JP3537954B2 - Manufacturing method of rubber reinforced styrenic resin - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

[0001] The present invention relates to a method for producing a rubber-reinforced styrene resin.

[0002]

2. Description of the Related Art Conventionally, as a method for producing a rubber-reinforced styrene resin, for example, (1) a method in which a vinyl monomer is polymerized in the presence of a rubbery polymer and then mixed with the styrene resin, A method of mixing a styrene-based resin with a graft copolymer obtained by graft-polymerizing a vinyl-based monomer onto a rubber-like polymer is known.

[0003] However, the method (1) described above has a difficulty in responding to diversified demands for multi-kind production. In the production method (2), the graft copolymer is often in the form of a powder because it is produced by an emulsion polymerization method. However, the styrene-based resin mixed therewith is used in a bulk polymerization method, a solution polymerization method, Since it is produced by a suspension polymerization method or the like, it is in the form of pellets, granules, or beads. The above-mentioned graft copolymer powder often caused blocking during storage and transportation. As a result, there are problems that the graft copolymer powder cannot be measured smoothly and that the powder and the styrene-based resin cannot be mixed uniformly when mixed. Also, particularly recently, when mixing the styrene resin having the above-mentioned shape with the powder of the graft copolymer, the blocking resistance is increased due to an increase in the size of an automatic weighing machine and a production line for the graft copolymer. The demand for improvement is increasing.

On the other hand, for the purpose of improving the impact resistance and the like of a polyvinyl chloride resin, there have been many attempts to improve the powder properties (such as the above-described blocking resistance) of the powdery graft copolymer used in the resin. There are suggestions. For example, JP-A-58-1742 discloses a method in which a methyl methacrylate-based copolymer is added to a slurry containing particles of a graft copolymer. JP-A-58-48584 discloses a method in which a rubber is added to a graft copolymer. A method of adding a graft copolymer having a small content is disclosed in JP-A-7-3106, and a method of adding a methyl methacrylate-based copolymer cross-linked to the graft copolymer is disclosed in JP-A-64-26644. In the publication, all methods for adding a lubricant to the graft copolymer are described.

[0005] However, the methods described in these publications are directed to polyvinyl chloride resins, and simply mixing them with a styrene-based resin, such as those required for rubber-reinforced styrene-based resins, such as, There is a problem that a rubber-reinforced styrene-based resin having satisfactory properties such as impact properties, rigidity, heat deformation resistance, and thermal stability and molding processability cannot be obtained.

[0006] After improving the powder properties such as blocking resistance of the conventional graft copolymer containing a rubbery polymer as described above, it is further mixed with a styrene-based resin to obtain a desired molding. At present, no production method has been found for obtaining a rubber-reinforced styrenic resin which can sufficiently satisfy the physical properties.

[0007]

DISCLOSURE OF THE INVENTION The present inventors have conducted intensive studies in view of the above problems, and as a result, have found that the particles of a graft copolymer having a specific composition and the particles of a lubricant and / or the copolymer having a specific composition have been obtained. The particles and the aqueous dispersion or slurry state, that is, an impact resistance improver obtained by mixing in a wet state is particularly excellent in the blocking resistance, and is mixed with a styrene-based resin, particularly a styrene-based resin in a certain range. Thereby, it has been found that the physical properties of the molded article such as the impact resistance can be significantly improved.

That is, an object of the present invention is to use a graft copolymer having excellent powder properties such as blocking resistance,
Another object of the present invention is to provide a method for producing a rubber-reinforced styrene-based resin having excellent physical properties of a molded article such as the impact resistance.

[0009]

According to the present invention, a rubbery polymer is added to 40 to 85 parts by weight in a weight ratio of 10 to 40/90 to 60.
15 to 60 parts by weight of a vinyl monomer mixture (1) comprising a vinyl cyanide monomer and an aromatic vinyl monomer
The total amount of the rubbery polymer and the vinyl monomer mixture (1) is 1
Aqueous slurry containing 0.01 to 10 parts by weight of lubricant (a-II) particles in a slurry containing 100 parts by weight of particles of the graft copolymer (a-I) obtained by graft polymerization of Dispersion and / or vinyl cyanide monomer 0
-40% by weight, 0 to 80% by weight of an aromatic vinyl monomer, 0 to 100% by weight of an acrylate monomer, and 0 to 100% by weight of a methacrylate ester monomer (however, these four types Aqueous solution containing 0.1 to 25 parts by weight of particles of a copolymer (a-III) obtained by copolymerizing a vinyl monomer mixture (2) containing The present invention relates to a method for producing a rubber-reinforced styrene resin in which a styrene resin is mixed with an impact resistance improver obtained by heat-treating and drying a particle mixture obtained by mixing a dispersion and aggregating the particles.

