Resin composition, method for manufacturing the same, and molded article using the same

Abstract

The present invention aims to provide a resin composition with good impact resistance, surface smoothness, color development, and molded product appearance, and a method for producing the same. The invention provides a graft copolymer (A) obtained by graft copolymerizing a monomer mixture (a) containing at least an aromatic vinyl monomer (a1) and a vinyl cyanide monomer (a2) in the presence of an acrylic rubber polymer (R) obtained by copolymerizing an alkyl acrylate monomer (r1) and a polyfunctional monomer (r2), and... A resin composition comprising a vinyl copolymer (B) obtained by copolymerizing a monomer mixture (b) containing at least an aromatic vinyl monomer (b1) and a vinyl cyanide monomer (b2), The present invention relates to a resin composition characterized in that the total amount of anionic surfactants contained in the resin composition is 5000 ppm (mass / mass) or less of the total amount of the resin composition, and the combined proportion of a sulfosuccinate compound (E) represented by the following chemical formula [1] and disproportionated rosin (F) contained in the resin composition is 2000 ppm (mass / mass) or less of the total amount of the resin composition, and the ratio of the sulfosuccinate compound (E) to disproportionated rosin (F) is 10:90 to 30:70 by mass ratio (sulfosuccinate compound (E): disproportionated rosin (F)), and also relates to a method for producing the resin composition. [Formula 1] TIFF2026519162000012.tif216132(R is an alkyl or alkenyl group having 8 to 22 carbon atoms, AO is an oxyalkylene group having 2 or 3 carbon atoms, n is an integer from 0 to 20, M and N are independently hydrogen, an alkali metal, or an alkaline earth metal, p is 1 if M is hydrogen or an alkali metal, and 1 / 2 if M is an alkaline earth metal, and q is 1 if N is hydrogen or an alkali metal, and 1 / 2 if N is an alkaline earth metal.)

Description

[Technical Field]

[0001] The present invention relates to a resin composition useful for resin molded articles used in home appliances, communication-related equipment, general merchandise, and automotive materials, and to a method for producing the same. [Background technology]

[0002] ABS resin, produced by polymerizing diene-based rubber polymers, aromatic vinyl monomers, vinyl cyanide monomers, methacrylic acid ester monomers, etc., offers excellent impact resistance, moldability, and appearance, and is widely used in various applications such as office equipment, home appliances, and general merchandise. However, because ABS resin has many chemically unstable double bonds in the main chain of the polymer, it is prone to degradation by ultraviolet rays and has poor weather resistance, making it unsuitable for outdoor use. Therefore, methods using saturated rubber polymers that do not have double bonds in the main chain have been proposed, and ASA resin, which uses acrylic rubber, is a well-known example of this, offering excellent weather resistance and being widely used, mainly in vehicle applications.

[0003] Patent Document 1 proposes a resin composition in which an organic silicone oil is added to a composition using a specific acrylic rubber and / or silicone rubber as a method to improve impact resistance, color development, weather resistance, rigidity, heat resistance, and processability.

[0004] On the other hand, styrene-based thermoplastic resin compositions containing heat-resistant vinyl copolymers are widely used in automotive applications, particularly for lamp housings, due to their excellent heat resistance in molded products. Lamp housings are typically subjected to secondary processing such as painting, metal deposition, and plating to enhance the brightness of vehicle lighting. To obtain a beautiful appearance after secondary processing such as painting, metal deposition, or plating, the surface of the molded product must be smooth before secondary processing. Undercoat treatment is usually performed to smooth the surface of the molded product before secondary processing. If the molded product is smooth, the metal layer can be formed directly without forming an undercoat layer, leading to a reduction in product cost. As a method for forming a metal layer without forming an undercoat layer, the so-called "direct deposition method" is known and has become commonly used in recent years. Therefore, resin compositions used to form lamp housings and the like are required to provide molded products with excellent smoothness.

[0005] Patent Document 2 proposes an acrylic rubber-reinforced copolymer resin obtained by polymerizing a vinyl monomer containing an aromatic vinyl compound and a vinyl cyanide compound in the presence of an acrylic rubber polymer obtained by emulsion polymerization using an emulsifier containing an alkyl sulfonate and a rosinate, as a method to improve vibration welding, hot plate welding properties, and the brightness of the lamp after vapor deposition.

[0006] However, in all of these methods, the balance between impact resistance, surface smoothness, color development, and molded product appearance (influence of volatile components on appearance) in the resin composition was insufficient, which sometimes limited its application to a wide range of uses. [Prior art documents] [Patent Documents]

[0007] [Patent Document 1] Japanese Patent Publication No. 2001-031830 [Patent Document 2] Japanese Patent Application Publication No. 2006-131677 [Overview of the Initiative] [Problems that the invention aims to solve]

[0008] The present invention aims to solve the problems of the prior art described above, and specifically to provide a resin composition with good impact resistance, surface smoothness, color development, and molded product appearance, as well as a method for producing the same. [Means for solving the problem]

[0009] As a result of diligent research to achieve the above objective, the present inventors have discovered that a resin composition comprising a vinyl copolymer obtained by copolymerizing a vinyl monomer mixture and an acrylic rubber polymer-containing graft copolymer, preferably containing a heat-resistant vinyl copolymer, obtained by a manufacturing method using a specific emulsifier in a specific range, exhibits excellent impact resistance and good surface smoothness, color development, and molded product appearance, thus leading to the present invention.

[0010] In other words, one aspect of the present invention is as follows: (1) Step 1: A step to obtain a graft copolymer (A) by performing the following steps 1-A to 1-C in this order. Step 1-A: A step to obtain a latex rubber polymer (R) by copolymerizing 100 parts by mass of a monomer mixture (r) consisting of 97 to 99.5 parts by mass of an alkyl acrylate monomer (r1) and 0.5 to 3 parts by mass of a polyfunctional monomer (r2) in the presence of 0.15 to 0.45 parts by mass of a sulfosuccinate compound (E) represented by the following chemical formula [1] and 1.5 to 3 parts by mass of disproportionating rosin (F) as an emulsifier.

[0011] [ka]

[0012] (R is an alkyl or alkenyl group having 8 to 22 carbon atoms, AO is an oxyalkylene group having 2 or 3 carbon atoms, n is an integer from 0 to 20, M and N are independently hydrogen, an alkali metal, or an alkaline earth metal, p is 1 if M is hydrogen or an alkali metal, and 1 / 2 if M is an alkaline earth metal, and q is 1 if N is hydrogen or an alkali metal, and 1 / 2 if N is an alkaline earth metal.) Step 1-B: In the presence of the latex of the rubbery polymer (R), a monomer mixture (a) containing at least an aromatic vinyl monomer (a1) and a vinyl cyanide monomer (a2) is graft copolymerized onto the rubbery polymer (R) to obtain the latex of the graft copolymer (A). Step 1-C: A step of contacting the latex of the graft copolymer (A) with an acid, then neutralizing it with an alkali, washing it with water, and dehydrating it to obtain the graft copolymer (A). Step 2: A process of copolymerizing a monomer mixture (b) containing at least an aromatic vinyl monomer (b1) and a vinyl cyanide monomer (b2) to obtain a vinyl copolymer (B), and, Step 3: A step of mixing the graft copolymer (A) obtained in Step 1 and the vinyl copolymer (B) obtained in Step 2. A method for producing a resin composition comprising the following: the proportion of the total amount of anionic surfactant contained in the resin composition is 5000 ppm (mass / mass) or less of the total amount of the resin composition, and the proportion of the sulfosuccinate compound (E) represented by the chemical formula [1] and disproportionated rosin (F) contained in the resin composition together is 2000 ppm (mass / mass) or less of the total amount of the resin composition. (2) The method for producing the resin composition according to (1), further comprising performing the following step 4 to obtain a heat-resistant vinyl copolymer (C), and mixing the obtained heat-resistant vinyl copolymer (C) together with the graft copolymer (A) and vinyl copolymer (B) in step 3 to obtain a resin composition. Step 4: A process to copolymerize a monomer mixture (c) containing at least an aromatic vinyl monomer (c1) and a maleimide monomer (c2) to obtain a heat-resistant vinyl copolymer (C). (3) In the step 1-A, the sulfosuccinic acid compound (E) and disproportionated rosin (F) are used in a mass ratio of 9:91 to 30:70 (sulfosuccinic acid compound (E): disproportionated rosin (F)), and the method for producing the resin composition according to (1) or (2) is characterized thereby. (4) A graft copolymer (A) obtained by graft copolymerizing a monomer mixture (a) containing at least an aromatic vinyl monomer (a1) and a vinyl cyanide monomer (a2) in the presence of an acrylic rubber polymer (R) obtained by copolymerizing an alkyl acrylate monomer (r1) and a polyfunctional monomer (r2), and a vinyl copolymer (B) obtained by copolymerizing a monomer mixture (b) containing at least an aromatic vinyl monomer (b1) and a vinyl cyanide monomer (b2), wherein the resin composition contains: The total amount of the anionic surfactant contained in the resin composition is 5000 ppm (mass / mass) or less of the total amount of the resin composition, and the total amount of the sulfosuccinic acid compound (E) and disproportionated rosin (F) represented by the following chemical formula [1] contained in the resin composition is 2000 ppm (mass / mass) or less of the total amount of the resin composition, and the ratio of the sulfosuccinic acid compound (E) to the disproportionated rosin (F) is in a mass ratio of 10:90 to 30:70 (sulfosuccinic acid compound (E): disproportionated rosin (F)).

[0013] [Chemical formula]

[0014] (R is an alkyl group or alkenyl group having 8 to 22 carbon atoms, AO is an oxyalkylene group having 2 or 3 carbon atoms, n is an integer of 0 to 20, M and N are each independently hydrogen, an alkali metal or an alkaline earth metal, p is 1 when M is hydrogen or an alkali metal, p is 1 / 2 when M is an alkaline earth metal, q is 1 when N is hydrogen or an alkali metal, and q is 1 / 2 when N is an alkaline earth metal.) (5) Further, it contains a heat-resistant vinyl copolymer (C) obtained by copolymerizing a monomer mixture (c) containing at least an aromatic vinyl monomer (c1) and a maleimide monomer (c2), and is characterized in that it is the resin composition according to (4). (6) A resin composition obtained by the method for producing a resin composition according to any one of (1) to (3), or a molded article obtained by molding the resin composition according to (4) or (5).

Advantages of the Invention

[0015] According to the present invention, it is possible to provide a resin composition having good impact resistance, surface smoothness, coloring property, and appearance of a molded article, and a method for producing the same.

Brief Description of the Drawings

[0016] [Figure 1] Image of a transmission electron microscope (TEM) of a resin composition produced by the method described in Comparative Example 2

Embodiments for Carrying Out the Invention

[0017] The resin composition of the present invention contains at least the following components. Component 1: A graft copolymer (A) obtained by graft copolymerizing a monomer mixture (a) containing at least an aromatic vinyl monomer (a1) and a vinyl cyanide monomer (a2) in the presence of an acrylic rubber polymer (R) obtained by copolymerizing an alkyl acrylate monomer (r1) and a polyfunctional monomer (r2). Component 2: A vinyl copolymer (B) obtained by copolymerizing a monomer mixture (b) containing at least an aromatic vinyl monomer (b1) and a vinyl cyanide monomer (b2). Component 3: A sulfosuccinic acid compound (E) represented by the following chemical formula [1].

[0018]

Chemical formula

[0019] (R is an alkyl or alkenyl group having 8 to 22 carbon atoms, AO is an oxyalkylene group having 2 or 3 carbon atoms, n is an integer from 0 to 20, M and N are independently hydrogen, an alkali metal, or an alkaline earth metal, p is 1 if M is hydrogen or an alkali metal, and 1 / 2 if M is an alkaline earth metal, and q is 1 if N is hydrogen or an alkali metal, and 1 / 2 if N is an alkaline earth metal.) Ingredient 4: Disproportionate rosin (F).

[0020] As described later, the resin composition of the present invention may contain other components as needed. Preferably, it may also contain a heat-resistant vinyl copolymer (C) obtained by copolymerizing a monomer mixture (c) containing at least an aromatic vinyl monomer (c1) and a maleimide monomer (c2).

[0021] In the resin composition of the present invention, the function of each component is not necessarily clear, but the inventors understand it as follows: The graft copolymer (A) can improve the moldability of the resin composition, improve the impact resistance, surface smoothness, and color development of the molded article, and enhance the appearance of the molded article. The vinyl copolymer (B) can improve the fluidity of the resin composition, improve the color development of the molded article, and enhance the appearance of the molded article. The sulfosuccinate compound (E) can improve the surface smoothness and color development of the molded article and enhance the appearance of the molded article. The disproportionate rosin (F) can improve the impact resistance of the molded article. Furthermore, the heat-resistant vinyl copolymer (C) can impart heat resistance to the molded article.

[0022] The following provides a more detailed explanation of the manufacturing methods for obtaining each component, including specific examples.

[0023] The graft copolymer (A) (component 1) used in the present invention can be produced by carrying out steps 1-A to 1-C in the order described below.

[0024] [(Step 1-A) A step to obtain a latex rubber polymer (R) by copolymerizing 100 parts by mass of a monomer mixture (r) consisting of 97 to 99.5 parts by mass of an alkyl acrylate monomer (r1) and 0.5 to 3 parts by mass of a polyfunctional monomer (r2) in the presence of 0.15 to 0.45 parts by mass of a sulfosuccinate compound (E) represented by the above chemical formula [1] and 1.5 to 3 parts by mass of disproportionating rosin (F) as an emulsifier].

[0025] The alkyl acrylate monomer (r1) for obtaining the rubbery polymer (R) is preferably one having an alkyl group with 1 to 10 carbon atoms, such as methyl acrylate, ethyl acrylate, n-butyl acrylate, t-butyl acrylate, and octyl acrylate. Two or more of these may be used. Among these, n-butyl acrylate is preferred.

