Polypropylene-based resin composition and its use

Abstract

This polypropylene-based resin composition contains: 5-47 parts by mass of a propylene-based polymer (A) which has an MFR of 50-150 g / 10 min and a decane soluble part amount of 6-15 mass%; 20-30 parts by mass of a propylene homopolymer (B) which has an MFR of 10-500 g / 10 min; 23-30 parts by mass of an ethylene / α-olefin copolymer (C) that is a random copolymer of ethylene and a C4-8 α-olefin, has a density of 0.850-0.880 g / cm3, has an MFR of 0.5-30 g / 10 min, and has a melting point peak of 110°C or higher; and 30-40 parts by mass of an inorganic filler (D) (the total amount of components (A)-(D) being 100 parts by mass).

Description

Technical Field

[0001] The present invention relates to a polypropylene-based resin composition capable of producing a molded article having a low coefficient of linear expansion, high dimensional stability, and suitable for manufacturing a structure laminated with other members, and uses thereof.

Background Art

[0002] Molded articles obtained by injection molding polypropylene resin compositions are being increasingly used in various fields such as automotive parts and home appliance parts due to their excellent mechanical properties, moldability, and relatively advantageous cost performance compared to other materials.

[0003] In the field of automotive parts, in addition to using polypropylene alone, materials in which rubber components such as ethylene-propylene copolymer (EPR), ethylene-butene copolymer (EBR), ethylene-octene copolymer (EOR), styrene-butadiene copolymer (SBR), and polystyrene-ethylene / butene-polystyrene triblock copolymer (SEBS) are added to polypropylene to improve impact resistance, materials in which inorganic fillers such as talc, mica, and glass fiber are added to improve rigidity, and blend polymers in which both rubber components and inorganic fillers are added to impart well-balanced mechanical properties are used.

[0004] In recent years, mainly for the purpose of using as a substitute for metal materials, the need for developing materials that maintain high mechanical properties (mainly rigidity) and have excellent dimensional stability (low coefficient of linear expansion) has been increasing, and material development research has been conducted to achieve this. However, since polypropylene molded articles generally have a large dimensional change (coefficient of linear expansion) with respect to temperature, when applied to, for example, automotive outer panel applications in an environment with a large difference in temperature, there are problems such as gaps occurring at the joints of parts or deterioration of the buildability during part assembly, so-called gap quality defects. Therefore, in this field, the high designability and excellent cost effectiveness of polypropylene molded articles have not yet been fully enjoyed.

[0005] As a measure for improving the dimensional stability of polypropylene molded articles, various propylene resin compositions in which an inorganic filler typified by talc, an elastomer component, etc. are blended with polypropylene have been proposed. For example, a method for producing a low linear expansion material characterized by the combined use of a propylene block copolymer containing a crystalline polypropylene having a melt flow rate of 500 g / 10 minutes or more and a low molecular weight polyolefin (Patent Document 1), a resin composition in which a specific ethylene / butene-1 copolymer is blended with a propylene block copolymer (Patent Document 2), a resin composition characterized by defining the blending ratio and viscosity of the amorphous part and the crystalline part of a propylene block copolymer (Patent Document 3), a resin composition using talc having an average particle diameter of 3 μm or less and being excellent in the coating appearance after injection molding (Patent Document 4), a resin composition comprising a propylene-based resin produced with a Ziegler catalyst and talc having a specific shape (Patent Document 5), a resin composition characterized by using two types of propylene block copolymers having different melt flow rates and talc having a specific shape (Patent Document 6), etc. Further, as those for improving the surface impact resistance at a lower temperature, resin compositions containing a propylene-based block copolymer, a propylene homopolymer, an ethylene / α-olefin copolymer, and an inorganic filler in a specific quantitative ratio have been proposed (Patent Documents 7, 8).

[0006] In the field of automotive parts, in line with the need to reduce the weight of automobiles, resinification of outer panel materials is being actively promoted by each manufacturer. In this movement, the switch from metal to resin for the outer part of the back door has also been progressing. For this resinification of the outer panel material, dimensional accuracy comparable to that of metal is required from the viewpoint of design, and a material having a low linear expansion coefficient is necessary. Further, for the back door material, it is necessary to bond it to other members, and high adhesive performance is also required.

[0007] However, the above-mentioned documents do not teach means for improving the adhesive performance when the molded articles of these polypropylene-based resin compositions are bonded to other members, and with conventional polypropylene-based resin compositions, a molded article having both dimensional stability and high adhesive performance could not be obtained.

Prior Art Documents

Patent Documents

[0008]

Patent Document 1

Patent Document 2

Patent Document 3

Patent Document 4

Patent Document 5

Patent Document 6

Patent Document 7

Patent Document 8

Summary of the Invention

Problems to be Solved by the Invention

[0009] In order to reduce the linear expansion of a polypropylene-based molded article, it is necessary to increase the blending amount of the auxiliary material with a low coefficient of linear expansion as described above. Furthermore, in order to impart coating performance, it is also necessary to increase the compounding ratio of rubber. For these reasons, the polypropylene compound material for resin outer panels has a very high blending ratio of filler and rubber. However, when bonding with other members, interfacial peeling easily occurs at the interface between the auxiliary material and the polypropylene compound material during the adhesion test, and there has been a problem that the strength easily decreases. In addition, since polypropylene itself has no polar functional groups, it is necessary to perform frame treatment or plasma treatment in order to form a strong chemical bond with the adhesive. By performing this treatment, the surface of the base material is damaged and the adhesion strength easily decreases, which is also a problem. In order to ensure this adhesion strength, it is common to use a primer, but the use of a primer becomes a factor in high cost and an increase in the manufacturing process. Therefore, there is a demand for the emergence of a polypropylene-based molded article and a polypropylene-based resin composition capable of manufacturing a composite material that can achieve both high dimensional stability and high adhesion performance, and maintain the low coefficient of linear expansion required for outer panel materials, and has sufficient adhesion strength without a primer.

[0010] An object of the present invention is to provide a polypropylene-based resin composition and its use that can produce a molded article having a low coefficient of linear expansion, excellent dimensional stability, and high adhesion strength without a primer.

Means for Solving the Problems

[0011] As a result of intensive studies in view of the above situation, the present inventor has found that a polypropylene-based resin composition containing an ethylene-α-olefin copolymer having a very high melting point as an elastomer component can produce a molded article having excellent dimensional stability and excellent adhesiveness, and has completed the present invention.

[0012] The present invention relates to the following matters [1] to [8]. [(1) 5 to 47 parts by mass of a propylene-based polymer (A) having a melt flow rate (at 230°C and a load of 2.16 kg) of 50 to 150 g / 10 minutes and a decane-soluble portion content of 6 to 15% by mass, 20 to 30 parts by mass of a propylene homopolymer (B) having a melt flow rate (at 230°C and a load of 2.16 kg) of 10 to 500 g / 10 minutes, a random copolymer of ethylene and an α-olefin having 4 to 8 carbon atoms, with a density of 0.850 to 0.880 g / cm 3 , 23 to 30 parts by mass of an ethylene·α-olefin copolymer (C) having a melt flow rate (at 230°C and a load of 2.16 kg) of 0.5 to 30 g / 10 minutes and a melting point peak of 110°C or higher, and 30 to 40 parts by mass of an inorganic filler (D) [However, the total amount of components (A) to (D) is 100 parts by mass.] A polypropylene-based resin composition containing the same. [(2) The polypropylene-based resin composition according to (1), wherein the propylene-based polymer (A) is a block copolymer of propylene and ethylene, and the intrinsic viscosity [η] of the decane-soluble portion of the copolymer is 2 to 9 dl / g.] [(3) The polypropylene-based resin composition according to (1) or (2), wherein the inorganic filler (D) is talc and its aspect ratio is 3 or more and less than 15.] [(4) The polypropylene-based resin composition according to any one of (1) to (3), wherein in a primerless adhesion test, the hot shear test strength at 90°C exceeds 1.5 MPa.] [(5) The polypropylene-based resin composition according to any one of (1) to (4), which is used for an automotive exterior member.] [(6) A molded article made of the polypropylene-based resin composition according to any one of (1) to (5).] [(7) The molded article according to (6), which is an injection molded article or a press molded article.] [(8) The molded article according to (6) or (7), which is an automotive exterior member.] [Effect of the Invention]

[0013] According to the present invention, it is possible to provide a polypropylene-based resin composition capable of producing a molded article having a low linear expansion coefficient, excellent dimensional stability, and high adhesive strength to a urethane-based adhesive layer or the like without a primer, and uses thereof.

Brief Description of the Drawings

[0014]

Fig. 1

Embodiments for Carrying Out the Invention

[0015] Hereinafter, the present invention will be specifically described. Polypropylene-based resin composition The polypropylene-based resin composition of the present invention contains a propylene-based polymer (A), a propylene homopolymer (B), an ethylene·α-olefin copolymer (C), and an inorganic filler (D), and further contains other components as necessary.

[0016] <Propylene-based polymer (A)> The propylene-based polymer (A) used in the present invention is a propylene-based polymer having a melt flow rate (at 230°C, under a load of 2.16 kg) of 50 to 150 g / 10 minutes and a decane-soluble portion content of 6 to 15% by mass.

