JP4855945B2 - PROPYLENE RESIN COMPOSITION, MOLDED BODY AND ELECTRIC WIRE COMPRISING THE COMPOSITION - Google Patents

Description

The present invention relates to a propylene-based resin composition and a molded body obtained from the composition. More specifically, the present invention relates to a propylene-based resin composition having an excellent balance of mechanical strength, flexibility, and scratch resistance, and further relates to a molded body using the propylene-based resin composition.

Propylene-based resins are materials that have better heat resistance, mechanical strength, and scratch resistance than ethylene-based resins (polyethylene-based elastomers), and their molded products are used in a wide range of applications. A molded product obtained from a resin composition comprising general polypropylene and an inorganic filler is also excellent in heat resistance and mechanical strength, but on the other hand, it is inferior in flexibility and impact resistance. For this reason, ethylene-based resins have been mainly used for applications that require characteristics such as flexibility and impact resistance. However, a molded product obtained from an ethylene-based resin has a problem that it is inferior in scratch resistance.

On the other hand, as a molded body composed of a propylene-based resin and an inorganic filler (a flame retardant), an electric wire or a wire harness that requires scratch resistance is known. Patent Document 1 discloses an insulated wire for automobiles using a specific propylene polymer. However, the molded body used in Patent Document 1 is excellent in flexibility and impact resistance, but has insufficient scratch resistance.
JP 2003-313377 A

An object of the present invention is to provide a propylene-based resin composition having an excellent balance of mechanical strength, flexibility, and scratch resistance. Moreover, the objective of this invention is providing the electric wire which has the molded object which consists of this composition, the insulator which uses this composition, and / or a sheath.

As a result of intensive studies to solve the above problems, the present inventors have used a specific propylene polymer in a specific amount, so that the uptake of an inorganic filler, that is, in the resin composition. Propylene-based inorganic filler with good dispersibility, excellent adhesion at the interface between the resin component and filler, and better balance of mechanical strength, flexibility, and scratch resistance than conventional compositions It has been found that a resin composition can be obtained. Furthermore, it discovered that the molded object excellent in scratch resistance was obtained by using such a specific propylene-type resin composition, and completed this invention.

  That is, the propylene-based resin composition of the present invention comprises 5-84.5% by mass of the differential scanning calorific value of the propylene-based polymer (A) having a melting point of 120 to 170 ° C. measured by a differential scanning calorimeter (DSC). The melting point measured by analysis (DSC) is less than 120 ° C. or the melting point is not observed, 0.5 to 4.5% by mass of the propylene polymer (B), the ethylene elastomer (C-1) and the styrene elastomer ( A total of 0 to 40% by mass of one or more elastomers (C) selected from C-2) and 15 to 80% by mass of an inorganic filler (D) (where (A), (B), The total amount of the components (C) and (D) is 100% by mass.)

The propylene polymer (B) is preferably a propylene / α-olefin random copolymer (B-1) having 4 to 20 carbon atoms that satisfies the following (a) and (b).
(A) The molecular weight distribution (Mw / Mn) measured by gel permeation chromatography (GPC) is 1 to 3,
(B) the melting point Tm (° C.) and the comonomer constituent unit content M (mol%) determined by ¹³ C-NMR spectrum measurement,
146 exp (−0.022 M) ≧ Tm ≧ 125 exp (−0.032 M) (1)
(Where Tm is less than 120 ° C, preferably less than 100 ° C).

The propylene polymer (B) is preferably a propylene / ethylene / α-olefin random copolymer (B-2) having 4 to 20 carbon atoms satisfying the following (m) and (n). .
(M) The molecular weight distribution (Mw / Mn) measured by gel permeation chromatography (GPC) is 1 to 3,
(N) 40 to 85 mol% of propylene-derived structural units, 5 to 30 mol% of structural units derived from ethylene, and 5 to 30 mol% of structural units derived from α-olefins having 4 to 20 carbon atoms ( Here, the total of the structural unit derived from propylene, the structural unit derived from ethylene, and the structural unit derived from an α-olefin having 4 to 20 carbon atoms is 100 mol%).

The inorganic filler (D) is preferably at least one selected from metal hydroxides, metal carbonates and metal oxides.
The propylene resin composition of the present invention is one or more selected from propylene polymer (A), propylene polymer (B), ethylene elastomer (C-1) and styrene elastomer (C-2). The graft amount of the vinyl compound having a polar group is 0.01 when the mass of the graft-modified polymer is 100 mass% with respect to a total of 100 mass parts of the elastomer (C) and the inorganic filler (D). It is preferable that 0.1-30 mass parts of graft-modified polymers (E) which are 10 mass% are included.

The molded article of the present invention is characterized by comprising the propylene-based resin composition as described above.
The molded body is preferably an electric wire insulator or electric wire sheath.
The electric wire of the present invention is an electric wire having an insulator using the propylene resin composition as described above and / or a sheath using the propylene resin composition as described above.

  The electric wire is preferably an automobile electric wire or an equipment electric wire.

The propylene-based resin composition of the present invention contains an inorganic filler in a high proportion and is excellent in the balance of mechanical strength, flexibility, and scratch resistance.
Furthermore, the propylene-based resin composition of the present invention has flame retardancy and can be suitably used for a molded article having excellent balance of mechanical strength, flexibility, and scratch resistance, particularly an electric wire.

Hereinafter, the present invention will be specifically described.
<Propylene polymer (A)>
Examples of the propylene polymer (A) used in the present invention include a propylene homopolymer or a copolymer of propylene and at least one olefin having 2 to 20 carbon atoms other than propylene. . Here, as olefins having 2 to 20 carbon atoms other than propylene, ethylene, 1-butene, 1-pentene, 1-hexene, 4-methyl-1-pentene, 1-octene, 1-decene, 1-decene, Examples include dodecene, 1-tetradecene, 1-hexadecene, 1-octadecene, 1-eicocene, and the like, and ethylene or an α-olefin having 4 to 10 carbon atoms is preferable. These olefins may form a random copolymer with propylene or a block copolymer.
The structural unit derived from these olefins may be contained in the entire structural unit of the propylene polymer (A) in a proportion of 35 mol% or less, preferably 30 mol% or less.

