JPH0971603A - Method for coagulating and enlarging diene polymer rubber latex, graft polymer and thermoplastic resin composition - Google Patents

Abstract

PROBLEM TO BE SOLVED: To coagulate and enlarge a diene-based polymer rubber latex to the latex having high solid concentration and useful as a raw material for a graft copolymer for impact resistant resin composition without producing rubber lumps by bringing the diene-based polymer rubber latex to Brownian coagulation. SOLUTION: A diene-based polymer rubber latex obtained by an emulsion polymerization is agitated, etc., e.g. in an agitation tank with a rotation number <=Ns expressed by formula: Ns=(Do/Ds)×k×No [Ns is a limited agitation number (rpm); Ds is the diameter of an agitation blade (mm); (k), No and Do are constants defined by the shape of the agitation blade; 0.60, 450, 60 for a propeller blade; 0.46, 300, 60 for a sweepback blade; 0.50, 270, 70 for a paddle blade; 0.55, 200, 80 for a large platy blade, respectively], to bring the latex to Brownian coagulation and the latex is coagulated and enlarged to an enlarged latex, etc., having >=30wt.% solid concentration and 0.15-0.5μm average particle size.

Description

Detailed Description of the Invention

[0001]

TECHNICAL FIELD The present invention relates to a diene polymer rubber latex having a high solid content concentration which is industrially advantageous and does not generate coagulated particles (rubber lumps) as a by-product during the coagulation and enlargement process in a stirring tank. The present invention relates to a method for coagulating and enlarging a diene polymer rubber latex, a graft copolymer using the enlarging method, and a thermoplastic resin composition for obtaining the same.

[0002]

2. Description of the Related Art Generally, thermoplastic resins have excellent mechanical properties and chemical properties and are widely used in various fields, but they are low in impact resistance. It has drawbacks. In order to improve this drawback, ABS resin in which hard resin is reinforced with elastic body, M
Impact resistance-modified resin such as BS resin and polyacrylic acid alkyl ester rubber polymer graft-polymerized with monomers such as methyl methacrylate, styrene and acrylonitrile is mixed with thermoplastic resin to improve impact resistance. A method of imparting properties has been proposed (Japanese Patent Laid-Open No. 57-102).
940, JP-A-60-235854, JP-A-58-152039).

Conventionally, a bloated rubber graft copolymer has been used for improving impact resistance. As a bloated technology for the rubber, a bloated technology using an electrolyte, a polymer organic acid latex, an acid or the like is used. Has already been reported.

[0004] Above all, a lot of researches have been conducted on the enlargement technique using an acid, and by adding an acid to the rubber-like polymer latex to lower the latex pH, the latex particles are agglomerated and enlarged. It is well known to carry out the treatment and then add a basic substance to make the pH of the system alkaline to stabilize the latex.

At this time, the problem is how to maintain the stability of the latex at the time of coagulation and enlargement and obtain the enlarged latex without generating the generation of rubber lumps.

As a method for improving this point, a step of adding acid to the rubber-like polymer latex to make it larger than pH 7.0 and then enlarging it, and then adding a basic substance at 40 ° C. or higher and stirring strength at the time of graft polymerization. Method (Japanese Patent Publication No. 55-19246) and an acid is added to a rubber-like latex using a fatty acid soap, and when it is enlarged at a pH of 4.0 or less, the acid is added in a shower or mist state. A method (Japanese Patent Publication No. 2-9601) has been proposed.

Japanese Patent Publication No. 55-19246 discloses that the stirring strength is less than half that of the graft polymerization, but there is no description that defines the stirring strength during the graft polymerization, and the stirring strength of Stirring strength is unknown. Further, 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 the latex having a low solid content concentration in which rubber lumps are hard to occur. High productivity cannot be obtained.

In the method described in Japanese Patent Publication No. 2-9601, a latex having a low solid content is similarly prepared (the solid content of the enlarged latex shown in the examples is 21 to 23% by weight).
However, this method does not provide high productivity.

Further, in this method, the acid and the latex are mixed by allowing the molecules to diffuse without stirring, so that uniform aggregation hardly occurs, and even if the uniform aggregation occurs, it takes a considerable time. , Productivity is poor.

