KR20160077627A - Preparation method of diene rubber latex and acrylonitrile-butadiene-styrene graft copolymer comprising the same - Google Patents

Abstract

The present invention relates to a method for producing diene-based rubber latex. The present invention further relates to an acrylonitrile-butadiene-styrene graft copolymer comprising the same. More specifically, the present invention relates to a method for producing diene-based rubber latex, an acrylonitrile-butadiene-styrene graft copolymer comprising the diene-based rubber latex produced therefrom and having improved low-temperature impact strength, and a thermoplastic resin comprising the same. According to the present invention, by regulating the content and the insertion timing of an emulsifying agent having the low critical micelle concentration (CMC) in the production of rubber latex, the ratio of the large caliber rubber latex and small caliber rubber latex is controlled.

Description

Butadiene-styrene graft copolymer containing the diene rubber latex and an acrylonitrile-butadiene-styrene graft copolymer containing the same,

The present invention relates to a process for preparing a diene rubber latex and an acrylonitrile-butadiene-styrene graft copolymer comprising the same, wherein the content of an emulsifier having a low critical micelle concentration (CMC) Butadiene-butadiene rubber latex having improved low-temperature impact strength by including a diene rubber latex prepared by controlling the ratio of a large-diameter rubber latex and a small-diameter rubber latex by controlling a time point, Styrene graft copolymers.

Generally, thermoplastic resins are widely used for electric, electronic parts, office equipment, automobile parts and the like due to relatively good physical properties such as impact resistance, mechanical strength, moldability and gloss.

ABS (Acrylonitrile-Butadiene-Styrene) (ABS) resin, which is a typical example of the thermoplastic resin, is an impact reinforcing agent and contains a conjugated diene rubber latex represented by polybutadiene having excellent rubber properties as a main component.

The diene rubber latex is prepared by emulsion polymerization. An aromatic vinyl compound and a vinyl cyan compound are mixed with the diene rubber latex and subjected to a graft reaction to obtain an acrylonitrile-butadiene-styrene graft copolymer and a thermoplastic resin containing the acrylonitrile- Can be manufactured.

The emulsion polymerization is easy to modify the prescription according to the required quality level, and at the same time, the product produced in the form of powder is subjected to an extrusion process to produce matrix resin (PSAN, PC, PBT, PVC, etc.) Weather resistance stabilizers, antistatic agents, antimicrobial agents, etc.) to produce various product groups.

On the other hand, the polymerization time and the particle size of the rubbery latex are closely related to each other in the production of rubbery latex by emulsion polymerization. That is, a prolonged polymerization time is required to obtain a large-diameter rubbery latex having a large particle diameter. In order to obtain a rubbery latex having a relatively large particle size in a relatively short period of time, a method of adding a small amount of an emulsifier and an additive such as a vinyl cyanide monomer prior to the initiation of polymerization, or a method of continuously introducing the emulsifier has been proposed.

However, this method also has a disadvantage in that the reaction time is longer than 30 hours in order to obtain the rubbery latex of large diameter, resulting in low productivity. In order to improve this, when emulsion polymerization is carried out under short reaction time and high reaction temperature conditions, the particle size of the rubber latex becomes small and the amount of the reaction coagulated product becomes large. In addition, There is a problem of lowering. Therefore, it is not easy to manufacture a large-diameter rubber latex having a high conversion rate in a short reaction time.

Particularly, in the case of a thermoplastic resin using a large-diameter rubber latex produced by a conventional method, there is a limitation in raising the surface gloss and a drawback that the low-temperature impact strength is significantly deteriorated. In order to improve this, a thermoplastic resin prepared by mixing a large-diameter rubber latex and a small-diameter rubber latex exhibits a relatively high low-temperature impact strength and a high surface gloss at the same time, The manufacturing process is complicated and the cost is increased because it includes a process of preparing and mixing the rubber latex.

In view of productivity and physical properties, many companies have attempted various methods for securing the physical properties of an ABS copolymer containing a large-diameter rubber latex and a small-diameter rubber latex and a thermoplastic resin containing the same.

SUMMARY OF THE INVENTION The present invention has been conceived to solve the problems of the prior art described above, and it is an object of the present invention to provide a method of mixing a rubber latex of a large diameter and a rubber latex of a small diameter by controlling the content of an emulsifier having a low critical micelle concentration (CMC) And to provide a method for producing a diene rubber latex having a controlled ratio.

Another object of the present invention is to provide a diene rubber latex produced from the above method.