[0010]

BEST MODE FOR CARRYING OUT THE INVENTION The process for producing the rubber-reinforced styrene resin of the present invention is carried out by preparing a graft copolymer (a-I) particle and a lubricant (a-II) particle having a specific composition and / or a copolymer having a specific composition. The greatest feature is to use an impact modifier obtained by mixing the particles of the coalesced particles (a-III) with the particles in the form of a slurry or an aqueous dispersion in a wet state, and the lubricant (a-II)
And the particles of the copolymer (a-III) having a specific composition use at least one of these.

In the present specification, the term "aqueous dispersion" refers to, for example, an aqueous dispersion obtained by emulsion polymerization of the vinyl monomer mixture (1) or (2); And the like. The term "slurry" refers to a substance obtained by agglomerating fine particles in an aqueous dispersion to some extent by, for example, adding a coagulant or the like to the aqueous dispersion.

In the present invention, it is not clear, but by using particles of the lubricant (a-II), the surface of the graft copolymer (a-I) in the form of slurry can be used as the lubricant (a-II).
It is believed that an impact modifier having excellent powder properties, especially excellent blocking resistance, can be obtained. In addition, by using the particles of the copolymer (a-III) having a specific composition, the surface of the graft copolymer (a-I) in a slurry state has a specific composition of the copolymer (a-III).
, It is considered to be particularly excellent in blocking resistance as described above.

In the present invention, the lubricant (a-II)
And at least one kind of particles of the copolymer (a-III) having a specific composition, and the particles of the graft copolymer (a-I) are mixed with the particles in the wet state. As a result of the particles being very homogeneously mixed,
Since it is uniformly dispersed in the styrene resin described later, and the rubbery polymer in the particles of the graft copolymer (a-I) is also uniformly dispersed, the molded article has excellent physical properties, particularly excellent impact resistance. It is considered that a rubber-reinforced styrene-based resin is obtained.

The graft copolymer (a-
I) is obtained by graft-polymerizing a vinyl monomer mixture (1) composed of a vinyl cyanide monomer and an aromatic vinyl monomer in order to make the rubbery polymer compatible with a styrene resin described later. Can be obtained. In the present invention, the graft copolymer (a-I) includes an ungrafted copolymer of the vinyl monomer mixture (1) not grafted on the rubbery polymer.

The above-mentioned rubbery polymer is a polymer having a rubbery state which is generally used at room temperature and used for obtaining impact resistance. Examples thereof include polybutadiene, styrene-butadiene copolymer, and butyl acrylate-butadiene. Diene polymers such as copolymers; acrylic polymers such as polybutyl acrylate; olefin polymers such as ethylene-propylene copolymer and ethylene-propylene-diene copolymer; and the like. However, polybutadiene and polybutyl acrylate are particularly preferred from the viewpoint of the properties of the molded article.

The rubbery polymer may be, for example, an aqueous dispersion obtained by an ordinary method such as an emulsion polymerization method, and its glass transition point is -20 ° C. or lower from the viewpoint of obtaining impact resistance. , And preferably -50 ° C or lower. The weight average particle diameter of the rubber-like polymer particles may be in the range of 0.05 to 1 μm.
If it is less than 05 μm, the impact resistance tends to decrease, and 1 μm
If it exceeds m, rigidity, impact resistance, and surface gloss tend to decrease. Further, the gel content of the rubber-like polymer particles (after immersion in toluene for 24 hours) may be in the range of 10 to 95% (wt%, the same applies hereinafter), and if it is less than 10%, the surface gloss tends to decrease. If it exceeds 95%, the impact resistance tends to decrease.

