KR100574085B1 - Flame Retardant Thermoplastic Resin Composition - Google Patents

Abstract

The present invention (A) 45 to 99 parts by weight of a thermoplastic polycarbonate resin; (B) styrene, α-methylstyrene, halogen or methyl substituted styrene, C ₁ -C ₈ methacrylic acid alkyl esters, C ₁ -C ₈ methacrylic acid esters, or mixtures thereof (B _1a ) 50 to 95 Parts by weight, and acrylonitrile, methacrylonitrile, C ₁ -C ₈ methacrylic acid alkyl esters, C ₁ -C ₈ methacrylic acid esters, maleic anhydride, C ₁ -C ₄ alkyl or phenyl N-substituted Maleimide, or a mixture thereof (B _1b ) 5 to 95 parts by weight of the monomer mixture (B ₁ ) consisting of 50 to 5 parts by weight of butadiene rubber, acrylic rubber, ethylene / propylene rubber, styrene / butadiene rubber, acrylonitrile / butadiene rubber , Rubbers having a glass transition temperature of -10 ° C. or lower, such as isoprene rubber, ethylene-propylene-diene terpolymer (EPDM), or polyorganosiloxane / polyalkyl (meth) acrylate rubber composites, or mixtures thereof (B ₂ 95 to 5 parts by weight of a polymer selected from 1 to 50 parts by weight of graft copolymer obtained by polymerization rapeuteu; (C) 50 to 95 weight of styrene, α-methylstyrene, ring-substituted styrene, C ₁ -C ₈ methacrylic acid alkyl esters, C ₁ -C ₈ methacrylic acid esters, or mixtures thereof (C ₁ ) Buwa acrylonitrile, methacrylonitrile, C ₁ -C ₈ methacrylic acid alkyl esters, C ₁ -C ₈ methacrylic acid esters, maleic anhydride, C ₁ -C ₄ alkyl or phenyl N-substituted maleimides Or 0 to 50 parts by weight of a vinyl copolymer or a mixture of copolymers obtained by copolymerizing 50 to 5 parts by weight of a mixture (C ₂ ) thereof; (D) 0.5 to 30 parts by weight of a mixture of the phosphate ester compound represented by the following general formula (I) with respect to 100 parts by weight of the mixture of (A), (B), and (C):

Wherein R ₁ , R ₂ , R ₄ and R ₅ are each C ₆ -C ₂₀ aryl or alkyl substituted C ₆ -C ₂₀ aryl groups, R ₃ is a C ₅ -C ₈ cycloalkylene group, M Is 0 or an integer of 1 to 5, and for mixtures the average M value is 0.1 to 5.0; And (E) 0.05 to 5 parts by weight of the fluorinated polyolefin resin with respect to 100 parts by weight of the mixture of (A), (B), and (C).

Description

Flame Retardant Thermoplastic Resin Composition

Field of invention

The present invention relates to thermoplastic resin compositions having excellent flame retardancy, heat resistance, and mechanical strength that can be used in housings of electrical and electronic products. More specifically, the present invention is excellent in flame retardancy, heat resistance, flowability and mechanical properties, and does not cause bleeding, and less black streaks even at high temperature and high-speed injection molding, so that the polycarbonate resin and rubber modified graft suitable for thin molding A thermoplastic resin composition comprising a copolymer, a vinyl copolymer, a phosphate ester compound, and a fluorinated polyolefin.

Background of the Invention

Polycarbonate resins are excellent in transparency, mechanical strength and heat resistance, and are widely used in applications such as electric, electronic products, and automobile parts. However, polycarbonate resins are used in blends with other types of resins in order to improve them since they have disadvantages of poor processability. For example, blends of polycarbonate / styrene-containing copolymers are resin mixtures that improve processability while maintaining high notch impact strength.