Still another object of the present invention is to provide an acrylonitrile-butadiene-styrene graft copolymer having improved impact strength, gloss and low temperature impact strength by including the diene rubber latex and a thermoplastic resin containing the acrylonitrile-butadiene-styrene graft copolymer.

In order to solve the above problems, in one embodiment of the present invention

Wherein the first emulsifier is used in an amount of from about 1 part by weight to about 3 parts by weight, the polymerization initiator is from about 0.2 part by weight to about 0.4 part by weight, the electrolyte is from about 0.2 part by weight to about 3 parts by weight, And 65 parts by weight to 100 parts by weight of ion-exchanged water are charged into a reactor and polymerized;

10 parts by weight to 20 parts by weight of the conjugated diene-based monomer mixture and 0.1 to 1.0 part by weight of the second emulsifier are added at a polymerization conversion rate of 30% to 40% of the polymerization reaction and then polymerized;

3) a step of batchwise or continuously introducing the remaining amount of the conjugated diene-based monomer mixture and optionally 0 to 1 part by weight of the third emulsifier at a polymerization conversion rate of 60% to 70% of the polymerization reaction and polymerizing; And

And then terminating the polymerization by adding a polymerization inhibitor at a time when the polymerization conversion rate of the polymerization reaction is 92% or more, the method comprising:

And further adding 0.01 to 0.5 part by weight of a fourth emulsifier having a low critical micelle concentration (CMC) at a polymerization conversion rate of 50% to 85% of the polymerization reaction, to prepare a diene rubber latex do.

At this time, the fourth emulsifier may contain an emulsifier having a CMC of 150 mg / L or less.

Further, the present invention relates to a diene rubber latex prepared from the above-

The diene rubber latex includes a large-diameter diene rubber latex having an average particle diameter of 2,600 A to 5,000 A and a small-diameter diene rubber latex having an average particle diameter of 20 nm to 70 nm. The large-diameter rubber latex: The blend ratio of the latex is 98 wt% to 99.9 wt%: 0.01 wt% to 2 wt%.

The present invention also provides an acrylonitrile-butadiene-styrene graft copolymer comprising the diene rubber latex.

The present invention also provides a thermoplastic resin comprising the acrylonitrile-butadiene-styrene graft copolymer.

The method for producing a diene rubber latex according to the present invention is characterized in that a polymerization reaction is carried out by further adding an emulsifier having a low critical micelle concentration (CMC) at a polymerization conversion of 50% to 85% And a rubber latex having a small diameter can be controlled.

Further, by including it, the surface gloss and the low-temperature impact strength of the acrylonitrile-butadiene-styrene graft copolymer and the thermoplastic resin can be secured.

Therefore, the process for producing the diene rubber latex according to the present invention and the acrylonitrile-butadiene-styrene graft copolymer and the thermoplastic resin containing the diene rubber latex prepared therefrom are useful for industrial industries, As shown in Fig.

Hereinafter, the present invention will be described in detail in order to facilitate understanding of the present invention.

The terms and words used in the present specification and claims should not be construed as limited to ordinary or dictionary terms and the inventor may appropriately define the concept of the term in order to best describe its invention It should be construed as meaning and concept consistent with the technical idea of the present invention.

In one embodiment of the present invention

Wherein the first emulsifier is used in an amount of from about 1 part by weight to about 3 parts by weight, the polymerization initiator is from about 0.2 part by weight to about 0.4 part by weight, the electrolyte is from about 0.2 part by weight to about 3 parts by weight, And 65 parts by weight to 100 parts by weight of ion-exchanged water are charged into a reactor and polymerized;

10 parts by weight to 20 parts by weight of the conjugated diene-based monomer mixture and 0.1 to 1.0 part by weight of the second emulsifier are added at a polymerization conversion rate of 30% to 40% of the polymerization reaction and then polymerized;

3) a step of batchwise or continuously introducing the remaining amount of the conjugated diene-based monomer mixture and optionally 0 to 1 part by weight of the third emulsifier at a polymerization conversion rate of 60% to 70% of the polymerization reaction and polymerizing; And

And a polymerization inhibitor is added at a time when the polymerization conversion rate of the polymerization reaction is 92% or more to terminate the polymerization,

Adding 0.01 part by weight to 0.5 part by weight of a fourth emulsifier having a critical micelle concentration (CMC) at a polymerization conversion rate of 50 to 85% of the polymerization reaction to the diene rubber latex .

