JP3313026B2 - Method for coagulating and enlarging diene-based polymer rubber latex, graft polymer and thermoplastic resin composition - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

TECHNICAL FIELD The present invention relates to an industrially advantageous diene polymer rubber latex having a high solid content without producing coagulated particles (rubber lumps) when performing a coagulation enlargement process in a stirring tank. The present invention relates to a method for increasing the cohesion of a diene-based polymer rubber latex and a method for producing a graft copolymer using the method .

[0002]

2. Description of the Related Art Generally, thermoplastic resins have excellent mechanical and chemical properties and are widely used in various fields, but have a low impact resistance. Has disadvantages. In order to remedy this drawback, ABS resin in which hard resin is reinforced with an elastic body, M
An impact-resistant modified resin such as a polymer obtained by graft polymerization of a monomer such as methyl methacrylate, styrene and acrylonitrile to a BS resin and a polyacrylic acid alkyl ester rubber polymer is blended with a thermoplastic resin to form an impact-resistant resin. There has been proposed a method for imparting property (Japanese Patent Laid-Open No. 57-102)
940, JP-A-60-235854 and JP-A-58-152039).

Conventionally, a rubber-enlarged rubber graft copolymer has been used to improve the impact resistance. As the rubber-enlargement technology, an enlargement technology using an electrolyte, a polymer organic acid latex, an acid or the like is used. Has already been reported.

[0004] Above all, a great deal of research on enlargement technology using acids has been carried out for a long time, and acid is added to a rubber-like polymer latex to lower the pH of the latex to reduce the agglomeration and enlargement of latex particles. It is well known that the method is followed by adding a basic substance to make the pH of the system alkaline and stabilize the latex.

The problem here is how to maintain the stability of the latex during coagulation and enlargement, and to obtain an enlarged latex without generating the generation of rubber lumps.

[0006] As a method for improving this point, a step of adding an acid to the rubber-like polymer latex to reduce the pH to less than 7.0 to increase the size and then adding a basic substance is performed at 40 ° C or higher, and the stirring strength is increased during graft polymerization. (Japanese Patent Publication No. 55-19246) and an acid is added to a rubbery latex using a fatty acid soap, and the acid is added in a shower or mist state to enlarge the mixture at a pH of 4.0 or less. A method (Japanese Patent Publication No. 2-9601) has been proposed.

[0007] Japanese Patent Publication No. 55-19246 discloses that the stirring strength is reduced to half or less of that during the graft polymerization, but there is no description as to the stirring strength at the time of the graft polymerization. Stirring strength is unknown. In addition, the stirring strength largely depends on the shape of the stirring blade, but the examples do not describe the shape of the stirring blade at all. Further, the solid content concentration of the latex after the enlargement shown in the examples is 25% by weight or less, which is an example applicable only to a latex having a low solid content concentration in which rubber lumps are hardly generated. High productivity cannot be obtained.

[0008] Similarly, the method described in Japanese Patent Publication No. 2-9601 discloses a latex having a low solid content (the solid content of the enlarged latex shown in Examples is 21 to 23% by weight).
In this method, high productivity cannot be obtained even with this method.

Further, in this method, since the mixing of the acid and the latex is performed by letting the molecules diffuse in a non-agitated state, uniform aggregation is unlikely to occur. Even if uniform aggregation occurs, it takes a considerable time. , Poor productivity.

As an example of obtaining an enlarged latex having a high solid content, a method of continuously supplying the latex and an acid to a flow-type tubular apparatus in a coagulation step of adding an acid to a polymer latex (Japanese Patent Publication No. 7-21014),
A method in which an acidic and stable emulsifier is added to a polymer latex using an emulsifier whose surface activity is reduced due to acidity, an excessive amount of acid is added, and then a polymer latex is further added to enlarge the polymer (Japanese Patent Publication No. 7-118). No. 21012) has been proposed.

In Japanese Patent Publication No. Hei 7-21014,
Although an enlarged latex having a high solid content of 29 to 34.8% by weight is obtained (Examples 1 to 3), a flow-type tubular device is required separately from the stirring tank, and the equipment cost is low. It is not economical.

In the method described in Japanese Patent Publication No. Hei 7-21012, an enlarged latex having a high solid content (40% by weight) is obtained in a stirring tank.

However, this is because the latex before enlargement is a latex having an average particle size of 0.185 μm, and it takes a very long polymerization time to obtain such a latex having a large particle size (26 hours in the example). ), There is a problem in productivity before the bloat grows. Latex enlargement technology is a method for obtaining a large particle size latex in a short time, which requires an extremely long polymerization time in the emulsion polymerization method. This is a meaningful means.

In other methods, a method for increasing the stability of the latex is required. Unexpanded particles remain in the latex after enlargement, the particle size distribution is widened, and the improvement in impact resistance is insufficient. .

