KR20070019411A - Process for preparing graft copolymer - Google Patents

Abstract

The present invention relates to a method for preparing a graft copolymer, and more particularly, to prepare an alkyl acrylate core comprising a hard polymer seed from an acrylate rubber polymer through an acid-enlarging process, in the presence of the acrylate rubber polymer. It relates to a method for producing an acrylate-styrene-acrylonitrile (ASA) graft copolymer comprising the step of preparing a graft shell, ASA graft copolymer and styrene prepared by the above method -Thermoplastic resin with excellent weathering resistance and excellent impact strength, tensile strength, fluidity, gloss and thermal stability by mixing acrylonitrile (SAN) resin and at the same time very excellent pigment coloring compared with conventional ASA thermoplastic resin composition It has the effect of providing a composition.

Graft copolymer, Alkyl acrylate rubber polymer, Styrene-acrylonitrile resin, Weather resistance, Pigment coloring, Saturation of acid

Description

Method for producing a graft copolymer {METHOD FOR PREPARING GRAFT COPOLYMER}

The present invention relates to a method for preparing a graft copolymer, and more particularly, to prepare an alkyl acrylate core comprising a hard polymer seed from an acrylate rubber polymer through an acid-enlarging process, in the presence of the acrylate rubber polymer. It relates to a method for producing an acrylate-styrene-acrylonitrile (ASA) graft copolymer comprising the step of preparing a graft shell, the prepared ASA graft copolymer and styrene-acrylonitrile (SAN) The present invention relates to a thermoplastic resin composition in which a resin is mixed and excellent in impact resistance, tensile strength, flowability, gloss, and thermal stability, as well as excellent pigment coloring property.

Acrylonitrile-butadiene-styrene (hereinafter referred to as "ABS"), methylmethacrylate-butadiene-styrene (hereinafter referred to as "MBS") prepared via emulsion polymerization, acrylate-styrene-acrylonitrile (hereinafter referred to as " ASA ") and acrylic impact modifiers (hereinafter referred to as" AIM ") resins are excellent in impact resistance, rigidity, fluidity, etc., and are widely used in various plastic modifiers.

In particular, ABS resin is excellent in dimensional stability, processability, and chemical resistance, and is widely used as a material for a monitor housing, a game housing, a home appliance, an office device, and an automobile lamp housing.

However, the product has excellent impact resistance at low temperatures, but the use of butadiene polymer as a rubber has a problem that it is not suitable for outdoor materials due to the poor weatherability and aging resistance.

Therefore, in order to obtain a product having not only high impact strength but also excellent weatherability and aging resistance, there should be no ethylenically unsaturated polymer in the graft copolymer. ASA polymers using representatively crosslinked alkyl acrylate rubber polymers are known to be suitable. Such ASA resin has excellent weather resistance and aging resistance, and is used in various fields such as automobiles, ships, leisure products, building materials, and gardening.

German Patent No. 1,260,135 discloses a process for preparing ASA polymers excellent in weatherability and aging resistance, wherein the core used is a large diameter latex of crosslinked acrylate having an average particle diameter of 150 to 800 nm and a narrow particle size distribution. Compared to polymers prepared using small diameter polyacrylate latex, polymers comprising large diameter polyacrylate latex have improved notch impact strength, greater hardness and reduced shrinkage. However, the large diameter graft copolymer has a disadvantage in that coloring is difficult compared to the small diameter graft copolymer. The use of the corresponding ASA polymers for producing colored moldings is limited, i.e. a pale pastel color is obtained rather than a light color.

U.S. Pat. No. 4,224,419 describes a crosslinked acrylate polymer having an average particle diameter of about 50 to 150 nm as a core, a styrene and acrylonitrile as a graft shell, in a weather resistant high impact thermoplastic resin that can be easily colored. First graft copolymer, a crosslinked acrylate polymer having an average particle diameter of about 200 to 500 nm as a core, a second graft copolymer separately prepared from styrene and acrylonitrile as a graft shell, and acrylonitrile And a hard component comprising a copolymer of styrene or α-methylstyrene, wherein the weight ratio between the core components is 90:10 to 35:65 and the ratio of the sum of the two core components is about 10 to 35 based on the mixture A molding material which is part by weight is disclosed.