The vinyl monomer mixture (1) is used for obtaining compatibility with the styrene resin. Among them, examples of the vinyl cyanide monomer include acrylonitrile and methacrylonitrile.
Acrylonitrile is preferred from the viewpoint of the properties of the molded article. The aromatic vinyl monomer is, for example, styrene, α
-Methylstyrene, the substituted α-methylstyrene and the like, and styrene is particularly preferred from the viewpoint of compatibility with the styrene resin. In the present invention, monomers that can be copolymerized with these vinyl monomers as necessary, for example, methyl acrylate, ethyl acrylate, alkyl acrylates such as butyl acrylate, methyl methacrylate, ethyl methacrylate And methacrylic acid alkyl esters such as butyl methacrylate can also be used. Of these, methyl methacrylate is preferred from the viewpoint of the properties of the molded article.

The composition of the vinyl monomer mixture (1) is as follows:
It is preferable that the weight ratio of the vinyl cyanide monomer to the aromatic vinyl monomer is 10 to 40/90 to 60, and if the amount of the aromatic vinyl monomer is less than 60, the moldability tends to decrease. When it exceeds 90, impact resistance and chemical resistance tend to decrease. When using a monomer which can be co-polymerized with the vinyl monomer as needed, the amount of these monomers is 30% by weight based on the weight of the vinyl monomer mixture (1).
The following is preferred.

The graft copolymer (a-I) is obtained by adding 15 to 60 parts of the vinyl monomer mixture (1) having the above composition to 40 to 85 parts (parts by weight, hereinafter the same) of the rubbery polymer. , The total amount of the rubber-like polymer and the vinyl monomer mixture (1) is 100 parts).
In particular, if the rubber-like polymer is less than 40 parts, the impact resistance tends to decrease, and the mixing ratio when mixed with the styrene-based resin described later tends to be restricted. The compatibility, impact resistance, rigidity, and surface gloss tend to decrease, and the surface of the molded article tends to be uneven.

Examples of the method for synthesizing the graft copolymer (a-I) include ordinary polymerization methods such as an emulsion polymerization method, an emulsion-suspension polymerization method and a solution polymerization method. However, the emulsion polymerization method is preferred from the viewpoint that the composition ratio of the rubbery polymer and the vinyl monomer mixture (1) to be used can be set in a wide range.

More specifically, for example, there is a method in which the vinyl monomer mixture (1) in the above ratio is graft-polymerized to the polymer in the presence of the rubber-like polymer particles by an emulsion polymerization method. Known polymerization initiators such as persulfates and organic peroxides, and emulsifiers and chain transfer agents that can be used as needed can be used. Further, ordinary conditions such as polymerization temperature and time can be adopted.

The graft copolymer (a-I) in the present invention is obtained by polymerizing the ungrafted copolymer formed during the graft polymerization, that is, the vinyl monomer mixture (1) itself. And the content of the ungrafted copolymer and N, N-
The reduced viscosity at 30 ° C. using dimethylformamide is preferably 6.5 to 48% and 0.1 to 1.0 dl / g, respectively, based on the weight of the graft copolymer (a-I). If the content of the ungrafted copolymer is less than 6.5%, the compatibility with the styrenic resin, the surface gloss, and the rigidity tend to decrease, and if it exceeds 48%, the following graft ratio and rubber are obtained. There is a tendency that the content of the polymer is reduced.

In the above graft polymerization, the graft ratio represented by the formula (1): (graft ratio) = [(weight of graft branch) / (weight of rubbery polymer)] × 100 (1) is 10 to 80. % And 15 to 15
It is preferably 60%, and if it is less than 10%, the compatibility with the styrene resin, moldability, rigidity, and surface gloss tend to decrease, and the molded article surface also tends to be non-uniform,
If it exceeds 80%, the impact resistance tends to decrease.

In the present invention, the graft copolymer (a-
The slurry containing the particles of I) is, as described above, a lubricant (a-
II) and / or particles necessary for efficiently coating the surface of the graft copolymer (a-I) with the copolymer (a-III), for example, particles of the graft copolymer (a-I) Is obtained by adding a coagulant to an aqueous dispersion containing the same by a usual method to aggregate fine particles in the aqueous dispersion, and having a weight average particle diameter of 20 to 500.
It contains agglomerated particles of μm, and the solid content in the slurry is usually about 5 to 40%.

Examples of the coagulant include acids such as sulfuric acid, hydrochloric acid, and acetic acid, and salts such as sodium chloride, magnesium chloride, calcium chloride, magnesium sulfate, and aluminum sulfate. These may be used alone. Also, two or more kinds may be used.

The method for obtaining the slurry is as follows.
For the purpose of reducing fine particles of 53 μm or less in the impact modifier which can be used in the present invention, for example, a gas phase solidification method described in JP-B-61-42923 may be employed.

