cycloalkyl group or cycloalkoxy group having 3 to 6 carbon atoms, an aryloxy group having 6 to 10 carbon atoms, An aralkyl group or an aralkoxy group having 7 to 13 carbon atoms, or an alkaryl group or an alkaryloxy group having 7 to 13 carbon atoms.

R ₃ independently represents an alkylene group having 2 to 8 carbon atoms.

A is X or NH-X-NH, wherein X is 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 halogen atom, an alkyl group, alkoxy Or a mononuclear or polynuclear arylene group having 6 to 30 carbon atoms substituted or unsubstituted with a group, an aryl group or a carboxyl group. For example, X is an aliphatic group substituted or unsubstituted with a halogen atom, an aliphatic group containing oxygen, nitrogen or sulfur atoms in the main chain, or an aryl which may be derived from bisphenol A, resorcinol, hydroquinone or diphenylphenol It may be a len group, for example, it may be represented by the formula 2a to 2h.

(2a)

[Formula 2b]

[Formula 2c]

(2d)

[Formula 2e]

(2f)

[Chemical Formula 2g]

[Chemical Formula 2h]

m independently represents an integer of 0-10, Preferably it represents the integer of 0-4.

n independently represents an integer of 2 to 1,000, preferably an integer of 2 to 500, more preferably an integer of 5 to 100.

In one embodiment, the hydroxy-terminated siloxane of Formula 1 may be a reaction product of the hydroxy-terminated siloxane of Formula 1a with an acyl compound (ie, hydroxy-terminated siloxane having an ester bond).

[Formula 1a]

In Formula 1a, R ₁ , R ₂ , R ₃ , m and n are the same as defined in Formula 1 above.

The hydroxy-terminated siloxane of Formula 1a may be, for example, by synthesizing a compound of Formula 1b having a double bond with a hydroxy group and a compound of Formula 1c containing silicon at a molar ratio of 2: 1 using a platinum catalyst. Can be prepared.

[Chemical Formula 1b]

In the above formula (1b), R ₁ and m are the same as defined in the above formula (1), and k represents an integer of 1 to 7.

[Chemical Formula 1c]

In Formula 1c, R ₂ and n are the same as defined in Formula 1 above.

)를 사용할 수 있으나, 반드시 이에 한정되는 것은 아니다. 또한 상기 화학식 1a의 히드록시 말단 실록산의 제조와 관련하여 미국특허 US 6,072,011호를 참조할 수 있다.Specifically, Dow Corning's siloxane monomer (

) Can be used, but is not necessarily limited thereto. See also US Pat. No. 6,072,011 regarding the preparation of the hydroxy terminated siloxanes of Formula 1a.

The acyl compound used for preparing the hydroxy terminal siloxane of Chemical Formula 1 may have, for example, an aromatic, aliphatic or mixed structure including both aromatic and aliphatic. When 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. In addition, the acyl compound may further include a halogen, oxygen, nitrogen or sulfur atom.

In another embodiment, the hydroxy-terminated siloxane of Formula 1 may be a reaction product of the hydroxy-terminated siloxane of Formula 1a with a diisocyanate compound (ie, a hydroxy-terminated siloxane having a urethane bond).

Here, the diisocyanate compound is, for example, 1,4-phenylenedi isocyanate (1,4-phenylenediisocyanate), 1,3-phenylenediisocyanate (1,3-phenylenediisocyanate) or 4,4'-methylenediphenyl di Isocyanate (4,4'-methylenediphenyl diisocyanate).

The polysiloxane-polycarbonate copolymer contained in the flame-retardant thermoplastic resin composition according to the present invention comprises a polycarbonate block of the following formula (3) as a repeating unit in addition to the hydroxyl-terminated siloxane of the above-mentioned formula (1).