On the other hand, European Patent No. 534,212 and U.S. Patent No. 5,932,655 prepare a large-diameter and small-diameter graft copolymer, respectively, and prepare a hard component having a glass transition temperature higher than room temperature as a seed component to improve coloring and impact resistance. It is starting. In European Patent No. 534,212, hard seeds were used only for small diameter graft copolymers, and in US Pat. No. 5,932,655, hard polystyrene seeds were used for both large diameter and small diameter graft copolymers.

The known materials are excellent in weatherability and mechanical properties and have improved colorability. However, the coloring improvement effect of these materials is still insufficient. These materials used alkyl acrylate polymers crosslinked with rubber components, and the refractive index of the alkyl acrylate was too low in comparison with styrene and acrylonitrile, so that a very vivid color could not be realized in coloring.

In order to overcome this disadvantage, a method of using a multilayer alkyl acrylate rubber polymer containing a diene rubber polymer therein is disclosed in Japanese Patent Application Laid-Open No. 47-47863, Japanese Patent Application Laid-Open No. 59-49245, and Japanese Patent Application Laid-Open No. 3-66329, U.S. Patent Nos. 4,912,162 and 4,393,172. However, the above-mentioned patent has a disadvantage in that the diene-based polymer inner layer is not sufficiently stacked in the alkyl acrylate polymer outer layer and is not suitable for producing a resin having extremely excellent weather resistance.

In order to solve the problems of the prior art as described above, the present invention is a graft prepared in the presence of the acrylate rubber polymer prepared in the presence of the acrylate rubber polymer alkyl acrylate core comprising a hard polymer seed through an acid-enlarging process It is an object of the present invention to provide a method for preparing an ASA graft copolymer comprising the step of preparing a shell.

In addition, an object of the present invention is to provide a thermoplastic resin composition comprising an ASA graft copolymer and a SAN resin produced by the above production method.

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

In order to achieve the above object, the present invention

(a) preparing a hard polymer seed;

(b) preparing an alkyl acrylate core in the presence of the hard polymer seed of (a);

(c) preparing an acrylate rubber polymer by acid-enlarging the core of (b); And

(d) preparing a graft shell in the presence of the acrylate rubber polymer of (c);

It provides a method for producing an ASA graft copolymer comprising a.

The graft copolymer is 5 to 25 parts by weight of a monomer selected from the group consisting of aromatic vinyl compounds, vinyl cyan compounds and methyl methacrylate, 0.05 to 0.3 parts by weight of an electrolyte, 0.01 to 0.5 parts by weight of a crosslinking agent and a grafting agent Hard polymer seeds prepared by polymerizing 0.01 to 0.5 parts by weight and 0.05 to 4 parts by weight of surfactant;

Alkyl prepared by polymerizing 20 to 70 parts by weight of alkyl acrylate, 0.05 to 0.3 part by weight of electrolyte, 0.1 to 1 part by weight of crosslinking agent, 0.05 to 0.5 part by weight of grafting agent and 0.05 to 4 parts by weight of surfactant in the presence of the hard polymer seed Acrylate cores;

An acrylate rubber polymer prepared through an acid-enlarging process of the alkyl acrylate core; And

A graft shell prepared by polymerizing 10 to 50 parts by weight of aromatic vinyl compound, 5 to 25 parts by weight of vinyl cyan compound, and 0.05 to 4 parts by weight of surfactant in the presence of the acrylate rubber polymer;

It may be made, including.

ASA graft copolymer resin having excellent weather resistance tends to be inferior to ABS resins in colorability. To overcome this problem, a small diameter ASA resin is introduced to mix small and large diameters, and colorability using hard polymer seeds. Although the method of raising is used, although it has a considerable effect on coloring property, there exists a problem that a notch impact strength falls. Therefore, in the present invention, an alkyl acrylate rubber polymer latex including a hard polymer seed is grown through an acid-enlarging process, so that both the colorability of the hard polymer seed and the mechanical properties of the acid-enriched alkyl acrylate rubber polymer are excellent. Copolymers can be prepared.