[0015]

Means for Solving the Problems The inventors of the present invention have conducted intensive studies to solve the above-mentioned problems, and as a result, the diene-based polymer rubber latex has been enlarged by agglomeration mainly comprising Brown agglomeration. A method of coagulating and enlarging a rubber latex that does not form a rubber mass and obtain an enlarged diene-based polymer rubber latex having a high solid content, and a method of producing a rubber manufactured using the enlarged diene-based polymer rubber latex. The present inventors have found that a thermoplastic resin composition using a soft copolymer has excellent impact resistance, and have reached the present invention.

The gist of the present invention is that diene polymer rubber latex obtained by emulsion polymerization is coagulated and enlarged to enlarge diene polymer rubber latex (A).
Is a method of performing agglomeration by agglomeration mainly comprising Brownian agglomeration, wherein Brownian agglutination is performed by setting the stirring rotation speed in a stirring tank to a rotation speed (Ns) or less represented by the following formula (1). Ns = (D0 / Ds) k × N0-(1) Formula Ds: Stirring blade diameter (mm) Ns: Coagulation and enlargement step K, D0, N0 are constants determined by the shape of the stirring blade. Propeller wing: k = 0.60, N0 = 450, D0 = 6
0 Swept wing: k = 0.46, N0 = 300, D0 = 6
0 paddle wing: k = 0.50, N0 = 270, D0 = 7
0 Large plate wing: k = 0.55, N0 = 200, D0 = 8
0 and a method for producing a graft copolymer using the enlarged diene polymer rubber latex (A) obtained by the method.

[0017]

BEST MODE FOR CARRYING OUT THE INVENTION Brown aggregation in the present invention means that latex particles collide and aggregate by performing Brownian motion. Usually, the aggregation of latex is mainly caused by Brown aggregation and shear aggregation, but the shear aggregation is a type of agglomeration caused by the latex particles colliding and moving due to the flow generated by applying shear by stirring or the like. is there.

The present inventors have found that the larger the contribution of brown agglomeration is, the larger the agglomeration and enlargement of the rubber latex is, the less the occurrence of rubber lumps and the more stable a latex is obtained. In order to increase the contribution of brown agglomeration, the shear applied to the latex may be reduced, and complete brown agglomeration can be achieved under no shear. While complete brown coagulation can completely suppress the generation of rubber lumps, it requires a great deal of time to mix the latex and coagulant under no shearing, leading to lower productivity. become.

Thus, the object of the present invention can be achieved by applying a gentle shearing to the extent that no rubber lumps are generated, thereby promoting the mixing of the coagulant and performing coagulation enlargement.

In addition, since the coagulation enlargement is performed by a method mainly based on Brown coagulation, the enlargement based on the chemical stability can be performed. A particle size distribution having a diameter was taken, and it was found that the number of unexpanded particles was extremely small.

That is, the greatest feature of the present invention is that the coagulation enlargement is performed by a method mainly comprising Brown coagulation in which shear coagulation is suppressed as much as possible.

The diene polymer rubber latex used in the present invention is obtained by conventional emulsion polymerization.
Latex of polybutadiene and a copolymer of butadiene at 50% by weight or more and a monomer copolymerizable with butadiene.

Examples of monomers copolymerizable with butadiene include aromatic vinyl monomers such as styrene and α-methylstyrene, and alkyl (meth) acrylates such as methyl methacrylate and n-butyl acrylate. And unsaturated nitrile monomers such as acrylonitrile.

Further, crosslinkable monomers such as divinylbenzene, ethylene glycol dimethacrylate, 1,3 butanediol diacrylate and allyl methacrylate can be used in combination.

The monomer copolymerizable with butadiene and the crosslinkable monomer can be used alone or as a mixture. The diene-based polymer may be t-
Dodecyl mercaptan, n-octyl mercaptan, α
-A chain transfer agent such as methylstyrene dimer can also be used.

The number average particle diameter of the diene polymer rubber latex is preferably 0.15 μm or less, more preferably 0.1 μm or less.

Even if the number average particle diameter of the diene polymer rubber latex exceeds 0.15 μm, there is no hindrance to the agglomeration step, but the number average particle diameter is 0.15 μm by emulsion polymerization.
If a diene polymer rubber latex exceeding μm is to be obtained, a long-time polymerization is required, and the productivity during the emulsion polymerization is reduced, and the effect of improving the productivity in the aggregation step is reduced.

Further, since the solid content concentration of the diene-based polymer rubber latex after the enlargement is preferably 30% by weight or more, the solid content concentration is reduced at the time of addition and neutralization of the acid aqueous solution. In view of the above, the diene polymer rubber latex solid content concentration is preferably 35% by weight or more,
More preferably, it is at least 40% by weight.

In the present invention, the solid content concentration of the enlarged diene polymer latex (A) is preferably 30% by weight.
The content is more preferably 35% by weight or more .

If the solid content concentration of the enlarged diene polymer rubber latex (A) is less than the above range, the productivity tends to decrease.

Next, the enlarged diene-based polymer rubber latex (A) used in the present invention can be obtained by using the above-mentioned diene-based polymer rubber latex by an enlargement method mainly based on brown agglomeration.

In the present invention, the method mainly based on Brownian agglomeration is not particularly limited in the apparatus and process, but the stirring is performed in a stirring tank at a rotational speed (Ns) or less as shown in the following formula (1).