[0017] The propylene-based polymer (A) substantially contains 6 to 15% by mass of a decane-soluble portion (a1) and 85 to 94% by mass of a decane-insoluble portion (a2). The decane-insoluble portion (a2) is generally a component insoluble in an n-decane solvent at room temperature (23°C), and is usually equivalent to the propylene homopolymer portion (propylene homopolymer component) in the propylene-based polymer (A). The decane-soluble portion (a1) is equivalent to the portion other than the propylene homopolymer portion, and is preferably a copolymer portion of propylene and ethylene (ethylene·propylene copolymer component).

[0018] The propylene-based polymer (A) usually contains 6 to 15% by mass of a decane-soluble part (a1) and 85 to 94% by mass of a decane-insoluble part (a2), preferably 7 to 12% by mass of a decane-soluble part (a1) and 88 to 93% by mass of a decane-insoluble part (a2) [where the total content of (a1) and the content of (a2) is 100% by mass].

[0019] The propylene-based polymer (A) is preferably a propylene-based block copolymer obtained from propylene and ethylene. The intrinsic viscosity [η] of the decane-soluble part (a1) of this propylene-based block copolymer is preferably 2 to 9 dl / g, more preferably 3 to 8 dl / g.

[0020] The melt flow rate (at 230 °C, 2.16 kg load) of the propylene-based polymer (A) is 50 to 150 g / 10 min, preferably 50 to 130 g / 10 min, more preferably 60 to 120 g / 10 min, and particularly preferably 70 to 110 g / 10 min.

[0021] The propylene-based polymer (A) can be produced by a known method. For example, propylene is polymerized using a catalyst for olefin polymerization containing a solid titanium catalyst component (I) and an organometallic compound catalyst component (II) described below, and then propylene and ethylene are copolymerized to obtain a propylene-based block copolymer. [Solid titanium catalyst component (I)] The solid titanium catalyst component (I) constituting the catalyst for olefin polymerization contains, for example, titanium, magnesium, halogen, and an electron donor as required. Known components can be used for this solid titanium catalyst component (I) without limitation.

[0022] In the preparation of the solid titanium catalyst component (I), magnesium compounds and titanium compounds are often used.

[0023] Specific examples of the magnesium compound include magnesium halides such as magnesium chloride and magnesium bromide; alkoxymagnesium halides such as methoxymagnesium chloride, ethoxymagnesium chloride, and phenoxymagnesium chloride; alkoxymagnesiums such as ethoxymagnesium, isopropoxymagnesium, butoxymagnesium, and 2-ethylhexoxymagnesium; aryloxymagnesiums such as phenoxymagnesium; carboxylates of magnesium such as magnesium stearate; and the like. The magnesium compound may be used alone or in combination of two or more. The magnesium compound may also be a complex compound, a double compound with another metal, or a mixture with another metal compound.

[0024] Among them, a magnesium compound containing a halogen is preferred, and magnesium halide, particularly magnesium chloride, is more preferred. In addition, alkoxymagnesiums such as ethoxymagnesium are also preferred. The magnesium compound may also be a compound obtained by contacting an organic magnesium compound such as a Grignard reagent with titanium halide, silicon halide, alcohol halide, etc., which is derived from other substances.

[0025] Examples of the titanium compound include tetravalent titanium compounds represented by the following formula.

[0026] Ti(OR) g X 4-g (In the formula, R is a hydrocarbon group, X is a halogen atom, and g satisfies 0 ≦ g ≦ 4.) Specific examples of the titanium compound include titanium tetrahalides such as TiCl4 and TiBr4; trihalogenated alkoxytitaniums such as Ti(OCH3)Cl3, Ti(OC2H5)Cl3, Ti(O-n-C4H9)Cl3, Ti(OC2H5)Br3, and Ti(O-i-C4H9)Br3; dihalogenated alkoxytitaniums such as Ti(OCH3)2Cl2 and Ti(OC2H5)2Cl2; monohalogenated alkoxytitaniums such as Ti(OCH3)3Cl, Ti(O-n-C4H9)3Cl, and Ti(OC2H5)3Br; tetraalkoxytitaniums such as Ti(OCH3)4, Ti(OC2H5)4, Ti(OC4H9)4, and Ti(O-2-ethylhexyl)4; and the like. The titanium compound may be used alone or in combination of two or more. Among them, titanium tetrahalide is preferable, and titanium tetrachloride is more preferable.

[0027] As the magnesium compound and the titanium compound, for example, the compounds described in detail in JP-A-57-63310, JP-A-5-170843, etc. can also be used.

[0028] Specific examples of the preferable preparation method of the solid titanium catalyst component (I) used in the present invention include the following methods (P-1) to (P-4). (P-1) A method of bringing a solid adduct composed of a magnesium compound and an electron donor component (1) such as alcohol, an electron donor component (2) described later, and a titanium compound in a liquid state into contact with each other in a suspended state in the presence of an inert hydrocarbon solvent. (P-2) A method of bringing a solid adduct composed of a magnesium compound and an electron donor component (1), an electron donor component (2), and a titanium compound in a liquid state into contact with each other in a plurality of times. (P-3) A method of bringing a solid adduct composed of a magnesium compound and an electron donor component (1), an electron donor component (2), and a titanium compound in a liquid state into contact with each other in a suspended state in the presence of an inert hydrocarbon solvent and in a plurality of times. A method of contacting a magnesium compound in a liquid state composed of a magnesium compound and an electron donor component (1) with a titanium compound in a liquid state and an electron donor component (2).

[0029] When preparing the solid titanium catalyst component (I), the reaction temperature is preferably -30 to 150 °C, more preferably -25 to 130 °C, and particularly preferably -25 to 120 °C.

[0030] The preparation of the solid titanium catalyst component (I) can also be carried out in the presence of a known medium as required. Specific examples of the medium include aromatic hydrocarbons such as toluene having a slightly polar nature, and known aliphatic hydrocarbons or alicyclic hydrocarbons such as heptane, octane, decane, and cyclohexane. Among them, aliphatic hydrocarbons are preferred.

[0031] As the electron donor component (1) used for forming the solid adduct or the magnesium compound in a liquid state, known compounds that can solubilize the magnesium compound in the temperature range of room temperature to about 300 °C are preferred. For example, alcohols, aldehydes, amines, carboxylic acids, and mixtures thereof are preferred. Examples of these compounds include the compounds described in JP-A-57-63310 and JP-A-5-170843.

[0032] Specific examples of the alcohol that can solubilize the magnesium compound include aliphatic alcohols such as methanol, ethanol, propanol, butanol, isobutanol, ethylene glycol, 2-methylpentanol, 2-ethylbutanol, n-heptanol, n-octanol, 2-ethylhexanol, decanol, and dodecanol; alicyclic alcohols such as cyclohexanol and methylcyclohexanol; aromatic alcohols such as benzyl alcohol and methylbenzyl alcohol; aliphatic alcohols having an alkoxy group such as n-butyl cellosolve; and the like.

[0033] Specific examples of the carboxylic acid include organic carboxylic acids having 7 or more carbon atoms such as caprylic acid and 2-ethylhexanoic acid. Specific examples of the aldehyde include aldehydes having 7 or more carbon atoms such as capric aldehyde and 2-ethylhexyl aldehyde. Specific examples of the amine include amines having 6 or more carbon atoms such as heptylamine, octylamine, nonylamine, laurylamine, and 2-ethylhexylamine.

[0034] As the electron donor component (1), the above alcohols are preferred, and ethanol, propanol, butanol, isobutanol, hexanol, 2-ethylhexanol, and decanol are particularly preferred.

[0035] The composition ratio of magnesium in the obtained solid adduct or magnesium compound in the liquid state to the electron donor component (1) varies depending on the type of the compound used and thus cannot be generally defined. However, with respect to 1 mol of magnesium in the magnesium compound, the electron donor component (1) is preferably 2 mol or more, more preferably 2.3 mol or more, particularly preferably 2.7 mol or more, and 5 mol or less.

[0036] Particularly preferred examples of the electron donor optionally used in the solid titanium catalyst component (I) include aromatic carboxylic acid esters and / or compounds having two or more ether bonds via a plurality of carbon atoms (hereinafter referred to as "electron donor component (2)").

[0037] As this electron donor component (2), known aromatic carboxylic acid esters and polyether compounds that have been preferably used in conventional olefin polymerization catalysts, for example, the compounds described in JP-A-5-170843 and JP-A-2001-354714 can be used without limitation.

[0038] Examples of the aromatic carboxylic acid ester include, specifically, aromatic carboxylic acid monoesters such as benzoic acid ester and toluic acid ester, and aromatic polyvalent carboxylic acid esters such as phthalic acid esters. Among them, aromatic polyvalent carboxylic acid esters are preferred, and phthalic acid esters are more preferred. Examples of the phthalic acid esters include alkyl phthalic acid esters such as ethyl phthalate, n-butyl phthalate, isobutyl phthalate, hexyl phthalate, and heptyl phthalate, and diisobutyl phthalate is particularly preferred.

[0039] Examples of the polyether compound include, specifically, a compound represented by the following chemical structural formula (1).