In addition, since this polycarbonate resin composition is generally applied to a large heat dissipating material such as a computer housing or other office equipment, it is essential to maintain flame retardancy and high mechanical strength. In order to impart flame retardancy to such resin compositions, conventionally, halogen-based flame retardants and antimony compounds have been used. U.S. Patent Nos. 4,983,658 and 4,883,835 disclose examples of the use of halogen containing compounds as flame retardants. However, when halogen-based flame retardants are used, the demand for resins that do not contain halogen-based flame retardants has been rapidly expanded recently due to the problem of human health of gases generated during combustion.

As a technique for imparting flame retardancy without using a halogen flame retardant, the most common at present is to use a phosphate ester flame retardant. U.S. Patent No. 4,692,488 discloses non-halogen aromatic polycarbonate resins, non-halogen SAN (styrene-acrylonitrile) copolymers, non-halogen phosphorus compounds, tetrafluoroethylene polymers and small amounts of ABS (acrylonitrile-butadiene-styrene) aerials. A thermoplastic resin composition composed of coalescing is disclosed. The use of phosphorus-based compounds and fluorinated alkane polymers to impart flame retardancy to PC / ABS blend resin compositions, as in U.S. Patent No. 4,692,488, can prevent the dropping of sparks during combustion. There is a problem that a surface crack occurs due to a bleeding out phenomenon that migrates to the surface of the molding.

U.S. Patent 5,030,675 discloses flame retardant resin compositions composed of aromatic polycarbonate resins, ABS copolymer resins, polyalkylene terephthalate resins, monomeric phosphoric acid esters, and fluorinated polyolefins. However, the above composition has some disadvantages in that the stress crack resistance is somewhat improved, but the impact resistance is lowered and the thermal stability is sharply lowered at the time of processing at a high temperature.

Phosphoric acid ester oligomers are also known to be used as flame retardants, and Japanese Patent Laid-Open No. 59-202,240 discloses a process for preparing such compounds and that the compounds can be used as flame retardants for polyamide or polycarbonate resins. However, the above patent does not show that the stress crack resistance is improved when the phosphate ester oligomer is used.

U. S. Patent No. 5,204, 394 discloses a flame retardant resin composition composed of an aromatic polycarbonate resin, a styrene-containing copolymer or a graft copolymer, and a phosphate ester oligomer derived from aromatic dihydric alcohols. In this case, since the fluidity of the resin composition is lowered and the hydrolysis resistance of the flame retardant is lowered, there is a problem that black streaks are generated during thin injection molding.

U.S. Patent 5,061,745 discloses flame retardant resin compositions composed of aromatic polycarbonate resins, ABS graft copolymers, vinyl copolymers, monomeric phosphate esters, and tetrafluoroethylene polymers. Due to the volatilization of the monomeric phosphate ester, the composition may cause a surface crack problem due to a bleeding phenomenon, and has a disadvantage in that the deterioration in heat resistance is severe.

U.S. Patent 5,672,645 discloses PC / ABS resin compositions consisting of aromatic polycarbonate resins, vinyl copolymers, graft copolymers, mixtures of monomeric and oligomeric phosphate esters, and fluorinated polyolefins. In this patent, resorcinol or hydroquinone derivatives are used as oligomeric phosphate esters, but these resorcinol or hydroquinone derived oligomeric phosphorus flame retardants have the advantages of less bleeding and improved heat resistance than monomeric phosphate esters. The resin composition has a disadvantage in that the fluidity of the resin composition is lowered and the hydrolysis resistance is lowered, thereby generating black streaks during high-temperature injection molding.

In order to solve the conventional problems, the present inventors have excellent flame retardancy, heat resistance, and mechanical properties, excellent fluidity, and excellent workability during thin molding, and do not cause a bleeding phenomenon in which the flame retardant moves to the surface of the injection molded product. In addition, it is composed of polycarbonate resin, rubber modified graft copolymer, vinyl copolymer, polyphosphate derived from cycloalkylene diols, and fluorinated polyolefin suitable for thin molding due to low black streaks even at high temperature and high speed injection molding. The resin composition was completed.

 An object of the present invention is to provide a flame retardant thermoplastic resin composition excellent in flame retardancy, heat resistance, and mechanical properties.

