KR102331303B1 - Diene based rubber latex, method for preparing thereof and core-shell structured graft copolymer comprising the same - Google Patents

Abstract

The present invention relates to a super-diameter diene-based rubber latex containing a polymer aggregate, a method for producing the same, and a graft copolymer having a core-shell structure comprising the same and having excellent impact strength and surface properties, wherein 100% by weight of the total rubber particles Based on 14 wt% to 26 wt% represents a particle diameter of 100 nm or more and less than 300 nm, 62 wt% to 81 wt% represents a particle diameter of 300 nm or more and less than 800 nm, 5 wt% to 14 wt% represents a particle diameter of 800 nm It provides a diene-based rubber latex having a particle diameter of more than 1000 nm.

Description

Diene-based rubber latex, manufacturing method thereof, and core-shell structured graft copolymer comprising the same

The present invention relates to a super-diameter diene-based rubber latex containing a polymer aggregate, a method for preparing the same, and a core-shell graft copolymer having excellent impact strength and surface properties including the same.

In general, acrylonitrile-butadiene-styrene-based graft resins (hereinafter referred to as ABS graft resins) have relatively good physical properties such as impact resistance, mechanical strength, moldability, and gloss, and thus electrical, electronic parts, office equipment, and automobile parts. It is widely used, etc.

ABS graft resins are generally prepared through emulsion graft polymerization, and after preparing large-diameter diene-based rubber latex or small-diameter diene-based rubber latex by emulsion polymerization to impart impact strength, an aromatic vinyl compound And a vinyl cyan compound is added to the graft reaction by emulsion graft polymerization to prepare an acrylonitrile-butadiene-styrene-based graft copolymer, and the styrene-acrylonitrile copolymer (hereinafter, SAN ) to finally produce a thermoplastic ABS-based resin.

However, when a large-diameter diene-based rubber latex is used, there is a limitation in improving the surface gloss and there is a problem that the impact strength is severely lowered. and small-diameter diene-based rubber latex was proposed, but both impact strength and surface gloss did not show sufficiently improved effects, and there was a problem in that physical properties vary greatly depending on injection conditions.

In order to solve this problem, after polymerizing the ABS graft resin with two kinds of diene-based rubber latex having different average particle diameters, a diene-based rubber latex having a larger average particle diameter than the two kinds of diene-based rubber latex is used in the resin. A method of mixing during extrusion or mixing three types of diene-based rubber latex having different average particle diameters during extrusion of the resin has been proposed, however, since each diene-based rubber latex must be prepared separately, economical and time loss are large.

In addition, in general, a large-diameter diene-based rubber latex is prepared by 1) a polymerization method using an acid or alkali, 2) a polymerization method in which the amount of inorganic electrolyte is increased or the amount of an emulsifier is greatly reduced, 3) a latex is prepared and its temperature is lowered. It is manufactured using a method of agglomeration, 4) mechanical and chemical agglomeration after latex manufacturing, and the like. There is a problem that productivity decreases because it has to go through the process.

Therefore, there is a need for a method capable of obtaining economical and productive advantages while improving the impact strength and surface gloss in a balanced way without degrading other physical properties of the ABS graft resin.

JP 1994-032961 A

The present invention has been devised to solve the problems of the prior art, and an object of the present invention is to provide a diene-based rubber latex having excellent latex stability with a small amount of solid coagulation.

In addition, an object of the present invention is to provide a method for producing the diene-based rubber latex using an in situ method.

In addition, an object of the present invention is to provide a graft copolymer having a core-shell structure having excellent impact strength and surface gloss, including the diene-based rubber latex.

In order to solve the above problems, the present invention, based on 100% by weight of the total rubber particles, 14% to 26% by weight represents a particle size of 100 nm or more and less than 300 nm, 62% to 81% by weight is 300 nm or more It provides a diene-based rubber latex having a particle diameter of less than 800 nm, and 5 wt% to 14 wt% exhibiting a particle diameter of 800 nm or more and less than 1000 nm.

In addition, the present invention comprises the steps of preparing a primary polymer having a polymerization conversion of 30% to 40% by primary polymerization of a first conjugated diene-based monomer in the presence of an emulsifier and a fat-soluble polymerization initiator (step a); preparing a secondary polymer having a polymerization conversion of 60% to 70% by adding a water-soluble polymerization initiator to the first polymer and increasing the temperature (step b); preparing a tertiary polymer having a polymerization conversion of 85% to 93% by adding a second conjugated diene-based monomer to the secondary polymer and performing tertiary polymerization (step c); and adding a polymer aggregate having an average particle diameter of 230 nm to 300 nm and a water-soluble polymerization initiator to the tertiary polymer and performing quaternary polymerization (step d), wherein the first conjugated diene-based monomer and the second conjugated diene-based monomer are added. The monomer is used in a weight ratio of 80 to 95:5 to 20, and the polymer aggregate is added in an amount of 0.01 parts by weight to 1.50 parts by weight based on 100 parts by weight of the total amount of the first conjugated diene-based monomer and the second conjugated diene-based monomer. Provided is a method for producing a diene-based rubber latex.

In addition, the present invention is a rubbery polymer core; and a shell surrounding the core and comprising an aromatic vinyl-based monomer-derived unit and a vinyl cyan-based monomer-derived unit, wherein the rubbery polymer core has an average particle diameter of 600 nm to 800 nm of diene-based rubber latex 3 parts by weight To 5 parts by weight and an average particle diameter of 310 nm to 330 nm diene-based rubber latex comprising 95 parts by weight to 97 parts by weight of a core-shell structure graft copolymer is provided.

The diene-based rubber latex according to the present invention has low solid coagulation content and excellent latex stability, and thus can effectively improve the impact strength and surface gloss of the core-shell structure graft copolymer containing the diene-based rubber latex.

The method for producing a diene-based rubber latex according to the present invention is economical by being prepared in an in situ method, and uses a polymer aggregate having an average particle diameter of 230 nm to 300 nm prepared in the presence of a crosslinking agent, and includes a monomer according to a polymerization conversion rate. Diene rubber latex having a small solid coagulation content and excellent latex stability and having a spherical particle shape can be prepared by performing multi-step polymerization by dividing the mixture.

In addition, the graft copolymer having a core-shell structure according to the present invention can improve impact strength and surface gloss while having excellent tensile strength and flow index by including the diene-based rubber latex.

Hereinafter, the present invention will be described in more detail to help the understanding of the present invention.

The terms or words used in the present specification and claims should not be construed as being limited to their ordinary or dictionary meanings, and the inventor may properly define the concept of the term in order to best describe his invention. It should be interpreted as meaning and concept consistent with the technical idea of the present invention based on the principle that there is.

In addition, the terms and measuring method used in the present invention may be defined as follows unless otherwise defined.

[Terms]

The term 'rubber latex' used in the present invention is a reaction product obtained by emulsion polymerization of a monomer, and may refer to an aqueous medium in which rubber particles are dispersed, for example, a diene-based rubber latex is a conjugated diene-based It may refer to a reaction product obtained by emulsion polymerization of a monomer including the monomer.

The term 'rubber' used in the present invention may refer to a polymer chain formed by polymerization of a monomer having rubbery elasticity.

