KR20200094959A - Thermoplastic resin composition and article produced therefrom - Google Patents

Abstract

A thermoplastic resin composition of the present invention comprises: 100 parts by weight of a thermoplastic resin including 15 to 40 wt% of a rubber-modified aromatic vinyl-based copolymer resin, 25 to 60 wt% of a polycarbonate resin, and 25 to 50 wt% of a polyester resin; 5 to 25 parts by weight of a first phosphorus compound represented by Formula 1; 0.5 to 5 parts by weight of a second phosphorus compound represented by Formula 2; and 0.1 to 2 parts by weight of chitosan having a viscosity of 1 to 50 mPa·s measured by using an acetic acid solution having a concentration of 0.5% at 20°C. The thermoplastic resin composition is excellent in flame retardancy, impact resistance, eco-friendliness, and balance of physical properties thereof.

Description

Thermoplastic resin composition and molded article formed therefrom TECHNICAL FIELD [THERMOPLASTIC RESIN COMPOSITION AND ARTICLE PRODUCED THEREFROM}

The present invention relates to a thermoplastic resin composition and a molded article formed therefrom. More specifically, the present invention relates to a thermoplastic resin composition excellent in flame retardancy, impact resistance, eco-friendliness, and balance of properties thereof, and a molded article formed therefrom.

Thermoplastic resin compositions including rubber-modified aromatic vinyl-based copolymer resins, polycarbonate resins, and flame retardants are excellent in impact resistance, flame retardancy, and processability, and are therefore resistant to heat-generating electrical/electronic product housings and other office equipment. /Useful as an exterior material.

However, as interest in environmental issues emerges, regulations on existing halogen-based flame retardants are gradually strengthening, and thus, application of non-halogen-based flame retardants is required to use the thermoplastic resin composition as an eco-friendly material. However, when a non-halogen-based flame retardant is applied to a thermoplastic resin composition containing a rubber-modified aromatic vinyl-based copolymer resin, there is a problem in that the flame retardancy is significantly lowered compared to the application of the halogen-based flame retardant. In addition, in order to improve the flame retardancy of the thermoplastic resin composition, when an excessive amount of the flame retardant is used, there is a concern that impact resistance and the like may decrease.

Therefore, there is a need to develop a thermoplastic resin composition excellent in flame retardancy, impact resistance, environment-friendliness, and balance of properties thereof.

The background technology of the present invention is disclosed in US Patent No. 5,061,745 and the like.

It is an object of the present invention to provide a thermoplastic resin composition excellent in flame retardancy, impact resistance, environmental friendliness, and balance of properties thereof.

Another object of the present invention is to provide a molded article formed from the thermoplastic resin composition.

All of the above and other objects of the present invention can be achieved by the present invention described below.

1. One aspect of the present invention relates to a thermoplastic resin composition. The thermoplastic resin composition includes: 100 parts by weight of a thermoplastic resin including 15 to 40% by weight of a rubber-modified aromatic vinyl-based copolymer resin, 25 to 60% by weight of a polycarbonate resin, and 25 to 50% by weight of a polyester resin; 5 to 25 parts by weight of a first phosphorus compound represented by Formula 1 below; 0.5 to 5 parts by weight of a second phosphorus compound represented by Formula 2 below; And 0.1 to 2 parts by weight of chitosan having a viscosity of 1 to 50 mPa·s measured using an acetic acid solution having a concentration of 0.5% at 20° C.:

[Formula 1]

In Formula 1, R ₁ , R ₂ , R ₃ and R ₄ are each independently a hydrogen atom, a C6-C20 aryl group, or a C6-C20 aryl substituted with a C1-C10 alkyl group Group, and m is 1 or 2;

[Formula 2]

In Formula 2, R ₅ , R ₆ , R ₇ and R ₈ are each independently a hydrogen atom, a C6-C20 aryl group, or a C6-C20 aryl substituted with a C1-C10 alkyl group Group, and n is an integer of 0 to 2.

2. In the first embodiment, the rubber-modified aromatic vinyl-based copolymer resin may include a rubber-modified vinyl-based graft copolymer and an aromatic vinyl-based copolymer resin.

3. In the above 1 or 2 embodiments, the rubber-modified vinyl-based graft copolymer may be obtained by graft polymerization of a monomer mixture including an aromatic vinyl-based monomer and a vinyl cyanide-based monomer in a rubbery polymer.

4. In the above 1 to 3 embodiments, the polyester resin is polyethylene terephthalate (PET), polybutylene terephthalate (PBT), polyethylene naphthalate (PEN) and polytrimethylene terephthalate (PTT), polycyclohex It may contain one or more of silenedimethylene terephthalate (PCT).