Another object of the present invention is to provide a flame-retardant thermoplastic resin composition suitable for thin molding because there is no stress cracking due to bleeding and less black lines are generated during injection molding.

The above and other objects of the present invention can be achieved by the present invention described below. Hereinafter, the content of the present invention will be described in detail.

The thermoplastic resin composition of the present invention comprises (A) 45 to 99 parts by weight of a thermoplastic polycarbonate resin; (B) styrene, α-methylstyrene, halogen or methyl substituted styrene, C ₁ -C ₈ methacrylic acid alkyl esters, C ₁ -C ₈ methacrylic acid esters, or mixtures thereof (B _1a ) 50 to 95 Parts by weight, and acrylonitrile, methacrylonitrile, C ₁ -C ₈ methacrylic acid alkyl esters, C ₁ -C ₈ methacrylic acid esters, maleic anhydride, C ₁ -C ₄ alkyl, phenyl N-substituted Maleimide, or a mixture thereof (B _1b ) 5 to 95 parts by weight of the monomer mixture (B ₁ ) consisting of 50 to 5 parts by weight of butadiene rubber, acrylic rubber, ethylene / propylene rubber, styrene / butadiene rubber, acrylonitrile / butadiene rubber Rubbers having a glass transition temperature of -10 ° C. or lower, such as isoprene rubber, ethylene-propylene-diene terpolymer (EPDM), polyorganosiloxane / polyalkyl (meth) acrylate rubber composite, or mixtures thereof (B ₂ ) Graft to 95 to 5 parts by weight of a polymer selected from 1 to 50 parts by weight of graft copolymer obtained were combined; (C) 50 to 95 weight of styrene, α-methylstyrene, ring-substituted styrene, C ₁ -C ₈ methacrylic acid alkyl esters, C ₁ -C ₈ methacrylic acid esters, or mixtures thereof (C ₁ ) Buwa acrylonitrile, methacrylonitrile, C ₁ -C ₈ methacrylic acid alkyl esters, C ₁ -C ₈ methacrylic acid esters, maleic anhydride, C ₁ -C ₄ alkyl or phenyl N-substituted maleimides Or 0 to 50 parts by weight of a vinyl copolymer or a mixture of copolymers obtained by copolymerizing 50 to 5 parts by weight of a mixture (C ₂ ) thereof; (D) 0.5 to 30 parts by weight of a mixture of the phosphate ester compound represented by the following general formula (I) with respect to 100 parts by weight of the mixture of (A), (B), and (C):

Wherein R ₁ , R ₂ , R ₄ and R ₅ are each C ₆ -C ₂₀ aryl or alkyl substituted C ₆ -C ₂₀ aryl groups, R ₃ is a C ₅ -C ₈ cycloalkylene group, M Is 0 or an integer of 1 to 5, and for mixtures the average M value is 0.1 to 5.0; And (E) 0.05 to 5 parts by weight of the fluorinated polyolefin resin with respect to 100 parts by weight of the mixture of (A), (B), and (C).

Hereinafter, phosphoric acid represented by (A) polycarbonate resin, (B) rubber modified graft copolymer, (C) vinyl type copolymer, and (D) general formula (I) which are each component of the thermoplastic resin composition of this invention. An ester compound and (E) fluorinated polyolefin resin are demonstrated in detail.

(A) polycarbonate resin

The aromatic polycarbonate resin (A) used in the preparation of the resin composition of the present invention can be prepared by reacting diphenols generally represented by the following general formula (II) with phosgene, halogen formate, or carbonic acid diester:

Wherein A represents C ₁ -C ₅ alkylene, C ₂ -C ₅ alkylidene, C _{5 to} C ₆ cycloalkylidene, -S- or -SO _2- .