[0026] The polyfunctional monomer (r2) for obtaining the rubbery polymer (R) is not particularly limited as long as it can polymerize with the alkyl acrylate monomer (r1) and has two or more functional groups. Examples of functional groups include groups having a carbon-carbon double bond, such as allyl groups and (meth)acryloyl groups. Examples of polyfunctional monomers (r2) include allyl compounds such as allyl acrylate, allyl methacrylate, diallyl maleate, triallyl cyanurate, and triallyl isocyanurate, and di(meth)acrylic acid ester compounds such as divinylbenzene, ethylene glycol dimethacrylate, diethylene glycol dimethacrylate, and propylene glycol dimethacrylate. Two or more of these may be used. Among these, allyl methacrylate is preferred.

[0027] The rubbery polymer (R) used in the present invention is obtained by copolymerizing 100 parts by mass of a monomer mixture (r) consisting of 97 to 99.5 parts by mass of an acrylic acid ester monomer (r1) and 0.5 to 3 parts by mass of a polyfunctional monomer (r2). If the amount of acrylic acid ester monomer (r1) is less than 97 parts by mass, or the amount of polyfunctional monomer (r2) is greater than 3 parts by mass, the degree of crosslinking of the rubbery polymer (R) increases. As a result, the rubbery polymer (R) hardens, and when stress is applied, stress concentrates in the parts with small molecular weights between crosslinking points, causing the molecular chains to break and reducing the impact resistance of the molded product. In the monomer mixture (r), it is preferable that the content of acrylic acid ester monomer (r1) is 98 parts by mass or more and the content of polyfunctional monomer (r2) is 2 parts by mass or less, and it is even more preferable that the content of acrylic acid ester monomer (r1) exceeds 98.5 parts by mass and the content of polyfunctional monomer (r2) is less than 1.5 parts by mass. Although the monomer mixture (r) is a mixture of acrylic acid ester monomer (r1) and polyfunctional monomer (r2), this does not prevent the use of other components during polymerization, as long as it does not hinder the objective of the present invention.

[0028] On the other hand, if the amount of acrylic acid ester monomer (r1) exceeds 99.5 parts by mass, or if the amount of polyfunctional monomer (r2) is less than 0.5 parts by mass, per 100 parts by mass of the monomer mixture (r), the degree of swelling of the rubbery polymer increases. As a result, the particles of the graft copolymer (A) tend to form aggregate structures, and uncrosslinked molecular chains dissolve into the resin composition, reducing the surface smoothness and color development of the molded product. In the monomer mixture (r), the amount of acrylic acid ester monomer (r1) is preferably 99.4 parts by mass or less, and more preferably 99.2 parts by mass or less. Furthermore, the amount of polyfunctional monomer (r2) is preferably 0.6 parts by mass or more, and more preferably 0.8 parts by mass or more.

[0029] In the present invention, there are no particular restrictions on the volume-average particle diameter of the rubbery polymer (R), but from the viewpoint of impact resistance, surface smoothness, and color development of the molded article containing the rubbery polymer (R) graft copolymer (A) and vinyl copolymer (B), it is preferably in the range of 0.05 to 1 μm. More preferably, it is in the range of 0.05 to 0.5 μm, even more preferably in the range of 0.05 to 0.2 μm, and most preferably in the range of 0.05 to 0.15 μm.

[0030] In the present invention, there are no particular restrictions on the standard deviation of the volume-average particle size of the rubbery polymer (R), however, from the viewpoint of surface smoothness and color development of the molded article containing a graft copolymer (A) using the rubbery polymer (R) and a vinyl copolymer (B), it is preferably 0.05 μm or less, more preferably 0.03 μm or less, and even more preferably 0.01 μm or less.

[0031] Furthermore, the volume-average particle size of the rubbery polymer (R) can be adjusted to a desired range by, for example, the amount of water, emulsifier, and polymerization initiator used in polymerization. In addition, within the preferred range of the volume-average particle size and its standard deviation of the rubbery polymer (R) described above, it may be adjusted to a desired range by enlargement through the addition of acidic aqueous solutions such as acetic acid, phosphoric acid, and sulfuric acid, or by adding acid group-containing latex. Here, acid group-containing latex is a latex made using unsaturated acid monomers and unsaturated carboxylate alkyl ester monomers.

[0032] Furthermore, the volume-average particle size and its standard deviation of the rubbery polymer (R) can be measured by dispersing the latex of the rubbery polymer (R) in water and using a laser scattering diffraction particle size distribution analyzer.

[0033] Preferably, the weight-average molecular weight of the acetone-soluble component in the rubbery polymer (R), in terms of styrene equivalent, is 30,000 to 60,000. The acetone-soluble component in the rubbery polymer (R) mainly consists of linear polymers of uncrosslinked alkyl acrylate monomers, which are considered to indirectly represent the molecular chain length constituting the rubbery polymer (R). If the weight-average molecular weight of the acetone-soluble component in the rubbery polymer (R), in terms of styrene equivalent, is 30,000 or more, the impact resistance can be further improved while maintaining the surface smoothness of the molded product. Furthermore, as mentioned above, these linear polymers can be a factor that impairs the surface smoothness of the molded product, but this is particularly noticeable when these linear polymers are long-chain. Therefore, if the weight-average molecular weight of the acetone-soluble component in the rubbery polymer (R), in terms of styrene equivalent, is 60,000 or less, the surface smoothness can be further improved while maintaining the impact resistance of the molded product.

[0034] Here, the weight-average molecular weight of the acetone-soluble component in the rubbery polymer (R), in terms of styrene, can be determined by the following method.

[0035] Specifically, approximately 1 g of rubbery polymer (R) is impregnated with approximately 80 ml of acetone for approximately 12 hours. Next, the acetone dispersion of this rubbery polymer (R) is filtered, and the filtrate is concentrated using a rotary evaporator to collect the acetone-soluble components from the rubbery polymer (R). Approximately 0.02 g of this collected acetone-soluble component is dissolved in approximately 8 g of tetrahydrofuran (THF) to prepare a THF solution of acetone-soluble components. Using this solution, the acetone content can be determined by converting polystyrene as the standard substance from a GPC chromatogram. The GPC measurement can be performed under the following conditions. Measuring device: Waters2695 Column temperature: 40℃ Detector: RI2414 (differential refractometer) Carrier eluent flow rate: 0.3 ml / min (solvent: tetrahydrofuran) Columns: TSKgel SuperHZM-M (6.0mm I.D. × 15cm), TSKgel SuperHZM-N (6.0mm I.D. × 15cm) in series (both manufactured by Tosoh Corporation).

[0036] Furthermore, when obtaining the rubbery polymer (R) from the latex of the rubbery polymer (R), 10 ml of the latex of the rubbery polymer (R) is added to 150 ml of methanol to obtain a methanol dispersion. Then, 20 ml of a calcium chloride aqueous solution adjusted to 10% by mass is added to the methanol dispersion, and the rubbery polymer (R) can be obtained by dehydration, washing, and vacuum drying.

[0037] As a polymerization method for rubbery polymers (R), emulsion polymerization is employed from the viewpoint of adjusting the degree of crosslinking and particle size distribution of the rubbery polymer (R) to a desired range by balancing the monomer oil droplets, aqueous phase, and polymer particles.

[0038] There are no particular restrictions on the initiator used in polymerization; peroxides, azo compounds, or persulfates are commonly used.

[0039] Specific examples of peroxides include benzoyl peroxide, cumene hydroperoxide, dicumyl peroxide, diisopropylbenzene hydroperoxide, t-butyl hydroperoxide, t-butyl peroxyacetate, t-butyl peroxybenzoate, t-butyl isopropyl carbonate, di-t-butyl peroxide, t-butyl peroctoate, 1,1-bis(t-butylperoxy)3,3,5-trimethylcyclohexane, 1,1-bis(t-butylperoxy)cyclohexane, and t-butylperoxy-2-ethylhexanoate.

[0040] Specific examples of azo compounds include azobisisobutyronitrile, azobis(2,4-dimethylvaleronitrile), 2-phenylazo-2,4-dimethyl-4-methoxyvaleronitrile, 2-cyano-2-propylazoformamide, 1,1'-azobiscyclohexane-1-carbonnitrile, azobis(4-methoxy-2,4-dimethylvaleronitrile), dimethyl-2,2'-azobiisobutyrate, 1-t-butylazo-2-cyanobutane, and 2-t-butylazo-2-cyano-4-methoxy-4-methylpentane.

[0041] Specific examples of persulfates include potassium persulfate, sodium persulfate, and ammonium persulfate.

[0042] Two or more of these initiators may be used. Potassium persulfate and cumene hydroperoxide are preferred for emulsion polymerization. Redox initiators can also be used.

[0043] In the present invention, the emulsifier used in the emulsion polymerization method of the rubbery polymer (R) is a sulfosuccinate compound (E) represented by the following chemical formula [1] and disproportionated rosin (F).

[0044] The sulfosuccinate compound (E) used in the present invention is a compound represented by the following chemical formula [1].

[0045] [ka]

[0046] (R is an alkyl or alkenyl group having 8 to 22 carbon atoms, AO is an oxyalkylene group having 2 or 3 carbon atoms, n is an integer from 0 to 20, M and N are independently hydrogen, an alkali metal, or an alkaline earth metal, p is 1 if M is hydrogen or an alkali metal, and 1 / 2 if M is an alkaline earth metal, and q is 1 if N is hydrogen or an alkali metal, and 1 / 2 if N is an alkaline earth metal.) In chemical formula [1], R represents an alkyl group or alkenyl group having 8 to 22 carbon atoms. The alkyl group may be linear or branched, and may also contain a ring structure such as a cycloalkyl structure. The number of carbon atoms in the alkyl group is preferably 12 or more, and more preferably 16 or less. Specifically, R is preferably an n-dodecyl group, an n-tridecyl group, an n-tetradecyl group, or an isotridecyl group.

[0047] AO represents an oxyalkylene group having 2 or 3 carbon atoms. This oxyalkylene group may be linear or branched. Specifically, it may be an oxyethylene group or an oxypropylene group.

[0048] M and N each independently represent hydrogen, an alkali metal, or an alkaline earth metal. Examples of alkali metals include sodium, potassium, lithium, rubidium, and cesium, while examples of alkaline earth metals include calcium, barium, magnesium, and strontium. Among these, hydrogen, sodium, potassium, calcium, and magnesium are preferred for M and N, with sodium and potassium being more preferred.

[0049] n is an integer between 0 and 20, preferably an integer greater than or equal to 3, and preferably an integer less than or equal to 10.

[0050] The sulfosuccinate compound (E) represented by the chemical formula [1] is preferably, for example, mono-n-dodecylsulfosuccinate, mono-n-dodecylmonoxyethylenesulfosuccinate, mono-n-dodecyldioxyethylenesulfosuccinate, or their alkali metal salts or alkaline earth metal salts. More preferably, it is an alkali metal salt of mono-n-dodecylsulfosuccinate, mono-n-dodecylmonoxyethylenesulfosuccinate, or mono-n-dodecyldioxyethylenesulfosuccinate.

[0051] These sulfosuccinate compounds (E) may be used individually or in combination of two or more.

[0052] Products containing the sulfosuccinate compound (E) represented by the chemical formula [1] include Kohacool L-300 manufactured by Toho Chemical Industries, Ltd.

[0053] In step 1-A, the amount of sulfosuccinate compound (E) represented by the chemical formula [1] is 0.15 to 0.45 parts by mass per 100 parts by mass of monomer mixture (r) consisting of 97 to 99.5 parts by mass of alkyl acrylate monomer (r1) and 0.5 to 3 parts by mass of polyfunctional monomer (r2). If the amount of sulfosuccinate compound (E) is less than 0.15 parts by mass, large particle size rubber exceeding 1 μm, as shown in Figure 1, is produced during emulsion polymerization, resulting in a decrease in the surface smoothness and color development of the molded product. On the other hand, if the amount of sulfosuccinate compound (E) exceeds 0.45 parts by mass, the impact resistance and appearance of the molded product deteriorate.

[0054] Disproportionated rosin (F) refers to disproportionated rosinic acid obtained by adding a catalyst to rosin, which is a monobasic acid having a cyclic diterpene skeleton, and then heating and melting it to induce hydrogen transfer, or its alkali metal salts or alkaline earth metal salts. For example, natural rosins such as gum rosin, tall oil rosin, and wood rosin contain not only abietic acid as the main component, but also neoabietic acid, palastic acid, dehydroabietic acid, pimaric acid, isopimaric acid, etc. Disproportionated rosinic acid can be obtained by disproportionating these unrefined rosins. Usually, it is preferable to use this disproportionated rosinic acid as an alkali metal salt by saponifying it with potassium hydroxide or the like.

[0055] Examples of products containing disproportionated rosin (F) include Diplozine A-100 and Diplozine K-25, manufactured by Toho Chemical Industry Co., Ltd.

[0056] In step 1-A, the amount of disproportionated rosin (F) added is 1.5 to 3 parts by mass per 100 parts by mass of monomer mixture (r) consisting of 97 to 99.5 parts by mass of alkyl acrylate monomer (r1) and 0.5 to 3 parts by mass of polyfunctional monomer (r2). If the amount of disproportionated rosin (F) added is less than 1.5 parts by mass, the impact resistance of the molded product decreases and the appearance of the molded product deteriorates. On the other hand, if the amount of disproportionated rosin (F) added exceeds 3 parts by mass, the surface smoothness and color development of the molded product deteriorate.

[0057] Furthermore, in step 1-A, the mass ratio of sulfosuccinate compound (E) to disproportionated rosin (F) (sulfosuccinate compound (E): disproportionated rosin (F)) is preferably 9:91 to 30:70. More preferably, it is 9:91 to 20:80. If the sulfosuccinate compound (E) is blended in a ratio lower than 9:91, large-particle rubber exceeding 1 μm, as shown in Figure 1, may be formed during emulsion polymerization, which is undesirable because it can reduce the surface smoothness and color development of the molded product. On the other hand, if the sulfosuccinate compound (E) is blended in a ratio higher than 30:70, it is undesirable because it can reduce the impact resistance of the molded product and also reduce its appearance.

[0058] [(Step 1-B) Graft copolymerization of a monomer mixture (a) containing at least an aromatic vinyl monomer (a1) and a vinyl cyanide monomer (a2) with the rubbery polymer (R) in the presence of the latex of the rubbery polymer (R) to obtain the latex of the graft copolymer (A)].