5. In the above 1 to 4 embodiments, the chitosan may have a degree of deacetylation of 75 to 85%.

6. In the above 1-5 embodiments, the weight ratio of the first phosphorus compound and the second phosphorus compound may be 4:1 to 10:1.

7. In the above 1 to 6 embodiments, the sum of the first phosphorus compound and the second phosphorus compound may be 10 to 20 parts by weight based on 100 parts by weight of the thermoplastic resin composition.

8. In the above 1 to 7 embodiments, the weight ratio of the first and second phosphorus-based compounds and the chitosan may be 10:1 to 40:1.

9. In the above embodiments 1 to 8, the thermoplastic resin composition may have a flame retardancy of V-0 of a 2 mm-thick injection specimen measured by the UL-94 vertical test method.

10. In the 1 to 9 embodiments, the thermoplastic resin composition may have a notched Izod impact strength of 8 to 20 kgf·cm/cm of a 1/4" thick specimen measured according to ASTM D256.

11. Another aspect of the present invention relates to a molded article. The molded article is characterized in that it is formed from the thermoplastic resin composition according to any one of the above 1 to 10.

The present invention has the effect of the invention of providing a thermoplastic resin composition excellent in flame retardancy, impact resistance, environmental friendliness, and balance of properties thereof, and a molded article formed therefrom.

Hereinafter, the present invention will be described in detail.

The thermoplastic resin composition according to the present invention includes (A) a rubber-modified aromatic vinyl-based copolymer resin; (B) polycarbonate resin; (C) polyester resin; (D) a phosphorus compound including a first phosphorus compound and a second phosphorus compound; And (E) chitosan.

In the present specification, "a to b" representing a numerical range is defined as "≥a and ≤b".

(A) Rubber-modified aromatic vinyl copolymer resin

The rubber-modified aromatic vinyl-based copolymer resin according to an embodiment of the present invention may include (A1) a rubber-modified vinyl-based graft copolymer and (A2) an aromatic vinyl-based copolymer resin.

(A1) Rubber-modified vinyl-based graft copolymer

The rubber-modified vinyl-based graft copolymer according to an embodiment of the present invention may be obtained by graft polymerization of a monomer mixture including an aromatic vinyl-based monomer and a vinyl cyanide-based monomer in a rubbery polymer. For example, the rubber-modified vinyl-based graft copolymer can be obtained by graft-polymerizing a monomer mixture including an aromatic vinyl-based monomer and a vinyl cyanide-based monomer in a rubbery polymer. If necessary, the monomer mixture has processability and Graft polymerization can be performed by further including a monomer imparting heat resistance. The polymerization can be performed by a known polymerization method such as emulsion polymerization and suspension polymerization. In addition, the rubber-modified vinyl-based graft copolymer may form a core (rubber polymer)-shell (copolymer of a monomer mixture) structure, but is not limited thereto.

In a specific embodiment, the rubber polymer includes a diene-based rubber such as polybutadiene, poly(styrene-butadiene), and poly(acrylonitrile-butadiene), and a saturated rubber hydrogenated to the diene-based rubber, isoprene rubber, and 2 to carbon atoms. A 10 alkyl (meth)acrylate rubber, a copolymer of an alkyl (meth)acrylate having 2 to 10 carbon atoms and styrene, an ethylene-propylene-diene monomer terpolymer (EPDM), and the like can be exemplified. These may be applied alone or in combination of two or more. For example, diene rubber, (meth)acrylate rubber, and the like can be used, and specifically, butadiene rubber, butyl acrylate rubber, and the like can be used.

In specific embodiments, the rubbery polymer (rubber particles) may have an average particle size of 0.05 to 6 µm, for example, 0.15 to 4 µm, and specifically 0.25 to 3.5 µm. Within the above range, the thermoplastic resin composition may have excellent impact resistance and appearance characteristics. Here, the average particle size (z-average) of the rubbery polymer (rubber particle) can be measured using a light scattering method in a latex state. Specifically, the rubbery polymer latex is filtered through a mesh to remove coagulation generated during the rubbery polymer polymerization, and a solution of 0.5 g of latex and 30 ml of distilled water is poured into a 1,000 ml flask and filled with distilled water to prepare a sample. , 10 ml of a sample is transferred to a quartz cell, and the average particle size of the rubbery polymer can be measured with a 　 light scattering particle size meter (malvern, nano-zs).