Lubricants (a-II) used in the present invention
Are used in order to obtain the above-mentioned blocking resistance, for example, stearic acid, fatty acids such as behenic acid, calcium stearate, zinc stearate, fatty acid metal salts such as magnesium stearate, oleic acid amide, erucic acid amide, Ethylenebisstearylamide, fatty acid amides such as compounds having a higher melting point than bisamides synthesized by a dehydration reaction from higher fatty acids such as stearic acid and dicarboxylic acids such as succinic acid and diamines such as ethylenediamine, stearic acid esters,
Stearic acid esters such as pentaerythritol tetrastearate; glycerin fatty acid esters such as oleic acid monoglyceride; fatty acid esters such as hydrogenated castor oil; and higher alcohols such as stearyl alcohol. These may be used alone or in combination of two or more. May be used in combination. Further, it is preferable to use a lubricant having a melting point of 50 ° C. or more from the viewpoint of further improving the anti-blocking property when the temperature becomes high, such as during storage or transportation of the impact resistance improver.

Among these lubricants, ethylene bisstearyl amide and pentaerythritol tetrastearate are preferred from the viewpoint of blocking resistance and molded article properties.

The aqueous dispersion containing the particles of the lubricant (a-II) is obtained by a usual emulsification method such as a phase inversion emulsification method, and as described above, the graft copolymer (a-I) Needed to coat the surface of Further, the slurry containing the particles of the lubricant (a-II) is the same as described above. The method of obtaining this slurry, the weight average particle size of the aggregated particles, the solid content in the slurry,
This is the same as the case of the slurry containing the particles of the graft copolymer (a-I).

The copolymer (a-III) having the above specific composition used in the present invention is used particularly for obtaining anti-blocking properties.
0%, a mixture of 0 to 80% of an aromatic vinyl monomer, 0 to 100% of an acrylate monomer, and 0 to 100% of a methacrylate ester monomer (however, the total amount of these monomers is 100%), and the impact resistance tends to decrease when the amount of the aromatic vinyl monomer exceeds 80%. When the amount of the monomer exceeds 40%, coloring or heat stability tends to be reduced. The copolymer (a-II
Each vinyl monomer in the vinyl monomer mixture (2) used in I) is a vinyl monomer in the vinyl monomer mixture (1) mentioned above for obtaining the graft copolymer (a-I). Monomers can be used.

The composition of the copolymer (a-III) is more preferably represented by the formula (2):

[0032]

(Equation 1)

Wherein α is the proportion (%) of vinyl cyanide in the copolymer (a-III), and β is the copolymer (a-II)
Ratio (%) of (meth) acrylate in I), γ
Is the ratio (%) of the vinyl cyanide subjected to the graft reaction in the graft copolymer (a-I), and δ is the ratio of the (meth) acrylate ester subjected to the graft reaction in the graft copolymer (a-I). (%)]. By making the composition represented by the formula (2), the balance of physical properties such as impact resistance and rigidity of the rubber-reinforced styrene resin is improved.

The reduced viscosity of the methyl ethyl ketone soluble portion of the copolymer (a-III) is 0.2 to 3.0 dl / g.
(N, N-dimethylformamide solution, 30 ° C.), and if it is less than 0.2, the blocking resistance of the impact modifier is lowered, the chemical resistance of the rubber-reinforced styrenic resin, The impact resistance and the like tend to decrease. If it exceeds 3.0, the moldability of the rubber-reinforced styrene resin tends to decrease.

The glass transition temperature of the copolymer (a-III) is preferably 30 ° C. or higher, more preferably 50 ° C. or higher, and if it is lower than 30 ° C., the effect of improving the blocking resistance tends to decrease.

Further, in order to improve the blocking resistance, it is possible to copolymerize a crosslinkable monomer when producing the copolymer (a-III).

Examples of the crosslinkable monomer include divinylbenzene, 1,3-butylene glycol-dimethacrylate, polyethylene glycol dimethacrylate and the like.

The amount of the crosslinking monomer is not particularly limited, but is based on 100 parts of the vinyl monomer mixture (2).
The content is preferably 20 parts or less, and if it exceeds 20 parts, the effect of improving the blocking resistance tends to be saturated, and the impact resistance and moldability of the rubber-reinforced styrene resin tend to be reduced.

