KR20100050250A - Polylactic acid/polycarbonate resin composition - Google Patents

Abstract

PURPOSE: A polylactic acid/polycarbonate resin composition is provided to improve the outer appearance of an extruded article, and to apply the composition for manufacturing molded products including a vehicle and a battery electronic spare part. CONSTITUTION: A polylactic acid/polycarbonate resin composition contains 100 parts of base resin by weight formed with 10~90wt% of polycarbonate resin and 10~90wt% of polylactic acid, 1~50 parts of flame retardant by weight, and 1~20 parts of reactive core/shell structure reinforcing agent by weight. The polycarbonate resin has the average molecular weight of 10,000~35,000 grams per mol. The polylactic acid is formed with 95~100wt% of L-isomer and 0~5wt% of D-isomer.

Description

Polylactic acid / polycarbonate resin composition {POLYLACTIC ACID / POLYCARBONATE RESIN COMPOSITION}

The present invention relates to a polylactic acid / polycarbonate resin composition, and more particularly, to a polylactic acid / polycarbonate resin composition which significantly improves mechanical strength, heat resistance and flame retardancy, and improves appearance.

Until recently, research focused on the development of robust specialty polymer materials and the safety of polymer materials. However, as the problem of environmental pollution caused by waste polymers has become a social problem all over the world, the necessity of environmentally friendly polymer materials is required in recent years.

Such environmentally friendly polymers can be broadly classified into photodegradable and biodegradable polymers. The double biodegradable polymers have functional groups capable of being decomposed by microorganisms in the main chain structure.

Among these polymers, aliphatic polyester polymers are the most researched as biodegradable polymers because of their excellent processability and easy control of their decomposition properties. Especially, polylactic acid (PLA) forms the 150,000 ton market worldwide. In addition, the scope of application is expanding to the field where general plastics such as food packaging materials, containers, and electronics cases were used. To date, the main use of polylactic acid resins is in disposable products utilizing the biodegradable properties of polylactic acid, such as food containers, wraps, films and the like. The polylactic acid is currently being produced by Natureworks in the US and Toyota in Japan.

However, existing polylactic acid resins are easily broken in the case of thin film products due to lack of moldability, mechanical strength and heat resistance, and have low temperature resistance. there was.

Japanese Patent Laid-Open Nos. 2004-190026, 2006-335909, and 2006-182994 disclose a technique for mixing polylactic acid, polycarbonate, and flame retardant, but this is a simple melt mixing of the weak mechanical and thermal properties of polylactic acid. It merely supplements the properties with those of polycarbonate.

On the other hand, Japanese Patent Application Laid-Open No. 2006-111858 proposes a method of mixing a compatibilizer with a polylactic acid resin / polycarbonate resin to improve the appearance of a molded article. There is no role of improving heat resistance and, in particular, the effect of compatibilizer on flame retardancy is not considered.

One embodiment of the present invention is to provide a polylactic acid / polycarbonate resin composition to improve the mechanical strength, heat resistance, flame retardancy and appearance.

Another embodiment of the present invention is to provide a molded article prepared from the polylactic acid / polycarbonate resin composition.

However, technical problems to be achieved by the present invention are not limited to the above-mentioned problems, and other technical problems will be clearly understood by those skilled in the art from the following description.

One embodiment of the present invention (A) (a1) 100 parts by weight of the base resin consisting of 10 to 90% by weight of a polycarbonate resin and (a2) 10 to 90% by weight of a polylactic acid resin; (B) 1 to 50 parts by weight of a flame retardant; And (C) 1 to 20 parts by weight of an impact modifier of a reactive core / shell structure.

The impact modifier of the (C) reactive core / shell structure is a polymethyl (meth) acrylate having an epoxy group in a core formed of a rubber selected from the group consisting of acrylic rubber, butadiene rubber, silicone rubber, and copolymers thereof. The resulting shell has a grafted structure. 　

Another embodiment of the present invention provides a molded article prepared from the polylactic acid / polycarbonate resin composition.

Other specific details of embodiments of the present invention are included in the following detailed description.