(3)

In Formula 3,

R ₄ is an alkyl group having 1 to 20 carbon atoms (eg, an alkyl group having 1 to 13 carbon atoms), a cycloalkyl group (such as a cycloalkyl group having 3 to 6 carbon atoms), an alkenyl group (eg, an alkenyl group having 2 to 13 carbon atoms), An alkoxy group (eg, an alkoxy group having 1 to 13 carbon atoms), a halogen atom, or a nitro substituted or unsubstituted aromatic hydrocarbon group having 6 to 30 carbon atoms.

Here, the aromatic hydrocarbon group may be derived from a compound having a structure of Formula 3a.

[Chemical Formula 3]

In the above formula (3a)

X is an alkylene group, a linear, branched or cyclic alkylene group having no functional group, or a linear, branched or cyclic alkylene group containing a functional group such as sulfide, ether, sulfoxide, sulfone, ketone, naphthyl, Lt; / RTI > Preferably, X may be a straight, branched or cyclic alkylene group having 3 to 6 carbon atoms.

Each R ₆ independently represents a hydrogen atom, a halogen atom or an alkyl group, such as a linear, branched or cyclic alkyl group having 3 to 20 carbon atoms (preferably 3 to 6) carbon atoms.

n and m independently represent the integer of 0-4.

Examples of the compound of the formula 3a include bis (4-hydroxyphenyl) methane, bis (4-hydroxyphenyl) phenylmethane, bis (4-hydroxyphenyl) naphthylmethane and 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, 2,2-bis (4-hydroxyphenyl) propane, 2,2-bis (4-hydroxy Phenyl) 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-2,2-bis (4-hydroxyphenyl) pentane , 4,4-bis (4-hydroxyphenyl) heptane, diphenyl-bis (4-hydroxyphenyl) Tan, Resorcinol, Hydroquinone, 4,4'-dihydroxyphenyl ether [bis (4-hydroxyphenyl) ether], 4,4'-dihydroxy-2,5-di Hydroxydiphenyl 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-dichloro-4-hydroxyphenyl) cyclohexane, 1,1-bis (3,5-dimethyl-4-hydroxyphenyl) cyclo Dodecane, 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-hydrate Hydroxyphenyl) propane, 2,2-bis (3,5-dibromo-4-hydroxyphenyl) propane, 2,2-bis (3,5-dichloro-4-hydroxyphenyl) propane, 2,4 -Bis (4-hydroxyphenyl) -2-methyl-butane, 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'-dihydroxybenzofe , 4,4'-dihydroxy-diphenyl, methyl may be a hydroquinone, 1,5-dihydroxynaphthalene, and 2,6-dihydroxy naphthalene, but is not limited thereto. Representative of these is 2,2-bis (4-hydroxyphenyl) propane (bisphenol A). Other functional dihydric phenols can be found in US Pat. Nos. US 2,999,835, US 3,028,365, US 3,153,008 and US 3,334,154, and the dihydric phenols may be used singly or in combination of two or more. Can be used.

In a preferred embodiment, the polysiloxane-polycarbonate copolymer is one having the structure of formula 4a or 4b.

[Chemical Formula 4a]

(4b)

In Formulas 4a and 4b, R ₁ , R ₂ , R ₃ , m and n are as defined in Formula 1, R ₄ is as defined in Formula 3, and l represents an integer of 1 to 20.

The preferred content of the siloxane in the polysiloxane-polycarbonate copolymer contained in the flame retardant thermoplastic resin composition of the present invention is 0.5 to 20% by weight, more preferably 0.5 to 10% by weight. When the content of the siloxane is less than 0.5% by weight based on the total weight of the copolymer, flame retardancy and impact strength at low temperature may be lowered. When the content of the siloxane exceeds 20% by weight, transparency, fluidity, heat resistance, The physical properties such as strength may be lowered and the manufacturing cost may increase.

The polysiloxane-preferred viscosity average molecular weight of the polycarbonate copolymer (M _v) is 15,000 to 200,000, more preferably 15,000 to 70,000. If the viscosity average molecular weight of the copolymer is less than 15,000, the mechanical properties may be significantly deteriorated. If the viscosity average molecular weight is more than 200,000, the melt viscosity may increase, which may cause problems in processing the resin.