In the first stage of the polymerization, 60 parts by weight to 75 parts by weight of the conjugated diene monomer mixture, 1 part by weight to 3 parts by weight of the emulsifier, 0.1 part by weight of the polymerization initiator 0.2 parts by weight to 0.4 parts by weight of an initiator, 0.2 parts by weight to 3 parts by weight of an electrolyte, 0.1 parts by weight to 0.5 parts by weight of a molecular weight modifier and 65 parts by weight to 100 parts by weight of ion exchange water.

In the present invention, the conjugated diene-based monomer mixture may be composed of the conjugated diene-based monomer alone, or may be composed of the conjugated diene-based monomer, the aromatic vinyl-based monomer and the vinylcyanide-based monomer. That is, the conjugated diene-based monomer mixture means a conjugated diene-based monomer, or may mean a monomer mixture of a conjugated diene-based monomer, an aromatic vinyl-based monomer, and a vinylcyano-based monomer.

When the conjugated diene-based monomer mixture is the monomer mixture, the conjugated diene-based monomer mixture contains 55% by weight to 99.7% by weight of the conjugated diene-based monomer; 0.1% to 40% by weight of an aromatic vinyl monomer; And 0.1% to 40% by weight of a vinyl cyano monomer.

The conjugated diene monomer may be at least one selected from the group consisting of 1,3-butadiene, isoprene, chloroprene and p-terylene. Specifically, it may be 1,3-butadiene.

The aromatic vinyl-based monomer is not particularly limited, but may be one or more selected from the group consisting of styrene,? -Methylstyrene,? -Ethylstyrene and p-methylstyrene. Specifically, it may be styrene.

The vinylcyanic monomer is not particularly limited, but may be one or more selected from the group consisting of acrylonitrile, methacrylonitrile, and ethacrylonitrile. Specifically, it may be acrylonitrile.

The polymerization initiator is not particularly limited, and conventional ones known in the art can be used. For example, a water-soluble polymerization initiator such as persulfate, a fat-soluble polymerization initiator such as a peroxy compound, or an oxidation-reduction catalyst may be used.

The persulfate may be potassium persulfate, sodium persulfate, ammonium persulfate and the like. The fat-soluble polymerization initiator may be at least one selected from the group consisting of cumene hydroperoxide, diisopropylbenzene hydroperoxide, azobisisobutylonitrile, tertiary butyl hydroperoxide , Parramentane hydroperoxide, benzoyl peroxide, and the like. The oxidation-reduction catalyst may be sodium formaldehyde sulfoxylate, sodium ethylenediamine tetraacetate, ferrous sulfate, dextrose, sodium pyrophosphate, sodium sulfite, or the like.

The electrolyte may be selected from the group consisting of potassium chloride, sodium chloride, potassium bicarbonate, sodium bicarbonate, potassium carbonate, sodium carbonate, potassium sulfate, sodium sulfate, potassium hydrogen sulfite, sodium hydrogen sulfite, potassium pyrophosphate, sodium pyrophosphate, potassium phosphate, Sodium hydrogen, and the like.

Examples of the molecular weight modifier include, but are not limited to, mercaptans such as a-methylstyrene dimer, t-dodecyl mercaptan, n-dodecyl mercaptan and octyl mercaptan, halogenated hydrocarbons such as methylene chloride, methylene bromide Containing compounds such as tetraethylthiuram disulfide, dipentamethylenethiuramdisulfide, diisopropylkantogen disulfide, and the like. Preferably t-dodecylmercaptan.

In the second stage of polymerization, 10 to 20 parts by weight of the conjugated diene-based monomer mixture and 0.1 to 1.0 part by weight of the second emulsifier are added at a time when the polymerization conversion of the polymerization reaction is 30% to 40% to be.

The third stage of the polymerization is a step of continuously or continuously introducing the remaining amount of the conjugated diene-based monomer mixture and optionally 0 to 1 part by weight of the third emulsifier at a polymerization conversion rate of 60 to 70% of the polymerization reaction.

Wherein the first to third emulsifiers are each independently selected from the group consisting of allyl aryl sulfonate, alkaline methyl alkyl sulfate, sulfonated alkyl ester, fatty acid soap, rosin acid alkali salt, sodium lauryl sulfonate, potassium oleate, Sulfonate, poly-oxyethylene alkylphenyl ether, sodium dodecyl allylsulfosuccinate, C _{16 -18} alkenyl-succinic acid di-potassium salt (Alkenyl C _{16 -18} succinic acid, ), Sodium acrylamidostearate, polyoxyethylene alkylphenylether ammonium sulfate, or polyoxyethylene alkylphenyl ether ammonium salt. These solvents may be used singly or in combination, It does not.