In the propylene polymer (A), the melt flow rate (MFR) measured at a temperature of 230 ° C. and a load of 2.16 kg in accordance with ASTM D 1238 is usually 0.01 to 1000 g / 10 minutes, preferably Is from 0.05 to 100 g / 10 min, more preferably from 0.1 to 50 g / 10 min.
About the propylene polymer (A) used for this invention, melting | fusing point measured with a differential scanning calorimeter (DSC) is 120-170 degreeC, Preferably it is 125-165 degreeC.
The propylene polymer (A) may have either an isotactic structure or a syndiotactic structure, but preferably has an isotactic structure from the viewpoint of heat resistance.
Moreover, a some propylene polymer (A) can be used together as needed, for example, 2 or more types of components from which melting | fusing point and rigidity differ can also be used.

  In addition, as the propylene polymer (A), homopolypropylene having excellent heat resistance (a known one in which the copolymerization component other than propylene is usually 3 mol% or less), a block having a good balance between heat resistance and impact resistance. Polypropylene (usually a known material having an n-decane eluting component of 3 to 30% by mass), or random polypropylene (usually a melting peak temperature measured by a differential scanning calorimeter (DSC)) excellent in balance between flexibility and transparency May be selected and used in order to obtain the desired physical properties, or these may be used in combination. .

  Such a propylene polymer (A) includes, for example, a solid catalyst component containing magnesium, titanium, halogen and an electron donor as essential components, a Ziegler catalyst system comprising an organoaluminum compound and an electron donor, or a metallocene compound. It can be produced by polymerizing propylene or copolymerizing propylene and other olefins using a metallocene catalyst system used as a component of the catalyst.

<Propylene polymer (B)>
Examples of the propylene polymer (B) used in the present invention include a propylene homopolymer or a copolymer of propylene and at least one of olefins having 2 to 20 carbon atoms other than propylene. it can. Here, examples of the olefin having 2 to 20 carbon atoms other than propylene include the same as those in the case of the propylene polymer (A), and the preferred range is also the same. These olefins may form a random copolymer with propylene or a block copolymer.

  The propylene-based polymer (B) contains a propylene-derived structural unit usually in an amount of 40 to 100 mol%, preferably 40 to 99 mol%, more preferably 40 to 92 mol%, still more preferably 50 to 90 mol%, The structural unit derived from an α-olefin having 2 to 20 carbon atoms (excluding propylene) used as a comonomer is usually 0 to 60 mol%, preferably 1 to 60 mol%, more preferably 8 to 60 mol%. More preferably, it is 10 to 50 mol% (here, the total of propylene and olefins having 2 to 20 carbon atoms is 100 mol%).

  In the propylene-based polymer (B) used in the present invention, the melt flow rate (MFR, ASTM D1238, temperature 230 ° C., under 2.16 kg load) is usually 0.1 to 50 (g / 10 min). The propylene-based polymer (B) has a melting point measured by differential scanning calorimetry (DSC) of less than 120 ° C. or no melting point is observed, and preferably the melting point is 100 ° C. or less. Or no melting point is observed. Here, that the melting point is not observed means that a crystal melting peak having a heat of crystal melting of 1 J / g or more is not observed in the range of −150 to 200 ° C. The measurement conditions are as described in the examples.

The propylene-based polymer (B) has an intrinsic viscosity [η] measured in decalin at a temperature of 135 ° C. in the range of usually 0.01 to 10 dl / g, preferably 0.05 to 10 dl / g.
The propylene-based polymer (B) preferably has a triad tacticity (mm fraction) measured by ¹³ C-NMR of 85% or more, more preferably 85 to 97.5%, still more preferably 87 to 97%. Particularly preferably, it is in the range of 90 to 97%. When the triad tacticity (mm fraction) is in this range, the balance between flexibility and mechanical strength is particularly excellent, which is suitable for the present invention. The mm fraction can be measured by the method described in International Publication No. 2004-087775 pamphlet, page 21, line 7 to page 26, line 6.

  The production method of the propylene-based polymer (B) is not particularly limited, but a known catalyst capable of stereoregular polymerization of an olefin with an isotactic structure or a syndiotactic structure, for example, a solid titanium component and an organometallic compound is mainly used. It can be produced by polymerizing propylene or copolymerizing propylene and other olefins in the presence of a component catalyst or a metallocene catalyst using a metallocene compound as one component of the catalyst. Further, it can be produced by polymerizing propylene using a known catalyst capable of polymerizing olefins with an atactic structure, or copolymerizing propylene and other olefins. Preferably, as described later, it is obtained by copolymerizing propylene and an olefin having 2 to 20 carbon atoms (excluding propylene) in the presence of a metallocene catalyst.

  Specific examples of the propylene-based polymer (B) having the above-described characteristics include propylene / α-olefin random copolymer (B-1) having 4 to 20 carbon atoms, and propylene / An α-olefin random copolymer (B-2) having 4 to 20 ethylene atoms can be exemplified.

  By using a propylene / α-olefin random copolymer (B-1) having 4 to 20 carbon atoms, for example, compatibility with a polypropylene crystal component contained in the propylene polymer (A) is exhibited, and mechanical strength is exhibited. A propylene-based resin composition having excellent elongation at break and scratch resistance can be obtained.

