KR100804547B1 - Composition of pmma with glossy, anti-static, abrasion resistant, impact resistant - Google Patents

Abstract

A poly(methyl methacrylate) (PMMA)-based resin composition, and an external material using the composition are provided to reduce brittleness and to improve gloss, scratch resistance and antistatic property. A PMMA-based resin composition comprises 100 parts by weight of a PMMA-based resin; 5-40 parts by weight of an impact modifier which comprises a resin particle having a core or a multilayered structure of core and middle layer obtained by polymerizing butadiene, at least one comonomer selected from methyl methacrylate, methyl acrylate, ethyl (meth)acrylate, butyl (meth)acrylate and styrene, and at least one crosslinking agent selected from divinyl benzene, ethylene glycol dimethacrylate, diethylene glycol dimethacrylate and diethylene glycol dimethacrylate; 0.5-5 parts by weight of an antistatic agent which comprises at least one selected from an anionic surfactant and a nonionic surfactant; and 0.02-10 parts by weight of a synthetic lubricating oil.

Description

Polymethyl methacrylate resin composition excellent in surface gloss, antistatic property, abrasion resistance and impact resistance {Composition of PMMA with glossy, anti-static, abrasion resistant, impact resistant}

The present invention relates to a polymethyl methacrylate (hereinafter referred to as PMMA) resin composition having excellent gloss, scratch resistance, and brittleness, which is applicable to display transparent materials and external materials for home appliances, and is provided with antistatic properties.

Polymethyl methacrylate (PMMA) resin, a polymer of methyl methacrylate monomer, is a transparent resin with excellent light transmittance, and is widely applied as a display transparent material such as light guide plate, diffuser plate, and projection TV screen of various monitors. It is excellent and is used as exterior material of various electronic products.

PMMA resin, like general plastic resin, is electrically insulative, charge is easy to charge, and there is a possibility of aesthetic problems caused by the adhesion of dust or foreign substances and the possibility of failure accompanied by static electricity. Was being asked. As a method of imparting the antistatic property of the resin, in general, the external coating method is usually subjected to an application process in which an antistatic agent is attached to the surface layer by spray coating or dipping. Although the effect can be seen as a relatively small amount of antistatic agent through coating, there is a disadvantage that it is difficult to sustain the antistatic effect because streaks are easily formed after molding and are easily lost by washing or friction.

A method of containing graphite fibers or carbon black as a method of adding an antistatic agent to a resin before molding in a manner that does not go through such a surface coating step has been proposed. However, when carbon black or the like is mixed, the resin is colored, and there is a problem in that it cannot be used when coloring the application or a light color requiring transparency. In addition, it is proposed to provide an antistatic performance by mixing a chlorine salt of phosphonium salt or ammonium salt into the resin as an antistatic agent, but in such a method, free chlorine ions are generated to corrode expensive molds used for molding the resin. There is a problem.

In order to solve the above problems, the present invention does not significantly affect the appearance of the polymethyl methacrylate (PMMA) resin by using anionic surfactants or nonionic surfactants alone or in combination, and has excellent antistatic properties. The purpose is to provide a PMMA resin composition.

In addition, in the case of exterior materials such as large electronic products, synthetic lubricants such as silicone oil may be applied to the surface of the product after molding to avoid problems such as scratching of the surface during handling such as transport after injection molding. By adding synthetic lubricating oil to the resin before molding, it can impart lubricating properties to the surface of the product and by adding appropriate synthetic lubricating oil to improve the brittleness of the product. It was found that not only can achieve space and cost reduction but also permanently excellent surface properties through the shortening of the secondary production process of surface coating through the method, and the PMMA resin composition can be used for the appearance of various home appliances. To provide.

That is, the present invention has a fluidity which can be molded into a desired shape by processing such as extrusion or injection, has brittleness (impact strength) suitable for assembly, etc., and provides excellent antistatic property without degrading the inherent glossiness and wear resistance of PMMA. It is to provide a resin composition that can be.

An object of the present invention is a polymethyl methacrylate-based resin having excellent appearance characteristics of PMMA, having abrasion resistance that can be used as an exterior material such as home appliances, and sufficient brittleness not to be destroyed in assembly, etc., and having excellent antistatic properties. To provide a composition.

