KR101666701B1 - Acrylic Rubber Modified Graft Copolymer Having Excellent Impact-resistance and Colorability, and Method for Preparing Same - Google Patents

Abstract

The acrylic rubber-modified graft copolymer according to the present invention comprises (A) a first core layer obtained by polymerizing an alkyl acrylate monomer, a second core layer obtained by copolymerizing an alkyl acrylate monomer and an aromatic vinyl monomer, and a second core layer obtained by copolymerizing an alkyl acrylate monomer and an aromatic A core layer (A) comprising a third core layer copolymerized with a vinyl monomer; And (B) an aromatic vinyl monomer and an unsaturated nitrile monomer; Wherein the cross-linking density of the core (A) is increased from the first core layer to the third core layer, and the average particle diameter of the core (A) is 50 To 500 nm, and is excellent in impact resistance and coloring property.

Description

TECHNICAL FIELD [0001] The present invention relates to an acrylic rubber-modified graft copolymer having excellent impact resistance and coloring property, and a process for producing the same. BACKGROUND ART [0002]

The present invention relates to an acrylic rubber-modified graft copolymer. More specifically, the present invention relates to an acrylic rubber-modified graft copolymer excellent in impact resistance and colorability.

Generally, acrylonitrile-butadiene-styrene resin (hereinafter, referred to as 'ABS resin') has excellent impact resistance, mechanical strength, surface characteristics and processability and is widely used in electric / electronic products, automobile parts and general merchandise.

However, since the ABS resin contains a chemically unstable double bond in the rubber component in the resin, the rubber component can be easily aged by ultraviolet rays, so that the weather resistance and the light resistance are poor. In addition, when left outdoors for a long time, it is not suitable for outdoor use exposed to sunlight due to large discoloration and deterioration of physical properties over time.

Therefore, in order to compensate for this, a method of post-processing such as painting or plating on an ABS resin molded article, or adding a large amount of a UV stabilizer during extrusion processing of an ABS resin is used. However, the former method has a disadvantage in that the process is complicated and the defect rate is high, and the latter method has a disadvantage in that the production cost is not increased and satisfactory long-term weatherability is not obtained.

In order to overcome the limitation of the use of such an ABS resin, various resins known to have excellent weather resistance are used instead of ABS resin. A double acrylate-styrene-acrylonitrile resin (hereinafter referred to as ASA resin) It is the most widely used.

The ASA resin generally comprises an acrylic graft copolymer obtained by graft-polymerizing an unsaturated nitrile compound and an aromatic vinyl compound onto an acrylic rubber-like polymer, and an unsaturated nitrile-aromatic vinyl copolymer obtained by copolymerizing an unsaturated nitrile compound and an aromatic vinyl compound, . At this time, by adjusting the physical properties and the content of the acrylic graft copolymer and the unsaturated nitrile-aromatic vinyl compound copolymer to be used, and optionally adding a reinforcing agent having a specific role, a resin having desired properties can be obtained. Since the ASA resin is excellent in weatherability, light resistance, chemical resistance and heat resistance, it is suitable for use in exterior parts for outdoor use such as outdoor electric / electronic products, automobile exterior parts, and construction materials.

However, the ASA resin has a disadvantage in that the impact resistance is poor. To solve this problem, a method of increasing the diameter of the rubbery polymer or lowering the gel content of the rubbery polymer has been used. However, these methods are not only difficult to control the physical properties of the graft copolymer but also deteriorate the physical properties of the resin such as the gloss. In order to improve the impact resistance, there is a method of improving physical properties such as impact resistance and gloss using acrylic rubber polymers having different average particle diameters, but it is difficult to attain desired physical properties.

On the other hand, since heat resistance is indispensable for outdoor use, conventionally, a copolymer resin of an unsaturated nitrile compound and an a-methylstyrene compound is used in order to improve the heat resistance of an ASA resin which is a weather resistant resin. However, the copolymer of the unsaturated nitrile compound and the a-methylstyrene compound used for obtaining the heat resistant property has excellent heat resistance characteristics, but the amount of gas generated is large, which causes the injection stability to deteriorate and the appearance property to deteriorate. The yellow color was poor in colorability.

Korean Patent Publication No. 2007-0117315 discloses a rubbery polymer and a double structure of a double structure core layer comprising an inner core layer made of an alkyl acrylate-aromatic vinyl copolymer and an outer core layer made of an alkyl acrylate polymer. Discloses an ASA graft copolymer comprising a shell formed by grafting an aromatic vinyl compound-unsaturated nitrile compound copolymer. However, such an ASA graft copolymer does not have sufficiently satisfactory impact resistance and fluidity.

Accordingly, the present inventors have developed an acrylic rubber-modified graft copolymer excellent in impact resistance and coloring property by controlling the average particle size of the core layer and the content of the aromatic vinyl monomer in the acrylic rubber-modified graft copolymer having a core-shell structure will be.

An object of the present invention is to provide an acrylic rubber-modified graft copolymer excellent in impact resistance.

Another object of the present invention is to provide an acrylic rubber-modified graft copolymer excellent in coloring property.

Another object of the present invention is to provide an acrylic rubber-modified graft copolymer excellent in fluidity.

It is still another object of the present invention to provide an acrylic rubber-modified graft copolymer excellent in heat resistance.

Another object of the present invention is to provide a process for producing an acrylic rubber-modified graft copolymer excellent in impact resistance and coloring property.

These and other objects of the invention are all achievable by the invention which is described below.