A method for preparing the ASA graft copolymer of the present invention is a method of preparing an copolymer of an acrylate rubber polymer-grafted shell structure through an acid-enlarging process of an alkyl acrylate rubber polymer including a hard polymer seed.

Hereinafter, the present invention will be described in detail.

(a) Preparation of Hard Polymer Seeds

The component of the hard polymer seed used in the present invention consists of a hard polymer having a glass transition temperature of at least 60 ° C., wherein the hard polymer is based on 100 parts by weight of the total monomers used for preparing the graft copolymer, and has monomers of 5 to 25. The polymer is prepared by adding 0.05 to 0.3 parts by weight of an electrolyte, 0.01 to 0.5 parts by weight of a crosslinking agent, 0.01 to 0.5 parts by weight of a grafting agent, and 0.05 to 4 parts by weight of a surfactant.

As the monomer for producing the hard polymer, a compound containing a unit derived from an aromatic vinyl compound, a vinyl cyan compound, methyl methacrylate, or the like is preferably used alone or in combination of two or more thereof.

As the aromatic vinyl compound, styrene derivatives are preferably used, and styrene, α-methylstyrene, p-methylstyrene, vinyltoluene or substituents thereof may be used.

As the vinyl cyan compound, acrylonitrile, methacrylonitrile, ethacrylonitrile and the like can be used.

The electrolyte may be used NaHCO ₃ , Na ₂ S ₂ O ₇ or K ₂ CO ₃ , it is preferable to use NaHCO ₃ .

The crosslinking agent is ethylene glycol dimethacrylate, diethylene glycol dimethacrylate, triethylene glycol dimethacrylate, 1,3-butanediol dimethacrylate, 1,6-hexanediol dimethacrylate, neopentyl glycol Dimethacrylate, trimethylol propane trimethacrylate, trimethylol methane triacrylate, and the like can be used.

The grafting agent may be aryl methacrylate (AMA), triaryl isocyanurate (TAIC), triaryl amine (TAA) or diaryl amine (DAA).

Although the type of the surfactant is not particularly limited, in order to facilitate the preparation of the rubber polymer through the acid-enlarging process of the hard polymer and the core including the hard polymer, oleic acid, stearic acid, lauric acid, Fatty acid soap systems typified by sodium or potassium salts of mixed fatty acids, rosin acid soaps typified by abietin acid salts, and the like can be used alone or in combination of two or more thereof.

For the reaction of the hard polymer, emulsion polymerization alone or a method of mixing emulsion-free polymerization and emulsion polymerization may be used. The monomer addition method may be used alone or in combination of batch injection and continuous injection, respectively.

It is preferable that the average particle diameter of the said hard polymer seed is 50-100 nm.

(b) preparing an alkyl acrylate core

The component of the core used in the present invention is a crosslinked alkyl acrylate rubber polymer having a glass transition temperature of less than 0 ° C, more preferably having a glass transition temperature of -20 to -70 ° C. The glass transition temperature of the alkyl acrylate rubber polymer can be measured by the DSC method.

The crosslinked alkyl acrylate rubber polymer may be 20 to 70 parts by weight of alkyl acrylate monomers and 0.05 to 0.3 parts by weight of electrolyte based on 100 parts by weight of the total monomers used for preparing the graft copolymer to the hard polymer seed of (a). It is prepared by adding 0.1 to 1 parts by weight of crosslinking agent, 0.05 to 0.5 parts by weight of grafting agent and 0.05 to 4 parts by weight of surfactant.

The alkyl acrylate monomer may be an alkyl acrylate having 2 to 8 carbon atoms in the alkyl portion, preferably to use an alkyl acrylate having 4 to 8 carbon atoms, more preferably butyl acrylate Or ethyl hexyl acrylate.

The electrolyte, crosslinking agent, grafting agent and surfactant are the same as those used for preparing the hard polymer seed of (a).

The reaction for producing the crosslinked alkyl acrylate rubber polymer is the same as the method used for preparing the hard polymer seed of (a).