As a result of trying to achieve the above object, the present inventors have a good antistatic properties and lubrication properties without the external coating process by blending a specific type of antistatic agent and synthetic lubricant to PMMA resin, and a specific type of impact modifier The present invention was completed by discovering that a resin composition having sufficient brittleness, and particularly excellent gloss, can be produced even after coloring.

In order to achieve the above object, the present inventors (A) butadiene, methyl methacrylate and methyl acrylate, ethyl (meth) acrylate, butyl (meth) acrylate, styrene based on 100 parts by weight of PMMA resin Polymerizing any one or more comonomers and at least one crosslinking agent in divinylbenzene, ethylene glycol dimethacrylate, diethylene glycol dimethacrylate, diethylene glycol dimethacrylate to form a core or an interlayer with the core 5 to 40 parts by weight of impact modifier consisting of resin particles having a multilayer structure of two or more layers (C) 0.5 to 5 parts by weight of an antistatic agent consisting of a single or a mixture selected from anionic surfactants and nonionic surfactants (D) By mixing 0.02 ~ 10 parts by weight of lubricating oil, PMMA resin with high brittleness, antistatic and abrasion resistance, excellent gloss after coloring and beautiful color The composition was prepared.

In addition, the present invention by using at least 1 to 3 parts by weight of at least one component selected from glycerin, glyceryl monostearate, polyethylene glycol to the composition is excellent in scratch resistance, antistatic properties are improved The effect could be achieved.

The present invention uses the above-mentioned specific components in a specific content range, so that the surface gloss of 90% or more, the transmittance of 85% or more, the pencil hardness of HB or more, the Izod strength of 8kJ / m2 or more, the flowability and the antistatic property of 2.5g / 10min or more are excellent. It was found that the effect was completed the present invention.

In particular, the composition according to the present invention is excellent in fluidity and impact strength, and can be processed afterwards, and by using a specific antistatic agent so as not to lose the gloss, it is not only excellent in gloss and scratch resistance, but also excellent in antistatic property. Or it can be applied to the exterior material of various electronic products.

(A) PMMA resin used in the present invention is a methyl methacrylate homopolymer or copolymer, the copolymer is methyl methacrylate and methyl acrylate, ethyl (meth) acrylate, butyl (meth) acrylate, It is made of a resin characterized in that the copolymer is polymerized with at least one component selected from styrene.

The composition ratio of the comonomers used in the present invention is not particularly limited as long as methyl methacrylate (MMA) is used as the main component, but preferably 50 to 99% by weight of methyl methacrylate and 1 to 50% by weight of comonomers. It is good to use it in the ratio of superposition | polymerization. More preferably, the use of 65 to 97% by weight of MMA and 35 to 3% by weight of comonomer does not lose wear resistance and transparency.

Preferably the weight average molecular weight of said (A) PMMA type resin used for this invention is 60,000-150,000, More preferably, it is 70,000-130,000. When the molecular weight of the resin (A) is 150,000 or more, the impact strength and the effect of dispersing the composition are improved, but the fluidity of the composition is lowered, and the post-processing property is lowered. It is not good due to lack of impact strength and dispersibility.

The (B) impact modifier used in the present invention polymerizes at least one comonomer selected from butadiene, methyl methacrylate and methyl acrylate, ethyl (meth) acrylate, butyl (meth) acrylate and styrene, or Resin particles having a multilayer structure of two or more layers forming a core and an intermediate layer are used.

Specifically, divinylbenzene, ethylene glycol dimethacrylate as a crosslinking agent in the polymerization of at least one comonomer selected from butadiene, methyl methacrylate and methyl acrylate, ethyl (meth) acrylate, butyl (meth) acrylate and styrene. The resin particle which has a multilayered structure which makes the core material the rubber polymer which uses 1 or more types of diethylene glycol dimethacrylate and diethylene glycol dimethacrylate as the core material, The average particle diameter is 0.1-0.3 micrometer. If the rubber particles are too small, the effect of improving the impact strength is insignificant, and if the rubber particles are too large, scratch resistance, gloss and permeability decrease due to the rubber particles located on the surface.