The acrylic rubber-modified graft copolymer according to the present invention comprises (A) a first core layer obtained by polymerizing an alkyl acrylate monomer, a second core layer obtained by copolymerizing an alkyl acrylate monomer and an aromatic vinyl monomer, and a second core layer obtained by copolymerizing an alkyl acrylate monomer and an aromatic A core comprising a third core layer copolymerized with a vinyl monomer; And (B) a graft copolymerized monomer mixture comprising an aromatic vinyl monomer and an unsaturated nitrile monomer or a monomer mixture comprising an alkyl (meth) acrylate monomer, wherein the core (A) The cross-link density increases toward the three-core layer, and the average particle diameter of the core (A) may be 50 to 500 nm.

The acrylic rubber-modified graft copolymer of the present invention may comprise 30 to 80% by weight of the core (A) and 20 to 70% by weight of the shell (B).

The core (A) of the present invention may comprise 10 to 50% by weight of the first core layer, 25 to 45% by weight of the second core layer and 25 to 45% by weight of the third core layer.

The second core layer of the present invention comprises 80 to 99% by weight of an alkyl acrylate monomer and 1 to 20% by weight of an aromatic vinyl monomer, and the third core layer comprises 80 to 99% by weight of an alkyl acrylate monomer and 1 to 20% by weight of an aromatic vinyl monomer 20% by weight.

The first core layer, the second core layer and the third core layer of the present invention may further comprise a cross-linking agent, an emulsifier, an electrolyte or a mixture thereof.

The first core layer of the present invention further comprises 0 to 0.05 parts by weight of a crosslinking agent based on 100 parts by weight of the alkyl acrylate monomer contained in the core (A), and the second core layer comprises the alkyl acrylate monomer The third core layer may further comprise 0.01 to 1.5 parts by weight of a crosslinking agent based on 100 parts by weight of the alkyl acrylate monomer contained in the core (A).

The emulsifier used in the first core layer, the second core layer and the third core layer of the present invention is a sulfonic emulsifier or a mixture thereof. The first core layer further comprises 0.01 to 1.0 part by weight of an emulsifier based on 100 parts by weight of the alkyl acrylate monomer contained in the core (A), and the second core layer comprises 100 parts by weight of the alkyl acrylate monomer contained in the core (A) And the third core layer may further comprise 0 to 1.0 part by weight of an emulsifier based on 100 parts by weight of the alkyl acrylate monomer contained in the core (A).

The first core layer, the second core layer and the third core layer of the present invention may further include an electrolyte. The first core layer further comprises 0.01 to 1.0 part by weight of the electrolyte relative to 100 parts by weight of the alkyl acrylate monomer contained in the core (A), and the second core layer comprises 100 parts by weight of the alkyl acrylate monomer contained in the core (A) , And the third core layer may further comprise 0 to 1.0 part by weight of the electrolyte with respect to 100 parts by weight of the alkyl acrylate monomer contained in the core (A).

The core (A) of the present invention has a weight average molecular weight of 1,000,000 to 10,000,000 g / mol.

The alkyl acrylate monomer of the present invention may be an alkyl acrylate monomer having 2 to 20 carbon atoms.

The aromatic vinyl monomer of the present invention may be styrene,? -Ethylstyrene,? -Methylstyrene, p-methylstyrene, o-t-butylstyrene, bromostyrene, chlorostyrene, trichlorostyrene or a mixture thereof.

The unsaturated nitrile monomers of the present invention may be acrylonitrile, methacrylonitrile, fumaronitrile, or mixtures thereof.

The alkyl (meth) acrylate monomer of the present invention may be an alkyl (meth) acrylate monomer having 2 to 20 carbon atoms.

The shell (B) of the present invention comprises 20 to 90% by weight of an aromatic vinyl monomer, and 10 to 80% by weight of an unsaturated nitrile monomer; Or from 50 to 100% by weight of an alkyl (meth) acrylate monomer and from 0 to 50% by weight of an alkyl (meth) acrylate monomer different from the alkyl (meth) acrylate monomer.

The polycarbonate resin composition according to the present invention may include the acrylic rubber-modified graft copolymer and polycarbonate resin.

The molded article according to the present invention can be produced from the polycarbonate resin composition.

The molded article of the present invention had an Izod impact strength of 40 to 47 kgf · cm / cm measured at a temperature of 23 ° C. and a thickness of 1/4 "in accordance with ASTM D256, a temperature of 23 ° C. and a temperature of 23 ° C. in accordance with ASTM D256, The Izod impact strength measured at a thickness of 8 "may be 57 to 70 kgf · cm / cm.

The molded article of the present invention may have a melt flow index (MI) of 19 to 25 g / 10 min measured at a temperature of 200 캜 and a load of 5 kg according to ASTM D1238.

The molded article of the present invention may have a Vicat softening point measured according to ISO 306 / B50 of 94 to 97 占 폚.

When the molded article of the present invention is black, it has an L value of 27 to 30, an a value of -0.1 to 0.2 as measured by the International Lighting Committee (CIE) Lab using a CM-3500d spectrophotometer from Minolta Co., , and the b value may be -1.3 to -0.1.

The method for producing an acrylic rubber-modified graft copolymer having a core-shell structure according to the present invention comprises the steps of: (1) polymerizing an alkyl acrylate monomer to form a first core layer; (2) (3) copolymerizing an alkyl acrylate monomer and an aromatic vinyl monomer with the second core layer to form a third core layer, wherein the core layer is formed by copolymerizing a monomer and an aromatic vinyl monomer; and A); And graft-copolymerizing an aromatic vinyl monomer and an unsaturated nitrile monomer to the core or graft-copolymerizing an alkyl (meth) acrylate monomer to the core to form a shell (B).

