JPWO2019188929A1 - Rubber-containing graft polymer and resin composition - Google Patents

Abstract

A butadiene rubber-containing graft polymer satisfying the following conditions (1), (2) and (3) is provided. (1) The ratio of the number of particles having a circle-equivalent diameter of 400 nm or more to the number of particles having a circle-equivalent diameter of 100 nm or more is 5% or less. (2) The volume average particle diameter calculated by excluding particles having a circle-equivalent diameter of 100 nm or less is 150 to 250 nm. (3) The ratio of the number of particles having a circle-equivalent diameter of 150 nm or more and a circularity of 0.75 or less to the number of particles having a circle-equivalent diameter of 150 nm or more is 70% or more.

Description

The present invention relates to rubber-containing graft polymers and resin compositions.
The present application claims priority based on Japanese Patent Application No. 2018-061724 filed in Japan on March 28, 2018, the contents of which are incorporated herein by reference.

The rubber-containing graft polymer is a rubber-like polymer graft-polymerized with a vinyl monomer. The rubber-containing graft polymer is produced by emulsion polymerization and can be dispersed in a wide variety of resins while maintaining a predetermined rubber particle size and rubber structure. Therefore, the impact resistance of the molded product can be improved by blending the rubber-containing graft polymer with the resin.

To improve impact resistance, a rubber-containing graft polymer having a particle size of 150 to 250 nm is usually used. As the rubber-containing graft polymer having such a particle size, a coagulated and hypertrophied rubber-containing graft polymer is also used. The aggregated and enlarged rubber-containing graft polymer is obtained by graft-polymerizing a vinyl monomer to the aggregated and enlarged rubber-like polymer obtained by aggregating and enlarging a rubber-like polymer having a small particle size. As an agglutination and enlargement technique for rubber-like polymers, an agglutination and enlargement technique using an electrolyte, a high molecular weight organic acid latex or an acid is known.

Many studies on agglomeration and hypertrophy technology using acid have been conducted for a long time. A method of adding an acid to the rubbery polymer latex to lower the pH of the latex, coagulating and enlarging the latex particles, and then adding a basic substance to make the pH of the system alkaline and stabilizing the latex. well known. However, the problem is how to control the particle size distribution of rubber after coagulation and hypertrophy.

Patent Document 1 describes a core-shell graft polymer to be blended with polycarbonate, polyester-based resin, or a mixture thereof to improve impact resistance.
Patent Document 2 describes a graft polymer to be blended with a polycarbonate resin composition to improve impact resistance and processability.
Patent Document 3 describes a graft polymer to be blended with a vibration-damping thermoplastic resin composition to improve impact resistance.
Patent Document 4 describes a graft polymer to be blended with a thermoplastic resin composition to improve impact resistance.

Japanese Patent Publication No. 2008-520805 Japanese Unexamined Patent Publication No. 2001-342336 Japanese Unexamined Patent Publication No. 11-14286 Japanese Unexamined Patent Publication No. 2014-122255

However, according to the studies by the present inventors, the molded product of the resin composition containing the graft polymers described in Patent Documents 1 to 4 does not have sufficient impact resistance.

Therefore, an object of the present invention is to provide a butadiene rubber-containing graft polymer and a resin composition which can obtain a molded product having excellent impact resistance and have excellent productivity.

The above problem is solved by the following configuration.
[1] A butadiene rubber-containing graft polymer that satisfies the following conditions (1), (2), and (3).
(1) The ratio of the number of particles having a circle-equivalent diameter of 400 nm or more to the number of particles having a circle-equivalent diameter of 100 nm or more is 5% or less.
(2) The volume average particle diameter calculated by excluding particles having a circle-equivalent diameter of 100 nm or less is 150 to 250 nm.
(3) The ratio of the number of particles having a circle-equivalent diameter of 150 nm or more and a circularity of 0.75 or less to the number of particles having a circle-equivalent diameter of 150 nm or more is 70% or more.
[2] The butadiene rubber-containing graft polymer according to [1], which contains 200 mass ppm or more of a phosphorus element.
[3] The butadiene rubber-containing graft polymer according to [1] or [2], which contains 100 mass ppm or less of sodium element.
[4] The butadiene rubber-containing graft polymer according to any one of [1] to [3], which contains at least 1% by mass in total of one or more selected from the group consisting of fatty acids and salts thereof.
[5] Any of [1] to [4], wherein 95% by mass or more of the total mass of the units derived from the vinyl monomer of the graft chain of the butadiene rubber-containing graft polymer is the unit derived from methyl methacrylate. The butadiene rubber-containing graft polymer according to item 1.
[6] When the butadiene rubber-containing graft polymer is mixed with an organic solvent and separated into an organic solvent-insoluble component and an organic solvent-soluble component, the organic solvent-insoluble component forms a graft chain of the butadiene rubber-containing graft polymer. The butadiene rubber-containing graft polymer according to any one of [1] to [5], wherein the graft chain contains a caprolactone unit.
[7] A rubber latex containing butadiene rubber and a vinyl monomer are mixed at a mass ratio of the butadiene rubber / the vinyl monomer = 45/55 to 90/10, and the vinyl monomer is mixed with the butadiene rubber. The butadiene rubber-containing graft polymer according to any one of [1] to [6], which is obtained by graft-polymerizing the above.
[8] The butadiene rubber-containing graft polymer according to [7], which is obtained by graft-polymerizing the vinyl monomer on the butadiene rubber and then coagulating with calcium acetate.
[9] To 100 parts by mass of the solid content of the rubber latex containing butadiene rubber, 0.1 to 10 parts by mass of an aqueous phosphoric acid solution was added in terms of solid content to coagulate and enlarge the butadiene rubber.
The obtained aggregated and enlarged rubber-like polymer latex containing the aggregated and enlarged butadiene rubber and the vinyl monomer are combined with the solid content of the aggregated and enlarged rubbery polymer latex / the vinyl monomer = 45 / 55-90. Mix at a mass ratio of 1/10 and
Obtained by graft-polymerizing the vinyl monomer on the coagulated and hypertrophied butadiene rubber.
A butadiene rubber-containing graft polymer containing 2.5% by mass or less of particles having a volume average particle diameter of 150 to 220 nm and a circle-equivalent diameter of 400 nm or more.
[10] The butadiene rubber-containing graft polymer according to [9], which contains 8% by mass or less of particles having a circle-equivalent diameter of 100 nm or less.
[11] The butadiene rubber-containing graft according to [9] or [10], which is mixed at a mass ratio of solid content of the coagulated and hypertrophied rubber-like polymer latex / vinyl monomer = 45/55 to 85/15. Polymer.
[12] The butadiene rubber-containing graft polymer according to any one of [9] to [11], wherein the vinyl monomer contains 95% by mass or more of methyl methacrylate.
[13] The butadiene rubber-containing graft polymer according to any one of [9] to [12], wherein the vinyl monomer contains caprolactone.
[14] The butadiene rubber-containing graft polymer according to any one of [9] to [13], which contains 1 part by mass or more of a fatty acid-based emulsifier with respect to 100 parts by mass of the butadiene rubber-containing graft polymer.
[15] A resin composition containing the butadiene rubber-containing graft polymer according to any one of [1] to [14] and a thermoplastic resin.
[16] The resin composition according to [15], wherein the thermoplastic resin contains an aromatic polycarbonate resin.
[17] The resin composition according to [15] or [16], wherein the thermoplastic resin contains a polyester resin.

According to the present invention, it is possible to provide a molded product having excellent impact resistance and to provide a butadiene rubber-containing graft polymer and a resin composition having excellent productivity.

Hereinafter, embodiments for carrying out the present invention will be described in detail. The present invention is not limited to the embodiments described below, and various modifications can be made without changing the gist of the present invention.

[Butadiene rubber-containing graft polymer]
The butadiene rubber-containing graft polymer of the present invention satisfies the following conditions (1), (2) and (3).
(1) The ratio of the number of particles having a circle-equivalent diameter of 400 nm or more to the number of particles having a circle-equivalent diameter of 100 nm or more is 5% or less.
(2) The volume average particle diameter calculated by excluding particles having a circle-equivalent diameter of 100 nm or less is 150 to 250 nm.
(3) The ratio of the number of particles having a circle-equivalent diameter of 150 nm or more and a circularity of 0.75 or less to the number of particles having a circle-equivalent diameter of 150 nm or more is 70% or more.

The circle-equivalent diameter, volume average particle diameter, circularity, and number ratio are obtained by the following methods.

A powder obtained by drying the latex of a butadiene rubber-containing graft polymer is added to a polycarbonate resin in an amount of 3% by mass and melt-kneaded to form a strand having a diameter of 3 mm. Strands are stained with osmium tetroxide (OsO ₄ ) and microtomes are used to make ultrathin sections. An ultrathin section is observed and imaged using a transmission electron microscope (H-7600, manufactured by Hitachi High-Technologies Corporation) to obtain an image.

The obtained image is image-processed using an image analysis processing device (Image Pro Plus, manufactured by Nippon Roper Co., Ltd.). Image processing is performed in accordance with JIS Z 8827-1: 2008.

The ratio (%) of the number of particles with a circle-equivalent diameter of 400 nm or more to the number of particles with a circle-equivalent diameter of 100 nm or more is the number of particles with a circle-equivalent diameter of 100 nm or more and the number of particles with a circle-equivalent diameter of 400 nm or more. Measure and calculate.
For the volume average particle diameter (Dv), the volume average particle diameter is calculated for the remaining particles excluding the particles having a circle-equivalent diameter of 100 nm or less. Here, Dv is a 50% volume diameter.