Specific examples of the diphenol of the general formula (II) include hydroquinone, resorcinol, 4,4'-dihydroxydiphenyl, 2,2-bis- (4-hydroxyphenyl) -propane, 2,4-bis -(4-hydroxyphenyl) -2-methylbutane, 1,1-bis- (4-hydroxyphenyl) -cyclohexane, 2,2-bis- (3-chloro-4-hydroxyphenyl) -propane And 2,2-bis- (3,5-dichloro-4-hydroxyphenyl) -propane. Among them, 2,2-bis- (4-hydroxyphenyl) -propane, 2,2-bis- (3,5-dichloro-4-hydroxyphenyl) -propane, 1,1-bis- (4- Hydroxyphenyl) -cyclohexane and the like are preferable. More preferred and most industrially used aromatic polycarbonates are prepared from 2,2-bis- (4-hydroxyphenyl) -propane, also called bisphenol-A.

Suitable polycarbonates used in the production of the resin composition of the present invention include those having a weight average molecular weight of 10,000 to 200,000, preferably 15,000 to 80,000.

As the polycarbonate used in the preparation of the resin composition of the present invention, a branched chain may be used, preferably 0.05 to 2 mol% of a tri- or more polyfunctional compound based on the total amount of diphenols used for polymerization. For example, the compound may be prepared by adding a compound having a trivalent or higher phenol group.

In preparing the resin composition of the present invention, a polycarbonate homopolymer, a copolymer thereof, or a mixture thereof may be used as the polycarbonate.

In addition, the polycarbonate used in the production of the resin composition of the present invention may be partially or entirely replaced by an aromatic polyester-carbonate resin obtained by polymerization in the presence of an ester precursor, such as a bifunctional carboxylic acid.

(B) graft copolymer

The graft copolymer (B) used in the preparation of the resin composition of the present invention is (B _1a ) styrene, α-methylstyrene, halogen or methyl ring-substituted styrene, C ₁ -C ₈ methacrylic acid alkyl esters, C 50 to 95 parts by weight of _1- C ₈ methacrylic acid esters, or mixtures thereof, (B _1b ) acrylonitrile, methacrylonitrile, C ₁ -C ₈ methacrylic acid alkyl esters, C ₁ -C ₈ 5 to 95 parts by weight of a monomer mixture (B ₁ ) consisting of 50 to 5 parts by weight of methacrylic acid ester, maleic anhydride, C ₁ -C ₄ alkyl or phenyl N-substituted maleimide or mixtures thereof, and a glass transition temperature of -10 Butadiene rubber, acrylic rubber, ethylene / propylene rubber, styrene / butadiene rubber, acrylonitrile / butadiene rubber, isoprene rubber, ethylene-propylene-diene monomer terpolymer (EPDM) rubber, polyorganosiloxane / polyalkyl In (meth) acrylate rubber composite Luer binary group of one or more polymer (B ₂₎ is selected from the obtained 95-5 parts by weight of a graft polymerization.

The C ₁ -C ₈ methacrylic acid alkyl esters or C ₁ -C ₈ acrylic acid alkyl esters are monohydryl alcohols each containing 1 to 8 carbon atoms as esters of methacrylic acid or acrylic acid. As these specific examples, methacrylic acid methyl ester, methacrylic acid ethyl ester, or methacrylic acid propyl ester are mentioned, Among these, methacrylic acid methyl ester is especially preferable.

Preferred examples of the graft copolymer (B) include those obtained by graft copolymerization of styrene, acrylonitrile and (meth) acrylic acid alkyl ester monomers alone or in a mixture with butadiene rubber, acrylic rubber, or styrene / butadiene rubber. . More preferred graft copolymers (B) are ABS copolymers.

The particle diameter of the rubber (B ₂ ) is preferably used in the range of 0.05 to 4㎛ in order to improve the impact strength and the molding surface.

The method for preparing the graft copolymer is well known to those skilled in the art, and any one of emulsion polymerization, suspension polymerization, solution polymerization, or bulk polymerization may be used, and a preferred manufacturing method For example, the aromatic vinyl monomer is added in the presence of a rubbery polymer, followed by emulsion polymerization or bulk polymerization using a polymerization initiator.