Further, when producing the copolymer (a-III) within a range not to impair the effect of improving the blocking resistance, the vinyl monomer mixture ( It is also possible to copolymerize 2). As the amount of the rubbery polymer, the copolymer (a-III) 10
It is preferably 25 parts or less based on 0 parts.

As a method for producing the copolymer (a-III), for example, the same method as that for the graft copolymer (a-I) can be used.

As described above, the aqueous dispersion containing the particles of the copolymer (a-III) can be used as the graft copolymer (a-III).
Necessary for coating the surface of I). Further, a slurry containing particles of the copolymer (a-III) also includes
Same as above. The method for obtaining this slurry, the weight average particle diameter of the aggregated particles, and the solid content in the slurry are the same as those for the slurry containing the graft copolymer (a-I) particles.

The impact modifier according to the present invention comprises 100 parts of the graft copolymer (a-I) particles and 0.01 to 10 parts of the lubricant (a-II) particles and / or the copolymer. It comprises 0.1 to 25 parts of the particles of (a-III).

The particles of the lubricant (a-II) have a particle diameter of 0.01%.
If the amount is less than 1 part, the effect of improving the blocking resistance is small and 1
If it exceeds 0 parts, the rigidity and the like of the rubber-reinforced styrene resin tend to decrease. Further, the copolymer (a-III)
If the particles are less than 0.1 part, the effect of improving the blocking resistance is small, and if it exceeds 25 parts, the impact resistance of the rubber-reinforced styrene resin tends to decrease.

As a method for producing the impact modifier, for example, an aqueous dispersion of the graft copolymer (a-I) is slurried by the above method, and then the lubricant (a-II) and / or the copolymer ( A predetermined amount of each aqueous dispersion of a-III) is mixed and aggregated (however, when the lubricant (a-II) and the copolymer (a-III) are slurries, the aggregation step is excluded).
The obtained particle mixture is subjected to a heat treatment by a usual method, followed by dehydration and drying.

A slurry of the graft copolymer (a-I) and a lubricant (a-II) and / or a copolymer (a-I)
The method of mixing II) with the aqueous dispersion (or slurry) is not particularly limited, and examples thereof include a method using a stirrer or a line mixer.

Examples of the styrene resin usable in the present invention include polystyrene resin, styrene-α-methylstyrene copolymer resin, styrene-maleimide copolymer resin, styrene-acrylonitrile copolymer resin, styrene-maleimide -Acrylonitrile copolymer resin, styrene-α-methylstyrene-acrylonitrile copolymer resin, styrene-α-methylstyrene-acrylonitrile-maleimide copolymer resin, α-methylstyrene-acrylonitrile copolymer resin, styrene-methyl methacrylate Copolymer resins and the like can be mentioned, and these can be used alone or in combination of two or more.

The reduced viscosity of the styrene resin is 0.3
It is preferably in the range of 1.5 dl / g (N, N-dimethylformamide solution, 30 ° C.), and if it is less than 0.3, the impact resistance and chemical resistance of the rubber-reinforced styrene resin are reduced.
Rigidity and the like tend to decrease, and when it exceeds 1.5, moldability tends to decrease.

The method for producing the styrene-based resin is not particularly limited, and may be a known method such as emulsion polymerization, suspension polymerization, solution polymerization, or bulk polymerization. There is no particular limitation on the shape of the styrene resin,
For example, beads, granules, pellets, and powders can be used, but those having a content of fine powder of 53 μm or less of 10% or less are preferable.
If the fine powder exceeds 10%, dust is generated and classification is facilitated.

The properties of the rubber-reinforced styrenic resin of the present invention depend on the composition and the mixing ratio of the impact modifier and the styrenic resin.

The composition of the rubber-reinforced styrenic resin preferably has the formula (3):

[0051]

(Equation 2)

[Wherein λ is a graft copolymer (a-I)
Percentage of vinyl cyanide that has undergone graft reaction in
Is the percentage (%) of the graft-reacted (meth) acrylate in the graft copolymer (a-I), ε is the percentage (%) of vinyl cyanide in the styrene resin, and η is the percentage in the styrene resin. The ratio (%) of the (meth) acrylic acid ester and θ represent the ratio (%) of the maleimide derivative in the styrene-based resin]. Outside the range of the composition represented by the formula (3), the compatibility between the impact modifier and the styrene-based resin becomes poor, and the resulting rubber-reinforced styrene-based resin has reduced impact resistance, rigidity, and the like. There is a tendency for peeling to occur on the surface.