[0059] In the present invention, graft copolymer (A) refers to the general term for polymers produced in the process of obtaining graft copolymer (A), and includes polymers produced by graft polymerization onto rubbery polymer (R), as well as polymer components produced without graft polymerization onto rubbery polymer (R).

[0060] The content of the rubbery polymer (R) in the graft copolymer (A) is preferably 20% by mass or more and 80% by mass or less relative to the total amount of the graft copolymer (A). If the content of the rubbery polymer (R) relative to the total amount of the graft copolymer (A) is 20% by mass or more, the impact resistance of the molded article can be further improved. The content of the rubbery polymer (R) relative to the total amount of the graft copolymer (A) is more preferably 35% by mass or more. On the other hand, if the content of the rubbery polymer (R) relative to the total amount of the graft copolymer (A) is 80% by mass or less, the fluidity of the final resin composition, the impact resistance of the molded article, the surface smoothness, the color development, and the appearance of the molded article can be further improved. The content of the rubbery polymer (R) relative to the total amount of the graft copolymer (A) is more preferably 60% by mass or less.

[0061] Examples of aromatic vinyl monomers (a1) in monomer mixture (a) include styrene, α-methylstyrene, p-methylstyrene, m-methylstyrene, o-methylstyrene, vinyltoluene, and t-butylstyrene. Two or more of these may be used as aromatic vinyl monomers (a1). Among aromatic vinyl monomers (a1), styrene is preferred from the viewpoint of further improving the fluidity of the final resin composition and the rigidity of the molded article.

[0062] From the viewpoint of further improving the fluidity of the final resin composition and the rigidity of the molded article, the content of aromatic vinyl monomer (a1) in monomer mixture (a) is preferably 60% by mass or more, more preferably 65% ​​by mass or more, and even more preferably 70% by mass or more, based on 100% by mass of the total monomer mixture (a). On the other hand, from the viewpoint of improving the impact resistance of the molded article, the content of aromatic vinyl monomer (a1) in monomer mixture (a) is preferably 85% by mass or less, more preferably 80% by mass or less, and even more preferably 75% by mass or less.

[0063] Examples of vinyl cyanide monomers (a2) in monomer mixture (a) include acrylonitrile, methacrylonitrile, and ethacrylonitrile. Two or more of these may be included as vinyl cyanide monomers (a2). Among vinyl cyanide monomers (a2), acrylonitrile is preferred from the viewpoint of further improving the impact resistance of the molded product.

[0064] From the viewpoint of improving the impact resistance of the molded product, the content of vinyl cyanide monomer (a2) in monomer mixture (a) is preferably 20% by mass or more, more preferably 25% by mass or more, and even more preferably 30% by mass or more, based on 100% by mass of the total of monomer mixture (a). On the other hand, from the viewpoint of improving the fluidity of the final resin composition and the color tone of the molded product, the content of vinyl cyanide monomer (a2) in monomer mixture (a) is preferably 40% by mass or less, and more preferably 35% by mass or less.

[0065] The monomer mixture (a) may further contain other monomers copolymerizable with the aromatic vinyl monomer (a1) and the vinyl cyanide monomer (a2).

[0066] Other monomers copolymerizable with the aforementioned aromatic vinyl monomer (a1) and vinyl cyanide monomer (a2) are vinyl monomers other than the aforementioned aromatic vinyl monomer (a1) and vinyl cyanide monomer (a2), and are not particularly limited as long as they do not impair the effects of the present invention. Specific examples of other monomers include (meth)acrylic acid ester monomers (a3), unsaturated fatty acids, acrylamide monomers, maleimide monomers, and two or more of these may be used.

[0067] As the (meth)acrylic acid ester monomer (a3) ​​that may be included in the monomer mixture (a), for example, an ester of an alcohol having 1 to 6 carbon atoms with acrylic acid or methacrylic acid is preferred. The ester of an alcohol having 1 to 6 carbon atoms with acrylic acid or methacrylic acid may further have substituents such as hydroxyl groups or halogen groups. Examples of esters of an alcohol having 1 to 6 carbon atoms with acrylic acid or methacrylic acid include methyl (meth)acrylate, ethyl (meth)acrylate, n-propyl (meth)acrylate, n-butyl (meth)acrylate, t-butyl (meth)acrylate, n-hexyl (meth)acrylate, cyclohexyl (meth)acrylate, chloromethyl (meth)acrylate, 3-hydroxypropyl (meth)acrylate, 2,3,4,5,6-pentahydroxyhexyl (meth)acrylate, and 2,3,4,5-tetrahydroxypentyl (meth)acrylate. Two or more of these may be included as (meth)acrylic acid ester monomers (a3). Among the (meth)acrylic acid ester monomers (a3), methyl (meth)acrylate is preferred from the viewpoint of further improving the color development of the molded product. In this specification, "(meth)acrylic acid" means both acrylic acid and methacrylic acid, and for example, methyl (meth)acrylate has the meaning of both methyl methacrylate and methyl acrylate.

[0068] When using a (meth)acrylic acid ester monomer (a3), the content of (meth)acrylic acid ester monomer (a3) ​​in the monomer mixture (a) is preferably 30% by mass or more, more preferably 50% by mass or more, and even more preferably 70% by mass or more, based on 100% by mass of the total of the monomer mixture (a), from the viewpoint of further improving the color development of the molded product. On the other hand, the content of (meth)acrylic acid ester monomer (a3) ​​in the monomer mixture (a) is preferably 90% by mass or less, more preferably 85% by mass or less, and even more preferably 80% by mass or less, from the viewpoint of further improving the impact resistance of the molded product.

[0069] Examples of unsaturated fatty acids include itaconic acid, maleic acid, fumaric acid, butenic acid, acrylic acid, and methacrylic acid. Examples of acrylamide monomers include acrylamide, methacrylamide, and N-methylacrylamide. Examples of maleimide monomers include N-methylmaleimide, N-ethylmaleimide, N-isopropylmaleimide, N-butylmaleimide, N-hexylmaleimide, N-octylmaleimide, N-dodecylmaleimide, N-cyclohexylmaleimide, and N-phenylmaleimide.

[0070] The weight-average molecular weight of the acetonitrile-soluble portion of the graft copolymer (A) is not particularly limited, but is preferably 50,000 or more, and more preferably 60,000 or more. If the weight-average molecular weight of the acetonitrile-soluble portion of the graft copolymer (A) is 50,000 or more, the impact resistance of the molded article can be further improved. On the other hand, the weight-average molecular weight of the acetonitrile-soluble portion of the graft copolymer (A) is preferably 120,000 or less, and more preferably 100,000 or less. If the weight-average molecular weight of the acetonitrile-soluble portion of the graft copolymer (A) is 120,000 or less, the fluidity of the final resin composition can be further improved.

[0071] Here, the weight-average molecular weight of the acetonitrile-soluble portion of graft copolymer (A) is prepared by concentrating the filtrate obtained by filtering the acetonitrile-insoluble portion from graft copolymer (A) using a rotary evaporator. Approximately 0.03 g of the acetonitrile-soluble portion is then dissolved in approximately 15 g of tetrahydrofuran to prepare a solution of approximately 0.2% by mass. The GPC chromatogram measured using this solution can be determined by converting it to a standard substance using polystyrene. (However, if a (meth)acrylic acid ester monomer (a3) ​​is used in monomer mixture (a), polymethyl methacrylate is used as the standard substance.) The GPC measurement can be performed under the following conditions. Measuring device: Waters2695 Column temperature: 40℃ Detector: RI2414 (differential refractometer) Carrier eluent flow rate: 0.3 ml / min (solvent: tetrahydrofuran) Columns: TSKgel SuperHZM-M (6.0mm I.D. × 15cm), TSKgel SuperHZM-N (6.0mm I.D. × 15cm) in series (both manufactured by Tosoh Corporation).

[0072] There are no particular restrictions on the grafting ratio of the graft copolymer (A), but from the viewpoint of improving the impact resistance, surface smoothness, and color development of the molded product, it is preferable to have a ratio of 10% to 100%. More preferably, it is 30% to 60%.

[0073] Here, the grafting rate of graft copolymer (A) can be determined by the following method. First, 80 ml of acetonitrile is added to approximately 1 g of graft copolymer (A), and refluxed in a 70°C water bath for 3 hours. This solution is centrifuged at 8000 r.pm (10000 G) for 40 minutes, and the insoluble matter is filtered to obtain acetonitrile-insoluble matter. The obtained acetonitrile-insoluble matter is dried under reduced pressure at 80°C for 5 hours, and its mass (n (unit: "g") in the following formula) is measured, and the grafting rate is calculated from the following formula. Here, m is the sample mass of graft copolymer (A) used (unit: "g"), and X is the content (mass%) of rubbery polymer (R) in graft copolymer (A). Graft rate (%) = {[(n)-((m)×X / 100)] / [(m)×X / 100]}×100.

[0074] In step 1-B, when graft copolymerizing the monomer mixture (a) onto the latex of the rubbery polymer (R), emulsion polymerization is preferred because it allows for easy temperature control during polymerization.

[0075] In step 1-B, the following anionic surfactants can be used as emulsifiers during graft copolymerization. An anionic surfactant, as used here, is a surfactant having an anionic hydrophilic group. Examples of anionic surfactants include carboxylic acid type, sulfate ester type, sulfonic acid type, sulfosuccinate type, and phosphate ester salt type, and two or more of these may be used. However, some of the above emulsifiers do not coagulate easily when in contact with acid in step 1-C, which will be described later, and these emulsifiers should be used within the range in which they can coagulate with acid. In particular, in step 1-C, carboxylic acid type and sulfosuccinate type anionic surfactants are more preferably used due to their ease of coagulation when in contact with acid, and carboxylic acid type anionic surfactants are even more preferably used.

[0076] Examples of carboxylic acid-type anionic surfactants include fatty acid compounds (G) and disproportionated rosin (F). Among carboxylic acid-type anionic surfactants, fatty acid compounds (G) are most preferred from the viewpoint of the color tone of the molded product.

[0077] In this context, fatty acid compounds (G) refer to monovalent carboxylic acids having a carboxylic acid group in their hydrocarbon chain, or their alkali metal salts or alkaline earth metal salts. Examples include caprylic acid, capric acid, lauric acid, myristic acid, myristoleic acid, palmitic acid, palmitoleic acid, margaric acid, stearic acid, oleic acid, linoleic acid, linolenic acid, behenic acid, arachidic acid, pentadecylic acid, or their alkali metal salts or alkaline earth metal salts.

[0078] Examples of sulfate ester-type anionic surfactants include castor oil sulfate, lauryl alcohol sulfate, polyoxyethylene lauryl sulfate, polyoxyethylene alkyl ether sulfate, polyoxyethylene alkylphenyl ether sulfate, or their alkali metal salts or alkaline earth metal salts.

[0079] Examples of sulfonic acid-type anionic surfactants include dodecylbenzenesulfonic acid, alkylnaphthalenesulfonic acid, alkyldiphenyl ether disulfonic acid, naphthalenesulfonic acid condensates, or their alkali metal salts or alkaline earth metal salts.

[0080] When using a fatty acid compound (G) as an emulsifier during graft copolymerization, examples of products containing fatty acid compound (G) include 45° hydrogenated beef tallow (HFA) manufactured by NOF Corporation, and it is preferable to use it as an alkali metal salt after saponification with potassium hydroxide or the like.

[0081] In step 1-B, using an anionic surfactant can improve the emulsification stability of the latex of the graft copolymer (A) during graft copolymerization.

[0082] In step 1-B, when a fatty acid compound (G) is used as an emulsifier during graft copolymerization, the amount of fatty acid compound (G) is preferably 1 to 5 parts by mass, and more preferably 1 to 3 parts by mass, per 100 parts by mass of the rubbery polymer (R) and monomer mixture (a). If the amount of fatty acid compound (G) is less than 1 part by mass per 100 parts by mass of the rubbery polymer (R) and monomer mixture (a), the emulsion stability during graft copolymerization may decrease, which is undesirable. On the other hand, if the amount of fatty acid compound (G) exceeds 5 parts by mass per 100 parts by mass of the rubbery polymer (R) and monomer mixture (a), the color tone and appearance of the molded product may be inferior, which is undesirable.

[0083] Examples of polymerization initiators used in this graft copolymerization include those exemplified as initiators used in the polymerization of rubbery polymers (R).

[0084] A chain transfer agent may be used to adjust the weight-average molecular weight and graft rate of the acetonitrile-soluble component of the graft copolymer (A). Specific examples of chain transfer agents include mercaptans such as n-octyl mercaptan, t-dodecyl mercaptan, n-tetradecyl mercaptan, and n-octadecyl mercaptan, and terpenes such as terpinolene. Two or more of these may be used. Among these, n-octyl mercaptan and t-dodecyl mercaptan are preferred.

[0085] From the viewpoint of adjusting the weight-average molecular weight and graft rate of the acetonitrile-soluble portion of the graft copolymer (A) to the aforementioned preferred range, it is preferable to use 0.05 to 0.5 parts by mass of a chain transfer agent and 0.1 to 0.5 parts by mass of an initiator per 100 parts by mass of the total of the rubbery polymer (R) and monomer mixture (a) during graft copolymerization.

[0086] [(Step 1-C) The latex of the graft copolymer (A) is brought into contact with an acid, then neutralized with an alkali, washed with water, and dehydrated to obtain the graft copolymer (A)].

[0087] In step 1-C, the latex of the graft copolymer (A) obtained in step 1-B is brought into contact with an acid. This acid acts as a coagulant. Examples of acids that can be used as a coagulant include sulfuric acid, hydrochloric acid, phosphoric acid, and acetic acid. Two or more of these may be combined.

[0088] Furthermore, in order to remove excess emulsifier, the graft copolymer (A) is obtained by neutralizing with alkali, washing with water, and dehydrating after contact with acid. Sodium hydroxide is an example of an alkali that can improve the appearance of the molded product by performing such a treatment.