The content of the polysiloxane-polycarbonate copolymer is preferably 10 to 95% by weight, more preferably 30 to 90% by weight based on the total weight of the flame-retardant thermoplastic resin composition. When the content is less than 10% by weight based on the total weight of the composition, sufficient flame retardancy can not be exhibited and the low temperature impact strength may be lowered. When the content exceeds 95% by weight, the relative content of the aromatic polycarbonate resin is decreased, The physical properties such as impact strength may be lowered.

In order to improve the flame retardancy, the composition according to the present invention may further include a flame-retardant (or flame-retardant) known in the art in addition to the polysiloxane-polycarbonate copolymer. The flame retardant which can be used includes at least one selected from the group consisting of an organic phosphoric acid ester compound, a phosphazene compound, a metal salt compound and a halogen-containing compound, but is not limited thereto.

The metal salt compounds are generally known and can be used in large amounts in compounds containing polycarbonate. All metal salt compounds suitable for the polycarbonate-containing resin composition can be used in the composition according to the present invention. For example, salts of organic and inorganic sulfonates (e.g., sodium trichlorobenzenesulfonate), salts of sulfonesulfonates (e.g., potassium salts of diphenylsulfonesulfonate), salts of perfluorinated alkanesulfonic acids, and salts of sodium aluminum hexa Fluoride may be used, but is not necessarily limited thereto.

As the halogen-containing compound, other oligomeric or polymeric bromine compounds derived from decabromodiphenyl ether, octabromophenyl ether, octabromodiphenyl ether and tetrabromobisphenol A or nucleobibrominated polyphenylene ether may be used But is not limited thereto.

When such a separate flame retardant is included in the composition of the present invention, the amount thereof is 0.001 to 10 parts by weight, more preferably 0.1 to 7 parts by weight, per 100 parts by weight of the total amount of the aromatic polycarbonate resin and the polysiloxane-polycarbonate copolymer By weight. If the amount of the flame retardant is less than 0.001 part by weight based on 100 parts by weight of the total amount of the aromatic polycarbonate resin and the polysiloxane-polycarbonate copolymer, the flame retardancy synergistic effect may be insignificant. If the amount is more than 10 parts by weight, Physical properties such as strength and heat resistance may be deteriorated.

The composition according to the present invention may further comprise a metal compound (for example, antimony oxide) acting as a synergist. These synergists are generally used with halogen containing compounds. The composition according to the present invention may further contain an inorganic filler such as silica, silicate, alumina, glass fiber, glass bead, glass flake, clay, talc, mica, calcium carbonate or the like to increase rigidity, heat resistance and dimensional stability, These may be incorporated in an amount of 0.1 to 50% by weight based on the total weight of the composition. The composition according to the present invention may further contain an organic filler such as carbon fiber or carbon black to increase black color and conductivity, and they may be incorporated in an amount of 0.1 to 30% by weight based on the total weight of the composition. The composition according to the present invention may further contain an antioxidant, a heat stabilizer, a releasing agent, a lubricant, a UV stabilizer and the like in an amount of 0.01 to 0.5% by weight based on the total weight of the composition.

[Method of producing flame retardant thermoplastic resin composition]

The flame retardant thermoplastic resin composition according to the present invention comprises the steps of reacting a hydroxyl-terminated siloxane and an oligomeric polycarbonate under an interfacial reaction condition comprising an aqueous alkali solution and an organic phase to form a polysiloxane-polycarbonate intermediate; Polymerizing said intermediate using a first polymerization catalyst to prepare a polysiloxane-polycarbonate copolymer; And mixing the prepared polysiloxane-polycarbonate copolymer with an aromatic polycarbonate resin.

In a preferred embodiment, the step of forming the intermediate comprises mixing the hydroxy end siloxane and the oligomeric polycarbonate in a weight ratio of from 0.5: 99.5 to 20: 80 (more preferably from 0.5: 99.5 to 10: 90) .