The terms 'first conjugated diene-based monomer' and 'second conjugated diene-based monomer' used in the present invention refer to the same conjugated diene-based monomer, and the 'first' and 'second' refer to the input of the conjugated diene-based monomer. This is to differentiate the point of time.

The term 'polymer aggregate' used in the present invention refers to a state in which polymer chains are crosslinked and aggregated.

The term 'circularity' used in the present invention is an index indicating how close to the spherical shape of the particles in the latex, and can also be called spheroidicity, and for 50 particles in the latex, the long axis passing through the center of the particle Measuring the length and the length of the minor axis perpendicular to the major axis passing through the center of the particle, and obtaining the ratio of the length of the major axis to the length of the minor axis in each particle (length of the major axis/length of the minor axis), It was defined as the average value of the ratio of the length of the major axis to the length of the minor axis, and the closer the number is to 1, the closer the length of the major axis to the length of the minor axis of each particle. can do.

[How to measure]

In the present invention, 'average particle diameter (nm)' and 'weight % according to particle diameter' are measured using a CHDF device (Capillary Hydrodynamic Fractionation, Matec Applied Science, Model 1100) after diluting 1 g of rubber latex in 100 g of distilled water. did. Here, the CHDF device is a device that can measure the particle size and distribution through a time difference in which particles are eluted from the column using a capillary column filled with a porous or non-porous filler, and the sample to be measured was injected into the column to measure the elution time, and the elution time was measured by passing monodisperse particles of known particle size through the column for each size. Particle size distribution according to weight % can be measured.

In the present invention, 'solid content (% by weight)' refers to the ratio of solids in the reaction product to 100% by weight of the total weight of the reactants used in the reaction, and is used as a measure of the stability of the reaction product. The stability of the reaction product is evaluated to be high. Specifically, the solid coagulation component is a diene-based rubber latex or a core-shell structure graft copolymer is filtered through a 100 mesh wire mesh, and the reaction product that has not passed over the wire mesh is dried in a hot air dryer at 100° C. for 1 hour. To measure the weight of the coagulated product, it was calculated by Equation 2 below.

[Equation 2]

Solid coagulation content (wt%) = [Coagulant weight (g) / Total reactant weight (g)] × 100

In the present invention, 'polymerization conversion (%)' indicates the degree of conversion of the monomers inputted into the reaction to the polymer, and 1.5 g of the polymer is collected and dried in a hot air dryer at 150° C. for 15 minutes, then the weight is measured and the total solid content The content (TSC) was obtained and calculated by the following Equation 3 using this. Here, the polymer refers to all materials produced after the reaction product is introduced into the reactor and the reaction is started, and components and ratios constituting the polymer may be different depending on the time of collection.

[Equation 3]

Polymerization conversion (%) = [Total amount of monomers added (g) / Total solid content (g)] × 100

In the present invention, 'Izod impact strength (kgf · cm/cm)' was measured using a 1/4″ thick specimen, and using this, an impact strength measuring instrument (TINIUS OLSEN) according to ASTM D256.

In the present invention, 'surface gloss (Gloss)' was measured at a 45° angle with a gloss meter according to ASTM D528.

The present invention is applied to a copolymer of a vinyl cyanide-based monomer-conjugated diene-based monomer-aromatic vinyl-based monomer to improve surface gloss and impact strength without reducing other physical properties such as mechanical strength and moldability thereof, diene-based, Provides rubber latex.

The diene-based rubber latex according to an embodiment of the present invention is manufactured through an in situ method to be described later, and may be a trimodal rubber latex.

Specifically, the diene-based rubber latex is 14% to 26% by weight based on 100% by weight of the total rubber particles exhibiting a particle diameter of 100 nm or more and less than 300 nm, 62% to 81% by weight of 300 nm or more and 800 nm It exhibits a particle diameter of less than 5 wt% to 14 wt% is characterized in that it represents a particle diameter of 800 nm or more and less than 1000 nm.

In addition, the diene-based rubber latex according to an embodiment of the present invention may have a circularity defined by the following Equation 1 of 1.05 to 1.10.

[Equation 1]

In Equation 1, D _i is the ratio of the length of the major axis to the length of the minor axis in the i-th particle in the latex [length of the major axis/length of the minor axis].

In addition, the diene-based rubber latex according to an embodiment of the present invention includes a unit derived from an unsaturated carboxylic acid or an ester monomer thereof and a unit derived from a comonomer having a functional group, and an average particle diameter of 230 nm to 300 nm. It may be a hypertrophic, average particle diameter of 600 nm to 800 nm.

In general, for acrylonitrile-butadiene-styrene-based graft resins (hereinafter, ABS graft resins), rubber latex is added during manufacturing or molding of the resin in order to impart impact strength. However, in the case of using a large diameter rubber latex, although the impact strength is slightly increased, the surface gloss is rather greatly reduced. When large-diameter and small-diameter rubber latex are used together, the effect of improving impact strength and surface gloss is insignificant, and there is a problem of low reproducibility of physical properties because the properties expressed according to molding conditions are different.

However, the diene-based rubber latex according to the present invention is produced by an in situ manufacturing method described later using a polymer aggregate prepared in the presence of a crosslinking agent, so that some of the particles constituting the diene-based rubber latex are aggregated with the polymer aggregate. It is enlarged and may have a spherical particle shape while having super-diameter particle characteristics with an average particle diameter of 600 nm to 800 nm, and in addition, trimodal properties of super-diameter rubber particles, large-diameter rubber particles, and small-diameter rubber particles It is possible to effectively improve surface gloss and impact strength without adversely affecting other physical properties such as mechanical strength and moldability of a resin containing the latex, such as a core-cell structure graft copolymer.

Hereinafter, the diene-based rubber latex according to the present invention will be described in detail.

In one embodiment of the present invention, the diene-based rubber latex is a reaction product prepared by emulsion polymerization of a monomer containing a conjugated diene-based monomer by a manufacturing method described below, and a conjugated diene rubber containing only a unit derived from a conjugated diene-based monomer. It may be a latex or a two-component or more rubber latex comprising a unit derived from a conjugated diene-based monomer and a unit derived from a comonomer.

Specifically, the diene-based rubber latex may include at least one selected from the group consisting of butadiene rubber, isoprene rubber, chloroprene rubber, piperylene rubber, butadiene-styrene rubber, and butadiene-acrylonitrile rubber.

In addition, the diene-based rubber latex may be a super-diameter having an average particle diameter of 600 nm to 800 nm, and in this case, it is possible to greatly improve the surface gloss of the resin including the latex.

In addition, while the diene-based rubber latex has the above average particle diameter, 14% to 26% by weight based on 100% by weight of the total rubber particles as described above represents a particle diameter of 100 nm or more and less than 300 nm, 62 weight % to 81 wt% represents a particle diameter of 300 nm or more and less than 800 nm, and 5 wt% to 14 wt% represents a trimodal particle characteristic showing a particle diameter of 800 nm or more and less than 1000 nm, specifically, the entire rubber particle 100 Based on the weight %, 17 wt% to 21 wt% represents a particle diameter of 100 nm or more and less than 300 nm, 68 wt% to 71 wt% represents a particle diameter of 300 nm or more and less than 800 nm, and 8 wt% to 12 wt% may exhibit trimodal particle characteristics showing a particle diameter of 800 nm or more and less than 1000 nm, in this case, the surface gloss and impact strength can be improved without affecting the mechanical strength and moldability of the resin containing the latex. .