The (B) impact modifier is a three-layer or two-layer particles, the inner or inner and middle layers of the rubber layer as described above to express excellent impact strength, the outermost layer is grafted with methyl methacrylate This improves the compatibility with PMMA and improves dispersion. For example, UMG's MUX60 was used as an acrylic impact modifier. The average particle diameter of the particles was 0.2 μm. The content is preferably 5 to 40 parts by weight, and when the content exceeds 40 parts by weight, the hardness is low, scratch resistance and gloss are reduced.

As the antistatic agent (C) used in the present invention, an anionic surfactant or a mixture of one or more selected from nonionic surfactants is used.

For example, as the anionic antistatic agent, sulfonates, sulfates, phosphites, dithiocarbonates, and the like are used. Sulfonate-based products include TCI's MOA, American Hoeschast's Hostastat HS1, and phosphite-based GAafa Gafac series. In particular, sodium alkylsulfonates among the anionic antistatic agents show excellent antistatic effect not only for PMMA resins but also for styrene resins and PVC, and are excellent in terms of practical use.

As the nonionic antistatic agent, an amide compound or an amine compound is used, and N, N-bis (2-hydroxyethyl) alkyl amine, N-2-hydroxyethyl-N- 2-hydroxy alkylamine, polyoxyethylene alkylamine, etc. are mentioned.

The antistatic agent is preferably used in 0.5 to 5 parts by weight. If the amount is less than 0.5 parts by weight, the surface resistivity of 10 ¹² Ω, which is generally considered necessary for antistatic, is not achieved, and if it is more than 5 parts by weight, mechanical or optical properties are impaired. In this tendency, the blending ratio of the antistatic agent is preferably 0.5 to 3.5 parts by weight.

In the present invention, when the antistatic agent and a low concentration of glycerin (Glycerine), glyceryl monostearate (Glyceryl monostearate) or polyethylene glycol (1-3 parts by weight) are used together and the effect is increased. If the amount is less than 1 part by weight, the effect is insignificant, and if it is more than 3 parts by weight, it may cause problems such as gas generation during processing, which may cause problems with the color or gloss of the surface of the product. Further, in order to further improve the antistatic performance of the antistatic agent as described above, it is also possible to further add a carbon filler such as carbon black or carbon nanotubes as the conductive material.

The synthetic lubricant (D) used in the present invention is used to improve the lubricity of the surface after molding, and silicone oil, synthetic hydrocarbon oil, fluorine oil, and the like can be used. In particular, when an appropriate silicone oil is applied, the impact strength of the resin is increased to improve the brittleness of the product.

Silicone oil used in the present invention is a polymer of dimethyl siloxane (dimethyl siloxane) or a methyl group of dimethyl siloxane or a portion thereof is one or more aliphatic or aromatic, such as hydrogen, phenyl group, halogenated phenyl group, halogenated alkyl group, fluoro ester group Dimethyl siloxane derivatives in substituted form. The viscosity of the silicone oil may be 5 ~ 50,000 cSt, a viscosity range of 50 ~ 5,000 cSt is preferred. In addition, in a molded article that requires transparency, a desired surface property can be exhibited without selecting the silicone oil having a refractive index range of 1.45 to 1.52 without impairing the transparency of the resin. The content of the synthetic lubricating oil is preferably used 0.02 ~ 10 parts by weight.

In the present invention, the method of mixing the resin composition may be mixed with a mixer such as a well-known Henschel mixer, a ball mill, a tumbler mixer, and the like, followed by melt mixing using a melt extruder or the like. The blending temperature of the resin composition is suitably between 180 and 250 ° C. The order of fusion is not important. For example, a master batch method may be used in which pellets obtained by blending an impact modifier or an antistatic agent in a high concentration in advance with a base resin are mixed immediately before molding.

The resin composition according to the present invention may comprise common thermoplastic additives such as fillers, reinforcing agents, colorants, lubricants, stabilizers, antioxidants, heat resistant and ultraviolet stabilizers and other compound components.

Based on the above description, those skilled in the art will be able to easily understand the essential features of the present invention, and changes and modifications suitable for various uses, conditions, and specific examples can be made without departing from the spirit and scope of the present invention. Can be applied.