Hereinafter, the present invention will be described in detail.

The acrylic rubber-modified graft copolymer according to the present invention has an effect of providing an acrylic rubber-modified graft copolymer excellent in impact resistance, coloring property, fluidity and heat resistance and a process for producing the same.

The present invention relates to an acrylic rubber-modified graft copolymer, and more particularly to an acrylic rubber-modified graft copolymer excellent in impact resistance and colorability.

Acrylic Rubber Modification Graft  Copolymer

The acrylic rubber-modified graft copolymer is a graft-polymerized mixture of an acrylic rubber polymer and a monomer mixture composed of an aromatic vinyl compound and an unsaturated nitrile compound, and is well known to those skilled in the art.

The present invention relates to a method of forming a first core layer, a second core layer, and a third core layer by using a crosslinking agent, an emulsifier and an electrolyte stepwise in an alkyl acrylate monomer so as to obtain excellent impact resistance and colorability, , The second core layer, and the third core layer were gradually increased in the order of 50 to 500 nm, and the core was formed. Thereafter, the acrylic rubber-modified graft copolymer of the present invention was prepared by graft-polymerizing an aromatic vinyl monomer and an unsaturated nitrile monomer to the core or graft-polymerizing an alkyl methacrylate monomer to form a shell.

The acrylic rubber-modified graft copolymer according to the present invention comprises (A) a first core layer obtained by polymerizing an alkyl acrylate monomer, a second core layer obtained by copolymerizing an alkyl acrylate monomer and a styrene monomer, and an alkyl acrylate monomer and an aromatic vinyl A core comprising a third core layer obtained by copolymerizing monomers; and (B) an aromatic vinyl monomer and an unsaturated nitrile monomer; Wherein the cross-linking density of the core (A) increases from the first core layer to the third core layer, and the core (A) has an average particle diameter of 50 to 500 nm Is a core-shell structure.

The acrylic rubber-modified graft copolymer is composed of 30 to 80% by weight of core (A) and 20 to 70% by weight of shell (B).

Hereinafter, the acrylic rubber-modified graft copolymer of the present invention will be described in more detail.

(A) Core

The core (A) of the present invention comprises a polymer polymerized with an alkyl acrylate monomer and has a structure of a triple core.

The core (A) comprises 10 to 50% by weight of the first core layer, 25 to 45% by weight of the second core layer and 25 to 45% by weight of the third core layer. When the content ranges of the first core layer to the third core layer are within the above ranges, the acrylic rubber-modified graft copolymer is excellent in impact resistance.

The first core layer is formed by polymerizing an alkyl acrylate monomer as an acrylic rubbery polymer. The second core layer is formed by copolymerizing an alkyl acrylate monomer and an aromatic vinyl monomer together with a crosslinking agent and an emulsifier in the first core layer and the third core layer is formed by copolymerizing an alkyl acrylate monomer and an aromatic And a vinyl monomer. The first core layer does not contain an aromatic vinyl monomer, thereby lowering the glass transition temperature of the core (A) and improving the impact reinforcing effect of the acrylic rubber-modified graft copolymer. In addition, by containing the aromatic vinyl monomer in the third core layer, the core (A) can be made more spherical and the impact reinforcing effect of the acrylic rubber-modified graft copolymer can be improved.

The second core layer comprises 80 to 99% by weight of an alkyl acrylate monomer and 1 to 20% by weight of an aromatic vinyl monomer and the third core layer comprises 80 to 99% by weight of an alkyl acrylate monomer and 1 to 20% by weight of an aromatic vinyl monomer, Lt; / RTI > The present invention can improve the refractive index by increasing the content of the aromatic vinyl monomer component in the core (A).

The alkyl acrylate monomers include alkyl acrylates having 2 to 20 carbon atoms such as methyl acrylate, ethyl acrylate, propyl acrylate, isopropyl acrylate, t-butyl acrylate, n-butyl acrylate, n-octyl acrylate, Acrylate monomers such as methyl acrylate, ethyl acrylate, ethyl acrylate, ethyl acrylate, ethyl acrylate and ethylhexyl acrylate; and monomers such as methyl methacrylate, ethyl methacrylate, propyl methacrylate, isopropyl methacrylate, Methacrylate, and 2-ethylhexyl methacrylate. These monomers may be used singly or in combination. Of these, n-butyl acrylate or n-butyl methacrylate can be preferably used.

The aromatic vinyl monomers include side chain alkyl substituted styrenes such as styrene, alpha -ethylstyrene and alpha -methylstyrene, alkyl substituted styrenes such as p-methylstyrene and ot-butylstyrene, bromostyrene, chlorostyrene, trichlorostyrene and the like These can be used alone or in combination. Of these, styrene can be preferably used.

The first core layer, the second core layer and the third core layer may further comprise a crosslinking agent. The crosslinking agent may be at least one selected from the group consisting of aryl methacrylate, triarylisocyanurate, triarylamine, aryl maleate, diaryl fumarate, diarylamine, divinylbenzene, trivinylbenzene, ethylene glycol dimethacrylate, diethylene glycol di Methacrylate, triethylene glycol dimethacrylate, 1,3-butanediol dimethacrylate, 1,6-hexanediol dimethacrylate, neopentyl glycol dimethacrylate, trimethylolpropane trimethacrylate, tri Methylol methane triacrylate, or a mixture thereof.