More specifically, the diene-based rubber latex according to an embodiment of the present invention is prepared by the in situ manufacturing method described later using a polymer aggregate in the last stage of polymerization, and among the rubber particles constituting the diene-based rubber latex, At least a portion of the polymer aggregate is agglomerated and enlarged, and thus the particles may have a uniform spherical shape while having the above trimodal particle characteristics and an average particle diameter within the above range.

Here, the polymer aggregate is to enlarge the rubber particles in the diene-based rubber latex, and by having an average particle diameter of 230 nm to 300 nm, the average particle diameter of the diene-based rubber latex can be easily induced into the super-diameter. .

In addition, the polymer aggregate may be more firmly crosslinked by the production method described later, that is, produced in the presence of a crosslinking agent, so that the diene-based latex particles enlarged from the polymer aggregate are spherical. It can be made to have a diene-based latex can include a solid coagulation content of 0.01 wt% or less, and as a result, the stability of the latex can be improved.

In addition, the polymer aggregate is an unsaturated carboxylic acid monomer-derived unit; or a polymer including the unsaturated carboxylic acid ester monomer-derived unit, or a copolymer comprising an unsaturated carboxylic acid monomer-derived unit and an unsaturated carboxylic acid ester monomer-derived unit; Or it may be a copolymer comprising a unit derived from an unsaturated carboxylic acid or an ester monomer thereof and a unit derived from a comonomer having a functional group, and specifically, the polymer aggregate contains 82 wt% to a unit derived from an unsaturated carboxylic acid or an ester monomer thereof. It may be a copolymer comprising 92 wt%, and 8 wt% to 18 wt% of a comonomer-derived unit having a functional group. In this case, it may be easy to enlarge the particles constituting the diene-based rubber latex including the same.

Here, the unsaturated carboxylic acid or its ester monomer is methyl methacrylate, ethyl methacrylate, butyl methacrylate, methyl acrylate, ethyl acrylate, acrylic acid, methacrylic acid, itaconic acid, maleic acid, fumaric acid, anhydrous It may be at least one member selected from the group consisting of maleic acid, monobutyl murafate, monobutyl maleate, and mono-2-hydroxypropyl maleate.

In addition, the comonomer having the functional group may be a material copolymerizable with the unsaturated carboxylic acid or its ester monomer and include the functional group, wherein the functional group is an amide group, an alcohol group, a carboxylic acid group, or a sulfonic acid. It may be at least one selected from the group consisting of a group, a phosphoric acid group and a boric acid group, and illustratively, the comonomer may be methacrylamide, acrylamide, or a combination thereof.

In addition, the present invention provides a method for producing the diene-based rubber latex.

The manufacturing method according to an embodiment of the present invention comprises the steps of primary polymerization of a first conjugated diene-based monomer in the presence of an emulsifier and a fat-soluble polymerization initiator to prepare a primary polymer having a polymerization conversion of 30% to 40% (step a); preparing a secondary polymer having a polymerization conversion of 60% to 70% by adding a water-soluble polymerization initiator to the first polymer and increasing the temperature (step b); preparing a tertiary polymer having a polymerization conversion of 85% to 93% by adding a second conjugated diene-based monomer to the secondary polymer and performing tertiary polymerization (step c); and adding a polymer aggregate having an average particle diameter of 230 nm to 300 nm and a water-soluble polymerization initiator to the tertiary polymer and performing quaternary polymerization (step d), wherein the first conjugated diene-based monomer and the second conjugated diene-based monomer are added. The monomer is used in a weight ratio of 80 to 95:5 to 20, and the polymer aggregate is added in an amount of 0.01 parts by weight to 1.50 parts by weight based on 100 parts by weight of the total amount of the first conjugated diene-based monomer and the second conjugated diene-based monomer. do.

The step a is a step for preparing a primary polymer having a polymerization conversion rate of 30% to 40% by polymerizing the first conjugated diene-based monomer, and the first conjugated diene-based monomer is first polymerized in the presence of an emulsifier and a fat-soluble polymerization initiator. it may be performing

In addition, if necessary in the primary polymerization, a comonomer copolymerizable with the first conjugated diene-based monomer may be polymerized together with the first conjugated diene-based monomer, and the comonomer is, for example, an aromatic vinyl-based monomer or a vinyl cyan-based monomer. monomers or combinations thereof. If, when polymerizing the comonomer together, the comonomer may be used in an amount of 20 parts by weight or less based on 100 parts by weight of a total of monomers used in the preparation method.

The first conjugated diene-based monomer may be the same as the second conjugated diene-based monomer to be described later, and specifically may be at least one selected from the group consisting of 1,3-butadiene, isoprene, chloroprene and piperylene.

In addition, the aromatic vinyl-based monomer may be selected from styrene, α-methylstyrene, α-ethylstyrene, p-methylstyrene, o-methylstyrene, ot-butylstyrene, bromostyrene, chlorostyrene, trichlorostyrene and derivatives thereof. It may be one or more selected from the group consisting of, and the vinyl cyan-based monomer may be one or more selected from the group consisting of acrylonitrile, methacrylonitrile, ethacrylonitrile and derivatives thereof, wherein the derivative is One or more of the hydrogen atoms constituting the original compound may represent a compound having a structure in which one or more hydrogen atoms are substituted with a halogen group, an alkyl group, or a hydroxyl group.

The emulsifier is not particularly limited, but may be used in an amount of 1.0 to 5.0 parts by weight, specifically 1.0 to 3.0 parts by weight, based on 100 parts by weight of the total monomers used in the preparation method.

In addition, the emulsifier is not particularly limited, but for example, an anionic adsorption type emulsifier such as alkali rosin acid salt, fatty acid saponified product, sodium lauryl sulfonate, sodium alkylbenzene sulfonate, and nonionic polyoxyethylene alkylphenyl ether. Reactive emulsifiers such as dioctyl sodium sulfosuccinate, sodium dodecyl allyl sulfosuccinate, C _16-18 alkenyl succinic acid di-potassium salt, sodium acrylamidostearate, polyoxyethylene alkylphenyl Polymeric reactive emulsifiers such as ether ammonium sulfate and polyoxyethylene alkyl ether sulfate ester ammonium salt may be used alone or in combination.

In addition, the fat-soluble polymerization initiator is not particularly limited, but may be used in an amount of 0.1 parts by weight to 0.5 parts by weight, specifically 0.1 parts by weight to 0.3 parts by weight, based on 100 parts by weight of the total monomers used in the preparation method, and cumene hydroperoxide , diisopropyl benzene hydroperoxide, azobis isobutyronitrile, tertiary butyl hydroperoxide, paramethane hydroperoxide and at least one from the group consisting of benzoyl peroxide may be used.

In addition, the primary polymerization may additionally use an electrolyte, a molecular weight regulator, and an oxidation-reduction catalyst, if necessary.

The electrolyte is not particularly limited, but for example, potassium chloride, sodium chloride, potassium bicarbonate, sodium carbonate, potassium carbonate, potassium hydrogen sulfite, monosodium hydrosulfite tetrapotassium pyrophosphate, tetrasodium pyrophosphate, tripotassium phosphate, trisodium phosphate, dipotassium hydrogen phosphate And it may be at least one selected from the group consisting of disodium hydrogen phosphate, and may be used in an amount of 0.2 to 2 parts by weight based on 100 parts by weight of the total monomer.