(C) vinyl copolymer

Examples of the vinyl copolymer (C) used in the preparation of the resin composition of the present invention include (C ₁ ) styrene, α-methylstyrene, ring-substituted styrene, C ₁ -C ₈ methacrylic acid alkyl esters, and C ₁ -C 50 to 95 parts by weight of ₈ methacrylic acid esters, or mixtures thereof, (C ₂ ) acrylonitrile, methacrylonitrile, C ₁ -C ₈ methacrylic acid alkyl esters, C ₁ -C ₈ acrylic acid alkyl esters And vinyl-based copolymers obtained by copolymerizing 50 to 5 parts by weight of maleic anhydride, C ₁ -C ₄ alkyl or phenyl N-substituted maleimide, or a mixture thereof, or a mixture of these copolymers.

The C ₁ -C ₈ methacrylic acid alkyl esters or C ₁ -C ₈ acrylic acid alkyl esters are monohydryl alcohols having 1 to 8 carbon atoms as esters of methacrylic acid or acrylic acid, respectively. As these specific examples, methacrylic acid methyl ester, methacrylic acid ethyl ester, or methacrylic acid propyl ester are mentioned, Among these, methacrylic acid methyl ester is especially preferable.

The thermoplastic vinyl copolymer (C) used in the preparation of the resin composition of the present invention can be produced as a by-product in the preparation of the graft copolymer (B), in particular an excess of vinyl monomer in a small amount of rubbery polymer In the case of grafting, more occurs. The content of the copolymer (C) used in the preparation of the resin composition of the present invention does not include a by-product of the graft copolymer (B).

The copolymer (C) used in the production of the resin composition of the present invention is a thermoplastic resin and does not contain rubber.

As a preferable copolymer (C), the thing manufactured by emulsion polymerization, suspension polymerization, solution polymerization, or block polymerization using methacrylic acid methyl ester and (meth) acrylic acid methyl ester is mentioned.

Other preferred copolymers (C) include monomer mixtures of styrene and acrylonitrile and optionally methacrylic acid methyl ester, monomer mixtures of α-methylstyrene and acrylonitrile and optionally methacrylic acid methyl ester, or styrene or α- And those prepared from monomer mixtures of methyl styrene and acrylonitrile and optionally methacrylic acid methyl ester. The styrene / acrylonitrile copolymer as component (C) may be prepared by emulsion polymerization, suspension polymerization, solution polymerization, or bulk polymerization, and it is preferable to use those having a weight average molecular weight of 15,000 to 200,000.

Another preferred copolymer (C) used in the preparation of the resin composition of the present invention is a copolymer of styrene and maleic anhydride, which can be produced using a continuous bulk polymerization method and a solution polymerization method. The composition ratio of the two monomer components can be varied in a wide range, preferably, the content of maleic anhydride is 5 to 25% by weight. The molecular weight of the styrene / maleic anhydride copolymer as copolymer (C) may also be a wide range, but it is preferable to use those having a weight average molecular weight of 60,000 to 200,000 and intrinsic viscosity of 0.3 to 0.9.

The styrene monomers used in the preparation of the vinyl copolymer (C) used in the preparation of the resin composition of the present invention are other substituted styrenes such as p-methylstyrene, vinyltoluene, 2,4-dimethylstyrene and α-methylstyrene. It can be used instead of the monomer.

The vinyl copolymer (C) used in the production of the resin composition of the present invention described above is used alone or in a mixture of two or more thereof.

(D) phosphate ester compound

The phosphate ester compound used in the present invention is a phosphate ester compound alone or a mixture thereof having the structure of the following general formula (I).

In formula (I), R ₁ , R ₂ , R ₄ , R ₅ are each C ₆ -C ₂₀ aryl or alkyl substituted C ₆ -C ₂₀ aryl group, R ₃ is C ₅ -C ₈ cycloalkyl Is a len group, M represents a value of 0, 1, 2, 3, 4 or 5, and in the case of mixtures, their arithmetic mean is from 0.1 to 5.