As an example of obtaining an enlarged latex having a high solid content, a method of continuously supplying the latex and the acid to a flow-through tube type device in the coagulation step of adding the acid to the 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 that is acidic and its surface activity is reduced, and an excess amount of acid is added, and then a polymer latex is further added to enlarge the polymer latex (Japanese Patent Publication No. 7- No. 21012) has been proposed.

In Japanese Patent Publication No. 7-21014,
Although the enlarged solid latex having a high solid content concentration of 29 to 34.8% by weight of solid content is obtained (Examples 1 to 3), a flow-through tube type apparatus is required in addition to the stirring tank, and the equipment cost is high. It is not economical.

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

However, this is because the latex before bloat is a latex having an average particle diameter of 0.185 μ, and it takes a very long polymerization time to obtain a latex having such a large particle diameter (26 hours in the example). ), There is a problem in productivity before it becomes bloated. The 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, and enlarges a small particle latex that can be polymerized in a relatively short time. It is a meaningful means.

In other methods, a method for increasing the stability of the latex is required, and unexpanded particles remain in the expanded latex, resulting in a broad particle size distribution and insufficient impact resistance improvement. .

[0015]

DISCLOSURE OF THE INVENTION As a result of intensive studies for solving the above problems, the present inventors have found that the diene polymer rubber latex is enlarged by agglomeration mainly by Brown agglomeration. A rubber latex coagulation and enlargement method for obtaining an enlarged diene polymer rubber latex having a high solid content without producing a rubber lump by carrying out the method, and a graft copolymer obtained from the enlarged diene polymer rubber latex The inventors have found that a thermoplastic resin composition using the graft copolymer and the graft copolymer thereof has excellent impact resistance and arrived at the present invention.

That is, the gist of the present invention is that
A diene polymer rubber latex obtained by emulsion polymerization is coagulated and enlarged to obtain an enlarged diene polymer rubber latex (A). In the cohesive and enlarged method of a diene polymer rubber latex, brown coagulation is mainly used. A method for enlarging a diene-based polymer rubber latex, which comprises enlarging by coagulation, a graft copolymer (B) of the enlarged diene-based polymer rubber latex (A) obtained by the method, and a graft thereof It is a thermoplastic resin composition containing a copolymer (B).

[0017]

BEST MODE FOR CARRYING OUT THE INVENTION Brown agglomeration in the present invention means that latex particles collide and agglomerate by performing Brownian motion. Usually, latex agglomeration mainly occurs due to Brownian agglomeration and shear agglomeration, but shear agglomeration is a phenomenon in which latex particles move and collide due to a flow caused by adding shear such as stirring to agglomerate. is there.

The inventors of the present invention have found that, when the coagulation and enlargement of the rubber latex is increased, the larger the contribution of the brown coagulation is, the less the generation of rubber lumps is and the more stable the enlarged latex is obtained. In order to make the contribution of Brown's agglomeration large, the shear applied to the latex should be low, and complete Brown's agglomeration can be achieved without shearing. Complete brown agglomeration can completely suppress the generation of rubber lumps, but on the other hand, it takes a lot of time to mix the latex and the aggregating agent without shearing, which leads to a decrease in productivity. become.

Therefore, the object of the present invention can be achieved by applying a gentle shearing to the extent that a rubber lump is not generated to promote the coagulation and enlargement while promoting the mixing of the coagulant.

Further, since the enlargement based on the chemical stability can be performed by performing the enlargement of aggregation by the method mainly based on Brownian aggregation, the particles having a relatively uniform particle size can be obtained as compared with the shear aggregation due to the mechanical factor of collision and aggregation. By taking a particle size distribution having a diameter, it was found that the unenlarged particles are very small.

That is, the greatest feature of the present invention is to carry out the coagulation and enlargement 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 a conventional emulsion polymerization,
Examples thereof include polybutadiene and a latex of a copolymer of 50% by weight or more of butadiene and a monomer copolymerizable with butadiene.