The ratio (%) of the number of particles having a circle-equivalent diameter of 150 nm or more and a circularity of 0.75 or less to the number of particles having a circle-equivalent diameter of 150 nm or more is converted into a circle using the above-mentioned TEM and Image Pro Plus. It is calculated by measuring the number of particles having a diameter of 150 nm or more and the number of particles having a circularity of 0.75 or less among particles having a circle-equivalent diameter of 150 nm or more.

Circularity is a numerical value representing the complexity of an image and is defined by the following equation (1).
In the case of the rubber-containing graft polymer that has not been subjected to the coagulation and hypertrophy treatment, the circularity is 0.8 to 1 because there is strain from a perfect circle.
In the case of the rubber-containing graft polymer that has been subjected to the agglutination-enlargement treatment, the circularity is smaller than that of the unenlarged one due to the aggregation of the particles, and the circularity is less than 0.8.

When measuring the circularity with a transmission electron microscope, it is preferable to measure from a sufficiently large particle because cutting the end of the enlarged particle when cutting the sample piece may result in an unenlarged particle cross section.
Circularity = 4 x π x circle area / (peripheral length ² ) ... (1)

Since the butadiene rubber-containing graft polymer of the present invention satisfies the above conditions (1), (2) and (3), a molded product having excellent impact resistance can be obtained and the productivity is excellent.

When the butadiene rubber-containing graft polymer of the present invention is used as an impact resistance modifier for a thermoplastic resin, the volume average particle size is 150 to 250 nm, and particles of 400 nm or more are contained in an amount of 2.5% by mass or less and 100 nm. It is preferable that particles having the following particle size are contained in an amount of 8% by mass or less. Within this range, the phase-separated structure of the molded product does not collapse, and the impact resistance is more excellent.

The ratio of the number of particles having a circle-equivalent diameter of 150 nm or more and a circularity of 0.75 or less to the number of particles having a circle-equivalent diameter of 150 nm or more is preferably 70% or more, more preferably 70 to 100%, and more preferably 80 to 80 to 100%. 100% is even more preferred, and 90-100% is even more preferred. The larger this ratio is, the more the productivity is improved because there are no unenlarged particles and the particles are sufficiently enlarged. In addition, the impact resistance is improved because the particles can be fused to each other to maintain the aggregated state.

Further, the butadiene rubber-containing graft polymer of the present invention preferably contains 200 mass ppm or more of phosphorus element.
The phosphorus element content (phosphorus content) of the butadiene rubber-containing graft polymer is determined by wet decomposition of the butadiene rubber-containing graft polymer to prepare a test solution, and the prepared test solution is quantified for phosphorus by an ICP emission spectrometer. Ask.
The phosphorus content of the butadiene rubber-containing graft polymer of the present invention is preferably 200 mass ppm or more, more preferably 500 mass ppm or more, still more preferably 1000 mass ppm or more. The upper limit of the phosphorus content is not particularly limited, but is usually 5000 mass ppm or less. When the phosphorus content is in this range, the volume average particle diameter of the butadiene rubber-containing graft polymer is within an appropriate range, and the impact resistance of the obtained molded product is more excellent.

Further, the butadiene rubber-containing graft polymer of the present invention preferably contains 100 mass ppm or less of sodium element.
For the sodium element content (sodium content) of the butadiene rubber-containing graft polymer, a test solution is prepared by wet-decomposing the butadiene rubber-containing graft polymer, and the prepared test solution is quantified with an ICP emission spectrometer. Ask.
The sodium content of the butadiene rubber-containing graft polymer of the present invention is preferably 100 mass ppm or less, more preferably 50 mass ppm or less, and even more preferably 30 mass ppm or less. The lower limit of the sodium content is not particularly limited, but is usually 0 mass ppm. When the sodium content is in this range, the molding processability of the obtained resin composition is more excellent.

Further, the butadiene rubber-containing graft polymer of the present invention preferably contains at least 1% by mass in total of one or more selected from the group consisting of fatty acids and salts thereof.
The fatty acid is not particularly limited, but at least one selected from the group consisting of palmitic acid, oleic acid, stearic acid, dipotassium alkenylsuccinate and rosinic acid is preferable. The salt of the above fatty acid is not particularly limited, but salts of these fatty acids are preferable. Examples of the salt include, but are not limited to, alkali metal salts such as sodium salt and potassium salt, and alkaline earth metal salts such as calcium.
The content (fatty acid content) of one or more selected from the group consisting of fatty acids and salts thereof of the butadiene rubber-containing graft polymer is palmitic acid using a gas chromatograph after the rubber-containing graft polymer is methyl-esterified. Obtained by measuring the masses of acid, oleic acid, stearic acid, dipotassium alkenyl succinate and logonic acid.
The fatty acid content of the butadiene rubber-containing graft polymer of the present invention is preferably 1% by mass or more, more preferably 1.2% by mass or more, still more preferably 1.5% by mass or more. The upper limit of the fatty acid content is not particularly limited, but is usually 5.0% by mass.

Further, it is preferable that 95% by mass or more of the total mass of the units derived from the vinyl monomer of the graft chain of the butadiene rubber-containing graft polymer of the present invention is the unit derived from methyl methacrylate (MMA).
The ratio of the total mass of the units derived from MMA to the total mass of the units derived from the vinyl monomer of the graft chain of the butadiene rubber-containing graft polymer of the present invention (MMA content, unit: mass%) is as follows. Measured by.

(Preparation of dry sample)
(1) A solution consisting of 1% by mass of a butadiene rubber-containing graft polymer and 99% by mass of tetrahydrofuran is prepared.
(2) The solution prepared in (1) is stirred for 1 hour.
(3) The solution stirred in (2) is centrifuged at 14,000 rpm for 60 minutes.
(4) Extract the supernatant and put it in a flask.
(5) Add the same amount of organic solvent as (1) to the precipitate (insoluble in tetrahydrofuran) again.
(6) The operations of (3) to (5) are repeated three times.
(7) The flask is set in a constant temperature bath having a temperature of 70 ° C., and the volatile matter is distilled off by an evaporator.
(8) The residue in the flask is dried at 80 ° C. for 8 hours in a steam dryer, and further dried at 65 ° C. for 6 hours in a vacuum dryer to obtain a dried sample of a tetrahydrofuran-soluble component.
(9) A container containing the precipitate was set in a constant temperature bath at 60 ° C. to volatilize the organic solvent, and then dried in a vacuum dryer at 65 ° C. for 6 hours to obtain tetrahydrofuran of the butadiene rubber-containing graft polymer. Obtain a dry sample of insoluble matter.

(Quantification of methyl methacrylate units (MMA) in the graft chain)
The obtained dried sample of tetrahydrofuran insoluble matter was subjected to qualitative and quantitative analysis of the monomer unit of the graft chain under the following conditions using a thermal decomposition GC-MS (gas chromatography-mass spectrometer), and the content ratio of the methyl methacrylate unit ( Weight%) is calculated.
1) Strong polarity column: DP-FFAR (manufactured by Agilent Technologies) 30m x 0.25mm x 0.25μm
2) Column flow rate: 1.0 mL / min
3) Injection port, interface temperature: 230 ° C
4) Pyrolysis temperature: 500 ° C

Further, when the butadiene rubber-containing graft polymer of the present invention is mixed with an organic solvent and separated into an organic solvent-insoluble component and an organic solvent-soluble component, the organic solvent-insoluble component is the butadiene rubber-containing graft polymer of the present invention. It preferably contains a graft chain, the graft chain containing a caprolactone unit.
The caprolactone unit of the graft chain is measured by the following method.

(Preparation of dry sample)
A dry sample of tetrahydrofuran insoluble is obtained in the same manner as in the case of quantification of MMA.

(Quantification of caprolactone unit (CL) in graft chain)
-Preparation of dried graft chain sample (1) Prepare 6% by mass of tetrahydrofuran (THF) insoluble in the butadiene rubber-containing graft polymer and 94% by mass of a 1: 1 mixed solution of chloroform and methylene chloride to prepare a dispersion solution.
(2) Put the dispersion solution in an ozone absorption bottle and immerse it in a dry ice-methanol solution prepared at -60 ° C or lower.
(3) Ozone gas generated from the ozone generator is blown into the absorption bottle to add ozone.
(4) After adding ozone (the absorption liquid turns blue), air is blown in to remove excess ozone.
(5) Adjust the beaker to a solution of 10% by mass of a reducing agent (sodium hydride) and 90% by mass of methanol, and stir with a magnetic stirrer. After dissolution, the absorbing solution of (4) is added and stirred for 3 hours or more.
(6) After stirring, a hydrochloric acid aqueous solution (1: 1 = hydrochloric acid: water) having a mass corresponding to 1/5 of the mass of the solution of (5) is added to the solution of (5), and the mixture is stirred for 3 hours or more.
(7) After stirring, the mixture is transferred to a separating funnel and separated into two layers. This lower layer is drained into an eggplant flask.
(8) The eggplant flask is set in a constant temperature bath at 65 ° C., and the volatile matter is distilled off by an evaporator.
(9) The residue in the eggplant flask is vacuum dried at 65 ° C. for 8 hours or more to obtain a graft chain dried sample.

-Quantitative determination of caprolactone units (CL) Caprolactone was obtained by qualitatively and quantitatively analyzing the obtained graft chain dried sample using a thermal decomposition GC-MS (gas chromatography-mass spectrometer) under the following conditions. Calculate the content ratio (% by mass) of the unit.
1) Strong polarity column: DP-FFAR (manufactured by Agilent Technologies) 30m x 0.25mm x 0.25μm
2) Column flow rate: 1.0 mL / min
3) Injection port, interface temperature: 230 ° C
4) Pyrolysis temperature: 500 ° C

The butadiene rubber-containing graft polymer of the present invention can be produced by graft-polymerizing a vinyl monomer on a butadiene rubber that has been subjected to a coagulation and hypertrophy treatment. Depending on the particle size of the butadiene rubber, the coagulation and enlargement treatment may be omitted.

