JP2019147867A - Thermoplastic resin composition and molded article thereof - Google Patents

Abstract

To provide a thermoplastic resin composition excellent in fluidity, heat resistance, impact resistance, color development, and scratch resistance.SOLUTION: The thermoplastic resin composition contains 28-48 mass% of a graft copolymer (A) and 52-72 mass% of a copolymer (B) based on 100 mass% of the total of the graft copolymer (A) and the copolymer (B). The graft copolymer (A) is obtained by graft-polymerizing one or more of an aromatic vinyl monomer and a vinyl cyanide monomer in the presence of an ethylene-α-olefin copolymer (a) having a volume average particle diameter of 180-550 nm and a gel content of 1-80 mass%. The copolymer (B) is a copolymer of an aromatic vinyl monomer, a (meth)acrylate monomer, and an unsaturated dicarboxylic acid anhydride monomer. The content of the aromatic vinyl monomer unit is 40-68 mass% based on 100 mass% of the total of the aromatic vinyl monomer unit, the (meth)acrylate monomer unit, and the unsaturated dicarboxylic acid anhydride monomer unit.SELECTED DRAWING: Figure 1

Description

  The present invention is a thermoplastic resin composition capable of providing a molded article excellent in fluidity, heat resistance, impact resistance, color development, and scratch resistance, and is formed by molding this thermoplastic resin composition. It relates to molded products.

  Improving the impact resistance of the molded product not only expands the applications of the molded product, but also makes it extremely useful for industrial applications, such as making it possible to reduce the thickness and size of the molded product. . Therefore, various techniques have been proposed so far for improving the impact resistance of the molded product. Among these methods, a method for increasing the impact resistance of a molded product by using a resin material in which a rubbery polymer and a hard resin are combined has already been industrialized. Examples of such resin materials include acrylonitrile-butadiene-styrene (ABS) resin, acrylonitrile-styrene-acrylic ester (ASA) resin, acrylonitrile-ethylene / propylene / non-conjugated diene copolymer-styrene (AES) resin, and the like. Can be mentioned.

  Moreover, when high designability is calculated | required by a molded article, the coating process is performed to the molded article obtained from these resin materials, and high appearance quality is obtained. However, the coating process has problems such as a large environmental load, complicated processes, and high manufacturing costs. Therefore, the coating treatment of the molded product may be omitted. In this case, in addition to mechanical properties such as impact resistance, the molded product is required to have scratch resistance that is not noticeable even when the scratch is attached.

  Furthermore, parts such as automobile grills are becoming larger and more complicated in shape, and high fluidity is required in order to improve moldability.

Resin materials from which molded articles with good impact resistance can be obtained include copolymers of methyl methacrylate, maleic anhydride, styrene, alkyl acrylate, copolymers of vinyl cyanide and aromatic vinyl, and rubber A polymer using a graft copolymer obtained by graft polymerization of vinyl cyanide and aromatic vinyl is known (Patent Document 1).
In addition, as a resin material capable of obtaining a molded article having good impact resistance and scratch resistance, a graft copolymer obtained by graft-polymerizing a specific monomer mixture to a crosslinked ethylene / α-olefin copolymer; , N-substituted maleimide or maleic anhydride, aromatic vinyl, and a methacrylic ester resin obtained by polymerizing a monomer mixture containing a methacrylic ester are known (Patent Document 2).

JP-A-2-272050 JP 2014-80525 A

However, since the thermoplastic resin composition described in Patent Document 1 uses butadiene rubber as the graft rubber component, the sliding property is low and the scratch resistance is poor.
The thermoplastic resin composition described in Patent Document 2 uses an ethylene / α-olefin copolymer as a graft rubber component, and thus has excellent slidability and scratch resistance. Low and moldability was poor.

  The present invention is a thermoplastic resin composition capable of providing a molded article excellent in fluidity, heat resistance, impact resistance, color development, and scratch resistance, and is formed by molding this thermoplastic resin composition. The object is to provide a molded product.

  The present invention solves the above problems and includes the following aspects.

[1] The following graft copolymer (A) and copolymer (B) are contained, and the graft copolymer is based on a total of 100% by mass of the graft copolymer (A) and the copolymer (B). A thermoplastic resin composition having a polymer (A) content of 28 to 48% by mass and a copolymer (B) of 52 to 72% by mass.
Graft copolymer (A): In the presence of ethylene / α-olefin copolymer (a), one or more monomers selected from the group consisting of aromatic vinyl monomers and vinyl cyanide monomers A graft copolymer obtained by polymerizing a vinyl monomer component (m1) containing a monomer;
The volume average particle diameter of the ethylene / α-olefin copolymer (a) constituting the graft copolymer (A) is 180 nm to 550 nm, and the gel content measured by the following measuring method is 1 to 80% by mass. Graft copolymer (A)
<Measurement method of gel content>
A sample [E1] 0.5 g of the ethylene / α-olefin copolymer (a) is immersed in 200 mL of 110 ° C. toluene for 5 hours to obtain a solution. Next, the solution is filtered through a 200 mesh wire net, the residue is dried, and the mass (g) of the dried product [E2] is measured. From the following formula (1), the gel content of the ethylene / α-olefin copolymer (a) is determined.
Gel content (% by mass) = [E2] / [E1] × 100 (1)
Copolymer (B): a copolymer obtained by polymerizing an aromatic vinyl monomer, a (meth) acrylic acid ester monomer, and an unsaturated dicarboxylic acid anhydride monomer,
With respect to a total of 100% by mass of the aromatic vinyl monomer unit, the (meth) acrylic acid ester monomer, and the unsaturated dicarboxylic acid anhydride monomer unit contained in the copolymer (B), Copolymer (B) having an aromatic vinyl monomer unit content of 40 to 68% by mass

[2] The ethylene unit α-olefin copolymer (a) has an ethylene unit content of 45 to 80% by mass, and the total content of the ethylene unit and the α-olefin unit is 90 to 100% by mass, The content of the aromatic vinyl monomer in 100% by mass of the vinyl monomer component (m1) is 60 to 80% by mass, and the content of the vinyl cyanide monomer is 15 to 40% by mass. Yes, the graft copolymer (A) is obtained by polymerizing 20 to 60% by mass of the vinyl monomer component (m1) on a 40 to 80% by mass loss seat plate of the ethylene / α-olefin copolymer (a). (However, the total of the ethylene / α-olefin copolymer (a) and the vinyl monomer component (m1) is 100% by mass), and the graft ratio is 20 to 100% [1]. The thermoplastic resin composition as described.

[3] The thermoplastic resin composition according to [1] or [2], which is a crosslinked ethylene / α-olefin copolymer (ac) obtained by crosslinking the ethylene / α-olefin copolymer (a).

[4] Total 100% by mass of the aromatic vinyl monomer unit, the (meth) acrylic acid ester monomer unit, and the unsaturated dicarboxylic anhydride monomer unit contained in the copolymer (B). In contrast, the content of the aromatic vinyl-based monomer unit is 40 to 68% by mass, the content of the (meth) acrylic acid ester-based monomer unit is 20 to 30% by mass, the unsaturated dicarboxylic acid anhydride unit The heat according to any one of [1] to [3], wherein the content of the monomer unit is 8 to 20% by mass, and the weight average molecular weight (Mw) of the copolymer (B) is 100,000 to 200,000. Plastic resin composition.

[5] A molded product obtained by molding the thermoplastic resin composition according to any one of [1] to [4].

The thermoplastic resin composition of the present invention is excellent in fluidity, and can provide a molded product excellent in heat resistance, impact resistance, color development and scratch resistance under good moldability.
For this reason, the thermoplastic resin composition and molded product thereof of the present invention are useful as vehicle interior / exterior parts, office equipment, home appliances, building materials and the like.

It is explanatory drawing of the evaluation method of scratch resistance in an Example.

  Hereinafter, embodiments of the present invention will be described in detail.

[Definition of terms]
The following definitions of terms apply throughout this specification and the claims.
“Molded product” means a product formed by molding a thermoplastic resin composition.
“Lightness (L ^* )” means a lightness value (L ^* ) among color values in the L ^* a ^* b ^* color system adopted in JIS Z 8729.
The “SCE method” means a method of measuring a color by using a spectrocolorimeter in accordance with JIS Z 8722 and removing specularly reflected light with an optical trap.
“Unit” refers to a structural portion derived from a monomer compound (monomer) before polymerization. For example, “acrylate monomer unit” refers to “acrylate monomer”. "Structural part".
“(Meth) acryl” refers to one or both of “acryl” and “methacryl”.