According to the present invention, it has the effect of providing a polylactic acid / polycarbonate resin composition which remarkably improves mechanical strength, heat resistance and flame retardancy, and improves the appearance of an injection molded article, which is suitable for automobiles, mechanical parts, battery electronic parts, communication devices, It can be applied to molded products such as office equipment and sundries.

Hereinafter, embodiments of the present invention will be described in detail. However, it should be understood that the present invention is not limited thereto, and the present invention is only defined by the scope of the following claims.

The polylactic acid / polycarbonate resin composition of the present invention comprises: (A) 100 parts by weight of a basic resin consisting of 10 to 90% by weight of a polycarbonate-based resin and (a2) 10 to 90% by weight of a polylactic acid resin; (B) 1 to 50 parts by weight of a flame retardant; And (C) 1 to 20 parts by weight of the impact modifier of the reactive core / shell structure.

That is, the present invention supplements the limits of mechanical strength and heat resistance of polylactic acid by mixing polycarbonate with a polylactic acid resin, which is a biodegradable resin, and imparts flame retardancy by using a flame retardant, in particular an impact modifier including an epoxy group reactor. Use to maximize heat resistance, flame retardancy and appearance.

Hereinafter, each component of the polylactic acid / polycarbonate resin composition according to one embodiment of the present invention will be described in detail.

(A) Basic resin

The base resin of the present invention comprises (a1) polycarbonate (PC) -based resin and (a2) polylactic acid (PLA) resin.

(a1) polycarbonate resin

The polycarbonate resin used in the present invention may be prepared by reacting diphenols with a compound selected from the group consisting of phosgene, halogen formate, carbonic acid diester, and combinations thereof.

Specific examples of the diphenols include hydroquinone, resorcinol, 4,4'-dihydroxydiphenyl, 2,2-bis- (4-hydroxyphenyl) -propane (also called 'bisphenol-A'), 2, 4-bis- (4-hydroxyphenyl) -2-methylbutane, 1,1-bis- (4-hydroxyphenyl) -cyclohexane, 2,2-bis- (3-chloro-4-hydroxyphenyl ) -Propane, 2,2-bis- (3,5-dichloro-4-hydroxyphenyl) -propane, and the like, among which 2,2-bis- (4-hydroxyphenyl) -propane, 1 , 1-bis- (4-hydroxyphenyl) -cyclohexane, or 2,2-bis- (3,5-dichloro-4-hydroxyphenyl) -propane may be preferably used, more preferably 2 , 2-bis- (4-hydroxyphenyl) -propane may be used.

Such polycarbonate-based resins are easy to purchase commercially.

In addition, it is preferable to use the polycarbonate resin having a weight average molecular weight of 10,000 to 35,000 g / mol. It is possible to obtain physical properties such as excellent impact strength in the above molecular weight range, to have a suitable fluidity can be obtained excellent workability.

The polycarbonate resin according to the present invention is contained in 10 to 90% by weight, preferably 20 to 60% by weight relative to the base resin of the present invention. When the content of the polycarbonate-based resin is 10 to 90% by weight, it is excellent in heat resistance and impact strength, it can be expected environmentally friendly effect.

(a2) polylactic acid resin

In general, polylactic acid is a polyester resin produced by ester reaction using lactic acid obtained by decomposing corn starch as a monomer, and is easily commercially available.

The polylactic acid to be used in the present invention may include L-isomer, D-isomer, or L, D-isomer polylactic acid, and these polylactic acid resins may be used alone or in combination.

The polylactic acid preferably contains at least 95 wt% of L-isomers in terms of balance of heat resistance and moldability, and uses polylactic acid resins composed of L-isomers of 95 to 100 wt% and D-isomers of 0 to 5 wt%. It is preferable to use a polylactic acid resin which preferably consists of 98 to 99.99% by weight of the L-isomer and 0.01 to 2% by weight of the D-isomer. When the polylactic acid resin is composed of L-isomers # 95 to 100% by weight and D-isomers 0 to 5% by weight, it is possible to obtain not only a balance of heat resistance and moldability but also excellent hydrolysis resistance.