The butadiene rubber is not particularly limited as long as it contains a butadiene unit, and examples thereof include polybutadiene, acrylonitrile-butadiene rubber, and styrene-butadiene rubber. The content of the unit derived from 1,3-butadiene in the butadiene rubber is not particularly limited, but is preferably 50% by mass or more, more preferably 75% by mass or more, from the viewpoint of impact strength when blended in a thermoplastic resin. It is preferable, and 90% by mass or more is more preferable.
Examples of the monomer copolymerizable with 1,3-butadiene are monofunctional monomers such as styrene, ethylene, acrylonitrile, and alkyl (meth) acrylate; divinylbenzene, ethylene glycol dimethacrylate, butylene glycol diacrylate. , Triallyl cyanurate, triallyl isocyanurate, trimethylolpropane triacrylate, pentaerythritol tetraacrylate and other polyfunctional monomers. These monomers can be used alone or in combination of two or more.

The volume average particle diameter of the butadiene rubber is not particularly limited, but is preferably 150 nm or less, and more preferably 100 nm or less. Even if the volume average particle size of the butadiene rubber exceeds 150 nm, it does not interfere with the coagulation and enlargement treatment. If butadiene rubber having a volume average particle size of more than 150 nm is to be obtained by emulsion polymerization, polymerization for a long time is required, which reduces the productivity of emulsion polymerization. Then, the effect of improving the productivity of the coagulation and hypertrophy treatment is reduced.

In the present invention, a rubber latex containing butadiene rubber is emulsion-polymerized using an alkali metal salt of a fatty acid as an emulsifier, and an emulsifier having an acidic property and good surface activity is added in the coagulation enlargement step. After that, it is preferable to add an aqueous phosphate solution as a flocculant and then neutralize with a basic substance to coagulate and enlarge the rubber latex containing butadiene rubber.

The fatty acid is a hydrocarbon compound containing a carboxylic acid. When polymerization is carried out using an alkali metal salt of a fatty acid as an emulsifier, when sulfuric acid or the like is added as a strong acid coagulant to the latex of the obtained graft polymer, the alkali metal salt of the fatty acid as an emulsifier becomes a fatty acid having low water solubility. It changes to. As a result, the graft polymer and water are separated, so that the graft polymer can be easily recovered. In this case, the produced graft polymer contains fatty acids. The graft polymer of the present invention preferably contains a fatty acid. The content of fatty acid in the graft polymer of the present invention is not particularly limited, but is preferably 1% by mass or more, more preferably 1.2% by mass or more, and further preferably 1.5% by mass or more. When measuring fatty acids, it is particularly preferable that one or more selected from the group consisting of palmitic acid, stearic acid, oleic acid, alkenyl succinic acid and rosin acid is detected.

The alkali metal salt of the fatty acid used as an emulsifier is not particularly limited, and examples thereof include mixed fatty acid sodium, mixed fatty acid potassium, sodium oleate, potassium oleate, sodium stearate, potassium stearate, and disproportionate potassium loginate. Can be mentioned. Alkali metal salts of these fatty acids can be used alone or in combination of two or more.

The amount of the alkali metal salt added to the fatty acid may be an amount required to maintain the stability of the latex during emulsion polymerization, and is not particularly limited, but is usually based on 100 parts by mass of the total butadiene rubber monomer. , 0.5 to 5 parts by mass is preferable.

The emulsifier that is acidic and has good surface activity, which is used for coagulation and enlargement, is not particularly limited, but an emulsifier having a sulfonic acid group and a salt of an alkali metal is preferable. Examples of such emulsifiers include sodium alkylbenzene sulfonate, polyoxyethylene alkyl ether sulfate, sodium alkyldiphenyl ether disulfonate, sodium alkylnaphthalene sulfonate and sodium dialkyl sulfosuccinate. These emulsifiers can be used alone or in combination of two or more.

The amount of the emulsifier added, which is acidic and has good surface activity, is preferably 0.01 to 0.5 parts by mass, more preferably 0.1 to 0.3 parts by mass, based on 100 parts by mass of the solid content of the rubber latex. preferable.

When the amount of the emulsifier added is within this range, the possibility that a large amount of rubber lumps are generated due to the addition of the coagulant is low, and the effect of enlarging the rubber particles is also good.

The timing 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.

A phosphoric acid aqueous solution is preferable as the flocculant used for coagulation and hypertrophy. The amount of the flocculant added is not particularly limited, but is preferably 0.1 to 10 parts by mass in terms of solid phosphate content with respect to 100 parts by mass of the butadiene rubber. Kyosan such as sulfuric acid or a weak acid such as acetic acid can also be used. An aqueous phosphoric acid solution is particularly preferable from the viewpoint of stability of the coagulated and enlarged rubber latex.

It is desirable that the concentration of the phosphoric acid aqueous solution is as high as possible from the viewpoint of productivity within a range that does not generate rubber lumps at the time of addition. Specifically, the concentration of the phosphoric acid aqueous solution is preferably 0.3 to 40% by mass, more preferably 0.5 to 20% by mass.

The basic substance used for neutralization after the addition of the acid is not particularly limited, but sodium hydroxide, potassium hydroxide, sodium carbonate or potassium carbonate is preferable, and an aqueous solution of potassium hydroxide is more preferable. Even if the concentration of the aqueous solution of the basic substance is high, the problem of forming rubber lumps does not occur. The concentration of the aqueous solution of the basic substance is not particularly limited, but is preferably 5 to 60% by mass.

The temperature of the system during coagulation and hypertrophy is not particularly limited, but is preferably 10 to 60 ° C. The progress of coagulation and enlargement of butadiene rubber is not slowed down, and the particle size can be easily controlled.

The average volumetric particle size of the coagulated and enlarged butadiene rubber can be arbitrarily controlled by changing the amount of acid, the amount of an emulsifier added which is acidic and has good surface activity, and the like. When the butadiene rubber-containing graft polymer of the present invention is used as an impact resistance modifier for a thermoplastic resin, 2.5% by mass of particles having a volume average particle diameter of 150 to 250 nm and a circle-equivalent diameter of 400 nm or more. It is preferably contained below. Further, it is more preferable that particles having a circle-equivalent diameter of 100 nm or less are contained in an amount of 8% by mass or less. When the content of particles having a circle-equivalent diameter of 400 nm or more is within this range, the phase-separated structure of the molded product is not broken, and the impact resistance of the obtained molded product is better. Further, when the content of particles having a circle-equivalent diameter of 100 nm or less is within this range, the impact resistance of the obtained molded product is better.

As described above, the average volume particle size and particle size distribution of the butadiene rubber-containing graft polymer of the present invention are determined by image processing in accordance with JIS Z 8827-1: 2008.

The roundness of the rubber-containing graft polymer is determined by image processing as described above.

The vinyl monomer used in the graft polymerization is not particularly limited, but it is preferable that the vinyl monomer contains methyl methacrylate as a main component. Examples of vinyl monomers other than methyl methacrylate include aromatic vinyl compounds such as styrene and α-methylstyrene; acrylate esters such as methyl acrylate and butyl acrylate; and methacrylic acid esters such as ethyl methacrylate. .. The content of the vinyl monomer other than methyl methacrylate is preferably 5% by mass or less with respect to the total mass of the vinyl monomer to be graft-polymerized. As the vinyl monomer other than methyl methacrylate, an acrylic acid ester having a fatty acid ester at the terminal, which is represented by the following formula (2), is preferable.
CH ₂ = CR ¹ COO (CH ₂ ) ₂ O [CO (CH ₂ ) _m O] _n H (2)
In formula (2): R ¹ represents a hydrogen atom or a methyl group. m is an integer of 3 to 10. n is an integer of 1-10.

As the acrylic acid ester having a fatty acid ester at the terminal, caprolactone is preferable from the viewpoint of reactivity with a thermoplastic resin, and caprolactone-modified (meth) acrylic acid ester having a ring-opening lactone moiety is particularly preferable. The caprolactone-modified (meth) acrylic acid ester is obtained by an addition reaction between a hydroxyl group-containing polymerizable unsaturated monomer and ε-caprolactone, and the one represented by the following formula (3) is preferably used.
CH ₂ = CR ² COO (CH ₂ ) ₂ O [CO (CH ₂ ) ₅ O] _n H (3)
In formula (3): R ² represents a hydrogen atom or a methyl group. n is an integer of 1-5.

The content of the butadiene rubber in the butadiene rubber-containing graft polymer of the present invention is not particularly limited, but is preferably 45 to 90% by mass, more preferably 50 to 90% by mass, and 75 by mass, from the viewpoint of impact strength of the molded product. ~ 90% by mass is more preferable, 77 to 90% by mass is more preferable, and 80 to 90% by mass is particularly preferable.

The glass transition temperature of the polymer composed of the vinyl monomer constituting the graft chain is not particularly limited, but is preferably 80 ° C. or higher, more preferably 90 to 105 ° C. For example, a copolymer of methyl methacrylate and butyl acrylate is preferably used because the glass transition temperature tends to be in the range of 90 to 105 ° C.

Examples of the emulsifier used in the graft polymerization include alkali metal salts of acids such as fatty acids, sulfonic acids, sulfuric acids and phosphoric acids.

