JP2013227501A - Inorganic filler-containing polyolefin resin composition - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a polyolefin resin composition excellent in dispersibility of an inorganic filler, and a molded product made by molding the resin composition and excellent in mechanical and thermal properties.SOLUTION: An inorganic filler-containing polyolefin resin composition contains a dispersant (A) for an inorganic fiber, containing a copolymer (X) having a polyolefin (a) and an unsaturated (poly)carboxylic acid (anhydride) (b) as constituting units, and having an acid value of 50 to 250 mgKOH/g, a polyolefin resin (B), and the inorganic filler (C). A molded product is made by molding the composition.

Description

  The present invention relates to an inorganic filler-containing polyolefin resin composition. More specifically, the present invention relates to a resin composition that gives a molded article having excellent mechanical strength, in which an inorganic filler is well dispersed in a polyolefin resin.

In order to improve the mechanical and thermal properties of the polyolefin resin, an inorganic filler is mixed with the resin. However, since the polyolefin resin and the inorganic filler have low affinity, there are problems in moldability, mechanical strength, etc., and various improvement measures have been proposed.
Examples thereof include a method of adding a silane-modified diene-olefin copolymer (see, for example, Patent Document 1) and a method of adding an acrylic ester copolymer having a high affinity for an inorganic filler (see, for example, Patent Document 2).

Japanese Patent Laid-Open No. 5-125233 JP 2003-3016 A

However, in the method of adding a silane-modified diene-olefin copolymer, since the affinity with the inorganic filler is not yet sufficient, there is a problem that the mechanical properties of the molded product are inferior, and an acrylic ester copolymer is added. Although the method has a high affinity with inorganic fillers, there is a problem that the mechanical strength of the molded product is inferior due to insufficient affinity with the polyolefin resin, and improvement has been eagerly desired.
An object of the present invention is to provide a polyolefin resin composition excellent in the dispersibility of the inorganic filler in the composition, and a molded product excellent in mechanical and thermal properties formed by molding the resin.

  The inventor of the present invention has arrived at the present invention as a result of intensive studies to solve the above problems. That is, the present invention contains a copolymer (X) having a polyolefin (a) and an unsaturated (poly) carboxylic acid (anhydride) (b) as structural units and an acid value of 50 to 250 mgKOH / g. An inorganic filler-containing polyolefin resin composition containing the inorganic filler dispersant (A), the polyolefin resin (B), and the inorganic filler (C).

The inorganic filler-containing polyolefin resin composition of the present invention and a molded product formed by molding the resin composition have the following effects.
(1) The resin composition is excellent in dispersibility of the inorganic filler.
(2) A molded product formed by molding the resin composition is excellent in mechanical strength (impact resistance, bending elasticity, etc.) and thermal characteristics.

[Polyolefin (a)]
The polyolefin (a) in the present invention includes one or more (co) polymers of olefins, and a copolymer of one or more olefins and one or more other monomers. A polymer is included.
Examples of the olefin include alkenes having 2 to 30 carbon atoms (hereinafter abbreviated as C) such as ethylene, propylene, 1- and 2-butene, and isobutene, and C5-30 α-olefins (1-hexene, 1-hexene, Decene, 1-dodecene, etc.); other monomers include C4-30 unsaturated monomers having copolymerizability with olefins, such as vinyl acetate.

Specific examples of (a) include ethylene unit-containing (propylene unit-free) (co) polymers such as high, medium and low density polyethylene, and ethylene and C4-30 unsaturated monomers [butene (1- Butene, etc.), C5-30 α-olefin (1-hexene, 1-dodecene, etc.), vinyl acetate, etc.] (weight ratio is the moldability of the polyolefin resin composition and the molecular end of (a) and From the viewpoint of the amount of double bonds in the polymer chain, preferably 30/70 to 99/1, more preferably 50/50 to 95/5), etc .; propylene unit-containing (ethylene unit-free) (co) polymer For example, a copolymer of polypropylene, propylene and a C4-30 unsaturated monomer (same as above) (weight ratio is the same as above); ethylene / propylene copolymer (weight ratio is polyolefin resin) From the viewpoint of the moldability of the substrate and the amount of double bonds in the molecular terminal and / or polymer chain of (a), preferably 0.5 / 99.5 to 30/70, more preferably 2/98 to 20 /. 80); (co) polymers of C4 or higher olefins such as polybutene.
Among these, polyethylene, polypropylene, ethylene / propylene copolymer are preferable from the viewpoint of copolymerization with an unsaturated (poly) carboxylic acid (anhydride) (b) and an aliphatic unsaturated hydrocarbon (c) described later. Polymers, propylene / C4-30 unsaturated monomer copolymers, more preferably ethylene / propylene copolymers, and propylene / C4-30 unsaturated monomer copolymers.

  Number average molecular weight of (a) [hereinafter abbreviated as Mn. The measurement is based on a gel permeation chromatography (GPC) method described later. same as below. ] Is preferably 800 to 50,000, more preferably 1 from the viewpoint of the mechanical strength of the molded article of the composition containing the dispersant for inorganic filler (A) of the present invention and the productivity of (A). , 5,000 to 45,000.

The measurement conditions of Mn by GPC in the present invention are as follows.
Apparatus: High-temperature gel permeation chromatograph [“Alliance
GPC V2000 ", manufactured by Waters Corporation]
Solvent: Orthodichlorobenzene reference material: Polystyrene sample concentration: 3 mg / ml
Column stationary phase: PLgel 10 μm, MIXED-B 2 in series
[Made by Polymer Laboratories, Inc.]
Column temperature: 135 ° C

(A) is a molecular terminal and / or polymer chain from the viewpoint of polymerizability with an unsaturated (poly) carboxylic acid (anhydride) (b) or (b) and an aliphatic unsaturated hydrocarbon (c) described later. It preferably has a double bond inside.
The number of double bonds in the molecular terminal and / or polymer chain per 1,000 carbons (also referred to as 1,000 carbon atoms) of (a) [hereinafter, the number of double bonds per 1,000 carbons; May be abbreviated] is preferably from 0.1 to 20 from the viewpoint of the copolymerizability between (a) and (b) or (b) and (c) and the productivity of (A), Preferably it is 0.3-18 pieces, Most preferably, it is 0.5-15 pieces.
Here, the number of double bonds can be determined from the spectrum of (a) ¹ H-NMR (nuclear magnetic resonance) spectroscopy. That is, the peak in the spectrum is assigned, and from the integral value derived from the double bond at 4.5 to 6.0 ppm in (a) and the integral value derived from (a), the number of double bonds in (a) and ( The relative value of the carbon number of a) is determined, and the number of double bonds in the molecular end and / or polymer chain per 1,000 carbon atoms of (a) is calculated. The number of double bonds in the examples described later followed this method.