[0089] Specifically, a preferred embodiment involves heating an aqueous solution of acid, adjusted so that the concentration of graft copolymer (A) after the addition of latex is approximately 0.2 to 2% by mass, to approximately 50 to 95°C, gradually adding the graft copolymer (A) latex to the aqueous solution so that the concentration of graft copolymer (A) in the aqueous solution is 8 to 15% by mass, thereby bringing it into contact with the acid, and then neutralizing with alkali, washing with water, and dehydrating to obtain graft copolymer (A).

[0090] In this invention, by obtaining a latex of a rubbery polymer (R) using a specific ratio of sulfosuccinate compound (E) and disproportionated rosin (F) as described in step 1-A, the total amount of anionic surfactant in the final resin composition can be reduced to 5000 ppm (mass / mass) or less of the total amount of the resin composition, and the combined amount of sulfosuccinate compound (E) and disproportionated rosin (F) represented by the chemical formula [1] in the resin composition can be reduced to 2000 ppm (mass / mass) or less of the total amount of the resin composition through the normal water washing operation described above. As a result, it has been found that a resin composition with good impact resistance, surface smoothness, color development, and molded product appearance can be obtained, although it goes without saying that water washing should be performed to the extent necessary. Note that if the latex of the rubbery polymer (R) is not obtained using a specific ratio of sulfosuccinate compound (E) and disproportionated rosin (F), the amount of emulsifier in the resin composition will be excessive.

[0091] The amount of sulfosuccinate compound (E) contained in the graft copolymer (A) is preferably 0.015 to 0.035% by mass per 100% by mass of the graft copolymer (A). If this amount is less than 0.015% by mass, the surface smoothness and color development of the molded product may decrease, which is undesirable. On the other hand, if the amount of sulfosuccinate compound (E) contained in the graft copolymer (A) exceeds 0.035% by mass, the impact resistance and appearance of the molded product may decrease, which is undesirable.

[0092] The amount of disproportionated rosin (F) contained in the graft copolymer (A) is preferably 0.09 to 0.2% by mass relative to 100% by mass of the graft copolymer (A). If the amount of disproportionated rosin (F) contained in the graft copolymer (A) is less than 0.09% by mass, the impact resistance of the molded product may decrease, which is undesirable. On the other hand, if the amount of disproportionated rosin (F) contained in the graft copolymer (A) exceeds 0.2% by mass, the surface smoothness, color development, and appearance of the molded product may decrease, which is undesirable.

[0093] The ratio of sulfosuccinate compound (E) to disproportionated rosin (F) in the graft copolymer (A) is preferably 10:90 to 30:70 by mass ratio (sulfosuccinate compound (E): disproportionated rosin (F)). If the ratio of sulfosuccinate compound (E) to disproportionated rosin (F) in the graft copolymer (A) is 10:90 to 30:70 by mass ratio, the ratio of sulfosuccinate (E) to disproportionated rosin (F) in the resin composition described later can be easily adjusted to a mass ratio of 10:90 to 30:70.

[0094] The vinyl copolymer (B) (component 2) used in the present invention can be manufactured by step 2 described later.

[0095] [(Step 2) A monomer mixture (b) comprising at least an aromatic vinyl monomer (b1) and a vinyl cyanide monomer (b2) is copolymerized to obtain a vinyl copolymer (B)].

[0096] The vinyl copolymer (B) used in the resin composition of the present invention is obtained by copolymerizing a monomer mixture (b) containing at least an aromatic vinyl monomer (b1) and a vinyl cyanide monomer (b2). The monomer mixture (b) may further contain other monomers copolymerizable with the aromatic vinyl monomer (b1) and the vinyl cyanide monomer (b2). However, the monomer mixture (b) does not contain maleimide monomers.

[0097] Examples of aromatic vinyl monomers (b1) in monomer mixture (b) include those exemplified as aromatic vinyl monomer (a1), with styrene being preferred.

[0098] From the viewpoint of further improving the fluidity of the final resin composition and the rigidity of the molded article, the content of aromatic vinyl monomer (b1) in monomer mixture (b) is preferably 60% by mass or more, more preferably 65% ​​by mass or more, and even more preferably 70% by mass or more, based on 100% by mass of the total monomer mixture (b). On the other hand, from the viewpoint of improving the impact resistance of the molded article, the content of aromatic vinyl monomer (b1) in monomer mixture (b) is preferably 85% by mass or less, more preferably 80% by mass or less, and even more preferably 75% by mass or less, based on 100% by mass of the total monomer mixture (b).

[0099] Examples of the vinyl cyanide monomer (b2) in the monomer mixture (b) include those exemplified as vinyl cyanide monomer (a2), with acrylonitrile being preferred.

[0100] From the viewpoint of improving the impact resistance of the molded article, the content of vinyl cyanide monomer (b2) in monomer mixture (b) is preferably 20% by mass or more, more preferably 25% by mass or more, and even more preferably 30% by mass or more, based on 100% by mass of the total monomer mixture (b). On the other hand, from the viewpoint of improving the fluidity of the final resin composition and the color tone of the molded article, the content of vinyl cyanide monomer (b2) in monomer mixture (b) is preferably 40% by mass or less, and more preferably 35% by mass or less, based on 100% by mass of the total monomer mixture (b).

[0101] Furthermore, other monomers copolymerizable with the aforementioned aromatic vinyl monomer (b1) and vinyl cyanide monomer (b2) are vinyl monomers other than the aforementioned aromatic vinyl monomer (b1) and vinyl cyanide monomer (b2), and are not particularly limited as long as they do not impair the effects of the present invention.Specific examples of other monomers include (meth)acrylic acid ester monomers (b3), unsaturated fatty acids, and acrylamide monomers, and two or more of these may be used.Examples of (meth)acrylic acid ester monomers (b3) are the same as those described for (meth)acrylic acid ester monomer (a3) ​​above, examples of unsaturated fatty acids include itaconic acid, maleic acid, fumaric acid, butenoic acid, acrylic acid, and methacrylic acid, and examples of acrylamide monomers include acrylamide, methacrylamide, and N-methylacrylamide.

[0102] The weight-average molecular weight of vinyl copolymer (B) is preferably 70,000 or more, and more preferably 80,000 or more. By setting the weight-average molecular weight of vinyl copolymer (B) to 70,000 or more, the impact resistance of the molded product can be further improved. On the other hand, the weight-average molecular weight of vinyl copolymer (B) is preferably 200,000 or less, and more preferably 150,000 or less. By setting the weight-average molecular weight of vinyl copolymer (B) to 200,000 or less, the fluidity of the final resin composition can be further improved. Vinyl copolymer (B) with a weight-average molecular weight in the range of 70,000 to 200,000 can be easily produced, for example, by using initiators and chain transfer agents described later, or by setting the polymerization temperature to the preferred range described later.

[0103] Here, the weight-average molecular weight of vinyl copolymer (B) can be determined by converting the GPC chromatogram obtained by dissolving approximately 0.03 g of vinyl copolymer (B) in approximately 15 g of tetrahydrofuran to a solution of approximately 0.2% by mass, using polystyrene as the standard substance. (However, when using (meth)acrylic acid ester monomer (b3) in monomer mixture (b), polymethyl methacrylate is used as the standard substance.) The GPC measurement can be performed under the following conditions. Measuring device: Waters2695 Column temperature: 40℃ Detector: RI2414 (differential refractometer) Carrier eluent flow rate: 0.3 ml / min (solvent: tetrahydrofuran) Columns: TSKgel SuperHZM-M (6.0mm I.D. × 15cm), TSKgel SuperHZM-N (6.0mm I.D. × 15cm) in series (both manufactured by Tosoh Corporation).

[0104] There are no particular restrictions on the method for producing the vinyl copolymer (B), but from the viewpoint of moldability of the final resin composition and the color tone of the molded product, continuous bulk polymerization or continuous solution polymerization is preferably used. Here, continuous bulk polymerization is a method in which monomer mixture (b) is continuously added over time and the bulk polymerized vinyl copolymer (B) is continuously discharged over time, and continuous solution polymerization is a method in which monomer mixture (b) and solvent are continuously added over time and the solution consisting of the solution polymerized vinyl copolymer (B) and solvent is continuously discharged over time.

[0105] Any method can be used to produce the vinyl copolymer (B) by continuous bulk polymerization or continuous solution polymerization. For example, one method is to polymerize a monomer mixture (b) in a polymerization tank and then remove the monomer (de-monomerize and de-volatilize).

[0106] For polymerization tanks, for example, mixing-type polymerization tanks with stirring blades such as paddle blades, turbine blades, propeller blades, bull margin blades, multi-stage blades, anchor blades, Maxblend blades, and double helical blades, as well as various types of tower reactors, can be used. In addition, multi-tube reactors, kneader reactors, and twin-screw extruders can also be used as polymerization reactors (see, for example, Polymer Manufacturing Process Assessment 10 "Assessment of Impact-Resistant Polystyrene," The Society of Polymer Science, Japan, published January 26, 1989).

[0107] When producing the vinyl copolymer (B), two or more of the above-mentioned polymerization tanks or polymerization reactors may be used, or two or more types of polymerization tanks or polymerization reactors may be combined as needed. From the viewpoint of reducing the molecular weight distribution of the vinyl copolymer (B), it is preferable to use two or fewer polymerization tanks or polymerization reactors, and a single-tank, fully mixed polymerization tank is more preferable.

[0108] The reaction mixture obtained by polymerization in the polymerization tank or polymerization reactor described above is usually subjected to a demonomerization step to remove monomers, solvents, and other volatile components. Methods for demonomerization include, for example, removing volatile components through vent holes under heating at atmospheric or reduced pressure using a single-screw or twin-screw extruder with vents; removing volatile components using an evaporator with a plate-fin type heater, such as a centrifugal type, built into the drum; removing volatile components using a thin-film evaporator, such as a centrifugal type; and removing volatile components by preheating, foaming, and flushing into a vacuum chamber using a multi-tube heat exchanger. Among these methods for demonomerization, the method of removing volatile components using a single-screw or twin-screw extruder with vents is particularly preferred.

[0109] When producing vinyl copolymer (B), initiators and chain transfer agents may be used as appropriate. Examples of initiators and chain transfer agents include the same initiators and chain transfer agents exemplified in the method for producing graft copolymer (A).

[0110] There are no particular restrictions on the amount of initiator added to produce the vinyl copolymer (B), but from the viewpoint of easily adjusting the weight-average molecular weight of the vinyl copolymer (B) to the aforementioned range, it is preferable to add 0.01 parts by mass or more and 0.03 parts by mass or less per 100 parts by mass of the total monomer mixture (b).

[0111] There are no particular restrictions on the amount of chain transfer agent used to produce the vinyl copolymer (B), but from the viewpoint of easily adjusting the weight-average molecular weight of the vinyl copolymer (B) to the aforementioned range, it is preferable to add 0.05 parts by mass or more and 0.40 parts by mass or less per 100 parts by mass of the total monomer mixture (b).

[0112] When producing vinyl copolymer (B) by continuous bulk polymerization or continuous solution polymerization, there are no particular restrictions on the polymerization temperature, but from the viewpoint of easily adjusting the weight-average molecular weight of vinyl copolymer (B) to the aforementioned range, a temperature of 120°C to 140°C is preferred.

[0113] When producing vinyl copolymer (B) by continuous solution polymerization, the amount of solvent is preferably 30% by mass or less, and more preferably 20% by mass or less, in the polymerization solution from the viewpoint of productivity. From the viewpoint of polymerization stability, ethylbenzene or methyl ethyl ketone is preferred as the solvent, and ethylbenzene is particularly preferred.

[0114] The heat-resistant vinyl copolymer (C) used in the present invention can be produced by step 4 described later.

[0115] [(Step 4) A monomer mixture (c) containing at least an aromatic vinyl monomer (c1) and a maleimide monomer (c2) is copolymerized to obtain a heat-resistant vinyl copolymer (C)].

[0116] The resin composition of the present invention may optionally contain a heat-resistant vinyl copolymer (C) obtained by copolymerizing a monomer mixture (c) containing at least an aromatic vinyl monomer (c1) and a maleimide monomer (c2). The inclusion of the heat-resistant vinyl copolymer (C) imparts heat resistance to the final resin composition.

[0117] Examples of aromatic vinyl monomers (c1) in monomer mixture (c) include those exemplified as aromatic vinyl monomer (a1), with styrene being preferred.

[0118] Examples of maleimide monomers (c2) in monomer mixture (c) include N-methylmaleimide, N-isopropylmaleimide, N-butylmaleimide, N-hexylmaleimide, N-octylmaleimide, N-dodecylmaleimide, N-cyclohexylmaleimide, N-phenylmaleimide, and the corresponding maleic acid or maleic anhydride. (Note that when maleic acid or maleic anhydride is used, imidization with an amine compound is performed before or after copolymerization of monomer mixture (c)). Two or more of these may be included as maleimide monomers (c2). Among the maleimide monomers (c2), N-phenylmaleimide is preferred from the viewpoint of improving the heat resistance of the final resin composition.

[0119] Furthermore, within the limits that do not hinder the objectives of the present invention, monomers other than the aforementioned aromatic vinyl monomer (c1) and maleimide monomer (c2) may be included in the monomer mixture (c). Specific examples of such other monomers include vinyl cyanide monomer (c3), unsaturated fatty acids, and acrylamide monomers, and two or more of these may be included.

[0120] Examples of the vinyl cyanide monomer (c3) in the monomer mixture (c) include those exemplified as vinyl cyanide monomer (a2), with acrylonitrile being preferred.

[0121] In the monomer mixture (c) used in the heat-resistant vinyl copolymer (C), there are no particular restrictions on the composition ratio of each monomer. However, when the total amount of the monomer mixture (c) is 100% by mass, it is preferable that the aromatic vinyl monomer (c1) is 36-65% by mass, the maleimide monomer (c2) is 35-52% by mass, preferably 37-50% by mass, and the cyanide vinyl monomer (c3) is 0-12% by mass. In particular, if the content of the maleimide monomer (c2) is less than 35% by mass, the effect of improving the heat resistance of the final resin composition is small, while if it exceeds 52% by mass, the moldability of the final resin composition may be impaired.