The latex-state butadiene rubber-containing graft polymer obtained by graft polymerization can be obtained as a powder by coagulation, washing and then drying, or by spray recovery. When recovered by coagulation, the coagulant includes various inorganic or organic acids and salts thereof, for example, sulfuric acid, nitrate, hydrochloric acid, phosphoric acid, phosphite, acetic acid, aluminum chloride, magnesium sulfate, sodium sulfate. , Sodium nitrate, aluminum chloride, calcium chloride, sodium chloride, calcium acetate, sodium acetate. These coagulants can be used alone or in combination of two or more. Among these coagulants, calcium acetate is preferable because it can reduce the amount of alkaline earth metals remaining in the rubber-containing graft polymer (A).

As described above, the sodium content of the butadiene rubber-containing graft polymer of the present invention is preferably 100 mass ppm or less, more preferably 50 mass ppm or less, still more preferably 30 mass ppm or less, from the viewpoint of molding processability.

[Resin composition]
The resin composition of the present invention contains the butadiene rubber-containing graft polymer of the present invention and a thermoplastic resin. The thermoplastic resin is not particularly limited, and examples thereof include aromatic polycarbonate resin, styrene resin, polyester resin, and polyolefin resin. The thermoplastic resin can be applied to a wide variety of resins such as engineering plastics, styrene resins, polyester resins, olefin resins, thermoplastic elastomers, biodegradable polymers, halogen-based polymers, and acrylic resins.

The engineering plastic is not particularly limited as long as it is a known various thermoplastic engineering plastic, and is a polyester polymer such as polyphenylene ether, polycarbonate, polyethylene terephthalate, polybutylene terephthalate, syndiotactic polystyrene, 6-nylon, 6,6. -Nylon-based polymers such as nylon, polyarylate, polyphenylene sulfide, polyetherketone, polyetheretherketone, polysulfone, polyethersulfone, polyamideimide, polyetherimide, polyacetal and the like can be exemplified.

Further, special styrene resins such as heat-resistant ABS and heat-resistant acrylic resins, which are highly heat-resistant and require melt fluidity, can also be exemplified as engineering plastics in the present invention. Among these, aromatic polycarbonate and polybutylene terephthalate, which are more required to develop strength, are more preferable. Examples of the aromatic polycarbonate include 4,4'-dioxydiarylalkane-based polycarbonates such as 4,4'-dihydroxydiphenyl-2,2-propane (that is, bisphenol A) -based polycarbonates.

Examples of the olefin resin include high-density polyethylene, medium-density polyethylene, low-density polyethylene, a copolymer of ethylene and other α-olefins; a copolymer of polypropylene, propylene and other α-olefins; polybutene, poly-4. -Methylpentene-1 and the like can be mentioned.

As thermoplastic elastomers, styrene-butadiene-styrene copolymer (SBS), styrene-isoprene-styrene copolymer (SIS), styrene-ethylene-butene copolymer (SEB), styrene-ethylene-propylene copolymer ( SEP), styrene-ethylene / butene-styrene elastomer (SEBS), styrene-ethylene / propylene-styrene elastomer (SEPS), styrene-ethylene / ethylene / propylene-styrene elastomer (SEEPS), styrene-butadiene Butylene-styrene elastomer (partial hydrogenation of styrene-butadiene-styrene elastomer: SBBS), partial hydrogenation of styrene-isoprene-styrene elastomer, styrene-isoprene-butadiene-styrene copolymer Sterylelastomers such as partial hydrogenated products, high molecular weight diols (polyesterdiol, polyetherdiol, polyesteretherdiol, polycarbonate diol, polyesterpolycarbonate diol, etc.), organic diisocyanates (4,4'-diphenylmethane diisocyanate as organic diisocyanates, Examples thereof include toluene diisocyanate, p-phenylenedi elastomer, xylylene diisocyanate, naphthalenediocyanate, hydrogenated 4,4'-diphenylmethane diisocyanate (4,4'-dicyclohexylmethane diisocyanate), isophorone diisocyanate, hexamethylene diisocyanate, and the like. Among the organic diisocyanates, 4,4'-diphenylmethane diisocyanate) and chain extenders (ethylene glycol, diethylene glycol, 1,4-butanediol, 1,5-pentanediol, 2-methyl-1,3-propanediol, 1, Urethane-based elastomer, ethylene-propylene rubber, produced by reacting 6-hexanediol, neopentyl glycol, 1,9-nonanediol, cyclohexanediol, 1,4-bis (β-hydroxyethoxy) benzene, etc.) Polyethylene-based elastomers such as ethylene-propylene-diene rubber, ethylene-vinyl acetate copolymer, butyl rubber, butadiene rubber, propylene-butene copolymer, ethylene-acrylic acid ester copolymer, polyamide-based elastomer, fluorine-based elastomer, chlorination Examples thereof include PE-based elastomers and acrylic-based elastomers.

Examples of the styrene resin include polystyrene, acrylonitrile-styrene copolymer, acrylonitrile-styrene-α-methylstyrene copolymer, acrylonitrile-methylmethacrylate-styrene-α-methylstyrene copolymer, ABS resin, AS resin, and MABS resin. MBS resin, AAS resin, AES resin, acrylonitrile-butadiene-styrene-α-methylstyrene copolymer, acrylonitrile-methylmethacrylate-butadiene-styrene-α-methylstyrene copolymer, styrene-maleic anhydride copolymer, styrene -Maleimide copolymer, styrene-N-substituted maleimide copolymer, acrylonitrile-styrene-N-substituted maleimide copolymer, acrylonitrile-butadiene-styrene-β-isopropenylnaphthalene copolymer, and acrylonitrile-methylmethacrylate-butadiene Examples thereof include a-styrene-α-methylstyrene-maleimide copolymer. These styrene resins can be used alone or in combination of two or more.

The polyester resin is a polymer composed of a polybasic acid and a polyhydric alcohol, and is not particularly limited as long as it has thermoplasticity. Examples of the polybasic acid include terephthalic acid, naphthaldicarboxylic acid, cyclohexyldicarboxylic acid or esters thereof, and examples of the polyhydric alcohol include ethylene glycol, propylene glycol, butanediol, pentanediol, neopentyl glycol and hexane. Examples thereof include diol, octanediol, decanediol, cyclohexanedimethanol, hydroquinone, bisphenol A, 2,2-bis (4-hydroxyethoxyphenyl) propane, 1,4-dimethyloltetrabromobenzene and TBA-EO. These polyester resins can be used individually by 1 type or in combination of 2 or more types. Further, the trade name "PETG" manufactured by Eastman Chemical is also preferably used.

In addition to the above-mentioned materials, the resin composition of the present invention contains various well-known additives such as stabilizers, flame retardants, flame retardant aids, hydrolysis inhibitors, and antistatic agents, as long as the object of the present invention is not impaired. It can contain an inhibitor, a foaming agent, a dye, a pigment and the like.

Examples of the blending method of each material when preparing the resin composition of the present invention include known blending methods, and are not particularly limited. Examples thereof include a method of mixing and kneading with a tumbler, a V-type blender, a super mixer, a nouter mixer, a Banbury mixer, a kneading roll, an extruder and the like.

Hereinafter, the present invention will be described in more detail with reference to Examples. The scope of the present invention is not limited to the following examples, and various modifications are possible as long as the gist of the present invention is not changed.

[Measurement method, calculation method]
<Volume average particle size, particle size distribution>
(Method using a capillary particle size measuring instrument)
The circle-equivalent diameter and volume of the particles in the latex were measured using a capillary particle size measuring device (capillary type submicron particle size distribution measuring device CHDF2000, manufactured by Matec Applied Sciences).
-Particles (%) with a particle size of 100 nm or less
The number of measured total particles and the number of particles having a circle-equivalent diameter of 100 nm or less were measured, and the ratio (%) of the number of particles having a circle-equivalent diameter of 100 nm or less to the total number of particles was calculated.
-Particles with a particle size of 400 nm or more Measure the number of particles with a circle-equivalent diameter of 100 nm or more and the number of particles with a circle-equivalent diameter of 400 nm or more, and the circle-equivalent diameter is 400 nm or more with respect to the number of particles with a circle-equivalent diameter of 100 nm or more. The ratio (%) of the number of particles was calculated.
-Volume average particle size (Dv)
The volume average particle diameter (Dv) was measured by excluding particles having a circle-equivalent diameter of 100 nm or less. Here, Dv is a 50% volume diameter.
Hereinafter, the Dv and the particle size distribution obtained by using the capillary type particle size measuring instrument may be referred to as “particle size distribution (capillary)”.

(Method using transmission electron microscope (TEM))
Powder obtained by drying latex was added to a polycarbonate resin (Iupilon (registered trademark) S-2000F, manufactured by Mitsubishi Engineering Plastics Co., Ltd.) in an amount of 3% by mass, and melt-kneaded to form a strand having a diameter of 3 mm. ..
The strands were stained with osmium tetroxide (OsO ₄ ) and microtomes were used to make ultrathin sections.
An ultrathin section was observed and imaged using a transmission electron microscope (H-7600, manufactured by Hitachi High-Technologies Corporation) to obtain an image.
The obtained image was subjected to image processing using an image analysis processing device (Image Pro Plus, manufactured by Nippon Roper Co., Ltd.).
-Particles with a particle size of 400 nm or more Measure the number of particles with a circle-equivalent diameter of 100 nm or more and the number of particles with a circle-equivalent diameter of 400 nm or more, and the circle-equivalent diameter is 400 nm or more with respect to the number of particles with a circle-equivalent diameter of 100 nm or more. The ratio (%) of the number of particles was calculated.
-Volume average particle size (Dv)
The volume average particle diameter (Dv) was measured by excluding particles having a circle-equivalent diameter of 100 nm or less. Here, Dv is a 50% volume diameter.
Hereinafter, the Dv and particle size distribution obtained by using TEM may be referred to as "particle size distribution (TEM)".