  The production method (a) includes polymerization methods (for example, those described in JP-A-59-206409) and degradation methods [thermal, chemical and mechanical degradation methods, etc. Examples of the formation method (hereinafter sometimes referred to as thermal degradation method) include those described in JP-B No. 43-9368, JP-B No. 44-29742, and JP-B No. 6-70094].

  The polymerization method includes a method of (co) polymerizing one or more of the olefins, and a method of copolymerizing one or more of the olefins and one or more of the other monomers. It is.

  In the degradation method, a polyolefin (a0) having a high molecular weight [preferably Mn 30,000 to 400,000, more preferably 50,000 to 200,000] obtained by the polymerization method is thermally, chemically or mechanically used. The method of degrading is included.

Among the degradation methods, in the thermal degradation method, the polyolefin (a0) is aerated with nitrogen and (1) in the absence of an organic peroxide (dicumyl peroxide, di-t-butyl peroxide, etc.) A method of thermally degrading continuously or discontinuously usually at 300 to 450 ° C. for 0.5 to 10 hours, and (2) 0.5 to 10 hours usually at 180 to 300 ° C. in the presence of an organic peroxide. A method of thermally degrading continuously or discontinuously is included.
Among these (1) and (2), from the viewpoint of the copolymerizability between (a) and (b) or (b) and (c) obtained, it is preferable that the molecular terminal and / or in the polymer chain. It is the method of (1) that it is easy to obtain those having a larger number of double bonds.

  Among these production methods of (a), those having a larger number of double bonds in the molecular ends and / or polymer chains are easily obtained, and (a) and (b) or (b) and (c) From the viewpoint of easy copolymerization of these, a degradation method is preferred, and a thermal degradation method is more preferred.

[Unsaturated (poly) carboxylic acid (anhydride) (b)]
The unsaturated (poly) carboxylic acid (anhydride) (b) in the present invention is a C3-30 (poly) carboxylic acid (anhydride) having one polymerizable unsaturated group. In the present invention, the unsaturated (poly) carboxylic acid (anhydride) means an unsaturated monocarboxylic acid, an unsaturated polycarboxylic acid and / or an unsaturated polycarboxylic anhydride.
Among these (b), as the unsaturated monocarboxylic acid, aliphatic (C3-24, for example, acrylic acid, methacrylic acid, α-ethylacrylic acid, crotonic acid, isocrotonic acid), alicyclic ring-containing (C6-24, Unsaturated poly (2-3 or more) carboxylic acids (anhydrides) include unsaturated dicarboxylic acids (anhydrides) [aliphatic dicarboxylic acids (anhydrides) (C4-24, for example, Maleic acid, fumaric acid, itaconic acid, citraconic acid, mesaconic acid, and anhydrides thereof), alicyclic dicarboxylic acids (anhydrides) (C8-24, such as cyclohexene dicarboxylic acid, cycloheptene dicarboxylic acid, bicyclo) Heptene dicarboxylic acid, methyltetrahydrophthalic acid, and anhydrides thereof)], unsaturated tricarboxylic acid (anhydride) [aliphatic Recarboxylic acids (anhydrides) (C5-24, eg aconitic acid, 3-butene-1,2,3-tricarboxylic acid, 4-pentene-1,2,4-tricarboxylic acid, and anhydrides thereof), alicyclic Containing tricarboxylic acids (anhydrides) (C9-24, such as 4-cyclohexene-1,2,3-tricarboxylic acid, 4-cycloheptene-1,2,3-tricarboxylic acid and anhydrides thereof) and the like. . The above (b) may be used alone or in combination of two or more.
Of the above (b), an unsaturated dicarboxylic acid (anhydride) is preferable from the viewpoint of copolymerization with the aliphatic unsaturated hydrocarbon (c) described later, and an aliphatic unsaturated dicarboxylic acid (anhydride) is more preferable. Particularly preferred are aliphatic unsaturated dicarboxylic acid anhydrides, and most preferred is maleic anhydride.

[Aliphatic unsaturated hydrocarbon (c)]
In the aliphatic unsaturated hydrocarbon (c) in the present invention, a C2-30 alkene, a C6-36 (more preferably C8-30) linear α-olefin and a branched chain constituting the (a) are included. In addition to the α-olefin, C4-30 other unsaturated monomers (vinyl acetate, butadiene, etc.) having copolymerizability with olefin are included.
Examples of the linear α-olefin include 1-hexene, 1-octene, 1-nonene, 1-decene, and a mixture of two or more thereof.
Examples of the α-olefin having a branched chain include propylene trimer, propylene tetramer, and a mixture of two or more thereof.
Among the above (c), the copolymer is preferable from the viewpoints of copolymerization with (a) and (b), mechanical strength of the molded product described later, and dispersibility imparting effect of the resulting dispersant for inorganic filler (A). , C6-36 (more preferably C8-30), linear α-olefins and branched α-olefins.

[Radical initiator (d)]
In the copolymer (X) in the present invention, the (a), (b), or (a), (b), (c) is a radical generation source [radical initiator (d), heat, light, etc. ] Is obtained by copolymerization in the presence of
Examples of the radical initiator (d) include azo compounds [azobisisobutyronitrile, azobisisovaleronitrile, etc.], peroxides [monofunctional (having one peroxide group in the molecule) (benzoyl peroxide). , Di-t-butyl peroxide, lauroyl peroxide, dicumyl peroxide, etc.) and polyfunctional (having two or more peroxide groups in the molecule) [2,2-bis (4,4-di-t- Butylperoxycyclohexyl) propane, di-t-butylperoxyhexahydroterephthalate, diallylperoxydicarbonate, etc.]] and the like.
Among these, (a), (b), or (a), (b), (c) graft copolymerization viewpoint, that is, as will be described later, (a) is a trunk, (b) or (b) From the viewpoint of the formation of a graft copolymer having a (co) polymer of (c) as a branch, a peroxide is preferable, a monofunctional peroxide is more preferable, and di-t-butyl is particularly preferable. Peroxide, lauroyl peroxide, dicumyl peroxide.

  The use amount of (d) is preferably based on the total weight of (a), (b) or the total weight of (a), (b), (c) from the viewpoint of reactivity and side reaction suppression. 0.05 to 10%, more preferably 0.2 to 5%, particularly preferably 0.5 to 3%.

[Copolymer (X)]
The copolymer (X) in the present invention comprises the polyolefin (a) and the unsaturated (poly) carboxylic acid (anhydride) (b) as structural units.
Further, (X) is an aliphatic unsaturated hydrocarbon (c) added to the above structural unit from the viewpoint of increasing the copolymerization ratio of (b) and further improving the dispersibility imparting effect of the dispersant for inorganic filler (A). It is preferable to add a copolymer having (a), (b) and (c) as structural units.
In the production of (X), styrene or a styrene derivative (thing of C9 to C15, for example, methylstyrene, α-methylstyrene, p-methoxystyrene, m-butylstyrene, etc.) is not included as a structural unit of copolymerization. Is preferable from the viewpoint of dispersibility of the inorganic filler (C).