As the monomer copolymerizable with butadiene, aromatic vinyl type monomers such as styrene and α-methylstyrene, (meth) acrylic acid alkyl esters such as methyl methacrylate and n-butyl acrylate are used. Examples thereof include unsaturated monomers such as acrylonitrile and unsaturated nitrile monomers.

Further, a crosslinkable monomer such as divinylbenzene, ethylene glycol dimethacrylate, 1,3 butanediol diacrylate, allyl methacrylate or the like can be used in combination.

The monomer copolymerizable with butadiene and the crosslinkable monomer may be used alone or as a mixture, and the diene polymer may be used as a t-polymer, if necessary at the time of polymerization.
Dodecyl mercaptan, n-octyl mercaptan, α
Chain transfer agents such as methyl styrene dimer can also be used.

The number average particle size 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 size of the diene polymer rubber latex exceeds 0.15 μm, it does not hinder the aggregation process at all, but the number average particle size of 0.15 is obtained by emulsion polymerization.
If it is attempted to obtain a diene-based polymer rubber latex having a particle size of more than μm, it requires long-time polymerization, which lowers the productivity during emulsion polymerization, and the effect of improving the productivity in the aggregating step becomes low.

Further, since the solid content concentration of the diene polymer rubber latex after the enlargement is preferably 30% by weight or more, the solid content concentration is lowered when the acid aqueous solution is added and neutralized. Considering this, the diene polymer rubber latex solid content concentration is preferably 35% by weight or more,
More preferably, it is 40% by weight or more.

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

When 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 in a enlargement method mainly comprising Brownian agglomeration.

In the method of the present invention, which mainly uses Brownian agglomeration, the equipment and process are not particularly limited, but, for example, in a stirring tank, stirring can be performed by the number of revolutions (N
s) It is preferable to carry out the following.

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

Propeller blades: k = 0.60, N0 = 450, D0 = 60 Swept blades: k = 0.46, N0 = 300, D0 = 60 Paddle blades: k = 0.50, N0 = 270, D0 = 70 Large plate blade: k = 0.55, N0 = 200, D0 = 80 According to the above formula (1), depending on the diameter of the stirring blade and the type of the stirring blade, the limit rotational speed (Ns: rpm) during the aggregating step is determined. You can ask. When stirring is performed at a rotation speed of Ns (rpm) or more, a rubber lump may be generated, which may lead to a decrease in productivity.

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

The retreating blade mentioned above is a stirring blade represented by the three-way retreating blade shown in FIGS. 3 and 4, and the shape is not limited, but the number of blades is 3 to 4 and the retreating length (see FIG. Four
The length indicated by 5 in the figure is 0.05 to 0.3 times the blade diameter (twice the length indicated by 6 in FIG. 4) and the blade tip height (shown by 4 in FIG. 3). 2) of the blade diameter (the length indicated by 6 in Fig. 4)
0.01 to 0.2 times, and the blade height (the length indicated by 7 in FIG. 5) is 0.1 to the blade diameter (twice the length indicated by 6 in FIG. 4). It is preferably 0.5 times.

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

Further, the above-mentioned large plate-shaped blade means the full-zone blade shown in FIGS. 8 and 9 (manufactured by Shinko Pantech Co., Ltd.).
Blades represented by, that is, the rotating shaft 11 close to the bottom of the tank.
The lowermost blade 13 of the radial flow type installed in the
Attached to the upper and lower blades adjacent to each other in the direction of rotation with respect to the lower blades vertically adjacent to each other (up to one stage), and has upper blades 12 of a radial flow type, and vertically adjacent blades face each other. A blade in which the end portions in the radial direction of the blade end are arranged so as to overlap each other in the vertical direction, or FIG.
The blade represented by Maxblend (manufactured by Sumitomo Heavy Industries, Ltd.), that is, the paddle 16 for stirring the bottom of the tank is attached to the lower part of the rotary shaft 15, and the rotary shaft 1 is provided above the rotary shaft 15.
5 is a blade equipped with a lattice blade 19 including a horizontal member 17 extending horizontally from the horizontal member 5 and a member 18 extending in a direction perpendicular to the horizontal member.