The composition according to the present invention can be applied as an exterior material, and in particular, it can be applied to display transparent materials such as light guide plates, diffusion plates, and projection TV screens of various monitors, or exterior materials of various electronic products having excellent wear resistance and appearance. It can be seen that.

Hereinafter, the PMMA resin composition according to the present invention will be described by examples which do not limit the scope of the present invention.

Brittleness was measured for Izod impact strength according to ASTM D256. If the impact strength is less than 3kg · cm / cm, there is a risk of problems such as cracking during assembly.

Scratch resistance was measured by pencil hardness according to ASTM D3363. To be used for exterior, pencil hardness more than HB is required.

Surface resistance was measured using Ando Electric VMG-1000 according to ASTM D257.

Workability was measured by the flow (Melt Flow Index, MI) according to ASTM D1238. If Melt Flow Index is 1 or more, post-processing such as injection and extrusion is possible.

The external appearance of the surface was measured at 45 degree glossiness using a glossmeter according to ASTM D523. If the glossiness is 90% or more, the appearance is good.

[Examples and Comparative Examples]

PMMA resin composition was prepared with the resins, additive components, and composition ratio contents shown in Table 1, and the results are shown in Table 2.

First, the resin component having the physical properties shown in Table 1 was mixed, and the resin composition was introduced from the hopper while stirring the screw at 200 rpm using a 32 pi twin screw extruder (L / D: 30) (manufactured by SM Platec). It was. The hopper was cooled by circulating cooling water. The screw was melt kneaded by maintaining the front end (1-2 zones) at 180 ° C and the rear end (3-7 zones) at 210 ° C. The temperature of the extrusion die was kept at 235 ° C and extruded at 20kg / hr. Cooled and cut to pellet.

The sample injection molding machine (LG wires, 100 ton) was used with a nozzle temperature of 223 ℃ 1 primary injection pressure of 100 kg / cm ^{2, 2} primary injection pressure of 60 kg / cm ^2, the back pressure from 10kg to evaluate basic physical properties test / cm ² and the injection time was 15 seconds and the injection screw was prepared at an injection screw at 100 rpm. The extrudate was measured after 48 hours stay at room temperature for physical properties evaluation. The results are shown in Table 2.

Table 1. Composition Components of Examples (Unit: Weight part)

(1) PMMA is a product of LG MMA Co., Ltd. using a polymer composed of 95 parts by weight of methyl methacrylate and 5 parts by weight of methyl acrylate. (Weight average molecular weight 120,000)

(2) UMG's MUX60 used (composed of butadiene, butyl acrylate, methyl methacrylate)

(3) Use of LG Chemical's SIM100. (Composed of polydimethylsiloxane, butyl acrylate, styrene, acrylonitrile)

(4) TCI sodium dodecylbenzenesulfonic acid use.

(5) Use of Ilshinwell's glycerin monostearate.

(6) Carbon black EC 600JD from KetjenBlack International.

(7) KF-96-50 from Shinetsu Chemical Industries, Ltd. (Kinetic viscosity 50cSt, refractive index 1.402)

(8) KF-54 from Shinetsu Chemical Industries, Ltd. (Kinetic viscosity 400cSt, refractive index 1.505)

Table 2. Property comparison of PMMA moldings

As shown in the table, the resin composition according to the present invention can be seen that the flow index is suitable for post-processing, brittleness, pencil hardness is suitable, the volume resistance value of 1x10 ¹² has an antistatic effect.

In Example 2, when the content of silicone oil is increased, the Izod strength is increased.

In Example 3, when the glycerin monostearate was not used, it was found that the antistatic property was decreased and the surface lubricity was further reduced, but the results satisfied the brittleness, the pencil hardness, and the antistatic property as the object of the present invention. .

When the type of silicone oil in Example 4 using KF-54 (Kinetic viscosity 400cSt, refractive index 1.505) of Shinetsu Chemical Industries, it was found that the transmittance was higher than that of Example 2.

Therefore, it can be seen that the resin composition of the present invention can be applied to display transparent materials such as light guide plates, diffusion plates, and projection TV screens of various monitors, or exterior materials of various electronic products having excellent wear resistance and appearance.