Ns = (D0 / Ds) k × N0 --- Formula (1) Ds: diameter of stirring blade (mm) Ns: limit stirring rotation speed (rpm) in the coagulation enlargement process k, D0, N0 are stirring blades A constant determined by the shape.

Propeller wings: k = 0.60, N0 = 450, D0 = 60 Swept wings: k = 0.46, N0 = 300, D0 = 60 Paddle wings: k = 0.50, N0 = 270, D0 = 70 Large plate-like blade: k = 0.55, N0 = 200, D0 = 80 According to the above equation (1), the critical rotation speed (Ns: rpm) during the aggregation step is determined according to the diameter of the stirring blade and the type of stirring blade. You can ask. If the stirring is performed at a rotation speed of Ns (rpm) or more, rubber lumps may be generated, and there is a risk that productivity may be reduced.

The propeller blade referred to in the present invention is a stirring blade as shown in FIGS. 1 and 2, and the shape is not particularly limited, but the number of blades is 3 to 4 and the angle of the root of the blade (FIG. 1).
It is preferable that the angle (indicated by 1 in FIG. 1) is 0 ° to 50 ° and the maximum inclination angle of the blade (indicated by 2 in FIG. 1) is 30 ° to 75 °.

The retreating wing mentioned above is a stirring wing represented by the three-way retreating wing shown in FIGS. 3 and 4, and is not limited in shape, but has 3 to 4 blades and a retreat length (FIG. 4
The length indicated by 5 in FIG. 3) is 0.05 to 0.3 times the blade diameter (twice the length indicated by 6 in FIG. 4), and the tip height (shown by 4 in FIG. 3). Is the blade diameter (2 of the length indicated by 6 in FIG. 4).
Times), and the blade height (length indicated by 7 in FIG. 5) is 0.1 to 0.2 times the blade diameter (double the length indicated by 6 in FIG. 4). 0.5 times is preferable.

Further, the paddle blade referred to above is a stirring blade as shown in FIGS. 6 and 7, and the shape is not particularly limited. However, the number of blades is 2 to 6, and the inclination angle (8 in FIG. 6). Preferably, the blade angle (shown angle) is 0 to 45 °, and the blade height (length indicated by 9 in FIG. 6) is 0.1 to 0.5 times the blade diameter 10.

Further, the large plate-like wing mentioned above is a full zone wing (manufactured by Shinko Pantech Co., Ltd.) shown in FIGS.
A rotating shaft 11 close to the tank bottom
Radiation-type bottom wing 13 installed in the rotating shaft 11
The upper wing 12 has a radial flow type (one or more stages) phase-shifted by 90 degrees or less in the rotational direction with respect to the lower wing vertically adjacent thereto, and opposes the vertically adjacent wings. FIG. 10 shows a wing in which the radial end portions of the wing tip overlap each other in the vertical direction.
A paddle 16 that stirs the bottom of the tank is mounted below the rotary shaft 15, and a rotary shaft 1 is mounted above the rotary shaft 15.
5 is a wing or the like equipped with a lattice wing 19 comprising a horizontal member 17 extending horizontally from the member 5 and a member 18 extending at right angles from the horizontal member.

The size of the stirring blade (14 in FIGS. 8 and 9;
10) in FIG. 10 can be set to any size according to the size of the stirring tank, but is preferably from 0.3 times the diameter of the stirring tank.
0.8 wings are preferred.

In order to promote the mixing of the aqueous solution of the flocculant, it is possible to install a baffle plate and perform eccentric stirring within a range in which no rubber mass is formed.

When the baffles are installed, it is preferable that the number of the baffles is four or less, and that the lower end of each baffle is higher than the upper end of the stirring blade. When performing eccentric stirring, it is preferable that the horizontal distance from the center of the stirring tank to the center of the stirring shaft be 0.2 times or less the diameter of the stirring tank.

In the present invention, the stirring and holding time in the aggregating step is not particularly limited, but is preferably as short as possible, preferably 60 minutes or less, and more preferably 20 minutes as long as the mixing of the aggregating agent aqueous solution is completely performed. It is as follows.

In the present invention, the diene polymer latex is obtained by emulsion polymerization using a fatty acid soap as an emulsifier, and after adding an acidic emulsifier having a good surface activity in the coagulation enlargement step. It is preferable to add a coagulant to adjust the pH to 5 or less, and then neutralize with a basic substance to coagulate and enlarge the diene polymer rubber latex.

The fatty acid soaps used as emulsifiers include:
Although not particularly limited, for example, mixed fatty acid sodium,
Examples include mixed fatty acid potassium, sodium oleate, potassium oleate, sodium stearate, potassium stearate, disproportionated potassium rosinate, and the like. These fatty acid soaps can be used alone or in combination.

The amount of the fatty acid soap to be added may be an amount necessary for maintaining the stability of the latex during emulsion polymerization, and is not particularly limited.
It is 0.5 to 5 parts by weight with respect to parts by weight.