Preferred R ₁ , R ₂ , R ₄ , and R ₅ are phenyl groups or phenyl groups substituted with alkyl groups such as t-butyl, isopropyl, isobutyl, isoamyl, t-amyl and the like.

Examples of cycloalkylenediols that can be used for R ₃ are cyclopentanediol, cyclo hexanediol, cyclo heptanediol, cyclo octanediol and the like. The method for preparing the phosphate ester flame retardant (D) used in the present invention is not particularly limited, but generally includes a dihydric alcohol of phosphorus oxychloride (POCl ₃ ) and cycloalkylenediols, and one hydroxy group such as phenol and cresol. It can be produced by reacting a phenyl group or an alkyl substituted phenyl group.

The content of the phosphate ester (D) used as the flame retardant of the thermoplastic resin composition of the present invention is preferably 0.5 to 30 parts by weight based on 100 parts by weight of the mixture of (A), (B), and (C).

(E) fluorinated polyolefin resin

Fluorinated polyolefin-based resins are conventionally available resins such as polytetrafluoroethylene, polyvinylidene fluoride, tetrafluoroethylene / vinylidene fluoride copolymer, tetrafluoroethylene / hexafluoropropylene copolymer and ethylene / Tetrafluoroethylene copolymer etc. are mentioned. These may be used independently from each other, and two or more different types may be used together.

When the fluorinated polyolefin resin is mixed and extruded together with the other component resins of the present invention, a fibrillar network is formed in the resin to lower the flow viscosity of the resin during combustion and increase the shrinkage rate to increase the shrinkage of the resin. Prevent the phenomenon.

The fluorinated polyolefin resin used in the preparation of the resin composition of the present invention may be prepared using a known polymerization method, for example, a pressure of 7 to 71 kg / cm ² and a temperature of 0 to 200 ℃, preferably 20 It can be prepared in an aqueous medium containing free radical forming catalysts such as sodium, potassium or ammonium peroxydisulfate at conditions of ˜100 ° C.

The fluorinated polyolefin resin may be used in an emulsion state or a powder state. When the fluorinated polyolefin resin in an emulsion state is used, the dispersibility in the entire resin composition is good, but the manufacturing process is complicated. Therefore, even in a powder state, it is preferable to use in a powder state as long as it can be properly dispersed in the entire resin composition to form a fibrous network structure.

Fluorinated polyolefin-based resins which can be preferably used for the preparation of the resin composition of the present invention include polytetrafluoroethylene having a particle size of 0.05 to 1,000 µm and specific gravity of 2.0 to 2.3 g / cm ² .

The content of the fluorinated polyolefin resin used in the preparation of the resin composition of the present invention is suitably 0.05 to 5 parts by weight based on 100 parts by weight of the mixture of the base resin components (A), (B), and (C).

In the thermoplastic resin composition of the present invention, in addition to the organophosphorus compound (D) described above for improving flame retardancy, flame retardants and flame retardants, which are generally widely used, such as other organophosphorous ester compounds, halogen-containing organic compounds, cyanate compounds, metal salts, and the like, Can be used additionally. Organic phosphate ester compounds that can be used include phosphate ester monomer compounds such as triphenylphosphate, tricresylphosphate and the like and condensed phosphate esters derived from dihydric alcohols such as resorcinol, hydroquinone and bisphenol-A.

The thermoplastic resin composition of the present invention may include general additives such as lubricants, mold release agents, nucleating agents, antistatic agents, stabilizers, reinforcing agents, inorganic additive pigments or dyes according to their respective applications, in addition to the above components. It can be used in the range of 0 to 60 parts by weight, preferably 10 to 40 parts by weight based on 100 parts by weight of the base resin components (A), (B), and (C).

The resin composition of the present invention can be produced by a known method for producing a resin composition. For example, the components of the present invention and other additives may be mixed simultaneously, then melt extruded in an extruder and prepared in pellet form.