The first core layer may further comprise 0 to 0.05 parts by weight, preferably 0 to 0.03 part by weight, of the crosslinking agent relative to 100 parts by weight of the alkyl acrylate monomer contained in the core (A) Can be polymerized singly with an alkyl acrylate monomer without a cross-linking agent. The second core layer may further include 0.01 to 1 part by weight, preferably 0.01 to 0.5 part by weight, of a crosslinking agent based on 100 parts by weight of the alkyl acrylate monomer contained in the core (A). The third core layer may further include 0.01 to 1.5 parts by weight, preferably 0.01 to 1 part by weight, of a crosslinking agent based on 100 parts by weight of the alkyl acrylate monomer contained in the core (A). The content of the crosslinking agent contained in the third core layer is larger than the content of the crosslinking agent contained in the second core layer. When the content of the crosslinking agent exceeds the upper limit value, the impact reinforcing effect of the core (A) is lowered.

The first core layer, the second core layer and the third core layer may further comprise an emulsifier. The emulsifier may be a sulfonic emulsifier or a mixture thereof. Preferably dialkyl sulfosuccinates can be used. In the case of benzoic acid or alkylcarboxylic acid used as a conventional emulsifier, the alkyl moiety of the alkyl acrylate monomer used for the acrylic rubber-like polymer is substituted with the carboxylic acid moiety of the emulsifier and can not function as an emulsifier. However, the dialkyl sulfosuccinate can not function as an emulsifier until the octyl group is substituted, so that the dialkyl sulfosuccinate can function as an emulsifier without changing properties of the emulsifier.

The first core layer further comprises 0.01 to 1.0 part by weight of an emulsifier based on 100 parts by weight of the alkyl acrylate monomer contained in the core (A), and the second core layer comprises 100 parts by weight of the alkyl acrylate monomer contained in the core (A) And the third core layer may further comprise 0 to 1.0 part by weight of an emulsifier based on 100 parts by weight of the alkyl acrylate monomer contained in the core (A). When the content of the emulsifier is within the above range, the average particle diameter of the core can be controlled within the range of 50 to 500 nm, and the colorability of the acrylic rubber-modified graft copolymer can be improved. When the content of the emulsifier exceeds the upper limit value, the alkyl acrylate rubbery polymer does not aggregate and the core (A) can not be formed.

The first core layer, the second core layer and the third core layer may further comprise an electrolyte. The electrolyte may be potassium carbamate or an electrolyte mixture comprising the same.

The first core layer further comprises 0.01 to 1.0 part by weight of the electrolyte relative to 100 parts by weight of the alkyl acrylate monomer contained in the core (A), and the second core layer comprises 100 parts by weight of the alkyl acrylate monomer contained in the core (A) , And the third core layer may further comprise 0 to 1.0 part by weight of the electrolyte with respect to 100 parts by weight of the alkyl acrylate monomer contained in the core (A). When the content of the electrolyte is within the above range, the average particle diameter of the core can be controlled within the range of 50 to 500 nm, and the colorability of the acrylic rubber-modified graft copolymer can be improved.

The first core layer, the second core layer and the third core layer may further comprise a fat-soluble polymerization initiator. The polymerization initiator is preferably contained in an amount of 0.2 to 1 part by weight based on 100 parts by weight of the total alkyl acrylate monomer used in the core (A). When the content of the polymerization initiator is less than 0.2 part by weight, the desired grafting rate can not be achieved, unreacted monomers are increased, and a problem of excessive formation of the graft polymer may occur. On the other hand, when the content of the polymerization initiator is more than 1 part by weight, there is a problem that the polymerization system becomes unstable due to an increase in the reaction rate and the amount of the coagulum is increased.

The first core layer, the second core layer and the third core layer may further comprise ion-exchanged water.

The core (A) has a structure in which the cross-linking density gradually increases in the order of the first core layer, the second core layer and the third core layer. The cross-linking density gradually increases toward the outside of the core layer (A), thereby having a structure capable of maximizing the impact resistance. Due to the morphology of the acrylic rubber-like polymer, when the impact is applied from the outside, the structure is easily deformed and the structure of the rubber-like polymer can be deformed so as to absorb the impact energy.

The first core layer uses a polymer that is polymerized with an alkyl acrylate monomer having a weight average molecular weight of 1,000,000 to 10,000,000 g / mol. Since the polymer itself polymerized with an alkyl acrylate monomer has a low glass transition temperature and it is difficult to produce core particles, in order to give excellent impact resistance in the case of the first core which polymerizes singly the alkyl acrylate monomer alone, the weight average molecular weight The use of a polymer polymerized with a high alkyl acrylate monomer imparts rubber properties to the first core layer. As an alkyl acrylate monomer 　 When the weight average molecular weight of the polymerized polymer is less than 1,000,000 g / mol, no core particles are produced. When the polymerized polymer is more than 10,000,000 g / mol, 　 The polymerization of the polymerized polymer is difficult and the polymerization time is long.

The second core layer and the third core layer can maintain the spherical particle shape of the core (A) by lowering the deformation degree of the polymer polymerized with the alkyl acrylate monomer by copolymerizing the alkyl acrylate monomer and the minimum aromatic vinyl monomer.