[0122] The reduced viscosity of a 0.4 g / dl dimethyl sulfoxide solution of the heat-resistant vinyl copolymer (C), measured with an Ubbelohde viscometer at 30°C, is preferably 0.3 to 0.7 dl / g, and more preferably 0.4 to 0.6 dl / g. If the reduced viscosity of the heat-resistant vinyl copolymer (C) is less than 0.3 dl / g, the impact resistance of the molded product may decrease. On the other hand, if it exceeds 0.7 dl / g, the fluidity of the final resin composition may decrease, resulting in reduced moldability.

[0123] The final resin composition of the present invention can be produced by step 3, which is described later. In step 3, a sulfosuccinate compound (E) (component 3) and disproportionated rosin (F) (component 4) are added to the final resin composition.

[0124] [(Step 3) A step of mixing the graft copolymer (A) obtained in Steps 1 and 2, the vinyl copolymer (B), and the heat-resistant vinyl copolymer (C) obtained in Step 4 (where the heat-resistant vinyl copolymer (C) is an optional component)].

[0125] In the process of mixing the graft copolymer (A), vinyl copolymer (B), and heat-resistant vinyl copolymer (C) (where heat-resistant vinyl copolymer (C) is an optional component), there are no particular restrictions on the melt-kneading method, but methods such as melt-kneading using a single-screw or twin-screw cylinder with a heating device and vents can be employed. The heating temperature during melt-kneading is usually selected from the range of 210 to 320°C, but it is also possible to freely set the temperature gradient during melt-kneading as long as it does not impair the objective of the present invention. Furthermore, when using twin-screw cylinders, they may be rotated in the same direction or in different directions.

[0126] The resin composition of the present invention is preferably formed by blending 10 to 60 parts by mass of graft copolymer (A) and 40 to 90 parts by mass of vinyl copolymer (B) with a total of 100 parts by mass of graft copolymer (A) and vinyl copolymer (B). Having 10 parts by mass or more of graft copolymer (A) and 90 parts by mass or less of vinyl copolymer (B) suppresses a decrease in the impact resistance of the molded article. More preferably, with a total of 100 parts by mass of graft copolymer (A) and vinyl copolymer (B), the amount of graft copolymer (A) is 20 parts by mass or more and vinyl copolymer (B) is 80 parts by mass or less. Furthermore, by having 60 parts by mass or less of graft copolymer (A) and 40 parts by mass or more of vinyl copolymer (B), it is possible to suppress an increase in the melt viscosity of the final resin composition while suppressing a decrease in fluidity, and also suppress a decrease in the surface smoothness, color development, and appearance of the molded article. It is more preferable to blend 50 parts by mass or less of graft copolymer (A) and 50 parts by mass or more of vinyl copolymer (B) with a total of 100 parts by mass of graft copolymer (A) and vinyl copolymer (B). Note that two or more types of graft copolymer (A) may be blended, for example, by using graft copolymers (A) made from different rubbery polymers (R). Similarly, two or more types of vinyl copolymer (B) may be blended.

[0127] The content of the rubbery polymer (R) contained in the resin composition of the present invention is preferably 10 to 35% by mass, more preferably 15 to 30% by mass, and even more preferably 15 to 25% by mass, based on 100% by mass of the total amount of all resin components. If the content of the rubbery polymer (R) is 10% by mass or more based on 100% by mass of the total amount of all resin components, the impact resistance of the molded product can be further improved. On the other hand, if the content of the rubbery polymer (R) is 35% by mass or less based on 100% by mass of the total amount of all resin components, the fluidity of the final resin composition, the surface smoothness of the molded product, the color development, and the appearance of the molded product can be further improved.

[0128] When the resin composition of the present invention contains a heat-resistant vinyl copolymer (C), its content is preferably 10 to 38% by mass, more preferably 12 to 36% by mass, and even more preferably 15 to 35% by mass, based on 100% by mass of the total amount of all resin components. By setting the content within this range, the effect of improving the heat resistance of the molded product is further enhanced, and the impact resistance of the molded product and the fluidity of the final resin composition are also more significantly improved.

[0129] The resin composition of the present invention has a ratio of 5000 ppm (mass / mass) or less of the total amount of anionic surfactant to the total amount of the entire resin composition. A ratio of 3500 ppm (mass / mass) or less is more preferable. An anionic surfactant is a surfactant in which the hydrophilic portion becomes a negative ion in water. If the ratio of the total amount of anionic surfactant to the total amount of the entire resin composition exceeds 5000 ppm (mass / mass), the appearance of the molded product deteriorates significantly.

[0130] The resin composition of the present invention has a ratio of 2000 ppm (mass / mass) or less of the total amount of sulfosuccinate compound (E) and disproportionated rosin (F) relative to the total amount of the entire resin composition. A ratio of 1500 ppm (mass / mass) or less is more preferable. If the ratio of 2000 ppm (mass / mass) or less of the total amount of sulfosuccinate compound (E) and disproportionated rosin (F) relative to the total amount of the entire resin composition exceeds 2000 ppm (mass / mass), the appearance of the molded article deteriorates significantly.

[0131] The resin composition of the present invention has a mass ratio of sulfosuccinate compound (E) to disproportionated rosin (F) of 10:90 to 30:70 (sulfosuccinate compound (E): disproportionated rosin (F)). More preferably, the mass ratio is 10:90 to 20:80. If the sulfosuccinate compound (E) is contained in a mass ratio below 10:90 relative to 100% by mass of the total content of sulfosuccinate compound (E) and disproportionated rosin (F), the surface smoothness and color development of the molded article will decrease. On the other hand, if the sulfosuccinate compound (E) is contained in a mass ratio exceeding 30:70 relative to 100% by mass of the total content of sulfosuccinate compound (E) and disproportionated rosin (F), the impact resistance of the molded article will decrease, and the appearance of the molded article will also deteriorate.

[0132] The resin composition of the present invention may contain, to the extent that it does not impair the objectives of the present invention, inorganic fillers such as glass fibers, glass powder, glass beads, glass flakes, alumina, alumina fibers, carbon fibers, graphite fibers, stainless steel fibers, whiskers, potassium titanate fibers, warlastenite, asbestos, hard clay, calcined clay, talc, kaolin, mica, calcium carbonate, magnesium carbonate, aluminum oxide, and minerals; impact modifiers such as silicone compounds; antioxidants such as hindered phenols, sulfur-containing compounds, or phosphorus-containing organic compounds; heat stabilizers such as phenols and acrylates; and benzotriazoles, benzof It may contain ultraviolet absorbers such as phenone-based or salicylate-based; hindered amine-based light stabilizers; lubricants and plasticizers such as higher fatty acids, acid esters, acid amides, or higher alcohols; release agents such as montanic acid and its salts, its esters, its half-esters, stearyl alcohol, stearamide, and ethylene wax; various flame retardants; flame retardant aids; color inhibitors such as phosphates and hypophosphates; neutralizing agents such as phosphoric acid, monosodium phosphate, maleic anhydride, and succinic anhydride; nucleating agents; antistatic agents such as amine-based, sulfonic acid-based, and polyether-based agents; colorants such as carbon black, pigments, and dyes, and bluing agents.

[0133] The resin composition of the present invention can be molded into a molded product by any molding method. Examples of molding methods include injection molding, extrusion molding, inflation molding, blow molding, vacuum molding, compression molding, and gas-assisted molding, with injection molding being preferred. The cylinder temperature during injection molding is preferably 210°C to 320°C, and the mold temperature is preferably 30°C to 80°C.

[0134] The resin composition of the present invention can be widely used as molded articles of any shape. Examples of molded articles include films, sheets, fibers, cloths, nonwoven fabrics, injection molded articles, extruded articles, vacuum pressure molded articles, blow molded articles, and composites with other materials.

[0135] The resin composition of the present invention is useful for applications such as home appliances, communication equipment, general merchandise, and automotive materials because it can produce a resin composition with good impact resistance, surface smoothness, color development, and molded product appearance. The heat-resistant vinyl copolymer-containing resin composition, which has been given heat resistance, possesses both fluidity and impact resistance suitable for large molded products, and has an excellent molded product appearance. Therefore, it can be particularly suitably used for automotive exterior parts such as rear spoilers, wheel caps, door mirrors, radiator grilles, and lamp housings, as well as automotive interior parts such as power window panels, center consoles, center clusters, lever controllers, and console boxes. [Examples]

[0136] The present invention will be described in more detail below with reference to examples, but the present invention is not limited to these examples. First, the evaluation method will be explained.

[0137] (1) Volume average particle size of rubbery polymer (R) The latex of the rubbery polymer (R) was diluted and dispersed in an aqueous medium, and the particle size distribution was measured using a laser scattering diffraction particle size distribution analyzer "LS 13 320XR" (Beckman Coulter, Inc.). From this particle size distribution, the volume-average particle size of the rubbery polymer (R) was calculated.

[0138] (2) Grafting rate of graft copolymer (A) Approximately 1 g of graft copolymer (A) was mixed with 80 ml of acetonitrile and refluxed in a 70°C water bath for 3 hours. This solution was centrifuged at 8000 r.pm (10000 G) for 40 minutes, and the insoluble matter was filtered to obtain acetonitrile-insoluble matter. The obtained acetonitrile-insoluble matter was dried under reduced pressure at 80°C for 5 hours, and its mass (n (unit: "g") in the following formula) was measured. The graft rate was then calculated using the following formula. Here, m is the sample mass of graft copolymer (A) used (unit: "g"), and X is the rubbery polymer content (mass%) of graft copolymer (A). Graft rate (%) = {[(n)-((m)×X / 100)] / [(m)×X / 100]}×100.

[0139] (3) Content of sulfosuccinate compounds (E), disproportionate rosin (F), and other anionic surfactants (such as fatty acid compounds (G)) in the resin composition 0.1 g of the resin composition was mixed with 10 ml of chloroform and allowed to stand for 12 hours. After sonication for 1 hour, 0.1 mL of the prepared solution was taken into a microtest tube. 0.9 mL of methanol containing 1 vol% formic acid was added to the prepared solution to dilute it 10-fold, and the mixture was vigorously stirred. Then, centrifugation (15,000 G) was performed for 15 minutes, and the supernatant was prepared as the sample solution.

[0140] LC / MS analysis was performed under the following conditions. The top two most abundant target molecules were selected as monitor ions, and the content of sulfosuccinate compounds (E), disproportionated rosin (F), and other anionic surfactants (such as fatty acid compounds (G)) in the resin composition was measured relative to each monitor ion using calibration curves of standard solutions of each surfactant prepared in advance. The higher value was adopted from the content calculated from each of the two monitor ions for sulfosuccinate compounds (E), disproportionated rosin (F), and other anionic surfactants (such as fatty acid compounds (G)) in the resin composition. Measurement conditions for sulfosuccinate compounds (E): HPLC: LC-20A [Shimadzu Corporation] Mass spectrometer: API5000 [manufactured by SCIEX] Column: ODS-type column Mobile phase: A. 10 mmol / L ammonium acetate aqueous solution B. Acetonitrile Gradient conditions Injection volume: 3μL Ionization: APCI Detection: Negative ion detection Measurement mode: SRM (Selected reaction monitoring) Monitor ions: n-dodecyl sulfosuccinate * (Q1 m / z 365.2, Q3 m / z 81.0) Monopolyoxyethylene-n-dodecyl sulfosuccinate * (Q1 m / z 409.2, Q3 m / z 81.0) *[MH] - Set to monitor ions. Measurement conditions for disproportionated rosin (F): HPLC: LC-20A [Shimadzu Corporation] Mass spectrometer: API5000 [manufactured by SCIEX] Column: ODS-type column Mobile phase: A. 10 mmol / L ammonium acetate aqueous solution B. Acetonitrile Gradient conditions Injection volume: 3μL Ionization: APCI Detection: Negative ion detection Measurement mode: SRM (Selected reaction monitoring) Monitor ions: Dehydroabietinic acid * (Q1 m / z 299.2, Q3 m / z 299.2) Dihydroabietic acid * (Q1 m / z303.2, Q3 m / z303.2) *[MH] - Set to monitor ions. Measurement conditions for other anionic surfactants (fatty acid compound (G)) used in Examples and Comparative Examples: HPLC: LC-20A [manufactured by Shimadzu Corporation] Mass spectrometer: API5000 [manufactured by SCIEX] Column: ODS column Mobile phase: A. 5 mmol / L ammonium acetate aqueous solution B. Methanol - tetrahydrofuran (1:1) Gradient conditions Injection volume: 5 μL Ionization: APCI Detection: Negative ion detection Measurement mode: SRM (Selected reaction monitoring) Monitor ions: Oleic acid * (Q1 m / z281.2, Q3 m / z281.2) Palmitic acid * (Q1 m / z255.2, Q3 m / z255.2) *[M - H] - Set as monitor ions In addition, when using other anionic surfactants other than the fatty acid compound (G) used in Examples and Comparative Examples, select the top two measurement target molecular species with high content contained in the other anionic surfactant as monitor ions, and calculate the content of the other anionic surfactant by the same method as above.

[0141] (4) Impact resistance evaluation (Charpy impact strength) After drying the resin composition pellets as samples in a hot air dryer at 80°C for 3 hours, they were filled into a SE-50DU molding machine manufactured by Sumitomo Heavy Industries, Ltd. with the cylinder temperature set at 230°C, and dumbbell test pieces with a thickness of 4 mm were molded at a mold temperature of 60°C and a molding cycle of 30 seconds. For each of the obtained 5 dumbbell test pieces, the Charpy impact strength was measured by a method compliant with ISO179, and the number average value was calculated.

[0142] (5) Surface smoothness evaluation (gloss) The resin composition pellets, which were the sample, were dried in a hot air dryer at 80°C for 3 hours. Then, they were filled into a Sumitomo Heavy Industries, Ltd. SE-50DU molding machine with the cylinder temperature set to 250°C, and rectangular plate molded products (90 mm long, 50 mm wide, 2.5 mm thick) were molded at an injection speed of 50 mm / s, a mold temperature of 60°C, and a molding cycle of 20 seconds. For each of the five obtained rectangular plate molded products, the glossiness at 20° was measured in accordance with JIS Z 8741 (established in 1997), and the numerical average was calculated.