[0040] [Chemical formula] In the above formula (1), m is an integer of 1 ≤ m ≤ 10, more preferably an integer of 3 ≤ m ≤ 10, and R 11 ~R 36 are each independently a hydrogen atom or a substituent having at least one element selected from carbon, hydrogen, oxygen, fluorine, chlorine, bromine, iodine, nitrogen, sulfur, phosphorus, boron, and silicon. When m is 2 or more, a plurality of R 11 and R 12 may be the same or different from each other. Any R 11 ~R 36 , preferably R 11 and R 12 may jointly form a ring other than the benzene ring.

[0041] Specific examples of such compounds include monosubstituted dialkoxypropanes such as 2-isopropyl-1,3-dimethoxypropane, 2-s-butyl-1,3-dimethoxypropane, 2-cumyl-1,3-dimethoxypropane; disubstituted dialkoxypropanes such as 2-isopropyl-2-isobutyl-1,3-dimethoxypropane, 2,2-dicyclohexyl-1,3-dimethoxypropane, 2-methyl-2-isopropyl-1,3-dimethoxypropane, 2-methyl-2-cyclohexyl-1,3-dimethoxypropane, 2-methyl-2-isobutyl-1,3-dimethoxypropane, 2,2-diisobutyl-1,3-dimethoxypropane, 2,2-bis(cyclohexylmethyl)-1,3-dimethoxypropane, 2,2-diisobutyl-1,3-diethoxypropane, 2,2-diisobutyl-1,3-dibutoxypropane, 2,2-di-s-butyl-1,3-dimethoxypropane, 2,2-dineopentyl-1,3-dimethoxypropane, 2-isopropyl-2-isopentyl-1,3-dimethoxypropane, 2-cyclohexyl-2-cyclohexylmethyl-1,3-dimethoxypropane; dialkoxyalkanes such as 2,3-dicyclohexyl-1,4-diethoxybutane, 2,3-dicyclohexyl-1,4-diethoxybutane, 2,3-diisopropyl-1,4-diethoxybutane, 2,4-diphenyl-1,5-dimethoxypentane, 2,5-diphenyl-1,5-dimethoxyhexane, 2,4-diisopropyl-1,5-dimethoxypentane, 2,4-diisobutyl-1,5-dimethoxypentane, 2,4-diisoamyl-1,5-dimethoxypentane; trialkoxyalkanes such as 2-methyl-2-methoxymethyl-1,3-dimethoxypropane, 2-cyclohexyl-2-ethoxymethyl-1,3-diethoxypropane, 2-cyclohexyl-2-methoxymethyl-1,3-dimethoxypropane; etc. The polyether compound may be used alone or in combination of two or more kinds.Among them, 1,3 - diethers are preferred, and in particular, 2 - isopropyl - 2 - isobutyl - 1,3 - dimethoxypropane, 2,2 - diisobutyl - 1,3 - dimethoxypropane, 2 - isopropyl - 2 - isopentyl - 1,3 - dimethoxypropane, 2,2 - dicyclohexyl - 1,3 - dimethoxypropane, 2,2 - bis(cyclohexylmethyl)1,3 - dimethoxypropane are preferred.

[0042] In the solid titanium catalyst component (I), the halogen / titanium (atomic ratio) (i.e., the number of moles of halogen atoms / the number of moles of titanium atoms) is 2 to 100, preferably 4 to 90, the electron donor component (1) / titanium atom (molar ratio) is 0 to 100, preferably 0 to 10, and the electron donor component (2) / titanium atom (molar ratio) is 0 to 100, preferably 0 to 10. The magnesium / titanium (atomic ratio) (i.e., the number of moles of magnesium atoms / the number of moles of titanium atoms) is 2 to 100, preferably 4 to 50.

[0043] As more detailed preparation conditions of the solid titanium catalyst component (I), except for using the electron donor component (2), for example, the conditions described in EP585869A1, JP - A - 5 - 170843, etc. can be preferably used.

[0044] [Organometallic compound catalyst component (II)] The organometallic compound catalyst component (II) is a component containing a metal element selected from Group 1, Group 2, and Group 13 of the periodic table. For example, compounds containing Group 13 metals (such as organoaluminum compounds), complex alkylates of Group 1 metals and aluminum, organometallic compounds of Group 2 metals, etc. can be used. Among them, organoaluminum compounds are preferred.

[0045] Specifically, as the organometallic compound catalyst component (II), the organometallic compound catalyst components described in known literatures such as the above - mentioned EP585869A1 can be preferably used.

[0046] As long as the object of the present invention is not impaired, in addition to the electron donor component (1) and the electron donor component (2) described above, a known electron donor component (3) may be used in combination.

[0047] As the electron donor component (3), an organosilicon compound is preferable. This organosilicon compound is, for example, a compound represented by the following formula.

[0048] R n Si(OR') 4-n (In the formula, R and R' are hydrocarbon groups, and n is an integer of 0 < n < 4.) Specific examples of the organosilicon compound represented by the above formula include diisopropyldimethoxysilane, t-butylmethyldimethoxysilane, t-butylmethyldiethoxysilane, t-amylmethyldiethoxysilane, dicyclohexyldimethoxysilane, cyclohexylmethyldimethoxysilane, cyclohexylmethyldiethoxysilane, vinyltrimethoxysilane, vinyltriethoxysilane, t-butyltriethoxysilane, phenyltriethoxysilane, diphenyldimethoxysilane, cyclohexyltrimethoxysilane, cyclopentyltrimethoxysilane, 2-methylcyclopentyltrimethoxysilane, cyclopentyltriethoxysilane, dicyclopentyldimethoxysilane, dicyclopentyldiethoxysilane, tricyclopentylmethoxysilane, dicyclopentylmethylmethoxysilane, dicyclopentylethylmethoxysilane, cyclopentyldimethylethoxysilane, etc. Among them, vinyltriethoxysilane, diphenyldimethoxysilane, dicyclohexyldimethoxysilane, cyclohexylmethyldimethoxysilane, dicyclopentyldimethoxysilane are preferable.

[0049] In addition, a silane compound represented by the following formula described in International Publication No. 2004 / 016662 pamphlet is also a preferable example of the organosilicon compound.

[0050] Si(OR a )3(NR b R c ) In the above formula, R a is a hydrocarbon group having 1 to 6 carbon atoms. For example, it is an unsaturated or saturated aliphatic hydrocarbon group having 1 to 6 carbon atoms, and particularly preferably a hydrocarbon group having 2 to 6 carbon atoms. Specific examples include a methyl group, an ethyl group, an n-propyl group, an iso-propyl group, an n-butyl group, an iso-butyl group, a sec-butyl group, an n-pentyl group, an iso-pentyl group, a cyclopentyl group, an n-hexyl group, a cyclohexyl group, etc. Among them, an ethyl group is particularly preferred.

[0051] R b is a hydrocarbon group having 1 to 12 carbon atoms or hydrogen. For example, it is an unsaturated or saturated aliphatic hydrocarbon group having 1 to 12 carbon atoms or hydrogen. Specific examples include a hydrogen atom, a methyl group, an ethyl group, an n-propyl group, an iso-propyl group, an n-butyl group, an iso-butyl group, a sec-butyl group, an n-pentyl group, an iso-pentyl group, a cyclopentyl group, an n-hexyl group, a cyclohexyl group, an octyl group, etc. Among them, an ethyl group is particularly preferred.

[0052] R c is a hydrocarbon group having 1 to 12 carbon atoms. For example, it is an unsaturated or saturated aliphatic hydrocarbon group having 1 to 12 carbon atoms. Specific examples include a methyl group, an ethyl group, an n-propyl group, an iso-propyl group, an n-butyl group, an iso-butyl group, a sec-butyl group, an n-pentyl group, an iso-pentyl group, a cyclopentyl group, an n-hexyl group, a cyclohexyl group, an octyl group, etc. Among them, an ethyl group is particularly preferred.

[0053] Specific examples of the organosilicon compound represented by the above formula include dimethylaminotriethoxysilane, diethylaminotriethoxysilane, diethylaminotrimethoxysilane, diethylaminotri-n-propoxysilane, di-n-propylaminotriethoxysilane, methyl n-propylaminotriethoxysilane, t-butylaminotriethoxysilane, ethyl n-propylaminotriethoxysilane, ethyl iso-propylaminotriethoxysilane, methylethylaminotriethoxysilane, etc.

[0054] Furthermore, as other examples of the organosilicon compound, compounds represented by the following formula can also be mentioned.

[0055] RNSi(OR a )3 In the above formula, RN is a cyclic amino group. Specific examples include a perhydroquinolino group, a perhydroisoquinolino group, a 1,2,3,4-tetrahydroquinolino group, a 1,2,3,4-tetrahydroisoquinolino group, an octamethyleneimino group, etc. R a is the same as described above.

[0056] Specific examples of the organosilicon compound represented by the above formula include (perhydroquinolino)triethoxysilane, (perhydroisoquinolino)triethoxysilane, (1,2,3,4-tetrahydroquinolino)triethoxysilane, (1,2,3,4-tetrahydroisoquinolino)triethoxysilane, octamethyleneiminotriethoxysilane, etc. Two or more of the above-described organosilicon compounds may be used in combination.

[0057] [Polymerization] A propylene-ethylene block copolymer, which is a preferred embodiment of the propylene-based polymer (A), can be produced by polymerizing propylene in the presence of the above-described olefin polymerization catalyst and then copolymerizing propylene and ethylene, or by polymerizing propylene in the presence of a prepolymerization catalyst obtained by prepolymerizing and then performing copolymerization of propylene and ethylene.