The composition of the present invention can be used for molding various products, and is particularly suitable for producing thin molded articles such as notebook housings that require excellent flame retardancy and mechanical properties, excellent stress crack resistance, and excellent moldability.

Example

Hereinafter, the present invention will be described in detail by way of examples and comparative examples. However, the scope of the present invention is not limited by these examples.

(A) polycarbonate resin

A polycarbonate of type Bisphenol-A having a melt flow index (250 ° C., 10 kg load) measured according to ASTM D1238 of 20 g / 10 min was used.

(B) rubber modified graft copolymer

Butadiene rubber latex was added so that the butadiene content was 45 parts by weight based on the total amount of the monomers, 1.0 parts by weight of potassium oleate, cumene hydroperoxide, an additive necessary for a mixture of 36 parts by weight of styrene, 14 parts by weight of acrylonitrile, and 150 parts by weight of deionized water. 0.4 parts by weight, 0.3 parts by weight of mercaptan-based chain transfer agent was added to the reaction while maintaining at 75 ℃ for 5 hours to prepare an ABS graft latex. 1% sulfuric acid solution was added to the resulting polymer latex to coagulate, and then dried to prepare a graft copolymer resin in powder form.

(C) vinyl copolymer resin

A SAN copolymer resin was prepared by suspension polymerization by adding 0.2 parts by weight of azobisisobutyronitrile and 0.5 parts by weight of tricalcium phosphate, which are necessary additives to a mixture of 70 parts by weight of styrene, 30 parts by weight of acrylonitrile, and 120 parts by weight of deionized water. . The copolymer was washed with water, dehydrated and dried to obtain a SAN copolymer resin in powder form.

(D) phosphate ester compound

(D ₁ ) The phosphate ester compound derived from the cycloalkylenediols used in the examples of the present invention is cyclohexylene bis (diphenylphosphate) having an average M value of 1.2.

(D ₂ ) The phosphate ester compound used in Comparative Example 1 of the present invention is resorcinol bis (diphenylphosphate) having an average M value of 1.3.

(D ₃ ) The monophosphate used in Comparative Example 2 of the present invention is triphenylphosphate.

(E) fluorinated polyolefin resin

Teflon (trade name) 7AJ of Dupont, USA was used.

The composition of the components and the physical properties of the resin composition prepared thereby are shown in Table 1.

Each component, antioxidant, and heat stabilizer were added, mixed in a conventional mixer, extruded using a twin screw extruder having L / D = 35 and Φ = 45 mm, and then the extrudate was manufactured in pellet form. Specimens were prepared for the measurement of physical properties and the evaluation of the flame retardancy at ℃. These specimens were measured for 48 hours at 23 ° C. and 50% relative humidity, and then measured for physical properties according to ASTM standards.

Izod impact strength was evaluated using a 3.2 mm thick, V-notched specimen in accordance with ASTM D256. The heat deflection temperature was measured at 18.6 kgf load in accordance with ASTM D648.

The flame retardancy was evaluated using 1.2 mm thick specimens in accordance with UL94 regulations. The total combustion time was the sum of both primary and secondary combustion times when five specimens were evaluated.

Melt flow index was evaluated according to ASTM D1238, and the measurement conditions were evaluated at 220 ℃, 10 kg load.

The bleeding was evaluated by observing the surface of the injected product visually by injecting a container of 200 mm × 200 mm × 100 mm, thickness 3 mm using a 40-ounce injection machine.

The thermal stability and appearance of the resin composition were judged as the occurrence of black streak on the surface of the injection molding when a 200 mm × 50 mm × 2 mm size flat plate was injected. Injection temperature was varied in the range of 260 ~ 300 ℃, and evaluated while changing the injection pressure and speed.

Bleeding ^* X: No bleeding, O: Bleeding has occurred.

Appearance ^** X: No black streaks, O: Black streaks frequently.

As shown in Table 1, in the case of using a phosphate ester compound derived from cycloalkylene diols as a flame retardant as in the example, it has excellent flame retardancy and fluidity, and unlike the comparative example, the bleeding phenomenon occurs during injection molding. It can be seen that there is no black line.