[Thermoplastic resin composition]
The thermoplastic resin composition of the present invention comprises the following graft copolymer (A) and copolymer (B) with respect to a total of 100% by mass of the graft copolymer (A) and copolymer (B). The graft copolymer (A) is contained in an amount of 28 to 48% by mass and the copolymer (B) is contained in an amount of 52 to 72% by mass. This specific graft copolymer (A) and Since the copolymer (B) is contained at a specific ratio, a molded product having excellent fluidity and excellent heat resistance, impact resistance, color development, and scratch resistance can be obtained.
Graft copolymer (A): In the presence of ethylene / α-olefin copolymer (a), one or more monomers selected from the group consisting of aromatic vinyl monomers and vinyl cyanide monomers A graft copolymer obtained by polymerizing a vinyl monomer component (m1) containing a monomer, and the ethylene / α-olefin copolymer (a) constituting the graft copolymer (A) Graft copolymer (A) (hereinafter referred to as “graft copolymer (A) of the present invention”) having a volume average particle size of 180 nm to 550 nm and a gel content of 1 to 80% by mass measured by the following measurement method. May be referred to.)

<Measurement method of gel content>
A sample [E1] 0.5 g of the ethylene / α-olefin copolymer (a) is immersed in 200 mL of 110 ° C. toluene for 5 hours to obtain a solution. Next, the solution is filtered through a 200 mesh wire net, the residue is dried, and the mass (g) of the dried product [E2] is measured. From the following formula (1), the gel content of the ethylene / α-olefin copolymer (a) is determined.
Gel content (% by mass) = [E2] / [E1] × 100 (1)

Copolymer (B): a copolymer obtained by polymerizing an aromatic vinyl monomer, a (meth) acrylic acid ester monomer, and an unsaturated dicarboxylic acid anhydride monomer. Aromatic with respect to a total of 100% by mass of the aromatic vinyl monomer unit, (meth) acrylic acid ester monomer, and unsaturated dicarboxylic acid anhydride monomer unit contained in the polymer (B). Copolymer (B) having a content of vinyl monomer units of 40 to 68% by mass (hereinafter sometimes referred to as “copolymer (B) of the present invention”).

[Graft Copolymer (A)]
The graft copolymer (A) of the present invention is a copolymer obtained by polymerizing the vinyl monomer component (m1) in the presence of the ethylene / α-olefin copolymer (a). In other words, the graft copolymer (A) comprises an ethylene / α-olefin copolymer (a) portion and a vinyl polymer portion which is a polymer of the vinyl monomer component (m1).
As described later, the ethylene / α-olefin copolymer (a) may be dispersed in water to form an aqueous olefin resin dispersion (p).

  In the graft copolymer (A), it is difficult to specify how the vinyl monomer component (m1) is polymerized in the presence of the ethylene / α-olefin copolymer (a). It is. For example, vinyl polymers obtained by polymerizing the vinyl monomer component (m1) include those bonded to the ethylene / α-olefin copolymer (a) and ethylene / α-olefin copolymer (a). Some are not connected. It is also difficult to specify the molecular weight of the vinyl polymer bonded to the ethylene / α-olefin copolymer (a), the proportion of structural units, and the like. That is, there is a situation (impossible / unpractical situation) that the graft copolymer (A) cannot be directly specified by its structure or characteristics or is almost impractical. Accordingly, in the present invention, the graft copolymer (A) is obtained by polymerizing the vinyl monomer component (m1) in the presence of the ethylene / α-olefin copolymer (a). "Is more appropriate.

  The graft copolymer (A) of the present invention is typically a vinyl monomer component (m1) in an aqueous olefin resin dispersion (p) containing an ethylene / α-olefin copolymer (a). It was obtained by polymerizing.

<Ethylene / α-olefin copolymer (a)>
The ethylene / α-olefin copolymer (a) used for obtaining the graft copolymer (A) is obtained by copolymerizing ethylene and an α-olefin having 3 or more carbon atoms by a known polymerization method. And a copolymer containing an ethylene unit and an α-olefin unit.
The ethylene / α-olefin copolymer (a) may further contain a non-conjugated diene unit.

  Examples of the α-olefin include propylene, 1-butene, 1-pentene, 1-hexene, 1-heptene, 1-octene, 1-decene, 1-undecene, 1-icosene and 1-docosene. These can be used alone or in combination of two or more. From the viewpoint of impact resistance of the obtained molded product, an α-olefin having 3 to 20 carbon atoms is preferable, and propylene is particularly preferable.

  Non-conjugated dienes include dicyclopentadiene, 5-ethylidene-2-norbornene, 1,4-hexadiene, 1,5-hexadiene, 2-methyl-1,5-hexadiene, 1,4-cycloheptadiene, 1, 5-cyclooctadiene etc. are mentioned. These can be used alone or in combination of two or more. Among these non-conjugated dienes, at least one of dicyclopentadiene and 5-ethylidene-2-norbornene is preferable because the resulting molded article has excellent impact resistance and scratch resistance.

  The ethylene unit content of the ethylene / α-olefin copolymer (a) is 45 to 45% when the total of all the structural units constituting the ethylene / α-olefin copolymer (a) is 100% by mass. 80 mass% is preferable and 50-75 mass% is more preferable. When the ethylene unit content is within the above range, the resulting molded article has a further excellent balance of scratch resistance and impact resistance.

  The total content of ethylene units and α-olefin units is preferably 90 to 100% by mass when the total of all the structural units constituting the ethylene / α-olefin copolymer (a) is 100% by mass. 95-99 mass% is more preferable. When the total content of ethylene units and α-olefin units is within the above range, the balance of scratch resistance and impact resistance of the obtained molded product is further improved.

The mass average molecular weight (Mw) of the ethylene / α-olefin copolymer (a) is preferably 30,000 to 350,000, and more preferably 50,000 to 330,000. When the mass average molecular weight (Mw) of the ethylene / α-olefin copolymer (a) is within the above range, the obtained molded article has excellent scratch resistance and impact resistance.
The molecular weight distribution (Mw / number average molecular weight (Mn)) of the ethylene / α-olefin copolymer (a) is preferably 1.0 to 5.0, and more preferably 1.9 to 4.0. When the molecular weight distribution (Mw / Mn) of the ethylene / α-olefin copolymer (a) is within the above range, the impact resistance of the obtained molded article is excellent.
The mass average molecular weight (Mw) and the number average molecular weight (Mn) of the ethylene / α-olefin copolymer (a) are values measured by gel permeation chromatography (GPC) and converted to standard polystyrene.

The volume average particle diameter of the ethylene / α-olefin copolymer (a) is 180 to 550 nm, and preferably 200 to 500 nm.
Here, the volume average particle size in the present invention is a value calculated from a particle size distribution obtained by measuring a volume-based particle size distribution by a dynamic light scattering method using a particle size distribution meter.
When the volume average particle diameter of the ethylene / α-olefin copolymer is less than the lower limit value, the impact resistance of the obtained molded product may be lowered, and when the upper limit value is exceeded, the color developability is lowered. There is.
The average particle diameter of the ethylene / α-olefin copolymer (a) is the average of the graft copolymer (A) or the average of the ethylene / α-olefin copolymer (a) in the thermoplastic resin composition described later. It has been confirmed by image analysis with an electron microscope that the particle diameter is reached.

  The gel content of the ethylene / α-olefin copolymer (a) is 1 to 80% by mass, and more preferably 2 to 75% by mass. It is substantially difficult to obtain an ethylene / α-olefin copolymer (a) having a gel content of less than the lower limit. When the gel content of the ethylene / α-olefin copolymer (a) exceeds the upper limit, the color developability and impact resistance of the resulting molded product may be lowered.

The gel content of the ethylene / α-olefin copolymer (a) is determined by the following measuring method.
A sample [E1] 0.5 g of the ethylene / α-olefin copolymer (a) is immersed in 200 mL of 110 ° C. toluene for 5 hours to obtain a solution. Next, the solution is filtered through a 200 mesh wire net, the residue is dried, and the mass (g) of the dried product [E2] is measured. From the following formula (1), the gel content of the ethylene / α-olefin copolymer (a) is determined.
Gel content (% by mass) = [E2] / [E1] × 100 (1)

  When the ethylene / α-olefin copolymer (a) is contained in the olefin resin aqueous dispersion (p) described later, dilute sulfuric acid is added to the aqueous olefin resin dispersion (p) to produce ethylene / α. -The olefin copolymer (a) is coagulated, and the obtained coagulated powder is washed with water and dried. Let the dried coagulated powder be a sample [E1] of the ethylene / α-olefin copolymer (a).

  The method for producing the ethylene / α-olefin copolymer (a) is not limited. The ethylene / α-olefin copolymer (a) is usually obtained by copolymerizing ethylene and α-olefin or ethylene, α-olefin and non-conjugated diene using a metallocene catalyst or Ziegler-Natta catalyst. Manufactured.