[0058] The prepolymerization is carried out by prepolymerizing an olefin in an amount of usually 0.1 to 1000 g, preferably 0.3 to 500 g, particularly preferably 1 to 200 g per 1 g of the olefin polymerization catalyst. In the prepolymerization, a catalyst having a higher concentration than the catalyst concentration in the main polymerization can be used.

[0059] In prepolymerization, the concentration of the solid titanium catalyst component (I) is usually 0.001 to 200 mmol, preferably 0.01 to 50 mmol, more preferably 0.1 to 20 mmol in terms of titanium atoms per liter of the liquid medium.

[0060] In prepolymerization, the amount of the organometallic compound catalyst component (II) is such that usually 0.1 to 1000 g, preferably 0.3 to 500 g of a polymer is produced per 1 g of the solid titanium catalyst component (I), and is usually 0.1 to 300 mol, preferably 0.5 to 100 mol, more preferably 1 to 50 mol per mole of titanium atoms in the solid titanium catalyst component (I).

[0061] In prepolymerization, the electron donor component can be used as necessary. In this case, these components are usually 0.1 to 50 mol, preferably 0.5 to 30 mol, more preferably 1 to 10 mol per mole of titanium atoms in the solid titanium catalyst component (I).

[0062] Prepolymerization can be carried out by adding an olefin and the above catalyst components to an inert hydrocarbon medium under mild conditions. When using an inert hydrocarbon medium, prepolymerization is preferably carried out in a batch mode.

[0063] Specific examples of the inert hydrocarbon medium include aliphatic hydrocarbons such as propane, butane, pentane, hexane, heptane, octane, decane, dodecane, and kerosene; alicyclic hydrocarbons such as cyclopentane, methylcyclopentane, cyclohexane, cycloheptane, methylcycloheptane, and cyclooctane; aromatic hydrocarbons such as benzene, toluene, and xylene; halogenated hydrocarbons such as ethylene chloride and chlorobenzene; or mixtures thereof. Among them, aliphatic hydrocarbons are preferred.

[0064] Prepolymerization can also be carried out using the olefin itself as a solvent. Also, prepolymerization can be carried out in a substantially solvent-free state. In this case, it is preferable to carry out prepolymerization continuously.

[0065] The olefin used in the prepolymerization may be the same as or different from the olefin used in the main polymerization described below. As the olefin, propylene is particularly preferred.

[0066] The temperature during the prepolymerization is usually -20 to 100 °C, preferably -20 to 80 °C, more preferably 0 to 40 °C.

[0067] Next, the main polymerization, which is carried out after passing through the prepolymerization or without passing through the prepolymerization, will be described.

[0068] The main polymerization is divided into a step of producing a propylene homopolymer component and a step of producing a propylene-ethylene copolymer component.

[0069] The main polymerization (and the prepolymerization) can be carried out by any of the liquid phase polymerization methods such as the bulk polymerization method, solution polymerization, suspension polymerization, or the gas phase polymerization method. As the step of producing the propylene homopolymer component, a liquid phase polymerization method such as bulk polymerization or suspension polymerization or the gas phase polymerization method is preferred. As the step of producing the propylene-ethylene copolymer component, a liquid phase polymerization method such as bulk polymerization or suspension polymerization or the gas phase polymerization method is preferred, and the gas phase polymerization method is more preferred.

[0070] When the main polymerization adopts the reaction form of slurry polymerization, as the reaction solvent, the inert hydrocarbon used during the above-mentioned prepolymerization can be used, or an olefin that is liquid at the reaction temperature and pressure can also be used.

[0071] In this polymerization, the solid titanium catalyst component (I) is usually used in an amount of 0.0001 to 0.5 mmol, preferably 0.005 to 0.1 mmol, in terms of titanium atoms per liter of the polymerization volume. Further, the organometallic compound catalyst component (II) is usually used in an amount of 1 to 2000 moles, preferably 5 to 500 moles, per mole of titanium atoms in the prepolymerization catalyst component in the polymerization system. When an electron donor component is used, it is usually used in an amount of 0.001 to 50 moles, preferably 0.01 to 30 moles, more preferably 0.05 to 20 moles, per mole of the organometallic compound catalyst component (II).

[0072] If this polymerization is carried out in the presence of hydrogen, the molecular weight of the resulting polymer can be adjusted (lowered), and a polymer with a large melt flow rate (MFR) can be obtained. Since the amount of hydrogen required to adjust the molecular weight varies depending on the type of production process used, the polymerization temperature, and the pressure, it may be adjusted as appropriate.

[0073] In the step of producing a propylene homopolymer component, the MFR can be adjusted by adjusting the polymerization temperature and the amount of hydrogen. Also, in the step of producing a propylene-ethylene copolymer component, the intrinsic viscosity can be adjusted by adjusting the polymerization temperature, the pressure, and the amount of hydrogen.

[0074] In this polymerization, the polymerization temperature of the olefin is usually 0 to 200°C, preferably 30 to 100°C, more preferably 50 to 90°C. The pressure (gauge pressure) is usually atmospheric pressure to 100 kgf / cm 2 (9.8 MPa), preferably 2 to 50 kgf / cm 2 (0.20 to 4.9 MPa).

[0075] In the production of a propylene-ethylene block copolymer, which is a preferred embodiment of the propylene-based polymer (A), the polymerization can be carried out in any of the batch, semi-continuous, and continuous methods. Further, any of the tubular type and the tank type can be used as the shape of the reactor. Furthermore, the polymerization can also be carried out in two or more stages by changing the reaction conditions. In this case, the tubular type and the tank type can be combined.

[0076] In order to obtain the propylene-ethylene copolymer portion in the propylene-ethylene block copolymer, which is a preferred embodiment of the propylene-based polymer (A), the ethylene / (ethylene + propylene) gas ratio is controlled in Polymerization Step 2 described below. The ethylene / (ethylene + propylene) gas ratio is usually 5 to 80 mol%, preferably 10 to 70 mol%, more preferably 15 to 60 mol%.

[0077] As described above, the decane-insoluble portion (a2) of the propylene-ethylene block copolymer is mainly composed of a propylene homopolymer component. On the other hand, the decane-soluble portion (a1) is mainly composed of an ethylene-propylene copolymer component which is a rubbery component. For example, by continuously carrying out the following two polymerization steps 1 and 2, a propylene-ethylene block copolymer, which is a preferred embodiment of the propylene-based polymer (A), can be obtained. (Polymerization Step 1) A step of polymerizing propylene in the presence of a solid titanium catalyst component to produce a propylene homopolymer component (propylene homopolymer production step). (Polymerization Step 2) A step of copolymerizing propylene and ethylene in the presence of a solid titanium catalyst component to produce an ethylene-propylene copolymer component (copolymer rubber production step).

[0078] In particular, it is more preferable to carry out Polymerization Step 1 in the first stage and Polymerization Step 2 in the second stage. Each of Polymerization Steps 1 and 2 can also be carried out using two or more polymerization tanks. The content of the decane-soluble portion (a1) can be adjusted by the polymerization time (residence time) of Polymerization Step 1 and Polymerization Step 2. Further, the previous Polymerization Step 1 may be carried out in two or more series-connected polymerizers. In that case, the ratio of propylene to hydrogen in each stage may be different for each polymerizer.

[0079] The propylene-based polymer (A) used in the present invention may contain one or more biomass-derived monomers. The same type of monomers constituting the polymer may be only biomass-derived monomers, or may contain both biomass-derived monomers and fossil fuel-derived monomers. Biomass-derived monomers are monomers made from any renewable natural raw materials and their residues, such as plant-derived or animal-derived, including fungi, yeast, algae, and bacteria, and as carbon 14 contains C isotope at a ratio of about 10 -12 and the biomass carbon concentration (pMC) measured in accordance with ASTM D 6866 is about 100 (pMC). Biomass-derived monomers can be obtained by conventionally known methods. It is preferable from the viewpoint of reducing environmental load that the propylene-based polymer (A) used in the present invention contains biomass-derived monomers. If the polymerization conditions such as the polymerization catalyst and the polymerization temperature are the same, even if the raw material olefin contains biomass-derived olefin, 14 except for containing C isotope at a ratio of about 10 -12 the molecular structure is equivalent to that of a propylene-based polymer composed of fossil fuel-derived monomers. Therefore, the performance is also considered to be unchanged.

[0080] In addition, the propylene-based polymer (A) according to the present invention may contain propylene derived from chemical recycling. The propylene constituting the polymer may be only propylene derived from chemical recycling, or may contain propylene derived from chemical recycling, propylene derived from fossil fuels, and / or propylene derived from biomass. Propylene derived from chemical recycling can be obtained by conventionally known methods. The fact that the propylene-based polymer (A) according to the present invention contains propylene derived from chemical recycling is preferable from the viewpoint of reducing the environmental load (mainly reducing waste). Even if the raw material monomer contains a monomer derived from chemical recycling, the monomer derived from chemical recycling is a monomer obtained by depolymerizing a polymer such as waste plastic into monomer units such as propylene by depolymerization, thermal decomposition, etc., and a monomer produced using the monomer as a raw material. Therefore, if the polymer production conditions such as the polymerization catalyst, polymerization process, and polymerization temperature are the same, the molecular structure is equivalent to that of a propylene homopolymer composed of monomers derived from fossil fuels. Therefore, the performance is also said to be unchanged.