The core (A) has a weight average molecular weight of 1,000,000 to 10,000,000 g / mol. When the weight average molecular weight of the core (A) is less than 1,000,000 g / mol, the spherical particle type core (A) can not be formed.

The core (A) preferably has an average particle diameter of 50 to 500 nm, a gel content of 70 to 95% by weight, and a swelling index of 5 to 20. More preferably, the average particle diameter of the core (A) is 10 to 350 nm. When the average particle diameter of the core (A) is less than 50 nm, the impact reinforcing effect is deteriorated. When the core (A) has an average particle diameter of more than 500 nm, the impact reinforcing effect is somewhat increased, but when the graft copolymer is manufactured, the polymerization stability is deteriorated, , And the fluidity, glossiness and coloring property of the final molded product can be deteriorated.

The core (A) can be improved in coloring property by using a tri-core acrylic rubber-like polymer having a particle size distribution of unimodal or by graft copolymerizing an aromatic vinyl-unsaturated nitrile monomer mixture which is a shell (B) A bimodal or trimodal tri-core acrylic rubber polymer having different average particle diameters may be mixed and used.

(B) shell

The present invention relates to an aromatic vinyl-unsaturated nitrile-based copolymer in which an aromatic vinyl monomer and an unsaturated nitrile monomer mixture are graft-copolymerized in the core (A) or an alkyl (meth) acrylate-based copolymer in which an alkyl (meth) To form a polymer shell (B).

The aromatic vinyl-unsaturated nitrile-based copolymer or alkyl (meth) acrylate-based copolymer has a weight average molecular weight of 50,000 to 500,000 g / mol, and preferably 100,000 to 300,000 g / mol. By using an aromatic vinyl-unsaturated nitrile-based copolymer or an alkyl (meth) acrylate-based copolymer having a high weight average molecular weight in the shell (B), the degree of deformation of the acrylic rubber-like polymer core is lowered and the acrylic rubber- It keeps it in particle form.

The aromatic vinyl monomer may be at least one selected from the group consisting of side chain alkyl-substituted styrenes such as styrene, alpha -ethylstyrene and alpha -methylstyrene, and alkyl-substituted styrenes such as p-methylstyrene and ot-butylstyrene, bromostyrene, chlorostyrene, trichlorostyrene, These can be used alone or in combination. Of these, styrene may be preferably used.

Examples of the unsaturated nitrile-based monomer include acrylonitrile, methacrylonitrile, and fumaronitrile, which may be used alone or in combination. Of these, acrylonitrile can be preferably used.

The aromatic vinyl-unsaturated nitrile-based copolymer preferably forms a shell (B) by graft copolymerizing 20 to 90% by weight of an aromatic vinyl monomer and 10 to 80% by weight of an unsaturated nitrile monomer mixture to the core (A).

The alkyl (meth) acrylate-based copolymer may further contain 50 to 100% by weight of an alkyl (meth) acrylate monomer and 0 to 50% by weight of the alkyl (meth) Can be graft copolymerized with the core (A) to form the shell (B).

The alkyl (meth) acrylate monomer is preferably an alkyl (meth) acrylate having 2 to 20 carbon atoms, such as methyl acrylate, ethyl acrylate, propyl acrylate, isopropyl acrylate, t-butyl acrylate, n-octyl acrylate, 2-ethylhexyl acrylate, or alkyl acrylate monomers such as methyl methacrylate, ethyl methacrylate, propyl methacrylate, isopropyl methacrylate, t-butyl methacrylate, n- Methacrylate, n-octyl methacrylate, and 2-ethylhexyl methacrylate. These monomers may be used singly or in combination. Of these, methyl methacrylate, methyl acrylate or a mixture thereof can be preferably used. When methyl methacrylate and methyl acrylate are used at the same time, methyl acrylate can prevent depolymerization of methyl methacrylate.

Hereinafter, the method for producing the acrylic rubber-modified graft copolymer of the present invention will be described in detail.

Acrylic Rubber Modification Graft  Process for producing a copolymer

Step 1 - Preparation of Core (A)

The method for producing the core layer (A) of the present invention comprises the steps of: (a) adding 10 to 50% by weight of an alkyl acrylate to 100% by weight of the entire alkyl acrylate monomer in the core layer (A) Exchanged water is added and stirred to raise the reaction temperature to 55 to 65 DEG C and then the polymerization initiator is added to maintain the polymerization temperature at 70 to 75 DEG C to form the first core layer; (b) Core layer (A) 25 to 45% by weight of an alkyl acrylate based on 100% by weight of the whole alkyl acrylate monomer, 0.01 to 70% by weight of an aromatic vinyl monomer based on 100 parts by weight of the alkyl acrylate monomer used in the second core layer (A) 0.01 to 1 part by weight of a crosslinking agent is added to 100 parts by weight of an alkyl acrylate monomer as a whole, and then an emulsifier, an electrolyte and ion exchange water are added thereto and stirred to adjust the reaction temperature to 55 to 65 ° C , Adding a polymerization initiator to maintain the polymerization temperature at 70 to 75 占 폚 to form a second core layer; And (c) 25 to 45% by weight of an alkyl acrylate based on 100% by weight of the entire alkyl acrylate monomer as the core layer (A), 0.01 to 50% by weight of an aromatic vinyl monomer as an aromatic vinyl monomer with respect to 100 parts by weight of the alkyl acrylate monomer used in the third core layer, And 0.01 to 1.5 parts by weight of a cross-linking agent are added to the reactor in an amount of 100 parts by weight based on 100 parts by weight of the alkyl acrylate monomer as the core layer (A), and then the emulsifier, electrolyte and ion- , And then adding a polymerization initiator to maintain the polymerization temperature at 70 to 75 占 폚 to form a third core layer.