The flame retardant thermoplastic resin composition according to the present invention is excellent in physical properties such as flame retardancy and impact strength, and is excellent in workability during injection molding, and is useful for manufacturing a thin molded product such as a notebook housing because there is no bleeding phenomenon and black lines.

Simple modifications or changes of the present invention can be easily carried out by those skilled in the art, and all such modifications or changes can be seen to be included in the scope of the present invention.                     

Claims (4)

(A) 45 to 99 parts by weight of the thermoplastic polycarbonate resin; (B) styrene, α-methylstyrene, halogen or methyl ring-substituted styrene, C ₁ -C ₈ methacrylic acid alkyl esters, C ₁ -C ₈ methacrylic acid esters or mixtures thereof (B _1a ) 50 to 95 parts by weight and acrylonitrile, methacrylonitrile, C ₁ -C ₈ methacrylic acid alkyl esters, C ₁ -C ₈ methacrylic acid esters, maleic anhydride, C ₁ -C ₄ alkyl or phenyl N- Substituted maleimide, or mixtures thereof (B _1b ) 5 to 95 parts by weight of the monomer mixture (B ₁ ) consisting of 50 to 5 parts by weight of butadiene rubber, acrylic rubber, ethylene / propylene rubber, styrene / butadiene rubber, acrylonitrile / butadiene Rubbers having a glass transition temperature of -10 ° C. or lower, such as rubbers, isoprene rubbers, terpolymers of ethylene-propylene-diene (EPDM), or polyorganosiloxane / polyalkyl (meth) acrylate rubber composites, or mixtures thereof (B 95-5 parts by weight of a polymer selected from ₂ ) 1 to 50 parts by weight of the graft copolymer obtained by graft polymerization on; (C) 50 to 95 parts by weight of styrene, α-methylstyrene, ring-substituted styrene, C ₁ -C ₈ methacrylic acid alkyl esters, C ₁ -C ₈ methacrylic acid esters or mixtures thereof (C ₁ ) Acrylonitrile, methacrylonitrile, C ₁ -C ₈ methacrylic acid alkyl esters, C ₁ -C ₈ methacrylic acid esters, maleic anhydride, C ₁ -C ₄ alkyl or phenyl N-substituted maleimides or 0 to 50 parts by weight of a vinyl copolymer or a mixture of copolymers obtained by copolymerizing 50 to 5 parts by weight of a mixture (C ₂ ) thereof; (D) 0.5 to 30 parts by weight of a mixture of the phosphate ester compound represented by the following general formula (I) with respect to 100 parts by weight of the mixture of (A), (B), and (C):

Wherein R ₁ , R ₂ , R ₄ and R ₅ are each C ₆ -C ₂₀ aryl or alkyl substituted C ₆ -C ₂₀ aryl groups, R ₃ is a C ₅ -C ₈ cycloalkylene group, M Is 0 or an integer of 1 to 5, and for mixtures the average M value is 0.1 to 5.0; And (E) A flame retardant thermoplastic resin composition comprising 0.05 to 5 parts by weight of a fluorinated polyolefin resin with respect to 100 parts by weight of a mixture of (A), (B), and (C). The R ₁ , R ₂ , R ₄ and R ₅ of the phosphate ester compound (D) are each a phenyl group or an alkyl group such as isopropyl, isobutyl, t-butyl, isoamyl and t-amyl. And a substituted phenyl group, R ₃ is a flame retardant thermoplastic resin composition derived from one or more mixtures selected from cyclopentanediol, cyclohexanediol, cycloheptanedol, and cyclooctanediol. The flame-retardant thermoplastic resin composition according to claim 1, wherein the average M value of the phosphate ester compound (D) is 0.1 to 3.0. The flame retardant thermoplastic resin composition according to claim 1, wherein the content of the phosphate ester compound (D) is 0.5 to 30 parts by weight based on 100 parts by weight of the mixture consisting of (A), (B), and (C).