  Further, the α-olefin random copolymer (B-2) having 4 to 20 carbon atoms and propylene / ethylene / carbon atom is the same as the α-olefin random copolymer (B-1) having 4 to 20 carbon atoms and propylene. In addition, it has compatibility with the crystalline component of polypropylene, and by using this propylene / ethylene / α-olefin random copolymer (B-2) having 4 to 20 carbon atoms, flexibility and scratch resistance are obtained. A propylene-based resin composition that is more excellent in stickiness can be obtained.

  The propylene / C4-20 α-olefin random copolymer (B-1) and propylene / ethylene / C4-20 α-olefin random copolymer preferably used in the present invention The combination (B-2) will be described in detail.

[Propylene / C4-C20 α-olefin random copolymer (B-1)]
The propylene / α-olefin random copolymer (B-1) having 4 to 20 carbon atoms preferably used in the present invention is at least one of propylene and an α-olefin having 4 to 20 carbon atoms other than propylene. And a copolymer thereof. Here, examples of the α-olefin having 4 to 20 carbon atoms other than propylene include 1-butene, 1-pentene, 1-hexene, 4-methyl-1-pentene, 1-octene, 1-decene, 1-decene, Examples include dodecene, 1-tetradecene, 1-hexadecene, 1-octadecene and 1-eicocene. The α-olefin random copolymer (B-1) having 4 to 20 propylene / carbon atoms satisfies the following (a) and (b).
(A) The molecular weight distribution (Mw / Mn) measured by gel permeation chromatography (GPC) is 1 to 3,
(B) the melting point Tm (° C.) and the comonomer constituent unit content M (mol%) determined by ¹³ C-NMR spectrum measurement,
146 exp (−0.022 M) ≧ Tm ≧ 125 exp (−0.032 M) (1)
(Where Tm is less than 120 ° C., preferably 100 ° C. or less).

  The melting point Tm of the propylene / C4-C20 α-olefin random copolymer (B-1) is measured by DSC as follows. The sample is packed in an aluminum pan, heated to 200 ° C. at 100 ° C./min, held at 200 ° C. for 5 minutes, then cooled to −150 ° C. at 10 ° C./min, and then 200 ° C. at 10 ° C./min. The temperature of the endothermic peak observed when the temperature is raised to ° C. is the melting point Tm. This melting point Tm is usually less than 120 ° C, preferably 100 ° C or less, more preferably in the range of 40 to 95 ° C, and still more preferably in the range of 50 to 90 ° C. When the melting point Tm is within this range, a molded article having an excellent balance between flexibility and strength can be obtained. Moreover, since the stickiness of the surface of a molded article is suppressed, the molded object using the composition of this invention has the advantage that it is easy to construct.

In the propylene / α-olefin random copolymer (B-1) having 4 to 20 carbon atoms,
(C) The degree of crystallinity measured by X-ray diffraction is preferably 40% or less, more preferably 35% or less.
In the propylene / α-olefin random copolymer (B-1) having 4 to 20 carbon atoms, the content of the structural unit derived from the α-olefin having 4 to 20 carbon atoms is preferably 5 to 50 mol%, more Preferably it is 10-35 mol%. In particular, 1-butene is preferably used as the α-olefin having 4 to 20 carbon atoms.
Such a propylene polymer can be obtained by, for example, a method described in International Publication No. 2004/87775 pamphlet.

[Propylene / ethylene / α-olefin random copolymer having 4 to 20 carbon atoms (B-2)]
The α-olefin random copolymer (B-2) of propylene / ethylene / carbon atoms 4 to 20 preferably used in the present invention is α-olefin having 4 to 20 carbon atoms other than propylene, ethylene and propylene. Mention may be made of copolymers with at least one olefin. Here, examples of the α-olefin having 4 to 20 carbon atoms other than propylene include those similar to the case of the α-olefin random copolymer (B-1) having 4 to 20 carbon atoms. .
The α-olefin random copolymer (B-2) having 4 to 20 carbon atoms and propylene / ethylene / carbon atoms satisfies the following (m) and (n).
(M) The molecular weight distribution (Mw / Mn) measured by gel permeation chromatography (GPC) is 1 to 3,
(N) 40 to 85 mol% of propylene-derived structural units, 5 to 30 mol% of structural units derived from ethylene, and 5 to 30 mol% of structural units derived from α-olefins having 4 to 20 carbon atoms (here The total of the structural unit derived from propylene, the structural unit derived from ethylene, and the structural unit derived from an α-olefin having 4 to 20 carbon atoms is 100 mol%, and the structural unit derived from ethylene and the number of carbon atoms. The total of 4 to 20 α-olefin-derived structural units is preferably 60 to 15 mol%).

In the propylene / ethylene / α-olefin random copolymer (B-2) having 4 to 20 carbon atoms, it is more preferable to satisfy at least one of the following (o) and (p), more preferably both. It is desirable.
(O) Shore A hardness is 30-80, preferably 35-60.
(P) The degree of crystallinity measured by X-ray diffraction is 20% or less, preferably 10% or less.

  Further, the melting point Tm measured by DSC of the propylene / ethylene / α-olefin random copolymer (B-2) having 4 to 20 carbon atoms is preferably 50 ° C. or lower, or no melting point is observed. desirable. More preferably, no melting point is observed. Melting | fusing point can be measured by the same method as the said copolymer (B-1).

The propylene component and the amount of other comonomer components are more specifically described. The constituent unit derived from propylene is preferably 60 to 82 mol%, more preferably 61 to 75 mol%, and the constituent unit derived from ethylene is preferably 8 to 15. It is desirable to include a constituent unit derived from a mol%, more preferably 10 to 14 mol%, and an α-olefin having 4 to 20 carbon atoms, preferably in an amount of 10 to 25 mol%, more preferably 15 to 25 mol%. . In particular, 1-butene is preferably used as the α-olefin having 4 to 20 carbon atoms.
Such a propylene / ethylene / α-olefin random copolymer (B-2) can be obtained by, for example, a method described in International Publication No. 2004/87775.