As a metallocene catalyst, a catalyst obtained by combining an organic compound having a cyclopentadienyl skeleton with a transition metal (zirconium, titanium, hafnium, etc.), a metallocene complex in which a halogen atom or the like is coordinated, an organoaluminum compound, an organoboron compound, etc. Is mentioned.
Examples of the Ziegler-Natta catalyst include a catalyst in which a halide of a transition metal (titanium, vanadium, zirconium, hafnium, etc.) is combined with an organic aluminum compound, an organic boron compound, or the like.

  Examples of the polymerization method include a method of copolymerizing ethylene and α-olefin or ethylene, α-olefin and nonconjugated diene in a solvent in the presence of the catalyst.

  Examples of the solvent include hydrocarbon solvents (benzene, toluene, xylene, pentane, hexane, heptane, octane, etc.). A hydrocarbon solvent may be used individually by 1 type, and 2 or more types may be mixed and used for it. Moreover, you may use the raw material alpha olefin as a solvent.

  By changing reaction conditions such as supply amount of ethylene, α-olefin and non-conjugated diene, type and amount of molecular weight regulator such as hydrogen, type and amount of catalyst, reaction temperature and pressure, ethylene and α-olefin The ethylene unit content, mass average molecular weight (Mw), and molecular weight distribution (Mw / Mn) of the copolymer (a) can be adjusted.

  Further, by adjusting the type or amount of the emulsifier, the type or content of the acid-modified olefin polymer, the shearing force applied at the time of kneading, the temperature conditions, etc. Combined (a) can be obtained.

In the production of the graft copolymer (A), the ethylene / α-olefin copolymer (a) may be used as it is or in a state dispersed in an aqueous medium.
The ethylene / α-olefin copolymer (a) preferably has a crosslinked structure. When the ethylene / α-olefin copolymer (a) has a crosslinked structure, the impact resistance of the obtained molded product is further improved.

  In the present specification, an ethylene / α-olefin copolymer (a) dispersed in an aqueous medium is referred to as “olefin resin aqueous dispersion (p)”. The ethylene / α-olefin copolymer (a) having a crosslinked structure is also referred to as “crosslinked ethylene / α-olefin copolymer (ac)”. The ethylene / α-olefin copolymer (a) having no crosslinked structure is also referred to as “uncrosslinked ethylene / α-olefin copolymer (a)”.

<Olefin resin aqueous dispersion (p)>
The aqueous olefin resin dispersion (p) is obtained by dispersing the ethylene / α-olefin copolymer (a) in an aqueous medium.
The aqueous olefin resin dispersion (p) may contain an emulsifier, an acid-modified olefin polymer, and the like as other components.

  Examples of the aqueous medium include water, an organic solvent miscible with water (hereinafter, also referred to as “water-miscible organic solvent”), and a mixture thereof. Examples of the water-miscible organic solvent include alcohols such as methanol, ethanol, n-propanol and isopropanol: ketones such as acetone and methyl ethyl ketone: polyalkylene glycols such as ethylene glycol, diethylene glycol and propylene glycol: polyalkylene glycol Alkyl ethers: Examples include lactams such as N-methyl-2-pyrrolidone.

  As the aqueous medium, it is preferable to use only water or a mixture of water and a water-miscible organic solvent.

  Examples of the emulsifier include known ones, and examples thereof include long-chain alkyl carboxylates, sulfosuccinic acid alkyl ester salts, and alkylbenzene sulfonates.

  The content of the emulsifier in the aqueous olefin resin dispersion (p) can suppress the thermal coloring of the resulting thermoplastic resin composition, and the ethylene / α-olefin copolymer dispersed in the aqueous olefin resin dispersion (p). 1-10 mass parts is preferable with respect to 100 mass parts of ethylene * alpha-olefin copolymers (a) from the point that the particle diameter control of a coalescence (a) is easy.

  Examples of the acid-modified olefin polymer include those obtained by modifying an olefin polymer having a mass average molecular weight of 1,000 to 5,000 (polyethylene, polypropylene, etc.) with a compound having a functional group (such as an unsaturated carboxylic acid compound). It is done. Examples of the unsaturated carboxylic acid compound include acrylic acid, maleic acid, itaconic acid, maleic anhydride, itaconic anhydride, maleic acid monoamide, and the like.

  The content of the acid-modified olefin polymer in the aqueous olefin resin dispersion (p) is preferably 1 to 40 parts by mass with respect to 100 parts by mass of the ethylene / α-olefin copolymer (a). When the addition amount of the acid-modified olefin polymer is within the above range, the balance between scratch resistance and impact resistance of the obtained molded product is further improved.

  The preparation method of the olefin resin aqueous dispersion (p) is not limited. As a method for preparing the aqueous dispersion of olefin resin (p), for example, (M1) the ethylene / α-olefin copolymer (a) is prepared by a known melt-kneading means (kneader, Banbury mixer, multi-screw extruder, etc.). Method of melt-kneading, dispersing by applying mechanical shear force, and adding to aqueous medium: (M2) Ethylene / α-olefin copolymer (a) is added to hydrocarbon solvent (pentane, hexane, heptane, benzene, toluene, For example, a method in which it is dissolved in xylene and the like, added to an aqueous medium and emulsified, and then sufficiently stirred to distill off the hydrocarbon solvent.

  In preparing the aqueous olefin resin dispersion (p), the above-mentioned acid-modified olefin polymer, emulsifier and the like may be added as other components.

The method for adding the acid-modified olefin polymer is not limited. For example, in the method (M1), the ethylene / α-olefin copolymer (a) and the acid-modified olefin polymer are mixed and melt-kneaded, and in the method (M2), the ethylene / α-olefin is mixed. Examples include a method of dissolving the copolymer (a) and the acid-modified olefin polymer in a hydrocarbon solvent.
The mixing method of the ethylene / α-olefin copolymer (a) and the acid-modified olefin polymer is not limited. Examples of the mixing method include a melt kneading method using a kneader, a Banbury mixer, a multi-screw extruder and the like. In this case, the step of mixing the ethylene / α-olefin copolymer (a) and the acid-modified olefin polymer may also serve as a step of melt-kneading the mixture.

  The method for adding the emulsifier is not limited. For example, the method similar to the addition method of an acid-modified olefin polymer is mentioned. Examples of the method (M1) or (M2) include a method of adding an emulsifier to an aqueous medium, and a method of dissolving the emulsifier in a hydrocarbon solvent in the method (M2).

The volume average particle diameter of the ethylene / α-olefin copolymer (a) constituting the aqueous olefin resin dispersion (p) is also 180 to 550 nm, preferably 200 to 500 nm.
When the volume average particle diameter of the ethylene / α-olefin copolymer (a) constituting the aqueous olefin resin dispersion (p) is less than the lower limit, the impact resistance of the resulting molded product may be lowered. If the upper limit is exceeded, the color developability may decrease.

  The average particle diameter of the ethylene / α-olefin copolymer (a) constituting the aqueous olefin resin dispersion (p) is the same as that of the graft copolymer (A) or the ethylene / α in the thermoplastic resin composition described later. It has been confirmed by electron microscope image analysis that the average particle size of the α-olefin copolymer (a) is obtained.

  As a method for controlling the average particle size of the ethylene / α-olefin copolymer (a) dispersed in the aqueous olefin resin dispersion (p), the type or amount of the emulsifier, the type of the acid-modified olefin polymer, Examples thereof include a method of adjusting the content, shearing force applied during kneading, temperature conditions, and the like.

<Crosslinked ethylene / α-olefin copolymer (ac)>
The crosslinked ethylene / α-olefin copolymer (ac) is an olefin in which an uncrosslinked ethylene / α-olefin copolymer (a) or an uncrosslinked ethylene / α-olefin copolymer (a) is dispersed in an aqueous medium. It can be obtained by crosslinking the aqueous resin dispersion (p). When the crosslinked ethylene / α-olefin copolymer (ac) is obtained by crosslinking the olefin resin aqueous dispersion (p), the crosslinked ethylene / α-olefin copolymer (ac) is used as an aqueous dispersion. can get. The aqueous dispersion of the crosslinked ethylene / α-olefin copolymer (ac) may be referred to as “crosslinked olefin resin aqueous dispersion (q)”.

  As a crosslinking treatment method, (M3) a method in which an organic peroxide and, if necessary, a polyfunctional compound are added for treatment: (M4) a method for carrying out a crosslinking treatment by adding a polyfunctional compound : (M5) A method of performing treatment with ionizing radiation, and the like. Among the crosslinking treatment methods, the methods (M3) and (M4) are preferable, and the method (M3) is more preferable because the molded article obtained has good impact resistance and color developability.

  As the method of (M3), specifically, an uncrosslinked ethylene / α-olefin copolymer (a) or an aqueous olefin resin dispersion (p) in which this is dispersed in an aqueous medium, an organic peroxide, The method etc. which add and heat a polyfunctional compound as needed are mentioned.