The average particle diameter of the crosslinked alkyl acrylate core is preferably 80 to 250 nm, more preferably 100 to 180 nm.

(c) preparing the acrylate rubber polymer

The prepared alkyl acrylate rubber polymer of (b) is diluted with an appropriate amount of distilled water so that the concentration of the solid is 20 to 50 parts by weight. 0.1 to 10 parts by weight of an acidic substance is added to the mixed latex in which the concentration of the solid is adjusted to increase the particle size.

The concentration of the solids in the mixed latex diluted with distilled water is preferably 20 to 50 parts by weight. If the concentration of the solid is less than 20 parts by weight, the amount of coagulant is reduced, but there is a problem that the particle size is reduced after the enlargement reaction, if the amount exceeds 50 parts by weight there is a problem that the amount of coagulant is increased.

The acidic substance is not particularly limited, but hydrochloric acid, sulfuric acid, acetic acid, phosphoric acid, hydrochloric acid, nitric acid, propionic acid, benzoic acid, formic acid, citric acid, lactic acid, maleic acid, or an acid group-containing monomer acrylic acid, methacrylic acid, ita Copolymer latex containing cholic acid, maleic acid, fumaric acid, crotonic acid, styrene sulfonic acid and the like can be used.

The acidic material is preferably used in an amount of 0.1 to 10 parts by weight depending on the average particle diameter of the alkyl acrylate rubber polymer, and in order to suppress the generation of coagulants, the concentration is preferably adjusted to 0.5 to 10% by weight.

The acrylate rubber polymer prepared through the acid enlargement process is preferably an average particle diameter of 200 to 500 nm, gel content of 50 to 95%. If the average particle diameter is less than 200 nm, there is a problem that the impact strength is lowered, if it exceeds 500 nm there is a problem that the colorability and tensile strength is lowered.

(d) manufacturing step of graft shell

The component of the graft shell used in the present invention is a copolymer of an uncrosslinked aromatic vinyl compound-vinyl cyan compound, and based on 100 parts by weight of the total monomers used for preparing the graft copolymer, the acid enlargement of (c) above. In the presence of 30 to 80 parts by weight of the processed acrylate rubber polymer (based on solids), 10 to 50 parts by weight of aromatic vinyl compound, 5 to 25 parts by weight of vinyl cyan compound, and 0.05 to 4 parts by weight of surfactant are prepared and polymerized. .

The said aromatic vinyl compound is the same as what was used at the time of preparation of the seed of (a) and the core of (b), and styrene is preferable.

The vinyl cyan compound is the same as that used in the preparation of the seed of (a) and the core of (b), with acrylonitrile being preferred.

In the preparation of the graft shell, maleimide, N-methylmaleimide, N-ethylmaleimide, N-propylmaleimide, N-phenylmaleimide, methyl methacrylate as a third monomer in addition to the aromatic vinyl compound and the vinyl cyan compound And a small amount of vinyl monomers such as methyl acrylate, butyl acrylate, acrylic acid or maleic anhydride can be used.

The surfactant is a derivative of an alkyl sulfo succinate metal salt having a pH of 3 to 9 and a carbon number of 12 to 18 or an alkyl sulfate ester having a carbon number of 12 to 20 as used in the preparation of the seed of (a) and the core of (b). Or derivatives of sulfonic acid metal salts.

Examples of the derivative of the alkyl sulfo succinate metal salt having 12 to 18 carbon atoms include dicyclohexyl sulfo succinate, dihexyl sulfo succinate, di 2-ethyl hexyl sulfo succinate sodium salt and di 2-ethylhexyl sulfo succinate potassium salt. , Dioctyl sulfo succinate sodium salt, or dioctyl sulfo succinate potassium salt can be used.

Examples of the alkyl sulfate ester or sulfonic acid metal salt having 12 to 20 carbon atoms include sodium lauryl sulfate, sodium dodecyl sulfate, sodium dodecyl benzene sulfate, sodium octadecyl sulfate, sodium oleic sulfate, potassium dodecyl sulfate or potassium. Octadecyl sulfate and the like can be used.