In addition, the polylactic acid resin has no specific limitation on molecular weight or molecular weight distribution if molding is possible, but it is preferable to use a weight average molecular weight of 80,000 g / mol or more, more preferably 80,000 to 300,000 g / mol. Good to do. When the weight average molecular weight of the polylactic acid resin is 80,000 kPa to 300,000 g / molk, it is excellent in terms of the balance between mechanical strength and heat resistance of the molded body.

The polylactic acid resin according to the present invention is preferably selected from the group consisting of polylactic acid polymers, polylactic acid copolymers, and combinations thereof.

The polylactic acid polymer is preferably a polymer prepared by ring-opening polymerization of a lactic acid selected from the group consisting of the L-isomer, the D-isomer, and a combination thereof.

The polylactic acid copolymer is a random or block copolymer with a component copolymerizable with the polylactic acid polymer. As another component copolymerizable with the said polylactic acid polymer, the compound which has a 2 or more ester bondable functional group in a molecule | numerator can be used preferably.

Examples of the compound having two or more ester bondable functional groups in the molecule include (a) dicarboxylic acids, (b) polyhydric alcohols, (c) hydroxy carboxylic acids other than lactic acid, (d) lactones, and (e) Various polyester, polyether, polycarbonate, etc. which are manufactured from the said compound are mentioned.

As said (a) dicarboxylic acid, C4-C50 linear or branched saturated or unsaturated aliphatic dicarboxylic acid, C8-C20 aromatic dicarboxylic acid, polyether dicarboxylic acid, etc. are mentioned. Can be.

At this time, the aliphatic dicarboxylic acid is preferably succinic acid, adipic acid, sebacic acid, decane dicarboxylic acid, and the like, and the aromatic dicarboxylic acid is preferably phthalic acid, terephthalic acid, isophthalic acid, and the like. As carboxylic acid, dicarboxylic acid which has a carboxymethyl group in the both terminal of polyalkylene ether, such as polyethylene glycol, polypropylene glycol, polybutylene glycol, polyethylene polypropylene glycol, is preferable.

Aliphatic polyols, aromatic polyhydric alcohols, polyalkylene ethers, etc. are mentioned as said (iii) polyhydric alcohol.

In this case, the aliphatic polyols include carbon atoms having 2 to 4 hydroxyl groups such as butane diol, hexane diol, octane diol, decane diol, 1,4-cyclohexanedimethanol, glycerin, sorbitan, trimethylolpropane, and neopentyl glycol. Aliphatic polyols of 2 to 50 are preferably used.

Moreover, as said aromatic polyhydric alcohols, C2-C4 alkylene oxides, especially ethylene, are contained in aromatic diols of 6 to 20 carbon atoms such as bis-hydroxy methyl benzene and hydroquinone, or bisphenols such as bisphenol A and bisphenol F. Aromatic diols obtained by addition reaction of an oxide, propylene oxide and butylene oxide are preferably used.

Moreover, as said polyalkylene ether, ether glycol, such as ethylene glycol, propylene glycol, diethylene glycol, triethylene glycol, polyethylene glycol, polypropylene glycol, can be used preferably.

As hydroxy carboxylic acid other than the said (c) lactic acid, C3-C10 hydroxy carboxylic acids, such as glycolic acid, hydroxy butyl carboxylic acid, and 6-hydroxy caproic acid, can be used preferably.

(D) Glycolide, (epsilon) -caprolactone glycolide, (epsilon) -caprolactone, (beta) -propiolactone, (delta) -butyrolactone, (beta) -butyrolactone, (gamma) -butyrolactone, (delta) Valerolactone or the like can be preferably used.

(E) The various polyesters, polyethers, polycarbonates can be used without limitation as long as they are conventionally used in the production of lactic acid copolymer, it is more preferable to use the polyester.

As said polyester, the aliphatic polyester manufactured from aliphatic dicarboxylic acid and aliphatic diol can be used preferably.

In this case, succinic acid, adipic acid, sebacic acid, decane dicarboxylic acid, etc. may be preferably used as the aliphatic dicarboxylic acid, and the aliphatic diol may be ethylene glycol, propane diol, butane diol, hexane diol, octane diol, and the like. Polyalkylene ethers (alone polymers or copolymers) such as aliphatic diols having 2 to 20 carbon atoms, polyethylene glycols, polypropylene glycols, and polybutylene glycols, polyalkylene carbonates, and the like.