  For example, an organic peroxide and, if necessary, a polyfunctional compound are added to the uncrosslinked ethylene / α-olefin copolymer (a), melt-kneaded, and pulverized to form a crosslinked ethylene / α-olefin. A powder of copolymer (ac) is obtained. Moreover, when an organic peroxide and, if necessary, a polyfunctional compound are added to the olefin resin aqueous dispersion (p) for treatment, a crosslinked olefin containing a crosslinked ethylene / α-olefin copolymer (ac) is obtained. An aqueous resin dispersion (q) is obtained.

  The heating temperature varies depending on the type of organic peroxide. The heating temperature is preferably −5 ° C. to + 30 ° C., which is the 10-hour half-life temperature of the organic peroxide. The heating time is preferably 3 to 15 hours.

  The organic peroxide is used to form a crosslinked structure in the uncrosslinked ethylene / α-olefin copolymer (a). Examples of the organic peroxide include a peroxy ester compound, a peroxy ketal compound, a dialkyl peroxide compound, and the like. An organic peroxide may be used individually by 1 type, and may be used in combination of 2 or more type. As the organic peroxide, a dialkyl peroxide compound is particularly preferable because the gel content of the crosslinked ethylene / α-olefin copolymer (ac) can be easily adjusted.

  Specific examples of the dialkyl peroxide compound include α, α′-bis (t-butylperoxy) diisopropylbenzene, dicumyl peroxide, 2,5-dimethyl-2,5-bis (t-butylperoxy) hexane, and t-butyl. Examples include cumyl peroxide, di-t-butyl peroxide, 2,5-dimethyl-2,5-bis (t-butylperoxy) hexyne-3 and the like.

  The amount of the organic peroxide added is that the gel content of the crosslinked ethylene / α-olefin copolymer (ac) can be easily adjusted to 1 to 80% by mass, so that the uncrosslinked ethylene / α-olefin copolymer ( a) 5.0 mass parts or less are preferable with respect to 100 mass parts, and 0.1-4.5 mass parts is more preferable.

  The polyfunctional compound is used alone or in combination with an organic peroxide as necessary in order to adjust the gel content of the crosslinked ethylene / α-olefin copolymer (ac). .

  Examples of polyfunctional compounds include divinylbenzene, 1,7-octadiene allyl methacrylate, ethylene glycol dimethacrylate, 1,3-butylene dimethacrylate, tetraethylene glycol diacrylate, triallyl cyanurate, triallyl isocyanurate, penta Examples include erythritol tetraacrylate. A polyfunctional compound may be used individually by 1 type, and may be used in combination of 2 or more type.

  Since the addition amount of the polyfunctional compound is easy to adjust the gel content of the crosslinked ethylene / α-olefin copolymer (ac) to 1 to 80% by mass, an uncrosslinked ethylene / α-olefin copolymer ( a) 10 mass parts or less are preferable with respect to 100 mass parts.

  When the uncrosslinked ethylene / α-olefin copolymer (a) is treated to obtain a crosslinked ethylene / α-olefin copolymer (ac), an acid is added to the uncrosslinked ethylene / α-olefin copolymer (a). A modified olefin polymer may be added.

  As the acid-modified olefin polymer, the same ones as mentioned in the explanation of the aqueous olefin resin dispersion (p) can be used. The amount of the acid-modified olefin polymer added is 100 parts by mass of the uncrosslinked ethylene / α-olefin copolymer (a), similarly to the content of the acid-modified olefin polymer in the aqueous olefin resin dispersion (p). On the other hand, 1-40 mass parts is preferable.

  The method for adding the acid-modified olefin polymer is not limited. The uncrosslinked ethylene / α-olefin copolymer (a) and the acid-modified olefin polymer may be mixed and then treated, or the uncrosslinked ethylene / α-olefin copolymer (a) and the acid-modified You may mix after processing each olefin polymer.

  The mixing method of the uncrosslinked ethylene / α-olefin copolymer (a) and the acid-modified olefin polymer is not limited. Examples of the mixing method include a melt kneading method using a kneader, a Banbury mixer, a multi-screw extruder and the like.

When the olefin resin aqueous dispersion (p) is crosslinked with an organic peroxide, the volume average particle diameter of the crosslinked ethylene / α-olefin copolymer (ac) in the crosslinked olefin resin aqueous dispersion (q) is: It is equivalent to the volume average particle diameter of the uncrosslinked ethylene / α-olefin copolymer (a).
The average particle diameter of the crosslinked ethylene / α-olefin copolymer (ac) constituting the crosslinked olefin resin aqueous dispersion (q) is as it is in the graft copolymer (A) or the thermoplastic resin composition described later. The average particle diameter of the crosslinked ethylene / α-olefin copolymer (ac) has been confirmed by image analysis using an electron microscope.

The gel content of the crosslinked ethylene / α-olefin copolymer (ac) is 1 to 80% by mass, preferably 20 to 30% by mass. It is substantially difficult to obtain a crosslinked ethylene / α-olefin copolymer (ac) having a gel content of less than the lower limit. When the gel content of the crosslinked ethylene / α-olefin copolymer (ac) exceeds the upper limit, the color developability of the resulting molded product may be lowered.
The method for measuring the gel content of the crosslinked ethylene / α-olefin copolymer (ac) is the same as the method for measuring the gel content of the ethylene / α-olefin copolymer (a) described above.

<Vinyl monomer component (m1)>
The vinyl monomer component (m1) used in obtaining the graft copolymer (A) of the present invention is at least one member selected from the group consisting of aromatic vinyl monomers and vinyl cyanide monomers. Contains monomer. The vinyl monomer component (m1) contains a vinyl monomer (other vinyl monomers) other than the aromatic vinyl monomer and the vinyl cyanide monomer, if necessary. May be.

Examples of the aromatic vinyl monomer include styrene, α-methyl styrene, o-, m- or p-methyl styrene, vinyl xylene, pt-butyl styrene, ethyl styrene, etc. Styrene and α-methylstyrene are preferred from the viewpoint of the fluidity of the plastic resin composition, the color developability of the resulting molded product, and the impact resistance. An aromatic vinyl compound may be used individually by 1 type, and may be used in combination of 2 or more type.
60-85 mass% is preferable in 100 mass% of vinyl-type monomer components (m1), and, as for the content rate of an aromatic vinyl compound, 62-80 mass% is more preferable. When the content of the aromatic vinyl compound is within the above range, the color forming property and impact resistance of the obtained molded product are further improved.

Examples of the vinyl cyanide monomer include acrylonitrile and methacrylonitrile. A vinyl cyanide monomer may be used individually by 1 type, and may be used in combination of 2 or more type.
The content of the vinyl cyanide monomer is preferably 15 to 40% by mass and more preferably 20 to 38% by mass in 100% by mass of the vinyl monomer component (m1). When the content of the vinyl cyanide monomer is within the above range, the color forming property and impact resistance of the obtained molded product are further improved.

  Other vinyl monomers include acrylic acid esters (methyl acrylate, ethyl acrylate, propyl acrylate, butyl acrylate, etc.), methacrylic acid esters (methyl methacrylate, ethyl methacrylate, propyl methacrylate, methacrylic acid) Butyl etc.). Another vinyl-type monomer may be used individually by 1 type, and may be used in combination of 2 or more type.

<Method for Producing Graft Copolymer (A)>
The method for producing the graft copolymer (A) is selected from the group consisting of an aromatic vinyl monomer and a vinyl cyanide monomer in the presence of the ethylene / α-olefin copolymer (a). Examples thereof include a method of polymerizing a vinyl monomer component (m1) containing one or more monomers.

  As described above, the ethylene / α-olefin copolymer (a) may be contained in the aqueous olefin resin dispersion (p). When the ethylene / α-olefin copolymer (a) is a crosslinked ethylene / α-olefin copolymer (ac), the crosslinked ethylene / α-olefin copolymer (ac) is a crosslinked olefin resin aqueous dispersion ( It may be included in q).

  The graft copolymer (A) is an ethylene / α-olefin copolymer (a) in the presence of 40 to 80% by mass, and the vinyl monomer component (m1) is 20 to 60% by mass (provided that ethylene / α -The thing obtained by superposing | polymerizing an olefin copolymer (a) and a vinyl-type monomer component (m1) is 100 mass%) is preferable. When the content ratio of the ethylene / α-olefin copolymer in the graft copolymer (A) is 40 to 80% by mass, the impact resistance of the resulting thermoplastic resin composition is further improved.

  The graft ratio of the graft copolymer (A) is preferably 20 to 100% and more preferably 25 to 100% because the impact resistance of the thermoplastic resin composition is more excellent. The method for measuring the graft copolymer (A) is as shown in the Examples section below.

Examples of the polymerization method of the vinyl monomer component (m1) include known polymerization methods (emulsion polymerization method, solution polymerization method, suspension polymerization method, bulk polymerization method, etc.).
As a method for producing the graft copolymer (A) by the emulsion polymerization method, for example, an ethylene / α-olefin copolymer (a) prepared by mixing an organic peroxide with a vinyl monomer component (m1) is used. The method of adding continuously with respect to this aqueous dispersion is mentioned.