  In the present invention, by using a propylene / ethylene / [alpha] -olefin random copolymer (B-2) having 4 to 20 carbon atoms, the molded article has improved flexibility and low embrittlement temperature at low temperature. Is obtained. For example, when this molded body is an electric wire, it has an advantage that the electric wire coating is not easily broken even when exposed to low temperatures.

<Elastomer (C)>
The elastomer (C) used in the present invention comprises an ethylene-based elastomer (C-1) having a structural unit derived from ethylene of 61 mol% or more based on the total structural unit, and a structural unit derived from styrene as the total structural unit. It is 1 or more types of elastomers chosen from the styrene-type elastomer (C-2) which has 5 to 70 mass% with respect to.

  The elastomer (C) is not particularly limited as long as the Shore A hardness is in the range of 30 to 90. For example, styrene / butadiene rubber and its hydride, ethylene / α-olefin random copolymer, ethylene / vinyl acetate copolymer. Examples thereof include a polymer, an ethylene / acrylic acid copolymer, and an ethylene / methyl methacrylate copolymer.

As the ethylene elastomer (C-1), an ethylene / α-olefin random copolymer is preferably used. The ethylene / α-olefin random copolymer is usually a copolymer of ethylene and an α-olefin having 3 to 20 carbon atoms, preferably a copolymer of ethylene and an α-olefin having 3 to 10 carbon atoms. Although it means a coalescence, it is preferable that the following (x) and (y) are satisfied.
(X) Density (ASTM 1505, temperature 23 ° C.) is 0.850 to 0.910 g / cm ³ , preferably 0.860 to 0.905 g / cm ³ , more preferably 0.865 to 0.895 g / cm ^3. And
(Y) The melt flow rate (MFR, temperature 190 ° C., under a load of 2.16 kg) is 0.1 to 150 g / 10 minutes, preferably 0.3 to 100 g / 10 minutes.

  The ethylene / α-olefin random copolymer has a crystallinity measured by an X-ray diffraction method of usually 40% or less, preferably 0 to 39%, more preferably 0 to 35%.

Examples of the α-olefin having 3 to 20 carbon atoms used as a comonomer include propylene, 1-butene, 1-pentene, 1-hexene, 4-methyl-1-pentene, 1-octene, 1-decene, 1-dodecene is mentioned. These may be used alone or in combination of two or more. Of these, propylene, 1-butene, 1-hexene and 1-octene are preferable.
As alpha-olefin content in the said copolymer, it is 3-39 mol% normally, Preferably it is 5-30 mol%, More preferably, it is 5-25 mol%.
Moreover, you may contain small amounts of other conomomers, for example, dienes such as 1,6-hexadiene and 1,8-octadiene, and cyclic olefins such as cyclopentene, if necessary.
The molecular structure of the copolymer may be linear or branched having long or short side chains.
It is also possible to use a mixture of a plurality of different ethylene / α-olefin random copolymers.
The method for obtaining such an ethylene / α-olefin random copolymer is not particularly limited, and examples thereof include a method of producing by a conventionally known method using a vanadium catalyst, a titanium catalyst, a metallocene catalyst, or the like. In particular, a copolymer produced using a metallocene catalyst usually has a molecular weight distribution (Mw / Mn) of 3 or less and can be preferably used in the present invention.

  The styrene elastomer (C-2) is a polybutadiene block segment, a hydrogenated diene polymer comprising a styrene compound (including styrene; the same applies hereinafter) / butadiene copolymer block segment, a polyisoprene block segment, A hydrogenated diene polymer comprising a styrene compound / isoprene copolymer block segment, a block copolymer comprising a polymer block mainly comprising a styrene compound and a polymer block mainly comprising a conjugated diene compound, A hydrogenated block copolymer comprising a polymer block mainly composed of a styrene compound and a polymer block mainly composed of a conjugated diene compound, and a random copolymer of a styrene compound and a conjugated diene compound Examples include hydrogenated substances, but these known ones Without limitation can be used. Such styrenic elastomers may be used alone or in combination of two or more.

Moreover, in this invention, you may use together an ethylene-type elastomer (C-1) and a styrene-type elastomer (C-2).
<Inorganic filler (D)>
There is no restriction | limiting in particular as an inorganic type filler (D) used for this invention, For example, inorganic compounds, such as a metal compound; glass, ceramic, talc, mica, etc. are used widely. Of these, metal hydroxides, metal carbonates (carbonates), and metal oxides are preferably used. In the present invention, the inorganic filler (D) may be used alone or in combination of two or more. For example, aluminum hydroxide, magnesium hydroxide, etc. are used as the metal hydroxide, calcium carbonate, precipitated calcium carbonate, heavy calcium carbonate, magnesium carbonate, etc. are used as the metal carbonate, and zinc oxide is used as the metal oxide. , Zinc white, magnesium oxide, antimony oxide and the like.

Here, the inorganic filler is preferably one that functions as a flame retardant, and for example, one or more inorganic fillers selected from metal hydroxides and metal oxides are preferable.
As an average particle diameter of an inorganic type filler (D), it is 0.1-20 micrometers normally, Preferably it is 0.5-15 micrometers. Here, the average particle diameter is a value determined by a laser method.
The inorganic filler (D) used in the present invention may be surface-treated with a fatty acid such as stearic acid or oleic acid, an organic silane, or the like, and the fine particles having the above average particle diameter are agglomerated. A collection may be formed.

<Graft modified polymer (E)>
Examples of the polymer used as a raw material for the graft-modified polymer (E) include polymers of one or more olefins, styrene block copolymers, and the like, particularly ethylene polymers, propylene polymers, Preferable examples include styrenic block copolymers. Examples of the olefin include olefins having 2 to 20 carbon atoms.