The mixing ratio between the impact modifier and the styrene resin depends on the desired physical properties, but it is preferable to mix the rubber-reinforced styrene resin so that the rubber-like polymer contains 5 to 40%. If it is less than 5%, the impact resistance of the obtained rubber-reinforced styrenic resin is reduced, and if it is more than 40%, there is a tendency that rigidity is reduced or molding workability is reduced.

The method of mixing and melting the impact modifier and the styrene resin is not particularly limited, and may be a conventional method. For example, a predetermined amount of the impact modifier and the styrene resin may be used. Is mixed with a Henschel mixer, Banbury mixer, or the like, and if necessary, melted in a single-screw or multi-screw extruder in the range of 180 ° C. to 300 ° C. and extruded to obtain a pellet-shaped or granulated rubber-reinforced styrene of the present invention. Based resin can be obtained. The screw type of the extruder to be used is not particularly limited. For example, in the case of a single screw extruder, a screw such as a full flight type, a dalmage type, or a dispersion type having a compression ratio of 2 to 5 is used. In the case of a multi-screw extruder, any screw element can be combined. When styrene-based resin is obtained by bulk polymerization, etc., styrene-based resin should be continuously supplied to the extruder from the polymerization vessel, and the impact modifier should be continuously supplied using a side feeder. Is also possible.

When mixing and melting, if necessary, known heat stabilizers, antioxidants, light stabilizers, ultraviolet absorbers, lubricants, plasticizers, pigments, dyes, fillers, flame retardants,
One or more kinds of antistatic agents, antibacterial agents and the like can be added. Further, it is also possible to mix one or more of thermoplastic resins such as polyvinyl chloride, polycarbonate, polyethylene terephthalate, polybutylene terephthalate and polyamide.

The graft copolymer (a-I), lubricant (a-II) and copolymer (a) used in the production method of the present invention.
Preferred combinations of the components of -III) are, for example, the following.

(A-I) graft copolymer 100 parts rubber-like polymer 40 to 85 parts vinyl monomer mixture (1) 15 to 60 parts vinyl cyanide monomer and aromatic 10 to 40 / 90-60 Weight ratio of vinyl monomer (a-II) Lubricant 0.01-10 parts (a-III) Copolymer 0.1-25 parts-Vinyl monomer mixture (2)-Vinyl cyanide monomer Monomer 0-40% ・ Aromatic vinyl monomer 0-80% ・ Acrylic ester monomer 0-100% ・ Methacrylic ester monomer 0-100% (However, these four types of monomers This combination is advantageous for blocking resistance and impact resistance.

More preferably, (a-I) 100 parts of the graft copolymer, 40 to 85 parts of a rubbery polymer composed of a diene polymer or an acrylic polymer, and a vinyl monomer mixture (1) 15 to 60 Parts-Acrylonitrile and 10-40 / 90-60 Weight ratio of styrene (a-II) Fatty acid, fatty acid metal salt, fatty acid amide, glycerin fatty acid ester or lubricant composed of higher alcohol 0.01-10 parts (a-III) 0.1 to 25 parts of polymer ・ Vinyl monomer mixture (2) ・ Acrylonitrile 0 to 40% ・ Styrene 0 to 80% ・ Methyl methacrylate 0 to 100% (However, the total amount of these monomers is 100 %) This combination is excellent in blocking resistance and impact resistance.

[0059]

EXAMPLES Next, the present invention will be described in more detail with reference to manufacturing experimental examples and experimental examples, but the present invention is not limited thereto.

(Production of Graft Copolymer (a-I)) Production Experimental Example 1 Acrylonitrile and styrene were graft-copolymerized in the presence of polybutadiene particles by a usual emulsion polymerization method.
1 part (solid content) of the emulsified phenolic antioxidant was added to 300 parts (100 parts solid content) of the obtained aqueous dispersion,
After stirring, 40 parts of a 5% aqueous sulfuric acid solution was added to coagulate the particles to obtain a slurry having a weight average particle diameter of 120 μm.

The obtained graft copolymer (a-I
Regarding -1), the graft ratio and the like were examined by an ordinary method. Table 1 shows the results.