The polycarbonate used to prepare the polysiloxane-polycarbonate copolymer may be an oligomeric polycarbonate having a viscosity average molecular weight of 800 to 20,000 (more preferably, 1,000 to 15,000). When the viscosity average molecular weight of the oligomeric polycarbonate is less than 800, the molecular weight distribution may be widened and physical properties may be reduced, and when the viscosity average molecular weight is more than 20,000, the reactivity may be decreased.

In one embodiment, the oligomeric polycarbonate may be prepared by adding the above-mentioned dihydric phenol compounds to an aqueous alkali solution to make a phenol salt state, and then reacting the phenols in a salt state to dichloromethane injected with phosgene gas. . For the preparation of oligomers it is desirable to maintain the molar ratio of phosgene to bisphenol in the range of about 1: 1 to 1.5: 1, more preferably about 1: 1 to 1.2: 1. If the molar ratio of phosgene to bisphenol is less than 1, the reactivity may be lowered. If the molar ratio of phosgene to bisphenol is more than 1.5, processability may decrease due to excessive molecular weight increase.

The oligomerization reaction may be generally carried out at a temperature in the range of about 15 to 60 DEG C, and an alkali metal hydroxide (e.g., sodium hydroxide) may be used to adjust the pH of the reaction mixture.

In one embodiment, forming the intermediate comprises forming a mixture comprising hydroxy terminated siloxane and an oligomeric polycarbonate, the mixture comprising a phase transfer catalyst, a molecular weight modifier, and a second polymerization catalyst. It may be. In addition, forming the intermediate may include forming a mixture comprising hydroxy-terminated siloxane and an oligomeric polycarbonate; And extracting the organic phase from the resulting mixture after completion of the reaction of the hydroxy terminal siloxane with the oligomeric polycarbonate, wherein polymerizing the intermediate comprises providing a first polymerization catalyst to the extracted organic phase. It may be to include.

Specifically, the polysiloxane-polycarbonate copolymer may be prepared by adding the hydroxy-terminated siloxane of Formula 1 to an organic phase-water mixture containing a polycarbonate, and gradually introducing a molecular weight regulator and a catalyst.

As the molecular weight regulator, a monofunctional compound similar to the monomer used for preparing the polycarbonate may be used as described above. Preferably, para-tert-butylphenol (PTBP) is used.

As the catalyst, a polymerization catalyst and / or a phase transfer catalyst may be used. As the polymerization catalyst, for example, triethylamine (TEA) can be used. As the phase transfer catalyst, for example, a compound of the following formula (6) can be used.

[Formula 6]

^{_{(R 7) 4 Q + X}} -

In the above formula (6), R ₇ represents an alkyl group having 1 to 10 carbon atoms, Q represents nitrogen or phosphorus, and X represents a halogen atom or -OR ₈ . Here, R <_8> represents a hydrogen atom, a C1-C18 alkyl group, or a C6-C18 aryl group.

Specifically, the phase transfer catalyst is, for example, [CH ₃ (CH ₂ ) ₃ ] ₄ NX, [CH ₃ (CH ₂ ) ₃ ] ₄ PX, [CH ₃ (CH ₂ ) ₅ ] ₄ NX, [CH ₃ (CH ₂ ) ₆ ] ₄ NX, [CH ₃ (CH ₂ ) ₄ ] ₄ NX, CH ₃ [CH ₃ (CH ₂ ) ₃ ] ₃ NX, CH ₃ [CH ₃ (CH ₂ ) ₂ ] ₃ NX have. In the above formulas, X represents Cl, Br or -OR ₈ , wherein R ₈ represents a hydrogen atom, an alkyl group having 1 to 18 carbon atoms or an aryl group having 6 to 18 carbon atoms.

The content of the phase transfer catalyst is preferably about 0.01 to 10% by weight, more preferably 0.1 to 10% by weight, based on the total weight of the mixture of hydroxy terminal siloxane and oligomeric polycarbonate. If the content is less than 0.01% by weight may be less reactive, if the content is more than 10% by weight may precipitate as a precipitate or the transparency may be reduced.