In the reaction of the graft shell, emulsion polymerization is preferable, and when the mixed monomer including the surfactant is added at the time of the graft reaction, the pH of the polymerization system is temporarily increased, so that the grafting is difficult and the stability of the particles is lowered. Since the internal structure of the particles is not uniform, it is preferable to use a continuous addition method for the addition of the mixed monomer including the surfactant during the graft reaction.

Molecular weight regulators may be used to control the molecular weight during seed, core and graft shell polymerization of the graft copolymer resin of the present invention, and it is preferable to use a tertiary dodecyl mercaptan.

Inorganic or organic peroxide compounds may be used as an initiator in the seed, core and graft shell polymerization of the graft copolymer resin of the present invention, and water-soluble initiators including potassium persulfate, sodium persulfate, ammonium persulfate, and the like, or cumene Oil-soluble initiators including hydroperoxide, benzoyl peroxide and the like can be used.

The initiator is preferably used 0.05 to 0.5 parts by weight based on 100 parts by weight of the total monomers used to prepare the graft copolymer.

An activator may be used to promote the initiation reaction of the peroxide together with the initiator, and the activator may be sodium formaldehyde sulfoxylate, sodium ethylenediamine tetraacetate, ferrous sulfate, dextrose, sodium pyrrolate or arbor. Sodium sulfate or the like may be used alone or in combination of two or more thereof. It is preferable to use 0.001 to 0.02 parts by weight of sodium formaldehyde, 0.001 to 0.02 parts by weight of sodium ethylenediamine tetraacetate and 0.0001 to 0.002 parts by weight of ferrous sulfate.

The ASA graft copolymer of the present invention preferably has a pH of 8 to 11, more preferably 9 to 10.5.

The particle size of the graft copolymer is measured using Nicomp 370 HPL by Dynamic Laser Light Scattering.

The graft copolymer can obtain a latex that is stable even when the total solid content is 35% by weight or more.

The graft copolymer is aggregated, aged, dehydrated and washed to produce graft copolymer powder.

Powder manufacturing method of the graft copolymer is agglomerated with a well-known coagulant sulfuric acid, MgSO ₄ , CaCl ₂ , Al ₂ (SO ₄ ) ₃ and the like, preferably agglomerated with CaCl ₂ . After atmospheric coagulation at 80 ° C. using an aqueous calcium chloride solution, the mixture was aged at 95 ° C., dehydrated and washed, and dried for 30 minutes with hot air at 90 ° C. to obtain powder particles of the graft copolymer.

The thermoplastic resin composition of the present invention comprises 30 to 70 parts by weight of the graft copolymer powder obtained above and 30 to 70 parts by weight of the SAN resin.

The thermoplastic resin composition may further include a lubricant, an antioxidant, a UV stabilizer, and other additives that are commonly used according to a use.

The SAN resin is a hard matrix capable of melt kneading with the graft copolymer, and is made of a hard polymer having a glass transition temperature of at least 60 ° C., and contains units derived from aromatic vinyl compounds, vinyl cyan compounds, methyl methacrylate, and the like. It is preferable to use the compound or the compound which can form a polycarbonate polymer, etc. individually or in mixture of 2 or more types.

Hereinafter, preferred examples are provided to help understanding of the present invention, but the following examples are merely to illustrate the present invention, and the scope of the present invention is not limited to the following examples.

EXAMPLE

Example 1

(1) Graft Copolymer Preparation

(a) hard polymer seed preparation

10 parts by weight of styrene, 0.15 parts by weight of NaHCO ₃ , 2 parts by weight of potassium rosin salt, ethylene glycol dimethacrylate, based on 100 parts by weight of the total monomers used to prepare the graft copolymer in a nitrogen-substituted polymerization reactor (autoclave) 0.05 parts by weight, 0.025 parts by weight of aryl methacrylate and 60 parts by weight of distilled water were collectively administered, and the temperature was raised to 70 ° C, followed by the addition of 0.05 parts by weight of potassium persulfate to initiate the reaction. After reacting for 1 hour while maintaining at 70 ℃ to prepare a seed latex. The average particle diameter of the polymerized seed latex was 58 nm.