The polylactic acid resin according to the present invention is contained in 10 to 90% by weight, preferably 20 to 80% by weight relative to the basic resin of the present invention. When the content of the polylactic acid resin is 10 to 90% by weight, it is excellent in heat resistance and impact strength, it can be expected environmentally friendly effect.

In the present invention, by using a polycarbonate resin mixed with a polylactic acid resin as a base resin, the mechanical strength and heat resistance of the polylactic acid may be compensated for.

(B) flame retardant

The flame retardant used in the present invention is not particularly limited, and specifically, at least one or more selected from the group consisting of phosphorus flame retardants, nitrogen compound flame retardants, silicone flame retardants, and inorganic flame retardants may be used.

The said phosphorus flame retardant is representatively organophosphorus compounds, such as phosphate ester and polyphosphate, and red phosphorus.

Specific examples of the phosphorus-based flame retardant include trimethyl phosphate, triethyl phosphate, tributyl phosphate, trihexyl phosphate, tributoxyethyl phosphate, triphenyl phosphate, tricrezyl phosphate, trixylenol phosphate, triisopropylphenyl phosphate, Triphenyl Phosphate, Trinaphthyl Phosphate, Cresyldiphenyl Phosphate, Cresinoldiphenyl Phosphate, Diphenyl Phosphate, Methacroyloxyethyl Acid Phosphate, Diphenylacryloyloxyethyl Phosphate, Diphenylmethacryloyloxyethyl Phosphate And condensed phosphate esters such as melamine phosphate, chimeramin phosphate, melamine pyrophosphate, triphenylphosphine oxide, tricresylphosphine oxide, methane phosphite diphenyl, phenyl phosphite hydroxyl phosphate and such condensates.

Commercially available condensed phosphate esters include PX-200, PX-201, PX-202, CR-733S, CR-741, CR-747, etc. of Daiji Chemical.

Examples of the nitrogen compound-based flame retardant include aliphatic amine compounds, aromatic amine compounds, nitrogen-containing heterocyclic compounds, cyan compounds, aliphatic amides, aromatic amides, urea, and thio urea.

Examples of the aliphatic amines include ethyl amine, butyl amine, diethyl amine, ethylene diamine, triethylene tetramine, diamino cyclohexane, diamino cyclooctane, gumanine, diamino purine, tripyridine, and triazine compounds. .

Examples of the silicone-based flame retardant include SiO _2, silicone resins, and silicone oils. The silicone resin may be a resin having a three-dimensional network structure capable of combining units of RSiO _3/2 , RSiO, and RSiO _1/2 . R represents an alkyl group, such as a methyl group, an ethyl group, a propyl group, an aromatic group, or the substituent which contained the vinyl group in the said substituent.

The silicone oil is polydimethyl siloxane and at least one methyl group of the side chain or terminal of the polydimethyl siloxane is hydrogen, alkyl group, cyclohexyl group, phenyl group, benzyl group, epoxy group, polyether group, carboxyl group, mercapto group, chloroalkyl group, alkyl Modified polysiloxanes modified by at least one selected from the group consisting of alcohol ester groups, alcohol groups, allyl groups, vinyl groups and trifluoro methyl groups or mixtures thereof.

As the inorganic flame retardant, magnesium hydroxide, aluminum hydroxide, antimony trioxide, antimony pentoxide, antimony, sodium carbonate, hydroxy zinc stannate, zinc stannate, meta stannate oxide, tin oxide, zinc lactate, zinc oxide, ferrous oxide, oxidizing agent Ferric iron, tin oxide, tin oxide, zinc borate, calcium borate, ammonium borate, ammonium octamolybdate, metal salt of tungstic acid, complex oxide of tungsten and metalloid, zirconium compound, guanidine compound , Graphite, talc, expandable graphite, and the like, of which aluminum hydroxide and talc are preferred.