<Circularity>
The powder obtained by drying the rubber-containing graft polymer latex was ultrasonically cleaned in acetone to dissolve free PMMA that agglomerates the particles. The powder obtained by drying the rubber-containing graft polymer after washing with acetone was embedded in an epoxy resin and stained with osmium tetroxide (OsO ₄ ) to prepare ultrathin sections using a microtome.
An ultrathin section was observed and imaged using a transmission electron microscope (H-7600, manufactured by Hitachi High-Technologies Corporation) to obtain an image.
The obtained image was subjected to image processing using an image analysis processing device (Image Pro Plus, manufactured by Nippon Roper Co., Ltd.).
-Particles with a circularity of 0.75 or less The circle-equivalent diameter of the particles was measured, and the number of particles having a circular-equivalent diameter of 150 nm or more was measured to calculate the circularity. The ratio (%) of the number of particles having a circle-equivalent diameter of 150 nm or more and a circularity of 0.75 or less to the number of particles having a circle-equivalent diameter of 150 nm or more was calculated.

<Phosphorus content, sodium content>
The rubber-containing graft polymer latex was coagulated, washed, and dried, and 0.25 g of the obtained powder was weighed into a decomposition vessel.
8 mL of nitric acid was added to the decomposition vessel, and wet decomposition was performed by microwave (MARS5, manufactured by Astec).
After cooling, 2 mL of hydrofluoric acid was added to the decomposition vessel, and the mixture was treated again with microwaves. After the treatment, the solution was prepared by measuring up to 50 mL with distilled water.
This test solution was quantitatively analyzed using an ICP emission spectrometer (IRIS Intrepid 2 XSP, manufactured by Thermo) to determine the phosphorus content (unit: mass ppm) and sodium content (unit: mass ppm). .. The contents of phosphorus and sodium are both elemental contents.

<Fatty acid content>
The rubber-containing graft polymer latex was coagulated, washed, and then dried to obtain a powder obtained by methyl esterification treatment.
After the methyl esterification treatment, the masses of palmitic acid, oleic acid, stearic acid, dipotassium alkenylsuccinate and loginic acid were measured using a gas chromatograph (HP7890, manufactured by Agilent). From the measured mass and the mass of the sample, the fatty acid content was determined by mass percentage.

<Vinyl monomer composition of graft chain>
1. 1. Preparation of dry sample The following operations (1) to (9) were carried out to separate the rubber-containing graft polymer into a tetrahydrofuran-soluble component and a tetrahydrofuran-insoluble component.
(1) A solution composed of 1% by mass of the rubber-containing graft polymer and 99% by mass of tetrahydrofuran was prepared.
(2) The solution prepared in (1) was stirred for 1 hour.
(3) The solution stirred in (2) was centrifuged at 14,000 rpm for 60 minutes.
(4) The supernatant was extracted and placed in a flask.
(5) The same amount of organic solvent as in (1) was added to the precipitate (insoluble in tetrahydrofuran) again.
(6) The operations of (3) to (5) were repeated three times.
(7) The flask was set in a constant temperature bath having a temperature of 70 ° C., and the volatile matter was distilled off by an evaporator.
(8) The residue in the flask was dried at 80 ° C. for 8 hours using a steam dryer, and further dried at 65 ° C. for 6 hours using a vacuum dryer to obtain a dried sample of a tetrahydrofuran-soluble component.
(9) A container containing the precipitate was set in a constant temperature bath at 60 ° C., the organic solvent was volatilized, and then dried in a vacuum dryer at 65 ° C. for 6 hours to obtain a dried sample insoluble in tetrahydrofuran. It was.

2. 2. Quantification of Vinyl Monomer in Graft Chain The vinyl monomer in tetrahydrofuran-soluble component was quantified, and the composition of the graft chain was analyzed. The quantification of vinyl monomers was performed by pyrolysis gas chromatography-mass spectrometry (GC-MS).
However, only the caprolactone unit (CL) was extracted and quantified by the following method.

(Quantification of caprolactone units in the graft chain)
A dry graft chain sample was prepared and the composition was analyzed.
-Preparation of dried graft chain sample The procedure (1) to (9) below was followed.
(1) The insoluble content of tetrahydrofuran (THF) of the rubber-containing graft polymer was 6% by mass, and 94% by mass of a 1: 1 mixed solution of chloroform and methylene chloride was prepared and used as a dispersion solution.
(2) The solution was placed in an ozone absorption bottle and immersed in a dry ice-methanol solution prepared at -60 ° C or lower.
(3) Ozone gas generated from the ozone generator was blown into the absorption bottle to add ozone.
(4) After ozone was added (the absorption liquid turned blue), air was blown in to remove excess ozone.
(5) Adjust the reducing agent (sodium hydride) to a solution of 10% by mass and 90% by mass of methanol in a beaker, and stir with a magnetic stirrer. After dissolution, (4) an absorbent solution was added and stirred for 3 hours or more.
(6) After stirring, an aqueous hydrochloric acid solution (1: 1 = hydrochloric acid: water) having a mass corresponding to 1/5 of the mass of the solution (5) was added to the solution of (5), and the mixture was stirred for 3 hours or more.
(7) After stirring, the mixture is transferred to a separating funnel and separated into two layers. This lower layer was drained into an eggplant flask.
(8) The eggplant flask was set in a constant temperature bath at 65 ° C., and the volatile matter was distilled off by an evaporator.
(9) The residue in the eggplant flask was vacuum dried at 65 ° C. for 8 hours or more to obtain a “graft chain dried sample”.

-Composition analysis Analysis was performed according to the following operations (1) and (2).
(1) The dried graft chain sample is thermally decomposed at 500 ° C. using a thermal decomposition GC-MS (gas chromatography-mass spectrometer) under the conditions shown in 1) to 4) below, and the monomer composition ratio of the graft chain Was measured.
1) Column: Strong polarity column DP-FFAR (manufactured by Agilent Technologies), 30m x 0.25mm x 0.25μm
2) Column flow rate: 1.0 mL / min
3) Injection port, interface temperature: 230 ° C
4) Pyrolysis temperature: 500 ° C
(2) Composition analysis: Confirmed that 2-hydroxyethyl methacrylate and ε-caprolactone were detected as decomposition products of unsaturated fatty acid hydroxyalkyl ester-modified ε-caprolactone by thermal decomposition at 500 ° C. using thermal decomposition GC-MS. did.
Since the caprolactone unit (CL) is detected as ε-caprolactone, the peak derived from ε-caprolactone was considered to correspond to CL.
A copolymer of methyl methacrylate (MMA) and unsaturated fatty acid hydroxyalkyl ester-modified ε-caprolactone, which had a known composition ratio, was used as a standard polymer for calculating the amount of CL. The standard polymer was prepared by emulsion polymerization, and the polymerization rate was 99% or more. Further, the mass ratio of CL in the standard polymer was calculated from the molar mass of unsaturated fatty acid hydroxyalkyl ester-modified ε-caprolactone (244.3 g / mol) and the molar mass of ε-caprolactone (114.1 g / mol), and MMA. A calibration line showing the ratio of and CL was created. The correlation coefficient of the calibration curve was 0.99.

[Manufacture of coagulated and hypertrophied rubber-like polymer]
<Manufacturing of rubber-like polymer latex>
A rubbery polymer latex was produced as described below.

-Rubber polymer latex (a-1)
100 parts by mass of 1,3-butadiene, 0.4 parts by mass of tert-dodecyl mercaptan, 0.3 parts by mass of diisopropylbenzene hydroperoxide, 0.3 parts by mass of tetrasodium pyrophosphate salt, 0 parts of ferrous sulfate .004 parts by mass, 0.39 parts by mass of sodium sulfate, 0.4 parts by mass of glucose, 1.2 parts by mass of potassium rosinate and 1.2 parts by mass of potassium beef steat were charged in a pressure resistant autoclave and stirred. While reacting at 55 ° C. for 8 hours, a rubbery polymer latex (a-1) was obtained at a conversion rate of 95% by mass.
The volume average particle diameter of the obtained rubber-like polymer latex (a-1) was 93 nm.

-Rubber polymer latex (a-2)
100 parts by mass of 1,3-butadiene, 0.3 parts by mass of diisopropylbenzene hydroperoxide, 0.05 parts by mass of sodium formaldehyde sulfoxylate, 0.0012 parts by mass of ferrous sulfate, disodium ethylenediaminetetraacetate 0.008 part by mass and 1 part by mass of potassium oleate were charged in a pressure resistant autoclave and reacted at 65 ° C. for 10 hours with stirring to obtain a conversion rate of 95% by mass and a rubbery polymer latex (a-2). Got
The volume average particle diameter of the obtained rubber-like polymer latex (a-2) was 90 nm.

-Rubber polymer latex (a-3)
95 parts by mass of 1,3-butadiene, 5 parts by mass of styrene, 0.5 parts by mass of tert-dodecyl mercaptan, 1 part by mass of isopropylbenzene hydroperoxide, 0.4 parts by mass of sodium formaldehyde sulfoxylate, sulphate. 0.0005 parts by mass of monoiron, 0.0015 parts by mass of ethylenediaminetetraacetate disodium salt, 0.01 parts by mass of potassium hydroxide and 1.4 parts by mass of alkyldiphenyl ether disulfonic acid are charged in a pressure resistant autoclave and stirred. While reacting at 65 ° C. for 16 hours, a rubbery polymer latex (a-3) was obtained at a conversion rate of 95% by mass.
The volume average particle diameter of the obtained rubber-like polymer latex (a-3) was 170 nm.