The emulsifier used in the coagulation enlargement step and having an acidic and good surface activity is not particularly limited, but is preferably an emulsifier having a sulfonic acid group and a salt of an alkali metal. Polyoxyethylene alkyl ether sulfe-
, Sodium alkyldiphenyletherodisulfonate, sodium alkylnaphthalenesulfonate, sodium dialkylsulfosuccinate and the like can be used alone or in combination.

The amount of the emulsifier having an acidic and good surface activity is 0.01 to 0.5 part by weight, preferably 0.1 to 100 parts by weight, based on 100 parts by weight of the solid content of the diene polymer latex. ０．３0.3 parts by weight.

When the addition amount of the emulsifier is less than 0.01 part by weight, a large amount of rubber lumps may be generated by adding the coagulant. On the other hand, when the addition amount exceeds 0.5 parts by weight, the effect of adding the coagulant to enlarge the diene polymer rubber latex particles is reduced.

The timing of adding the emulsifier which is acidic and does not decrease the surface activity is not particularly limited as long as it is before the enlargement.

In the present invention, it is preferable to use an aqueous acid solution as the coagulant. The flocculant is added so that the pH of the system is 5 or less. PH of the system is 5
When the aqueous solution of the flocculant is added only in an amount not less than the following,
Sufficient hypertrophy effect cannot be obtained. As the acid of the coagulant (acid) aqueous solution, an inorganic acid such as sulfuric acid, hydrochloric acid, phosphoric acid, or the like, or an organic acid such as acetic acid, formic acid, lactic acid, acrylic acid, methacrylic acid, etc., is not particularly limited.

The concentration of the aqueous solution of the flocculant is desirably as high as possible from the viewpoint of productivity within a range that does not cause rubber lumps at the time of addition. Must be set by type. For example, the concentration of a sulfuric acid aqueous solution is 0.1.
The concentration is 3 to 10% by weight, preferably 0.5 to 5% by weight, but the concentration in the case of an aqueous acetic acid solution is 3 to 40% by weight, preferably 5 to 20% by weight.

The method of adding the aqueous coagulant solution is not particularly limited, but it is preferable to slowly add the acid aqueous solution while stirring the diene polymer rubber latex in a stirring tank, and it is preferable to add the diene polymer rubber latex alone or immersed in the latex liquid. A method of gently injecting from a plurality of nozzles, a method of gently injecting from a drain port of a stirring tank, and the like are preferable.

The basic substance used for neutralization in the present invention is not particularly limited, but sodium hydroxide, potassium hydroxide, sodium carbonate, potassium carbonate and the like are preferable, and among them, an aqueous solution of sodium hydroxide and potassium hydroxide is more preferable. . Even if the concentration of the aqueous solution of the basic substance is high, there is no problem that a rubber mass is generated. However, when the concentration is low, the amount of the liquid increases and the solid content of the final polymer latex decreases, which is not preferable. The concentration of the aqueous solution of the basic substance is usually preferably 5 to 60% by weight.

In the present invention, the temperature of the system at the time of performing the aggregation step is not particularly limited, but the temperature is preferably from 10 ° C. to 60 ° C.

In the present invention, the average particle size of the enlarged diene-based polymer rubber latex (A) is adjusted to a pH of 7 after changing the acid amount and the amount of an emulsifier having an acidic and good surface activity. The control can be carried out arbitrarily by changing the content within the following range, preferably within the range of 5 or less. However, when used as an impact modifier for thermoplastic resins, the number average particle size is 0.15 μm. ~ 0.5 μm and
It is preferable that particles having a particle size of 0.15 μm or less be 10% by weight or less.

Method for producing the graft copolymer (B) of the present invention
The method comprises adding an aromatic vinyl-based monomer, a (meth) acrylate-based monomer, and an unsaturated nitrile to an enlarged diene-based polymer rubber latex (A) which is enlarged by agglomeration mainly based on Brownian agglomeration. At least one monomer selected from the group consisting of a system monomer and a monomer copolymerizable therewith is subjected to one-step or multi-step graft polymerization.

The content of the enlarged diene rubber polymer latex (A) in the graft polymer (B) is preferably 55 to 85% by weight as a solid content. If the amount is less than 55% by weight, the impact resistance is insufficiently developed. If the amount exceeds 85% by weight, other excellent properties of the thermoplastic resin (C) tend to be lost, which is not preferable.

The aromatic vinyl monomers to be graft-polymerized include styrene, α-methylstyrene, various halogen-substituted and alkyl-substituted styrenes, and the (meth) acrylate monomers to be graft-polymerized include:
Methacrylates such as methyl methacrylate, ethyl methacrylate, propyl methacrylate, glycidyl methacrylate, methyl acrylate, ethyl acrylate,
Acrylates such as butyl acrylate and glycidyl acrylate are unsaturated nitrile-based monomers to be graft-polymerized, and acrylonitrile, methacrylonitrile, etc. are graft-polymerizable with these monomers. Are aromatic polyfunctional vinyl compounds such as divinylbenzene and divinyltoluene; polyhydric alcohol dimethacrylates such as ethylene glycol dimethacrylate and 1,3 butanediol diacrylate; polymethacrylates such as trimethacrylic acid esters and triacrylic acid esters. Meta)
Examples thereof include allyl carboxylate such as acrylate, allyl acrylate and allyl methacrylate, di- and triallyl compounds such as diallyl phthalate, diallyl sebacate and triallyl triazine, and allyl glycidyl ether.