The flame retardant according to the present invention is contained in an amount of 1 to 50 parts by weight, preferably 5 to 30 parts by weight, based on 100 parts by weight of the base resin of the present invention. When the content of the flame retardant is 1 to 50 parts by weight, not only excellent flame retardancy may be realized, but also excellent impact resistance and heat resistance may be ensured.

(C) Impact modifier with reactive core / shell structure

The impact modifier of the reactive core / shell structure used in the present invention has a shell-grafted structure composed of a compound having a reactive group in the core.

The core may be formed of a rubber selected from the group consisting of acrylic rubber, butadiene rubber, silicone rubber, and copolymers thereof, and the shell may be made of polymethyl (meth) acrylate having an epoxy group. Impact modifiers of this reactive core / shell structure are commercially available.

The reactive group epoxy group serves to reinforce the impact strength of the polylactic acid by allowing the impact modifier to be well dispersed in the polylactic acid through the reaction with the polylactic acid.

In addition, the impact reinforcing agent of the reactive core / shell structure of the present invention can increase the heat resistance by acting as a nucleating agent to increase the crystallization rate of the polylactic acid, and also serves to connect the crystals of the polylactic acid. In addition, the reactive group of the shell reacts with the polylactic acid to increase the melt viscosity and the melt strength of the polylactic acid, thereby preventing drips generated during combustion.

In addition, the polylactic acid having a higher melt viscosity decreases in viscosity with polycarbonate, so that polycarbonate and polylactic acid are more uniformly mixed during the extrusion and injection process, thereby improving the appearance of the molded article.

The epoxy group is preferably contained in 0.1 to 20% by weight relative to the impact modifier of the present invention. When the epoxy group is included in 0.1 to 20% by weight, it is possible to maximize the impact reinforcement effect and heat resistance improvement, and the fluidity is also significantly improved.

In addition, the impact modifier of the reactive core / shell structure according to the invention consists of a core of 30 kPa to 90 kPa and a shell of 10 kPa to 70 kPa. In the content range of the core and shell there is an excellent shock reinforcing effect.

The impact modifier of the present invention is included in 1 to 20 parts by weight, preferably 3 to 10 parts by weight based on 100 parts by weight of the base resin of the present invention. 　　 When the content of the impact modifier is included in an amount of 1 to 20 parts by weight, it is possible to maximize the impact reinforcement effect and the increase in the heat resistance, and the flowability may be improved to improve the injection moldability.

(D) other additives

The polylactic acid / polycarbonate resin composition of the present invention may further include an additive.

The additives include antibacterial agents, mold release agents, heat stabilizers, antioxidants, light stabilizers, compatibilizers, dyes, inorganic additives, surfactants, coupling agents, fillers, admixtures, colorants, stabilizers, lubricants, antistatic agents, and antistatic agents. Flame retardant, weathering agent, ultraviolet ray shielding agent, nucleating agent, adhesive agent, adhesive agent and mixtures thereof may be used.

As said antioxidant, a phenol type, a phosphide type, a thiothio type, a, or a amine type, antioxidant can be used preferably.

As said weathering agent, a benzophenone type or an amine type weathering agent can be used preferably.

As the releasing agent, fluorine-containing polymers, silicone oils, metal salts of stearic acid, metal salts of montanic acid, montanic acid ester waxes, or polyethylene waxes can be preferably used.

As the coloring agent, dyes or pigments can be preferably used.

As the ultraviolet ray shielding agent, titanium oxide or carbon black can be preferably used.

As the filler, silica, clay, calcium carbonate, calcium sulfate or glass beads may be preferably used.

As the nucleus forming agent, talc or clay may be preferably used.

The additive according to the present invention may be included in an amount of 0.1 to 30 parts by weight based on 100 parts by weight of the base resin of the present invention. When the additive is included in an amount of 0.1 to 30 parts by weight, the effect of the additive according to each use can be obtained, and excellent mechanical properties and improved surface appearance can be obtained.

The resin composition of the present invention is prepared by incorporating a polycarbonate-based resin, a polylactic acid resin, a flame retardant, and an impact modifier grafted with a compound having an epoxy group together. That is, in the present invention, it is possible to use a polycarbonate resin, a polylactic acid resin, a flame retardant, and the impact modifier at the same time, or to prepare a master batch by mixing the polylactic acid and the impact modifier.