(b) Alkyl acrylate core preparation

In the presence of the seed latex, 40 parts by weight of butyl acrylate, 0.15 parts by weight of NaHCO ₃ , 0.5 parts by weight of potassium rosin acid salt and 0.5 parts by weight of potassium oleate salt, 0.3 parts by weight of ethylene glycol dimethacrylate, aryl methacrylate 0.15 A mixture of parts by weight, 40 parts by weight of distilled water and 0.05 parts by weight of potassium persulfate was continuously added at 70 ° C. for 3 hours, and further polymerized for 1 hour after the end of the charge to prepare a core latex. The average particle diameter of the polymerized core latex was 103 nm.

(c) acrylate rubber polymer preparation

After cooling the prepared core latex to 30 ℃, after adjusting the stirring speed of the stirrer to 10 rpm, 2.3 parts by weight of 7% acetic acid aqueous solution was slowly added for 1 hour, the stirring was stopped and left for 30 minutes to acryl Laterate rubber polymer latex was prepared. The average particle diameter of the prepared acrylate rubber polymer latex was 352 nm.

(d) graft shell manufacturing

37.5 parts by weight of styrene, 12.5 parts by weight of acrylonitrile, rosin acid in the presence of 50 parts by weight (based on solids) of the acrylate rubber polymer latex subjected to the acidification-extension process based on 100 parts by weight of the total monomers used to prepare the graft copolymer. The polymerization reaction was carried out while continuously adding a mixture of 1.5 parts by weight of potassium, 0.05 parts by weight of potassium persulfate, 0.1 parts by weight of tertiary dodecyl mercaptan and 60 parts by weight of distilled water at 70 ° C. for 4 hours. In addition, in order to increase the polymerization conversion rate, the temperature was raised to 78 ° C. after completion of the reaction, and further reacted for 1 hour and cooled to 60 ° C. The total solids content in the final graft copolymer latex obtained after completion of the reaction was 35%. The polymerization conversion rate of the obtained graft copolymer latex was 99.5%, and the average particle diameter was 436 nm.

(2) Graft Copolymer Powder Preparation

The obtained graft copolymer latex was subjected to atmospheric aggregation at 80 ° C. using CaCl ₂ aqueous solution, then aged at 95 ° C., dehydrated and washed, and dried for 30 minutes by hot air at 90 ° C. to obtain graft copolymer powder. The particles were obtained.

(3) Manufacture of thermoplastic resin composition

45 parts by weight of the graft copolymer powder obtained above and 55 parts by weight of a SAN copolymer (LG Chemical, product name: 90HR) were added to 1 part by weight of a lubricant, 0.5 part by weight of an antioxidant, and 0.5 part by weight of a UV stabilizer. The mixture was prepared in pellet form using a 40 pie extrusion kneader at a cylinder temperature of 220 ° C., and injected into the pellet to prepare a physical specimen. Izod impact strength, tensile strength, gloss was measured as follows.

In addition, 45 parts by weight of the graft copolymer powder obtained above and 55 parts by weight of the SAN copolymer (LG Chemical, product name: 90HR) in a hard matrix, 1 part by weight of lubricant, 0.5 part by weight of antioxidant, 0.5 part by weight of UV stabilizer, 1 part by weight of carbon black was added and mixed. This was prepared in pellet form using a 40 pie extrusion kneader at a cylinder temperature of 220 ° C., and injected into the pellet to prepare a pigment colorimetric test specimen, and measured pigment colorability as follows.

Example 2

In Example 1, the same composition and method as in Example 1 were performed except that 8 parts by weight of styrene and 2 parts by weight of methyl methacrylate were used during the seed polymerization of (a).

Example 3

Seed latex was prepared in the same composition and method as in Example 1 (a), except that 20 parts by weight of styrene and 4 parts by weight of rosin acid potassium salt were used in the seed polymerization of (a). The average particle diameter of was 60 nm.