The organic peroxide is preferably used as a redox initiator that combines an organic peroxide, a transition metal, and a reducing agent.
In the polymerization, a chain transfer agent, an emulsifier or the like may be used depending on the situation.
As a redox-based initiator, it is not necessary to set the polymerization reaction conditions at a high temperature, avoiding deterioration of the ethylene / α-olefin copolymer (a), etc., and from reducing the impact resistance of the molded product, A combination of an organic peroxide and ferrous sulfate-chelating agent-reducing agent is preferred.
Examples of the organic peroxide include cumene hydroperoxide, diisopropylbenzene hydroperoxide, and t-butyl hydroperoxide.
The redox initiator is more preferably composed of cumene hydroperoxide, ferrous sulfate, sodium pyrophosphate, and fructose.

Examples of chain transfer agents include mercaptans (octyl mercaptan, n- or t-dodecyl mercaptan, n-hexadecyl mercaptan, n- or t-tetradecyl mercaptan, etc.), allyl compounds (allylsulfonic acid, methallylsulfonic acid, these Sodium salts, etc.), α-methylstyrene dimers, and the like, and mercaptans are preferred from the viewpoint of easy adjustment of the molecular weight. A chain transfer agent may be used individually by 1 type, and may be used in combination of 2 or more type.
The method for adding the chain transfer agent may be any of batch, split, and continuous.
The addition amount of the chain transfer agent is preferably 2.0 parts by mass or less with respect to 100 parts by mass of the vinyl monomer component (m1).

Examples of the emulsifier include anionic surfactants, nonionic surfactants, and amphoteric surfactants.
Examples of the anionic surfactants include higher alcohol sulfates, alkylbenzene sulfonates, fatty acid sulfonates, phosphate salts, fatty acid salts, and amino acid derivative salts.
Examples of nonionic surfactants include ordinary polyethylene glycol alkyl ester types, alkyl ether types, and alkyl phenyl ether types.
Examples of the amphoteric surfactant include those having a carboxylate salt, sulfate ester salt, sulfonate salt, phosphate ester salt and the like in the anion portion and amine salts and quaternary ammonium salts in the cation portion.

  The amount of the emulsifier added is preferably 10 parts by mass or less with respect to 100 parts by mass of the vinyl monomer component (m1).

The graft copolymer (A) obtained by the emulsion polymerization method is in a state of being dispersed in an aqueous medium.
As a method for recovering the graft copolymer (A) from the aqueous dispersion containing the graft copolymer (A), for example, a precipitation agent is added to the aqueous dispersion, heated and stirred, and then the precipitation agent is separated. And a precipitation method in which the precipitated graft copolymer (A) is washed with water, dehydrated and dried.
Examples of the precipitating agent include aqueous solutions of sulfuric acid, acetic acid, calcium chloride, magnesium sulfate, and the like. A precipitation agent may be used individually by 1 type, and may be used in combination of 2 or more type.
An antioxidant may be added to the aqueous dispersion containing the graft copolymer (A) as necessary.

[Copolymer (B)]
The copolymer (B) of the present invention is a copolymer obtained by polymerizing an aromatic vinyl monomer, a (meth) acrylic acid ester monomer, and an unsaturated dicarboxylic acid anhydride monomer ( B), a total of 100 aromatic vinyl monomer units, (meth) acrylic acid ester monomer units, and unsaturated dicarboxylic acid anhydride monomer units contained in the copolymer (B). The content of the aromatic vinyl monomer unit is 40 to 68% by mass with respect to mass%, and the unsaturated dicarboxylic acid anhydride monomer unit contained in the copolymer (B) is maleic anhydride. It is a unit.

  Examples of the aromatic vinyl monomer unit contained in the copolymer (B) of the present invention include styrene, o-methylstyrene, m-methylstyrene, p-methylstyrene, 2,4-dimethylstyrene, ethylstyrene, Examples include units derived from styrene monomers such as p-tert-butylstyrene, α-methylstyrene, and α-methyl-p-methylstyrene. Of these, styrene units are preferred. These aromatic vinyl monomer units may be one type or a combination of two or more types.

  (Meth) acrylic acid ester monomer units include methyl methacrylate monomers such as methyl methacrylate, ethyl methacrylate, n-butyl methacrylate, 2-ethylhexyl methacrylate, dicyclopentanyl methacrylate, and isobornyl methacrylate. And units derived from each acrylate monomer such as methyl acrylate, ethyl acrylate, n-butyl acrylate, 2-methylhexyl acrylate, 2-ethylhexyl acrylate, decyl acrylate, and the like. Among these, a methyl methacrylate unit is preferable. These (meth) acrylic acid ester-based monomer units may be one kind or a combination of two or more kinds.

  Examples of the unsaturated dicarboxylic acid anhydride monomer unit include units derived from respective anhydride monomers such as maleic acid anhydride, itaconic acid anhydride, citraconic acid anhydride, and aconitic acid anhydride. These unsaturated dicarboxylic acid anhydride monomers may be used alone or in combination of two or more. Among these, maleic anhydride units are preferable.

  The copolymer (B) of the present invention contains aromatic vinyl in a total of 100% by mass of aromatic vinyl monomer units, (meth) acrylic acid ester units and unsaturated dicarboxylic acid anhydride monomer units. 40 to 68% by mass of monomer units, preferably 20 to 30% by mass of (meth) acrylic acid ester monomer units, and 8 to 20% by mass of unsaturated dicarboxylic acid anhydride monomer units. . More preferably, the aromatic vinyl monomer unit is 50 to 68% by mass, the (meth) acrylic acid ester monomer unit is 22 to 28% by mass, and the unsaturated dicarboxylic acid anhydride monomer unit is 10 to 18% by mass. is there.

  When the aromatic vinyl monomer unit is 68% by mass or less, the effect of imparting heat resistance to the thermoplastic resin composition is improved. When the (meth) acrylic acid ester monomer unit is 30% by mass or less, the thermal stability is improved and a molded article having a good appearance can be obtained. When the unsaturated dicarboxylic acid anhydride monomer unit is 20% by mass or less, the thermal stability is improved and a molded article having a good appearance can be obtained. On the other hand, if the aromatic vinyl monomer unit is 40% by mass or more, the heat resistance imparting effect of the thermoplastic resin composition is improved. When the (meth) acrylic acid ester monomer unit is 20% by mass or more, the thermal stability is improved, and a molded product having a good appearance can be obtained. If the unsaturated dicarboxylic acid anhydride monomer unit is 8% by mass or more, the thermal stability is improved, and a molded product having a good appearance can be obtained.

  The copolymer (B) of the present invention can be copolymerized other than aromatic vinyl monomer units, (meth) acrylic acid ester monomer units, and unsaturated dicarboxylic anhydride monomer units. Other vinyl monomer units may be included in the copolymer as long as the effects of the invention are not impaired. In that case, the content of the other vinyl monomer units that can be copolymerized is 100% of copolymer (B). Preferably in the mass%, it is 5 mass% or less. Examples of other copolymerizable vinyl monomer units include units derived from unsaturated nitrile monomers such as acrylonitrile and methacrylonitrile, and vinyl carboxylic acid monomers such as acrylic acid and methacrylic acid. Two or more types of copolymerizable vinyl monomer units may be used.

The copolymer (B) of the present invention preferably has a mass average molecular weight (Mw) of 100,000 to 200,000, and more preferably a mass average molecular weight (Mw) of 120,000 to 180,000. If the mass average molecular weight (Mw) is too large, the moldability of the thermoplastic resin composition and the appearance of the resulting molded product may be inferior. If the mass average molecular weight (Mw) is too small, the moldability and the molded product may be reduced. May be inferior in strength.
Here, the mass average molecular weight (Mw) of the copolymer (B) is a value in terms of polystyrene by gel permeation chromatography (GPC).

The manufacturing method of the copolymer (B) of this invention is demonstrated below.
There is no particular limitation on the polymerization mode for producing the copolymer (B) of the present invention, and it can be produced by a known method such as solution polymerization or bulk polymerization, but solution polymerization is more preferred. The solvent used in the solution polymerization is preferably non-polymerizable from the viewpoint that a by-product is difficult to produce and that there are few adverse effects. The type of solvent is not particularly limited. For example, ketones such as acetone, methyl ethyl ketone, methyl isobutyl ketone and acetophenone, ethers such as tetrahydrofuran and 1,4-dioxane, toluene, ethylbenzene, xylene and chlorobenzene Aromatic hydrocarbons, etc. are mentioned, but methyl ethyl ketone and methyl isobutyl ketone are preferred from the viewpoint of the solubility of the monomer and copolymer and the ease of solvent recovery.