In the above production method according to the present invention, the conjugated diene-based monomer mixture is divided into three stages (batchwise introduction and continuous introduction) according to the polymerization conversion time point, thereby easily forming a diene rubber latex having a proper particle size .

The above polymerization steps 1 to 3 according to the present invention may be such that polymerization is carried out under different temperature conditions, respectively.

Specifically, the first step may be performed at a temperature of 65 ° C to 70 ° C, the second step may be performed at a temperature of 72 ° C to 75 ° C, and the third step may be performed at a temperature of 80 ° C to 85 ° C ≪ / RTI > That is, the present invention may be to carry out the polymerization while gradually increasing the temperature condition as the polymerization proceeds.

In particular, the method of the present invention further comprises the step of adding 0.01 to 0.5 parts by weight of a fourth emulsifier having a critical micelle concentration (CMC) at a polymerization conversion of 50% to 85% .

In this case, the fourth emulsifier may be an emulsifier having a CMC of 150 mg / L or less, specifically an emulsifier having CMC of 10 mg / L or less or an emulsifier having CMC of 10 to 150 mg / L.

More specifically, when the fourth emulsifier contains an emulsifier having a CMC of 10 mg / L or less, 0.01 to 0.3 parts by weight of an emulsifier having a CMC of 10 mg / L or less at a polymerization conversion rate of 60% to 85% Can be input. In this case, the CMC 10 mg / L or less emulsifier is the typical example C _{16 -18} alkenyl Accommodation acid di-potassium salt, poly-oxyethylene alkyl phenyl ether, polyoxyethylene alkylphenyl ether ammonium sulfate (poly-oxyethylene alkylphenyl ether ammonium salt).

When the emulsifier having a CMC of 10 to 150 mg / L is included as the fourth emulsifier, 0.05 to 5 parts by weight of an emulsifier having a CMC of 10 to 150 mg / L at a polymerization conversion of 50 to 85% 0.5 part by weight may be added. The emulsifying agent having a CMC of 10 to 150 mg / L may be exemplified by fatty acid soap or potassium oleate, among which potassium oleate is exemplified.

The first emulsifier to the fourth emulsifier may be all the same or may be independently different from each other. For example, when the first emulsifier and the fourth emulsifier both contain potassium oleate, potassium oleate, which is the first emulsifier added at the beginning of the reaction, is added together with the electrolytic solution to form micales or particles, And has a different role from the fourth emulsifier which forms small-diameter rubber latex particles separately from the rubber particles which are initially injected.

That is, in the method of the present invention, the fourth emulsifier is added during the polymerization reaction to produce a small-diameter rubber latex simultaneously with the large-diameter rubber latex, It is possible to produce a thermoplastic resin capable of securing a low low-temperature impact strength reduction width.

Meanwhile, when the content of the fourth emulsifier is more than 0.5 parts by weight during the whole polymerization reaction, the low-temperature impact strength decreases and the high gloss is secured However, since the production rate of the small diameter is increased, the average particle size is decreased, and the impact strength is decreased compared with the conventional method. In addition to the deterioration of the physical properties, the viscosity of the polymerization is increased and the stability of the reaction is lowered . If the added amount is less than 0.01 part by weight, the resulting small diameter ratio becomes insignificant, or is used for stabilizing the conventional particle size, and it is difficult to exhibit the effect.

Further, when the conversion rate at the time of charging is low when the fourth emulsifier is added, for example, when the fourth emulsifier is added at a polymerization conversion rate of 50% or less, the generation rate of the small-diameter rubber latex is increased to provide a high gloss and a low low- It is hard to expect. Further, when the fourth emulsifier is added, when the conversion rate at the time of charging is high, for example, when the fourth emulsifier is added at a polymerization conversion rate of 80% or more, the monomer content not participating in the reaction is low, There are disadvantages.

On the other hand, when the fourth emulsifier contains an emulsifier having a high CMC, for example, 150 mg / L or more, it is not easy to simultaneously produce a large-diameter rubber latex and a small-diameter rubber latex.

The termination of the polymerization is a step of terminating the polymerization at a point of polymerization conversion of 92% or more in order to obtain a diene rubber latex.

The termination of the polymerization may be carried out using a polymerization inhibitor, and the polymerization inhibitor may be a conventional one known in the art.

Further, the present invention provides a diene rubber latex produced from the above-mentioned production process.