Size of the stirring blade (14 in FIGS. 8 and 9;
10) of FIG. 10 can be set to an arbitrary size according to the size of the stirring tank, but preferably 0.3 times the diameter of the stirring tank.
A 0.8x wing is preferred.

Further, in order to promote the mixing of the coagulant aqueous solution, a baffle plate can be installed, eccentric stirring, etc. can be carried out within a range where rubber lumps are not formed.

When the baffle plates are installed, it is preferable that the number of baffle plates is 4 or less and that the lower end of each baffle plate is located above the upper end of the stirring blade. When performing eccentric stirring, the horizontal distance from the center of the stirring tank to the center of the stirring shaft is preferably 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 it is preferably as short as possible within the range where the aqueous coagulant solution is completely mixed, preferably 60 minutes or less, more preferably 20 minutes. It is the following.

In the present invention, the diene polymer latex is emulsion-polymerized by using fatty acid soap as an emulsifier, and after addition of an emulsifier which is acidic and has a good surface-active ability in the coagulation and enlargement process. It is preferable to add a coagulant to adjust the pH to 5 or less, and then neutralize with a basic substance to increase the coagulation and enlargement of the diene polymer rubber latex.

As the fatty acid soap used as an emulsifier,
Although not particularly limited, for example, mixed fatty acid sodium,
Examples thereof include mixed fatty acid potassium, sodium oleate, potassium oleate, sodium stearate, potassium stearate, and disproportionated potassium rosinate. These fatty acid soaps can be used alone or in combination.

The amount of the fatty acid soap added may be an amount necessary for maintaining the stability of the latex during emulsion polymerization, and is not particularly limited, but usually 100 parts of the diene polymer monomer is used.
It is 0.5 to 5 parts by weight with respect to parts by weight.

The emulsifier having an acidic and good surface-active ability used in the coagulation and enlargement process is not particularly limited, but is preferably an emulsifier having a sulfonic acid group and a salt of an alkali metal, such as sodium alkylbenzene sulfonate, Polyoxyethylene alkyl ether sulfite
, Sodium alkyldiphenyl ether disulfonate, sodium alkyl naphthalene sulfonate, sodium dialkyl sulfosuccinate, etc. may be used alone or in combination.

The addition amount of the emulsifier which is acidic and has a good surface activity is 0.01 to 0.5 part by weight, preferably 0.1 to 100 parts by weight of the solid content of the diene polymer latex. ~ 0.3 parts by weight.

When the amount of the emulsifier added 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, if the addition amount exceeds 0.5 parts by weight, the effect of enlarging the diene polymer rubber latex particles due to the addition of the coagulant will be reduced.

The time of adding the emulsifier which is acidic and does not reduce 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 aggregating agent. Then, this flocculant is added so that the pH of the system becomes 5 or less. PH of system is 5
If the coagulant aqueous solution is added only in an amount that does not
It is not possible to obtain a sufficient enlargement effect. As the acid of the coagulant (acid) aqueous solution, inorganic acids such as sulfuric acid, hydrochloric acid and phosphoric acid and organic acids such as acetic acid, formic acid, lactic acid, acrylic acid and methacrylic acid are used, but are not particularly limited.

From the viewpoint of productivity, it is desirable that the concentration of the aqueous solution of the coagulant is as high as possible within the range where rubber lumps are not generated at the time of addition. It must be set according to the type. For example, the concentration in the case of aqueous sulfuric acid solution is 0.
It 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 flocculant solution is not particularly limited, but it is preferable to slowly add the aqueous acid solution while stirring the diene polymer rubber latex in a stirring tank, and preferably, the diene polymer rubber latex is immersed in the latex solution alone or A method of gently injecting from a plurality of nozzles, a method of gently injecting from a drainage port of a stirring vessel 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, aqueous solutions of sodium hydroxide and potassium hydroxide are more preferable. . Even if the concentration of the aqueous solution of the basic substance is high, there is no problem that a rubber lump is generated. However, when the concentration is low, the liquid amount becomes large and the solid content of the final polymer latex decreases, which is not preferable. The aqueous solution concentration of the basic substance is usually preferably 5 to 60% by weight.