  As the ethylene polymer, polyethylene and ethylene / α-olefin copolymer are preferable. Among the ethylene / α-olefin copolymers, a copolymer of ethylene and an α-olefin having 3 to 10 carbon atoms is preferable. Specific examples of the α-olefin having 3 to 10 carbon atoms include propylene, 1-butene, 1-pentene, 1-hexene, 3-methyl-1-butene, 3-methyl-1-pentene, 3 -Ethyl-1-pentene, 4-methyl-1-pentene, 4-methyl-1-hexene, 4,4-dimethyl-1-pentene, 4-ethyl-1-hexene, 1-octene, 3-ethyl-1 -Hexene, 1-octene, 1-decene and the like. These may be used alone or in combination of two or more. Among these, it is particularly preferable to use at least one of propylene, 1-butene, 1-hexene and 1-octene.

  The content of each structural unit in the ethylene-based copolymer is such that the content of the structural unit derived from ethylene is 75 to 95 mol%, and is at least one selected from α-olefins having 3 to 10 carbon atoms. The content of structural units derived from the compound is preferably 5 to 20 mol%.

The ethylene / α-olefin copolymer is
(i) the density is 0.855 to 0.910 g / cm ³ , preferably 0.857 to 0.890 g / cm ³ ;
(ii) Melt flow rate (MFR, temperature 190 ° C., under 2.16 kg load) is in the range of 0.1 to 100 g / 10 minutes, preferably 0.1 to 20 g / 10 minutes,
(iii) The molecular weight distribution index (Mw / Mn) evaluated by GPC method is in the range of 1.5 to 3.5, preferably 1.5 to 3.0, more preferably 1.8 to 2.5. Yes,
(iv) The B value determined from the ¹³ C-NMR spectrum and the following formula is 0.9 to 1.5, preferably 1.0 to 1.2.

B value = [POE] / (2 · [PE] [PO])
(Wherein [PE] is the molar fraction of structural units derived from ethylene in the copolymer, and [PO] is the content of structural units derived from α-olefins in the copolymer) ("POE" is the ratio of the number of ethylene / α-olefin chains to the total dyad chains in the copolymer)
The graft-modified polymer used in the present invention is obtained, for example, by graft-modifying an α-olefin polymer, a styrene block copolymer or the like with a vinyl compound having a polar group. Examples of the vinyl compound include vinyl compounds having oxygen-containing groups such as acids, acid anhydrides, esters, alcohols, epoxies, and ethers, vinyl compounds having nitrogen-containing groups such as isocyanate and amide, and silicon-containing groups such as vinylsilane. A vinyl compound etc. are mentioned.

Among these, a vinyl compound having an oxygen-containing group is preferable, and specifically, an unsaturated epoxy monomer, an unsaturated carboxylic acid, and a derivative thereof are preferable.
Examples of the unsaturated epoxy monomer include unsaturated glycidyl ether and unsaturated glycidyl ester (for example, glycidyl methacrylate).
Examples of the unsaturated carboxylic acid include acrylic acid, maleic acid, fumaric acid, tetrahydrophthalic acid, itaconic acid, citraconic acid, crotonic acid, isocrotonic acid, nadic acid ^TM (endocis-bicyclo [2,2,1] hept-5 -Ene-2,3-dicarboxylic acid) and the like.

  Examples of the unsaturated carboxylic acid derivative include an acid halide compound, an amide compound, an imide compound, an acid anhydride, and an ester compound of the unsaturated carboxylic acid. Specific examples include maleyl chloride, maleimide, maleic anhydride, citraconic anhydride, monomethyl maleate, dimethyl maleate, glycidyl maleate, and the like.

Of these, unsaturated dicarboxylic acids and acid anhydrides thereof are more preferable, and maleic acid, nadic acid ^TM and acid anhydrides thereof are particularly preferably used.
The grafting position of the unsaturated carboxylic acid or derivative thereof grafted to the unmodified ethylene copolymer is not particularly limited, and the unsaturated carboxylic acid or derivative thereof is attached to any carbon atom of the ethylene polymer. It only has to be joined.

The graft-modified polymer (E) as described above can be prepared using various conventionally known methods, for example, the following methods.
(1) A method in which the unmodified polymer is melted with an extruder or the like, and an unsaturated carboxylic acid or the like is added for graft copolymerization.
(2) A method in which the unmodified polymer is dissolved in a solvent and an unsaturated carboxylic acid or the like is added to perform graft copolymerization.
In any method, it is preferable to perform the graft reaction in the presence of a radical initiator in order to efficiently graft copolymerize the above-mentioned unsaturated monomer such as unsaturated carboxylic acid.

Examples of the radical initiator include organic peroxides and azo compounds.
Examples of the organic peroxide include benzoyl peroxide, dichlorobenzoyl peroxide, and dicumyl peroxide. Examples of the azo compound include azobisisobutylnitrile and dimethylazoisobutyrate.
Specific examples of such radical initiators include dicumyl peroxide, di-tert-butyl peroxide, 2,5-dimethyl-2,5-di (tert-butylperoxy) hexyne-3, 2,5- Dialkyl peroxides such as dimethyl-2,5-di (tert-butylperoxy) hexane and 1,4-bis (tert-butylperoxyisopropyl) benzene are preferably used.

These radical initiators are usually 0.001 to 1 part by weight, preferably 0.003 to 0.5 parts by weight, and more preferably 0.05 to 0.3 parts by weight with respect to 100 parts by weight of the unmodified polymer. Used in parts by mass.
The reaction temperature in the graft reaction using the radical initiator as described above or in the graft reaction performed without using the radical initiator is usually set in the range of 60 to 350 ° C, preferably 150 to 300 ° C.

