KR100877295B1 - Scratch-resistant flameproof thermoplastic resin composition - Google Patents

Abstract

A scratch-resistant thermoplastic resin composition is provided to ensure excellent fire retardancy, transparency and scratch resistance and to increase the fluidity. A scratch-resistant thermoplastic resin composition comprises a base resin 100.0 parts by weight, a phenol resin 1-20 parts by weight and a flame retardant 1-50 parts by weight. The base resin consists of (A) polycarbonate-based resin 20-80 parts by weight and (B) methacrylate-based resin 20-80 parts by weight. The methacrylate-based resin (B) is the copolymers of the monofunctional unsaturated monomer 0-50 weight% and methylmethacrylate 50-100 weight%. The phenol resin (C) is one or their mixture selected from the group consisting of a phenol novolac resin and a phenol epoxy novolac resin.

Description

Scratch-Resistant Flameproof Thermoplastic Resin Composition

Field of invention

The present invention relates to a scratch flame retardant thermoplastic resin composition. More specifically, the present invention relates to a thermoplastic resin composition having excellent scratch resistance and flame retardancy made of a polycarbonate resin, a polymethyl methacrylate, a phenol resin, and a flame retardant.

Background of the Invention

Electric and electronic products require various characteristics of resins according to the trend of larger size, specialization and light weight. In particular, as the appearance of the exterior material is more important, the scratch resistance of the resin is required, and the application of the flame retardant resin is further required due to the safety issue against fire. However, acrylic resins are highly flammable and have difficulty in producing flame retardant resins, and thus their use as flame retardant resins is limited.

In order to achieve scratch resistance and flame resistance, there is a method of alloying a polycarbonate (PC) resin and a methacrylate resin. In this study, polymethyl methacrylate (PMMA) was added to polycarbonate (PC) resin.

Polycarbonate resin is a resin that is very excellent in mechanical strength and excellent in transparency, thermal stability, self-extinguishing, dimensional stability and the like widely used in electric and electronic products, automotive parts, it is easy to achieve flame retardancy with a conventional flame retardant. However, since the scratch resistance of polycarbonate itself is not good at around the pencil hardness B, there is a problem in that the polycarbonate resin cannot achieve good scratch resistance.

On the other hand, in the case of polymethyl methacrylate resin having excellent scratch resistance, the pencil hardness of the resin itself is good as about 3H, but has a disadvantage that it is very difficult to achieve flame retardancy with the existing flame retardant. Therefore, when blending PC resin and PMMA resin, the phenol resin was blended with a char forming agent to improve the flame retardant properties.

An object of the present invention is to provide a scratch-resistant flame retardant thermoplastic resin composition.

Another object of the present invention is to provide a scratch-resistant flame-retardant thermoplastic resin composition not only excellent in flame retardancy, but also excellent in transparency and scratch resistance.

Another object of the present invention is to provide a scratch-resistant flame retardant thermoplastic resin composition to which a phenol novolak resin is added to improve flame retardancy.

Another object of the present invention is to provide a plastic molded article produced using the composition.

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

Summary of the Invention

The scratch-resistant flame retardant thermoplastic resin composition of the present invention (A) 20 to 80 parts by weight of a polycarbonate resin; And (B) 20 to 80 parts by weight of a polymethyl methacrylate resin; 1 to 20 parts by weight of (C) phenol resin based on 100 parts by weight of the basic resin; And (D) 1 to 50 parts by weight of a flame retardant; It characterized by comprising a, the present invention includes a molded article extruded the thermoplastic resin composition.

Details of the present invention will be described in detail below.

Detailed Description of the Invention

(A) polycarbonate resin

The polycarbonate resin (A) according to the present invention may be prepared by reacting diphenols represented by the following formula (1) with phosgene, halogen formate or carbonic acid diester.

[Formula 1]

Wherein A represents a single bond, C ₁ -C ₅ alkylene, C ₁ -C ₅ alkylidene, C ₅ -C ₆ cycloalkylidene, -S- or -SO _2- .

Specific examples of the diphenol of the general formula (1) include 4,4'-dihydroxydiphenyl, 2,2-bis- (4-hydroxyphenyl) -propane, and 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 them, 2,2-bis- (4-hydroxyphenyl) -propane, 2,2-bis- (3,5-dichloro-4-hydroxyphenyl) -propane, 1,1-bis- (4- Bisphenols, such as hydroxyphenyl) -cyclohexane, are preferable, and 2, 2-bis- (4-hydroxyphenyl) propane also called bisphenol-A is especially preferable.