In a specific embodiment, the content of the rubbery polymer may be 20 to 70% by weight, for example, 25 to 60% by weight of the total 100% by weight of the rubber-modified vinyl-based graft copolymer, and the monomer mixture (aromatic vinyl-based monomer and The content of vinyl cyanide-based monomer) may be 30 to 80% by weight, for example, 40 to 75% by weight of the total 100% by weight of the rubber-modified vinyl-based graft copolymer. Within the above range, the thermoplastic resin composition may have excellent impact resistance and appearance characteristics.

In a specific embodiment, the aromatic vinyl-based monomer may be graft copolymerized with the rubbery polymer, and includes styrene, α-methylstyrene, β-methylstyrene, p-methylstyrene, pt-butylstyrene, ethylstyrene, vinylxylene, Monochlorostyrene, dichlorostyrene, dibromostyrene, vinyl naphthalene, etc. can be illustrated. These can be used alone or in combination of two or more. The content of the aromatic vinyl-based monomer may be 10 to 90% by weight, for example, 40 to 90% by weight of 100% by weight of the monomer mixture. In the above range, the processability and impact resistance of the thermoplastic resin composition may be excellent.

In a specific embodiment, the vinyl cyanide-based monomer is copolymerizable with the aromatic vinyl-based, and includes acrylonitrile, methacrylonitrile, ethacrylonitrile, phenylacrylonitrile, α-chloroacrylonitrile, fumaronitrile, etc. Can be illustrated. These can be used alone or in combination of two or more. For example, acrylonitrile, methacrylonitrile, etc. can be used. The content of the vinyl cyanide-based monomer may be 10 to 90% by weight, for example, 10 to 60% by weight of 100% by weight of the monomer mixture. Within the above range, the thermoplastic resin composition may have excellent chemical resistance and mechanical properties.

In specific embodiments, as the monomer for imparting the processability and heat resistance, (meth)acrylic acid, maleic anhydride, N-substituted maleimide, and the like may be exemplified, but are not limited thereto. When using a monomer for imparting the processability and heat resistance, the content may be 15% by weight or less, for example, 0.1 to 10% by weight of 100% by weight of the monomer mixture. In the above range, it is possible to impart processability and heat resistance to the thermoplastic resin composition without deteriorating other physical properties.

In a specific embodiment, the rubber-modified vinyl-based graft copolymer is a copolymer (g-ABS), in which a styrene monomer as an aromatic vinyl-based compound and an acrylonitrile monomer as a vinyl cyanide-based compound are grafted to a butadiene-based rubbery polymer, butadiene-based A copolymer (g-MBS) grafted with methyl methacrylate as a monomer copolymerizable with styrene monomer, which is an aromatic vinyl compound to a rubber polymer, and styrene monomer and vinyl cyanide, which are an aromatic vinyl compound to a butyl acrylate rubber polymer An acrylate-styrene-acrylonitrile graft copolymer (g-ASA), which is a copolymer grafted with the compound acrylonitrile monomer, may be exemplified.

In a specific embodiment, the rubber-modified vinyl-based graft copolymer may be included in an amount of 20 to 60% by weight, for example, 22 to 50% by weight of 100% by weight of the total rubber-modified aromatic vinyl-based copolymer resin. Within the above range, the thermoplastic resin composition may have excellent impact resistance, fluidity (molding processability), appearance characteristics, and balance of physical properties thereof.

(A2) Aromatic vinyl copolymer resin

The aromatic vinyl-based copolymer resin according to an embodiment of the present invention may be an aromatic vinyl-based copolymer resin used in a conventional rubber-modified aromatic vinyl-based copolymer resin. For example, the aromatic vinyl-based copolymer resin may be a polymer of a monomer mixture including an aromatic vinyl-based monomer and a monomer copolymerizable with the aromatic vinyl-based monomer.

In a specific embodiment, the aromatic vinyl-based copolymer resin may be obtained by mixing an aromatic vinyl-based monomer and a monomer copolymerizable with an aromatic vinyl-based monomer, and then polymerizing the same, and the polymerization is emulsion polymerization, suspension polymerization, bulk polymerization, etc. It can be carried out by a known polymerization method of.

In a specific embodiment, the aromatic vinyl-based monomer is styrene, α-methylstyrene, β-methylstyrene, p-methylstyrene, pt-butylstyrene, ethylstyrene, vinylxylene, monochlorostyrene, dichlorostyrene, dibromostyrene , Vinyl naphthalene, etc. can be used. These may be applied alone or in combination of two or more. The content of the aromatic vinyl-based monomer may be 20 to 90% by weight, for example, 30 to 80% by weight, based on 100% by weight of the total aromatic vinyl-based copolymer resin. Within the above range, the thermoplastic resin composition may have excellent impact resistance and fluidity.