The molecular weight modifier is not particularly limited, but commonly known types such as mercaptans may be used, for example, tertiary dodecyl mercaptan may be used, and 0.2 to 0.6 parts by weight based on 100 parts by weight of the total monomer. Can be used.

In addition, the oxidation-reduction catalyst serves as an additional polymerization initiator and is not particularly limited, for example, sodium formaldehyde, sulfoxylate, sodium ethylene diamine tetraacetate, ferrous sulfate, dextrose, sodium pyrophosphate and At least one selected from the group consisting of sodium sulfite may be used, and may be used in an amount of 0.001 parts by weight to 0.1 parts by weight based on 100 parts by weight of the total monomer.

The step b is a step for preparing a secondary polymer having a polymerization conversion of 60% to 70% by continuously polymerizing the primary polymer. Secondary polymerization may be performed by adding a water-soluble polymerization initiator to the primary polymer and increasing the temperature. . Here, the temperature increase may be to increase the temperature to 15° C. to 25° C. higher than the temperature during the primary polymerization, and thus the secondary polymerization may be performed at a temperature 15° C. to 25° C. higher than the primary polymerization.

The water-soluble polymerization initiator is not particularly limited, but may be used in an amount of 0.1 parts by weight to 0.5 parts by weight, specifically 0.1 parts by weight to 0.3 parts by weight, based on 100 parts by weight of a total of monomers used in the preparation method, potassium persulfate, sodium persulfate and at least one selected from the group consisting of ammonium persulfate may be used.

Step c is a step for preparing a tertiary polymer having a polymerization conversion of 85% to 93% from the secondary polymer, and may be performed by introducing a second conjugated diene-based monomer to the secondary polymer and performing tertiary polymerization.

On the other hand, in the manufacturing method according to an embodiment of the present invention, the weight ratio of the first conjugated diene-based monomer and the second conjugated diene-based monomer is 80 to 95:5 to 20, specifically, 85 to 90:10 to 15. It may be used as a weight ratio.

In addition, the step d is a step for preparing a diene-based rubber latex from the tertiary polymer, and a polymer aggregate having an average particle diameter of 230 nm to 300 nm and a water-soluble polymerization initiator are added to the tertiary polymer, followed by quaternary polymerization. it could be In this case, the polymer aggregate may be used in an amount of 0.01 parts by weight to 1.50 parts by weight based on 100 parts by weight of the total monomers used for polymerization, that is, 100 parts by weight of the total amount of the first conjugated diene-based monomer and the second conjugated diene-based monomer. In this case, the rubber particles in the diene-based rubber latex may be agglomerated with the polymer aggregate in an appropriate ratio to be enlarged, and as a result, a diene-based rubber latex having an average particle diameter and trimodal characteristics as described above may be prepared.

The water-soluble polymerization initiator in step d is not particularly limited, but may be used in an amount of 0.05 parts by weight to 0.2 parts by weight based on 100 parts by weight of a total of monomers used in the preparation method, and specific materials are the same as described above.

In addition, the polymer aggregate may be prepared by emulsion polymerization comprising the following steps:

i) polymerizing 20 parts by weight to 40 parts by weight of an unsaturated carboxylic acid or an ester monomer thereof in the presence of 0.1 parts by weight to 0.2 parts by weight of a crosslinking agent; and

ii) at a time when the polymerization conversion rate of step i) is 85% to 95% step.

Meanwhile, parts by weight of the material used in the preparation of the polymer aggregate are expressed based on 100 parts by weight of the total amount of the unsaturated carboxylic acid or its ester monomer and the comonomer having a functional group.

The step i) is a step for preparing a prepolymer capable of serving as a seed by polymerizing an unsaturated carboxylic acid or an ester monomer thereof, and an unsaturated carboxylic acid or an ester monomer thereof 20 in the presence of 0.1 to 0.2 parts by weight of a crosslinking agent. It may be carried out by polymerizing 40 parts by weight to 40 parts by weight.

The crosslinking agent is introduced into the core portion of the polymer aggregate when the polymer aggregate is prepared and serves to assist in more easily crosslinking between the polymer chains constituting the polymer aggregate, for example, a polymer chain formed by an unsaturated carboxylic acid or an ester monomer thereof. This can be induced to form a stronger bond, and the bond between the monomer and the polymer chain to be added can be made more easily. That is, the polymer chain in the polymer aggregate may be more firmly crosslinked by the crosslinking agent, and thus the particles of the diene-based latex including the polymer aggregate may have a uniform spherical shape, so that the latex stability may be excellent, As a result, the surface gloss of the core-cell structure graft copolymer including the diene-based latex may be further improved. In addition, the crosslinking agent is ethylene glycol dimethacrylate, diethylene glycol dimethacrylate, triethylene glycol dimethacrylate, 1,3-butylene glycol dimethacrylate, aryl methacrylate and 1,3-butyl One or more selected from the group consisting of renglycol diacrylate may be used.

In addition, in step i), an emulsifier, a polymerization initiator, and a molecular weight regulator may be further used, wherein the emulsifier is 0.05 to 0.06 parts by weight, the polymerization initiator is 0.1 to 0.5 parts by weight, and the molecular weight regulator is 0.1 to 0.3 parts by weight. may be using In addition, specific materials of the emulsifier and the molecular weight modifier are the same as described above, and the polymerization initiator may include the aforementioned oil-soluble polymerization initiator and water-soluble polymerization initiator, and specifically may be the same as the water-soluble polymerization initiator.

Step ii) is a step for preparing a polymer aggregate from the prepolymer formed in step i). At the time when the polymerization conversion of step i) is 85% to 95%, 50 parts by weight of an unsaturated carboxylic acid or an ester monomer thereof to It may be carried out by adding 75 parts by weight and 5 to 10 parts by weight of a comonomer having a functional group and polymerization, wherein the unsaturated carboxylic acid or its ester monomer and a comonomer having a functional group are each added, or both It may be to prepare and input a mixture of

In addition, the point in time when the polymerization conversion rate of step i) is 85% to 95% may indicate that the polymerization conversion rate of the prepolymer is 85% to 95%.

In addition, in step ii), an emulsifier and a polymerization initiator may be used, and in this case, 0.05 to 0.06 parts by weight of the emulsifier and 0.5 to 2.0 parts by weight of the polymerization initiator may be used, and the specific material is step i) as described in

In addition, step i) may be performed at a temperature range of 60°C to 80°C, and step ii) may be performed at the same temperature as step i).

The polymer aggregate according to an embodiment of the present invention may have an average particle diameter of 230 nm to 300 nm by being prepared by the above manufacturing method in the presence of a crosslinking agent, and the polymer chains in the polymer aggregate may be more firmly crosslinked, including this Since the rubber particles of the diene-based rubber latex may have a regular spherical shape while having an average particle diameter of a super-diameter, latex stability may be excellent.

On the other hand, in step d, an emulsifier may be further used if necessary, and in this case, the emulsifier may be used in an amount of 0.1 to 0.5 parts by weight based on 100 parts by weight of the total monomer, and the specific materials are the same as described above.