Manufacturing Experimental Examples 2 to 5 Manufacturing Experimental Example 1 except that the compositions shown in Table 1 were adopted.
The graft copolymers (a-I-2) to (a-
I-5) was obtained, and the graft ratio and the like were examined in the same manner as in Production Experimental Example 1. Table 1 shows the results.

[0063]

[Table 1]

The type of the rubbery polymer shown in Table 1
The types of vinyl monomers are as follows.

PBD: polybutadiene PBA: polybutyl acrylate AN: acrylonitrile St: styrene MMA: methyl methacrylate (production of lubricant (a-II)) Production experiment example 6 10% ethylenebisstearylamide (lubricant) by a usual method An aqueous dispersion of (a-II-1) was obtained.

Production Experimental Example 7 An aqueous dispersion of pentaerythritol tetrastearate (lubricant (a-II-2)) was obtained by an ordinary method.

(Production of Copolymer (a-III)) Production Experimental Example 8 A copolymer composed of 27% acrylonitrile and 73% styrene obtained by an emulsion polymerization method and having a reduced viscosity of methyl ethyl ketone-soluble component of 0.60. (Dl / g), an aqueous dispersion of the copolymer (a-III-1) having a solid content of 31% was obtained.

Production Experimental Example 9 A copolymer composed of 55% of methyl methacrylate, 29% of styrene, 11% of acrylonitrile, and 5% of 1,3-butylene glycol dimethacrylate obtained by an emulsion polymerization method, and having a methyl ethyl ketone insoluble content of 70%. Thus, an aqueous dispersion of the copolymer (a-III-2) having a reduced viscosity of 2.9 and a solid content of 29% of a methyl ethyl ketone-soluble component was obtained.

(Production of impact resistance improving agent) Production Experimental Example 10 Graft copolymer (a-I-) obtained in Production Experimental Example 1
The lubricant (a-II) obtained in Production Experimental Example 6 was added to 100 parts (as a solid content) of the slurry produced from the aqueous dispersion of 1).
After adding 1 part (as a solid content) of the aqueous dispersion of -1) and aggregating the particles, heat treatment, dehydration and drying were performed to obtain a powder (impact modifier (A-1)).

The obtained powder was measured for bulk specific gravity, blocking resistance, and average particle size by the following methods by the following methods.

Bulk specific gravity: The obtained impact modifier was measured by a usual method.

Blocking resistance: 30 g of the obtained impact resistance improver was weighed and placed in a cylindrical container having a diameter of 40 mm.
A block was formed by applying a load of 5 kg / cm ² at 60 ° C. for 3 hours, and the block was subjected to vibration of 100 Hz with a powder tester PFE manufactured by Hosokawa Micron Corp. for 100 seconds to disintegrate the powder and passed through an 18 mesh sieve. Of the total powder was determined. The higher the value, the higher the blocking resistance. Table 2 shows the results.

Production Experimental Examples 11 to 20 Graft copolymer (a-I) and lubricant (a-I) shown in Table 2
I) and the copolymer (a-III) except that powder (impact modifier (A
-2) to (A-11)), and the bulk specific gravity, the blocking resistance, and the average particle diameter were measured in the same manner as in Production Example 10. Table 2 shows the results.

[0074]

[Table 2]

(Production of Styrene Resin) Production Experimental Example 21 Consisting of 30% acrylonitrile and 70% styrene produced by a suspension polymerization method, and having a reduced viscosity of 0.67 (dl / g).
And a bead-like resin having an average particle diameter of 500 μm and a fine powder amount of not more than 53 μm and 0.1% or less was obtained.

Production Experimental Example 22 A styrene resin (B-B) comprising 55% of styrene, 23% of acrylonitrile and 20% of phenylmaleimide and having a reduced viscosity of 0.58 dl / g, produced by a bulk polymerization method.
2), an average length of 3.1 mm, an average diameter of 25 mm,
A pellet-shaped resin having an amount of fine powder of not more than 53 μm and not more than 0.1% was obtained.

(Production of Rubber-Reinforced Styrene-Based Resin) Experimental Examples 1 to 14 0.5 parts of ethylenebisstearylamide was added in the proportions shown in Table 3 with respect to 100 parts of the total of the impact modifier and the styrene-based resin. 0.1 part of ADK STAB AO-20 (phenolic antioxidant) is mixed to obtain a compound,
200 to 2 with a vent type single screw extruder with a screen diameter of 40 mm
The mixture was melt-kneaded at 60 ° C. to obtain pellets (rubber-reinforced styrene resins (C-1) to (C-2)).