The diene rubber latex according to an embodiment of the present invention includes a large diameter diene rubber latex having an average particle diameter of 2,600 A to 5,000 A and a small diameter diene rubber latex having an average particle diameter of 20 nm to 70 nm, Wherein the mixing ratio of the large diameter rubber latex: small diameter rubber latex is 98 wt% to 99.9 wt%: 0.01 wt% to 2 wt%.

Here, A represents the unit of length used to express the wavelength of electromagnetic radiation, and 1 A equals 0.1 nm.

The diene rubber latex may have a gel content of 70% to 84% and a swelling index of 11-25.

At this time, the gel content indicates the degree of crosslinking in the polymer, that is, the degree of crosslinking of the polymer. The larger the gel content value, the higher the degree of crosslinking of the polymer.

The swelling index indicates the extent to which the polymer swells by the solvent, and the higher the degree of crosslinking of the polymer, the lower the swelling index.

As described above, the method of the present invention can change the physical properties of the thermoplastic resin by injecting approximately 0.01 to 0.5 part by weight of the emulsifier having a low CMC at a polymerization conversion of 50% to 85% of the polymerization reaction. That is, the large-diameter rubber latex and the small-diameter rubber latex can be produced at the same time, and the increase of the gel content and the decrease of the swelling index can be suppressed while the polymerization conversion rate is increased. As a result, it is possible to produce a thermoplastic resin having improved impact strength at low temperature and improved surface gloss while maintaining the conventional impact strength. On the other hand, small-diameter latex can be observed in the TEM analysis image on the rubber latex or in the particle size measuring apparatus, but the average particle size and the like are not significantly different.

In addition, the present invention provides an acrylonitrile-butadiene-styrene copolymer comprising the above-mentioned diene rubber latex.

The acrylonitrile-butadiene-styrene copolymer according to an embodiment of the present invention

40 to 70% by weight of the diene rubber latex of the present invention,

20 to 50% by weight of an aromatic vinyl compound, and

And 10 to 40% by weight of a vinyl cyan compound.

Specifically, the acrylonitrile-butadiene-styrene copolymer may have a graft rate of 25 to 35% and a resulting coagulum content of 0.01 to 0.1%, more specifically a graft rate of 33%, and a production coagulation of 0.05% Water content.

The acrylonitrile-butadiene-styrene copolymer according to the present invention is not particularly limited and can be produced by a conventional method known in the art. For example, an aromatic vinyl compound, a vinyl cyan compound, An emulsifier or the like may be added thereto, followed by emulsion polymerization, followed by coagulation and washing. At this time, the respective components may be added to the reactor through a method of collectively adding the components to the reactor, a method of continuously adding the components,

In order to facilitate the emulsion polymerization, additives such as a chelating agent, a dispersant, a pH adjuster, an oxygen scavenger, a particle size regulator, an anti-aging agent and an oxygen scavenger may be further used, The emulsion polymerization may be carried out usually at a temperature range of 10 ° C to 90 ° C, but may preferably be a temperature range of 25 ° C to 75 ° C.

Also, the coagulation is for forming an acrylonitrile-butadiene-styrene copolymer latex coagulate by agglomerating the acrylonitrile-butadiene-styrene copolymer latex composition formed after the emulsion polymerization, and it can be produced by a conventional method known in the art For example, by treating the composition with a salt aqueous solution or an aqueous acidic solution, and subjecting the composition to salt flocculation or acid flocculation.

The washing is to remove impurities (residual emulsifier, flocculant, etc.) from the acrylonitrile-butadiene-styrene copolymer latex coagulated through salt flocculation or acid flocculation to obtain an acrylonitrile-butadiene-styrene copolymer , And the coagulated material is added to an aqueous solution of an inorganic salt, followed by washing and drying.

At this time, the washing and drying are not particularly limited and can be carried out by a conventional method in the art.

Hereinafter, the present invention will be described in more detail with reference to Examples and Experimental Examples. However, the following examples and experimental examples are provided to illustrate the present invention and are not intended to limit the scope of the present invention.

Example

(Example 1)

1) Production of diene rubber latex

65 parts by weight of ion-exchanged water, 70 parts by weight of 1,3-butadiene, 1.5 parts by weight of potassium rosinate as the first emulsifier, 0.8 parts by weight of oleic acid potassium salt, (K ₂ CO ₃ ) as a polymerization initiator, 0.3 part by weight of tertiary dodecylmercaptan (TDDM) as a molecular weight modifier, and 0.3 part by weight of potassium persulfate (K ₂ S ₂ O ₈ ) (Step 1), 20 parts by weight of 1,3-butadiene was added to the mixture, and 0.3 part by weight of potassium rosinate was added to the mixture as a second emulsifier. ). At this time, to C _{16 -18} alkenyl Accommodation acid D, a polymerization conversion rate of 60% in the fourth emulsifier CMC 4.8 mg / L at this point, as shown in Table 1 to the potassium salt (Latemul ASK (Kao Corp., Japan) 0.04 parts by weight of the polymerization inhibitor were further added to the reaction and 15 parts by weight of the remaining 1,3-butadiene was added to the mixture in a batch to raise the temperature to 82 DEG C. (Step 3) Was added to terminate the polymerization, and a diene rubber latex was obtained.