When the graft copolymer (B) is mixed with the vinyl chloride resin, the impact resistance is improved and
To increase the compatibility, methyl methacrylate is used as a monomer to be graft-polymerized, but a vinyl monomer copolymerizable therewith may be used if necessary.

The graft polymerization is preferably carried out in three stages, the first stage comprising methyl methacrylate as a main component and used for improving impact resistance and increasing the compatibility with the vinyl chloride resin. Is carried out in order to increase the fluidity of the graft copolymer in order to increase the fluidity of the graft copolymer, and to increase the gloss of the surface of the obtained thermoplastic resin composition in the third stage.

The monomers used for these graft polymerizations can be used alone or as a mixture.

The graft polymerization can be synthesized by a conventional emulsion polymerization in the same manner as the rubber polymerization. Although the polymerization temperature depends on the type of the polymerization initiator, the polymerization can be appropriately performed in a range of about 40 to 80 ° C.

The obtained graft copolymer (B) latex may or may not be added with an appropriate antioxidant or additive, or may be added with an acid such as sulfuric acid, hydrochloric acid or phosphoric acid, calcium chloride, or the like.
The coagulant is coagulated by using a coagulant such as a salt such as sodium chloride as appropriate, solidified by heat treatment, dried, washed and dried to obtain a powdery graft copolymer (B).

The graft copolymer (B) contains epoxidized soybean oil or 1,4-dihydro
2,6-dimethyl 3,5-dicarbododecyloxy
Stabilizers such as pyridine can be added. Further, silica powder or the like can be added in order to improve the handling property of the powder.

1 to 30% by weight of the graft copolymer (B) obtained by the present invention is a thermoplastic resin (C) of 99 to 7%.
By mixing with 0% by weight, a thermoplastic resin composition having excellent impact resistance can be obtained. When the amount of the graft copolymer (B) is less than 1% by weight, there is almost no effect of addition, and when the amount exceeds 30% by weight, other excellent properties of the thermoplastic resin (C) tend to be lost. Absent.

The thermoplastic resin (C) is not particularly limited. When a polyvinyl chloride resin is used, the polyvinyl chloride resin may be a chlorine-containing resin such as polyvinyl chloride or chlorinated vinyl chloride, or 70% by weight. % Of vinyl chloride and 30% by weight or less of another monomer copolymerizable therewith. Other copolymerizable monomers include vinyl bromide, vinylidene chloride, vinyl acetate,
Examples include acrylic acid, methacrylic acid, and ethylene.

The thermoplastic resin composition of the present invention is obtained by mixing the above graft copolymer (B) and the thermoplastic resin (C) in powder form with a ribbon blender, a Henschel mixer, or the like, and using a known kneader, extruder, or the like. Formed by A method of mixing the thermoplastic resin (C) and the graft copolymer (B) and pulverizing them through coagulation, solidification, washing, drying and the like may be used. When mixing by these various methods, known stabilizers, plasticizers, processing aids, coloring agents, and the like can be added as necessary.

[0068]

The present invention will be described below in detail with reference to examples. The present invention is not limited to the following examples as long as it does not exceed the scope of the gist. In the Examples and Comparative Examples, “parts” and “%” mean “parts by weight” and “% by weight”, respectively.

Various physical properties in the following Examples and Comparative Examples were measured by the following methods.

Number average particle diameter and particle diameter distribution The number average particle diameter was determined by kneading at 185 ° C. using a 6-inch roll, press-molding at 50 kg / cm ² and 185 ° C., and analyzing the image using a TEM. And measured. The particle size distribution was expressed as a percentage by weight of unexpanded small particles.

Scale (Lump) After Enlargement The amount of scale (lump) after enlargement was obtained by drying the generated scale and expressing the amount in% by weight based on the amount of charged monomers.

Kneading at 185 ° C. using a 6 inch roll, 50 kg /
After press molding at cm ^2, 185 ℃, ASTM D-
The measurement was performed according to 256.

Gloss of molded product A film molded to a thickness of 0.1 mm by a 30 mm uniaxial extruder was visually evaluated.

−- good, △-cloudy, ×-matte (Examples and Comparative Examples) (a) Polymerization of diene polymer rubber latex (a to c) [a] 1,3 butadiene 75 Parts Styrene 25 parts t-dodecyl mercaptan 0.3 parts diisopropylbenzene hydroperoxide 0.4 parts sodium pyrophosphate 1.5 parts ferrous sulfate 0.02 parts dextrose 1 part potassium oleate 1.5 parts Ionized water 150 parts Each of the charged components having the above composition was charged into a pressure-resistant autoclave and reacted at 60 ° C. for 8 hours with stirring to produce a diene polymer rubber latex.