  10-100 mass parts is preferable with respect to 100 mass parts of copolymers (B) obtained, and, as for the addition amount of a solvent, More preferably, it is 30-80 mass parts. If the addition amount of the solvent is 10 parts by mass or more, it is suitable for controlling the reaction rate and the viscosity of the polymerization solution, and if it is 100 parts by mass or less, it is suitable for obtaining a desired mass average molecular weight (Mw). is there.

The polymerization method is not particularly limited, but is preferably a radical polymerization method from the viewpoint that it can be produced with high productivity by a simple process.
The polymerization initiator is not particularly limited. For example, dibenzoyl peroxide, t-butyl peroxybenzoate, 1,1-bis (t-butylperoxy) -2-methylcyclohexane, t-butyl peroxy Known organic compounds such as isopropyl monocarbonate, t-butylperoxy-2-ethylhexanoate, t-butylperoxyacetate, dicumyl peroxide, ethyl-3,3-di- (t-butylperoxy) butyrate Known azo compounds such as peroxides, azobisisobutyronitrile, azobiscyclohexanecarbonitrile, azobismethylpropionitrile, azobismethylbutyronitrile, and the like can be used. Two or more of these polymerization initiators can be used in combination. Among these, it is preferable to use an organic peroxide having a 10-hour half-life temperature of 70 to 110 ° C.

  In the polymerization of the copolymer (B), it is preferable to perform polymerization so that the copolymer composition distribution becomes small. That is, since the aromatic vinyl monomer and the unsaturated dicarboxylic acid anhydride monomer have strong alternating copolymerization properties, the aromatic vinyl monomer and the (meth) acrylic acid ester monomer A method of continuously adding unsaturated dicarboxylic acid anhydride monomer so as to correspond to the polymerization rate is preferred. The control of the polymerization rate can be adjusted by the polymerization temperature, the polymerization time, and the addition amount of the polymerization initiator. It is preferable to continuously add a polymerization initiator because the polymerization rate can be more easily controlled. By reducing the copolymer composition distribution, it is preferable because a copolymer (B) and a molded product having an excellent balance between heat resistance and strength can be obtained.

  Moreover, in order to make the mass average molecular weight (Mw) of the copolymer (B) obtained into a preferable range of 100,000 to 200,000, in addition to the adjustment of the polymerization temperature, the polymerization time, and the addition amount of the polymerization initiator. And a method of adjusting the addition amount of the solvent and the addition amount of the chain transfer agent. Although it does not specifically limit as a chain transfer agent, For example, using well-known chain transfer agents, such as n-dodecyl mercaptan, t-dodecyl mercaptan, and 2, 4- diphenyl-4-methyl- 1-pentene. Can do.

  There is no limitation in particular about the method of collect | recovering the copolymer (B) of this invention from a polymerization reaction liquid, A well-known devolatilization technique can be used. For example, a method in which a polymerization reaction solution is continuously fed to a twin-screw devolatilizing extruder using a gear pump to devolatilize a polymerization solvent, unreacted monomers, and the like. The devolatilizing component including the polymerization solvent, unreacted monomer, etc. is condensed and recovered using a condenser, etc., and the polymerization solvent can be reused by purifying the condensate in a distillation tower. .

[Content Ratio of Graft Copolymer (A) and Copolymer (B)]
The thermoplastic resin composition of the present invention comprises 28 to 48 mass of the graft copolymer (A) with respect to 100 mass% in total of the graft copolymer (A) of the present invention and the copolymer (B) of the present invention. %, And the copolymer (B) is contained in an amount of 52 to 72% by mass. By including the graft copolymer (A) and the copolymer (B) within this limited range, a molded product having excellent fluidity, heat resistance, impact resistance, color development, and scratch resistance is provided. can do.
The thermoplastic resin composition of the present invention comprises 30 to 46 mass% of the graft copolymer (A) with respect to 100 mass% in total of the graft copolymer (A) of the present invention and the copolymer (B) of the present invention. %, And the copolymer (B) is preferably contained in an amount of 54 to 70% by mass.
The thermoplastic resin composition of the present invention may contain only one kind of the graft copolymer (A) of the present invention, and the composition and physical properties of the ethylene / α-olefin copolymer (a). Two or more different ones such as copolymerization components may be included. Similarly, the copolymer (B) of the present invention may contain only one type, or may contain two or more types.

[Other thermoplastic resins]
The thermoplastic resin composition of the present invention may contain a thermoplastic resin other than the graft copolymer (A) and the copolymer (B) of the present invention.
Examples of other thermoplastic resins include polycarbonate, polybutylene terephthalate, polyethylene terephthalate, polyvinyl chloride, polystyrene, polyacetal, modified polyphenylene ether, ethylene-vinyl acetate copolymer, polyarylate, liquid crystal polyester, polyethylene, polypropylene, and fluorine. Examples thereof include resins and polyamides. Another thermoplastic resin may be used individually by 1 type, and may use 2 or more types together.

  When the thermoplastic resin composition of the present invention contains other thermoplastic resin, in order to effectively obtain the effect of containing the graft copolymer (A) and the copolymer (B) of the present invention, Others in 100% by mass of all resin components in the thermoplastic resin composition of the present invention (usually, the total of the graft copolymer (A) and copolymer (B) of the present invention and other thermoplastic resins) The thermoplastic resin is preferably contained in an amount of 80% by mass or less, particularly 50% by mass or less.

[Various additives]
The thermoplastic resin composition of the present invention may contain various additives as long as the object of the present invention is not impaired. Examples of various additives include antioxidants, lubricants, processing aids, pigments, dyes, fillers, silicone oils, paraffin oils, and the like. These additives may be used individually by 1 type, and may use 2 or more types together.

〔Molding〕
The molded article of the present invention can be obtained by molding the thermoplastic resin composition of the present invention by a known molding method.
Examples of the molding method include injection molding, press molding, extrusion molding, vacuum molding, and blow molding.
The use of the molded article includes vehicle interior / exterior parts, office equipment, home appliances, building materials, etc., and vehicle interior / exterior parts are preferable.
In particular, the thermoplastic resin composition of the present invention is effective for use in vehicle interior / exterior parts because of excellent fluidity and excellent heat resistance, impact resistance, color development, and scratch resistance of the resulting molded product. .

Hereinafter, an example is shown concretely. However, the present invention is not limited to these examples.
In the following, “%” means “mass%” and “part” means “part by mass”.

[Measurement and evaluation method]
Various measurements and evaluation methods in the following examples and comparative examples are as follows.

<Mass average molecular weight (Mw), molecular weight distribution (Mw / Mn)>
Using GPC (GPC: “GPC / V2000” manufactured by Waters, column: “Shodex AT-G + AT-806MS” manufactured by Showa Denko KK) and using o-dichlorobenzene (145 ° C.) as a solvent, a mass average in terms of polystyrene Molecular weight (Mw) and number average molecular weight (Mn) were measured, and molecular weight distribution (Mw / Mn) was calculated.

<Acid value>
The acid value was measured according to JIS K 2501.

<Volume average particle diameter>
The volume average particle diameter (MV) was measured using a micro track (“Nano Track 150” manufactured by Nikkiso Co., Ltd., dynamic light scattering method) using pure water as a measurement solvent.

<Gel content>
A dispersion containing ethylene / α-olefin copolymer (a) (olefin resin aqueous dispersion (p) or crosslinked olefin resin aqueous dispersion (q)) is added with diluted sulfuric acid to produce ethylene / α-olefin copolymer. The coalescence (a) was solidified. The solidified powder thus obtained was washed with water and dried. 0.5 g of the dried coagulated powder sample [E1] was immersed in 200 mL of 110 ° C. toluene for 5 hours to obtain a solution. Next, the solution was filtered through a 200 mesh wire net, the residue was dried, and the mass of the dried product [E2] was measured. From the following formula (1), the gel content of the ethylene / α-olefin copolymer (a) was determined.
Gel content (mass%)
= Dry substance amount [E2] (g) / coagulated powder sample mass [E1] (g) × 100 (1)

<Graft ratio>
1 g of the graft copolymer (A) is added to 80 mL of acetone and heated to reflux at 65 to 70 ° C. for 3 hours. The resulting suspension acetone solution is centrifuged (“CR21E” manufactured by Hitachi Koki Co., Ltd.). The mixture was centrifuged at 14,000 rpm for 30 minutes to separate a precipitation component (acetone insoluble component) and an acetone solution (acetone soluble component). And the precipitation component (acetone insoluble component) was dried, the mass (Y (g)) was measured, and the graft ratio was computed from following formula (2). In Formula (2), Y is the mass (g) of the acetone-insoluble component of the graft copolymer (A), and X is the total mass (g) of the graft copolymer (A) used to determine Y. The rubber fraction is the solid content of the ethylene / α-olefin copolymer (a) in the graft copolymer (A).
Graft rate (%) = {(Y-X × rubber fraction) / X × rubber fraction} × 100 (2)

<Melting and kneading>
Graft copolymer (A) and copolymer (B) were mixed, and 0.8 parts of carbon black was mixed with 100 parts in total of graft copolymer (A) and copolymer (B). The thermoplastic resin composition was colored and melt kneaded at a cylinder temperature of 200 to 260 ° C. and a vacuum of 93.325 kPa using a twin screw extruder with a 28 mmφ vacuum vent (“TEX-28V” manufactured by Nippon Steel Works, Ltd.). Got. Further, after melt-kneading, pelletization was performed using a pelletizer (“SH type pelletizer” manufactured by Souken Co., Ltd.).