Except for using 30 parts by weight of butyl acrylate when preparing the core of (b) was carried out in the same composition and method as in (b) of Example 1, the average particle diameter of the prepared core latex was 82 nm.

Except for applying 2.8 parts by weight of a 7% acetic acid aqueous solution when preparing the acrylate rubber polymer of (c), the same composition and method as in Example (c) of Example 1, the average particle diameter of the prepared acrylate latex 349 nm.

The average particle diameter of the final graft copolymer latex prepared by the above method was 425 nm.

The same composition and method as in Example 1, except that 60 parts by weight of graft copolymer powder and 40 parts by weight of SAN copolymer (LG Chemical, product name: 90HR) are used as a hard matrix. Was carried out.

Comparative Example 1

In Example 1, 10 parts by weight of butyl acrylate is used as a monomer during the seed polymerization of (a), and 36 parts by weight of the graft copolymer powder in Example 3 (3), and a SAN copolymer (LG chemical) as a hard matrix. Product, product name: 90 HR) The same composition and method as in Example 1 were conducted except that 64 parts by weight were used.

Comparative Example 2

In Example 1, except that 0.6 parts by weight of potassium rosin salt was used in the seed polymerization of (a), the same composition and method as in (a) of Example 1 were carried out, and the average particle diameter of the prepared seed latex was 176. nm.

The average particle diameter of the core latex prepared using the seed latex was 347 nm.

The core latex was carried out in the same composition and method as in Example 1 except that the acid latex process was not performed.

Comparative Example 3

The final graft copolymer latex prepared in Example 1 was subjected to the same composition and method as in Example 1 except that the average particle diameter of the final graft copolymer latex was 129 nm.

Comparative Example 4

The average particle diameter of the acrylate rubber polymer latex prepared by using 1.4 parts by weight of 7% acetic acid aqueous solution in Example 1 (c) is 230 nm, the average particle diameter of the final graft copolymer latex prepared in the presence of the rubber latex Silver was carried out in the same composition and method as Example 1 except that it was 293 nm.

Physical properties of the specimens prepared according to the Examples and Comparative Examples were measured by the following methods, and the results are shown in Table 1 below.

A) Izod impact strength (1/4 "notched at 23 ° C., kg · cm / cm) —measured according to ASTM D256 method.

B) Pigment coloring property-The L value of the coloring test piece was measured using a color system. The lower the L value, the lower the brightness is, the darker black color means that the pigment colorability is good.

C) Tensile strength (50 mm / min, kg / cm 2)-measured according to ASTM D638.

D) fluidity (220 ° C./10 Kg, g / 10 min) —measured according to ASTM D1238.

광택) gloss (45 ° angle) —measured according to ASTM D528.

Iii) Thermal Stability-After pelleting pellets prepared using an extrusion kneader in an injection molding machine having a molding temperature of 260 ° C. for 5 minutes, the molded specimens exhibited a degree of discoloration as shown in Equation 1 below, wherein? It is the arithmetic mean value of the Hunter Lab values before and after, and the closer to 0, the better the retention thermal stability.

division Example 1 Example 2 Example 3 Comparative Example 1 Comparative Example 2 Comparative Example 3 Comparative Example 4 Impact strength 22 20 19 23 17 2 8 Pigmentation 17.9 17.8 17.6 22.5 19.3 16.6 17.3 The tensile strength 480 478 485 467 475 532 513 liquidity 13 13 14 13 13 16 15 Polish 95 95 96 85 94 98 96 Thermal Stability (△ E) 3.2 3.7 3.4 3.8 3.6 5.4 4.3

Through the Table 1, the graft air comprising a graft shell prepared in the presence of the rubber polymer to form a rubber polymer, the alkyl acrylate core latex comprising a hard polymer seed in accordance with the present invention through an acid-enlarging process The ASA thermoplastic resin composition prepared by mixing the copolymer and the SAN resin was excellent in impact strength, tensile strength, fluidity, gloss and thermal stability, and at the same time, it was confirmed that the pigment coloring property was much superior to the conventional ASA thermoplastic resin composition. .