In addition, in the method for producing a diene-based rubber latex according to the present invention, primary polymerization, tertiary polymerization, and quaternary polymerization excluding secondary polymerization may be performed under temperature conditions appropriately controlled according to the purpose, for example, primary polymerization, The tertiary polymerization and the quaternary polymerization may be performed under the same or different temperature conditions, and specifically, the tertiary polymerization and the quaternary polymerization may be performed under elevated temperature conditions compared to the primary polymerization. More specifically, the secondary polymerization may be performed at an elevated temperature condition of 15° C. to 25° C. compared to the primary polymerization, and the tertiary polymerization and the quaternary polymerization may be performed under the same temperature conditions as the secondary polymerization. In this case, the first polymerization may be performed at a temperature condition of 40°C to 70°C, and the secondary polymerization, tertiary polymerization and quaternary polymerization may be performed at a temperature condition of 70°C to 85°C. That is, the secondary polymerization may be performed at a temperature ranging from 70° C. to 85° C., but at an elevated temperature of 15° C. to 25° C. compared to the primary polymerization.

The manufacturing method according to the present invention uses a polymer aggregate having an average particle diameter of 230 nm to 300 nm prepared in the presence of a crosslinking agent, and divides the reactants including monomers according to the polymerization conversion rate to perform multi-step polymerization. It is possible to produce diene-based rubber latex having a small amount and excellent latex stability and uniform particle shape.

In addition, the present invention provides a graft copolymer having a core-shell structure comprising the diene-based rubber latex.

The copolymer according to an embodiment of the present invention includes a rubbery polymer core; and a shell surrounding the core and including an aromatic vinyl-based monomer-derived unit and a vinyl cyan-based monomer-derived unit, wherein the rubbery polymer core is a diene-based rubber latex having an average particle diameter of 600 nm to 800 nm. It is characterized in that it contains 95 parts by weight to 97 parts by weight of diene-based rubber latex having an average particle diameter of 310 nm to 330 nm and 5 parts by weight to 5 parts by weight.

Specifically, the copolymer comprises 40% to 60% by weight of the core; and 40% to 60% by weight of the shell, and the shell may include an aromatic vinyl-based monomer-derived unit and a vinylcyanic-based monomer-derived unit in a weight ratio of 3:1 to 2:1, in which case the air The composite may have better impact resistance, mechanical properties and moldability.

On the other hand, the copolymer according to an embodiment of the present invention may be prepared by adding a vinyl cyan-based monomer and an aromatic vinyl-based monomer to the rubbery polymer core containing the diene-based rubber latex and emulsion-graft polymerization, By including the diene-based rubber latex, the surface gloss and impact strength may be excellent while having excellent impact resistance, mechanical properties and moldability.

Specifically, the copolymer may have a solid content of 0.03% by weight or less.

Hereinafter, the present invention will be described in more detail by way of Examples and Experimental Examples. However, the following Examples and Experimental Examples are intended to illustrate the present invention, and the scope of the present invention is not limited thereto.

Preparation of polymer aggregates

Preparation Example 1

62 parts by weight of ion-exchanged water, 0.06 parts by weight of dioctyl sodium sulfosuccinate, 30 parts by weight of ethyl acrylate, 1 part by weight of methacrylic acid, 0.15 parts by weight of ethylene glycol dimethacrylate in a nitrogen-substituted polymerization reactor (autoclave) Parts, 0.15 parts by weight of tertiary dodecyl mercaptan (TDDM), and 0.3 parts by weight of potassium persulfate were batch-injected, and emulsion polymerization was carried out at 70°C. During polymerization, when the polymerization conversion rate reached 90%, 62 parts by weight of butyl acrylate, 7 parts by weight of methacrylamide, and 0.3 parts by weight of tertiary dodecyl mercaptan were mixed and added at a constant rate for 4 hours, and at the same time separated therefrom. 1.3 parts by weight of potassium persulfate and 0.06 parts by weight of dioctyl sodium sulfosuccinate were added at a constant rate for 5 hours, followed by emulsion polymerization at 70°C. When the polymerization conversion rate reached 99% or more, the polymerization was terminated to prepare a polymer aggregate having an average particle diameter of 251 nm.

Preparation 2

62 parts by weight of ion-exchanged water, 0.05 parts by weight of dioctyl sodium sulfosuccinate, 30 parts by weight of ethyl acrylate, 1 part by weight of methacrylic acid, 0.15 parts by weight of ethylene glycol dimethacrylate in a nitrogen-substituted polymerization reactor (autoclave) Parts, 0.15 parts by weight of tertiary dodecyl mercaptan (TDDM), and 0.3 parts by weight of potassium persulfate were batch-injected, and emulsion polymerization was carried out at 70°C. During polymerization, when the polymerization conversion rate reached 90%, 62 parts by weight of butyl acrylate, 7 parts by weight of methacrylamide, and 0.3 parts by weight of tertiary dodecyl mercaptan were mixed and added at a constant rate for 4 hours, and at the same time separated therefrom. 1.3 parts by weight of potassium persulfate and 0.06 parts by weight of dioctyl sodium sulfosuccinate were added at a constant rate for 5 hours, followed by emulsion polymerization at 70°C. When the polymerization conversion reached 99% or more, the polymerization was terminated to prepare a polymer aggregate having an average particle diameter of 280 nm.

Comparative Preparation Example 1

62 parts by weight of ion-exchanged water, 0.08 parts by weight of dioctyl sodium sulfosuccinate, 30 parts by weight of ethyl acrylate, 1 part by weight of methacrylic acid, 0.15 parts by weight of ethylene glycol dimethacrylate in a nitrogen-substituted polymerization reactor (autoclave) Parts, 0.15 parts by weight of tertiary dodecyl mercaptan (TDDM), and 0.3 parts by weight of potassium persulfate were batch-injected, and emulsion polymerization was carried out at 70°C. During polymerization, when the polymerization conversion rate reached 90%, 62 parts by weight of butyl acrylate, 7 parts by weight of methacrylamide, and 0.3 parts by weight of tertiary dodecyl mercaptan were mixed and added at a constant rate for 4 hours, and at the same time separated therefrom. 1.3 parts by weight of potassium persulfate and 0.08 parts by weight of dioctyl sodium sulfosuccinate were added at a constant rate for 5 hours, followed by emulsion polymerization at 70°C. When the polymerization conversion rate was 99% or more, the polymerization was terminated to prepare a polymer aggregate having an average particle diameter of 211 nm.

Comparative Preparation Example 2

62 parts by weight of ion-exchanged water, 0.04 parts by weight of dioctyl sodium sulfosuccinate, 30 parts by weight of ethyl acrylate, 1 part by weight of methacrylic acid, 0.15 parts by weight of ethylene glycol dimethacrylate in a nitrogen-substituted polymerization reactor (autoclave) Parts, 0.15 parts by weight of tertiary dodecyl mercaptan (TDDM), and 0.3 parts by weight of potassium persulfate were batch-injected, and emulsion polymerization was carried out at 70°C. During polymerization, when the polymerization conversion rate reached 90%, 62 parts by weight of butyl acrylate, 7 parts by weight of methacrylamide, and 0.3 parts by weight of tertiary dodecyl mercaptan were mixed and added at a constant rate for 4 hours, and at the same time separated therefrom. 1.1 parts by weight of potassium persulfate and 0.05 parts by weight of dioctyl sodium sulfosuccinate were added at a constant rate for 5 hours, followed by emulsion polymerization at 70°C. When the polymerization conversion rate reached 99% or more, the polymerization was terminated to prepare a polymer aggregate having an average particle diameter of 327 nm.