[0081] <Propylene homopolymer (B)> The propylene homopolymer (B) used in the present invention is a propylene homopolymer having a melt flow rate (at 230 °C and a load of 2.16 kg) of 10 to 500 g / 10 min.

[0082] The propylene homopolymer (B) may be a polymer obtained by polymerizing substantially only propylene. For example, a homopolymer obtained by polymerizing only propylene, or a crystalline polymer obtained by copolymerizing propylene with 6 mol% or less, preferably 3 mol% or less of other α-olefins can be used. Among them, a homopolymer obtained by polymerizing only propylene is preferable.

[0083] The propylene homopolymer (B) can be produced by polymerizing a monomer mainly composed of propylene by a known method. For example, it can be obtained by polymerizing a monomer mainly composed of propylene in the presence of an olefin polymerization catalyst containing the solid titanium catalyst component (I) and the organometallic compound catalyst component (II) described above, or a combined catalyst of titanium trichloride and an alkylaluminum compound, which is usually called a Ziegler-Natta type catalyst. The polymerization reaction may be carried out continuously or batchwise. Also, for example, it can be preferably produced by performing only the polymerization step 1 described above.

[0084] In the polymerization reaction, the polymerization temperature is usually 0 to 200°C, preferably 30 to 100°C, more preferably 50 to 90°C. The pressure (gauge pressure) is usually atmospheric pressure to 100 kgf / cm 2 (9.8 MPa), preferably 2 to 50 kgf / cm 2 (0.20 to 4.9 MPa).

[0085] The melt flow rate (at 230°C, 2.16 kg load) of the propylene homopolymer (B) is 10 to 500 g / 10 min, preferably 10 to 300 g / 10 min, more preferably 20 to 250 g / 10 min.

[0086] The propylene homopolymer (B) used in the present invention may be a single polymer, or two or more propylene homopolymers may be arbitrarily combined within the range satisfying the above melt flow rate as a whole.

[0087] The propylene homopolymer (B) used in the present invention may contain biomass-derived propylene. The propylene constituting the polymer may be only biomass-derived propylene, or may contain both biomass-derived propylene and fossil fuel-derived propylene. Biomass-derived propylene is a monomer made from any renewable natural raw materials and their residues, including plant-derived or animal-derived ones such as fungi, yeast, algae, and bacteria, and as carbon 14 C isotope is 10 -12It is contained at a certain percentage, and the biomass carbon concentration (pMC) measured in accordance with ASTM D 6866 is about 100 (pMC). Propylene derived from biomass can be obtained by a conventionally known method. It is preferable from the viewpoint of reducing the environmental load that the propylene homopolymer (B) used in the present invention contains a biomass-derived monomer. If the polymerization conditions such as the polymerization catalyst and the polymerization temperature are the same, even if the raw material propylene contains biomass-derived propylene, 14 C isotope is 10 -12 The molecular structure other than containing at a certain percentage is equivalent to a propylene homopolymer composed of fossil fuel-derived propylene. Therefore, the performance is said to be unchanged.

[0088] Also, the propylene homopolymer (B) used in the present invention may contain propylene derived from chemical recycling as a monomer, similar to the above-described propylene-based polymer (A). That is, the propylene constituting the polymer may be only propylene derived from chemical recycling, or may contain propylene derived from chemical recycling and fossil fuel-derived propylene and / or biomass-derived propylene.

[0089] <Ethylene·α-olefin copolymer (C)> The ethylene·α-olefin copolymer (C) used in the present invention is a random copolymer of ethylene and an α-olefin having 4 to 8 carbon atoms, and has a density of 0.850 to 0.880 g / cm 3 It is an ethylene·α-olefin copolymer having a melt flow rate (230°C, 2.16 kg load) of 0.5 to 30 g / 10 minutes and a melting point peak of 110°C or higher. This ethylene·α-olefin copolymer (C) is expected to contribute to the improvement of the dimensional stability (reduction of the linear expansion coefficient) of the molded body obtained from the resin composition by the synergistic effect with other components, and also contributes to the improvement of other physical properties, and a high physical property balance is exhibited in the molded product.

[0090] As the α-olefin having 4 to 8 carbon atoms constituting the ethylene·α-olefin copolymer (C), 1-butene, 1-hexene, and 1-octene are preferable. The α-olefin may be used alone or in combination of two or more. As the ethylene·α-olefin copolymer (C), an ethylene-octene copolymer and an ethylene-butene copolymer are particularly preferable.

[0091] The melt flow rate (at 230°C, 2.16 kg load) of the ethylene·α-olefin copolymer (C) is 0.5 to 30 g / 10 min, preferably 1 to 25 g / 10 min, more preferably 2 to 20 g / 10 min.

[0092] If the melt flow rate (at 230°C, 2.16 kg load) of the ethylene·α-olefin copolymer (C) is 0.5 g / 10 min or more, it is difficult for the fluidity of the polypropylene-based resin composition to decrease or for poor dispersion during kneading to occur, and it is difficult for the physical properties such as impact resistance to decrease or for the surface appearance of the molded product to deteriorate. Also, if the melt flow rate (at 230°C, 2.16 kg load) is 30 g / 10 min or less, the molded body obtained from the resin composition tends to have sufficient impact resistance.

[0093] The density of the ethylene·α-olefin copolymer (C) is 0.850 to 0.880 g / cm 3 and preferably 0.855 to 0.875 g / cm 3 is.

[0094] The melting point peak of the ethylene·α-olefin copolymer (C) is 110°C or higher, preferably 110 to 130°C. The melting point peak means the value obtained by a differential scanning calorimeter (DSC). Specifically, when obtaining the endothermic curve of the differential scanning calorimeter (DSC), the temperature at the maximum peak position can be obtained as the melting point peak (Tm). By the melting point peak of the ethylene·α-olefin copolymer (C) satisfying the above high temperature range, a molded body made of a polypropylene-based resin composition containing this has excellent adhesive strength with a curable resin layer formed from a urethane-based adhesive, etc.

[0095] <Inorganic filler (D)> As the inorganic filler (D) used in the present invention, known inorganic fillers can be used, and it is not particularly limited. For example, talc, calcium carbonate, natural mica, synthetic mica, wollastonite, montmorillonite, etc. can be mentioned. The inorganic filler (D) may be used alone or in combination of two or more. Among them, talc is preferred. When the polypropylene-based resin composition of the present invention contains the inorganic filler (D), the mechanical properties of the molded body obtained from the resin composition are excellent.

[0096] The inorganic filler (D) only needs to be dispersed in the resin composition and is not particularly limited. However, its average particle size is, for example, 1 μm to 20 μm, preferably more than 3.0 μm and 10.0 μm or less, preferably 3.0 μm to 8.0 μm, more preferably 3.0 μm to 7.0 μm. This average particle size is a value measured by the laser diffraction method. Specifically, it is the particle size at the integrated value of 50% in the particle size distribution obtained by a particle size distribution meter such as a laser diffraction scattering type particle size distribution meter. Examples of the measuring device include MT3300EXII manufactured by Microtrac and LA-920 type manufactured by Horiba, Ltd.

[0097] The aspect ratio of the inorganic filler (D) is not particularly limited, but is usually 3 or more and less than 15, preferably 4 to 13, more preferably 5 to 11. Generally, the aspect ratio represents the ratio of the major axis to the thickness or the ratio of the long side to the short side of the filler. If this aspect ratio is 3 or more, the rigidity and dimensional stability of the molded body tend to be less likely to decrease. If it is less than 15, the balance of mechanical properties is less likely to decrease, and the impact resistance is also less likely to decrease. Specifically, this aspect ratio is a value obtained by taking a photograph using an electron microscope, measuring the major axis and thickness of the powder, obtaining the average value, and calculating the ratio of the average particle size / average thickness.

[0098] The inorganic filler (D) contributes to the improvement of the dimensional stability (reduction of the linear expansion coefficient) of the molded article obtained from the resin composition, and also contributes to the improvement of mechanical properties such as rigidity and impact resistance. When the inorganic filler (D) has the above-described average particle diameter (and aspect ratio), due to the synergistic effect with other components, it is particularly suitable because it is likely to exhibit excellent dimensional stability and an advanced physical property balance excellent in rigidity and impact resistance.

[0099] As the inorganic filler (D), inorganic fillers of any shape such as granular, plate-like, rod-like, fibrous, whisker-like, etc. can be used. Also, commercially available inorganic fillers as fillers for polymers can be used. Furthermore, in addition to general powder-like and roving-like forms, forms such as chopped strand-like, compressed pellet-like, pellet (granulated)-like, granular-like, etc. that enhance handling convenience can also be used. Among them, powder-like, compressed pellet-like, and granular-like are preferred.

[0100] The inorganic filler (D) may be a mixture of two or more inorganic fillers.

[0101] The production method of the inorganic filler (D) is not particularly limited and can be produced by various known methods. When, for example, talc is used as the inorganic filler (D), talc having a specific average particle diameter and aspect ratio can be produced by pulverization or granulation. Specifically, for example, there is a method of pulverizing the raw talc with an impact pulverizer or a micron mill-type pulverizer, then further pulverizing it with a jet mill, and classifying and adjusting it with a cyclone or a micron separator. The aspect ratio and average particle diameter of talc can be appropriately adjusted by the pulverizing apparatus and the pulverizing time, and talc with a controlled shape can be obtained by classifying as necessary.