<Molding of molded product for physical property evaluation (Ma1)>
The thermoplastic resin composition was formed into a molded product (Ma1) of 100 × 100 mm (thickness 3 mm) by injection molding.

<Molding of molded product for physical property evaluation (Ma2)>
The thermoplastic resin composition was formed into a molded product (Ma2) having a length of 80 mm, a width of 10 mm, and a thickness of 4 mm by injection molding.

<Fluidity>
For the thermoplastic resin composition, the melt volume rate (MVR) was measured under the condition of 230 ° C. in accordance with the ISO 1133 standard.

<Heat resistance>
With respect to the molded product (Ma1), the deflection temperature under load (° C.) was measured by the flatwise method in accordance with the ISO test method 75 standard, 1.83 MPa, 4 mm.

<Impact resistance>
The molded product (Ma2) was subjected to a Charpy impact test (notched) at 23 ° C. in accordance with ISO 179 standard, and the Charpy impact strength was measured.

<Color development>
For the molded product (Ma1), the lightness L ^* was measured by the SCE method using a spectrocolorimeter (“CM-3500d” manufactured by Konica Minolta Optips). The L ^* measured in this way is referred to as “L ^* (ma)”. The lower L ^* , the more black and the better the color developability.

<Scratch resistance>
As shown in FIG. 1, a rod-like jig 10 having a tip 11 formed in a hemispherical shape was prepared, and a car wash towel (Joiful Car Wash Towel 3p) 12 was placed on the tip 11. The tip part 11 covered with the car wash towel 12 is brought into contact with the surface of the molded product (Ma1) 13 so that the rod-shaped jig 10 is at a right angle, and the tip part 11 is brought into contact with the surface of the molded product (Ma1) 13. Were slid in the horizontal direction (arrow direction in the figure) and reciprocated 1000 times. At that time, the applied load was 2 kg. After reciprocating 1000 times, the lightness L ^* of the surface of the molded product (Mc) with scratches was measured by a SCE method using a spectrocolorimeter. The L ^* measured in this way is referred to as “L ^* (mc)”.
(Determination of scratch resistance)
A determination index ΔL ^* of the degree of conspicuousness of scratches on the molded product (Mc) was calculated from the following formula (3). As the absolute value of ΔL ^* (mc−ma) is larger, scratches are more conspicuous.
ΔL ^* (mc−ma) = L ^* (mc) −L ^* (ma) (3)

[Production of Graft Copolymer (A)]
<Manufacture of olefin resin aqueous dispersion (p-1)>
Uncrosslinked ethylene / α-olefin copolymer (a-1) (“DORDEL (Nodel) IP 4725P” manufactured by The Dow Chemical Company, Inc., ethylene / propylene / diene copolymer, ethylene unit content: 70) 100 parts by weight) maleic anhydride-modified polyethylene (“Mitsui High Wax 2203A” manufactured by Mitsui Chemicals, Inc., mass average molecular weight: 2,700, acid value: 30 mg / g) as an acid-modified olefin polymer, 6 parts of potassium oleate was mixed as an anionic emulsifier.
This mixture is supplied at 4 kg / h from a hopper of a twin screw extruder (Ikegai “PCM30”, L / D = 40), and water is supplied from a supply port provided in a vent portion of the twin screw extruder. While continuously supplying an aqueous solution obtained by mixing 0.6 part of potassium oxide and 3.9 parts of ion exchange water, the mixture was heated to 220 ° C., melt-kneaded and extruded. The melt-kneaded product was continuously supplied to a cooling device attached to the tip of the twin screw extruder and cooled to 90 ° C. The solid discharged from the tip of the twin screw extruder is poured into warm water at 80 ° C., continuously dispersed, diluted to a solid content concentration of about 40% by mass, and an aqueous olefin resin dispersion (p -1) was obtained. Table 1 shows the gel content and volume average particle diameter of the uncrosslinked ethylene / α-olefin copolymer (a-1) dispersed in the aqueous olefin resin dispersion (p-1).

<Preparation of aqueous olefin resin dispersions (p-2) to (p-5)>
As shown in Table 1, the aqueous olefin resin dispersion was the same as the aqueous olefin resin dispersion (p-1) except that the number of added parts of potassium hydroxide during emulsification and the number of added parts of ion exchange water were changed. (P-2) to (p-5) were obtained.
Table 1 shows the gel content and volume average particle diameter of the uncrosslinked ethylene / α-olefin copolymer (a-1) dispersed in each of the aqueous dispersions of olefin resin (p-2) to (p-5). Shown in

<Production of cross-linked olefin resin aqueous dispersion (q)>
Ion exchange water was added to the aqueous olefin resin dispersion (p-1) (100 parts as the solid content of the uncrosslinked ethylene / α-olefin copolymer (a-1)) so that the solid content concentration was 30%. Then, 1 part of t-butylcumyl peroxide as an organic peroxide and 1 part of divinylbenzene as a polyfunctional compound were added and reacted at 130 ° C. for 5 hours. As a result, the uncrosslinked ethylene / α-olefin copolymer (a-1) is crosslinked to form a crosslinked olefin resin aqueous dispersion (q-1) containing the crosslinked ethylene / α-olefin copolymer (ac-1). Was prepared. Table 2 shows the gel content and volume average particle diameter of the crosslinked ethylene / α-olefin copolymer (ac-1) contained in the crosslinked olefin resin aqueous dispersion (q-1).

<Production of cross-linked olefin resin aqueous dispersions (q-2) to (q-8)>
As shown in Table 2, the cross-linked olefin was dispersed in the same manner as the cross-linked olefin resin aqueous dispersion (q-1) except that the type of olefin resin aqueous dispersion (p) and the amount of t-butylcumyl peroxide added were changed. Aqueous dispersions of resin aqueous dispersions (q-2) to (q-8) were obtained. The gel content and volume average particle diameter of the crosslinked ethylene / α-olefin copolymers (ac-2) to (ac-8) contained in the aqueous crosslinked olefin resin dispersions (q-2) to (q-8) It shows in Table 2.
In addition, the addition amount (part) of the aqueous olefin resin dispersion (p) shown in Table 2 is the solid content.

<Production of graft copolymer (A-1)>
An aqueous crosslinked olefin resin dispersion (q-1) (70 parts as a solid content of the crosslinked ethylene / α-olefin copolymer (ac-1)) is placed in a stainless polymerization tank equipped with a stirrer, and the aqueous crosslinked olefin resin dispersion is obtained. Ion exchange water is added to (q-1) so that the solid content concentration is 30%, and 0.006 part of ferrous sulfate, 0.3 part of sodium pyrophosphate and 0.35 part of fructose are charged, and the temperature is set to 80. C. To the polymerization tank, 22.5 parts of styrene, 7.5 parts of acrylonitrile and 0.6 part of cumene hydroperoxide were continuously added for 150 minutes, and the polymerization temperature was kept at 80 ° C. to carry out emulsion polymerization. This obtained the aqueous dispersion containing the graft copolymer (A-1) with an average particle diameter of 150 nm. An antioxidant is added to the aqueous dispersion containing the graft copolymer (A-1), and sulfuric acid is added to precipitate a solid, followed by washing, dehydration, and drying steps, and then the powdered graft copolymer is obtained. (A-1) was obtained.

  When the graft ratio of the graft copolymer (A-1) was measured, it was 29%. Moreover, it was 150 nm when the average particle diameter of the bridge | crosslinking ethylene * alpha-olefin copolymer (ac-1) in a thermoplastic resin composition was confirmed with the electron microscope.

<Production of Graft Copolymers (A-2) to (A-8)>
As shown in Table 3, the graft copolymers (A-2) to (A-) were the same as the graft copolymer (A-1) except that the type of the crosslinked olefin resin aqueous dispersion (q) was changed. 8) was obtained. Table 3 shows the graft ratios of the graft copolymers (A-2) to (A-8).

<Production of graft copolymer (A-9)>
The graft copolymer (A-1) was the same as the graft copolymer (A-1) except that the aqueous olefin resin dispersion (p-3) was used instead of the crosslinked aqueous olefin resin dispersion (q-1). -9) was obtained. Table 3 shows the graft ratio of the graft copolymer (A-9).