  The graft amount of the vinyl compound having a polar group in the graft-modified polymer (E) thus obtained is usually 0.01 to 10% by mass when the mass of the graft-modified polymer is 100% by mass, Preferably it is 0.05-5 mass%. In the present invention, by using the graft-modified polymer (E) as described above, in particular, the interaction between the inorganic filler and the resin component constituting the propylene-based resin composition is enhanced, and the mechanical strength, A propylene-based resin composition having an excellent balance between flexibility and scratch resistance can be obtained, and a molded product obtained by molding the resin composition is similarly balanced with mechanical strength, flexibility, and scratch resistance. Excellent.

<Propylene-based resin composition and molded article>
The propylene-based resin composition of the present invention comprises 5-84.5% by mass of the propylene-based polymer (A), 0.5-4.5% by mass of the propylene-based polymer (B), and 0% of the elastomer (C). -40 mass%, and inorganic filler (D) 15-80 mass% (Here, the total amount of (A), (B), (C), and (D) component is 100 mass%) .)

  In the case of using an α-olefin random copolymer (B-1) having 4 to 20 carbon atoms as the propylene polymer (B), the propylene resin composition is a propylene polymer (A). 5) to 84.5% by mass, preferably 5 to 70% by mass, more preferably 5 to 60% by mass, still more preferably 5 to 50% by mass, particularly preferably 10 to 40% by mass, and the number of propylene / carbon atoms. 4 to 20 α-olefin random copolymer (B-1) is 0.5 to 4.5% by mass, preferably 0.5 to 4.0% by mass, and elastomer (C) is 0 to 40% by mass, Preferably 0 to 30% by mass, more preferably 0 to 25% by mass, still more preferably 5 to 20% by mass, particularly preferably 5 to 15% by mass, and 15 to 80% by mass of the inorganic filler (D). , Preferably 20-70 quality Desirably, it is desirable to contain 30% to 70% by weight, more preferably 30% to 60% by weight, particularly preferably 35% to 60% by weight (where (A), (B), (C), and (D) The total amount of component is 100 mass%.).

  Further, when the propylene-ethylene / alpha-olefin random copolymer (B-2) having 4 to 20 carbon atoms is used as the propylene-based polymer (B), the propylene-based resin composition is a propylene-based polymer. 5-84.5 mass% of a polymer (A), Preferably 5-70 mass%, More preferably, it is 5-60 mass%, More preferably, it is 5-50 mass%, Most preferably, it is 10-40 mass%, Propylene 1-butene random copolymer (B-2) is 0.5 to 4.5% by mass, preferably 0.5 to 4.0% by mass, and elastomer (C) is 0 to 40% by mass, preferably 0 To 30% by mass, more preferably 0 to 25% by mass, further preferably 5 to 20% by mass, particularly preferably 5 to 15% by mass, and 15 to 80% by mass of the inorganic filler (D), preferably 20-70% by mass Preferably 30 to 70% by mass, more preferably 30 to 60% by mass, and particularly preferably 35 to 60% by mass (wherein (A), (B), (C), and (D) components are included. Is 100% by mass.).

  Further, when the graft-modified polymer (E) is used, and when the α-olefin random copolymer (B-1) having 4 to 20 carbon atoms is used, the propylene-based resin composition is 5-84.5 mass% of a propylene polymer (A), Preferably it is 5-70 mass%, More preferably, it is 5-60 mass%, More preferably, it is 5-50 mass%, Most preferably, it is 10-40 mass%. , 0.5 to 4.5 mass%, preferably 0.5 to 4.0 mass% of the α-olefin random copolymer (B-1) of propylene / carbon atoms 4 to 20 and elastomer (C). 0 to 40% by mass, preferably 0 to 30% by mass, more preferably 0 to 25% by mass, still more preferably 0 to 20% by mass, particularly preferably 0 to 15% by mass, and the inorganic filler (D) 15-80% by mass, good It is desirable to contain 20 to 70% by mass, more preferably 30 to 70% by mass, further preferably 30 to 60% by mass, particularly preferably 35 to 60% by mass (where (A) and (B) The total amount of components (C) and (D) is 100% by mass.) In this case, the blended amount of the graft-modified polymer (E) is 0.1-30 with respect to 100 parts by mass of the total amount of the components (A), (B), (C), and (D). It is 0.1-10 mass parts, More preferably, it is 0.1-8 mass parts. When the blended amount of the graft-modified polymer (E) is within this range, the effect of improving the scratch resistance is remarkable and the fluidity of the composition is excellent, which is preferable.

  Further, when the graft-modified polymer (E) is used, the propylene / α-olefin random copolymer (B) is a propylene / ethylene / α-olefin random copolymer having 4 to 20 carbon atoms (B- In the case of using 2), the propylene-based resin composition contains 5-84.5% by mass of the propylene-based polymer (A), preferably 5-70% by mass, more preferably 5-60% by mass, Preferably 5 to 50% by mass, particularly preferably 10 to 40% by mass, and 0.5 to 4.5% by mass of propylene / ethylene / α-olefin random copolymer (B-2) having 4 to 20 carbon atoms. The elastomer (C) is preferably 0 to 40% by mass, preferably 0 to 30% by mass, more preferably 0 to 25% by mass, still more preferably 0 to 20% by mass, Especially good Preferably, 0 to 15% by mass, and 15 to 80% by mass, preferably 20 to 70% by mass, more preferably 30 to 70% by mass, and further preferably 30 to 60% by mass of the inorganic filler (D). In particular, it is desirable to contain 35 to 60% by mass (here, the total amount of the components (A), (B), (C), and (D) is 100% by mass). In this case, the blended amount of the graft-modified polymer (E) is usually 0.1 to 100 parts by mass of the total amount of the components (A), (B), (C), and (D). 30 parts by mass, preferably 0.1 to 10 parts by mass, more preferably 0.1 to 8 parts by mass. When the blended amount of the graft-modified polymer (E) is within this range, the effect of improving the scratch resistance is remarkable and the fluidity of the composition is excellent, which is preferable.