Comparative Preparation Example 3

In Preparation Example 1, a polymer aggregate having an average particle diameter of 267 nm was prepared in the same manner as in Preparation Example 1, except that ethylene glycol dimethacrylate was not used.

Polybutadiene Rubber Latex Manufacturing

Example 1

Based on 100 parts by weight of 1,3-butadiene, 75 parts by weight of ion-exchanged water, 90 parts by weight of 1,3-butadiene, 3 parts by weight of a fatty acid saponified product, 0.1 parts by weight of potassium carbonate, 3 0.1 parts by weight of quaternary dodecyl mercaptan (TDDM), 0.15 parts by weight of tertiary butyl hydroperoxide, 0.06 parts by weight of dextrose, 0.005 parts by weight of sodium picoliate, and 0.0025 parts by weight of ferrous sulfate were administered in batches and at 55° C. A primary polymer having a polymerization conversion of 35% was prepared by polymerization, 0.3 parts by weight of potassium persulfate was added thereto, the temperature was raised to 72° C., and then polymerization was continued to prepare a secondary polymer having a polymerization conversion of 65%. Here, 10 parts by weight of 1,3-butadiene is added, polymerization is performed until the polymerization conversion is 90%, and 0.5 parts by weight of the polymer aggregate prepared in Preparation Example 1, 0.1 parts by weight of potassium persulfate, and 0.3 parts by weight of fatty acid saponification The reaction was completed by adding parts by weight, and when the polymerization conversion reached 95%, the reaction was terminated to prepare polybutadiene rubber latex having an average particle diameter of 763 nm. At this time, the total polymerization time was 16 hours.

Example 2

Polybutadiene rubber having an average particle diameter of 758 nm in the same manner as in Example 1, except that 0.5 parts by weight of the polymer aggregate prepared in Preparation Example 2 was added instead of the polymer aggregate prepared in Preparation Example 1 in Example 1 Latex was prepared.

Example 3

In Example 1, a polybutadiene rubber latex having an average particle diameter of 751 nm was prepared in the same manner as in Example 1, except that 0.01 parts by weight of the polymer aggregate prepared in Preparation Example 1 was added.

Example 4

In Example 1, a polybutadiene rubber latex having an average particle diameter of 775 nm was prepared in the same manner as in Example 1, except that 1.5 parts by weight of the polymer aggregate prepared in Preparation Example 1 was added.

Comparative Example 1

In Example 1, polybutadiene having an average particle diameter of 480 nm was carried out in the same manner as in Example 1, except that 0.5 parts by weight of the polymer aggregate prepared in Comparative Preparation Example 1 was added instead of the polymer aggregate prepared in Preparation Example 1. A rubber latex was prepared.

Comparative Example 2

Polybutadiene having an average particle diameter of 998 nm in the same manner as in Example 1, except that in Example 1, 0.5 parts by weight of the polymer aggregate prepared in Comparative Preparation Example 2 was added instead of the polymer aggregate prepared in Preparation Example 1 A rubber latex was prepared.

Comparative Example 3

In Example 1, polybutadiene rubber latex having an average particle diameter of 270 nm was prepared in the same manner as in Example 1, except that 0.005 parts by weight of the polymer aggregate prepared in Preparation Example 1 was added.

Comparative Example 4

In Example 1, a polybutadiene rubber latex having an average particle diameter of 1101 nm was prepared in the same manner as in Example 1, except that 2.0 parts by weight of the polymer aggregate prepared in Preparation Example 1 was added.

Comparative Example 5

Polybutadiene having an average particle diameter of 572 nm in the same manner as in Example 1, except that in Example 1, 0.5 parts by weight of the polymer aggregate prepared in Comparative Preparation Example 3 was added instead of the polymer aggregate prepared in Preparation Example 1 A rubber latex was prepared. At this time, the total polymerization time was 16.5 hours.

Comparative Example 6

In Example 1, polybutadiene rubber latex having an average diameter of 994 nm was prepared in the same manner as in Example 1, except that potassium persulfate and fatty acid saponification were not added when the polymer aggregate was added. At this time, the total polymerization time was 18 hours.

Experimental Example 1

Latex stability, solid coagulation content, average particle size and particle distribution (weight ratio according to particle size) and particle circularity of each latex prepared in Examples 1 to 4 and Comparative Examples 1 to 6 were comparatively analyzed, and the results are as follows. Table 1 shows.

1) Latex stability (wt%)

After latex stability, 500 g of each latex was filtered using a 100 mesh net, it was put into a homo mixer (trade name: T.K.ROBOMICS, manufacturer: T.K. Primix), and then left at 12,000 RPM for 60 minutes. Thereafter, the coagulated material caught in a 100 mesh net was measured and calculated according to Equation 4 below.

[Equation 4]

Latex Stability (% by weight) = [Weight of coagulation caught in 100 mesh net (g) / Theoretical total solids content of reactant including monomers used in the reaction (g)] × 100

2) Average particle diameter (㎛) and particle size distribution

The average particle size and particle size distribution (weight ratio according to particle size) were measured using a CHDF device (Capillary Hydrodynamic Fractionation, Matec Applied Science, Model 1100) after diluting 1 g of latex in 100 g of distilled water.

3) Solid coagulation content (% by weight)

After the latex was filtered through a 100 mesh wire mesh, the reaction product that did not pass on the wire mesh was dried in a hot air dryer at 100° C. for 1 hour to measure the weight of the coagulated product, and calculated by Equation 2 below.

[Equation 2]

Solid coagulation content (wt%) = [Coagulant weight (g) / Total reactant weight (g)] × 100

4) Particle circularity

The circularity of the latex particles was calculated as the ratio of the length of the long axis (major axis) / the length of the short axis (minor axis) of the particles and their average values. After analyzing each latex by TEM (JEM-1400, Jeol), 50 particles each The length of the major axis and the length of the minor axis were measured in , and the particle circularity was calculated through Equation 1 below.

[Equation 1]

In Equation 1, D _i is the ratio of the length of the major axis to the length of the minor axis in the i-th particle [length of the major axis/length of the minor axis].

As shown in Table 1 above, according to the manufacturing method presented in the present invention, the polymer aggregate having an average particle diameter of 230 to 300 nm was used in an amount of 0.01 to 1.5 parts by weight based on 100 parts by weight of the total monomer, and the poly of Examples 1 to 4 was prepared. The butadiene rubber latex has an average particle diameter of 600 to 800 nm, 17% to 21% by weight of the entire rubber particle represents a particle size of 100 nm or more and less than 300 nm, and 70% to 71% by weight is 300 nm or more and less than 800 nm of particle size, and 8 wt% to 12 wt% had a particle size distribution showing a particle diameter of 800 nm or more and less than 1000 nm, and had a spherical particle shape with a particle circularity of 1.05 to 1.06. In addition, the latex stability was excellent as the solid coagulation content was 0.01 wt% or less. In addition,

On the other hand, a comparison prepared by using a polymer aggregate having an average particle diameter of not 230 to 300 nm, or using a polymer aggregate having an average particle diameter of 230 to 300 nm but in an amount that is 0.01 to 1.5 parts by weight relative to 100 parts by weight of the total monomer. The polybutadiene rubber latex of Examples 1 to 4 had an average particle diameter of 600 to 800 nm, or did not exhibit the trimodal properties presented in the present invention, and latex stability was reduced.