  The weight ratio [(a) / (b)] of (a) and (b) in (X) is the compatibility of the dispersant (A) with the polyolefin resin (B) described later and the inorganic filler (C). From the viewpoint of dispersibility and the mechanical strength of the molded product, it is preferably 30/70 to 92/8, more preferably 35/65 to 80/20; the weight ratio of (a) to (c) [(a) / (c )] Is preferably 23/77 to 94/6, more preferably 30/70 to 85/15 from the same viewpoint; the weight ratio of (a) to the sum of (b) and (c) [(a ) / [(B) + (c)]] is preferably 20/80 to 85/15, more preferably 30/70 to 80/20 from the same viewpoint; and the weight of (b) and (c) The ratio [(b) / (c)] indicates the dispersibility of the inorganic filler (C), the mechanical strength of the molded article, and the dispersant (A) and the polyolefin. Preferably from the viewpoint of compatibility with the emission resin (B) 11 / 89~90 / 10, more preferably from 15 / 85-80 / 20.

  The content of each component based on the total weight of (a), (b), and (c) is as follows. (A) is a dispersant (A) containing the copolymer (X) and a polyolefin resin (B). ) And the dispersibility of the inorganic filler (C) and the mechanical strength of the molded product are preferably 20 to 85%, more preferably 30 to 80%; (b) is the dispersion of the inorganic filler (C) From the viewpoint of the compatibility, the mechanical strength of the molded product and the compatibility between the dispersant (A) and the polyolefin resin (B), preferably 8 to 45%, more preferably 10 to 40%; (c) is usually 70% or less. From the viewpoint of optimizing the balance between the dispersibility of (C) and the mechanical strength of the molded product, it is preferably 5 to 65%, more preferably 10 to 50%.

  Copolymer (X) is preferably polyolefin (a) and unsaturated (poly) carboxylic acid (anhydride) (b) or (a), (b) and in the presence of a radical initiator (d). It can be produced by copolymerizing an aliphatic unsaturated hydrocarbon (c).

The specific production method (X) includes the following methods [1] and [2].
[1] (a), (b), or (a), (b), (c) is a suitable organic solvent [C2-18, such as hydrocarbon (hexane, heptane, octane, dodecane, benzene, toluene, xylene) Etc.), halogenated hydrocarbons (di-, tri-, and tetrachloroethane, dichlorobutane, etc.), ketones (acetone, methyl ethyl ketone, di-t-butyl ketone, etc.), ethers (ethyl-n-propyl ether, di-n-) Butyl ether, di-t-butyl ether, dioxane, etc.)], and if necessary, (d) [or a solution in which (d) is dissolved in an appropriate organic solvent (the same as above)], which will be described later. A chain transfer agent (t) and a polymerization inhibitor (f), and stirring with heating (solution method);
[2] (a), (b), or (a), (b), (c), and (d), (t), (f), if necessary, are mixed in advance, an extruder, a Banbury mixer, a kneader A method of melting and kneading using a method (melting method).

  The reaction temperature in the solution method may be any temperature at which (a) is dissolved in an organic solvent. (A), (b), or (a), (b), (c) copolymerizability and productivity From this viewpoint, it is preferably 50 to 220 ° C, more preferably 110 to 210 ° C, and particularly preferably 120 to 180 ° C.

  The reaction temperature in the melting method may be any temperature at which (a) melts, and (a), (b), or (a), (b), (c) copolymerizability and reaction product. From the viewpoint of the decomposition temperature, it is preferably 120 to 260 ° C, more preferably 130 to 240 ° C.

Examples of the chain transfer agent (t) include alcohols (C1-24, such as methanol, ethanol, 1-propanol, 2-butanol, allyl alcohol); thiols (C1-24, such as ethanethiol, propanethiol, 1- and 2-butanethiol, 1-octanethiol); aldehydes (C2-18, such as n- and sec-butyraldehyde, 1-pentylaldehyde); phenols (C6-36, such as phenol, o-, m- and p-cresol) ); Amines (C3-24, such as diethyl methylamine, triethylamine, diphenylamine); disulfides (C2-24, such as diethyl disulfide, di-1-propyl disulfide).
The amount of (t) used is usually 30% or less based on the total weight of (a), (b) or the total weight of (a), (b), (c), (a), (b) Or from the viewpoint of copolymerization and productivity of (a), (b), and (c), preferably 0.1 to 20%.

Examples of the polymerization inhibitor (f) include catechol (C6-36, for example, 2-methyl-2-propylcatechol), quinone (C6-24, for example, p-benzoquinone), hydrazine (C2-36, for example, 1, 3, 5-triphenylhydrazine), nitro compounds (C3-24, such as nitrobenzene), stabilized radicals [C5-36, such as 1,1-diphenyl-2-picrylhydrazyl (DPPH), 2,2,6,6 -Tetramethyl-1-piperidinyl oxide (TEMPO)].
The amount of (f) used is usually 5% or less based on the total weight of (a), (b), or the total weight of (a), (b), (c), productivity, (a), From the viewpoint of the stability of (b) and (c) and the reactivity of (a), (b) and (c), it is preferably 0.01 to 0.5%.

  Mn of (X) is preferably 1,500 to 70,000, more preferably 2,000 to 60,000, particularly preferably 2 from the viewpoint of the mechanical strength of the molded product and the moldability of the resin composition described later. , 500 to 50,000.

The acid value of (X) is 50 to 250 mg KOH / g (only numerical values are shown below), the dispersibility of the inorganic filler (C), and the compatibility viewpoint between the dispersant (A) and the polyolefin resin (B) described later. To preferably 65 to 200, particularly preferably 80 to 180. When the acid value of (X) is less than 50, the dispersibility of the inorganic filler (C) is deteriorated, and when it exceeds 250, the compatibility between the dispersant (A) and the polyolefin resin (B) described later is deteriorated.
The acid value here is a value obtained by measurement according to the following procedures (i) to (iii) according to JIS K0070.
(I) 1 g of (X) is dissolved in 100 g of xylene adjusted to 100 ° C.
(Ii) Titration with 0.1 mol / L potassium hydroxide ethanol solution [trade name “0.1 mol / L ethanolic potassium hydroxide solution”, manufactured by Wako Pure Chemical Industries, Ltd.] using phenolphthalein as an indicator at the same temperature. I do.
(Iii) The amount of potassium hydroxide required for titration is converted to mg, and the acid value (unit: mgKOH / g) is calculated.
In the above measurement, one acid anhydride group is equivalent to one carboxyl group. The acid value in the examples described later was in accordance with this method.