2) Preparation of acrylonitrile-butadiene-styrene copolymer

65 parts by weight of the diene rubber latex prepared in 1) and 100 parts by weight of ion-exchanged water were charged into a polymerization reactor purged with nitrogen, 10 parts by weight of acrylonitrile mixed in a separate mixing device, 25 parts by weight of styrene, 20 parts by weight of water, 0.1 part by weight of t-butyl hydroperoxide, 1.0 part by weight of potassium rosinate and 0.3 part by weight of tertiary dodecyl mercaptan, 0.054 part by weight of dextrose, 0.004 parts by weight of sodium pyrophosphate, And 0.002 parts by weight of ferrous iron were continuously fed into the polymerization reactor at 70 DEG C for 3 hours. After the continuous introduction, 0.05 part by weight of dextrose, 0.03 part by weight of sodium pyrophosphate, 0.001 part by weight of ferrous sulfate and 0.005 part by weight of t-butyl hydroperoxide were fed into the polymerization reactor at the same time, After the temperature was raised over 1 hour, the reaction was terminated. The resulting acrylonitrile-butadiene-styrene copolymer latex was coagulated with an aqueous solution of sulfuric acid, washed, and dried to obtain a powdered acrylonitrile-butadiene-styrene copolymer.

3) Acrylonitrile-butadiene-styrene type thermoplastic resin

26 wt% of the acrylonitrile-butadiene-styrene graft copolymer powder and 74 wt% of a styrene-acrylonitrile resin (LG SAN 92 HR) were mixed and then pelletized using an extruder. A test piece of an acrylonitrile-butadiene-styrene thermoplastic resin was obtained by using a molding machine.

(Example 2)

Claim in CMC 4.8 mg / L of _{16 -18} C 4 alkenyl emulsifier Accommodation acid di-potassium salt (Latemul ASK (Kao Corp., Japan) 0.25 parts by weight, except that the polymerization conversion rate input in addition to the 61% of the time A diene rubber latex was prepared in the same manner as in Example 1.

Further, an acrylonitrile-butadiene-styrene copolymer and a thermoplastic resin specimen containing the same were obtained.

(Example 3)

A dienic rubber latex was prepared in the same manner as in Example 1 except that 0.35 part by weight of potassium oleate having a concentration of 35 mg / L of CMC as a fourth emulsifier was added at a polymerization conversion rate of 62%.

Further, an acrylonitrile-butadiene-styrene copolymer and a thermoplastic resin specimen containing the same were obtained.

(Example 4)

A dienic rubber latex was prepared in the same manner as in Example 1 except that 0.35 part by weight of potassium oleate having a concentration of 35 mg / L as a fourth emulsifier was added at a polymerization conversion rate of 73%.

Further, an acrylonitrile-butadiene-styrene copolymer and a thermoplastic resin specimen containing the same were obtained.

(Comparative Example 1)

A diene rubber latex was prepared in the same manner as in Example 1, except that no additional emulsifier was added during the production of the diene rubber latex.

Further, an acrylonitrile-butadiene-styrene copolymer and a thermoplastic resin specimen containing the same were obtained.

(Comparative Example 2)

And the above-described embodiment except that the input to the potassium salt (Latemul ASK (Kao Corp., Japan) 0.3 parts by weight, polymerization conversion rate 46% of the time - the fourth emulsifying C _{16 -18} Accommodation acid di-alkenyl of CMC 4.8 mg / L to 1, a diene rubber latex was prepared.

Further, an acrylonitrile-butadiene-styrene copolymer and a thermoplastic resin specimen containing the same were obtained.

(Comparative Example 3)

Fourth emulsifier CMC 4.8 mg / L of ₁₆ C _-18 alkenyl Accommodation acid di-potassium salt (Latemul ASK (Kao Corp., Japan) 0.52 parts by weight of the above embodiment except that the polymerization conversion rate input to the 61% of the time A diene rubber latex was prepared in the same manner as in Example 1.