The polycarbonate resin of the present invention has a weight average molecular weight (Mw) of 10,000 to 200,000, preferably 15,000 to 80,000. If outside the range of the weight average molecular weight, there is a problem that impact resistance and workability is lowered.

The branched polycarbonate resin of the present invention may be used having a branched chain, preferably 0.052 mol% of tri- or more polyfunctional compounds, such as trivalent or more, based on the total amount of diphenols used for polymerization. It can manufacture by adding the compound which has a phenol group.

In the present invention, the polycarbonate-based resin (A) is used in the range of 20 to 80 parts by weight. Since the polycarbonate-based resin plays a role of facilitating flame retardancy, flame retardancy and mechanical strength decrease when applied to less than 20 parts by weight, and when applied to 80 parts by weight or more, it is difficult to expect improvement of scratch resistance. .

(B) methacrylate resin

The methacrylate resin (B) in the present invention is a copolymer of 50 to 100% by weight of methyl methacrylate (MMA) and 0 to 50% by weight of a monofunctional unsaturated monomer.

At this time, the methyl methacrylate (MMA) as the main component is preferably maintained at least 50% by weight of the total monomers. When the MMA is less than 50% by weight, the transparency and mechanical strength of the polymerized methacrylic resin may decrease.

The monofunctional unsaturated monomer is not particularly limited as a copolymerizable monomer. For example, methacrylates such as ethyl methacrylate, propyl methacrylate, butyl methacrylate and benzyl methacrylate, phenyl methacrylate, glycidyl methacrylate; Acrylates such as methyl acrylate, ethyl acrylate, propyl acrylate, butyl acrylate and 2-ethylhexyl acrylate; Acid anhydrides such as acrylic acid, unsaturated carboxylic acids such as methacrylic acid, maleic anhydride and the like; And monofunctional vinyl group-containing monomers such as styrene, acrylonitrile, and methacrylonitrile. These can be applied individually or in mixture of 2 or more types.

The methacrylate-based resin (B) may be polymerized by a conventionally known method, and bulk polymerization, emulsion polymerization, suspension polymerization, and the like may be applied, but are not limited thereto.

In the preparation of the methacrylate-based resin (B) may be applied to a chain transfer agent and an antioxidant in order to control the molecular weight and thermal stability, which is easily carried out by those skilled in the art to which the present invention belongs. Can be.

The methacrylate-based resin (B) used in the present invention is preferably 20 to 80 parts by weight of the base resin, it is difficult to impart scratch resistance to less than 20 parts by weight and very flame retardant when applied to more than 80 parts by weight It is lowered and it is especially difficult to achieve flame retardancy with a phosphorus flame retardant.

(C) phenolic resin

In general, acrylic resins do not have sufficient char generation during combustion, and therefore, phenol resins are used as the char forming agent in the present invention. Phenolic resin forms char in the low temperature region (300-450 ° C.), thereby effectively forming char on the surface in the early stage of combustion.

Usually, phenol resins include resol-based phenol resins and novolak-based phenol resins, and in the present invention, novolak-based phenol resins are more preferably used than resol-based phenol resins. The phenol formaldehyde novolak resin, tertiary butyl phenol formaldehyde novolak resin, paraoctyl phenol formaldehyde novolak resin, paracyano phenol formaldehyde novolak resin may be used as the novolak-based phenol resin, phenol epoxy nono Volac resins may also be preferably used. Mixtures of these may also be used. As for the said novolak-type phenol resin, about 300-10,000 are suitable for a weight average molecular weight. If it is out of the average molecular weight, there is a problem that the flame retardancy and physical property balance is lowered.

In the present invention, the phenol resin is 1 to 20 parts by weight, preferably 1 to 10 parts by weight based on 100 parts by weight of the base resin consisting of polycarbonate resin (A) and methacrylate resin (B). When applied in excess of 20 parts by weight, the mechanical properties are lowered, the weather resistance may be lowered.

(D) flame retardant

The flame retardant used in the present invention is not particularly limited and contains 1 to 50 parts by weight based on the polycarbonate and the modified methacrylate alloy resin. Phosphorus-containing flame retardants that can be applied refer to ordinary phosphorus-containing flame retardants, such as phosphorus, phosphate, phosphonate, phosphinate, phosphine oxide, and phosphate. Phosphazene and metal salts thereof may be applied.

Halogen-based compounds can also be applied as flame retardants, and halogen-based compounds are generally used. Applicable halogen compounds include decabromodiphenyl ether, decabromodiphenylethane, tetrabromobisphenol A, tetrabromobisphenol A-epoxy oligomer, octabromotrimethylphenylindan, ethylene bistetrabromophthalimide, tris ( Commercially available flame retardants such as tribromophenol) triazine and brominated polystyrene can be applied, particularly preferably halogen-based compounds which can be melted at a normal processing temperature, more specifically, having a melting point or softening point below 250 ° C. Compounds are preferred. When the halogen-based compound is applied, inorganic compounds such as antimony trioxide and antimony pentoxide may be applied depending on the use.