[0102] As the inorganic filler (D), those obtained by pulverizing the raw stone may be directly used, or those obtained by subjecting at least a part thereof to surface treatment may also be used. For the surface treatment, for example, various surface treatment agents such as organic titanate coupling agents, organic silane coupling agents, unsaturated carboxylic acids, or modified polyolefins grafted with their anhydrides, fatty acids, fatty acid metal salts, and fatty acid esters can be used. The surface treatment agent may be used alone or in combination of two or more kinds.

[0103] In the polypropylene-based resin composition according to the present invention, if necessary, other additives such as nucleating agents, heat stabilizers, antistatic agents, weather stabilizers, light stabilizers, anti-aging agents, antioxidants, fatty acid metal salts, softeners, dispersants, fillers, colorants, lubricants, and pigments can be blended within a range not impairing the object of the present invention. The mixing order of the additives is arbitrary, and they may be mixed simultaneously, or a multi-stage mixing method such as mixing some components first and then mixing other components can also be used. <Polypropylene-based resin composition> The polypropylene-based resin composition according to the present invention contains 5 to 47 parts by mass of a propylene-based polymer (A), 20 to 30 parts by mass of a propylene homopolymer (B), 23 to 30 parts by mass of an ethylene·α-olefin copolymer (C), and 30 to 40 parts by mass of an inorganic filler (D) [wherein the total amount of components (A) to (D) is 100 parts by mass].

[0104] The polypropylene-based resin composition according to the present invention preferably contains 7 to 35 parts by mass of a propylene-based polymer (A), 20 to 30 parts by mass of a propylene homopolymer (B), 23 to 28 parts by mass of an ethylene·α-olefin copolymer (C), and 32 to 40 parts by mass of an inorganic filler (D) [wherein the total amount of components (A) to (D) is 100 parts by mass].

[0105] The polypropylene resin composition according to the present invention preferably contains 8 to 28 parts by mass of a propylene-based polymer (A), 23 to 30 parts by mass of a propylene homopolymer (B), 24 to 28 parts by mass of an ethylene-α-olefin copolymer (C), and 33 to 38 parts by mass of an inorganic filler (D) [wherein the total amount of components (A) to (D) is 100 parts by mass].

[0106] The polypropylene resin composition according to the present invention particularly preferably contains 10 to 22 parts by mass of a propylene-based polymer (A), 25 to 30 parts by mass of a propylene homopolymer (B), 24 to 27 parts by mass of an ethylene-α-olefin copolymer (C), and 34 to 37 parts by mass of an inorganic filler (D) [wherein the total amount of components (A) to (D) is 100 parts by mass].

[0107] The polypropylene resin composition according to the present invention can be produced by blending the above-described components (A) to (D) and optional components such as additives as required. The components may be sequentially blended in any order or simultaneously mixed. Also, a multi-step mixing method may be employed in which some components are mixed first and then other components are mixed. Specifically, for example, it can also be produced by first blending components (A) to (C) which are resin components (organic compound components) in the polypropylene resin composition, and then adding and blending component (D) and optional components such as additives as required.

[0108] Examples of the blending method of each component include a method of simultaneously or sequentially mixing or melt-kneading each component using a mixing device such as a Banbury mixer, a single-screw extruder, a twin-screw extruder, or a high-speed twin-screw extruder.

[0109] The melt flow rate (at 230 °C, 2.16 kg load) of the polypropylene resin composition of the present invention is usually 23 g / 10 min or more, preferably more than 23 g / 10 min and 50 g / 10 min or less. By setting the melt flow rate within such a range, the moldability becomes good and the deterioration of the coating appearance after injection molding can be suppressed. The polypropylene-based resin composition of the present invention can be suitably used in various fields such as automotive interior and exterior members (especially automotive exterior members), home appliance parts, and the like.

[0110] Molded article made of polypropylene-based resin composition The molded article made of the polypropylene-based resin composition of the present invention is a molded article obtained from the above-described polypropylene-based resin composition of the present invention. Such a molded article of the present invention can be obtained by appropriately molding the polypropylene-based resin composition of the present invention. The molding method of the polypropylene-based resin composition is not particularly limited, and various known methods as molding methods of resin compositions can be used. As the molding method of the molded article of the present invention, injection molding and press molding are particularly preferable.

[0111] The molded article of the present invention has a low coefficient of linear expansion, small dimensional changes due to temperature changes, excellent dimensional stability, and excellent adhesiveness to curable resins. The molded article of the present invention has excellent adhesiveness to a curable resin having a urethane bond, and particularly shows high adhesive strength even in the case without a primer (primerless) between the molded article and a curable resin layer formed from a urethane-based adhesive.

[0112] Specifically, when a surface treatment is performed on the surface of the molded article as necessary, and a curable resin layer obtained by curing a urethane-based adhesive containing a urethane prepolymer having a polyether backbone and an aliphatic isocyanate derivative is formed without using a primer, the 90°C hot shear test strength (tensile speed: 50 mm / min) measured in a primerless adhesion test according to JIS K6850:1999 is usually 1.2 MPa or more, preferably exceeding 1.5 MPa, more preferably exceeding 2.0 MPa, and even more preferably 2.5 MPa or more, showing excellent adhesive strength.

[0113] The molded article of the present invention can be suitably used as automotive interior materials such as door trims, instrument panels, ceilings, console boxes, pillars, glove boxes, etc.; automotive exterior members such as bumpers, side guards, air spoilers, side protectors, fenders, door panels, back doors, etc., industrial parts such as home appliance parts, building materials, etc. Further, since the molded article of the present invention is excellent in adhesiveness to a curable resin having a urethane bond, it can be suitably used as a raw material for composite members with other members, such as a laminate with a curable resin having a urethane bond and a laminate laminated with other members via a urethane-based adhesive. For example, it can be particularly suitably used for applications of automotive exterior members such as back doors.

Examples

[0114] Hereinafter, the present invention will be described more specifically based on examples, but the present invention is not limited to these examples.

[0115] The measurement and evaluation of each physical property were carried out by the following methods. [Melt Flow Rate (MFR) (g / 10 min)] Measured in accordance with ISO 1133 under the conditions of a test load of 2.16 kg and a test temperature of 230°C. [Decane Soluble Portion Amount (D sol ) and Insoluble Portion Amount (D insol )] Approximately 3 g (measured to the unit of 10 -4 g) of the sample [Component (A)] was placed in a glass measuring container, 500 ml of n-decane, and a small amount of a heat-resistant stabilizer soluble in n-decane were charged. While stirring with a stirrer under a nitrogen atmosphere, the temperature was raised to 150°C in 2 hours to dissolve the sample, and after holding at 150°C for 2 hours, it was gradually cooled to 23°C over 8 hours. The liquid containing the precipitated matter obtained was filtered under reduced pressure using a glass filter of the 25G-4 standard manufactured by Iwata Glass Co., Ltd. 100 ml of the filtrate was collected, dried under reduced pressure to obtain a part of the decane-soluble component, and this mass was measured to the unit of 10 -4 g (this mass was represented as x1(g) in the following formula). Using this measured value, the decane-soluble portion amount (Dsol ) and the amount of insoluble part (D insol ) was determined by the following formula. D sol (mass%) = 100×(500×x1) / (100×x2) D insol (mass%) = 100 - D sol

[0116] [Melting point peak] The endothermic curve of a differential scanning calorimeter (DSC) was obtained, and the temperature at the maximum peak position was determined as the melting point peak (Tm). Pyris 1 manufactured by PerkinElmer was used as the measuring instrument. The sample was packed in an aluminum pan, held at 30°C for 1 minute, then heated to 160°C at 500°C / min, and then held at 160°C for 5 minutes. After that, it was cooled to -30°C at 10°C / min, and then the melting point peak (Tm) was determined from the endothermic curve obtained when heating from -30°C to 160°C at 10°C / min. [Average particle diameter of inorganic filler] Based on JIS R1620 and JIS R1622, the particle size value at a cumulative amount of 50 mass% read from the particle size cumulative curve measured by the laser diffraction method was taken as the average particle diameter. [Aspect ratio of inorganic filler] Photographs were taken using an electron microscope, the major axis (particle diameter) and thickness of the powder were measured, the average value was obtained, and the aspect ratio was determined from the ratio of the average particle diameter to the average thickness. [Flexural modulus (MPa)] Measured under the following conditions in accordance with ASTM D790. Temperature: 23°C Test piece: 127 mm (length) × 12.7 mm (width) × 6.35 mm (thickness) Flexural speed: 30 mm / min Span: 100 cm

[0117] [IZOD impact strength (J / m)] The IZOD impact strength was measured under the following conditions in accordance with ASTM D256. Test piece: 63.5 mm (length) × 12.7 mm (width) × 3.2 mm (thickness) with notch Test temperature: -30°C [Coefficient of linear expansion (10 -5 / °C)] Evaluated by the TMA method (measurement range -30 to 80°C) in accordance with ASTM D 696. [Primerless adhesion test (90°C hot shear test)] ·Urethane-based adhesive In the primerless adhesion test, as the urethane-based adhesive, an adhesive prepared by mixing the following main agent component and the curing agent component immediately before adhesion was used. (Preparation of the main agent component) Using a stirrer, 42.4 parts by mass of urethane prepolymer, 1.7 parts by mass of isocyanurate of hexamethylene diisocyanate (Takenate D-170HN, manufactured by Mitsui Chemicals, Inc.), 1.3 parts by mass of a mixture of isocyanurate and allophanate of pentamethylene diisocyanate (Stabio D-376N, manufactured by Mitsui Chemicals, Inc.), 20.6 parts by mass of carbon black (#200MP, manufactured by Shin-Nippon Carbon Co., Ltd.), 18.3 parts by mass of calcium carbonate (Super S, manufactured by Maruo Calcium Co., Ltd.), 15.5 parts by mass of a plasticizer (diisononyl phthalate, manufactured by Jayplas Co., Ltd.) and 0.2 parts by mass of a catalyst (dimorpholinodiethyl ether, manufactured by San-Apro Co., Ltd.) were stirred and mixed to obtain the main agent component of the adhesive.