  The propylene-based resin composition of the present invention includes other synthetic resins, other rubbers, antioxidants, heat-resistant stabilizers, weather-resistant stabilizers, slips as necessary, as long as the object of the present invention is not impaired. Additives such as an agent, an antiblocking agent, a crystal nucleating agent, a pigment, a hydrochloric acid absorbent, and a copper damage inhibitor may be included. The addition amount of such other synthetic resins, other rubbers, additives and the like is not particularly limited as long as the object of the present invention is not impaired. For example, in the entire propylene-based resin composition, (A), The aspect contained so that the sum total of (B), (C) and (D) component may be 60-100 mass%, Preferably it is 80 mass%-100 mass% is preferable. The balance is the other synthetic resin, other rubber, additive, graft-modified polymer (E) and the like.

  The propylene-based resin composition of the present invention can be produced using a conventionally known method. For example, after mixing each component as described above using a Henschel mixer, a tumbler blender, etc., it can be manufactured by melt-kneading using an extruder or the like.

<Molded body>
The molded product of the present invention is composed of the propylene-based resin composition as described above. The molded body of the present invention can be melt-molded into various shapes using the propylene-based resin composition by a conventionally known melt molding method. Examples of conventionally known melt molding methods include extrusion molding, rotational molding, calendar molding, injection molding, compression molding, transfer molding, powder molding, blow molding, and vacuum molding.

The molded body may be a complex with a molded body made of other materials, for example, a laminated body.
Moreover, since the molded body has an excellent balance of mechanical strength, flexibility, and scratch resistance, it can be suitably used for, for example, wire coating applications such as a wire insulator and a wire sheath. It is possible to improve the scratch resistance of a molded body such as an electric wire having a crack.
Moreover, the coating layers such as the electric wire insulator and the electric wire sheath are formed around the electric wire by a conventionally known method, for example, a method such as extrusion molding.

The electric wire of the present invention has an insulator using the propylene resin composition as described above and / or a sheath using the propylene resin composition as described above. In particular, the electric wires are preferably automobile electric wires and device electric wires.
Moreover, the above propylene-type resin composition is used suitably also for building materials etc.

  EXAMPLES Hereinafter, although this invention is demonstrated further more concretely based on an Example, this invention is not limited to these Examples.

<Ingredients (A) to (E)>
(A) Isotactic homopolypropylene (h-PP) (Tm: 165 ° C., MFR (temperature 230 ° C.); 0.6 g / 10, produced by the method described in the pamphlet of the propylene-based polymer international publication 2004/87775 Min) was used.
(B) Propylene polymer (B-1) Propylene / 1-butene copolymer (PBR)
Propylene / 1-butene copolymer (MFR (temperature 230 ° C.); 7 g / 10 min, Tm; 75 ° C., 1-butene content; 26 mol%, produced by the method described in WO 2004/87775 pamphlet Mw / Mn; 2.1, crystallinity (WAXD method); 28%).
(B-2) Propylene / ethylene / 1-butene copolymer (PBER)
Propylene / ethylene / 1-butene random copolymer (MFR (temperature 230 ° C.); 8.5 g / 10 min, Tm; not observed, ethylene content) produced by the method described in the pamphlet of International Publication No. 2004/87775. 14 mol%, 1-butene content: 20 mol%, Mw / Mn; 2.0, Shore A hardness: 38, crystallinity (WAXD method): 5% or less, mm value: 90% were used.

(C) Elastomer (C-1) Styrene elastomer (SEBS)
SEBS (trade name, G1650) manufactured by Kraton Polymer Co., Ltd. was used.
(C-2) Ethylene / 1-butene copolymer (EBR)
An ethylene / 1-butene copolymer (density: 870 kg / m ³ , Tm: 53 ° C., MFR (230 ° C.); 7.0 g / 10 min, Mw / Mn; 2.1) was used.
(D) Inorganic filler magnesium hydroxide (Mg (OH) ₂ )
Kyowa Chemical Co., Ltd. (Mg (OH) ₂ ) (trade name, Kisuma 5A) was used.

(E) Graft-modified polymer The following ethylene / 1-butene copolymer (E-1) produced using a metallocene catalyst was used to graft maleic anhydride graft-modified ethylene / 1-butene copolymer (E-2). ) Was manufactured.
(E-1) Ethylene / 1-butene copolymer (EBR)
Ethylene / 1-butene copolymer (density: 885 kg / m ³ , MFR (190 ° C.); 0.5 g / 10 min, Mw / Mn; 2.1, B value: 1.05)
(E-2) Graft-modified ethylene / 1-butene copolymer (graft-modified EBR)
10 kg of the above ethylene / 1-butene copolymer (E-1) was blended in a Henschel mixer with a solution of 50 g of maleic anhydride and 3 g of di-tert-butyl peroxide in 50 g of acetone.

  Next, the obtained blend was introduced from a hopper of a single screw extruder having a screw diameter of 40 mmφ and L / D = 26, and extruded into a strand at a resin temperature of 260 ° C. and an extrusion rate of 6 kg / hour. Subsequently, after cooling with water, pelletization was performed to obtain a maleic anhydride graft-modified ethylene / 1-butene copolymer (E-2).

  From the obtained graft-modified ethylene / 1-butene copolymer (E-2), unreacted maleic anhydride was extracted with acetone, and then the amount of maleic anhydride grafted in the copolymer was measured. Was 0.43% by mass.