Examples of the method for bringing the acid value of (X) into the above range include the following methods.
(1) A method in which the constituent units of (a) and (b) are copolymerized under a condition of being suspended or dissolved in an appropriate organic solvent and heating and stirring.
(2) A method in which a structural unit obtained by adding (c) to (a) and (b) is copolymerized in the same manner as in (1).
Specifically, the above-described method is carried out by using (a) and (b) or (a), (b) and (c) in a suitable organic solvent [C2-18, such as hydrocarbon (hexane, heptane, octane, decane). , Dodecane, benzene, toluene, xylene, etc.), halogenated hydrocarbons (di-, tri- and tetrachloroethane, dichlorobutane, etc.), ketones (acetone, methyl ethyl ketone, diethyl ketone, di-t-butyl ketone, etc.), ether (ethyl) -N-propyl ether, di-i-propyl ether, di-n-butyl ether, di-t-butyl ether, dioxane, etc.)] and the like, and if necessary, (d) [or (d) Solution in a suitable organic solvent (the same as above)], the chain transfer agent (t) and the polymerization inhibitor (f) are added and stirred with heating. It can be carried out.
Of the above (1) and (2), (2) is easy to control the copolymerization rate of (b) by adding (c) to the structural unit, and the acid value of (X) is easily within the above range. To a preferred method.

Moreover, the following are contained in the form of copolymer (X).
[1] A graft copolymer in which (a) is a trunk and (b) or a (co) polymer of (b) and (c) is a branch.
[2] A random and / or block copolymer of (a) and (b), or (a), (b) and (c).
The form of the above [1] is (d), preferably in the presence of a peroxide, (a) and (b) or (a), (b) and (c) are heated and melted, or in an appropriate organic solvent. It can be formed by suspending or dissolving, and further adding the chain transfer agent (t) and the polymerization inhibitor (f) as necessary and stirring with heating.
The form of [2] is (d), preferably in the presence of an azo compound, (a) and (b), or (a), (b) and (c) are heated and melted or suspended in a suitable organic solvent. It can be formed by turbidity or dissolution and, if necessary, adding a chain transfer agent (t) and a polymerization inhibitor (f) described later and stirring with heating.
Of the forms [1] and [2], the form [1] is preferable from the viewpoint of dispersibility of the inorganic filler (C).

[Dispersant for inorganic filler (A)]
The dispersant for inorganic filler (A) in the present invention is a co-polymer having the polyolefin (a) and the unsaturated (poly) carboxylic acid (anhydride) (b) as structural units and an acid value of 50 to 250 mgKOH / g. Containing coalescence (X).
The dispersant (A) in the present invention is used as a dispersant for (C) in a polyolefin resin composition comprising a polyolefin resin (B) and an inorganic filler (C) described later.

[Polyolefin resin (B)]
(B) includes a polymerization method exemplified as the production method of (a), or a degradation (thermal, chemical and mechanical degradation) method of a high molecular weight polyolefin (preferably Mn 80,000 to 400,000). For example, an ethylene unit-containing (propylene unit-free) (co) polymer, a propylene unit-containing (ethylene-unit-free) (co) polymer, an ethylene / propylene copolymer, and (Co) polymers of C4 or higher olefins are included.

  As a combination of (A) and (B), the case where the structural unit of (B) and the structural unit of the polyolefin (a) constituting (A) are the same or similar are the cases of (A) and (B) It is preferable from the viewpoint of compatibility. For example, when (B) is a propylene unit-containing (ethylene unit-free) (co) polymer, (a) constituting (A) is also a propylene unit-containing (ethylene unit-free) (co) polymer. Some cases are preferred.

  Mn of (B) is preferably 10,000 to 500,000, more preferably 20,000 to 400,000 from the viewpoint of mechanical strength of the polyolefin resin substrate and compatibility with (A).

[Inorganic filler (C)]
Examples of (C) include various types, for example, the following (C1) to (C8), and mixtures thereof.
(C1) oxide (for example, silica, alumina, titanium oxide, wollastonite, calcined kaolin, wollastonite);
(C2) hydroxide (for example, magnesium hydroxide, calcium hydroxide, aluminum hydroxide);
(C3) silicates (eg talc, mica, clay, dolomite, bentonite, silica, calcium silicate, zeolite);
(C4) carbonate (for example, calcium carbonate, magnesium carbonate);
(C5) metal salts (eg barite, fluorite, calcium sulfate);
(C6) metal sulfide (for example, molybdenum disulfide);
(C7) inorganic microballoons (eg glass, shirasu);
(C8) Metal powder (for example, aluminum powder, copper powder).
Of these (C), (C1), (C2), (C3) and (C4) are preferred from the mechanical strength and industrial viewpoint of the molded article, and (C1) and (C2) are more preferred. And (C3), particularly preferred are talc, magnesium carbonate and magnesium hydroxide.

  The particle diameter of (C) is not particularly limited, but the volume average particle diameter of (C) is preferably from 0.1 to 1,000 μm, more preferably from the viewpoint of mechanical strength and moldability of the molded product. It is 5-500 micrometers, Most preferably, it is 1-100 micrometers.

[Inorganic filler-containing polyolefin resin composition]
The inorganic filler-containing polyolefin resin composition of the present invention contains the dispersant (A), the polyolefin resin (B), and the inorganic filler (C).
In the resin composition, the proportion of each component based on the total weight of (A), (B), and (C) is preferably (A) from the viewpoint of the dispersibility of (C) and the mechanical strength of the molded product. Is 0.1 to 15%, more preferably 0.5 to 12%, particularly preferably 1 to 10%; (B) is preferably 30 to 98% from the viewpoint of the productivity and mechanical strength of the molded product, More preferably 40 to 85%, particularly preferably 50 to 80%; (C) is preferably 1 to 60%, more preferably 5 to 55%, particularly preferably from the viewpoint of mechanical strength and productivity of the molded article. Is 10 to 50%.

The inorganic filler-containing polyolefin resin composition of the present invention can further contain various additives (G) as necessary within a range not inhibiting the effects of the present invention.
(G) includes colorant (G1), flame retardant (G2), lubricant (G3), antistatic agent (G4), dispersant (G5) other than (A), antioxidant (G6), and ultraviolet absorption 1 type (s) or 2 or more types selected from the group which consists of an agent (G7) are mentioned.

Examples of the colorant (G1) include pigments and dyes.
Examples of the pigment include inorganic pigments (such as graphite); organic pigments (such as azo lakes).
Examples of the dye include azo series and anthraquinone series.

  Examples of the flame retardant (G2) include organic flame retardants [nitrogen-containing compounds [salts such as urea compounds and guanidine compounds], sulfur-containing compounds [sulfuric esters, sulfamic acids, and their salts, esters, amides, etc.], silicon-containing compounds Compound [polyorganosiloxane, etc.], phosphorus-containing [phosphate ester, etc.]], and the like.

  Examples of the lubricant (G3) include waxes (such as carnauba wax), higher fatty acids (such as stearic acid), higher alcohols (such as stearyl alcohol), and higher fatty acid amides (such as stearic acid amide).