[0143] (6) Color development evaluation (L value) The resin composition pellets, which served as the sample, were dried in a hot air dryer at 80°C for 3 hours. They were then filled into a Sumitomo Heavy Industries, Ltd. SE-50DU molding machine with the cylinder temperature set to 250°C. Square plate molded products (90mm long, 50mm wide, 2.5mm thick) were formed at an injection speed of 50mm / s, a mold temperature of 60°C, and a molding cycle of 20 seconds. The L value was measured for each of the five resulting square plate molded products in accordance with JIS K7103 (established in 1971), and the number-average value was calculated. A lower L value indicates a better result.

[0144] (7) Appearance evaluation of molded products (mold contamination) The resin composition pellets, which served as the sample, were dried in a hot air dryer at 80°C for 3 hours. They were then filled into a PS-60E molding machine manufactured by Nissei Plastic Industrial Co., Ltd., with the cylinder temperature set to 280°C. After 1000 injection moldings of rectangular plate molded products (100mm long, 120mm wide, 3mm thick) at a mold temperature of 60°C and a molding cycle of 30 seconds, the mold contamination was evaluated according to the following criteria. A represents the best result. No changes observed on the mold surface: A Cloudiness is visible on the mold surface: B The mold surface is dirty, resulting in a poor appearance of the molded product: C (8) Heat resistance evaluation The resin composition pellets, which were the sample, were dried in a hot air dryer at 80°C for 3 hours. Then, they were filled into a Sumitomo Heavy Industries, Ltd. SE-50DU molding machine with the cylinder temperature set to 230°C. Dumbbell test pieces with a thickness of 4 mm were molded at a mold temperature of 60°C and a molding cycle of 30 seconds. For each of the three resulting dumbbell test pieces, the heat distortion temperature was measured in accordance with ISO 75-2 (established in 2004, under a load of 1.8 MPa), and the average value was calculated.

[0145] (9) Morphological evaluation The resin composition pellets, which were the sample, were dried in a hot air dryer at 80°C for 3 hours. Then, they were filled into a Sumitomo Heavy Industries, Ltd. SE-50DU molding machine with the cylinder temperature set to 230°C. A 4mm thick dumbbell-shaped test piece was molded at a mold temperature of 60°C and a molding cycle of 30 seconds. The resulting dumbbell test piece was prepared by osmic acid staining, and its morphology was observed at 2500x magnification using a Hitachi High-Tech Corporation transmission electron microscope (TEM) HT7700 to observe the presence or absence of large-particle rubber particles (over 1 μm) of the rubbery polymer (R). The black areas in the TEM image represent the rubbery polymer (R). The white areas represent components other than the rubbery polymer (R).

[0146] The surfactants used in the examples and comparative examples are as follows:

[0147] Sulfosuccinate compounds (E): • Kohacool L-300 aqueous solution (solid content concentration 30% by mass) manufactured by Toho Chemical Industry Co., Ltd. (E-1).

[0148] Disproportionated rosin (F): • Diprosin K-25 aqueous solution (solid content concentration 25% by mass) manufactured by Toho Chemical Industry Co., Ltd. (F-1).

[0149] Other anionic surfactants: (Fatty acid compound (G)) In a 30 L reaction vessel equipped with a stirrer, 3.2 parts by mass of potassium hydroxide was dissolved in 81 parts by mass of pure water, and the aqueous solution was heated to 80°C. Then, 15.7 parts by mass of 45° hydrogenated beef tallow fatty acids manufactured by NOF Corporation were added over 30 minutes, and the mixture was stirred for 2 hours to obtain an aqueous solution of fatty acid compounds (solid content concentration 18% by mass) (G-1) as "other anionic surfactants".

[0150] (Other anionic surfactants (H) other than fatty acid compounds (G): • Alscope TH-330K (generic name: sodium polyoxyethylene lauryl ether sulfate) aqueous solution (solid content concentration 27% by mass) manufactured by Toho Chemical Industry Co., Ltd. (H-1) • Alscope LS-30 (generic name: sodium lauryl sulfate) aqueous solution (solid content concentration 30% by mass) manufactured by Toho Chemical Industry Co., Ltd. (H-2) • Neopellex G-65 (generic name: sodium dodecylbenzenesulfonate) paste (solid content concentration 65% by mass) manufactured by Kao Corporation (H-3).

[0151] (Manufacturing Example 1) Rubber polymer (R-1) and graft copolymer (A-1) 20m with a stirrer 3In the reaction vessel, 140 parts by mass of pure water (including water contained in the emulsifier), 0.2 parts by mass of Kohacool L-300 aqueous solution (E-1) as an emulsifier (based on solid content, i.e., (0.2 × (1 / 0.3)) parts by mass of aqueous solution), 0.7 parts by mass of Diprosin K-25 aqueous solution (F-1) as a solid content, and 0.1 parts by mass of sodium hydroxide were charged, and the inside of the vessel was purged with nitrogen. Then, the temperature was raised to 62°C, and under stirring, a mixture of 14.9 parts by mass of n-butyl acrylate and 0.1 parts by mass of allyl methacrylate was added at a constant rate over 30 minutes. Next, 0.2 parts by mass (based on solid content) of a 2% by mass potassium persulfate aqueous solution was added at a constant rate over 4.75 hours to start polymerization. Furthermore, 1.75 hours after the start of adding the potassium persulfate aqueous solution, a mixture of 42.3 parts by mass of n-butyl acrylate and 0.2 parts by mass of allyl methacrylate was added at a constant rate over 1.25 hours, followed by the addition of a mixture of 41.6 parts by mass of n-butyl acrylate and 0.9 parts by mass of allyl methacrylate at a constant rate over 1.25 hours. Additionally, 3 hours after the start of adding the potassium persulfate aqueous solution, 0.8 parts by mass of diprosin K-25 aqueous solution (F-1) was added at a constant rate over 1.75 hours, based on solid content. During this time, the temperature was raised to 65°C 2.25 hours after the start of adding the potassium persulfate aqueous solution, to 68°C 3 hours after the start of adding the potassium persulfate aqueous solution, and to 70°C 4 hours after the start of adding the potassium persulfate aqueous solution. The mixture was held for 0.5 hours after the completion of adding the potassium persulfate aqueous solution to obtain the latex of the rubbery polymer (R-1).

[0152] Next, 50 parts by mass of rubber polymer (R-1) latex (based on solid content), a mixture of 0.48 parts by mass of anhydrous glucose, 0.26 parts by mass of sodium pyrophosphate, and 0.01 parts by mass of ferrous sulfate, and as an emulsifier, 0.7 parts by mass of an aqueous solution of fatty acid compound (G-1) (based on solid content) and 115 parts by mass of pure water (including the water contained in the rubber polymer (R-1) latex and emulsifier) ​​were charged into the reaction vessel. After purging with nitrogen, the temperature was lowered to 60°C, and under stirring, a mixture of 6.6 parts by mass of styrene, 2.4 parts by mass of acrylonitrile, and 0.043 parts by mass of t-dodecyl mercaptan was added over 30 minutes.

[0153] Next, an initiator mixture consisting of 0.17 parts by mass of cumene hydroperoxide, 1.0 part by mass (solid content equivalent) of an aqueous solution of a fatty acid compound (G-1) acting as an emulsifier, and 8 parts by mass of pure water (including the water contained in the aqueous solution of the fatty acid compound (G-1) acting as an emulsifier) ​​was added dropwise over 3.5 hours. Subsequently, an initiator mixture consisting of 0.17 parts by mass of cumene hydroperoxide, 0.2 parts by mass (solid content equivalent) of an aqueous solution of a fatty acid compound (G-1) acting as an emulsifier, and 3.5 parts by mass of pure water (including the water contained in the aqueous solution of the fatty acid compound (G-1) acting as an emulsifier) ​​was added dropwise over 1.5 hours, for a total of 5 hours. Simultaneously with this addition, and in parallel with this addition, a mixture of 29.9 parts by mass of styrene, 11.1 parts by mass of acrylonitrile, and 0.20 parts by mass of t-dodecyl mercaptan was added dropwise over 3.5 hours. During this time, the temperature was raised to 62°C simultaneously with the start of the dropwise addition of the initiator mixture, and then to 65°C 3.5 hours after the start of the dropwise addition of the initiator mixture. Polymerization was completed when the dropwise addition of the initiator mixture was finished. After polymerization was completed, the product was cooled to 40°C, and while stirring, 0.75 parts by mass of the butylated reaction product of p-cresol and dicyclopentadiene (CAS Reg. No. 68610-51-5) and 0.2 parts by mass of phosphanol SC-6103L (main component: polyoxyethylene alkyl ether calcium phosphate) manufactured by Toho Chemical Industry Co., Ltd. were added to obtain the graft copolymer (A-1) latex. Subsequently, the latex of the obtained graft copolymer (A-1) was poured while stirring into dilute sulfuric acid at 60°C, which had been adjusted to a concentration of 0.38% by mass after the addition of the latex of the graft copolymer (A-1). After addition, the temperature was raised to 93°C to solidify, and then it was neutralized with 3.5 parts by mass of a 20% by mass aqueous sodium hydroxide solution (based on solid content), washed with water, centrifuged, and dried to obtain graft copolymer (A-1). The volume-average particle size of the obtained rubbery polymer (R-1) was 0.125 μm. The grafting rate of the graft copolymer (A-1) was 38%.

[0154] (Manufacturing Example 2) Rubber polymer (R-2) and graft copolymer (A-2) Latex of rubbery polymer (R-2) was obtained in the same manner as in Production Example 1, except that the emulsifiers initially added to the reaction vessel (in Production Example 1, 0.2 parts by mass of Kohacool L-300 aqueous solution (E-1) and 0.7 parts by mass of Diprosin K-25 aqueous solution (F-1) were added on a solid content basis) were changed to 0.2 parts by mass of Kohacool L-300 aqueous solution (E-1) and 1.2 parts by mass of Diprosin K-25 aqueous solution (F-1) on a solid content basis. Subsequently, latex of graft copolymer (A-2) was obtained in the same manner as in Production Example 1, except that latex of rubbery polymer (R-2) was used instead of latex of rubbery polymer (R-1). After that, graft copolymer (A-2) was obtained in the same manner as in Production Example 1. The volume-average particle size of the obtained rubbery polymer (R-2) was 0.13 μm. Furthermore, the grafting rate of the graft copolymer (A-2) was 36%.

[0155] (Manufacturing Example 3) Rubber polymer (R-3) and graft copolymer (A-3) Latex of rubbery polymer (R-3) was obtained in the same manner as in Production Example 1, except that the emulsifiers initially added to the reaction vessel (in Production Example 1, 0.2 parts by mass of Kohacool L-300 aqueous solution (E-1) and 0.7 parts by mass of Diprosin K-25 aqueous solution (F-1) were added on a solid content basis) were changed to 0.2 parts by mass of Kohacool L-300 aqueous solution (E-1) and 2.2 parts by mass of Diprosin K-25 aqueous solution (F-1) on a solid content basis. Subsequently, latex of graft copolymer (A-3) was obtained in the same manner as in Production Example 1, except that the latex of rubbery polymer (R-3) was used instead of the latex of rubbery polymer (R-1). After that, graft copolymer (A-3) was obtained in the same manner as in Production Example 1. The volume-average particle size of the obtained rubbery polymer (R-3) was 0.145 μm. Furthermore, the grafting rate of the graft copolymer (A-3) was 34%.

[0156] (Manufacturing Example 4) Rubber polymer (R-4) and graft copolymer (A-4) Latex of rubbery polymer (R-4) was obtained in the same manner as in Production Example 1, except that the emulsifiers initially added to the reaction vessel (in Production Example 1, 0.2 parts by mass of Kohacool L-300 aqueous solution (E-1) and 0.7 parts by mass of Diprosin K-25 aqueous solution (F-1) were added on a solid content basis) were changed to 0.3 parts by mass of Kohacool L-300 aqueous solution (E-1) and 0.7 parts by mass of Diprosin K-25 aqueous solution (F-1) on a solid content basis. Subsequently, latex of graft copolymer (A-4) was obtained in the same manner as in Production Example 1, except that the latex of rubbery polymer (R-4) was used instead of the latex of rubbery polymer (R-1). After that, graft copolymer (A-4) was obtained in the same manner as in Production Example 1. The volume-average particle size of the obtained rubbery polymer (R-4) was 0.105 μm. Furthermore, the grafting rate of the graft copolymer (A-4) was 41%.

[0157] (Manufacturing Example 5) Rubber polymer (R-5) and graft copolymer (A-5) Latex of rubbery polymer (R-5) was obtained in the same manner as in Production Example 1, except that the emulsifiers initially added to the reaction vessel (in Production Example 1, 0.2 parts by mass of Kohacool L-300 aqueous solution (E-1) and 0.7 parts by mass of Diprosin K-25 aqueous solution (F-1) were added on a solid content basis) were changed to 0.3 parts by mass of Kohacool L-300 aqueous solution (E-1) and 1.2 parts by mass of Diprosin K-25 aqueous solution (F-1) on a solid content basis. Subsequently, latex of graft copolymer (A-5) was obtained in the same manner as in Production Example 1, except that the latex of rubbery polymer (R-5) was used instead of the latex of rubbery polymer (R-1). After that, graft copolymer (A-5) was obtained in the same manner as in Production Example 1. The volume-average particle size of the obtained rubbery polymer (R-5) was 0.11 μm. Furthermore, the grafting rate of the graft copolymer (A-5) was 39%.

[0158] (Manufacturing Example 6) Rubber polymer (R-6) and graft copolymer (A-6) Latex of rubbery polymer (R-6) was obtained in the same manner as in Production Example 1, except that the emulsifiers initially added to the reaction vessel (in Production Example 1, 0.2 parts by mass of Kohacool L-300 aqueous solution (E-1) and 0.7 parts by mass of Diprosin K-25 aqueous solution (F-1) were added on a solid content basis) were changed to 0.3 parts by mass of Kohacool L-300 aqueous solution (E-1) and 2.2 parts by mass of Diprosin K-25 aqueous solution (F-1) on a solid content basis. Subsequently, latex of graft copolymer (A-6) was obtained in the same manner as in Production Example 1, except that the latex of rubbery polymer (R-6) was used instead of the latex of rubbery polymer (R-1). After that, graft copolymer (A-6) was obtained in the same manner as in Production Example 1. The volume-average particle size of the obtained rubbery polymer (R-6) was 0.125 μm. Furthermore, the grafting rate of the graft copolymer (A-6) was 37%.