Step 2 - The shell (B)  formation

Emulsifier and ion-exchanged water are charged into 30 to 80 parts by weight of the core (A), the temperature is raised while stirring, and a fat-soluble polymerization initiator is added when the internal temperature of the reactor reaches 50 to 60 占 폚. Thereafter, 20 to 70 parts by weight of a monomer mixture containing 20 to 90% by weight of an aromatic vinyl monomer and 10 to 80% by weight of an unsaturated nitrile monomer are mixed and stirred together with a molecular weight adjuster. Then, the core (A) For 5 hours to form the shell (B), whereby the acrylic rubber-modified graft copolymer of the present invention is completed.

In place of the aromatic vinyl monomer and the unsaturated nitrile monomer, 50 to 100% by weight of an alkyl (meth) acrylate monomer and 0 to 50% by weight of an alkyl (meth) acrylate monomer different from the alkyl (meth) acrylate monomer may be used .

In forming the core (A) and the shell (B), a redox-based catalyst or a pyrolysis catalyst may further be used. As the redox-based catalyst, it is preferable to mix 0.0005 to 0.006 parts by weight of ferrous sulfate, 0.01 to 0.15 parts by weight of sodium pyrophosphate, and 0.05 to 0.15 parts by weight of dextrose. As the pyrolysis catalyst, a fat-soluble polymerization initiator can be used.

The components used in the polymerization using the catalyst will be described as follows.

The contents of the alkyl acrylate monomers, aromatic vinyl monomers, unsaturated nitrile monomers, alkyl (meth) acrylate monomers and additives can all be applied to the above-mentioned method for producing an acrylic rubber-modified graft copolymer. In order to avoid duplication, do.

Polycarbonate resin composition

The present invention provides a polycarbonate resin composition comprising the acrylic rubber-modified graft copolymer and a polycarbonate resin.

The polycarbonate resin may be any of the polycarbonate resins well known to those skilled in the art. Since the content of the aromatic vinyl monomer in the core (A) is high, the acrylic rubber-modified graft copolymer has almost the same refractive index as the polycarbonate resin, so that the colorability of the polycarbonate resin composition can be improved.

The polycarbonate resin composition according to the present invention can be produced by a known method for producing a resin composition. For example, the components of the present invention and other additives may be simultaneously mixed and then melt-kneaded in an extruder to produce pellets or chips.

The content of the acrylic rubber-modified graft copolymer may be all applied to a polycarbonate resin composition, and is omitted in order to avoid duplication.

Molded product

The present invention provides a molded article produced from the polycarbonate resin composition.

There is no particular limitation on the method of molding the molded article, and extrusion, injection molding or casting molding methods can be applied. Such molding can be easily carried out by a person having ordinary skill in the art to which the present invention belongs.

The molded article of the present invention had an Izod impact strength of 40 to 47 kgf · cm / cm measured at a temperature of 23 ° C. and a thickness of 1/4 "in accordance with ASTM D256, and a temperature of 23 ° C. and a ratio of 1/8" The Izod impact strength measured at the thickness is 57 to 70 kgf · cm / cm.

The molded product has a melt flow index (MI) of 19 to 25 g / 10 min measured at a temperature of 200 캜 and a load of 5 kg according to ASTM D1238.

The molded product has a Vicat softening point measured in accordance with ISO 306 / B50 of 94 to 97 占 폚.

In the case of black, the molded product has an L value of 27 to 30, a value of -0.1 to 0.2, and an L value measured according to the International Lighting Committee (CIE) Lab using a CM-3500d spectrophotometer of Minolta Co., Value is -1.3 to -0.1.

The content of the polycarbonate resin composition can be all applied to a molded article and is omitted in order to avoid duplication.

Example

The specifications of each component used in the production examples of the present invention, comparative preparation examples, examples and comparative examples are as follows.

Manufacturing example One

Stage 1 - The core layer (A)  formation

10 parts by weight of butyl acrylate was added to the reactor, and 0.5 part by weight of the emulsifier, 0.1 part by weight of the electrolyte and 150 parts by weight of ion-exchanged water were added to 100 parts by weight of the butylacrylate and stirred. After the temperature was raised, a polymerization initiator was added and the polymerization temperature was maintained at 60 캜 to form a first core layer. To the produced first core layer, 45 weight% of butyl acrylate, 15 weight parts of styrene with respect to 100 weight parts of the butylacrylate monomer and 0.2 weight parts of aryl methacrylate as a crosslinking agent were added to the reactor. At this time, 0.5 part by weight of the emulsifier and 0.1 part by weight of the electrolyte were charged and stirred to raise the reaction temperature to 70 DEG C, and then the polymerization initiator was added to maintain the polymerization temperature at 70 DEG C to form the second core layer. To the produced second core layer, 45 weight% of butyl acrylate, 15 weight parts of styrene with respect to 100 weight parts of the butylacrylate monomer and 0.6 weight parts of aryl methacrylate as a crosslinking agent were added to the reactor. At this time, 0.5 part by weight of the emulsifier and 0.1 part by weight of the electrolyte were charged and stirred to raise the reaction temperature to 70 DEG C, and then the polymerization initiator was added to maintain the polymerization temperature at 70 DEG C to form the third core layer.