Further, an acrylonitrile-butadiene-styrene copolymer and a thermoplastic resin specimen containing the same were obtained.

(Comparative Example 4)

A dienic rubber latex was prepared in the same manner as in Example 1 except that 0.06 part by weight of sodium laurylsulfonate having a concentration of 530 mg / L of CMC as the fourth emulsifier was added at a polymerization conversion of 60%.

Further, an acrylonitrile-butadiene-styrene copolymer and a thermoplastic resin specimen containing the same were obtained.

Experimental Example

( Experimental Example 1)

The physical properties such as the impact strength, the low temperature impact strength and the glossiness of each of the specimens prepared in Examples 1 to 4 and Comparative Examples 1 to 4 were measured, and the results are shown in Table 1 below.

1) Conversion ratio (%): The conversion ratios of the diene rubber latexes prepared in Examples 1 to 4 and Comparative Examples 1 to 4 were measured.

2) Impact strength: Each specimen was made to a 1/4 inch thickness and measured according to ASTM D256.

3) Low Temperature Impact Strength: The specimens subjected to the compression extrusion were placed in a low-temperature chamber at -20 ° C for about 2 hours, and then measured according to ASTM D256.

4) Gloss: Gloss was measured with a gloss meter at 45 degrees according to ASTM D-528. At this time, the larger the gloss value, the better the gloss.

Example Comparative Example One 2 3 4 One 2 3 4 Emulsifier Kinds CMC 4.8 mg / L CMC 35 mg / L - CMC 4.8 mg / L CMC 350mg / L content 0.04 0.25 0.35 0.35 - 0.3 0.52 0.06 When to put in (conversion rate) 60% 61% 62% 73% - 46% 61% 60% Conversion Rate (%) 92.7 93.1 92.8 92.7 92.5 93.5 94.0 92.6 Average particle size
(A) 3125 3063 3082 3102 3112 2650 2872 3110 Small diameter diameter
(TEM image) 30 to 70 nm 20 to 40 nm - 150 to 200 nm 30 to 70 nm Impact strength (1/4) 32.5 31.9 32.1 33.0 32.1 26.3 28.2 32.5 Glossiness (45) 92.1 97.2 95.3 93.9 86.3 98.5 96.7 88.0 Low temperature impact strength
(-20 [deg.] C.) 13.1 14.5 13.9 13.8 11.2 13.7 12.7 11.8 Large diameter: small diameter content ratio 99%: 1% 98%: 2% 98%: 2% - 98%: 2% 96%: 4% -

As shown in Table 1, in the case of Examples 1 to 4, in which the fourth emulsifier was added at a polymerization conversion rate of 60% to 72%, the conversion rate was similar to that of Comparative Example 1 in which the fourth emulsifier was not added High impact strength, gloss and low temperature impact strength.

On the other hand, in Comparative Example 2 in which the fourth emulsifier was placed at a polymerization conversion rate of 46%, it was confirmed that the glossiness was higher than that of Examples 1 to 4, but the impact strength was low. Also, Comparative Example 3 had a higher gloss and lower impact strength and low temperature impact strength than Examples 1 to 4 at the time of changing the input amount. In Comparative Example 4, small-diameter particles were not observed, and similar properties to those of Comparative Example 1 were exhibited.

Claims (24)