Antistatic agents (G4) include nonionic, cationic, anionic and amphoteric surfactants described below and in US Pat. Nos. 3,929,678 and 4,331,447. .
(1) Nonionic surfactant Alkylene oxide (hereinafter abbreviated as AO) addition type nonionics, for example, active hydrogen atom-containing compound having a hydrophobic group (C8-24 or more) [saturated and unsaturated, higher alcohol (C8-18), higher aliphatic amines (C8-24) and higher fatty acids (C8-24) etc.] (poly) oxyalkylene derivatives (higher fatty acid mono- and di-esters of AO adducts and polyalkylene glycols) A (poly) oxyalkylene derivative of a higher fatty acid (C8-24) ester of a polyhydric alcohol (C3-60) (Tween type nonionics, etc.); a (poly) oxyalkylene derivative of a (alkanol) amide of a higher fatty acid (above) A (poly) oxyalkylene of a polyhydric alcohol (above) alkyl (C3-60) ether Derivatives; and polyoxypropylene polyols [polyoxypropylene derivatives of polyhydric alcohols and polyamines (C2-10) (pluronic and tetronic nonionics)]; polyhydric alcohols (above) type nonionics (for example of polyhydric alcohols) Fatty acid esters, polyhydric alcohol alkyl (C3-60) ethers, and fatty acid alkanolamides); and amine oxide type nonionics [eg (hydroxy) alkyl (C10-18) di (hydroxy) alkyl (C1-3) amine oxide ].

(2) Cationic surfactants Quaternary ammonium salt-type cationix [tetraalkyl ammonium salt (C11-100) alkyl (C8-18) trimethylammonium salt and dialkyl (C8-18) dimethylammonium salt etc.]; trialkyl Benzylammonium salt (C17-80) (lauryldimethylbenzylammonium salt etc.); alkyl (C8-60) pyridinium salt (cetylpyridinium salt etc.); (poly) oxyalkylene (C2-4) trialkylammonium salt (C12-100) ) (Polyoxyethylene lauryl dimethyl ammonium salt, etc.); and acyl (C8-18) aminoalkyl (C2-4) or acyl (C8-18) oxyalkyl (C2-4) tri [(hydroxy) alkyl (C1-4 ]] Ammoni Um salts (sapamine type quaternary ammonium salts) [these salts include, for example, halides (chlorides, bromides, etc.), alkyl sulfates (methosulphate, etc.) and organic acids (below); and amine salt types Cationics: 1-3 primary amines [for example, higher aliphatic amines (C12-60), polyoxyalkylene derivatives of aliphatic amines (methylamine, diethylamine, etc.) [ethylene oxide (hereinafter abbreviated as EO) adducts, etc.], and acyl Aminoalkyl or acyloxyalkyl (above) di (hydroxy) alkyl (above) amine (such as stearoyloxyethyl dihydroxyethylamine, stearamide ethyl diethylamine)], inorganic acid (hydrochloric acid, sulfuric acid, nitric acid, phosphoric acid etc.) salt and organic Acid (C2-22) salt.

(3) Anionic surfactant Higher fatty acid (above) salt (such as sodium laurate), ether carboxylic acid [carboxymethylated product of EO (1-10 mol) adduct, etc.], and salts thereof; sulfate salt ( Alkyl and alkyl ether sulfates, etc.), sulfated oils, sulfated fatty acid esters and sulfated olefins; sulfonates [alkylbenzene sulfonates, alkylnaphthalene sulfonates, sulfosuccinic acid dialkyl ester types, α-olefins (C12-18) Sulfonates, N-acyl-N-methyl taurine (Igepon T type, etc.)], and phosphate ester salts (alkyl, alkyl ethers, alkylphenyl ether phosphates, etc.).

(4) Amphoteric surfactant:
Carboxylic acid (salt) type amphoterics [amino acid type amphoterics (such as laurylaminopropionic acid (salt)) and betaine type amphoterics (such as alkyldimethylbetaine and alkyldihydroxyethylbetaine)]; sulfuric acid Ester (salt) type amphoterics [sulfuric ester (salt) of laurylamine, hydroxyethyl imidazoline sulfate ester (salt), etc.]; sulfonic acid (salt) type amphoterics [pentadecyl sulfotaurine, imidazoline sulfonic acid ( Salt) etc.], and phosphate ester (salt) type amphoterics etc. [phosphate ester (salt) etc. of glycerol lauryl ester].

  Salts in the above anionic and amphoteric surfactants include metal salts, such as salts of alkali metals (lithium, sodium, potassium, etc.), alkaline earth metals (calcium, magnesium, etc.) and group IIB metals (zinc, etc.); Ammonium salts; and amine salts and quaternary ammonium salts.

  Examples of the dispersant (G5) include polymers having Mn of 1,000 to 20,000, such as vinyl resin [polyolefin (polyethylene, polypropylene, etc.), modified polyolefin [polyethylene oxide (polyethylene oxidized with ozone etc., carboxyl group, carbonyl group and And / or those having a hydroxyl group introduced therein), and vinyl resins other than the above polyolefins (polyhalogenated vinyl [polyvinyl chloride, polyvinyl bromide, etc.], polyvinyl acetate, polyvinyl alcohol, polymethyl vinyl ether, poly (meta ) Acrylic acid, poly (meth) acrylic acid ester [poly (meth) methyl acrylate etc.] and styrene resin [polystyrene, acrylonitrile / styrene (AS) resin etc.] etc .; polyester resin [polyethylene terephthalate etc.], polyamid Examples include resins [6,6-nylon, 12-nylon, etc.], polyether resins [polyethersulfone, etc.], polycarbonate resins [polycondensates of bisphenol A and phosgene, etc.], and block copolymers thereof. .

  Antioxidants (G6) include hindered phenol compounds [pt-amylphenol-formaldehyde resin, nordihydroguaiaretic acid (NDGA), 2,6-di-tert-butyl-4-methylphenol (BHT). ), 2-t-butyl-4-methoxyphenol (BHA), 6-t-butyl-2,4, -dimethylphenol (24M6B), 2,6-di-t-butylphenol (26B) and the like];

  Sulfur-containing compounds [N, N'-diphenylthiourea, dimyristylthiodipropionate, etc.];

  Phosphorus-containing compound [2-t-butyl-α- (3-t-butyl-4-hydroxyphenyl) -p-cumenylbis (p-nonylphenyl) phosphite, dioctadecyl-4-hydroxy-3,5-di- t-butylbenzylphosphonate and the like] and the like.

  Examples of the ultraviolet absorber (G7) include salicylate compounds [phenyl salicylate and the like]; benzophenone compounds [2,4-dihydroxybenzophenone and the like]; benzotriazole compounds [2- (2′-hydroxy-5′-methylphenyl)- Benzotriazole, etc.].