The temperature of the system for carrying out the aggregating step in the present invention is not particularly limited, but it is preferably carried out at 10 ° C to 60 ° C.

In the present invention, the average particle diameter of the enlarged diene polymer rubber latex (A) is adjusted to 7 after the enlargement by changing the acid amount and the addition amount of an emulsifier having acidic and good surface activity. It can be controlled as desired by changing it in the following range, preferably in the range of 5 or less, but when it is used as an impact modifier for a thermoplastic resin, the number average particle diameter is 0.15 μm. ~ 0.5 μm and
Particles having a particle size of 0.15 μm or less are preferably 10% by weight or less.

The graft copolymer (B) of the present invention is obtained by adding an aromatic vinyl monomer, (meta) to a bloated diene polymer rubber latex (A) bloated by coagulation mainly based on Brown coagulation. ) One-step or multi-step graft polymerization of at least one monomer selected from the group consisting of acrylic acid ester-based monomers, unsaturated nitrile-based monomers and monomers copolymerizable therewith. is there.

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. When it is less than 55% by weight, impact resistance is insufficiently expressed, and when it exceeds 85% by weight, other excellent properties of the thermoplastic resin (C) tend to be lost, which is not preferable.

Examples of the aromatic vinyl-based monomer to be graft-polymerized include styrene, α-methylstyrene, various halogen-substituted and alkyl-substituted styrenes, and the (meth) acrylic acid ester-based monomer to be graft-polymerized is:
Methacrylic acid esters such as methyl methacrylate, ethyl methacrylate, propyl methacrylate, glycidyl methacrylate, methyl acrylate, ethyl acrylate,
Acrylic esters such as butyl acrylate and glycidyl acrylate are graft-polymerized as unsaturated nitrile-based monomers, acrylonitrile, methacrylonitrile and the like are graft-polymerized as monomers copolymerizable with them. Is an aromatic polyfunctional vinyl compound such as divinylbenzene and divinyltoluene, dimethacrylate of polyhydric alcohol such as ethylene glycol dimethacrylate and 1,3 butanediol diacrylate, polymethacrylate such as trimethacrylic acid ester and triacrylic acid ester. Meta)
Examples thereof include acrylic acid esters, carboxylic acid allyl esters such as 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 at the same time,
In order to increase the compatibility, methyl methacrylate is used as a monomer to be graft-polymerized, but a vinyl-based monomer copolymerizable with this may be used in combination if necessary.

Graft polymerization is preferably carried out in three stages, and the first stage is mainly composed of methyl methacrylate and is used for improving impact resistance and compatibility with vinyl chloride resin, and the second stage is used. Is used as the main component to increase the fluidity of the graft copolymer, and the third step is used to increase the surface gloss of the resulting thermoplastic resin composition by using methyl methacrylate as the main component.

The monomers used in these graft polymerizations can be used alone or in combination.

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

The obtained graft copolymer (B) latex is added with or without addition of an appropriate antioxidant or additive, or an acid such as sulfuric acid, hydrochloric acid or phosphoric acid, calcium chloride,
A coagulant such as a salt such as sodium chloride is appropriately used for coagulation, heat treatment for solidification, dehydration, washing, and drying to obtain a powdery graft copolymer (B).

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

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

The thermoplastic resin (C) is not particularly limited, but when a polyvinyl chloride resin is used, the polyvinyl chloride resin may be a chlorine group-containing resin such as polyvinyl chloride or chlorinated vinyl chloride, or 70% by weight. % Vinyl chloride and a copolymer of 30% by weight or less of another monomer copolymerizable with vinyl chloride can be used. Other copolymerizable monomers include vinyl bromide, vinylidene chloride, vinyl acetate,
Acrylic acid, methacrylic acid, ethylene and the like can be mentioned.