<Agglutination and hypertrophy of rubber-like polymer latex>
As described below, a coagulation-enlarged treatment of the rubber-like polymer latex was performed to produce a coagulation-enlarged rubber-like polymer latex.

(Production Example 1) Cohesive and hypertrophied rubber-like polymer latex (A-1)
To the rubber-like polymer latex (a-1), 0.2 part by mass of sodium dodecylbenzenesulfonate (DBSNa) was added to 100 parts by mass of the solid content of the rubber-like polymer latex (a-1). Thoroughly stirred (DBSNa-latex mixture). Next, a 5 mass% phosphoric acid aqueous solution was added to the DBSNa-latex mixed solution by 4.8 parts by mass with respect to 100 parts by mass of the solid content of the rubbery polymer latex (a-1), and the mixture was stirred for 10 minutes. Retained while continuing (phosphoric acid-latex mixture). The pH of the phosphoric acid-latex mixed solution (pH after the bloating treatment) was measured after stirring and found to be pH 4.7. The phosphoric acid-latex mixed solution was neutralized with a 5 mass% potassium hydroxide aqueous solution (aggregated and enlarged rubber-like polymer latex (A-1)).
Volume average particle size (Dv) and particle size distribution (circle-equivalent particle size ratio of particles 100 nm or less (particle size 100 nm or less), yen-equivalent) of the obtained coagulated and enlarged rubbery polymer latex (A-1) The number ratio of particles having a particle size of 400 nm or more (particles having a particle size of 400 nm or more) was calculated by a capillary particle size measuring device, and is shown in the column of “particle size distribution (capillary)” in Table 1.

(Production Example 2) Cohesive and hypertrophied rubber-like polymer latex (A-2)
Aggregation hyperplasia except that the amount of 5% by mass phosphate aqueous solution added to 100 parts by mass of the solid content of the rubbery polymer latex (a-1) was changed from 4.8 parts by mass to 5.3 parts by mass. A coagulated and enlarged rubber-like polymer latex was produced in the same manner as the rubberized rubber-like polymer latex (A-1) (aggregated and enlarged rubber-like polymer latex (A-2)). The pH after the bloating treatment was measured and found to be pH 3.7.
Volume average particle size (Dv) and particle size distribution (circle-equivalent particle size ratio of particles 100 nm or less (particle size 100 nm or less), yen-equivalent) of the obtained coagulated and enlarged rubbery polymer latex (A-2) The number ratio of particles having a particle size of 400 nm or more (particles having a particle size of 400 nm or more) was calculated by a capillary particle size measuring device, and is shown in the column of “particle size distribution (capillary)” in Table 1.

(Production Example 3) Cohesive and hypertrophied rubber-like polymer latex (A-3)
Aggregation hyperplasia except that the amount of 5% by mass phosphate aqueous solution added to 100 parts by mass of the solid content of the rubbery polymer latex (a-1) was changed from 4.8 parts by mass to 4.6 parts by mass. A coagulated and enlarged rubber-like polymer latex was produced in the same manner as the rubberized rubber-like polymer latex (A-1) (aggregated and enlarged rubber-like polymer latex (A-3)). The pH after the hypertrophy treatment was measured and found to be pH 5.2.
Volume average particle size (Dv) and particle size distribution (circle-equivalent particle size ratio of particles of 100 nm or less (particles of 100 nm or less), yen-equivalent) of the obtained coagulated and enlarged rubbery polymer latex (A-3) The number ratio of particles having a particle size of 400 nm or more (particles having a particle size of 400 nm or more) was calculated by a capillary particle size measuring device, and is shown in the column of “particle size distribution (capillary)” in Table 1.

(Production Example 4) Cohesive and hypertrophied rubber-like polymer latex (A-4)
To the rubber-like polymer latex (a-2), 0.2 part by mass of sodium dodecylbenzenesulfonate (DBSNa) was added to 100 parts by mass of the solid content of the rubber-like polymer latex (a-2). Thoroughly stirred (DBSNa-latex mixture). Next, 5.0 parts by mass of a 5 mass% phosphoric acid aqueous solution was added to the DBSNa-latex mixed solution with respect to 100 parts by mass of the solid content of the rubbery polymer latex (a-2), and the mixture was stirred for 10 minutes. Retained while continuing (phosphoric acid-latex mixture). The pH of the phosphoric acid-latex mixed solution (pH after the bloating treatment) was measured after stirring and found to be pH 4.5. The phosphoric acid-latex mixed solution was neutralized with a 5 mass% sodium hydroxide aqueous solution (aggregated and enlarged rubber-like polymer latex (A-4)).
Volume average particle size (Dv) and particle size distribution (circle-equivalent particle size ratio of particles of 100 nm or less (particles of 100 nm or less), yen-equivalent) of the obtained coagulated and enlarged rubbery polymer latex (A-4) The number ratio of particles having a particle size of 400 nm or more (particles having a particle size of 400 nm or more) was calculated by a capillary particle size measuring device, and is shown in the column of “particle size distribution (capillary)” in Table 1.

(Production Example 5) Cohesive and hypertrophied rubber-like polymer latex (A-5)
The rubbery polymer latex (a-3) was used as it was. It has not been subjected to the coagulation and enlargement treatment and does not correspond to the coagulation and enlargement rubber-like polymer latex, but for convenience, it is referred to as the coagulation and enlargement rubber-like polymer latex (A-5).
Volume average particle size (Dv) and particle size distribution (circle-equivalent particle size 100 nm or less particles (particle size 100 nm or less), circle-equivalent particle size 400 nm) of coagulated and enlarged rubbery polymer latex (A-5) The number ratio of the above particles (particles having a particle size of 400 nm or more)) was calculated by a capillary type particle size measuring device, and is shown in the column of “particle size distribution (capillary)” in Table 1.

The meanings of the terms in the column of "particle size distribution (capillary)" in Table 1 are as follows.
Dv: Volume average particle size (nm) calculated by excluding particles with a circle-equivalent diameter of 100 nm or less
Particles with a particle size of 100 nm or less: Percentage of the number of particles with a circle-equivalent diameter of 100 nm or less (%)
Particles with a particle size of 400 nm or more: Ratio (%) of the number of particles with a circle-equivalent diameter of 400 nm or more to the number of particles with a circle-equivalent diameter of 100 nm or more.

[Example 1]
<Rubber-containing graft polymer latex>
(Manufacture of rubber-containing graft polymer latex)
80 parts by mass of the coagulated and enlarged rubbery polymer (A-1) was placed in a flask, and after nitrogen substitution, 0.05 parts by mass of sodium formaldehyde sulfoxylate (dihydrate) was added (mixture). .. While keeping the mixed solution at 60 ° C. (polymerization temperature), 20 parts by mass of methyl methacrylate (MMA) was added dropwise over 1 hour. After the dropping, the mixture was kept at the polymerization temperature for 1 hour to obtain a rubber-containing graft polymer latex (B-1).

(Volume average particle size, particle size distribution, circularity)
The volume average particle size, particle size distribution and circularity of the rubber-containing graft polymer latex (B-1) were calculated by the above-mentioned method, and in the “particle size distribution (capillary)” column of Table 2, “particle size distribution (TEM)”. And the column of "Circularity".

(Phosphorus content, sodium content, fatty acid content, vinyl monomer composition of graft chain, productivity)
The phosphorus content, sodium content, fatty acid content and vinyl monomer composition of the graft chain of the rubber-containing graft polymer latex (B-1) were calculated by the above-mentioned method, and the column of "phosphorus content" in Table 3 was calculated. , "Sodium content", "Fatty acid content" and "Vinyl monomer composition of graft chain".
The productivity was evaluated as A when the agglutination and hypertrophy treatment was performed during the production of the coagulation and hypertrophy rubber-like polymer latex, and as B when it was not performed. The evaluation results are shown in the "Productivity" column of Table 3.

<Resin composition>
(Manufacturing of resin composition)
The rubber-containing graft polymer latex (B-1) was coagulated with calcium acetate, washed, and then dried to obtain a rubber-containing graft polymer (B-1) as a powder.
The obtained rubber-containing graft polymer (B-1), aromatic polycarbonate resin (PC), and styrene acrylonitrile resin (SAN) are mixed in the blending amounts shown in Table 4, and melt-kneaded to form a resin composition. Obtained pellets of material.

(Impact test)
The pellets of the produced resin composition are supplied to an injection molding machine (SE100DU, manufactured by Sumitomo Heavy Industries, Ltd.), and have a cylinder temperature of 260 ° C. and a mold temperature of 60 ° C., and have a length of 80 mm, a width of 10 mm, and a thickness of 4 mm. A molded product was obtained. A test piece was prepared by carving a notch of TYPE A conforming to ISO 179-1: 2010 and ISO 2818: 2018 for this molded product. Using this test piece, Charpy impact strength (unit: kJ / m ² ) was measured at measurement temperatures of −30 ° C. and 23 ° C.
The measured Charpy impact strength is shown in the “Impact strength” column of Table 4.