Wherein the first emulsifier is used in an amount of from about 1 part by weight to about 3 parts by weight, the polymerization initiator is from about 0.2 part by weight to about 0.4 part by weight, the electrolyte is from about 0.2 part by weight to about 3 parts by weight, And 65 parts by weight to 100 parts by weight of ion-exchanged water are charged into a reactor and polymerized;
10 parts by weight to 20 parts by weight of the conjugated diene-based monomer mixture and 0.1 to 1.0 part by weight of the second emulsifier are added at a polymerization conversion rate of 30% to 40% of the polymerization reaction and then polymerized;
3) a step of batchwise or continuously introducing the remaining amount of the conjugated diene-based monomer mixture and optionally 0 to 1 part by weight of the third emulsifier at a polymerization conversion rate of 60% to 70% of the polymerization reaction and polymerizing; And
And a polymerization inhibitor is added at a time when the polymerization conversion rate of the polymerization reaction is 92% or more to terminate the polymerization,
And further adding 0.01 part by weight to 0.5 part by weight of a fourth emulsifier having a critical micelle concentration (CMC) at a polymerization conversion of 50 to 85% of the polymerization reaction. Method of manufacturing latex.
The method according to claim 1,
Wherein the conjugated diene-based monomer mixture is composed of a conjugated diene-based monomer alone.
The method according to claim 1,
The conjugated diene-based monomer mixture
55% by weight to 99.7% by weight of a conjugated diene monomer;
0.1% to 40% by weight of an aromatic vinyl monomer; And
And 0.1 to 40% by weight of a vinyl cyanide monomer.
The method according to claim 2 or 3,
Wherein the conjugated diene-based monomer is a single substance selected from the group consisting of 1,3-butadiene, isoprene, chloroprene, and a mixture of two or more thereof.
The method of claim 3,
Wherein the aromatic vinyl-based monomer is at least one selected from the group consisting of styrene,? -Methylstyrene,? -Ethylstyrene, and p-methylstyrene.
The method of claim 3,
Wherein the vinyl cyanide monomer is at least one selected from the group consisting of acrylonitrile, methacrylonitrile, and ethacrylonitrile.
The method according to claim 1,
The first to third emulsifiers are each independently selected from the group consisting of allyl aryl sulfonate, alkaline methyl alkyl sulfate, sulfonated alkyl ester, fatty acid soap, rosin acid alkali salt, sodium lauryl sulfonate, potassium oleate, sodium alkylbenzenesulfonate , polyoxyethylene alkyl phenyl ether, sodium allyl FIG deosel seulpo succinate, C _{16 -18} alkenyl Accommodation acid di-potassium salt, sodium acrylamido stearate, polyoxyethylene alkylphenyl ether ammonium sulfate and polyoxyethylene An ether sulfate ester ammonium salt, or a mixture of two or more thereof.
The method according to claim 1,
Wherein the first step is carried out at a temperature of 65 ° C to 70 ° C.
The method according to claim 1,
Wherein the second step is performed under a temperature condition of 72 ° C to 75 ° C.
The method according to claim 1,
Wherein the step (3) is carried out at a temperature of 80 ° C to 85 ° C.
The method according to claim 1,
Wherein the fourth emulsifier comprises an emulsifier having a CMC of 150 mg / L or less.
The method of claim 11,
Wherein the fourth emulsifier comprises an emulsifier having a CMC of 10 mg / L or less or an emulsifier of 10 to 150 mg / L of CMC.
The method of claim 12,
Wherein the emulsifier having a CMC of 10 mg / L or less is further added at 0.01 to 0.3 part by weight at a polymerization conversion of 60% to 85% of the polymerization reaction.
The method of claim 12,
Emulsifiers of the CMC 10 mg / L or less is _-18 C ₁₆ alkenyl Accommodation acid di-potassium salt, poly-oxyethylene alkyl phenyl ether, and polyoxyethylene alkyl phenyl ether sulfate ammonium danilmul or a mixture of two or more selected from the group consisting of Based rubber latex.
The method of claim 12,
Wherein the emulsifier of 10 to 150 mg / L of CMC is further added in an amount of 0.05 to 0.5 part by weight at a polymerization conversion of 50% to 85% of the polymerization reaction.
16. The method of claim 15,
Wherein the emulsifier of 10 to 150 mg / L of CMC is a fatty acid soap or potassium oleate.
The method according to claim 1,
Wherein the first emulsifier to the fourth emulsifier are the same or different from each other.
As the diene rubber latex produced by the production method of claim 1,
The diene rubber latex includes a large-diameter diene rubber latex having an average particle diameter of 2,600 A to 5,000 A and a small-diameter diene rubber latex having an average particle diameter of 20 to 70 nm. The large-diameter rubber latex: Wherein the blend ratio of the latex is 98% by weight to 99.9% by weight: 0.01% by weight to 2% by weight.
19. The method of claim 18,
Wherein the diene rubber latex has a gel content of 70% to 84%.
19. The method of claim 18,
Wherein the diene rubber latex has a swelling index of from 11 to 25.
An acrylonitrile-butadiene-styrene copolymer comprising the diene rubber latex according to claim 18.
23. The method of claim 21,
The acrylonitrile-butadiene-styrene copolymer
40 to 70% by weight of the diene rubber latex according to claim 18,
20% to 50% by weight of an aromatic vinyl compound, and
Acrylonitrile-butadiene-styrene copolymer comprising 10% by weight to 40% by weight of a vinyl cyanide compound.
23. The method of claim 22,
Said copolymer having a graft rate of 25% to 35%, and
Acrylonitrile-butadiene-styrene graft copolymer having a resulting coagulation content of 0.01% to 0.1%.
A thermoplastic resin comprising an acrylonitrile-butadiene-styrene graft copolymer according to claim 21.