As described above, the ASA graft copolymer prepared according to the present invention is not only excellent in basic physical properties and thermal stability, such as impact strength, tensile strength, flowability, gloss, mixed with SAN resin, but also excellent in pigment coloring. There is an effect of providing a thermoplastic resin composition.

Although described in detail above with reference to the described embodiments of the present invention, it will be apparent to those skilled in the art that various changes and modifications can be made within the scope and spirit of the present invention, and such variations and modifications belong to the appended claims. It is also natural.

Claims (10)

(a) preparing a hard polymer seed; (b) preparing an alkyl acrylate core in the presence of the hard polymer seed of (a); (c) preparing an acrylate rubber polymer by acid-enlarging the core of (b); And (d) preparing a graft shell in the presence of the acrylate rubber polymer of (c); Method for producing an acrylate-styrene-acrylonitrile graft copolymer comprising a. The method of claim 1, The acrylate-styrene-acrylonitrile graft copolymer 5 to 25 parts by weight of monomers selected from the group consisting of aromatic vinyl compounds, vinyl cyan compounds and methyl methacrylate, 0.05 to 0.3 parts by weight of electrolyte, 0.01 to 0.5 parts by weight of crosslinking agent and 0.01 to 0.5 parts by weight of grafting agent, and Hard polymer seeds prepared by polymerizing 0.05 to 4 parts by weight of the surfactant; Alkyl prepared by polymerizing 20 to 70 parts by weight of alkyl acrylate, 0.05 to 0.3 part by weight of electrolyte, 0.1 to 1 part by weight of crosslinking agent, 0.05 to 0.5 part by weight of grafting agent and 0.05 to 4 parts by weight of surfactant in the presence of the hard polymer seed Acrylate cores; An acrylate rubber polymer prepared through an acid-enlarging process of the alkyl acrylate core; And A graft shell prepared by polymerizing 10 to 50 parts by weight of aromatic vinyl compound, 5 to 25 parts by weight of vinyl cyan compound, and 0.05 to 4 parts by weight of surfactant in the presence of the acrylate rubber polymer; Method for producing an acrylate-styrene-acrylonitrile graft copolymer comprising a. The method of claim 1, The acrylate rubber polymer having an average particle diameter of 200 to 500 nm prepared by an acid-enlarging process of the alkyl acrylate core having an average particle size of 80 to 250 nm including the hard polymer seed having the average particle size of 50 to 100 nm Method for producing an acrylate-styrene-acrylonitrile graft copolymer, characterized in that used. The method of claim 2, The aromatic vinyl compound is an acrylate-styrene-acrylonitrile graft copolymer, characterized in that styrene, α-methylstyrene, p-methylstyrene vinyltoluene, and substituents thereof are used alone or in combination. Manufacturing method. The method of claim 2, The vinyl cyan compound is a method for producing an acrylate-styrene-acrylonitrile graft copolymer, characterized in that acrylonitrile, methacrylonitrile, ethacrylonitrile or the like is used alone or in combination of two or more thereof. The method of claim 2, The alkyl acrylate is a method of producing an acrylate-styrene-acrylonitrile graft copolymer, characterized in that using butyl acrylate or ethyl hexyl acrylate. The method according to claim 1 to 6, The acrylate-styrene-acrylonitrile graft copolymer prepared by the above method has a pH of 8 to 11 and a gel content of 50 to 95%. Manufacturing method. An acrylate-styrene-acrylonitrile graft copolymer powder prepared by coagulation, aging, dehydration and washing of the acrylate-styrene-acrylonitrile graft copolymer prepared in claims 1 to 6. An acrylate-styrene-acrylonitrile thermoplastic resin composition comprising the acrylate-styrene-acrylonitrile graft copolymer powder of claim 8 and a styrene-acrylonitrile resin. The method of claim 9, The acrylate-styrene-acrylonitrile thermoplastic resin composition comprises 30 to 70 parts by weight of the acrylate-styrene-acrylonitrile graft copolymer powder and 30 to 70 parts by weight of styrene-acrylonitrile resin. Acrylate-styrene-acrylonitrile thermoplastic resin composition.