The resulting diene polymer rubber latex has a number average particle size of 0.09 μm, a solid content of 40%,
H was 9.0.

[B] 1,3 butadiene 70 parts Styrene 30 parts 1,3 butylene glycol dimethacrylate 1.0 part Diisopropylbenzene hydroperoxide 0.4 parts Sodium pyrophosphate 1.5 parts Ferrous sulfate 0.02 1 part Dextrose 1 part Potassium tallowate 1.5 part Deionized water 180 parts Each of the charged components having the above composition was charged into a pressure-resistant autoclave, and reacted at 60 ° C. for 8 hours with stirring to obtain a diene system. A polymer rubber latex was produced.

The obtained diene polymer rubber latex has a number average particle size of 0.09 μm, a solid content of 36%, p
H was 9.1.

[C] 1,3 butadiene 100 parts t-dodecyl mercaptan 0.6 parts diisopropylbenzene hydroperoxide 0.4 parts sodium pyrophosphate 1.5 parts ferrous sulfate 0.02 parts dextrose 1 part 1.5 parts of sodium tallowate 170 parts of deionized water The charged components having the above composition were charged into a pressure-resistant autoclave, and reacted at 60 ° C. for 8 hours with stirring to produce a diene polymer rubber latex. did.

The obtained diene polymer rubber latex has a number average particle size of 0.08 μm, a solid concentration of 37%, and a p
H was 9.1.

(B) Preparation of stirring tank [Condition-1] 65 L stirring tank (inner diameter 400 mm, height 65
0 mm, made of SUS, without baffle), the number of blades on the stirring blade, the angle of the root of the blade (the angle shown as 1 in FIG. 1) and the maximum inclination angle of the blade (the angle shown as 2 in FIG. 1) Also, a propeller blade having a blade diameter of 180 mm and a diameter of 180 mm was used, and the center of the stirring blade was placed at a position 45 mm from the bottom on the central axis of the stirring tank.

[Condition-2] In [Condition-1], the number of stirring blades was six, the inclination angle was 0 ° (the angle indicated by 8 in FIG. 6), and the blade height was 30 mm (indicated by 9 in FIG. 6). Length), and the conditions were the same as in [Condition-1], except that the paddle blade was 210 mm in diameter.

[Condition-3] In [Condition-1], the number of blades of the stirring blade was three, the retreat length (the length indicated by 5 in FIG. 4) was 20 mm, and the height of the blade tip (in FIG. 3). (Length indicated by 4)
Is 10 mm and the blade height (the length indicated by 7 in FIG. 5) is 3
The conditions were the same as in [Condition-1], except that the three-way swept wing had a diameter of 0 mm and a wing diameter of 180 mm.

[Condition-4] 2.5 L stirring tank (inner diameter 135)
mm, height 200 mm, made of glass, without baffle), the number of blades on the stirring blade, the angle of the root of the blade (FIG. 1)
1) and the maximum inclination angle of the blade (FIG. 1).
Angle of 2) is 45 ° and the wing diameter is 60
Using a propeller blade having a diameter of 1 mm, the stirring blade was installed such that the center of the stirring blade was positioned at a position 15 mm from the bottom on the central axis of the stirring tank.

[Condition-5] In [Condition-4], the number of stirring blades was six, the inclination angle was 0 ° (the angle indicated by 8 in FIG. 6), and the blade height was 10 mm (indicated by 9 in FIG. 6). Length), except that the paddle wing was changed to 70 mm in diameter paddle wing.
4].

[Condition-6] In [Condition-4], the number of stirring blades was three, the retreat length (length indicated by 5 in FIG. 4) was 3.5 mm, and the blade tip height (FIG. 3). The length indicated by 4 in FIG. 5) is 30 mm, and the blade height (length indicated by 7 in FIG. 5)
Was changed to [condition-4] except that the diameter was changed to a three-way swept wing having a diameter of 10 mm and a blade diameter of 60 mm.

[Condition-7] In [Condition-4], the number of blades was four, the inclination angle was 45 ° (the angle indicated by 8 in FIG. 6), and the blade height was 10 mm (indicated by 9 in FIG. 6). Length), except that the paddle wing was changed to 70 mm in diameter paddle wing.
4].

[Condition-8] In [Condition-4], the lower blade has a diameter of 81 mm, the upper blade has a diameter of 74 mm, and the upper and lower stages have a phase shift of 45 °. The conditions were the same as in [Condition-4], except that the height was changed to a full zone blade whose height to the blade lower end was 100 mm.

[Condition-9] In [Condition-4], a paddle having a diameter of 80 mm and a height of 40 mm for stirring the bottom of the tank was attached to the lower part of the rotating shaft, and the upper part of the rotating shaft (at a position 25 mm and 50 mm above the upper end of the paddle). ), Two horizontal members having a diameter of 80 mm and a height of 10 mm extending horizontally from the rotation axis to the rotation axis, and 40 m each from the rotation axis of the upper horizontal member to both wings
The conditions were the same as in [Condition-4], except that a Max Blend blade equipped with a lattice blade composed of four members having a width of 10 mm and a height of 50 mm extending vertically below the horizontal member from the positions of m and 80 mm was used.