[0118] The urethane prepolymer was synthesized by mixing 700 g of polyoxypropylene diol (average molecular weight 2000), 300 g of polyoxypropylene triol (average molecular weight 3000), and 499 g of 4,4'-diisocyanatophenylmethane (molecular weight 250) (at this time NCO / OH = 2.0), adding 500 g of diisononyl phthalate, and stirring and reacting at 80°C for 12 hours in a nitrogen stream, and contained 2.10% of isocyanate groups. (Preparation of the curing agent component) Using a stirrer, 45.9 parts by mass of trifunctional polypropylene polyol (Excenol 1030, manufactured by Asahi Glass Co., Ltd.), 5.0 parts by mass of polybutadiene diol (Poly bd R-45HT, manufactured by Idemitsu Kosan Co., Ltd., hydroxyl value: 0.8 mol / kg), 2.0 parts by mass of terpineol (manufactured by Yasuhara Chemical Co., Ltd.), 45.8 parts by mass of calcium carbonate (Calfine 200, manufactured by Maruo Calcium Co., Ltd.), 1.0 part by mass of ion-exchanged water, and 0.1 part by mass of a catalyst (dimorpholinodiethyl ether, manufactured by San-Apro Ltd.) were stirred and mixed to obtain a curing agent component of the adhesive. ·Preparation of test pieces and surface treatment thereof Each polypropylene-based resin composition was injection molded at a resin temperature of 210°C and a mold temperature of 40°C using a mold cavity with a length of 350 mm, a width of 100 mm, and a thickness of 3 mm, and the obtained flat plate was cut into a shape of 100 mm × 25 mm × 3 mm to obtain a test piece for a primerless adhesion test.

[0119] Surface treatment (frame treatment) was performed on the surface of the obtained test piece. For the surface treatment, a frame treatment apparatus (FTS 201 manufactured by Arcogas) was used. The frame treatment apparatus can adjust the flow rates of the combustion gas and air.

[0120] As the surface treatment, the flow rate of air was fixed at 100 L / min, the flow rate of the combustion gas (propane gas) was adjusted to 3.7 L / min, the distance between the flat plate and the frame irradiation head was 40 mm, and the treatment speed was 800 mm / sec to produce a surface with a surface free energy of 42 dyn / cm (mN / m) (surface treatment state: low treatment). Similarly, a surface with a surface free energy of 52 dyn / cm (mN / m) was produced at a distance of 30 mm and 800 mm / sec (surface treatment state: medium treatment), and further, a surface with a surface free energy of 64 dyn / cm (mN / m) was produced at a distance of 10 mm and 800 mm / sec (surface treatment state: high treatment). ·Fabrication of laminated structure test pieces by primerless adhesion, 90°C hot shear test On each of the surface-treated test pieces obtained above, an adhesive layer made of an adhesive with an adhesive area of 25 mm (width) × 10 mm (length) and a thickness of 5 mm was formed without a primer. Glass (7.5 × 25 × 5 mm thick) was selected and used as the member on the other side through the adhesive layer, cured at room temperature conditions, and a laminated structure test piece in which a molded body made of a polypropylene-based resin composition, a resin cured layer obtained from the adhesive, and glass were laminated was obtained. After curing for 3 days at room temperature, the same surface treatment as described above was performed on the back surface of the resin base material side of each of the obtained laminated structure test pieces, and a cationic electrodeposited steel sheet with a thickness of 1 mm was bonded using an adhesive (WS-242 manufactured by Shika Hamatite Co., Ltd.). After further curing for 3 days at room temperature, in accordance with JIS K6850:1999, using a tensile testing machine, the glass was fixed as shown in the schematic diagram of FIG. 1, and the shear strength was measured at 90 °C under the condition of a tensile speed of 50 mm / min, and the average value of the four measurement values was determined as the hot shear test strength (MPa).

[0121] [Production Example 1] Preparation of Propylene-Ethylene Block Copolymer (A-1) (1) Preparation of Solid Titanium Catalyst Component 95.2 g of magnesium chloride anhydride, 442 mL of decane, and 390.6 g of 2-ethylhexyl alcohol were subjected to a heating reaction at 130 °C for 2 hours to form a homogeneous solution. 21.3 g of phthalic anhydride was added to this solution, and further stirring and mixing were carried out at 130 °C for 1 hour to dissolve the phthalic anhydride.

[0122] After cooling this homogeneous solution to room temperature, 75 mL of the homogeneous solution was dropwise charged into 200 mL of titanium tetrachloride maintained at -20 °C over 1 hour. After the charging was completed, the temperature of this mixed solution was raised to 110 °C over 4 hours. When it reached 110 °C, 5.22 g of diisobutyl phthalate (DIBP) was added, and the mixture was stirred and maintained at the same temperature for 2 hours.

[0123] After 2 hours of reaction, the solid part was collected by hot filtration, resuspended in 275 mL of titanium tetrachloride, and then heated again at 110 °C for 2 hours. After the reaction, the solid part was collected again by hot filtration and washed thoroughly with decane and hexane at 110 °C until no free titanium compound was detected in the solution.

[0124] The detection of this free titanium compound was confirmed by the following method. 10 mL of the supernatant of the above solid catalyst component was collected with a syringe and charged into a 100 mL Schlenk flask with branches that had been purged with nitrogen in advance. Next, the solvent hexane was dried under a nitrogen stream and further vacuum-dried for 30 minutes. To this, 40 mL of ion-exchanged water and 10 mL of (1+1) sulfuric acid were charged and stirred for 30 minutes. This aqueous solution was transferred through filter paper into a 100 mL volumetric flask. Subsequently, 1 mL of concentrated H3PO4 solution as a masking agent for iron(II) ions and 5 mL of 3% hydrogen peroxide aqueous solution as a color-developing reagent for titanium were added, and the volumetric flask was made up to 100 mL with ion-exchanged water. The volumetric flask was shaken, and after 20 minutes, the absorbance at 420 nm was observed using UV, and the free titanium was washed and removed until this absorption was no longer observed.

[0125] The solid titanium catalyst component prepared as described above was stored as a decane slurry, and a part of it was dried for the purpose of examining the catalyst composition. The composition of the solid titanium catalyst component thus obtained was 2.3 mass% titanium, 61 mass% chlorine, 19 mass% magnesium, and 12.5 mass% DIBP. (2) Preparation of prepolymerization catalyst 100 g of the above solid titanium catalyst component, 131 mL of triethylaluminum, 37.3 mL of diethylaminotriethoxysilane, and 14.3 L of heptane were inserted into an autoclave with a stirrer having an internal volume of 20 L, the internal temperature was maintained at 15-20 °C, 1000 g of propylene was inserted, and the reaction was carried out with stirring for 120 minutes. After the polymerization, the solid component was allowed to settle, and the supernatant was removed and washed twice with heptane. The obtained prepolymerization catalyst was resuspended in purified heptane, and the concentration was adjusted with heptane to a solid catalyst component concentration of 1.0 g / L to obtain a prepolymerization catalyst slurry. (3) Bulk polymerization Propylene was continuously fed at 43 kg / h, hydrogen at 256 NL / h, the prepolymerization catalyst slurry produced in (2) above as a solid titanium catalyst component at 0.49 g / h, triethylaluminum at 4.5 mL / h, and diethylaminotriethoxysilane at 1.8 mL / h to a jacketed circulation type tubular polymerizer with an internal volume of 58 L, and polymerization was carried out in a full liquid state in the absence of a gas phase. The temperature of the tubular polymerizer was 70 °C and the pressure was 3.57 MPa / G. The resulting slurry was sent to a vessel polymerizer with a stirrer having an internal volume of 100 L, and further polymerization was carried out. Propylene was fed to the polymerizer at 45 kg / h and hydrogen was fed so that the hydrogen concentration in the gas phase part became 8.8 mol%, and polymerization was carried out at a polymerization temperature of 68 °C and a pressure of 3.36 MPa / G.

[0126] Next, the resulting slurry was transferred to a transfer pipe with an internal volume of 2.4 L, the slurry was gasified, and gas-solid separation was carried out. Thereafter, polypropylene homopolymer powder was sent to a gas phase polymerizer with an internal volume of 480 L, and ethylene / propylene block copolymerization was carried out. Propylene, ethylene, and hydrogen were continuously fed so that the gas composition in the gas phase polymerizer became ethylene / (ethylene + propylene) = 0.20 (molar ratio) and hydrogen / ethylene = 0.0031 (molar ratio), and polymerization was carried out at a polymerization temperature of 70 °C and a pressure of 1.40 MPa / G.