The total content of (G) in the inorganic filler-containing polyolefin resin composition is usually 20% or less based on the total weight of the composition, preferably from the viewpoint of functional expression of each (G) and an industrial viewpoint. 05 to 10%, more preferably 0.1 to 5%.
The amount of each additive used based on the total weight of the composition is as follows: (G1) is usually 5% or less, preferably 0.1 to 3%; (G2) is usually 8% or less, preferably 1 to 3%; (G3) is usually 8% or less, preferably 1 to 5%; (G4) is usually 8% or less, preferably 1 to 3%; (G5) is usually 1% or less, preferably 0.1 to 0.5%. %; (G6) is usually 2% or less, preferably 0.05 to 0.5%; (G7) is usually 2% or less, preferably 0.05 to 0.5%.

  When the additive is the same and overlaps between the above (G1) to (G7), the amount of each additive having the corresponding additive effect is not used as it is, but the effect as the other additive is simultaneously achieved. Considering what is obtained, the usage amount is adjusted according to the purpose of use.

As a method for producing the inorganic filler-containing polyolefin resin composition of the present invention,
(1) A method (collective method) in which (A), (B), (C) and, if necessary, (G) are mixed at once to form an inorganic filler-containing polyolefin resin composition;
(2) A masterbatch polyolefin resin composition containing a high concentration of (A) is prepared by mixing a part of (B), the total amount of (A), and if necessary, a part or all of (G). Then, the remaining (B), (C) and, if necessary, the remaining (G) are added and mixed to prepare an inorganic filler-containing polyolefin resin composition (masterbatch method).
The method (2) is preferable from the viewpoint of the mixing efficiency of (A).

As a specific mixing method in the method for producing the inorganic filler-containing polyolefin resin composition,
(I) For each component to be mixed, for example, a powder mixer [“Henschel Mixer” [trade name “Henschel Mixer FM150L / B”, Mitsui Mining Co., Ltd., after changing the company name, manufactured by Nippon Coke Industries, Ltd.], “ After mixing with “Nauter Mixer” [trade name “Nauter Mixer DBX3000RX”, manufactured by Hosokawa Micron Co., Ltd.], “Banbury Mixer” [trade name “MIXTRON BB-16MIXER”, manufactured by Kobe Steel, Ltd.], etc.] A method of kneading usually at 120 to 220 ° C. for 2 to 30 minutes using a melt kneader [batch kneader, continuous kneader (single screw kneader, biaxial kneader, etc.)];
(Ii) A method of directly kneading the components to be mixed under the same conditions using the same melt-kneading apparatus as described above without mixing powders in advance.
Among these methods, the method (i) is preferable from the viewpoint of mixing efficiency.

  The inorganic filler-containing polyolefin composition of the present invention is excellent in dispersibility of the inorganic filler, and the molded product described later is excellent in mechanical strength and thermal characteristics. The mechanical strength of the molded product can be evaluated by impact resistance, bending elastic modulus, and the like, which will be described later, and thermal characteristics can be evaluated by load deflection temperature, which will be described later. On the other hand, the dispersibility of the inorganic filler can be evaluated by the affinity between the polyolefin resin (B) and the inorganic filler (C) described later.

[Molded articles and molded articles]
The molded article of the present invention is formed by molding the inorganic filler-containing polyolefin resin composition.
Examples of molding methods include injection molding, compression molding, calendar molding, slush molding, rotational molding, extrusion molding, blow molding, film molding (casting method, tenter method, inflation method, etc.), etc., depending on the purpose. Molding, multilayer molding, foam molding and the like can be performed by any method that incorporates means. Examples of the form of the molded product include a plate shape, a sheet shape, a film, a woven fabric, and a fiber (including a nonwoven fabric).

The molded article of the present invention has excellent mechanical strength and good paintability and printability, and a molded article can be obtained by coating and / or printing the molded article.
Examples of the method for coating the molded product include, but are not limited to, air spray coating, airless spray coating, electrostatic spray coating, immersion coating, roller coating, and brush coating.
Examples of the paint include paints generally used for plastic coating such as polyester melamine resin paint, epoxy melamine resin paint, acrylic melamine resin paint, acrylic urethane resin paint, and these so-called relatively high-polarity paints, Further, paints with low polarity (such as olefins) can also be used.
The coating film thickness (dry film thickness) can be appropriately selected according to the purpose, but is usually 10 to 50 μm.

Further, as a method for further printing after coating the molded product or the molded product, any printing method generally used for plastic printing can be used. For example, gravure printing, flexographic printing, Examples include printing, screen printing, pad printing, dry offset printing, and offset printing.
As the printing ink, those usually used for printing plastics, for example, gravure ink, flexographic ink, screen ink, pad ink, dry offset ink and offset ink can be used.

  EXAMPLES The present invention will be further described below with reference to examples, but the present invention is not limited to these examples. In the examples, “part” means “part by weight” and “%” other than mol% means “% by weight”.

[Polyolefin (a)]
Production Example 1
Polyolefin (a0-1) having a structural unit of 98 mol% propylene and 2 mol% ethylene in a reaction vessel [trade name “Sun Allomer PZA20A”, manufactured by Sun Allomer Co., Ltd., Mn 100,000, molecules per 1,000 carbons 0 double bonds in terminal and / or polymer chain, and so on. 100 parts were charged in a nitrogen atmosphere, heated and melted with a mantle heater while nitrogen was passed through the gas phase, and subjected to heat degradation at 360 ° C. for 70 minutes with stirring to obtain polyolefin (a-1). . In (a-1), the number of double bonds in the molecular terminal and / or polymer chain per 1,000 carbon atoms was 7.2, and Mn was 3,000.

Production Example 2
In Production Example 1, a polyolefin (a-2) was obtained in the same manner as in Production Example 1 except that the heat degradation time was changed from 70 minutes to 100 minutes. In (a-2), the number of double bonds in molecular ends and / or polymer chains per 1,000 carbon atoms was 18, and Mn was 1,200.

Production Example 3
In Production Example 1, a polyolefin (a-3) was obtained in the same manner as in Production Example 1 except that the heat degradation time was changed from 70 minutes to 20 minutes. In (a-3), the number of double bonds in the molecular terminal and / or polymer chain per 1,000 carbon atoms was 0.3, and Mn was 45,000.

Production Example 4
In Production Example 1, instead of 100 parts of polyolefin (a0-1), polyolefin (a0-2) having a structural unit of 80 mol% of propylene and 20 mol% of 1-butene [trade name “Tuffmer XM-5080”, Mitsui Chemical Co., Ltd., Mn 90,000, and so on. ] Except having used 100 parts, it carried out similarly to manufacture example 1 and obtained polyolefin (a-4). In (a-4), the number of double bonds in the molecular terminal and / or polymer chain per 1,000 carbon atoms was 7.2, and Mn was 3,000.