In specific embodiments, the monomer copolymerizable with the aromatic vinyl-based monomer may include at least one of a vinyl cyanide-based monomer and an alkyl (meth)acrylic monomer. For example, it may be a vinyl cyanide-based monomer or a vinyl cyanide-based monomer and an alkyl (meth)acrylic monomer, specifically, a vinyl cyanide-based monomer.

In a specific embodiment, the vinyl cyanide monomer may include acrylonitrile, methacrylonitrile, ethacrylonitrile, phenylacrylonitrile, α-chloroacrylonitrile, fumaronitrile, etc., but is not limited thereto. Does not. These can be used alone or in combination of two or more. For example, acrylonitrile, methacrylonitrile, etc. can be used.

In specific embodiments, the alkyl (meth) acrylic monomer may be exemplified by (meth) acrylic acid and/or an alkyl (meth) acrylate having 1 to 10 carbon atoms. These can be used alone or in combination of two or more. For example, methyl methacrylate, methyl acrylate, etc. can be used.

In a specific embodiment, the content of the monomer copolymerizable with the aromatic vinyl-based monomer may be 10 to 80% by weight, for example, 20 to 70% by weight, based on the total 100% by weight of the aromatic vinyl-based copolymer resin. Within the above range, the thermoplastic resin composition may have excellent impact resistance and fluidity.

In a specific embodiment, the aromatic vinyl-based copolymer resin may have a weight average molecular weight (Mw) of 10,000 to 300,000 g/mol, for example, 15,000 to 150,000 g/mol, as measured by gel permeation chromatography (GPC). Within the above range, the thermoplastic resin composition may have excellent mechanical strength and moldability.

In a specific embodiment, the aromatic vinyl-based copolymer resin may be included in 40 to 80% by weight, for example, 50 to 78% by weight of 100% by weight of the total rubber-modified aromatic vinyl-based copolymer resin. Within the above range, the thermoplastic resin composition may have excellent impact resistance and fluidity (molding processability).

In a specific embodiment, the rubber-modified aromatic vinyl-based copolymer resin (A) is a thermoplastic resin (rubber-modified aromatic vinyl-based copolymer resin (A), polycarbonate resin (B) and polyester resin (C)) 100% by weight of , 15 to 40% by weight, for example, 15 to 35% by weight, specifically 15 to 30% by weight may be included. When the content of the rubber-modified aromatic vinyl-based copolymer resin is less than 15% by weight, there is a concern that the impact resistance of the thermoplastic resin composition may decrease, and when it exceeds 50% by weight, there is a concern that flame retardancy, fluidity, etc. .

(B) polycarbonate resin

As the polycarbonate resin according to an embodiment of the present invention, a polycarbonate resin used in a conventional thermoplastic resin composition may be used. For example, an aromatic polycarbonate resin produced by reacting diphenols (aromatic diol compounds) with precursors such as phosgene, halogen formate, and carbonic acid diester can be used.

In a specific embodiment, the diphenols include 4,4'-biphenol, 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, 2,2-bis(3,5-dichloro-4-hydroxyphenyl) Propane and the like may be exemplified, but are not limited thereto. For example, 2,2-bis(4-hydroxyphenyl)propane, 2,2-bis(3,5-dichloro-4-hydroxyphenyl)propane, or 1,1-bis(4-hydroxyphenyl) ) Cyclohexane can be used, specifically, 2,2-bis(4-hydroxyphenyl)propane called bisphenol-A can be used.

In an embodiment, the polycarbonate resin may be used having a branched chain, for example, 0.05 to 2 mol% of trivalent or higher polyfunctional compound, specifically, 3 with respect to the entire diphenols used for polymerization. It is also possible to use branched polycarbonate resins prepared by adding compounds having a phenol group or more.

In embodiments, the polycarbonate resin may be used in the form of a homo polycarbonate resin, copolycarbonate resin or a blend thereof. In addition, the polycarbonate resin may be partially or wholly substituted with an aromatic polyester-carbonate resin obtained by polymerization reaction in the presence of an ester precursor, such as a bifunctional carboxylic acid.

In a specific embodiment, the polycarbonate resin may have a weight average molecular weight (Mw) measured by gel permeation chromatography (GPC) of 10,000 to 50,000 g/mol, for example, 15,000 to 40,000 g/mol. Within the above range, the fluidity (processability) of the thermoplastic resin composition may be excellent.