[0159] (Manufacturing Example 7) Rubber polymer (R-7) and graft copolymer (A-7) Latex of rubbery polymer (R-7) was obtained in the same manner as in Production Example 1, except that the emulsifiers initially added to the reaction vessel (in Production Example 1, 0.2 parts by mass of Kohacool L-300 aqueous solution (E-1) and 0.7 parts by mass of Diprosin K-25 aqueous solution (F-1) were added on a solid content basis) were changed to 0.4 parts by mass of Kohacool L-300 aqueous solution (E-1) and 0.7 parts by mass of Diprosin K-25 aqueous solution (F-1) on a solid content basis. Subsequently, latex of graft copolymer (A-7) was obtained in the same manner as in Production Example 1, except that latex of rubbery polymer (R-7) was used instead of latex of rubbery polymer (R-1). After that, graft copolymer (A-7) was obtained in the same manner as in Production Example 1. The volume-average particle size of the obtained rubbery polymer (R-7) was 0.1 μm. Furthermore, the grafting rate of the graft copolymer (A-7) was 43%.

[0160] (Manufacturing Example 8) Rubber polymer (R-8) and graft copolymer (A-8) Latex of rubbery polymer (R-8) was obtained in the same manner as in Production Example 1, except that the emulsifiers initially added to the reaction vessel (in Production Example 1, 0.2 parts by mass of Kohacool L-300 aqueous solution (E-1) and 0.7 parts by mass of Diprosin K-25 aqueous solution (F-1) were added on a solid content basis) were changed to 0.4 parts by mass of Kohacool L-300 aqueous solution (E-1) and 2.2 parts by mass of Diprosin K-25 aqueous solution (F-1) on a solid content basis. Subsequently, latex of graft copolymer (A-8) was obtained in the same manner as in Production Example 1, except that latex of rubbery polymer (R-8) was used instead of latex of rubbery polymer (R-1). After that, graft copolymer (A-8) was obtained in the same manner as in Production Example 1. The volume-average particle size of the obtained rubbery polymer (R-8) was 0.105 μm. Furthermore, the grafting rate of the graft copolymer (A-8) was 42%.

[0161] (Manufacturing Example 9) Rubber polymer (R-9) and graft copolymer (A-9) In the first step, the emulsifier added to the reaction vessel (in Production Example 1, 0.2 parts by mass of Kohacool L-300 aqueous solution (E-1) and 0.7 parts by mass of Diprosin K-25 aqueous solution (F-1) were added on a solid content basis) was changed to 1.7 parts by mass of Kohacool L-300 aqueous solution (E-1) on a solid content basis, and the emulsifier added 3 hours after the start of potassium persulfate aqueous solution addition (0.8 parts by mass of Diprosin K-25 aqueous solution (F-1) on a solid content basis) was changed to 0.8 parts by mass of Kohacool L-300 aqueous solution (E-1) on a solid content basis, except that the latex of the rubbery polymer (R-9) was used instead of the latex of the rubbery polymer (R-1), the latex of the graft copolymer (A-9) was obtained in the same manner as in Production Example 1. Subsequently, graft copolymer (A-9) was obtained in the same manner as in Production Example 1, except that the latex of graft copolymer (A-9) was used instead of the latex of graft copolymer (A-1), and an aqueous calcium chloride solution adjusted to a concentration of 0.3% by mass after latex addition was used instead of dilute sulfuric acid adjusted to a concentration of 0.38% by mass after latex addition. The volume-average particle size of the obtained rubbery polymer (R-9) was 0.09 μm. The grafting rate of graft copolymer (A-9) was 45%. The aqueous calcium chloride solution was used because coagulation did not occur with dilute sulfuric acid.

[0162] (Manufacturing Example 10) Rubber polymer (R-10) and graft copolymer (A-10) Latex of rubbery polymer (R-10) was obtained in the same manner as in Production Example 1, except that the emulsifier added to the reaction vessel at the beginning (in Production Example 1, 0.2 parts by mass of Kohacool L-300 aqueous solution (E-1) and 0.7 parts by mass of Diprosin K-25 aqueous solution (F-1) were added in solid content terms) was changed to 1.7 parts by mass of Diprosin K-25 aqueous solution (F-1) in solid content terms. Subsequently, latex of graft copolymer (A-10) was obtained in the same manner as in Production Example 1, except that latex of rubbery polymer (R-10) was used instead of latex of rubbery polymer (R-1). Graft copolymer (A-10) was then obtained in the same manner as in Production Example 1. The volume-average particle size of the obtained rubbery polymer (R-10) was 0.16 μm. The grafting rate of graft copolymer (A-10) was 25%.

[0163] (Manufacturing Example 11) Rubber polymer (R-11) and graft copolymer (A-11) Latex of rubbery polymer (R-11) was obtained in the same manner as in Production Example 1, except that the emulsifiers initially added to the reaction vessel (in Production Example 1, 0.2 parts by mass of Kohacool L-300 aqueous solution (E-1) and 0.7 parts by mass of Diprosin K-25 aqueous solution (F-1) were added on a solid content basis) were changed to 0.1 parts by mass of Kohacool L-300 aqueous solution (E-1) and 0.4 parts by mass of Diprosin K-25 aqueous solution (F-1) on a solid content basis. Subsequently, latex of graft copolymer (A-11) was obtained in the same manner as in Production Example 1, except that latex of rubbery polymer (R-11) was used instead of latex of rubbery polymer (R-1). After that, graft copolymer (A-11) was obtained in the same manner as in Production Example 1. The volume-average particle size of the obtained rubbery polymer (R-11) was 0.165 μm. Furthermore, the grafting rate of the graft copolymer (A-11) was 27%.

[0164] (Manufacturing Example 12) Rubber polymer (R-12) and graft copolymer (A-12) Latex of rubbery polymer (R-12) was obtained in the same manner as in Production Example 1, except that the emulsifiers initially added to the reaction vessel (in Production Example 1, 0.2 parts by mass of Kohacool L-300 aqueous solution (E-1) and 0.7 parts by mass of Diprosin K-25 aqueous solution (F-1) were added on a solid content basis) were changed to 0.1 parts by mass of Kohacool L-300 aqueous solution (E-1) and 1.2 parts by mass of Diprosin K-25 aqueous solution (F-1) on a solid content basis. Subsequently, latex of graft copolymer (A-12) was obtained in the same manner as in Production Example 1, except that latex of rubbery polymer (R-12) was used instead of latex of rubbery polymer (R-1). After that, graft copolymer (A-12) was obtained in the same manner as in Production Example 1. The volume-average particle size of the obtained rubbery polymer (R-12) was 0.145 μm. Furthermore, the grafting rate of the graft copolymer (A-12) was 44%.

[0165] (Manufacturing Example 13) Rubber polymer (R-13) and graft copolymer (A-13) Latex of rubbery polymer (R-13) was obtained in the same manner as in Production Example 1, except that the emulsifiers initially added to the reaction vessel (in Production Example 1, 0.2 parts by mass of Kohacool L-300 aqueous solution (E-1) and 0.7 parts by mass of Diprosin K-25 aqueous solution (F-1) on a solid content basis) were changed to 0.5 parts by mass of Kohacool L-300 aqueous solution (E-1) and 1.2 parts by mass of Diprosin K-25 aqueous solution (F-1) on a solid content basis. Subsequently, latex of graft copolymer (A-13) was obtained in the same manner as in Production Example 1, except that latex of rubbery polymer (R-13) was used instead of latex of rubbery polymer (R-1). Subsequently, graft copolymer (A-13) was obtained in the same manner as in Production Example 1, except that the latex of graft copolymer (A-13) was used instead of the latex of graft copolymer (A-1), and an aqueous calcium chloride solution adjusted to a concentration of 0.3% by mass after latex addition was used instead of dilute sulfuric acid adjusted to a concentration of 0.38% by mass after latex addition. The volume-average particle size of the obtained rubbery polymer (R-13) was 0.125 μm. The grafting rate of graft copolymer (A-13) was 44%. The aqueous calcium chloride solution was used because coagulation did not occur with dilute sulfuric acid.

[0166] (Manufacturing Example 14) Rubber polymer (R-14) and graft copolymer (A-14) Latex of rubbery polymer (R-14) was obtained in the same manner as in Production Example 1, except that the emulsifiers initially added to the reaction vessel (in Production Example 1, 0.2 parts by mass of Kohacool L-300 aqueous solution (E-1) and 0.7 parts by mass of Diprosin K-25 aqueous solution (F-1) were changed to 0.3 parts by mass of Kohacool L-300 aqueous solution (E-1) and 0.2 parts by mass of Diprosin K-25 aqueous solution (F-1) based on solid content) were changed. Subsequently, latex of graft copolymer (A-14) was obtained in the same manner as in Production Example 1, except that latex of rubbery polymer (R-14) was used instead of latex of rubbery polymer (R-1). After that, graft copolymer (A-14) was obtained in the same manner as in Production Example 1. The volume-average particle size of the obtained rubbery polymer (R-14) was 0.115 μm. Furthermore, the grafting rate of the graft copolymer (A-14) was 39%.

[0167] (Manufacturing Example 15) Rubber polymer (R-15) and graft copolymer (A-15) Latex of rubbery polymer (R-15) was obtained in the same manner as in Production Example 1, except that the emulsifiers added to the reaction vessel initially (in Production Example 1, 0.2 parts by mass of Kohacool L-300 aqueous solution (E-1) and 0.7 parts by mass of Diprosin K-25 aqueous solution (F-1) were added on a solid content basis) were changed to 0.3 parts by mass of Kohacool L-300 aqueous solution (E-1) and 2.7 parts by mass of Diprosin K-25 aqueous solution (F-1) on a solid content basis. Subsequently, latex of graft copolymer (A-15) was obtained in the same manner as in Production Example 1, except that the latex of rubbery polymer (R-15) was used instead of the latex of rubbery polymer (R-1). After that, graft copolymer (A-15) was obtained in the same manner as in Production Example 1. The volume-average particle size of the obtained rubbery polymer (R-15) was 0.14 μm. Furthermore, the grafting rate of the graft copolymer (A-15) was 35%.

[0168] (Manufacturing Example 16) Rubber polymer (R-16) and graft copolymer (A-16) Latex of rubbery polymer (R-16) was obtained in the same manner as in Production Example 1, except that the emulsifiers initially added to the reaction vessel (in Production Example 1, 0.2 parts by mass of Kohacool L-300 aqueous solution (E-1) and 0.7 parts by mass of Diprosin K-25 aqueous solution (F-1) were added on a solid content basis) were replaced with 0.3 parts by mass of Alscope TH-330K aqueous solution (H-1) and 1.2 parts by mass of Diprosin K-25 aqueous solution (F-1) on a solid content basis. Subsequently, latex of graft copolymer (A-16) was obtained in the same manner as in Production Example 1, except that the latex of rubbery polymer (R-16) was used instead of the latex of rubbery polymer (R-1). Subsequently, graft copolymer (A-16) was obtained in the same manner as in Production Example 1, except that the latex of graft copolymer (A-16) was used instead of the latex of graft copolymer (A-1), and an aqueous calcium chloride solution adjusted to a concentration of 0.3% by mass after latex addition was used instead of dilute sulfuric acid adjusted to a concentration of 0.38% by mass after latex addition. The volume-average particle size of the obtained rubbery polymer (R-16) was 0.1 μm. The grafting rate of graft copolymer (A-16) was 37%. The aqueous calcium chloride solution was used because coagulation did not occur with dilute sulfuric acid.

[0169] (Manufacturing Example 17) Rubber polymer (R-17) and graft copolymer (A-17) In the first step, the emulsifiers added to the reaction vessel (in Production Example 1, 0.2 parts by mass of Kohacool L-300 aqueous solution (E-1) and 0.7 parts by mass of Diprosin K-25 aqueous solution (F-1) were added on a solid content basis) were replaced with 0.3 parts by mass of Alscope LS-30 aqueous solution (H-2) and 1.2 parts by mass of Diprosin K-25 aqueous solution (F-1) on a solid content basis. The latex of the rubbery polymer (R-17) was obtained in the same manner as in Production Example 1. Subsequently, the latex of the graft copolymer (A-17) was obtained in the same manner as in Production Example 1, except that the latex of the rubbery polymer (R-17) was used instead of the latex of the rubbery polymer (R-1). Subsequently, graft copolymer (A-17) was obtained in the same manner as in Production Example 1, except that the latex of graft copolymer (A-17) was used instead of the latex of graft copolymer (A-1), and an aqueous calcium chloride solution adjusted to a concentration of 0.3% by mass after latex addition was used instead of dilute sulfuric acid adjusted to a concentration of 0.38% by mass after latex addition. The volume-average particle size of the obtained rubbery polymer (R-17) was 0.09 μm. The grafting rate of graft copolymer (A-17) was 35%. The aqueous calcium chloride solution was used because coagulation did not occur with dilute sulfuric acid.

[0170] (Manufacturing Example 18) Rubber polymer (R-18) and graft copolymer (A-18) In the first step, the emulsifiers added to the reaction vessel (in Production Example 1, 0.2 parts by mass of Kohacool L-300 aqueous solution (E-1) and 0.7 parts by mass of Diprosin K-25 aqueous solution (F-1) were added on a solid content basis) were replaced with 0.3 parts by mass of Neoperex G-65 paste (H-3) and 1.2 parts by mass of Diprosin K-25 aqueous solution (F-1) on a solid content basis. The latex of the rubbery polymer (R-18) was obtained in the same manner as in Production Example 1. Subsequently, the latex of the graft copolymer (A-18) was obtained in the same manner as in Production Example 1, except that the latex of the rubbery polymer (R-18) was used instead of the latex of the rubbery polymer (R-1). Subsequently, graft copolymer (A-18) was obtained in the same manner as in Production Example 1, except that the latex of graft copolymer (A-18) was used instead of the latex of graft copolymer (A-1), and an aqueous calcium chloride solution adjusted to a concentration of 0.3% by mass after latex addition was used instead of dilute sulfuric acid adjusted to a concentration of 0.38% by mass after latex addition. The volume-average particle size of the obtained rubbery polymer (R-18) was 0.08 μm. The grafting rate of graft copolymer (A-18) was 33%. The aqueous calcium chloride solution was used because coagulation did not occur with dilute sulfuric acid.