[0127] Next, the obtained propylene-based block copolymer was vacuum dried at 80 °C. The MFR (230 °C, 2.16 kg load) of the propylene-ethylene block copolymer (A-1) thus obtained was 80 g / 10 min, the amount of the decane-soluble part (propylene-ethylene copolymer component) was 7% by mass, the amount of the decane-insoluble part (propylene homopolymer component) was 93% by mass, and the limiting viscosity [η] of the decane-soluble part was 7.5 dl / g.

[0128] [Production Example 2] Preparation of Propylene Homopolymer (B-1) A solid titanium catalyst component was obtained in the same manner as in the preparation of the solid titanium catalyst component in (1) of Production Example 1. (2) Production of Prepolymerization Catalyst 100 g of a solid titanium catalyst component, 39.3 mL of triethylaluminum, and 100 L of heptane were inserted into an autoclave with a stirrer having an internal volume of 200 L. The internal temperature was maintained at 15 to 20 °C, and 600 g of propylene was inserted. The reaction was carried out with stirring for 60 minutes to obtain a prepolymerization catalyst slurry. (3) Bulk polymerization Propylene was continuously fed at 43 kg / hour, hydrogen was fed at 177 NL / hour, 0.58 g / hour of the prepolymerization catalyst slurry prepared in (2) as a solid titanium catalyst component, 3.1 ml / hour of triethylaluminum, and 3.3 ml / hour of dicyclopentyldimethoxysilane into a jacketed circulation type tubular polymerization reactor having an internal volume of 58 L, and polymerization was carried out in a full liquid state in the absence of a gas phase. The temperature of the tubular polymerization reactor was 70 °C, and the pressure was 3.53 MPa / G. The obtained slurry was sent to a vessel polymerization reactor with a stirrer having an internal volume of 100 L, and further polymerization was carried out. Propylene was fed to the polymerization reactor at 45 kg / hour, and hydrogen was fed so that the hydrogen concentration in the gas phase part became 3.2 mol%. Polymerization was carried out at a polymerization temperature of 70 °C and a pressure of 3.28 MPa / G. Next, the obtained propylene homopolymer was vacuum dried at 80 °C. The MFR (230 °C, 2.16 kg load) of the propylene homopolymer (B-1) thus obtained was 30 g / 10 minutes.

[0129] [Production Example 3] Preparation of propylene homopolymer (B-2) First, a prepolymerization catalyst slurry was obtained in the same manner as in (1) the preparation of the solid titanium catalyst component and (2) the production of the prepolymerization catalyst in Production Example 1. (3) Bulk polymerization Propylene was continuously fed at 131 kg / hour, 0.70 g / hour of the prepolymerization catalyst slurry as a transition metal catalyst component, 19.6 mL / hour of triethylaluminum, and 4.2 mL / hour of diethylaminotriethoxysilane into a vessel polymerization reactor with a stirrer having an internal volume of 1000 L, and hydrogen was fed so that the hydrogen concentration in the gas phase part became 5.3 mol%. Polymerization was carried out at a polymerization temperature of 75 °C and a pressure of 3.5 MPa / G.

[0130] The obtained slurry was sent to a 500 L stirred vessel polymerization reactor, and further polymerization was carried out. Propylene was supplied to the polymerization reactor at 30 kg / hour, and hydrogen was supplied so that the hydrogen concentration in the gas phase was 3.9 mol%. Polymerization was carried out at a polymerization temperature of 74.5 °C and a pressure of 3.4 MPa / G.

[0131] Next, the obtained slurry was sent to a 500 L stirred vessel polymerization reactor, and further polymerization was carried out. Propylene was supplied to the polymerization reactor at 20 kg / hour, and hydrogen was supplied so that the hydrogen concentration in the gas phase was 3.4 mol%. Polymerization was carried out at a polymerization temperature of 73 °C and a pressure of 3.4 MPa / G.

[0132] Next, the obtained slurry was deactivated and vaporized, and then gas-solid separation was carried out. The obtained propylene homopolymer was vacuum dried at 80 °C. The MFR (230 °C, 2.16 kg load) of the propylene homopolymer (B-2) thus obtained was 210 g / 10 minutes.

[0133] [Ethylene·α-olefin copolymer] As the ethylene·α-olefin copolymer (C-1), Tafmer (registered trademark) A4050S manufactured by Mitsui Chemicals, Inc. (ethylene content = 80 mol%, 1-butene content = 20 mol%, MFR (230 °C, 2.16 kg load) = 7 g / 10 minutes, density = 0.862 g / cm 3 , melting point peak < 50 °C) was used.

[0134] As the ethylene·α-olefin copolymer (C-2), Tafmer (registered trademark) A1050S manufactured by Mitsui Chemicals, Inc. (ethylene content = 80 mol%, 1-butene content = 20 mol%, MFR (230 °C, 2.16 kg load) = 2 g / 10 minutes, density = 0.862 g / cm 3 , melting point peak < 50 °C) was used.

[0135] As the ethylene·α-olefin copolymer (C-3), ENGAGE (registered trademark) 11547, a polyolefin elastomer manufactured by The Dow Chemical Company (MFR (230 °C, 2.16 kg load) = 9 g / 10 minutes, density = 0.866 g / cm 3, a melting point peak of 120 °C was used.

[0136] [Inorganic filler] As the inorganic filler (D-1), talc having the following characteristics was used. (D-1): Talc, average particle size (laser diffraction method) = 6.0 μm, aspect ratio (SEM measurement) = 7.0

[0137] [Examples 1-2, Comparative Examples 1-2] The propylene-based polymer (A), propylene homopolymer (B), ethylene·α-olefin copolymer (C) and inorganic filler (D) were mixed in the compounding amounts shown in Table 1, and were extruded by a twin-screw extruder (manufactured by Japan Steel Works, Ltd., TEX (registered trademark) 30α) under the conditions of a cylinder temperature of 180 °C, a screw rotation of 750 rpm, and an extrusion rate of 60 kg / h to obtain a polypropylene-based resin composition. The melt flow rate (230 °C, 2.16 kg load) of each obtained polypropylene-based resin composition is shown in Table 1.

[0138] Each obtained polypropylene-based resin composition was injection-molded at a resin temperature of 210 °C and a mold temperature of 40 °C using a mold cavity with a length of 350 mm, a width of 100 mm, and a thickness of 3 mm to obtain a flat plate, which was cut into a shape of 100 mm×50 mm×3 mm to obtain a molded test piece for primerless adhesion test. Also, by injection molding and cutting at the same resin temperature and mold temperature, a molded test piece for measurement with the above-described shape was obtained.

[0139] Using each obtained molded test piece, the flexural modulus, IZOD impact strength and linear expansion coefficient were measured by the above-described test methods. Also, the 90 °C hot shear test strength was measured by the above-described primerless adhesion test. The results are shown in Table 1.

[0140]

Table 1

[0141] The polypropylene-based resin composition and the molded article thereof according to the present invention can be suitably used for applications such as automotive interior materials such as door trims, instrument panels, ceilings, console boxes, pillars, glove boxes, etc.; automotive exterior members such as bumpers, side guards, air spoilers, side protectors, fenders, door panels, back doors, etc., industrial parts such as home appliance parts and building materials.

Claims

1. 5 to 22 parts by mass of a propylene-based polymer (A) having a melt flow rate (at 230 ° C., 2.16 kg load) of 50 to 150 g / 10 min and a decane-soluble portion of 6 to 15% by mass, 20 to 30 parts by mass of a propylene homopolymer (B) having a melt flow rate (at 230 ° C., 2.16 kg load) of 10 to 500 g / 10 min, A random copolymer of ethylene and an α-olefin having 4 to 8 carbon atoms, with a density of 0.850 to 0.880 g / cm 3 , 23 to 30 parts by mass of an ethylene / α-olefin copolymer (C) having a melt flow rate (at 230 ° C., 2.16 kg load) of 0.5 to 30 g / 10 min and a melting point peak of 110 ° C. or higher, and 30 to 40 parts by mass of an inorganic filler (D) [However, the total amount of components (A) to (D) is 100 parts by mass.] A polypropylene-based resin composition containing the same.

2. The polypropylene-based resin composition according to claim 1, wherein the propylene-based polymer (A) is a block copolymer of propylene and ethylene, and the intrinsic viscosity [η] of the decane-soluble portion of the copolymer is 2 to 9 dl / g.

3. The polypropylene-based resin composition according to claim 1, wherein the inorganic filler (D) is talc and the aspect ratio thereof is 3 or more and less than 15.

4. The polypropylene-based resin composition according to claim 1, wherein in a primerless adhesion test, the hot shear test strength at 90 ° C. exceeds 1.5 MPa.

5. The polypropylene-based resin composition according to claim 1, which is used for an automotive exterior member.

6. A molded article comprising the polypropylene-based resin composition according to any one of claims 1 to 5.

7. The molded article according to claim 6, which is an injection molded article or a press molded article.

8. The molded body according to claim 6, which is an automotive exterior member.

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