In a specific embodiment, the polycarbonate resin (B) is a thermoplastic resin (rubber-modified aromatic vinyl copolymer resin (A), polycarbonate resin (B) and polyester resin (C)) of 100% by weight, 25 to 60% by weight %, for example, 30 to 50% by weight, specifically 35 to 50% by weight. When the content of the polycarbonate resin is less than 25% by weight, flame retardancy and impact resistance of the thermoplastic resin composition may be deteriorated, and when it exceeds 60% by weight, fluidity and the like may be deteriorated.

(C) Polyester resin

As the polyester resin according to an embodiment of the present invention, a polyester resin used in a conventional thermoplastic resin composition may be used. For example, the polyester resin is a dicarboxylic acid component, terephthalic acid (TPA), isophthalic acid (IPA), 1,2-naphthalene dicarboxylic acid, 1,4-naphthalene dicarboxylic acid. Acid, 1,5-naphthalene dicarboxylic acid, 1,6-naphthalene dicarboxylic acid, 1,7-naphthalene dicarboxylic acid, 1,8-naphthalene dicarboxylic acid, 2,3-naphthalene dicarboxylic acid Aromatic dicarboxylic acids such as carboxylic acid, 2,6-naphthalene dicarboxylic acid, and 2,7-naphthalenedicarboxylic acid, dimethyl terephthalate (DMT), dimethyl isophthalate, dimethyl- 1,2-naphthalate, dimethyl-1,5-naphthalate, dimethyl-1,7-naphthalate, dimethyl-1,7-naphthalate, dimethyl-1,8-naphthalate, dimethyl-2,3-na As diol components, such as aromatic dicarboxylate such as phthalate, dimethyl-2,6-naphthalate, dimethyl-2,7-naphthalate, etc., ethylene glycol, 1,2-propylene glycol, 1,3-propylene Glycol, 2,2-dimethyl-1,3-propanediol, 1,3-butanediol, 1,4-butanediol, 1,5-pentanediol, 1,5-pentanediol, 1,6-hexanediol, cyclic alkyl It can be obtained by polycondensing rendiol or the like.

In a specific embodiment, the polyester resin is polyethylene terephthalate (PET), polybutylene terephthalate (PBT), polyethylene naphthalate (PEN) and polytrimethylene terephthalate (PTT), polycyclohexylenedimethylene terephthalate ( PCT) may include one or more.

In a specific example, the polyester resin of the present invention may have an intrinsic viscosity [η] of 0.5 to 1.5 dl/g, for example, 0.6 to 1.3 dl/g, measured using an o-chlorophenol solvent at 25°C. . Within the above range, the thermoplastic resin composition may have excellent flame retardancy and mechanical properties.

In a specific embodiment, the polyester resin (C) is a thermoplastic resin (rubber-modified aromatic vinyl copolymer resin (A), polycarbonate resin (B) and polyester resin (C)) 100% by weight, 25 to 50% by weight %, for example, 30 to 50% by weight, specifically 35 to 45% by weight. When the content of the polyester resin is less than 25% by weight, there is a concern that the flame retardancy and fluidity (processability) of the thermoplastic resin composition may decrease, and when it exceeds 50% by weight, there is a concern that impact resistance and the like may decrease.

(D) phosphorus compound

The phosphorus compound of the present invention is applied together with chitosan to improve the impact resistance, flame retardancy, environment-friendliness, and balance of properties of the thermoplastic resin composition. (D1) the first phosphorus compound and (D2) the second phosphorus compound Mix and use compounds.

(D1) first phosphorus compound

As the first phosphorus compound, a compound represented by the following Formula 1 may be used.

[Formula 1]

In Formula 1, R ₁ , R ₂ , R ₃ and R ₄ are each independently a hydrogen atom, a C6-C20 aryl group, or a C6-C20 aryl substituted with a C1-C10 alkyl group Group, and m is 1 or 2.

In a specific embodiment, the first phosphorus compound may be bisphenol-A bis (diphenyl phosphate) or the like.

In a specific example, the first phosphorus compound (D1) is based on 100 parts by weight of the thermoplastic resin (rubber-modified aromatic vinyl-based copolymer resin (A), polycarbonate resin (B) and polyester resin (C)), 5 It may be included in to 25 parts by weight, for example, 10 to 20 parts by weight. When the content of the first phosphorus compound (D1) is less than 5 parts by weight based on 100 parts by weight of the thermoplastic resin, the flame retardancy of the thermoplastic resin composition may be reduced, and when it exceeds 25 parts by weight, the resistance of the thermoplastic resin composition There is a concern that impact resistance, heat resistance, releasability, and the like may decrease.

(D2) second phosphorus compound

As the second phosphorus compound, a compound represented by Formula 2 below may be used.