When the master batch method is used, the fluidity of the polylactic acid having a lower viscosity than that of the polycarbonate is reduced by the impact modifier, thereby reducing the difference in viscosity between the polycarbonate and the polylactic acid.

In addition, pellets can be produced by a known method using the polylactic acid / polycarbonate resin composition of the present invention. For example, after mixing the components and additives of the present invention described above, the melt extrusion may be carried out in an extruder to produce pellets.

In addition, another embodiment of the present invention provides a molded article prepared by molding a polylactic acid / polycarbonate resin composition. The resin composition may be used for molding products in the field requiring durability, heat resistance and flame retardancy, for example, for office equipment such as automobiles, machinery parts, electrical and electronic parts, computers, and miscellaneous goods. In particular, they can be applied to housing of electronic and electronic products such as televisions, computers, printers, washing machines, cassette players, audio and game machines.

Hereinafter, preferred embodiments of the present invention will be described. However, the following examples are only preferred embodiments of the present invention, and the present invention is not limited by the following examples.

EXAMPLE

Each component used for manufacture of the polylactic acid / polycarbonate resin composition of this invention is as follows.

(A) Basic resin

(a1) polycarbonate resin

CALIBER 200-3 manufactured by LG-DOW, Korea was used. 　

(a2) polylactic acid resin

4032D manufactured by NatureWorks LLC® was used.

(B) flame retardant

In the case of phosphorus flame retardant, PX-200 manufactured by DAIHACHI, Japan was used, and in the case of inorganic flame retardant, talc was used.

(C) Impact modifier of core / shell structure

In the case of the impact reinforcing agent of the reactive core / shell structure according to the present invention METABLENE S-2200 manufactured by Mitsubishi Rayon Co., Japan was used, the core / shell impact reinforcing agent used in the comparative example was manufactured by Mitsubishi Rayon Co. METABLENE S-223A, S-2100 was used.

Example 1

Base resin comprising 64% by weight of polycarbonate resin and 36% by weight of polylactic acid resin, 15 parts by weight of phosphorus flame retardant, 2 parts by weight of inorganic flame retardant, and 1 part by weight of impact reinforcing agent of reactive core / shell structure After addition and extrusion in a temperature range of 220 to 280 ℃ in a conventional twin screw extruder, the extrudate was prepared in pellet form.

Example 2

Except for the addition of 5 parts by weight of the impact core enhancer of the reactive core / shell structure in Example 1 was prepared in the same manner as in Example 1.

Example 3

Except for the addition of 9 parts by weight of the impact core enhancer of the reactive core / shell structure in Example 1 was prepared in the same manner as in Example 1.

Comparative Example 1

In Example 1, except that 2.5 parts by weight of the core / shell shock modifier of the reactive core / shell structure and 2.5 parts by weight of the core / shell impact modifier were added in the same manner as in Example 1.

Comparative Example 2

In Example 1, 5 parts by weight of the core / shell impact modifier were added instead of 1 part by weight of the impact core of the reactive core / shell structure, and the same method as in Example 1 was performed.

Comparative Example 3

In Example 1, 9 parts by weight of the core / shell impact modifier was added instead of 1 part by weight of the impact core / shell structure of the reactive core / shell structure.

[Test Example]

The pellets prepared according to Examples 1 to 3 and Comparative Examples 1 to 3 were dried at 80 ° C. for 4 hours, and then, using an injection molding machine having an injection capacity of 6 Oz, a cylinder temperature of 220 to 280 ° C., a mold temperature of 100 ℃, the time of the shaping cycle was set to 40 seconds, ASTM dumbbell (dumbbell) test piece was injection molded to prepare a physical specimen. The prepared physical specimens were measured by the following method and the results are shown in Table 1 below.

(1) Heat deflection temperature (VST): measured according to ASTM D1525.

(2) Izod impact strength was measured according to ASTM D256A.

(3) Flame retardant: measured according to UL-94 V test.

(4) Appearance: The appearance of the molded article was visually observed.

(5) Tensile strength: measured according to ASTM D638.