Production Example 5
In Production Example 1, a polyolefin (a-5) was obtained in the same manner as in Production Example 1 except that the heat degradation time was changed from 70 minutes to 120 minutes. In (a-5), the number of double bonds in molecular ends and / or polymer chains per 1,000 carbon atoms was 36, and Mn was 600.

Production Example 6
In Production Example 1, a polyolefin (a-6) was obtained in the same manner as in Production Example 1 except that the heat degradation time was changed from 70 minutes to 10 minutes. In (a-6), the number of double bonds in the molecular terminal and / or polymer chain per 1,000 carbon atoms was 0.05, and Mn was 65,000.

[Dispersant for inorganic filler]
Production Example 7
A reaction vessel was charged with 100 parts of (a-1), 24 parts of maleic anhydride (b-1), 18.5 parts of 1-decene (c-1), and 100 parts of xylene. The mixture was heated to 130 ° C. and dissolved uniformly. A solution prepared by dissolving 0.5 part of dicumyl peroxide [trade name “Park Mill D”, manufactured by NOF Corporation] (d-1) in 10 parts of xylene was added dropwise over 10 minutes, and then refluxed with xylene. Stirring was continued for 3 hours. Thereafter, xylene and unreacted maleic anhydride are distilled off under reduced pressure (1.5 kPa, the same shall apply hereinafter) to disperse the inorganic filler dispersant (A-1) containing the copolymer (X-1). ) (X-1) had an acid value of 95 and Mn of 5,000.

Production Example 8
In Production Example 7, instead of (a-1) 100 parts, (b-1) 24 parts, (c-1) 18.5 parts, (a-2) 100 parts, (b-1) 100 parts, (C-1) Except having used 85.7 parts, it carried out similarly to manufacture example 7, and obtained the dispersing agent (A-2) for inorganic fillers containing a copolymer (X-2). (X-2) had an acid value of 200 and Mn of 4,000.

Production Example 9
In Production Example 7, (b-1) 32.7 parts and (c-1) 23.6 parts were used in place of (b-1) 24 parts and (c-1) 18.5 parts. Was carried out in the same manner as in Production Example 7 to obtain an inorganic filler dispersant (A-3) containing the copolymer (X-3). (X-3) had an acid value of 120 and Mn of 5,000.

Production Example 10
In Production Example 7, instead of 100 parts of (a-1), the same procedure as in Production Example 7 was carried out except that 100 parts of (a-4) was used, and the copolymer (X-4) was contained. A dispersant for inorganic filler (A-4) was obtained. (X-4) had an acid value of 95 and Mn of 5,000.

Production Example 11
Instead of (a-1) 100 parts, (b-1) 24 parts, (c-1) 18.5 parts in Production Example 7, (a-2) 100 parts, (b-1) 116.8 parts , 1-hexene (c-2), except that 50.5 parts were used, the same procedure as in Production Example 7 was carried out, and the inorganic filler dispersant (A-5) containing the copolymer (X-5) was used. ) (X-5) had an acid value of 250 and Mn of 2,500.

Production Example 12
In Production Example 7, in place of 18.5 parts of (c-1), except that 3.8 parts of (c-2) were used, the same procedure as in Production Example 7 was carried out to obtain copolymer (X-6). An inorganic filler dispersant (A-6) was obtained. (X-6) had an acid value of 108 and Mn of 4,800.

Production Example 13
In Production Example 7, instead of 24 parts of (b-1) and 18.5 parts of (c-1), 33 parts of (b-1), 1-hexatriacontene (C36 α-olefin) (c-3) ) Except having used 200 parts, it carried out similarly to manufacture example 7, and obtained the dispersing agent (A-7) for inorganic fillers containing a copolymer (X-7). (X-7) had an acid value of 57 and Mn of 7,000.

Production Example 14
In Production Example 7, (a-2) 100 parts, (b-1) 19 parts are used instead of (a-1) 100 parts, (b-1) 24 parts, (c-1) 18.5 parts. And it carried out similarly to manufacture example 7 except not using (c-1), and obtained the dispersing agent (A-8) for inorganic fillers formed by containing the copolymer (X-8). (X-8) had an acid value of 91.5 and Mn of 1,600.

Production Example 15
Instead of 24 parts (b-1), 18.5 parts (c-1), and 0.5 parts (d-1) in Production Example 7, (b-1) 25 parts, (c-1) 18 parts , 1,1′-azobis (cyclohexane-1-carbonitrile) [trade name “V-40”, manufactured by Wako Pure Chemical Industries, Ltd.] (d-2) It carried out similarly to Example 7 and obtained the dispersing agent (A-9) for inorganic fillers containing a copolymer (X-9). (X-9) had an acid value of 100 and Mn of 4,500.

Production Example 16
In Production Example 7, (a-1) 100 parts, (b-1) 24 parts, (c-1) 18.5 parts instead of (a-3) 100 parts, (b-1) 13.4 parts (C-2) Except having used 8.5 parts, it carries out similarly to manufacture example 7, and obtains the dispersing agent (A-10) for inorganic fillers containing a copolymer (X-10). It was. (X-10) had an acid value of 65 and Mn of 50,000.

Production Example 17
In Production Example 7, (a-1) 100 parts, (b-1) 24 parts, (c-1) 18.5 parts instead of (a-2) 100 parts, (b-1) 18.2 parts (C-2) Except having used 11.6 parts, it carries out similarly to manufacture example 7, and obtains the dispersing agent (A-11) for inorganic fillers containing a copolymer (X-11). It was. (X-11) had an acid value of 80 and Mn of 2,200.

Production Example 18
In Production Example 7, it was carried out in the same manner as in Production Example 7 except that 31 parts of itaconic acid (b-2) was used instead of 24 parts of (b-1), and contained copolymer (X-12). Thus obtained dispersant for inorganic filler (A-12) was obtained. (X-12) had an acid value of 179 and Mn of 4,600.

Production Example 19
In Production Example 7, instead of (b-1) 24 parts and (c-1) 18.5 parts, 17.6 parts of acrylic acid, 18.5 parts of (c-1) and 1-octadecene [trade name “Linearene 18 ”, Idemitsu Kosan Co., Ltd., C18 α-olefin] (c-4), except that 2.7 parts were used, and the copolymer (X-13) was contained in the same manner as in Production Example 7. An inorganic filler dispersant (A-13) was obtained. (X-13) had an acid value of 95 and Mn of 5,000.

Production Example 20
In Production Example 7, instead of (a-1) 100 parts, (b-1) 24 parts, (c-1) 18.5 parts, (a0-1) 100 parts, maleic acid 6 parts, (c- 1) Except having used 3 parts, it carried out similarly to manufacture example 7, and obtained the dispersing agent (A-14) for inorganic fillers containing a copolymer (X-14). (X-14) had an acid value of 53 and Mn of 105,000.