[0171] Tables 1 and 2 show the amounts of sulfosuccinate compound (E), disproportionate rosin (F), other anionic surfactants, and the mass-based ratio of sulfosuccinate compound (E) to disproportionate rosin (F) per 100 parts by mass of monomer mixture (r) in step 1-A, the amount of anionic surfactant (fatty acid compound (G)) per 100 parts by mass of the total of the latex solids of the rubbery polymer (R) and monomer mixture (a) in step 1-B, and the type of coagulant used in step 1-C.

[0172] [Table 1]

[0173] [Table 2]

[0174] (Manufacturing Example 19) Vinyl Copolymer (B-1) A 2m condenser for the evaporation and carbonization of monomer vapors, with helical ribbon blades. 3 Using a continuous bulk polymerization apparatus consisting of a fully mixed polymerization tank, a single-screw extruder preheater, and a twin-screw extruder demonomerizer, vinyl copolymer (B-1) was produced by the following method.

[0175] First, a mixture consisting of 72 parts by mass of styrene, 28 parts by mass of acrylonitrile, 0.2 parts by mass of n-octyl mercaptan, and 0.015 parts by mass of 1,1-bis(t-butylperoxy)cyclohexane was continuously supplied at 150 kg / hour to a fully mixed polymerization tank, and continuous bulk polymerization was carried out while maintaining the polymerization temperature at 130°C and the tank pressure at 0.08 MPa. The polymerization rate of the polymerization reaction mixture at the outlet of the fully mixed polymerization tank was controlled to 65 ± 3%.

[0176] Next, the polymerization reaction mixture was preheated using a single-screw extruder preheater, then supplied to a twin-screw extruder demonomerizer, where unreacted monomers were recovered by vacuum evaporation from the vent of the twin-screw extruder demonomerizer. The recovered unreacted monomers were continuously refluxed to a complete mixing polymerization tank. The styrene / acrylonitrile copolymer, which had an apparent polymerization rate of 99% or more, was melt-kneaded at 150 kg / hour. The molten mixture was extruded in strand form and cut with a cutter to obtain 3 mm long vinyl copolymer (B-1) (copolymerization ratio: 72% by mass from styrene monomers, 28% by mass from acrylonitrile monomers). The weight-average molecular weight of the obtained vinyl copolymer (B-1) was 128,000.

[0177] (Manufacturing Example 20) Heat-resistant vinyl copolymer (C-1) In a 30 L autoclave equipped with a stirrer, 65 parts by mass of styrene, 7 parts by mass of maleic anhydride, 0.3 parts by mass of 2,4-diphenyl-4-methyl-1-pentene, and 25 parts by mass of methyl ethyl ketone were charged. After purging the system with nitrogen gas, the temperature was raised to 92°C, and a solution of 28 parts by mass of maleic anhydride and 0.18 parts by mass of t-butyl peroxy-2-ethylhexanoate dissolved in 100 parts by mass of methyl ethyl ketone was continuously added over 7 hours. After the addition, 0.03 parts by mass of t-butyl peroxy-2-ethylhexanoate was further added, the temperature was raised to 120°C, and the mixture was reacted for another hour to obtain a polymer solution of styrene-maleic anhydride copolymer. Next, 32 parts by mass of aniline and 0.6 parts by mass of triethylamine were added to the polymer solution and the mixture was reacted at 140°C for 7 hours. The polymer solution after the imidization reaction was supplied to a vented screw extruder to remove volatile components and obtain a pellet-shaped heat-resistant vinyl copolymer (C-1) (copolymerization ratio: 51% by mass from styrene monomer, 48% by mass from N-phenylmaleimide monomer, and 1% by mass from maleic anhydride monomer). The reduced viscosity (ηsp / c) of the obtained heat-resistant vinyl copolymer (C-1) was 0.46 dl / g.

[0178] (Examples 1-8, Comparative Examples 1-10) Graft copolymer (A) and vinyl copolymer (B) were blended in the proportions shown in Table 3 or Table 4. To 100 parts by mass of these materials, 1.5 parts by mass of carbon black, 1 part by mass of ethylenebisstearamide, 0.3 parts by mass of bis(2,2,6,6-tetramethyl-4-piperidinyl) sebacate, 0.3 parts by mass of phenol,2-(2H-benzotriazole-2-yl)-4-methyl, and 0.15 parts by mass of octadecyl-3-(3,5-di-tetrabutyl-4-hydroxyphenyl)propionate were added. The resulting mixture was melt-kneaded in a twin-screw extruder with a screw diameter of 30 mm and rotating in the same direction (temperature range 240-260°C) to obtain pellets.

[0179] (Example 9, Comparative Examples 11-13) Graft copolymer (A), vinyl copolymer (B), and heat-resistant vinyl copolymer (C) were blended in the proportions shown in Table 3 or Table 4. To 100 parts by mass of these mixtures, 1.5 parts by mass of carbon black, 1 part by mass of ethylenebis-stearamide, 0.3 parts by mass of bis(2,2,6,6-tetramethyl-4-piperidinyl) sebacate, 0.3 parts by mass of phenol,2-(2H-benzotriazole-2-yl)-4-methyl, and 0.15 parts by mass of octadecyl-3-(3,5-di-tetrabutyl-4-hydroxyphenyl)propionate were added. The resulting mixture was melt-kneaded in a twin-screw extruder with a screw diameter of 30 mm and rotating in the same direction (temperature range 240-260°C) to obtain pellets.

[0180] [Table 3]

[0181] [Table 4]

[0182] The resin compositions of Examples 1-8 have a Charpy impact strength of 7 kJ / m². 2 In summary, the gloss level was 80% or higher, the L value was 7.5 or lower, the mold contamination resistance was rated B or higher, and the product exhibited excellent impact resistance, surface smoothness, color development, and molded product appearance.

[0183] On the other hand, Comparative Example 1 did not incorporate disproportionated rosin (F) in step 1-A, resulting in inferior impact resistance and molded product appearance; Comparative Example 2 did not incorporate sulfosuccinate compound (E) in step 1-A, resulting in inferior surface smoothness and color development; Comparative Example 3 had insufficient amounts of sulfosuccinate compound (E) and disproportionated rosin (F) in step 1-A, resulting in inferior surface smoothness and color development; Comparative Example 4 had insufficient amounts of sulfosuccinate compound (E) in step 1-A, resulting in inferior surface smoothness and color development; Comparative Example 5 had an excessive amount of sulfosuccinate compound (E) in step 1-A, resulting in inferior impact resistance and molded product appearance; Comparative Example 6 had insufficient amounts of disproportionated rosin (F) in step 1-A, resulting in inferior impact resistance; and Comparative Example 7 had an excessive amount of disproportionated rosin (F), resulting in inferior surface smoothness and color development. Comparative Example 8, which did not include sulfosuccinate compound (E) in step 1-A, but instead included an aqueous solution of sodium polyoxyethylene lauryl ether sulfate (H-1), another anionic surfactant, resulted in inferior impact resistance and molded product appearance. Comparative Example 9, which did not include sulfosuccinate compound (E) in step 1-A, but instead included an aqueous solution of sodium lauryl sulfate (H-2), another anionic surfactant, also resulted in inferior impact resistance and molded product appearance. Comparative Example 10, which did not include sulfosuccinate compound (E) in step 1-A, but instead included a paste of sodium dodecylbenzenesulfonate (H-3), another anionic surfactant, also resulted in inferior impact resistance and molded product appearance.

[0184] The resin composition of Example 9, although having reduced impact resistance, can be given heat resistance, and has a Charpy impact strength of 5 kJ / m². 2 In summary, the gloss level was 80% or higher, the L value was 7.5 or lower, the mold contamination resistance was rated B or higher, and the heat distortion temperature was 90°C or higher, demonstrating excellent impact resistance, surface smoothness, color development, molded product appearance, and heat resistance.

[0185] On the other hand, Comparative Example 11 did not contain disproportionated rosin (F) in step 1-A, and like Comparative Example 1, it had poor impact resistance and molded product appearance. Comparative Example 12 did not contain sulfosuccinate compound (E) in step 1-A, and like Comparative Example 2, it had poor surface smoothness and color development. Comparative Example 13 contained an excessive amount of disproportionated rosin (F), and like Comparative Example 7, it had poor surface smoothness and color development.

[0186] Furthermore, morphological observation of the resin compositions revealed that in Comparative Example 2, large-particle rubber with a particle diameter exceeding 1 μm was observed, as shown in Figure 1. Similar large-particle rubber with a particle diameter exceeding 1 μm was also observed in Comparative Examples 3, 4, and 9. [Explanation of symbols]

[0187] 1: Large-particle rubber with a particle size exceeding 1 μm

Claims

1. Step 1: A step to obtain a graft copolymer (A) by performing the following steps 1-A to 1-C in this order. Step 1-A: A step to obtain a latex rubber polymer (R) by copolymerizing 100 parts by mass of a monomer mixture (r) consisting of 97 to 99.5 parts by mass of an alkyl acrylate monomer (r1) and 0.5 to 3 parts by mass of a polyfunctional monomer (r2) in the presence of 0.15 to 0.45 parts by mass of a sulfosuccinate compound (E) represented by the following chemical formula [1] and 1.5 to 3 parts by mass of disproportionating rosin (F) as an emulsifier. 【Chemistry 1】 (R is an alkyl or alkenyl group having 8 to 22 carbon atoms, AO is an oxyalkylene group having 2 or 3 carbon atoms, n is an integer from 0 to 20, M and N are independently hydrogen, an alkali metal, or an alkaline earth metal, p is 1 when M is hydrogen or an alkali metal, and 1 / 2 when M is an alkaline earth metal, and q is 1 when N is hydrogen or an alkali metal, and 1 / 2 when N is an alkaline earth metal.) Step 1-B: In the presence of the latex of the rubbery polymer (R), a monomer mixture (a) containing at least an aromatic vinyl monomer (a1) and a vinyl cyanide monomer (a2) is graft copolymerized with the rubbery polymer (R) to obtain a latex of the graft copolymer (A). Step 1-C: A step of contacting the latex of the graft copolymer (A) with an acid, then neutralizing it with an alkali, washing it with water, and dehydrating it to obtain the graft copolymer (A). Step 2: A step of copolymerizing a monomer mixture (b) containing at least an aromatic vinyl monomer (b1) and a vinyl cyanide monomer (b2) to obtain a vinyl copolymer (B), and, Step 3: A step of mixing the graft copolymer (A) obtained in Step 1 and the vinyl copolymer (B) obtained in Step 2. A method for producing a resin composition comprising the following: the proportion of the total amount of anionic surfactant contained in the resin composition is 5,000 ppm (mass / mass) or less of the total amount of the resin composition, and the proportion of the sulfosuccinate compound (E) represented by the chemical formula [1] and disproportionated rosin (F) contained in the resin composition is 2,000 ppm (mass / mass) or less of the total amount of the resin composition.

2. Furthermore, the method for producing a resin composition according to claim 1, comprising the following step 4 to obtain a heat-resistant vinyl copolymer (C), and the obtained heat-resistant vinyl copolymer (C) being mixed with the graft copolymer (A) and vinyl copolymer (B) in step 3 to obtain a resin composition. Step 4: A step of copolymerizing a monomer mixture (c) containing at least an aromatic vinyl monomer (c1) and a maleimide monomer (c2) to obtain a heat-resistant vinyl copolymer (C).

3. A method for producing a resin composition according to claim 1 or 2, characterized in that in step 1-A, a sulfosuccinate compound (E) and disproportionated rosin (F) are used in a mass ratio of 9:91 to 30:70 (sulfosuccinate compound (E): disproportionated rosin (F)).

4. A graft copolymer (A) is obtained by graft copolymerizing a monomer mixture (a) containing at least an aromatic vinyl monomer (a1) and a vinyl cyanide monomer (a2) in the presence of an acrylic rubber polymer (R) obtained by copolymerizing an alkyl acrylate monomer (r1) and a polyfunctional monomer (r2), and A resin composition comprising a vinyl copolymer (B) obtained by copolymerizing a monomer mixture (b) containing at least an aromatic vinyl monomer (b1) and a vinyl cyanide monomer (b2), The resin composition is characterized in that the total amount of anionic surfactant contained in the resin composition is 5,000 ppm (mass / mass) or less of the total amount of the resin composition, and the combined amount of sulfosuccinate compound (E) and disproportionated rosin (F) represented by the following chemical formula [1] contained in the resin composition is 2,000 ppm (mass / mass) or less of the total amount of the resin composition, and the ratio of the sulfosuccinate compound (E) to disproportionated rosin (F) is 10:90 to 30:70 (sulfosuccinate compound (E): disproportionated rosin (F)) by mass ratio. 【Chemistry 2】 (R is an alkyl or alkenyl group having 8 to 22 carbon atoms, AO is an oxyalkylene group having 2 or 3 carbon atoms, n is an integer from 0 to 20, M and N are independently hydrogen, an alkali metal, or an alkaline earth metal, p is 1 when M is hydrogen or an alkali metal, and 1 / 2 when M is an alkaline earth metal, and q is 1 when N is hydrogen or an alkali metal, and 1 / 2 when N is an alkaline earth metal.)

5. The resin composition according to claim 4, further characterized by containing a heat-resistant vinyl copolymer (C) obtained by copolymerizing a monomer mixture (c) containing at least an aromatic vinyl monomer (c1) and a maleimide monomer (c2).

6. A resin composition obtained by the method for producing a resin composition according to any one of claims 1 to 3, or a molded article obtained by molding a resin composition according to claim 4 or 5.

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