On the other hand, Comparative Examples 5 and 6 used the polymer aggregate having an average particle diameter of 230 to 300 nm in an amount of 0.05 parts by weight relative to 100 parts by weight of the total monomer, but Comparative Example 5 had an average particle diameter of 600 to 800 nm, and the present invention It did not exhibit trimodal characteristics and did not have a uniform spherical shape with a particle circularity of 1.24. In addition, Comparative Example 6 deviates from the average particle diameter of 600 to 800 nm, did not exhibit the trimodal characteristics, and the latex stability was greatly reduced due to an increase in solid coagulation. In this case, in Comparative Example 5, the polymer aggregate was prepared without a crosslinking agent, and in Comparative Example 6, a water-soluble polymerization initiator was not used when the polymer aggregate was added. Through this, even if it is enlarged by the polymer aggregate having an average particle diameter of 230 to 300 nm, when a crosslinking agent is not used in the preparation of the polymer aggregate or when a water-soluble initiator is not used together when applying the polymer aggregate, a latex having excellent stability having desired particle properties It was confirmed that it could not be manufactured.

The above results indicate that the diene-based rubber latex having the particle characteristics (average particle diameter and particle size distribution) presented in the present invention can be achieved by using a specific amount of polymer aggregates having an average particle diameter in a specific range and being enlarged. In addition, it means that the above-mentioned particle properties can be achieved by using the polymer aggregate in the presence of a crosslinking agent and using it together with a water-soluble initiator in the production of diene-based latex.

Preparation of acrylonitrile-butadiene-styrene graft copolymer of core-shell structure

Example 5

3 parts by weight of the polybutadiene rubber latex prepared in Example 1, 57 parts by weight of the polybutadiene rubber latex having an average particle diameter of 0.3243 μm, and 100 parts by weight of ion-exchanged water were added to a nitrogen-substituted polymerization reactor (autoclave) and heated to 70° C. 10 parts by weight of acrylonitrile, 25 parts by weight of styrene, 20 parts by weight of ion-exchanged water, 0.1 parts by weight of tertiary hydroperoxide, 1.0 parts by weight of potassium rosinate and tertiary dode A mixed solution consisting of 0.3 parts by weight of mercaptan, 0.054 parts by weight of dextrose, 0.004 parts by weight of sodium picoliate, and 0.0002 parts by weight of ferrous sulfate were continuously added for 3 hours. After the input was completed, 0.05 parts by weight of dextrose, 0.03 parts by weight of sodium picoliate, 0.001 parts by weight of ferrous sulfate, and 0.005 parts by weight of tert-butyl hydroperoxide were batched in and reacted while raising the temperature to 80° C. over 1 hour. Then, the reaction was terminated to prepare an acrylonitrile-butadiene-styrene graft copolymer having a core-shell structure having a polymerization conversion rate of 98%. Thereafter, sulfuric acid was added to prepare an acrylonitrile-butadiene-styrene graft copolymer having a powdery core-shell structure through agglomeration, washing and drying processes.

Example 6

In Example 5, in the same manner as in Example 5, except that the polybutadiene rubber latex prepared in Example 2 was used instead of the polybutadiene rubber latex prepared in Example 1, and the powder core-shell structure acrylic A ronitrile-butadiene-styrene graft copolymer was prepared.

Example 7

In Example 5, in the same manner as in Example 5, except that the polybutadiene rubber latex prepared in Example 3 was used instead of the polybutadiene rubber latex prepared in Example 1, and powdered core-shell structure acrylic A ronitrile-butadiene-styrene graft copolymer was prepared.

Example 8

In Example 5, in the same manner as in Example 5, except that the polybutadiene rubber latex prepared in Example 4 was used instead of the polybutadiene rubber latex prepared in Example 1, and the powder core-shell structure acrylic A ronitrile-butadiene-styrene graft copolymer was prepared.

Example 9

In Example 5, 5 parts by weight of the polybutadiene rubber latex prepared in Example 1 and 55 parts by weight of the polybutadiene rubber latex having an average particle diameter of 0.3243 μm was used in the same manner as in Example 5, An acrylonitrile-butadiene-styrene graft copolymer having a core-shell structure was prepared.

Comparative Example 7

In Example 5, the polybutadiene rubber latex prepared in Example 1 was not used, and 60 parts by weight of the polybutadiene rubber latex having an average particle diameter of 0.3243 μm was used in the same manner as in Example 5. An acrylonitrile-butadiene-styrene graft copolymer having a core-shell structure was prepared.

Comparative Example 8

In Example 5, in the same manner as in Example 5, except that the polybutadiene rubber latex prepared in Comparative Example 1 was used instead of the polybutadiene rubber latex prepared in Example 1, the powder core-shell structure acrylic A ronitrile-butadiene-styrene graft copolymer was prepared.

Comparative Example 9

In Example 5, in the same manner as in Example 5, except that the polybutadiene rubber latex prepared in Comparative Example 2 was used instead of the polybutadiene rubber latex prepared in Example 1, the powder core-shell structure acrylic A ronitrile-butadiene-styrene graft copolymer was prepared.

Comparative Example 10

In Example 5, in the same manner as in Example 5, except that the polybutadiene rubber latex prepared in Comparative Example 3 was used instead of the polybutadiene rubber latex prepared in Example 1, and the powder core-shell structure acrylic A ronitrile-butadiene-styrene graft copolymer was prepared.

Comparative Example 11

In Example 5, in the same manner as in Example 5, except that the polybutadiene rubber latex prepared in Comparative Example 4 was used instead of the polybutadiene rubber latex prepared in Example 1, A ronitrile-butadiene-styrene graft copolymer was prepared.

Comparative Example 12

In Example 5, in the same manner as in Example 5, except that the polybutadiene rubber latex prepared in Comparative Example 5 was used instead of the polybutadiene rubber latex prepared in Example 1, and the powder core-shell structure acrylic A ronitrile-butadiene-styrene graft copolymer was prepared.

Comparative Example 13

In Example 5, in the same manner as in Example 5, except that the polybutadiene rubber latex prepared in Comparative Example 6 was used instead of the polybutadiene rubber latex prepared in Example 1, and a powder core-shell structure acrylic A ronitrile-butadiene-styrene graft copolymer was prepared.

Comparative Example 14

In Example 5, except that 1 part by weight of the polybutadiene rubber latex prepared in Example 1 and 59 parts by weight of the polybutadiene rubber latex having an average particle diameter of 0.3243 μm was used in the same manner as in Example 5, the powder of An acrylonitrile-butadiene-styrene graft copolymer having a core-shell structure was prepared.

Comparative Example 15

In Example 5, 7 parts by weight of the polybutadiene rubber latex prepared in Example 1 and 53 parts by weight of the polybutadiene rubber latex having an average particle diameter of 0.3243 μm were used in the same manner as in Example 5, An acrylonitrile-butadiene-styrene graft copolymer having a core-shell structure was prepared.