[Example 2]
<Rubber-containing graft polymer latex>
(Manufacture of rubber-containing graft polymer latex)
20 parts by mass of methyl methacrylate (MMA), 19 parts by mass of methyl methacrylate (MMA) and unsaturated fatty acid hydroxyalkyl ester-modified ε-caprolactone represented by the following formula (4) (Plaxel FM1, manufactured by Daicel) (CL) The graft polymerization was carried out in the same manner as in Example 1 except that the mixture (MMA / CL) with 1 part by mass was changed to 20 parts by mass to obtain a rubber-containing graft polymer latex (B-2). ..
CH ₂ = C (CH ₃ ) COO (CH ₂ ) ₂ OCO (CH ₂ ) ₅ OH (4)

(Volume average particle size, particle size distribution, circularity)
The volume average particle size, particle size distribution and circularity of the rubber-containing graft polymer latex (B-2) were calculated by the above-mentioned method, and in the column of "particle size distribution (capillary)" in Table 2, "particle size distribution (TEM)". And the column of "Circularity".

(Phosphorus content, sodium content, fatty acid content, vinyl monomer composition of graft chain, productivity)
The phosphorus content, sodium content, fatty acid content and vinyl monomer composition of the graft chain of the rubber-containing graft polymer latex (B-2) were calculated by the above-mentioned method, and the column of "phosphorus content" in Table 3 was calculated. , "Sodium content", "Fatty acid content" and "Vinyl monomer composition of graft chain".
Productivity was evaluated in the same manner as in Example 1, and the evaluation results are shown in the “Productivity” column of Table 3.

<Resin composition>
(Manufacturing of resin composition)
The rubber-containing graft polymer latex (B-1) was changed to the rubber-containing graft polymer latex (B-2), and the rubber-containing graft polymer (B-1) was changed to the rubber-containing graft polymer (B-2). Pellets of the resin composition were produced in the same manner as in Example 1 except for the changes.

(Impact test)
Using the pellets of the produced resin composition, the Charpy impact strength (unit: kJ / m ² ) was measured in the same manner as in Example 1.
The measured Charpy impact strength is shown in the “Impact strength” column of Table 4.

[Example 3]
<Rubber-containing graft polymer latex>
(Manufacture of rubber-containing graft polymer latex)
The graft polymerization was carried out in the same manner as in Example 1 except that the aggregated and enlarged rubber-like polymer (A-1) was changed to the aggregated and enlarged rubber-like polymer (A-2), and the rubber-containing graft polymer was obtained. Latex (B-3) was obtained.

(Volume average particle size, particle size distribution, circularity)
The volume average particle size, particle size distribution and circularity of the rubber-containing graft polymer latex (B-3) were calculated by the above-mentioned method, and in the "particle size distribution (capillary)" column of Table 2, "particle size distribution (TEM)". And the column of "Circularity".

(Phosphorus content, sodium content, fatty acid content, vinyl monomer composition of graft chain, productivity)
The phosphorus content, sodium content, fatty acid content and vinyl monomer composition of the graft chain of the rubber-containing graft polymer latex (B-3) were calculated by the above-mentioned method, and the column of "phosphorus content" in Table 3 was calculated. , "Sodium content", "Fatty acid content" and "Vinyl monomer composition of graft chain".
Productivity was evaluated in the same manner as in Example 1, and the evaluation results are shown in the “Productivity” column of Table 3.

<Resin composition>
(Manufacturing of resin composition)
The rubber-containing graft polymer latex (B-1) was changed to the rubber-containing graft polymer latex (B-3), and the rubber-containing graft polymer (B-1) was changed to the rubber-containing graft polymer (B-3). Pellets of the resin composition were produced in the same manner as in Example 1 except for the changes.

(Impact test)
Using the pellets of the produced resin composition, the Charpy impact strength (unit: kJ / m ² ) was measured in the same manner as in Example 1.
The measured Charpy impact strength is shown in the “Impact strength” column of Table 4.

[Comparative Example 1]
<Rubber-containing graft polymer latex>
(Manufacture of rubber-containing graft polymer latex)
The graft polymerization was carried out in the same manner as in Example 1 except that the aggregated and enlarged rubber-like polymer (A-1) was changed to the aggregated and enlarged rubber-like polymer (A-3), and the rubber-containing graft polymer was obtained. Latex (B-4) was obtained.

(Volume average particle size, particle size distribution, circularity)
The volume average particle size, particle size distribution and circularity of the rubber-containing graft polymer latex (B-4) were calculated by the above-mentioned method, and in the column of "particle size distribution (capillary)" in Table 2, "particle size distribution (TEM)". And the column of "Circularity".

(Phosphorus content, sodium content, fatty acid content, vinyl monomer composition of graft chain, productivity)
The phosphorus content, sodium content, fatty acid content and vinyl monomer composition of the graft chain of the rubber-containing graft polymer latex (B-4) were calculated by the above-mentioned method, and the column of "phosphorus content" in Table 3 was calculated. , "Sodium content", "Fatty acid content" and "Vinyl monomer composition of graft chain".
Productivity was evaluated in the same manner as in Example 1, and the evaluation results are shown in the “Productivity” column of Table 3.

<Resin composition>
(Manufacturing of resin composition)
The rubber-containing graft polymer latex (B-1) was changed to the rubber-containing graft polymer latex (B-4), and the rubber-containing graft polymer (B-1) was changed to the rubber-containing graft polymer (B-4). Pellets of the resin composition were produced in the same manner as in Example 1 except for the changes.

(Impact test)
Using the pellets of the produced resin composition, the Charpy impact strength (unit: kJ / m ² ) was measured in the same manner as in Example 1.
The measured Charpy impact strength is shown in the “Impact strength” column of Table 4.

[Example 4]
<Rubber-containing graft polymer latex>
(Manufacture of rubber-containing graft polymer latex)
The rubber-containing graft polymer was subjected to graft polymerization in the same manner as in Example 1 except that the coagulated and hypertrophied rubber-like polymer (A-1) was changed to the coagulated and hypertrophied rubber-like polymer (A-4). Latex (B-5) was obtained.

(Volume average particle size, particle size distribution, circularity)
The volume average particle size, particle size distribution and circularity of the rubber-containing graft polymer latex (B-5) were calculated by the above-mentioned method, and in the column of "particle size distribution (capillary)" in Table 2, "particle size distribution (TEM)". And the column of "Circularity".

(Phosphorus content, sodium content, fatty acid content, vinyl monomer composition of graft chain, productivity)
The phosphorus content, sodium content, fatty acid content and vinyl monomer composition of the graft chain of the rubber-containing graft polymer latex (B-5) were calculated by the above-mentioned method, and the column of "phosphorus content" in Table 3 was calculated. , "Sodium content", "Fatty acid content" and "Vinyl monomer composition of graft chain".
Productivity was evaluated in the same manner as in Example 1, and the evaluation results are shown in the “Productivity” column of Table 3.

<Resin composition>
(Manufacturing of resin composition)
The rubber-containing graft polymer latex (B-1) was changed to the rubber-containing graft polymer latex (B-5), and the rubber-containing graft polymer (B-1) was changed to the rubber-containing graft polymer (B-5). Pellets of the resin composition were produced in the same manner as in Example 1 except that the changes were made and the mixture was neutralized with sodium hydroxide to pH = 7 after coagulation with sulfuric acid.

(Impact test)
Using the pellets of the produced resin composition, the Charpy impact strength (unit: kJ / m ² ) was measured in the same manner as in Example 1.
The measured Charpy impact strength is shown in the “Impact strength” column of Table 4.

[Comparative Example 2]
<Rubber-containing graft polymer latex>
(Manufacture of rubber-containing graft polymer latex)
The point that the aggregated and enlarged rubbery polymer (A-1) was changed to the aggregated and enlarged rubbery polymer (A-5), and 20 parts by mass of methyl methacrylate (MMA) was changed to 18 parts by mass of methyl methacrylate (MMA). The graft polymerization was carried out in the same manner as in Example 1 except that the mixture (MMA / BA) of 2 parts by mass of butyl acrylate (BA) was changed to 20 parts by mass, and the rubber-containing graft polymer latex (B) was carried out. -6) was obtained.

(Volume average particle size, particle size distribution, circularity)
The volume average particle size, particle size distribution and circularity of the rubber-containing graft polymer latex (B-6) were calculated by the above-mentioned method, and in the column of "particle size distribution (capillary)" in Table 2, "particle size distribution (TEM)". And the column of "Circularity".

(Phosphorus content, sodium content, fatty acid content, vinyl monomer composition of graft chain, productivity)
The phosphorus content, sodium content, fatty acid content and vinyl monomer composition of the graft chain of the rubber-containing graft polymer latex (B-6) were calculated by the above-mentioned method, and the column of "phosphorus content" in Table 3 was calculated. , "Sodium content", "Fatty acid content" and "Vinyl monomer composition of graft chain".
Productivity was evaluated in the same manner as in Example 1, and the evaluation results are shown in the “Productivity” column of Table 3.

<Resin composition>
(Manufacturing of resin composition)
The rubber-containing graft polymer latex (B-1) was changed to the rubber-containing graft polymer latex (B-6), and the rubber-containing graft polymer (B-1) was changed to the rubber-containing graft polymer (B-6). Pellets of the resin composition were produced in the same manner as in Example 1 except for the changes.

(Impact test)
Using the pellets of the produced resin composition, the Charpy impact strength (unit: kJ / m ² ) was measured in the same manner as in Example 1.
The measured Charpy impact strength is shown in the “Impact strength” column of Table 4.