[Condition-10] Same as [Condition-3].

(C) Enlargement of diene-based polymer rubber latex [Conditions 1 to 3] 27 kg of the diene-based polymer rubber latex obtained in (a) and a good acid interface in the stirring tank prepared in (b). A 10% aqueous solution of an emulsifier having an activity was added as shown in Table 1 (Table 1 shows the number of emulsifiers per 100 parts of diene-based polymer rubber latex), and gently and sufficiently stirred.

Next, the stirring speed was set (described in Table 1).
The direction of the outlet of the L-shaped nozzle having an inner diameter of 10 mm is set in the same direction (circumferential direction) as the rotation direction of the stirring blade, and an acid aqueous solution (concentration and amount is described in Table 1; (The amount is 100 parts by weight of diene polymer rubber latex) was added to the latex over 7 minutes. Thereafter, the stirring was maintained for 10 minutes. The pH of the system is shown in Table 1.

Thereafter, an aqueous alkali solution (concentration and amount are shown in Table 1, concentration is% by weight, amount is parts per 100 parts of diene-based polymer rubber latex) was added to complete the enlargement operation. Table 1 shows the solid content concentration, the number average particle diameter, the pH, and the amount of generated rubber lumps (scale) of the obtained coagulated and enlarged diene polymer rubber latex.

[Conditions 4 to 9] The diene polymer rubber latex 100 obtained in (a) was placed in the stirring tank prepared in (b).
0g and one of emulsifiers having good surface activity in acidic condition
The 0% aqueous solution is shown in Table 1 (Table 1 describes the number of emulsifiers per 100 parts of diene polymer rubber latex).
Addition and gentle stirring.

Next, the stirring rotation speed was set (described in Table 1).
The direction of the outlet of the L-shaped nozzle having an inner diameter of 4 mm is set in the same direction (circumferential direction) as the rotating direction of the stirring blade, and the acid aqueous solution (concentration and amount is described in Table 1; (The amount is 100 parts by weight of diene polymer rubber latex) was added to the latex over 7 minutes. Thereafter, the stirring was maintained for 10 minutes. Table 1 shows the pH of the system.
It was shown to.

Thereafter, an aqueous alkaline solution (concentration and amount are shown in Table 1, concentration is% by weight, amount is part by weight with respect to 100 parts of diene polymer rubber latex) was added to complete the enlargement operation. Table 1 shows the solid content concentration, the number average particle diameter, the pH, and the amount of generated rubber lumps (scale) of the obtained coagulated and enlarged diene polymer rubber latex.

[Condition 10] The diene polymer rubber latex 27k obtained in (a) was placed in the stirring tank prepared in (b).
g of emulsifier having acidic and good surface activity
% Aqueous solution was added as shown in Table 1 (Table 1 describes the number of emulsifiers based on 100 parts of diene polymer rubber latex) and gently and thoroughly stirred.

Next, the stirring speed was set (described in Table 1).
The direction of the outlet of the L-shaped nozzle having an inner diameter of 10 mm is set in the same direction (circumferential direction) as the rotation direction of the stirring blade, and an acid aqueous solution (concentration and amount is described in Table 1; (The amount is 100 parts by weight of the diene polymer rubber latex) was added to the latex over 2 minutes. Thereafter, 1/4 of an aqueous alkali solution (concentration and amount are described in Table 1, concentration is% by weight, and amount is 100 parts by weight of diene polymer rubber latex) was added and stirred for 2 minutes. The addition of an acid and the addition of an alkali were repeated four times to complete the operation of enlargement.

Table 1 shows the solid content concentration, the number average particle diameter, the pH, and the amount of generated rubber lumps (scale) of the obtained coagulated and enlarged diene polymer rubber latex.

[0099]

[Table 1]

(D) Synthesis of Graft Copolymer (B) The above coagulated and enlarged diene-based polymer rubber latex was charged into a flask in an amount (as a solid content) shown in Table 2,
After nitrogen replacement, 1.5 parts of the same emulsifier used for rubber polymerization was added as a 7% aqueous solution to stabilize. Then, 0.6 parts of Rongalite was added, and the internal temperature was maintained at 70 ° C.
When the total amount of the monomer / monomer mixture in the first stage of the graft and the monomer / monomer mixture in the first stage of the graft and the total amount of the monomers and the monomer mixture in the amount shown in Table 2 are 100 parts, the amount is 0.1%. 2 parts of cumene hydroperoxide (CH
The mixture to which P) was added was added dropwise over 1 hour, and then held for 1 hour.

Then, in the presence of the polymer obtained in the previous step, the second step was carried out in the amount of the monomer or monomer mixture of the second step as shown in Table 2; A mixture obtained by adding 0.2 parts of CHP to the total amount of the monomer monomer or the monomer mixture in the second stage was 100 parts, and the mixture was added dropwise over 1 hour, and then maintained for 1 hour.