Step 2 - The shell (B)  formation

60 parts by weight of the core (A) prepared above was charged with 0.5 part by weight of an emulsifier and 50 parts by weight of ion-exchanged water, and the temperature was elevated while stirring. Then, when the internal temperature of the reactor reached 70 DEG C, 0.1 part by weight of a fat- Then, 40 parts by weight of a monomer mixture containing 95% by weight of methyl methacrylate and 5% by weight of methyl acrylate was mixed with 0.01 part by weight of a molecular weight adjuster and stirred. Then, a water-soluble polymerization initiator was added thereto, To form the shell (B), whereby the acrylic rubber-modified graft copolymer of the present invention was completed.

Manufacturing example 2 to 3

An acrylic rubber-modified graft copolymer was prepared in the same manner as in Preparation Example 1 with the contents shown in Table 1 below.

Comparative Manufacturing Example  1 to 3

The same procedure as in Production Example 1 was carried out except that styrene was not used in the core (A) but no butyl acrylate was used in the production of the third core layer, , An acrylic rubber-modified graft copolymer was prepared.

In Table 1, butyl acrylate of the first to third core layers is expressed in terms of% by weight based on 100% by weight of butyl acrylate as a whole of the core layer, and styrene and aryl methacrylate The rates are expressed in parts by weight relative to 100 parts by weight of butyl acrylate of the first, second and third core layers, respectively, and the methyl methacrylate and methyl acrylate of the shell are methyl methacrylate and methyl acrylate By weight based on 100% by weight.

Manufacturing example Comparative Manufacturing Example One 2 3 One 2 3 (A) Core Butyl acrylate 1 core layer 10 30 30 20 20 20 2 core layer 45 35 35 80 80 80 3 core layer 45 35 35 - - - Styrene 1 core layer - - - - - - 2 core layer 15 15 15 - - - 3 core layer 15 15 15 - - - Aryl methacrylate
(Crosslinking agent) 1 core layer - - - 0.1 0.1 0.1 2 core layer 0.2 0.2 0.2 0.4 0.4 0.4 3 core layer 0.6 0.6 0.6 0.4 0.4 0.4 Average particle diameter (nm) 100 200 300 100 200 300 (B) shell Methyl methacrylate 95 95 95 95 95 95 Methyl acrylate 5 5 5 5 5 5

Example  1-3 and Comparative Example  1-3

25% by weight of the acrylic rubber-modified graft copolymer prepared in Production Examples 1 to 3 and Comparative Production Examples 1 to 3, 75% by weight of a polycarbonate resin, and 100 parts by weight of an acrylic rubber-modified graft copolymer and a polycarbonate resin 1 part by weight of carbon black as a black pigment was mixed and extruded / processed to obtain a thermoplastic resin composition in the form of a pellet. The extrusion was carried out using a twin-screw extruder with L / D = 29 and a diameter of 45 mm, and the barrel temperature was set at 260 캜. The pellets were dried at 80 DEG C for 2 hours, and then subjected to a 6 Oz injection molding machine to prepare test specimens having a size of 9 cm x 5 cm x 0.2 cm at a cylinder temperature of 250 deg. C and a mold temperature of 60 deg. After the specimens were prepared, the impact strength, melt flow index, softening point of viscose and colorability were measured and the results are shown in Table 2.

(1) Izod impact strength (notched, kgf · cm / cm): Measured according to ASTM D256 at a temperature of 23 ° C and a thickness of 1/4 "and 1/8".

(2) Melt flow index (g / 10 min): Measured according to ASTM D1238 at a temperature of 200 캜 and a load of 5 kg.

(3) Vicat softening point (占 폚): Measured according to ISO 306 B / 50.

(4) Coloring property: The L value, a value, and b value were measured in accordance with the International Lighting Committee (CIE) Lab using a CM-3500d spectrophotometer of Minolta Co., Ltd. In the case of black, since the blackness is higher as the L value indicating brightness is smaller, it can be judged that the coloring property is excellent.

Example Comparative Example One 2 3 One 2 3 Izod
Impact strength 1/4 " 43.8 44.0 44.8 35.2 38.1 38.5 1/8 " 60.0 64.7 66.1 50.4 53.8 54.2 Melt flow index 19.8 22.0 23.8 19.9 21.5 24.0 Beckett softening point 94.5 95.0 95.9 117.0 117.0 95.4 Colorability L value 27.5 27.9 28.7 28.5 29.2 30.3 a value -0.1 0.1 0.2 -0.1 0.1 0.2 b value -1.2 -0.8 -0.3 -1.5 -1.1 -0.6

In Examples 1 to 3 using a styrene monomer for the second core layer and the third core layer without using a crosslinking agent in the production of the first core layer, a crosslinking agent was used in the production of the first core layer, The impact strength, fluidity, heat resistance and coloring property were superior to those of Comparative Examples 1 to 3 in which the styrene monomer was not used in the three-core layer.

It will be understood by those skilled in the art that various changes in form and details may be made therein without departing from the spirit and scope of the invention as defined by the appended claims.