Experimental Example 2

Latex stability, solid coagulation, impact strength, flow index, tensile strength and surface gloss of each copolymer prepared in Examples 5 to 9 and Comparative Examples 7 to 15 were comparatively analyzed, and the results are shown in Table 2 below. .

At this time, after mixing 27 parts by weight of each copolymer powder and 83 parts by weight of SAN (92HR, LG CHEM), extrusion and injection were performed to produce a 1/4″-thick specimen, which had impact strength, flow index, tensile strength and surface It was used as a specimen for gloss measurement.

1) Latex Stability (min)

While each copolymer latex was stirred at 15,000 rpm using a homo mixer (T.K.ROBOMICS, T.K. Primix), the time for coagulation of the copolymer latex was measured. Here, if the coagulation time was 40 minutes or more, latex stability was classified as excellent.

2) solid coagulation powder

After the copolymer latex was filtered through a 100 mesh wire mesh, the reaction product that did not pass over the wire mesh was dried in a hot air dryer at 100° C. for 1 hour to measure the weight of the coagulated product, and calculated by Equation 2 below.

[Equation 2]

Solid coagulation content (wt%) = [Coagulant weight (g) / Total reactant weight (g)] × 100

3) Impact strength measurement

The specimen was measured using an impact strength measuring instrument (TINIUS OLSEN) according to ASTM D256.

4) Flow index (MI, g/10 min)

The specimen was measured under conditions of 220° C. and 10 kg according to ASTM D1238.

5) Tensile strength (kgf/cm ² )

Using the specimen, it was measured according to ASTM D638.

6) Surface gloss (GLOSS)

Using the specimen, it was measured at a 45° angle with a gloss meter in accordance with ASTM D528, and the larger the value, the better the gloss of the surface.

As shown in Table 2, Examples 5 to 9 according to the present invention had a solid coagulation content of 0.03% or less, and had excellent latex stability. This was improved, and especially the impact strength was greatly improved.

Claims (15)

Based on 100 wt% of the total rubber particles, 14 wt% to 26 wt% represents a particle diameter of 100 nm or more and less than 300 nm, 62 wt% to 81 wt% represents a particle diameter of 300 nm or more and less than 800 nm, 5 wt% to 14% by weight represents a particle diameter of 800 nm or more and less than 1000 nm, and an average particle diameter of 600 nm to 800 nm of diene-based rubber latex.
The method according to claim 1,
A diene-based rubber latex having a circularity of 1.05 to 1.10 as defined by the following Equation 1:
[Equation 1]

In Equation 1, D _i is the ratio of the length of the major axis to the length of the minor axis in the i-th particle in the latex [length of the major axis/length of the short axis].
The method according to claim 1,
The diene-based rubber latex,
A diene-based rubber latex comprising a unit derived from an unsaturated carboxylic acid or an ester monomer thereof and a unit derived from a comonomer having a functional group, and enlarged by a polymer aggregate having an average particle diameter of 230 nm to 300 nm.
4. The method according to claim 3,
The polymer aggregate comprises 85 wt% to 92 wt% of a unit derived from an unsaturated carboxylic acid or an ester monomer thereof, and 8 wt% to 15 wt% of a comonomer-derived unit having a functional group. .
4. The method according to claim 3,
The unsaturated carboxylic acid or its ester monomer is methyl methacrylate, ethyl methacrylate, butyl methacrylate, methyl acrylate, ethyl acrylate, acrylic acid, methacrylic acid, itaconic acid, maleic acid, fumaric acid, maleic anhydride, A diene-based rubber latex that is at least one selected from the group consisting of monobutyl fumarate, monobutyl maleate and mono-2-hydroxypropyl maleate.
4. The method according to claim 3,
The comonomer having the functional group is meta-acrylamide, acrylamide, or a combination thereof, diene-based rubber latex.
The method according to claim 1,
The diene-based rubber latex is a diene-based rubber latex comprising a solid content of 0.01% by weight or less.
a) preparing a primary polymer having a polymerization conversion of 30% to 40% by primary polymerization of a first conjugated diene-based monomer in the presence of an emulsifier and a fat-soluble polymerization initiator;
b) preparing a secondary polymer having a polymerization conversion of 60% to 70% by adding a water-soluble polymerization initiator to the first polymer and increasing the temperature;
c) preparing a tertiary polymer having a polymerization conversion rate of 85% to 93% by adding a second conjugated diene-based monomer to the secondary polymer and performing tertiary polymerization; and
d) adding a polymer aggregate having an average particle diameter of 230 nm to 300 nm and a water-soluble polymerization initiator to the tertiary polymer and performing quaternary polymerization;
The first conjugated diene-based monomer and the second conjugated diene-based monomer are used in a weight ratio of 80 to 95:5 to 20,
The method for producing the diene-based rubber latex according to claim 1, wherein the polymer aggregate is added in an amount of 0.01 to 1.50 parts by weight based on 100 parts by weight of the total amount of the first conjugated diene-based monomer and the second conjugated diene-based monomer.
9. The method of claim 8,
The polymer aggregate is based on 100 parts by weight of the total amount of the unsaturated carboxylic acid or its ester monomer and the comonomer having a functional group,
i) polymerizing 20 to 40 parts by weight of an unsaturated carboxylic acid or an ester monomer thereof in the presence of 0.1 to 0.2 parts by weight of a crosslinking agent; and
ii) adding 50 to 75 parts by weight of an unsaturated carboxylic acid or an ester monomer thereof and 5 to 10 parts by weight of a comonomer having a functional group at the time when the polymerization conversion rate of step i) is 85 to 95%, and polymerizing A method for producing a diene-based rubber latex produced by emulsion polymerization.
10. The method of claim 9,
The crosslinking agent is ethylene glycol dimethacrylate, diethylene glycol dimethacrylate, triethylene glycol dimethacrylate, 1,3-butylene glycol dimethacrylate, aryl methacrylate and 1,3-butylene glycol A method for producing a diene-based rubber latex that is at least one selected from the group consisting of diacrylates.
9. The method of claim 8,
The temperature increase in step b) is a method of producing a diene-based rubber latex by raising the temperature to an elevated temperature of 15 ℃ to 25 ℃ compared to the temperature during the primary polymerization.
9. The method of claim 8,
The first conjugated diene-based monomer and the second conjugated diene-based monomer is at least one selected from the group consisting of 1,3-butadiene, isoprene, chloroprene and piperylene.
rubbery polymer core; and
It surrounds the core and includes a shell including an aromatic vinyl-based monomer-derived unit and a vinyl cyan-based monomer-derived unit,
The rubbery polymer core contains 3 parts by weight to 5 parts by weight of the diene-based rubber latex having an average particle diameter of 600 nm to 800 nm and an average particle diameter of 310 nm to 330 nm of the diene-based rubber latex according to claim 1 based on 100 parts by weight of the core. A core-shell structure graft copolymer comprising 95 parts by weight to 97 parts by weight.
14. The method of claim 13,
The copolymer comprises 40% to 60% by weight of the core; and 40% to 60% by weight of the shell,
The shell is a core-shell structure graft copolymer comprising an aromatic vinyl-based monomer-derived unit and a vinyl cyan-based monomer-derived unit in a weight ratio of 3:1 to 2:1.
14. The method of claim 13,
The copolymer is a core-shell structure graft copolymer having a solid content of 0.03% by weight or less.