The thermoplastic resin composition of the present invention is prepared by mixing the above-mentioned graft copolymer (B) and thermoplastic resin (C) in powder form with a ribbon blender, a Henschel mixer, etc., and using a known kneader, extruder or the like. Formed by. The thermoplastic resin (C) may be mixed with the graft copolymer (B), and the mixture may be powdered through steps such as coagulation, solidification, washing and drying. When mixing by these various methods, known stabilizers, plasticizers, processing aids, colorants 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 the scope of the invention is not exceeded. In addition, "part" and "%" in Examples and Comparative Examples mean "part 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 size and particle size distribution The number-average particle size was measured by using a 6-inch roll, kneading at 185 ° C., press molding at 50 Kg / cm ² , and 185 ° C., and then image analysis using TEM. Performed and measured. The particle size distribution was expressed as a weight percentage of unenlarged small particles.

Scale (bulk) after enlargement The amount of scale (bulk) after enlargement was expressed in% by weight with respect to the amount of charged monomers after drying the generated scale.

Izod impact 6-inch roll kneading at 185 ° C., 50 kg /
cm ² , after press molding at 185 ° C, 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, Δ−− Fogging, × −− Matte (Examples and Comparative Examples) (a) Polymerization of diene polymer rubber latex (ac) [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 Desorption Ionized water 150 parts Each charging component having the above composition was charged in a pressure resistant autoclave and reacted at 60 ° C. for 8 hours with stirring to produce a diene polymer rubber latex.

The number average particle diameter of the obtained diene polymer rubber latex was 0.09 μm, the solid content concentration was 40%, and p
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 Parts Dextrose 1 part Potassium beef tartrate 1.5 parts Deionized water 180 parts The charge components of the above composition were charged in a pressure resistant autoclave and reacted at 60 ° C. for 8 hours with stirring to produce a diene-based compound. A polymer rubber latex was produced.

The diene polymer rubber latex obtained had a number average particle diameter of 0.09 μm, a solid content concentration of 36%, and a p
H was 9.1.

[C] 1,3 butadiene 100 parts t-dodecyl mercaptan 0.6 parts diisopropylbenzene hydroperoxide 0.4 parts soda pyrophosphate 1.5 parts ferrous sulfate 0.02 parts dextroze 1 part Sodium beeflate 1.5 parts Deionized water 170 parts Each of the charged components of 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. did.

The number average particle diameter of the obtained diene polymer rubber latex was 0.08 μm, the solid content concentration was 37%, and p
H was 9.1.

(B) Preparation of stirring tank [Condition-1] 65 L stirring tank (inner diameter 400 mm, height 65)
0 mm, SUS, no baffle), the number of blades on the stirring blade is 3, the angle of the blade root (the angle indicated by 1 in FIG. 1) and the maximum inclination angle of the blade (the angle indicated by 2 in FIG. 1) are A propeller blade having a blade diameter of 180 mm and a blade angle of 45 ° was also installed so that the center of the stirring blade was located 45 mm from the bottom on the central axis of the stirring tank.

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

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

[Condition-4] 2.5 L stirring tank (inner diameter 135
mm, height 200 mm, glass, without baffle), the number of blades on the stirring blade is 3, and the angle of the blade root (Fig. 1).
1) and the maximum inclination angle of the blade (Fig. 1).
The angle indicated by 2) is 45 ° in all cases, and the wing diameter is 60.
Using a propeller blade of mm, the stirring blade was installed so that the center of the stirring blade was 15 mm from the bottom on the central axis of the stirring tank.

In [Condition-5] and [Condition-4], the number of stirring blades is 6, the inclination angle is 0 ° (the angle shown by 8 in FIG. 6), and the blade height is 10 mm (shown by 9 in FIG. 6). Length), except that the paddle blade has a blade diameter of 70 mm.
4].

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

[Condition-7] In [Condition-4], the number of stirring blades was four, the inclination angle was 45 ° (the angle shown by 8 in FIG. 6), and the blade height was 10 mm (shown by 9 in FIG. 6). Length), except that the paddle blade has a blade diameter of 70 mm.
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 blades have two blades with a phase difference of 45 °. The conditions were the same as [Condition-4], except that the height of the blade was 100 mm.