The properties of the compound and the obtained rubber-reinforced styrene resin were tested by the following methods. All the impact modifiers were 5k at 60 ° C.
A g / cm ² load applied for 7 days was used.

Compound uniformity: The compound mixed with a Henschel mixer was observed and evaluated according to the following criteria.

：: The impact resistance improver and the styrene resin were uniformly dispersed, and no block-like thing was observed.

X: Block-like ones in which the impact modifier and the styrene resin are unevenly present are observed.

Extrusion stability: At the time of melt extrusion, the pointer of the ammeter of the extruder and the strand were observed and evaluated according to the following criteria.

：: The strand is stable, and the pointer of the ammeter hardly touches.

X: The strand is unstable or the strand breaks, and the pointer of the ammeter also touches.

Izod impact value (kg · cm / cm):
ASTM D-256 (1/4 inch thick, with notch, 2
3 ° C.).

Tensile strength (kg / cm ² ): ASTM D-
638 (23 ° C.).

Heat resistant deformation temperature (° C.): ASTM D-64
8 (1/4 inch thickness, 18.6 kg / cm ² load).

Gloss (%): 150 mm × 100 mm × 3
The 60 ° reflectivity at the center of a flat plate (mirror surface) of mm was measured.

MI (melt index) (g / 10
Min): ASTM D-1238 (230 ° C x 10 kg)
It measured according to.

Surface property of molded article: The flat plate used for measuring gloss was evaluated according to the following criteria.

：: Surface gloss is uniform, and no defect such as a flow mark at the gate is observed.

X: Defects such as uneven surface gloss and / or flow marks at the gate are observed.

Table 3 shows the results.

[0094]

[Table 3]

[0095]

According to the production method of the present invention, by using an impact resistance improver excellent in powder properties such as blocking resistance, extrusion stability is good and high quality, that is, impact resistance is improved. A rubber-reinforced styrene-based resin having excellent molded article properties can be empirically and easily produced.

──────────────────────────────────────────────────続 き Continuation of the front page (56) References JP-A 1-311129 (JP, A) JP-A 55-90520 (JP, A) JP-A 5-262953 (JP, A) JP-A 64- 26644 (JP, A) JP-A-4-3355052 (JP, A) (58) Fields investigated (Int. Cl. ⁷ , DB name) C08L 51/04 C08L 25/04

Claims (4)

(57) [Claims] 1. A vinyl monomer mixture comprising a vinyl cyanide monomer and an aromatic vinyl monomer in a weight ratio of 10 to 40/90 to 60 to 40 to 85 parts by weight of a rubbery polymer (1).
Graft copolymer (a-I) particles 100 obtained by graft polymerization of 15 to 60 parts by weight (the total amount of rubbery polymer and vinyl monomer mixture (1) is 100 parts by weight) An aqueous dispersion containing 0.01 to 10 parts by weight of particles of lubricant (a-II) and / or 0 to 40% by weight of vinyl cyanide monomer and 80% by weight and 0 acrylate monomer
-100% by weight and methacrylic acid ester monomer 0-10
A copolymer (a-II) obtained by copolymerizing a vinyl monomer mixture (2) containing a mixture consisting of 0% by weight (the total amount of these four monomers is 100% by weight)
A rubber-reinforced styrene obtained by mixing an aqueous dispersion containing 0.1 to 25 parts by weight of the particles of I), heat-treating a particle mixture obtained by agglomeration, and mixing an impact modifier obtained by drying and a styrene resin. Production method for resin. 2. As the particle mixture, a slurry containing particles of the lubricant (a-II) and / or a slurry containing particles of the lubricant (a-II) are added to the slurry containing the particles of the graft copolymer (a-I). 2. The method for producing a rubber-reinforced styrene-based resin according to claim 1, wherein a particle mixture obtained by mixing a slurry containing particles is used. 3. The method for producing a rubber-reinforced styrene resin according to claim 1, wherein the rubbery polymer is used in an amount of 5 to 40% by weight based on the weight of the rubber-reinforced styrene resin. 4. A styrene resin having a reduced viscosity of 0.3 to 1.5 dl / g at 30 ° C. using N, N-dimethylformamide as the styrene resin. A method for producing the rubber-reinforced styrenic resin described in the above.