In one embodiment, the polysiloxane-polycarbonate copolymer is prepared, and then the organic phase dispersed in methylene chloride is alkali washed and then separated. Subsequently, the organic phase is washed with 0.1N hydrochloric acid solution, and then washed twice with distilled water. When the washing is completed, the concentration of the organic phase dispersed in methylene chloride is constantly adjusted to granulate with a certain amount of pure water in the range of 30 to 100 ° C, preferably in the range of 60 to 80 ° C. If the temperature of the pure water is less than 30 ℃ assembling rate may be very long, the assembly time may be very long, and if the temperature of the pure water exceeds 100 ℃ it may be difficult to obtain the shape of the polycarbonate with a certain size. When the assembly is complete, it is preferable to dry for 5 to 10 hours at 100 to 120 ℃, more preferably first to dry for 5 to 10 hours at 100 to 110 ℃, second to 110 to 120 ℃ for 5 to 10 hours .

The method of mixing the polysiloxane-polycarbonate copolymer thus prepared and the aromatic polycarbonate resin is not particularly limited. Preferably, the polysiloxane-polycarbonate copolymer and the aromatic polycarbonate resin are kneaded at a weight ratio of 10: 90 to 95: 5 to finally prepare the flame-retardant thermoplastic resin composition of the present invention.

[Molded article of flame retardant thermoplastic resin composition]

According to another aspect of the present invention, there is provided a molded article of the flame retardant thermoplastic resin composition of the present invention as described above. The method for molding the composition of the present invention into a molded article is not particularly limited, and the molded article may be manufactured using a method generally used in the plastic molding field.

The molded article produced from the flame retardant thermoplastic resin composition of the present invention can be usefully applied to interior materials and exterior materials that require flame retardancy and transparency, such as computer terminals, office equipment, and housings of electrical and electronic products.

Hereinafter, the present invention will be described in more detail with reference to examples and comparative examples. However, the scope of the present invention is not limited thereto.

Examples and Comparative Examples

The raw materials as shown in Table 1 below were mixed by a Henschel mixer and uniformly dispersed therein. The mixture was extruded at a temperature of 240 to 270 ° C in a biaxial melt kneading extruder having L / D = 40 and? = 25 mm to obtain pellets Dried at 80 to 120 ° C. in a hot air drier for 4 hours or more, and injection molded at a temperature of 260 to 280 ° C. to prepare test pieces.

The raw materials used were as follows.

(A) Aromatic Polycarbonate Resin

The linear polycarbonate derived from bisphenol A: TRIREX 3022IR, intrinsic viscosity 0.50 dl / g, (25 ℃ , measured in methylene chloride), viscosity-average molecular weight (M _v) 21,200

(B) Polysiloxane-polycarbonate copolymer

<Preparation of hydroxy terminal siloxane>

A condenser was mounted in a 500 mL three-necked flask, and 0.4 mole of monomer BY16-799 from Dow Corning was dissolved in 300 mL of chloroform under nitrogen atmosphere, and 67 mL of triethylamine (TEA) catalyst was added thereto. 0.2 mol of terephthaloylchloride (TCL) was dissolved in 1,000 mL of chloroform while refluxing the solution, and then slowly added for 1 hour and refluxed for 12 hours. After removing the solvent of the reaction solution, dissolved in acetone (acetone) and washed with hot distilled water. Hydroxy terminal siloxanes having ester bonds of the following formula (7) were prepared by drying in a vacuum oven for 24 hours. The peaks of the methylene group of the polysiloxane observed at 2.6 ppm by H-NMR and the hydrogen peak of the benzene ring of TCL observed at 8.35 ppm and the hydrogen peak of the benzene ring of polysiloxane observed at 6.75 to 7.35 ppm It was confirmed.