[Condition-9] In [Condition-4], a paddle having a diameter of 80 mm and a height of 40 mm for agitating the bottom of the tank was attached to the lower part of the rotary shaft, and the upper part of the rotary shaft (positions 25 mm and 50 mm above the upper end of the paddle). ) From the rotary shaft of the upper horizontal member having a diameter of 80 mm and a height of 10 mm and extending horizontally from the rotary shaft to the rotary shaft by 40 m each in both wing directions.
The conditions were the same as [Condition-4] except that a MaxBlend blade equipped with a lattice blade consisting of four members having a width of 10 mm and a height of 50 mm extending vertically downward from the positions of m and 80 mm was used.

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

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

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 10 mm was set in the same direction (circumferential direction) as the rotating direction of the stirring blade, and the aqueous acid solution was supplied from the L-shaped nozzle. The amount was 100 parts of diene polymer rubber latex) was added to the latex over 7 minutes. After that, the stirring was continued for 10 minutes and then maintained. The pH of the system is shown in Table 1.

Then, an alkaline aqueous solution (concentration and amount shown in Table 1, concentration is wt%, amount is the number of parts relative to 100 parts of diene polymer rubber latex) was added to complete the enlargement operation. Table 1 shows the solid content concentration, number average particle size, pH, and amount of rubber lumps generated (scale) of the obtained cohesive 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).
0 g and 1 of the emulsifier which is acidic and has good surface activity
A 0% aqueous solution is shown in Table 1 (in Table 1, the number of parts of emulsifier is based on 100 parts of diene polymer rubber latex).
It was added and gently stirred well.

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 was set in the same direction (circumferential direction) as the rotating direction of the stirring blade, and the aqueous acid solution was supplied from the L-shaped nozzle (concentration and amount are shown in Table 1, concentration is% by weight). The amount was 100 parts of diene polymer rubber latex) was added to the latex over 7 minutes. After that, the stirring was continued for 10 minutes and then maintained. The system pH is shown in Table 1.
It was shown to.

Then, an alkaline aqueous solution (concentration and amount shown in Table 1, concentration is weight%, amount is the number of parts relative to 100 parts of diene polymer rubber latex) was added to complete the enlargement operation. Table 1 shows the solid content concentration, number average particle size, pH, and amount of rubber lumps generated (scale) of the obtained cohesive and enlarged diene polymer rubber latex.

[Condition 10] The diene polymer rubber latex 27k obtained in (a) was added to the stirring tank prepared in (b).
10 g of an emulsifier having good surface activity in g and acidity
% Aqueous solution was added as shown in Table 1 (in Table 1, the number of parts of emulsifier to 100 parts of diene polymer rubber latex was added), and the mixture was gently 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 was set in the same direction (circumferential direction) as the rotating direction of the stirring blade, and the aqueous acid solution was supplied from the L-shaped nozzle. The amount was 1/4 of 100 parts of diene polymer rubber latex) was added to the latex over 2 minutes. Then, 1/4 of an alkaline aqueous solution (concentration and amount are shown in Table 1, concentration is wt%, amount is the number of parts relative to 100 parts of diene polymer rubber latex) was added and stirred for 2 minutes. The acid addition and the alkali addition were repeated 4 times to complete the enlargement operation.

Table 1 shows the solid content concentration, number average particle size, pH, and rubber block generation amount (scale) of the obtained cohesive and enlarged diene polymer rubber latex.

[0099]

[Table 1]

(D) Synthesis of Graft Copolymer (B) The above flocculated and enlarged diene polymer rubber latex was charged into a flask in an amount (as solid content) described in Table 2,
After purging with nitrogen, 1.5 parts of the same emulsifier used for rubber polymerization was added as a 7% aqueous solution to stabilize, and then 0.6 part of Rongalit was added to maintain the internal temperature at 70 ° C.
When the total amount of the monomer and monomer mixture in the first stage of graft and the monomer and monomer or mixture of monomers in the first stage of graft is 100 parts, the amount is 0. 2 parts of cumene hydroperoxide (CH
The mixture to which P) was added was added dropwise over 1 hour and then kept for 1 hour.

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

Then, in the presence of the polymer obtained in the first and second stages, the amount of the monomer or monomer in the third stage of graft shown in Table 2 as the third stage or When the total amount of the monomer mixture and the monomer or monomer mixture in the third stage of the graft is 100 parts, the ratio is 0.
The mixture to which 2 parts of CHP was added was added dropwise over 1 hour and then kept for 1 hour to terminate the polymerization.