The meanings of the terms in the "particle size distribution (capillary)" column, the "particle size distribution (TEM)" column, and the "circularity" column in Table 2 are as follows.
Dv [nm]: Volume average particle size (nm) calculated by excluding particles with a circle-equivalent diameter of 100 nm or less.
Particles with a particle size of 100 nm or less [%]: Percentage of the number of particles with a circle-equivalent diameter of 100 nm or less (%)
Particles with a particle size of 400 nm or more [%]: Ratio of the number of particles with a circle-equivalent diameter of 400 nm or more to the number of particles with a circle-equivalent diameter of 100 nm or more (%)
Particles with a circularity of 0.75 or less [%]: Ratio of the number of particles with a circularity of 0.75 or less to the number of particles with a circle-equivalent diameter of 150 nm or more (%)

The meanings of the symbols in the column of "vinyl monomer composition of graft chain" in Table 3 are as follows.
MMA: Methyl Methacrylate (Acryester M, manufactured by Mitsubishi Chemical Corporation)
CL: Unsaturated fatty acid hydroxyalkyl ester modified ε-caprolactone (Plaxel FM1, manufactured by Daicel)
BA: Butyl acrylate (Acrylate B, manufactured by Mitsubishi Chemical Corporation)

In Table 4, the rubber-containing graft polymer shows a rubber-containing graft polymer obtained by coagulating a rubber-containing graft polymer latex, washing it, and then drying it.
The abbreviations in Table 4 have the following meanings.
PC: Aromatic polycarbonate resin (Iupilon (registered trademark) S-2000F, manufactured by Mitsubishi Engineering Plastics) Viscosity average molecular weight (nominal value) = 22000
SAN: Styrene acrylonitrile resin (AP-H, manufactured by Techno-UMG) Acrylonitrile (AN) ratio (nominal value) = around 26%, mass average molecular weight (nominal value) = around 110,000

[Test Examples 1 to 4]
(Manufacturing of resin composition)
The rubber-containing graft polymer latex (B-1) or the rubber-containing graft polymer latex (B-5) is coagulated with calcium acetate, washed, and then dried to obtain the rubber-containing graft polymer (B-1) or rubber. The containing graft polymer (B-5) was obtained as a powder.
The obtained rubber-containing graft polymer (B-1) or rubber-containing graft polymer (B-5), a polycarbonate resin (PC), and a polyethylene terephthalate resin (PET) or a polybutylene terephthalate resin (PBT) are used. The mixture was mixed in the blending amounts shown in Table 5 and melt-kneaded to obtain pellets of the resin composition of each test example.

(Tensile test)
In each test example, the manufactured thermoplastic resin pellets were supplied to an injection molding machine (SE100DU, manufactured by Sumitomo Heavy Industries, Ltd.), and test pieces were prepared at a cylinder temperature of 260 ° C. and a mold temperature of 60 ° C. Using this test piece, a tensile test was performed at a tensile speed of 50 mm / min in accordance with ISO 527-1: 2012, and the elongation at break (unit:%) was measured. The average (average breaking point elongation) and standard deviation of the breaking point elongations of the three test pieces were calculated.
The calculated breaking point elongation is shown in the "Average breaking point elongation" column of Table 5, and the calculated standard deviation is shown in the "Standard deviation" column of Table 5, respectively.

In Table 5, the rubber-containing graft polymer shows a rubber-containing graft polymer obtained by coagulating a rubber-containing graft polymer latex, washing it, and then drying it.
The abbreviations in Table 5 have the following meanings.
PC: Aromatic polycarbonate resin (Iupilon (registered trademark) S-2000F, manufactured by Mitsubishi Engineering Plastics) Viscosity average molecular weight (nominal value) = 22000
PET: Polyethylene terephthalate resin (TRN-8550FF, manufactured by Teijin Limited)
PBT: Polybutylene terephthalate resin (Novaduran (registered trademark) 5010R5, manufactured by Mitsubishi Engineering Plastics)

[Explanation of results]
As shown in Table 2, in the rubber-containing graft polymers of Examples 1 to 5, the ratio of the number of particles having a circle-equivalent diameter of 400 nm or more to the number of particles having a circle-equivalent diameter of 100 nm or more is 5% or less (““ "Particles with a particle size of 400 nm or more" in the "Particle size distribution (TEM)" column), and the volume average particle size calculated by excluding particles with a circle-equivalent diameter of 100 nm or less is in the range of 150 to 250 nm ("particle size distribution"). (TEM) ”column“ Dv ”).
On the other hand, in the rubber-like graft polymer of Comparative Example 1, the ratio of the number of particles having a circle-equivalent diameter of 400 nm or more to the number of particles having a circle-equivalent diameter of 100 nm or more exceeds 5% (“particle size distribution (TEM”). ) ”), And the volume average particle size calculated by excluding particles with a circle-equivalent diameter of 100 nm or less was outside the range (300 nm) of 150 to 250 nm (“300 nm). "Dv") in the "Particle size distribution (TEM)" column.
As shown in Table 4, the impact strength of the molded product of the resin composition produced by using the rubber-containing graft polymers of Examples 1 to 5 was excellent at both 23 ° C and -30 ° C (“impact test”). Column). On the other hand, the impact strength of the molded product of the resin composition produced by using the rubber-containing graft polymer of Comparative Example 1 was inferior at both 23 ° C. and −30 ° C.
In Comparative Example 2, the particle size of the rubber-like polymer was increased by emulsion polymerization without coagulation and hypertrophy. The productivity of the rubber-containing graft polymer is inferior to that of Examples 1 to 4 in which the particle size of the rubber-like polymer is increased by the coagulation and enlargement treatment.

As shown in Table 5, it can be seen that by suppressing the content of sodium in the rubber-containing graft polymer, the elongation at break and its standard deviation during the tensile test are reduced and the moldability is improved. From this, it can be seen that by reducing the sodium content, the decomposition reaction or transesterification reaction between the polyethylene terephthalate resin and the aromatic polycarbonate resin is suppressed, and the molding processability is improved.

Claims (17)

A butadiene rubber-containing graft polymer that satisfies the following conditions (1), (2) and (3).
(1) The ratio of the number of particles having a circle-equivalent diameter of 400 nm or more to the number of particles having a circle-equivalent diameter of 100 nm or more is 5% or less.
(2) The volume average particle diameter calculated by excluding particles having a circle-equivalent diameter of 100 nm or less is 150 to 250 nm.
(3) The ratio of the number of particles having a circle-equivalent diameter of 150 nm or more and a circularity of 0.75 or less to the number of particles having a circle-equivalent diameter of 150 nm or more is 70% or more. The butadiene rubber-containing graft polymer according to claim 1, which contains 200 mass ppm or more of a phosphorus element. The butadiene rubber-containing graft polymer according to claim 1 or 2, which contains 100 mass ppm or less of sodium element. The butadiene rubber-containing graft polymer according to any one of claims 1 to 3, which contains at least 1% by mass in total of one or more selected from the group consisting of fatty acids and salts thereof. The unit according to any one of claims 1 to 4, wherein 95% by mass or more of the total mass of the units derived from the vinyl monomer of the graft chain of the butadiene rubber-containing graft polymer is the unit derived from methyl methacrylate. Polybutadiene rubber-containing graft polymer. When the butadiene rubber-containing graft polymer is mixed with an organic solvent and separated into an organic solvent-insoluble component and an organic solvent-soluble component, the organic solvent-insoluble component contains a graft chain of the butadiene rubber-containing graft polymer, and the above. The butadiene rubber-containing graft polymer according to any one of claims 1 to 5, wherein the graft chain contains a caprolactone unit. A rubber latex containing a butadiene rubber and a vinyl monomer are mixed at a mass ratio of the butadiene rubber / the vinyl monomer = 45/55 to 90/10, and the vinyl monomer is graft-polymerized on the butadiene rubber. The butadiene rubber-containing graft polymer according to any one of claims 1 to 6 thus obtained. The butadiene rubber-containing graft polymer according to claim 7, which is obtained by graft-polymerizing the vinyl monomer on the butadiene rubber and then coagulating with calcium acetate. An aqueous phosphoric acid solution was added in an amount of 0.1 to 10 parts by mass in terms of solid content with respect to 100 parts by mass of the solid content of the rubber latex containing butadiene rubber to coagulate and enlarge the butadiene rubber.
The obtained aggregated and enlarged rubber-like polymer latex containing the aggregated and enlarged butadiene rubber and the vinyl monomer are combined with the solid content of the aggregated and enlarged rubbery polymer latex / the vinyl monomer = 45 / 55-90. Mix at a mass ratio of 1/10 and
Obtained by graft-polymerizing the vinyl monomer on the coagulated and hypertrophied butadiene rubber.
A butadiene rubber-containing graft polymer containing 2.5% by mass or less of particles having a volume average particle diameter of 150 to 220 nm and a circle-equivalent diameter of 400 nm or more. The butadiene rubber-containing graft polymer according to claim 9, which contains 8% by mass or less of particles having a circle-equivalent diameter of 100 nm or less. The butadiene rubber-containing graft polymer according to claim 9 or 10, which is mixed at a mass ratio of solid content of the coagulated and enlarged rubber-like polymer latex / vinyl monomer = 45/55 to 85/15. The butadiene rubber-containing graft polymer according to any one of claims 9 to 11, wherein the vinyl monomer contains 95% by mass or more of methyl methacrylate. The butadiene rubber-containing graft polymer according to any one of claims 9 to 12, wherein the vinyl monomer contains caprolactone. The butadiene rubber-containing graft polymer according to any one of claims 9 to 13, which contains 1 part by mass or more of a fatty acid-based emulsifier with respect to 100 parts by mass of the butadiene rubber-containing graft polymer. A resin composition containing the butadiene rubber-containing graft polymer according to any one of claims 1 to 14 and a thermoplastic resin. The resin composition according to claim 15, wherein the thermoplastic resin contains an aromatic polycarbonate resin. The resin composition according to claim 15 or 16, wherein the thermoplastic resin contains a polyester resin.