[Copolymer (B)]
<Copolymer (B-1)>
As the copolymer (B-1), Density Co., Ltd. Resphi R-100 (65% by mass of styrene units, 25% by mass of methyl methacrylate units, 11% by mass of maleic anhydride units) was used.

<Copolymer (B-2)>
As a copolymer (B-2), Density Co., Ltd. Regisfi R-200 (styrene unit 58 mass%, methyl methacrylate unit 26 mass%, maleic anhydride unit 17 mass%) was used.

<Copolymer (B-3)>
As the copolymer (B-3), Resphi R-310 (Styrene unit 71 mass%, methyl methacrylate unit 10 mass%, maleic anhydride unit 19 mass%) manufactured by Denka Co., Ltd. was used.

<Production Example 4: Production of copolymer (B-4)>
20% maleic anhydride solution dissolved in methyl isobutyl ketone so that maleic anhydride has a concentration of 20% and methyl isobutyl so that t-butylperoxy-2-ethylhexanoate is 2% by mass. A 2% t-butylperoxy-2-ethylhexanoate solution diluted with ketone was prepared in advance and used for polymerization.
A 120 liter autoclave equipped with a stirrer was charged with 8 kg of 20% maleic anhydride solution, 0.8 kg of styrene, 17.6 kg of methyl methacrylate and 30 g of t-dodecyl mercaptan, and the gas phase was replaced with nitrogen gas. Then, the temperature was raised to 88 ° C. over 40 minutes with stirring. While maintaining 88 ° C. after the temperature rise, a 20% maleic anhydride solution was added at a rate of 2.5 kg / hour and a 2% t-butylperoxy-2-ethylhexanoate solution was added at a rate of 250 g / hour, respectively. The addition continued continuously over 6 hours. Thereafter, the addition of the 2% t-butylperoxy-2-ethylhexanoate solution was stopped, and 10 g of t-butylperoxyisopropyl monocarbonate was added. The 20% maleic anhydride solution was heated to 120 ° C. over 2 hours at a temperature increase rate of 16 ° C./hour while maintaining the addition rate of 2.5 kg / hour. The addition of the 20% maleic anhydride solution was stopped when the addition amount reached 20 kg. After the temperature increase, the polymerization was terminated by maintaining 120 ° C. for 1 hour. The polymerization solution was devolatilized from methyl isobutyl ketone and a small amount of unreacted monomer using a known method to obtain a pellet-shaped copolymer (B-4). When the composition of the obtained copolymer (B-4) was analyzed by ¹³ C-NMR method, it was 24% by mass of styrene units, 63% by mass of methyl methacrylate units, and 13% by mass of maleic anhydride units. .

<Production Example 5: Production of copolymer (B-5)>
In a pressure-resistant reaction vessel, 150 parts of distilled water, 20 parts of N-phenylmaleimide, 50 parts of styrene and 30 parts of methyl methacrylate, 0.2 part of 2,2′-azobis (isobutyronitrile), n-octyl Mercaptan (0.25 part) and polyvinyl alcohol (0.7 part) were charged, the internal temperature was raised to 75 ° C., and the reaction was performed for 3 hours. Then, it heated up to 90 degreeC and reaction was completed by hold | maintaining for 60 minutes. The content was washed with a centrifugal dehydrator, dehydrated repeatedly, and dried to obtain a copolymer (B-5).

[Example 1]
Graft copolymer (A-2) 36 parts, copolymer (B-1) 64 parts, carbon black 0.8 parts were mixed and a 28 mmφ vacuum vented twin screw extruder (manufactured by Nippon Steel Works, Ltd. “ TEX-28V ") was melt kneaded at a cylinder temperature of 200 to 260 ° C and a vacuum of 93.325 kPa to obtain a thermoplastic resin composition.
The thermoplastic resin composition was pelletized and various molded products were molded to evaluate fluidity, impact resistance, color development, heat resistance, and scratch resistance. The results are shown in Table 4.

[Examples 2 to 9]
A thermoplastic resin composition was prepared in the same manner as in Example 1 except that the formulation was changed to the formulation shown in Table 4.
The thermoplastic resin composition was pelletized, and various molded products were molded to evaluate fluidity, impact resistance, color development, heat resistance, and scratch resistance. The results are shown in Table 4.

[Comparative Examples 1 to 10]
A thermoplastic resin composition was prepared in the same manner as in Example 1 except that the formulation was changed to the formulation shown in Table 5.
The thermoplastic resin composition was pelletized, and various molded products were molded to evaluate fluidity, impact resistance, color development, heat resistance, and scratch resistance. The results are shown in Table 5.

The thermoplastic resin compositions of Examples 1 to 9 were excellent in fluidity, and the obtained molded articles were excellent in fluidity, impact resistance, color development, heat resistance, and scratch resistance.
Therefore, when the thermoplastic resin composition of the present invention is used, a molded product excellent in fluidity, impact resistance, color development, heat resistance, and scratch resistance can be obtained, and vehicle interior / exterior parts, office equipment, home appliances, building materials are obtained. It can be seen that the present invention can be applied to such uses.
On the other hand, from the results of Comparative Examples 1 to 10, any one other than the present invention was insufficient in fluidity, impact resistance, color development, heat resistance, and scratch resistance.

  Molded articles using the thermoplastic resin composition of the present invention are useful as vehicle interior / exterior parts, office equipment, home appliances, building materials and the like.

10 Jig 11 Tip 12 Car Wash Towel 13 Molded Product (Ma1)

Claims (5)

The following graft copolymer (A) and copolymer (B) are contained, and the graft copolymer (A) and the copolymer (B) are 100% by mass in total with respect to the graft copolymer (A). A thermoplastic resin composition having a content of A) of 28 to 48% by mass and a copolymer (B) of 52 to 72% by mass.
Graft copolymer (A): In the presence of ethylene / α-olefin copolymer (a), one or more monomers selected from the group consisting of aromatic vinyl monomers and vinyl cyanide monomers A graft copolymer obtained by polymerizing a vinyl monomer component (m1) containing a monomer;
The volume average particle diameter of the ethylene / α-olefin copolymer (a) constituting the graft copolymer (A) is 180 nm to 550 nm, and the gel content measured by the following measuring method is 1 to 80% by mass. Graft copolymer (A)
<Measurement method of gel content>
A sample [E1] 0.5 g of the ethylene / α-olefin copolymer (a) is immersed in 200 mL of 110 ° C. toluene for 5 hours to obtain a solution. Next, the solution is filtered through a 200 mesh wire net, the residue is dried, and the mass (g) of the dried product [E2] is measured. From the following formula (1), the gel content of the ethylene / α-olefin copolymer (a) is determined.
Gel content (% by mass) = [E2] / [E1] × 100 (1)
Copolymer (B): a copolymer obtained by polymerizing an aromatic vinyl monomer, a (meth) acrylic acid ester monomer, and an unsaturated dicarboxylic acid anhydride monomer,
With respect to a total of 100% by mass of the aromatic vinyl monomer unit, the (meth) acrylic acid ester monomer, and the unsaturated dicarboxylic acid anhydride monomer unit contained in the copolymer (B), Copolymer (B) having an aromatic vinyl monomer unit content of 40 to 68% by mass The ethylene unit content of the ethylene / α-olefin copolymer (a) is 45 to 80% by mass, and the total content rate of the ethylene unit and the α-olefin unit is 90 to 100% by mass,
The content of the aromatic vinyl monomer in 100% by mass of the vinyl monomer component (m1) is 60 to 80% by mass, and the content of the vinyl cyanide monomer is 15 to 40% by mass. Yes,
The graft copolymer (A) is obtained by polymerizing 20 to 60% by mass of the vinyl monomer component (m1) in the presence of 40 to 80% by mass of the ethylene / α-olefin copolymer (a). The heat according to claim 1, wherein the heat is obtained (provided that the total of the ethylene / α-olefin copolymer (a) and the vinyl monomer component (m1) is 100% by mass) and the graft ratio is 20 to 100%. Plastic resin composition.   The thermoplastic resin composition according to claim 1 or 2, wherein the ethylene / α-olefin copolymer (a) is a cross-linked ethylene / α-olefin copolymer (ac).   With respect to a total of 100% by mass of the aromatic vinyl monomer unit, the (meth) acrylic acid ester monomer unit, and the unsaturated dicarboxylic acid anhydride monomer unit contained in the copolymer (B). The content of aromatic vinyl monomer units is 40 to 68% by mass, the content of (meth) acrylic acid ester monomer units is 20 to 30% by mass, unsaturated dicarboxylic anhydride monomer units. The thermoplastic resin composition according to any one of claims 1 to 3, wherein the content of is 8 to 20% by mass, and the weight average molecular weight (Mw) of the copolymer (B) is 100,000 to 200,000. object.   A molded product obtained by molding the thermoplastic resin composition according to any one of claims 1 to 4.

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