However, when the content of the impact modifier is outside the scope of the present invention as in Comparative Example 1, it was found that the fluidity is not suitable for molding, and the scratch resistance is reduced, and the surfactant and the glycerin monostearate are not used as an antistatic agent. When the carbon black was added, the surface resistivity was obtained in the same physical properties as the present invention, but the transmittance and gloss were decreased, and thus the surface resistance was not satisfactory. In addition, as in Comparative Example 2, the use of other types of impact modifiers did not satisfy the Izod strength and did not have fluidity suitable for processing. In addition, since the content of the antistatic agent is excessively used, the antistatic effect may be increased, but a satisfactory appearance may not be obtained due to a decrease in transmittance and gloss due to excessive antistatic agent.

By using the resin composition of the present invention, the fluidity and the impact strength are balanced to the desired physical properties to enable post-processing such as injection, extrusion and assembly, and have antistatic properties and improve gloss and scratch resistance without being painted. By omitting the coating step, it is possible to obtain an exterior material having a good appearance at low cost. In addition, in the case of the composition according to the present invention, it is possible to manufacture moldings having excellent processability, impact resistance, abrasion resistance, and antistatic property, and thus can be used as an exterior material, and a new PMMA system that can be used as it is by omitting a coating process. The resin composition could be provided.

Claims (10)

 (A) One or more comonomers and divinyl selected from (B) butadiene, methyl methacrylate and methyl acrylate, ethyl (meth) acrylate, butyl (meth) acrylate and styrene based on 100 parts by weight of PMMA resin A resin particle having a multilayer structure of two or more layers which polymerizes one or more crosslinking agents in benzene, ethylene glycol dimethacrylate, diethylene glycol dimethacrylate and diethylene glycol dimethacrylate to form a core or an intermediate layer with the core. 5 to 40 parts by weight of the impact modifier (C) 0.5 to 5 parts by weight of an antistatic agent consisting of a single or a mixture selected from anionic surfactants and nonionic surfactants (D) 0.02 to 10 parts by weight of synthetic lubricant oil PMMA resin composition having excellent surface gloss, antistatic property, abrasion resistance and impact resistance. The method of claim 1, PMMA-based excellent surface gloss, antistatic, wear resistance and impact resistance, characterized in that the composition is used by adding at least 0.5 to 3 parts by weight of at least one component selected from glycerin, glyceryl monostearate, polyethylene glycol Resin composition. The method of claim 1, The (A) PMMA resin is a methyl methacrylate homopolymer or copolymer, wherein the copolymer is selected from methyl methacrylate and methyl acrylate, ethyl (meth) acrylate, butyl (meth) acrylate, and styrene. PMMA-based resin composition excellent in surface gloss, antistatic properties, wear resistance and impact resistance, characterized in that the copolymer of any one or more comonomers. The method of claim 3, wherein The copolymer is a PMMA resin composition excellent in surface gloss, antistatic properties, wear resistance and impact resistance, characterized in that the polymerization is used in a ratio of 50 to 99% by weight of methyl methacrylate and 1 to 50% by weight of comonomer. The method of claim 1, The impact modifier PMMA resin composition excellent in surface gloss, antistatic, wear resistance and impact resistance, characterized in that the outermost layer is grafted with methyl methacrylate. The method of claim 5, The impact modifier is a PMMA resin composition excellent in surface gloss, antistatic properties, wear resistance and impact resistance, characterized in that the average particle diameter of 0.1 ~ 0.3㎛. The method of claim 1, The synthetic lubricating oil is a PMMA resin composition having excellent surface gloss, antistatic property, wear resistance and impact resistance, characterized in that at least one selected from silicon oil, synthetic hydrocarbon oil, and fluorine oil. The method of claim 7, wherein The synthetic lubricating oil has excellent surface gloss, antistatic property, wear resistance and impact resistance, characterized in that it has a viscosity range of 50 ~ 5,000cSt PMMA resin composition. The method according to any one of claims 1 to 8, The PMMA resin composition has a surface gloss of 90 to 98%, a transmittance of 85 to 92%, a pencil hardness of HB to H, an Izod strength of 8 to 9.2 kJ / m 2, and a flowability of 2.5 to 3 g / 10 min. PMMA resin composition having excellent surface gloss, antistatic property, wear resistance and impact resistance. A packaging material using the PMMA resin composition according to any one of claims 1 to 8.