Production Example 21
In Production Example 7, Production Example 7 except that (b-1) 250 parts and (c-1) 250 parts were used instead of (b-1) 24 parts and (c-1) 18.5 parts. It carried out similarly to and obtained the dispersing agent (A-15) for inorganic fillers containing a copolymer (X-15). (X-15) had an acid value of 238 and Mn of 6,000.

Comparative production example 1
In Production Example 7, (a-1) 100 parts, (b-1) 24 parts, (c-1) 18.5 parts instead of (a-6) 100 parts, (b-1) 7.8 parts And 1-pentacontene (C50 α-olefin) (c-4), except that 3.3 parts were used, and the same procedure as in Production Example 7 was carried out, and an inorganic material containing a copolymer (RX-1). A filler dispersant (RA-1) was obtained. (RX-1) had an acid value of 40 and Mn of 75,000.

Comparative production example 2
In Production Example 7, (a-1) 100 parts, (b-1) 24 parts, (c-1) 18.5 parts instead of (a-5) 100 parts, (b-1) 146.1 parts , 1-butene (c-5), except that 63.5 parts were used, the same procedure as in Production Example 7 was carried out, and a dispersant for inorganic filler (RA-2) containing a copolymer (RX-2) was used. ) (RX-2) had an acid value of 270 and Mn of 1,100.

Comparative production example 3
In Production Example 7, instead of (a-1) 100 parts, (b-1) 24 parts, (c-1) 18.5 parts, (a-6) 100 parts, (b-1) 5.5 Except that 5.5 parts of (c-1) was used, the same procedure as in Production Example 7 was carried out, and a dispersant for inorganic filler (RA-3) containing a copolymer (RX-3) was used. Obtained. (RX-3) had an acid value of 28 and Mn of 67,000.

[Inorganic filler-containing polyolefin resin composition, molded product]
Examples 1-21, Comparative Examples 1-8
The obtained dispersant and the following raw materials [polyolefin resin (B), inorganic filler (C)] were each blended for 3 minutes in a Henschel mixer according to the composition (parts) in Table 1, and then vented 2 In an axial extruder, the mixture was melt-kneaded at 180 ° C., 100 rpm, and a residence time of 5 minutes to obtain an inorganic filler-containing polyolefin resin composition. Each polyolefin resin composition was molded at a cylinder temperature of 190 ° C. and a mold temperature of 60 ° C. using an injection molding machine [trade name “PS40E5ASE”, Nissei Plastic Industry Co., Ltd.]. Evaluation was performed according to the evaluation method. The results are shown in Table 1.

<Raw materials>
Polyolefin resin (B)
(B-1): Commercially available polypropylene [trade name “Sun Allomer PL500A”,
Sun Allomer Co., Ltd., Mn 300,000]
(B-2): commercially available polyethylene [trade name “Novatech HJ490”,
Nippon Polyethylene Co., Ltd., Mn 300,000]
(B-3): Commercially available ethylene / propylene copolymer
[Product name "Sun Allomer PB222A"
Sun Aroma Co., Ltd., Mn 350,000]

Inorganic filler (C)
(C-1): Commercially available talc [trade name “LMS-100”, manufactured by Fuji Talc Co., Ltd.,
Volume average particle diameter 6 μm]
(C-2): Commercially available magnesium carbonate [trade name “light calcium carbonate”,
[Omi Chemical Industry Co., Ltd., volume average particle size 4μm]
(C-3): Commercially available magnesium hydroxide [trade name “Sukima 5A”,
Manufactured by Kyowa Chemical Industry Co., Ltd., volume average particle size 1 μm]
(C-4): commercially available alumina [trade name “A-12” manufactured by Showa Denko KK,
Volume average particle diameter 60 μm]

<Evaluation method>
(1) Impact resistance (unit: kJ / m ² )
The Charpy impact value was measured according to ASTM D6110.
(2) Affinity between polyolefin resin (B) and inorganic filler (C) [dispersibility of (C)]
The fracture surface of the test piece after the test of (1) was observed with an electron microscope, and the affinity between (B) and (C) was evaluated according to the following criteria.
◎ No interfacial delamination between (B) / (C) ○ Interfacial delamination between (B) / (C) but very small △ Interfacial delamination is slightly between (B) / (C) × (B) / (C) Interfacial peeling is large between (3) Bending elastic modulus (unit: MPa)
Measured according to ASTM D790.
(4) Deflection temperature under load (unit: ° C)
The deflection temperature under load was measured according to JIS K7191-2.

  From the results of Table 1, the molded product formed by molding the inorganic filler-containing polyolefin resin composition of the present invention is superior in dispersibility of the inorganic filler compared to the comparative one, and extremely excellent in mechanical strength and thermal characteristics. Recognize.

  The polyolefin resin composition containing the inorganic filler of the present invention is excellent in dispersibility of the inorganic filler, and a molded product obtained by molding the composition has excellent mechanical strength and thermal characteristics. It is extremely useful because it can be suitably applied to a wide range of fields such as for conveying materials, for living materials and for building materials.

Claims (12)

  Dispersant for inorganic filler comprising polyolefin (a) and unsaturated (poly) carboxylic acid (anhydride) (b) as constituent units and containing copolymer (X) having an acid value of 50 to 250 mgKOH / g An inorganic filler-containing polyolefin resin composition comprising (A), a polyolefin resin (B), and an inorganic filler (C).   The composition according to claim 1, wherein (b) is an unsaturated dicarboxylic acid (anhydride).   The composition according to claim 1 or 2, further comprising an aliphatic unsaturated hydrocarbon (c) added to the constituent unit of the copolymer (X).   The composition according to any one of claims 1 to 3, wherein (X) is a graft copolymer in which (a) is a trunk and (b) or a (co) polymer of (b) and (c) is a branch. .   (X) is a copolymer obtained by copolymerizing (a) and (b) or (a), (b) and (c) in the presence of a radical initiator (d). The composition in any one of 1-4.   The composition according to any one of claims 1 to 5, wherein (a) has 0.1 to 20 double bonds per 1,000 carbon atoms.   The composition according to any one of claims 1 to 6, wherein (a) is a polyolefin obtained by thermally degrading a polyolefin (a0) having a number average molecular weight of 30,000 to 400,000.   The composition according to any one of claims 1 to 7, wherein the weight ratio of (a) to (b) is 30/70 to 92/8.   The content based on the total weight of (a), (b) and (c) is 20 to 85% for (a), 8 to 45% for (b), and 5 to 65% for (c). The composition in any one of 3-8.   The proportion based on the total weight of (A), (B), and (C) is (A) 0.1 to 15%, (B) 30 to 98%, and (C) 1 to 60%. Item 10. The composition according to any one of Items 1 to 9.   A molded article formed by molding the composition according to claim 1.   A molded article obtained by coating and / or printing the molded article according to claim 11.