In the present invention, the flame retardant (C) is used in 1 to 50 parts by weight, preferably 5 to 30 parts by weight, more preferably 10 to 27 parts by weight based on 100 parts by weight of the base resin. When the flame retardant (C) is out of the range of 1 to 50 parts by weight based on 100 parts by weight of the base resin, there is a problem that the heat resistance and moldability is lowered.

(E) impact modifier

In the present invention, a graft copolymer or an olefin copolymer may be used as the impact modifier.

The graft copolymer may include styrene and alpha-methyl styrene capable of graft copolymerization after polymerizing at least one rubber monomer selected from the group consisting of diene rubber, acrylate rubber, and silicone rubber monomer; Alkyl substituted styrenes; Acrylonitrile; Methacrylonitrile; Methyl methacrylate; Maleic anhydride; It is produced by grafting a monomeric monomer selected from the group consisting of alkyl or phenyl nucleosubstituted maleimide and the like to a rubbery polymer. The content of rubber in the impact modifier is preferably 20 to 80 parts by weight. When the content is out of the content, the impact strength and the scratch resistance are deteriorated.

As the diene rubber, butadiene is typically used as a monomer, and isoprene may be applied. The acrylate rubber uses monomers such as methyl acrylate, ethyl acrylate, n-propyl acrylate, n-butyl acrylate, 2-ethylhexyl acrylate, hexyl methacrylate and 2-ethylhexyl methacrylate. . Silicone rubbers can be prepared from cyclosiloxanes, for example hexamethylcyclotrisiloxane, octamethylcyclotetrasiloxane, decamethylcyclopentasiloxane, dodecamethylcyclohexasiloxane, trimethyltriphenylcyclotrisiloxane, tetramethyltetraphenyl Cyclotetrosiloxane, octaphenylcyclotetrasiloxane, and the like. Silicone rubber can be used by selecting 1 or more types from the said cyclosiloxane. In addition, polyolefin-based rubbers such as ethylene / propylene rubber, ethylene-propylene-diene terpolymer (EPDM), and the like can be used.

The impact modifier used in the present invention can be selectively applied according to the use, it is preferable to apply 1 to 30 parts by weight based on 100 parts by weight of the base resin consisting of (A), (B). If it is out of the range of the weight part, a problem occurs that the impact strength and scratch resistance is lowered.

Surfactant, nucleating agent, coupling agent, filler, plasticizer, lubricant, antibacterial agent, release agent, thermal stabilizer, antioxidant, light stabilizer, compatibilizer, inorganic additive, colorant, Stabilizers, lubricants, antistatic agents, pigments, dyes, flame retardants and mixtures thereof may be added.

The resin composition of this invention can be manufactured by the well-known method of manufacturing 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 made into pellets.

The composition of the present invention can be used for molding a variety of products, and is particularly suitable for the production of electrical and electronic products, such as the housing of TVs and office automation equipment.

The invention can be better understood by the following examples, which are intended to illustrate the invention and are not intended to limit the scope of protection defined by the appended claims.

Example

Preparation and specifications of the base resin, flame retardant, impact modifier used in the following Examples and Comparative Examples are as follows.

(A) polycarbonate resin

Panlite L-1225 Grade of Teijin, Japan, was used as the polycarbonate resin.

(B) methacrylate resin

LG MMA's IH830 Grade was used as the polymethyl methacrylate resin.

(C) phenolic resin

Kolon Emulsified KPHF-2002 was used as the phenolic resin.

(D) Flame Retardant Phosphorus Compound (CR-741)

CR-741 (bisphenol A diphosphate) manufactured by Daihachi Chemical Co., Ltd., Japan, was used as a flame retardant phosphorus compound.

(E) Impact modifier (Methyl Methacrylate-Butadiene-Ethylacrylate Copolymer)

MRC's Metablen C223-A Grade was used as the impact modifier, and methyl methacrylate and styrene-grafted resin (MBS resin) was applied to butadiene rubber.

Examples 1-4 and Comparative Examples 1-2

The material of (A) ~ (E) was added to the content as shown in the following [Table 1] was extruded in a temperature range of 220 ~ 260 ℃ in a conventional twin screw extruder to prepare a pellet. The prepared pellets were dried at 80 ° C. for 3 hours and then injected at 8 ° C. in a molding temperature of 250 ° C. and mold temperature of 60 ° C. to prepare specimens for measuring impact strength, flame retardancy, and pencil hardness.