Claims (21)

(A) a first core layer obtained by polymerizing an alkyl acrylate monomer, a second core layer obtained by copolymerizing an alkyl acrylate monomer and an aromatic vinyl monomer, and a third core layer copolymerized with an alkyl acrylate monomer and an aromatic vinyl monomer core; And
(B) a graft copolymerized monomer mixture comprising an alkyl (meth) acrylate monomer;
Wherein the core (A) has an increased cross-linking density from the first core layer to the third core layer, and has an average particle diameter of 50 to 500 nm.
The method according to claim 1, 　 Wherein the acrylic rubber-modified graft copolymer comprises 30 to 80% by weight of core (A) and 20 to 70% by weight of shell (B).
The method of claim 1, wherein the core (A) comprises 10 to 50 wt% of the first core layer, 25 to 45 wt% of the second core layer, and 25 to 45 wt% of the third core layer By weight of an acrylic rubber-modified graft copolymer.
The method of claim 1, wherein the second core layer comprises 80-99 wt% alkyl acrylate monomers and 1-20 wt% aromatic vinyl monomers, the third core layer comprises 80-99 wt% alkyl acrylate monomers and 1 to 20% by weight of an aromatic vinyl monomer, based on the total weight of the acrylic rubber-modified graft copolymer.
The acrylic rubber modified graft copolymer according to claim 1, wherein the first core layer, the second core layer, and the third core layer further comprise a crosslinking agent, an emulsifier, or a mixture thereof.
6. The method of claim 5, wherein the first core layer further comprises 0 to 0.05 parts by weight of the crosslinking agent relative to 100 parts by weight of the alkyl acrylate monomer contained in the core (A) Wherein the third core layer further comprises 0.01 to 1 part by weight of the cross-linking agent based on 100 parts by weight of the alkyl acrylate monomer contained in the core (A) Wherein the crosslinking agent further comprises 0.01 to 1.5 parts by weight of the crosslinking agent.
6. The composition of claim 5, wherein the emulsifier is selected from the group consisting of a sulfonic emulsifier and a mixture thereof, wherein the first core layer comprises the emulsifier 0.01 (based on 100 parts by weight of the alkyl acrylate monomer) Wherein the second core layer further comprises 0 to 1.0 part by weight of the emulsifier based on 100 parts by weight of the alkyl acrylate monomer contained in the core A, Further comprising 0 to 1.0 part by weight of the emulsifier based on 100 parts by weight of the alkyl acrylate monomer contained in the core (A).
2. The method of claim 1, wherein the first core layer, the second core layer and the third core layer further comprise a potassium carbamate or an electrolyte mixture comprising the same, Wherein the second core layer further comprises 0.01 to 1.0 part by weight of the electrolyte relative to 100 parts by weight of the alkyl acrylate monomer contained in the core, Wherein the third core layer further comprises 0 to 1.0 part by weight of the electrolyte relative to 100 parts by weight of the alkyl acrylate monomer contained in the core (A) Copolymer.
The acrylic rubber-modified graft copolymer according to claim 1, wherein the core (A) has a weight average molecular weight of 1,000,000 to 10,000,000 g / mol.
The acrylic rubber-modified graft copolymer according to claim 1, wherein the alkyl acrylate monomer is an alkyl acrylate monomer having 2 to 20 carbon atoms.
The method according to claim 1, wherein the aromatic vinyl monomer is selected from the group consisting of styrene,? -Ethylstyrene,? -Methylstyrene, p-methylstyrene, ot-butylstyrene, bromostyrene, chlorostyrene, trichlorostyrene, Wherein the acrylic rubber-modified graft copolymer is at least one selected from the group consisting of acrylic rubber-modified graft copolymers and acrylic rubber-modified graft copolymers.
delete The acrylic rubber-modified graft copolymer according to claim 1, wherein the alkyl (meth) acrylate monomer is an alkyl (meth) acrylate monomer having 2 to 20 carbon atoms.
delete The composition of claim 1, wherein the shell (B) comprises 50 to 100% by weight of an alkyl (meth) acrylate monomer and 0 to 50% by weight of an alkyl (meth) acrylate monomer different from the alkyl (meth) Wherein the acrylic rubber-modified graft copolymer is an acrylic rubber-modified graft copolymer.
A polycarbonate resin composition comprising an acrylic rubber-modified graft copolymer and a polycarbonate resin according to any one of claims 1 to 11, 13 and 15.
16. A molded article made from the polycarbonate resin composition of claim 16.
The molded article according to claim 17, wherein the molded article has an Izod impact strength of 40 to 47 kgf · cm / cm measured at a temperature of 23 ° C and a thickness of 1/4 "according to ASTM D256, a temperature of 23 ° C / 8 "is 57 to 70 kgf cm / cm. ≪ / RTI >
The molded article according to claim 17, wherein the molded product has a melt flow index of 19 to 25 g / 10 min measured at a temperature of 200 캜 and a load of 5 kg according to ASTM D1238, and a softening point of beaker measured according to ISO 306 B / Lt; RTI ID = 0.0 > 97 C. < / RTI >
The molded article according to claim 17, wherein the molded article is black and has an L value of 27 to 30 and a value of -0.1 to 0.2 as measured according to the International Lighting Committee (CIE) Lab using a CM-3500d spectrophotometer of Minolta Co. , and the b value is -1.3 to -0.1.
A method for producing an acrylic rubber-modified graft copolymer having a core-shell structure,
(1) polymerizing an alkyl acrylate monomer to form a first core layer; (2) copolymerizing the alkyl acrylate monomer and the aromatic vinyl monomer in the first core layer to form a second core layer; And (3) copolymerizing the alkyl acrylate monomer and the aromatic vinyl monomer in the second core layer to form a third core layer,
A process for producing an acrylic rubber-modified graft copolymer, which comprises graft-copolymerizing an alkyl (meth) acrylate monomer with the core to form a shell.