[Formula 2]

In Formula 2, R ₅ , R ₆ , R ₇ and R ₈ are each independently a hydrogen atom, a C6-C20 aryl group, or a C6-C20 aryl substituted with a C1-C10 alkyl group Group, and n is an integer of 0 to 2.

In a specific embodiment, as the second phosphorus compound, resorcinol di(bis-2,6-dimethylphenyl)phosphate, triphenyl phosphate, a combination thereof, and the like may be used.

In a specific embodiment, the second phosphorus-based compound (D2) is 0.5 based on 100 parts by weight of the thermoplastic resin (rubber-modified aromatic vinyl-based copolymer resin (A), polycarbonate resin (B) and polyester resin (C)). It may be included in to 5 parts by weight, for example, 1 to 4 parts by weight. When the content of the second phosphorus compound (D2) is less than 0.5 parts by weight based on 100 parts by weight of the thermoplastic resin, there is a possibility that the flame retardancy of the thermoplastic resin composition may be lowered, and when it exceeds 5 parts by weight, the resistance of the thermoplastic resin composition There is a concern that impact resistance, heat resistance, releasability, and the like may decrease.

In a specific embodiment, the weight ratio of the first phosphorus compound and the second phosphorus compound (first phosphorus compound: second phosphorus compound) may be 4:1 to 10:1, for example, 6:1 to 8:1. . In the above range, flame retardancy, impact resistance, and balance of physical properties of the thermoplastic resin composition may be more excellent.

In a specific embodiment, the content of the phosphorus compound (the first phosphorus compound and the second phosphorus compound) may be 10 to 20 parts by weight, for example, 12 to 20 parts by weight, based on 100 parts by weight of the thermoplastic resin composition. In the above range, flame retardancy, impact resistance, and balance of physical properties of the thermoplastic resin composition may be more excellent.

(E) chitosan

The chitosan of the present invention is applied together with the phosphorus compound to improve the impact resistance, flame retardancy, environmental friendliness, and balance of properties of the thermoplastic resin composition, and deacetylates chitin contained in crabs, crayfish, and shrimp shells. You can use what you have obtained.

In a specific embodiment, the chitosan may have a viscosity of 1 to 50 mPa·s, for example, 5 to 20 mPa·s, measured using an acetic acid solution having a concentration of 0.5% at 20°C. When the viscosity of the chitosan is out of the above range, there is a concern that flame retardancy, impact resistance, etc. may be deteriorated.

In an embodiment, the chitosan may be a powder or flake type having a deacetylation value of 75 to 85%. For example, chitosan having a degree of deacetylation of 75 to 85% can be prepared by reacting dried chitin powder with an alkali concentration of 40 to 60% and a reaction temperature of 100 to 180°C for 2 to 4 hours. Within the above range, the thermoplastic resin composition may have excellent flame retardancy and impact resistance.

In a specific embodiment, the chitosan (E) is 0.1 to 2 parts by weight based on 100 parts by weight of the thermoplastic resin (rubber-modified aromatic vinyl-based copolymer resin (A), polycarbonate resin (B) and polyester resin (C)) It may be included in parts, for example 0.5 to 1 part by weight. If the content of chitosan is less than 0.1 parts by weight based on 100 parts by weight of the thermoplastic resin, there is a risk that the flame retardancy and impact resistance of the thermoplastic resin composition may be reduced, and if it exceeds 2 parts by weight, the flame retardancy of the thermoplastic resin composition, resistance There is a possibility that the impact property and the like may be deteriorated.

In a specific embodiment, the weight ratio (D:E) of the phosphorus compound (D(D1+D2)) and the chitosan (E) may be 10:1 to 40:1, for example 15:1 to 35:1. . In the above range, flame retardancy, impact resistance, and balance of physical properties of the thermoplastic resin composition may be more excellent.

The thermoplastic resin composition according to an embodiment of the present invention may further include additives included in a conventional thermoplastic resin composition. As the additive, a lubricant, a nucleating agent, a stabilizer, a release agent, a pigment, a dye, a mixture thereof, and the like may be exemplified, but are not limited thereto. When using the additive, the content may be 0.001 to 40 parts by weight, for example, 0.1 to 10 parts by weight, based on 100 parts by weight of the thermoplastic resin.

The thermoplastic resin composition according to an embodiment of the present invention may be in the form of pellets obtained by mixing the above constituents and melt-extruding at 200 to 280°C, for example, 210 to 250°C using a conventional twin screw extruder.

In a specific example, the thermoplastic resin composition may have a flame retardancy of V-0 of a 2 mm-thick injection specimen measured by the UL-94 vertical test method.