Comparative Example 1 was carried out in the same manner as in Examples 1 to 3, except that the phenol resin (C) was not used.

Comparative Example 2 was carried out in the same manner as in Example 4 except that the phenol resin (C) was not used.

For the specimens prepared by the examples and comparative examples shown in Table 1 below, the impact strength was measured according to ASTM D-256 standard, the fluidity was measured according to ASTM D-1238 standard, and the flame retardancy was determined according to the UL 94 V flame retardant standard. Flame retardancy was measured accordingly. In the case of measuring the pencil hardness, the pencil hardness was measured in accordance with JIS K 5401 after leaving for 48 hours at 50% of 23 ° C relative humidity for 10 * 10 cm 2 specimens. The scratch resistance is evaluated as 3B, 2B, B, HB, F, H, 2H, 3H, etc. according to the pencil hardness result. The higher the H value, the better the scratch resistance. The higher the B value, the lower the scratch property. Showed a tendency.

According to the embodiment of the present invention, it was possible to prepare a resin composition exhibiting the V0 flame retardance of the highest flame retardancy while maintaining excellent scratch resistance of pencil hardness H or more.

According to Examples 1, 2 and 3 and Comparative Example 1, by using phenolic resin, pencil hardness is maintained at the same level, especially the flame retardancy is remarkably improved, and the additional fluidity increases to facilitate molding during processing. You can see that there is. In addition, when comparing the Examples 2, 4 and Comparative Example 2, it can be seen that the flame retardancy is increased by using the phenol resin to increase the flame retardant content even if the flame retardant content is reduced.

The present invention provides a scratch-resistant flame-retardant thermoplastic resin composition not only excellent in flame retardancy, but also excellent in transparency and scratch resistance, and improved flame retardancy by adding a phenol novolak resin, and provides a plastic molded article manufactured using the composition. It has the effect of the invention.

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 (9)

(A) 20 to 80 parts by weight of a polycarbonate resin; And (B) 20 to 80 parts by weight of methacrylate resin; Based on 100 parts by weight of the base resin consisting of, (C) 1 to 20 parts by weight of the phenol resin; And (D) 1 to 50 parts by weight of a flame retardant; Scratch-resistant flame-retardant thermoplastic resin composition comprising a. The scratch-resistant flame retardant thermoplastic resin composition according to claim 1, wherein the methacrylate-based resin (B) is a copolymer of 50 to 100% by weight of methyl methacrylate and 0 to 50% by weight of a monofunctional unsaturated monomer. The scratch-resistant flame retardant thermoplastic resin composition according to claim 1, wherein the phenol resin (C) is one or a mixture thereof selected from the group consisting of phenol novolak resins and phenol epoxy novolak resins. The method of claim 1, wherein the flame retardant (D) is a phosphate (Phosphate), phosphonate (Phosphonate), phosphinate (Phosphinate), phosphine oxide (Phosphine Oxide), phosphazene (Phosphazene) and metal salts thereof Scratch-resistant flame-retardant thermoplastic resin composition comprising one or two or more flame retardants selected from. The scratch-resistant flame retardant thermoplastic resin composition according to claim 1, further comprising 1 to 30 parts by weight of (E) impact modifier, based on 100 parts by weight of the base resin. The method of claim 5, wherein the impact modifier (E) is a styrene, alpha-methyl graft copolymerizable after polymerizing at least one rubber monomer selected from the group consisting of diene rubber, acrylate rubber, and silicone rubber monomer Styrene; Alkyl substituted styrenes; Acrylonitrile; Methacrylonitrile; Methyl methacrylate; Maleic anhydride; Scratch-resistant flame-retardant thermoplastic resin composition, characterized in that the rubber polymer is produced by grafting at least one monomer selected from the group consisting of alkyl or phenyl nucleosubstituted maleimide. The method of claim 1, wherein the flame retardant thermoplastic resin composition is a surfactant, nucleating agent, coupling agent, filler, plasticizer, lubricant, antibacterial agent, mold release agent, thermal stabilizer, antioxidant, light stabilizer, compatibilizer, inorganic additive, colorant, stabilizer, lubricant The scratch-resistant flame retardant thermoplastic resin composition further comprises an additive selected from the group consisting of antistatic agents, pigments, dyes, flame retardants and mixtures thereof. The scratch-resistant flame retardant thermoplastic resin composition of claim 3, wherein the phenol novolak resin has a weight average molecular weight of 300 to 10,000. A molded article extruded from the scratch-resistant flame retardant thermoplastic resin composition according to any one of claims 1 to 8.