(6) Bending strength: It measured according to ASTMD790.

(7) Flexural Modulus: Measured according to ASTM D790.

TABLE 1

Item unit Example Comparative example One 2 3 One 2 3  (A) Basic resin (a1) polycarbonate resin weight% 64 64 64 64 64 64 (a2) polylactic acid resin weight% 36 36 36 36 36 36 (B) flame retardant Phosphorus Flame Retardant Parts by weight 15 15 15 15 15 15 Inorganic flame retardants Parts by weight 2 2 2 2 2 2 (C) Impact modifier of core / shell structure Impact modifier with reactive core / shell structure Parts by weight One 5 9 2.5 - - Core / shell impact modifier Parts by weight - - - 2.5 5 9 Heat Deflection Temperature (18.5 kgf) ℃ 95 94 97 92 86 84 1/8 "Izod Impact Strength kgfcm / cm 9 12 18 12 12 17 Flame Retardant (UL-94) V2 V0 V1 V2 V2 fail Exterior ○ ◎ ○ △ × × The tensile strength kgf / ㎠ 660 640 610 650 650 600 Flexural strength kgf / ㎠ 980 1010 1100 1000 1050 1200 Flexural modulus kgf / ㎠ 31500 30000 29800 30000 29500 28700

Through Table 1, Examples 1 to 3 according to the present invention is not only excellent in mechanical strength compared to Comparative Examples 2 and 3 that do not include the impact reinforcing agent of the reactive core / shell structure of the present invention, heat resistance It can be seen that the flame retardancy and appearance are significantly improved.

In particular, Comparative Examples 2 and 3 in which no impact modifier of the reactive core / shell structure of the present invention is used at all are compared with Comparative Example 1 in which the impact modifier of the reactive core / shell structure of the present invention is used together with the core / shell impact modifier. It can be seen that the heat resistance and appearance characteristics are very degraded.

The present invention is not limited to the above embodiments, but may be manufactured in various forms, and a person skilled in the art to which the present invention pertains has another specific form without changing the technical spirit or essential features of the present invention. It will be appreciated that the present invention may be practiced as. It is therefore to be understood that the above-described embodiments are illustrative in all aspects and not restrictive.

Claims (9)

100 parts by weight of (A) 10 to 90% by weight of a polycarbonate-based resin, and (a2) 10 to 90% by weight of a polylactic acid resin; (B) 1 to 50 parts by weight of a flame retardant; And (C) A polylactic acid / polycarbonate resin composition comprising 1 to 20 parts by weight of an impact modifier of a reactive core / shell structure. The method of claim 1, The polylactic acid / polycarbonate resin composition of (a1) the polycarbonate resin having a weight average molecular weight of 10,000 to 35,000 g / mol. The method of claim 1, The polylactic acid resin (a2) is a polylactic acid / polycarbonate resin composition is selected from the group consisting of L-isomer, D-isomer, L, D-isomer, and combinations thereof. The method of claim 1, Wherein (a2) polylactic acid resin is a polylactic acid / polycarbonate resin composition consisting of 95 to 100% by weight of the L- isomer and 0 to 5% by weight of the D-isomer. The method of claim 1, The polylactic acid / polycarbonate resin composition of the weight average molecular weight of the (a2) polylactic acid resin is 80,000 to 300,000 g / mol. The method of claim 1, The (B) flame retardant is a polylactic acid / polycarbonate resin composition is at least one selected from the group consisting of a phosphorus flame retardant, nitrogen compound flame retardant, silicone flame retardant, and inorganic flame retardant. The method of claim 1, The impact modifier of the (C) reactive core / shell structure is a polymethyl (meth) acrylate having an epoxy group in a core formed of a rubber selected from the group consisting of acrylic rubber, butadiene rubber, silicone rubber, and copolymers thereof. A polypolylactic acid / polycarbonate resin composition in which the shell made comprises a grafted structure. The method of claim 7, wherein The epoxy group is a polylactic acid / polycarbonate resin composition is contained in 0.1 to 20% by weight relative to the impact modifier. A molded article prepared from the polylactic acid / polycarbonate resin composition according to any one of claims 1 to 8.