Graft Copolymer Latex 10 Obtained
0 parts by weight of 1,4-dihydro 2,6-dimethyl 3,
After adding 0.5 parts of 5-dicarbododecyloxy pyridine (DHP), 2 parts of a 0.2% sulfuric acid aqueous solution was added to 100 parts by weight of the graft copolymer in a pure content to cause coagulation, and completely. When no coagulation was carried out, a 5% sodium chloride aqueous solution was added as necessary, and the mixture was heat-treated and solidified at 90 ° C. Thereafter, the coagulated product was washed with warm water and further dried to obtain a graft copolymer powder.

(E) Preparation of 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. (Registered trademark) P-550 (Mitsubishi Rayon Co., Ltd.)
2 parts), Metabrene (registered trademark) P-710 (manufactured by Mitsubishi Rayon Co., Ltd.), and each component of the graft copolymer resin (B) powder obtained in (3) above with a Henschel mixer. The mixture was mixed for 10 minutes until the temperature reached to obtain a polyvinyl chloride resin composition.

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

[0106]

[Table 2]

[0107]

EFFECTS OF THE INVENTION According to the coagulation and enlargement method of the present invention, a rubber latex is produced in a conventional stirring tank with almost no formation of a rubber lump, and an enlarged rubber latex having a desired particle size is produced with good productivity. It is possible to obtain a graft copolymer by carrying out graft polymerization of the enlarged rubber latex, and by using the graft copolymer, a thermoplastic resin composition having excellent impact resistance can be obtained. It has become possible to obtain.

[Brief description of 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 cross-sectional view of a swept wing used in the present invention.

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

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

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

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

FIG. 10 is a side view of a large plate blade (Maxblend 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 inclination angle 9 blade height 10 blade diameter 11 rotating shaft 12 upper stage Blade 13 Bottom blade 14 Blade diameter 15 Rotation axis 16 Paddle 17 Horizontal member 18 Member extending at a right angle from horizontal member 19 Lattice blade 20 Blade diameter

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Akira Nakata 20-1 Miyukicho, Otake City, Hiroshima Prefecture Mitsubishi Rayon Co., Ltd. Otake Office

Claims (5)

[Claims] 1. A coagulating and enlarging method for obtaining an enlarged diene polymer rubber latex (A) by coagulating and enlarging a diene polymer rubber latex obtained by emulsion polymerization. A method for coagulating and enlarging a diene polymer rubber latex, which comprises enlarging. 2. The method for coagulating and enlarging a diene polymer rubber latex according to claim 1, wherein the enlarged diene polymer rubber latex (A) has a solid content concentration of 30% by weight or more. 3. The diene polymer rubber latex according to claim 1, wherein the Brownian agglomeration is performed in a stirring tank at a stirring rotation speed of not more than the rotation speed (Ns) shown in the following formula (1). Method for coagulating and enlarging. Ns = (D0 / Ds) k × N0 --- (1) Formula Ds: Stirring blade diameter (mm) Ns: Limit stirring speed (rpm) in coagulation and enlargement process k, D0, and N0 are determined by the shape of the stirring blade. constant. Propeller blade: k = 0.60, N0 = 450, D0 = 60 Swept blade: k = 0.46, N0 = 300, D0 = 60 Paddle blade: k = 0.50, N0 = 270, D0 = 70 Large plate Wing: k = 0.55, N0 = 200, D0 = 80 4. A number average particle diameter of 0.15 to 0.5 obtained by agglomeration and enlargement of a diene polymer rubber latex obtained by emulsion polymerization by a method mainly composed of Brown agglomeration.
A thickened diene polymer rubber latex having a size of μm, comprising an aromatic vinyl monomer, a (meth) acrylic acid ester monomer, an unsaturated nitrile monomer, and a monomer copolymerizable therewith. A graft copolymer (B) in which at least one monomer selected from the group is graft polymerized in one stage or in multiple stages. 5. A thermoplastic resin composition comprising a thermoplastic resin (C) and the graft copolymer (B) according to claim 4.