In an embodiment, the thermoplastic resin composition may have a notched Izod impact strength of 8 to 20 kgf·cm/cm of a 1/4" thick specimen measured according to ASTM D256.

The molded article according to the present invention is formed from the thermoplastic resin composition. The thermoplastic resin composition may be manufactured in the form of pellets, and the manufactured pellets may be manufactured into various molded articles (products) through various molding methods such as injection molding, extrusion molding, vacuum molding, and casting molding. Such a molding method is well known by those of ordinary skill in the field to which the present invention belongs. The molded article is excellent in hydrolysis resistance, flame retardancy, impact resistance, and balance of properties thereof, and is useful as an interior/exterior material for electric/electronic products, an interior/exterior material for automobiles, and an exterior material for construction.

Hereinafter, the present invention will be described in more detail through examples, but these examples are for the purpose of description only and should not be construed as limiting the invention.

Example

Hereinafter, specifications of each component used in Examples and Comparative Examples are as follows.

(A) Rubber-modified aromatic vinyl copolymer resin

The following (A1) rubber-modified aromatic vinyl-based graft copolymer 23% by weight and (A2) aromatic vinyl-based copolymer resin 77% by weight were mixed and used.

(A1) Rubber-modified vinyl-based graft copolymer

A core-shell type graft prepared by graft copolymerization of 42% by weight of styrene and acrylonitrile (styrene/acrylonitrile: 75% by weight/25% by weight) to 58% by weight of a butadiene rubber having an average particle size of 0.3 μm Copolymer (g-ABS) was used.

(A2) Aromatic vinyl copolymer resin

A resin prepared by polymerizing 72% by weight of styrene and 28% by weight of acrylonitrile (weight average molecular weight: 135,000 g/mol) was used.

(B) polycarbonate resin

A bisphenol-A type polycarbonate resin having a weight average molecular weight (Mw) of 22,000 g/mol was used.

(C) Polyester resin

Polyethylene terephthalate (PET) having an intrinsic viscosity [η] of 1.0 dl/g measured using an o-chlorophenol solvent at 25°C was used.

(D) phosphorus compound

(D1) Bisphenol-A diphosphate (manufacturer: DAIHACHI, product name: CR-741) was used.

(D2) Resorcinol di (bis-2,6-dimethylphenyl) phosphate (resorcinol di (bis-2,6-dimethylphenyl) phosphate, manufacturer: DAIHACHI, product name: PX-200) was used.

(E) chitosan

(E1) Chitosan (manufacturer: TCI, product name: C2395, viscosity: 5 to 20 mPa·s) was used.

(E2) Chitosan (manufacturer: TCI, product name C0831, viscosity: 200 to 600 mPa·s) was used.

Example 1 to 5 and Comparative example 1 to 7

Each of the above constituents was added in an amount as shown in Tables 1 and 2 below, and then extruded at 210°C to prepare a pellet. Extrusion was performed using a twin-screw extruder with L/D=36 and diameter of 45 mm, and the produced pellets were dried at 80°C for 2 hours or more, and then injected in a 6 Oz injection machine (molding temperature 230°C, mold temperature: 60°C) Was prepared. The prepared specimens were evaluated for physical properties by the following method, and the results are shown in Tables 1 and 2.

Method for measuring properties

(1) Flame retardancy: According to the UL-94 vertical test method, the flame retardancy of a 2 mm-thick injection specimen was measured.

(2) Notched Izod impact strength (unit: kgf·cm/cm): According to ASTM D256, the notched Izod impact strength of a 1/4" thick specimen was measured.

Example One 2 3 4 5 (A) (% by weight) 19 19 19 19 19 (B) (% by weight) 49 49 49 49 49 (C) (% by weight) 32 32 32 32 32 (D1) (parts by weight) 13.6 15 15.4 15 15 (D2) (parts by weight) 3.4 2 1.6 2 2 (E1) (parts by weight) 0.7 0.7 0.7 0.5 1.0 (E2) (parts by weight) - - - - - Flame retardancy V-0 V-0 V-0 V-0 V-0 Notch Izod impact strength 8.5 8.3 8.1 8.5 8.4

Comparative example One 2 3 4 5 6 7 (A) (% by weight) 19 19 19 19 19 19 19 (B) (% by weight) 49 49 49 49 49 49 49 (C) (% by weight) 32 32 32 32 32 32 32 (D1) (parts by weight) 17 - 25 0.1 15 15 15 (D2) (parts by weight) - 17 0.1 25 2 2 2 (E1) (parts by weight) 0.7 0.7 0.7 0.7 0.01 - 3 (E2) (parts by weight) - - - - - 0.7 - Flame retardancy V-2 V-2 V-1 V-1 V-2 V-1 V-2 Notch Izod impact strength 5.1 4.9 3.2 3.1 6.2 7.2 7.5

From the above results, it can be seen that the thermoplastic resin composition of the present invention has excellent flame retardancy, impact resistance, and balance of properties thereof, and is environmentally friendly by applying a phosphorus compound and chitosan.