[Formula 7]

&Lt; Preparation of polysiloxane-polycarbonate copolymer >

Bisphenol A in aqueous solution and phosgene gas were interfacially reacted in the presence of methylene chloride to prepare 400 mL of an oligomeric polycarbonate mixture having a viscosity average molecular weight of about 1,000. In the obtained oligomeric polycarbonate mixture, hydroxy-terminated siloxane (4.5 wt%) having an ester bond of the formula (7), tetrabutyl ammonium chloride (TBACl) dissolved in methylene chloride, 1.8 mL, p-tert -1.5 g of butylphenol (PTBP) and 275 [mu] l of triethylamine (triethylamine, TEA, 15wt% aqueous solution) were mixed and reacted for 30 minutes. The reacted oligomeric polycarbonate mixture was allowed to stand still and layer separation occurred, followed by extracting only the organic phase. The mixture was reacted for 2 hours by mixing 170 g of sodium hydroxide aqueous solution, 360 g of methylene chloride, and 300 µl of 15 wt% aqueous solution of triethylamine. After phase separation, the organic phase having increased viscosity was separated after alkali washing. Subsequently, the organic phase was washed with 0.1N hydrochloric acid solution and then repeatedly washed 2-3 times with distilled water. The washing was completed and the concentration of the organic phase was granulated with a certain amount of pure water at a constant 76 ° C. After the assembly was completed, the mixture was first dried at 110 ° C. for 8 hours and secondly at 120 ° C. for 10 hours. The peak of the methylene group of polysiloxane observed at 2.6 ppm and 2.65 ppm by H-NMR and the hydrogen peak of the benzene ring of polysiloxane observed at 6.95 to 7.5 ppm and the hydrogen peak of the benzene ring of TCL observed at 8.35 ppm M _v : 21,000).

At this time, H-NMR data and viscosity average molecular weight (M _v ) was measured by the following method.

(a) H-NMR (nuclear magnetic resonance spectroscopy): Measured using a Bruker Avance DRX 300.

(b) Viscosity Average Molecular Weight (M _v ): The viscosity of the methylene chloride solution was measured at 20 ° C. using an Ubbelohde Viscometer, from which the ultimate viscosity [η] was calculated by the following equation.

[?] = 1.23 x 10 ^-5 M _v ^0.83

(C) flame retardant compound

(C.1) Aromatic sulfonic acid flame retardant

[Formula 8]

In Formula 8,

R ₁ and R ₂ are each independently selected from the group consisting of an aliphatic group having 1 to 6 carbon atoms, a phenyl group, a biphenyl group, an alkyl-substituted phenyl group and a combination thereof, M is a metal cation group, x is 0 to 6 And y is an integer of 1 to 6.

(C.2) Metal salt of perfluoroalkanesulfonic acid

[Chemical Formula 9]

In the above formula (9)

M is a metal cationic group, and j is an integer of 1 to 8;

[Table 1]

Property measurement

The physical properties of the molded molded product specimens according to Examples 1 to 7 and Comparative Examples 1 to 5 were measured by the following methods, and the results are shown in Table 3 below.

(1) fluidity was measured at 300 ℃, 1.2kg _f in accordance with ASTM D1238.

(2) Impact strength: A notch was applied to the test piece in accordance with ASTM D256. The final test results were calculated as the average of the test results of 10 specimens.

(3) Low Temperature Impact Strength: A notch was placed on the test piece in accordance with ASTM D256, and after staying at -50 캜 for 30 minutes, it was evaluated. The final test results were calculated as the average of the test results of 10 specimens.

(4) Total light transmittance: A specimen of 3 mm thickness was evaluated according to ASTM D1003.

(5) Color stability: Yellowness Index (YI) was measured by a transmission method according to ASTM D1925. At this time, in order to evaluate the coloring stability under the basic color and high-temperature processing conditions, the injection molding conditions were set to 270 DEG C and 300 DEG C, respectively, and injection molding was performed. The basic color was evaluated by the yellow index of the specimen molded at 270 DEG C and the color stability was evaluated from the change of the yellow index of the specimen molded at 270 DEG C and 300 DEG C (DELTA YI _{300 DEG C - 270 DEG C} ).