Thereafter, in the presence of the polymers obtained in the first stage and the second stage, the amount of the monomer of the third stage grafted in the amount shown in Table 2 as the third stage or When the total amount of the monomer mixture and the monomer monomer or the monomer mixture at the third stage of the grafting was 100 parts, the amount was 0.1%.
The mixture to which 2 parts of CHP had been added was added dropwise over 1 hour and then maintained for 1 hour to terminate the polymerization.

The Graft Copolymer Latex 10 Obtained
0 parts by weight of 1,4-dihydro 2,6-dimethyl 3,
After 0.5 part of 5-dicarbododecyloxypyridine (DHP) is added, 2 parts of a 0.2% aqueous sulfuric acid solution is added as pure components to 100 parts by weight of the graft copolymer to cause coagulation and complete coagulation. If not coagulated, a 5% aqueous sodium chloride solution was added as necessary, and the mixture was solidified by heat treatment at 90 ° C. Thereafter, the coagulated product was washed with warm water and dried to obtain a graft copolymer powder.

(E) Preparation of a thermoplastic resin composition A polyvinyl chloride resin having an average degree of polymerization of 700 was used as the thermoplastic resin, 100 parts of the polyvinyl chloride resin, 3 parts of dioctyltin mercaptide as a stabilizer and a lubricant, and methabrene were used. (Registered trademark) P-550 (Mitsubishi Rayon Co., Ltd.)
2 parts), 1 part of Metablen (registered trademark) P-710 (manufactured by Mitsubishi Rayon Co., Ltd.) and each component of the powder of the graft copolymer resin (B) obtained in the above (3) were mixed with a Henschel mixer for 110 parts. The mixture was mixed for 10 minutes until the temperature reached ° C to obtain a polyvinyl chloride resin composition.

The impact strength and the gloss of the molded article molded using the obtained resin composition were measured. Table 2 shows the results.

[0106]

[Table 2]

[0107]

According to the agglomeration enlargement method of the present invention, it is possible to produce an enlarged rubber latex having a target particle diameter with good productivity without almost producing a rubber lump using a conventional stirring tank. A graft copolymer can be obtained by graft-polymerizing the enlarged rubber latex, and a thermoplastic resin composition excellent in impact resistance can be obtained by using the graft copolymer. It became possible to obtain.

[Brief description of the drawings]

FIG. 1 is a side view of a propeller blade used in the present invention.

FIG. 2 is a top view of a propeller blade used in the present invention.

FIG. 3 is a side view of a swept wing used in the present invention.

FIG. 4 is a top view of a swept wing used in the present invention.

FIG. 5 is a sectional view of a swept wing used in the present invention.

FIG. 6 is a side view of a paddle blade used in the present invention.

FIG. 7 is a top view of a paddle wing used in the present invention.

FIG. 8 is a side view of a large plate-like wing (full zone wing) used in the present invention.

FIG. 9 is a top view of a large plate-like wing (full zone wing) used in the present invention.

FIG. 10 is a side view of a large plate-like blade (max blend blade) used in the present invention.

[Explanation of symbols]

 1 Blade root angle 2 Blade maximum inclination angle 3 Blade diameter 4 Blade tip height 5 Retreat length 6 Blade radius (1/2 of diameter) 7 Blade height 8 Tilt angle 9 Blade height 10 Blade diameter 11 Rotation axis 12 Upper stage Wing 13 Bottom wing 14 Wing diameter 15 Rotation axis 16 Paddle 17 Horizontal member 18 Member extending at right angle from horizontal member 19 Lattice wing 20 Wing diameter

────────────────────────────────────────────────── ─── Continuation of the front page (56) References JP-A-7-48455 (JP, A) (58) Fields investigated (Int. Cl. ⁷ , DB name) C08C 1/00 C08F 6/18 C08F 279 / 02 C08L 51/04

Claims (2)

(57) [Claims] 1. A method for coagulating and expanding a diene polymer rubber latex obtained by emulsion polymerization to obtain an enlarged diene polymer rubber latex (A). A method for performing enlargement, wherein browning is performed in a stirring tank with a stirring rotation speed of not more than a rotation speed (Ns) shown in the following formula (1), wherein the coagulation of diene polymer rubber latex is performed. How to enlarge. Ns = (D0 / Ds) k × N0 --- (1) Formula Ds: Stirring blade diameter (mm) Ns: Limit stirring rotation speed (rpm) of coagulation and thickening process k, D0, N0 are determined by the shape of the stirring blade. constant. Propeller wing: k = 0.60, N0 = 450, D0 = 6
0 Swept wing: k = 0.46, N0 = 300, D0 = 6
0 paddle wing: k = 0.50, N0 = 270, D0 = 7
0 Large plate wing: k = 0.55, N0 = 200, D0 = 8
0 2. An aromatic vinyl monomer and (meth) are added to an enlarged diene polymer rubber latex having a number average particle diameter of 0.15 to 0.5 μm obtained by the method of claim 1. Graft copolymer in which at least one monomer selected from the group consisting of an acrylate monomer, an unsaturated nitrile monomer and a monomer copolymerizable therewith is graft-polymerized in one step or in multiple steps. A method for producing the combination (B).