<Measuring method of physical properties of each component>
The physical property values of the above components were measured as follows.
(1) Comonomer (ethylene, 1-butene) content and mmmm (stereoregularity, pentad isotacticity)
^It was determined by analysis of ¹³ C-NMR spectrum.
(2) Melt flow rate (MFR)
According to ASTM D-1238, the temperature was measured at 190 ° C. or 230 ° C. under a load of 2.16 kg.
(3) Melting point (Tm)
An exothermic / endothermic curve of DSC was determined, and the temperature at the apex of the melting peak where ΔH during temperature increase was 1 J / g or more was defined as Tm.
The sample is packed in an aluminum pan, heated to 200 ° C. at 100 ° C./min, held at 200 ° C. for 5 minutes, then cooled to −150 ° C. at 10 ° C./min, and then 200 ° C. at 10 ° C./min. It calculated | required from the heat_generation | fever / endothermic curve at the time of heating up to degreeC.

(4) Molecular weight distribution (Mw / Mn)
The temperature was measured by GPC (gel permeation chromatography) at a temperature of 140 ° C. using an orthodichlorobenzene solvent.
(5) Density Measured according to the method described in ASTM D1505.
(6) RINT2500 (manufactured by Rigaku Corporation) was used as the crystallinity measuring device, and the wide angle X-ray profile was measured by using CuKα as the X-ray source.

<Evaluation items of Examples and Comparative Examples>
(1) Strength at break (TS), elongation at break (EL)
Based on JIS K7113-1, the strength at break (TS) and the elongation at break (EL) were measured with a 2 mmt press sheet.
(2) Scratch resistance (scrape wear)
A scrape wear tester (manufactured by Yasuda Seiki Seisakusho), a 0.45 mmφ piano wire, and 700 g of wear indenter were used. At a temperature of 23 ° C., a 2 mmφ strand sample was worn under the conditions that the wear indenter with the piano wire attached to the tip thereof had a reciprocating frequency of 50 times, a reciprocating speed of 1 time / second, and a stroke of 10 mm. Scratch resistance was evaluated from the change in thickness before and after abrasion. If the thickness change before and after abrasion is 0.15 mm or less under the above conditions, the scratch resistance is particularly excellent.

[ Reference Example 1]
The composition having the composition shown in Table 1 was kneaded using Labo Plast Mill (manufactured by Toyo Seiki Co., Ltd.). This was formed into a sheet having a thickness of 2 mm by a press molding machine (heating: temperature 190 ° C., 7 minutes, cooling: temperature 15 ° C., 4 minutes, cooling rate: about 40 ° C./minute). Table 1 shows the evaluation results of the breaking strength (TS) and elongation at break (EL) carried out on this sheet.

  Table 1 also shows the results of a scratch resistance test conducted using a test piece obtained by molding a composition having the composition shown in Table 1 into a 2 mmφ strand at a temperature of 230 ° C.

[ Reference Examples 2 and 3, Comparative Examples 1 and 2]
Evaluation was carried out in the same manner as in Reference Example 1 except that the composition was changed to the composition shown in Table 1. The results are shown in Table 1.

[Examples 4 to 6, Comparative Examples 3 and 4]
Evaluation was performed in the same manner as in Reference Example 1 except that the composition was changed to the composition shown in Table 2. The results are shown in Table 2.

  The propylene-based resin composition of the present invention exhibits mechanical strength represented by strength at break and superior scratch resistance (wear thickness loss) as compared with the comparative example.

[Example 7]
Evaluation was performed in the same manner as in Reference Example 1 except that the raw material was changed to the raw material having the composition shown in Table 3.

As shown in Example 7, it was confirmed that by using the graft-modified polymer, the propylene-based resin composition of the present invention has further excellent scratch resistance.

The propylene-based resin composition of the present invention contains an inorganic filler in a high proportion and is excellent in the balance of mechanical strength, flexibility, and scratch resistance. Furthermore, the propylene-based resin composition of the present invention can be widely used for molded products having flame retardancy, such as electric wires and building materials.

Claims (7)

5-84.5% by mass of the propylene polymer (A) having a melting point of 120 to 170 ° C. measured by a differential scanning calorimeter (DSC), and a melting point of 120 ° C. measured by differential scanning calorimetry (DSC). One or more elastomers selected from the group consisting of 0.5 to 4.5% by mass of the propylene-based polymer (B), ethylene-based elastomer (C-1) and styrene-based elastomer (C-2). total 0-40% by weight of (C), and an inorganic filler (D) containing only (where 15 to 80 wt%, (a), (B ), the sum of (C), and (D) component the amount is 100 wt%.)
The propylene-based resin composition, wherein the propylene-based polymer (B) is a propylene / α-olefin random copolymer (B-1) having 4 to 20 carbon atoms that satisfies the following (a) and (b):
(A) The molecular weight distribution (Mw / Mn) measured by gel permeation chromatography (GPC) is 1 to 3,
(B) The melting point Tm (° C.) and the content M (mol%) of comonomer constituent units determined by ¹³ C-NMR spectrum measurement,
146 exp (−0.022 M) ≧ Tm ≧ 125 exp (−0.032 M) (1)
(Where Tm is less than 120 ° C.). The propylene-based resin composition according to claim 1 , wherein the inorganic filler (D) is at least one selected from metal hydroxides, metal carbonates, and metal oxides. One or more elastomers (C) selected from a propylene polymer (A), a propylene polymer (B), an ethylene elastomer (C-1) and a styrene elastomer (C-2), and an inorganic filler The graft modified polymer, wherein the graft amount of the vinyl compound having a polar group is 0.01 to 10% by mass when the mass of the graft modified polymer is 100% by mass with respect to 100 parts by mass in total of (D). The propylene-type resin composition of Claim 1 or Claim 2 containing 0.1-30 mass parts of (E). The molded object which consists of a propylene-type resin composition in any one of Claims 1-3 . The molded body according to claim 4 , wherein the molded body is an electric wire insulator or an electric wire sheath. The insulator which uses the propylene-type resin composition in any one of Claims 1-3 , and / or the propylene-type resin composition in any one of Claims 1-3. An electric wire having a sheath. The electric wire according to claim 6 , wherein the electric wire is an automobile electric wire or an equipment electric wire.