(6) Flammability: Measured by UL-94 flame retardancy test method prescribed by Underwriter's Laboratory Inc. (UL) of the United States. This method is to evaluate the flame retardancy from the burning time and drip property after applying the flame of the burner for 10 seconds to a fixed size specimen. The burning time is the length of time the specimen continues to burn during the flame after the flame has been removed, and the burning of the cotton by the drip is carried out by dripping water from the specimen for the label, about 300 mm below the bottom of the specimen And the flammability rating is divided according to Table 2 below. &Lt; tb &gt; &lt; TABLE &gt;

[Table 2]

[Table 3]

As shown in Table 3, in the case of Examples, the flame retardancy and the low temperature impact strength are superior to those of the Comparative Examples, and the physical properties such as transparency, fluidity, basic color, and color stability are also excellent.

Claims (8)

Aromatic polycarbonate resins; And
A flame retardant thermoplastic resin composition comprising a polysiloxane-polycarbonate copolymer comprising a hydroxy-terminated siloxane of Formula 1 and a polycarbonate block of Formula 3 as a repeating unit:
[Formula 1]

In Chemical Formula 1,
R ₁ independently represents a hydrogen atom, a halogen atom, a hydroxy group, an alkyl group having 1 to 20 carbon atoms, an alkoxy group or an aryl group,
R ₂ independently represents a hydrocarbon group or a hydroxyl group having 1 to 13 carbon atoms,
R ₃ independently represents an alkylene group having 2 to 8 carbon atoms,
A is X or NH-X-NH, wherein X is unsubstituted or substituted with a linear or branched aliphatic group, a cycloalkylene group having 1 to 20 carbon atoms, or a halogen atom, an alkyl group, an alkoxy group, an aryl group or a carboxyl group A mononuclear or polynuclear arylene group having 6 to 30 carbon atoms,
m independently represents an integer of 0 to 10,
n independently represents an integer of 2 to 1,000.
(3)

In Formula 3,
R ₄ represents an alkyl group, a cycloalkyl group, an alkenyl group, an alkoxy group, a halogen atom, or a substituted or unsubstituted aromatic hydrocarbon group having 6 to 30 carbon atoms. The method of claim 1,
Wherein the aromatic polycarbonate resin has a viscosity average molecular weight of 15,000 to 40,000. The method of claim 1,
Wherein the polysiloxane-polycarbonate copolymer has a structure represented by the following formula (4a) or (4b): &lt; EMI ID =
[Chemical Formula 4a]

(4b)

In Chemical Formulas 4a and 4b,
R ₁ independently represents a hydrogen atom, a halogen atom, a hydroxy group, an alkyl group having 1 to 20 carbon atoms, an alkoxy group or an aryl group,
R ₂ independently represents a hydrocarbon group or a hydroxyl group having 1 to 13 carbon atoms,
R ₃ independently represents an alkylene group having 2 to 8 carbon atoms,
R ₄ represents an alkyl group, a cycloalkyl group, an alkenyl group, an alkoxy group, a halogen atom, or a substituted or unsubstituted aromatic hydrocarbon group having 6 to 30 carbon atoms,
m independently represents an integer of 0 to 10,
n independently represents an integer from 2 to 1,000,
l represents the integer of 1-20. The method of claim 1,
Wherein the polysiloxane-polycarbonate copolymer has a viscosity average molecular weight of 15,000 to 200,000. The method of claim 1,
Wherein the content of siloxane in the polysiloxane-polycarbonate copolymer is 0.5 to 20% by weight. The method of claim 1,
5 to 90% by weight of the aromatic polycarbonate resin; And 10 to 95% by weight of the polysiloxane-polycarbonate copolymer. The method of claim 1,
A flame retardant selected from the group consisting of an organic phosphoric acid ester compound, a phosphazene compound, a metal salt compound and a halogen-containing compound is added in an amount of 0.001 to 10 parts by weight per 100 parts by weight of the total of the aromatic polycarbonate resin and the polysiloxane-polycarbonate copolymer By weight of the flame retardant thermoplastic resin composition. The molded article of the flame-retardant thermoplastic resin composition of any one of Claims 1-7.