On the other hand, in the case of Comparative Example 1 in which the second phosphorus compound was not applied, it can be seen that the flame retardancy and impact resistance were significantly reduced, and in the case of Comparative Example 2 in which the first phosphorus compound was not applied, the flame retardance and impact resistance were significantly In the case of Comparative Example 3 in which an excess of the first phosphorus compound was applied and a small amount of the second phosphorus compound was applied, it was found that the impact resistance was greatly reduced and the flame retardance was decreased, and an excessive amount of the second phosphorus compound was applied. And, in the case of Comparative Example 4 in which a small amount of the first phosphorus compound was applied, it can be seen that the impact resistance is greatly reduced and the flame retardance is decreased. In the case of Comparative Example 5 in which a small amount of chitosan was applied and Comparative Example 7 in which an excessive amount of chitosan was applied, it can be seen that the flame retardancy was greatly decreased and the impact resistance was decreased. In addition, in the case of Comparative Example 6 to which chitosan (E2) having a viscosity outside the scope of the present invention is applied, it can be seen that flame retardancy and impact resistance are lowered.

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 considered to be included in the scope of the present invention.

Claims (11)

100 parts by weight of a thermoplastic resin including 15 to 40% by weight of a rubber-modified aromatic vinyl-based copolymer resin, 25 to 60% by weight of a polycarbonate resin, and 25 to 50% by weight of a polyester resin;
5 to 25 parts by weight of a first phosphorus compound represented by Formula 1 below;
0.5 to 5 parts by weight of a second phosphorus compound represented by Formula 2 below; And
A thermoplastic resin composition comprising: 0.1 to 2 parts by weight of chitosan having a viscosity of 1 to 50 mPa·s measured using an acetic acid solution having a concentration of 0.5% at 20°C:
[Formula 1]

In Formula 1, R ₁ , R ₂ , R ₃ and R ₄ are each independently a hydrogen atom, a C6-C20 aryl group, or a C6-C20 aryl substituted with a C1-C10 alkyl group Group, and m is 1 or 2;
[Formula 2]

In Formula 2, R ₅ , R ₆ , R ₇ and R ₈ are each independently a hydrogen atom, a C6-C20 aryl group, or a C6-C20 aryl substituted with a C1-C10 alkyl group Group, and n is an integer of 0 to 2.
The thermoplastic resin composition according to claim 1, wherein the rubber-modified aromatic vinyl-based copolymer resin comprises a rubber-modified vinyl-based graft copolymer and an aromatic vinyl-based copolymer resin.
The thermoplastic resin composition of claim 2, wherein the rubber-modified vinyl-based graft copolymer is graft-polymerized by a monomer mixture including an aromatic vinyl-based monomer and a vinyl cyanide-based monomer on a rubbery polymer.
The method of claim 1, wherein the polyester resin is polyethylene terephthalate (PET), polybutylene terephthalate (PBT), polyethylene naphthalate (PEN) and polytrimethylene terephthalate (PTT), and polycyclohexylenedimethylene terephthalate. A thermoplastic resin composition comprising at least one of phthalate (PCT).
The thermoplastic resin composition of claim 1, wherein the chitosan has a deacetylation degree of 75 to 85%.
The thermoplastic resin composition of claim 1, wherein the weight ratio of the first phosphorus compound and the second phosphorus compound is 4:1 to 10:1.
The thermoplastic resin composition of claim 1, wherein the sum of the first phosphorus compound and the second phosphorus compound is 10 to 20 parts by weight based on 100 parts by weight of the thermoplastic resin composition.
The thermoplastic resin composition of claim 1, wherein a weight ratio of the sum of the first and second phosphorus compounds and the chitosan is 10:1 to 40:1.
The thermoplastic resin composition according to claim 1, wherein the thermoplastic resin composition has a flame retardancy of V-0 of a 2 mm-thick injection specimen measured by UL-94 vertical test method.
The thermoplastic resin composition of claim 1, wherein the thermoplastic resin composition has a notched Izod impact strength of a 1/4" thick specimen measured according to ASTM D256 of 8 to 20 kgf·cm/cm.
A molded article formed from the thermoplastic resin composition according to any one of claims 1 to 10.