Polyolefin resin composition, and, compact

Abstract

To provide a polyolefin resin composition capable of obtaining a compact relatively excellent in tensile strength, while containing a plant-derived filler, and, a compact containing the polyolefin resin composition.SOLUTION: The polyolefin resin composition according to the present invention contains polyolefin resin (A), modified polyolefin resin (B), plant-derived filler (C), hydrophilic resin (D) having a hydroxyl group, and a compound (E) that crosslinks hydroxyl groups, with the total content of the (A), (B), (C), (D), and (E) being 100 mass%, a content of polyolefin resin (A) is 1 to 96.4 mass% or less, the content of modified polyolefin resin (B) is 1 to 20 mass% or less, the content of plant-derived filler (C) is 1 to 80 mass% or less, the content of hydrophilic resin (D) having a hydroxyl group is 1 to 30 mass% or less, and the content of compound (E) that crosslinks hydroxyl groups is 0.1 to 10 mass% or less.SELECTED DRAWING: None

Description

Technical Field

[0001] The present invention relates to a polyolefin resin composition and a molded article containing the polyolefin resin composition.

Background Art

[0002] Molded articles containing polyolefin resin compositions are used in industrial parts such as household goods, automotive parts, and electrical parts, as well as daily necessities and miscellaneous goods. Fillers are compounded in such polyolefin resin compositions in order to enhance mechanical strength and the like. Examples of such fillers include inorganic powders such as talc and silica; cellulose powders such as wood powder and bamboo powder; fibrous fillers such as natural fibers, glass fibers, and carbon fibers.

[0003] In recent years, from the viewpoints of reducing environmental impact and carbon neutrality, polyolefin resin compositions containing plant-derived fillers such as cellulose powders like wood powder and bamboo powder have attracted attention. As such a polyolefin resin composition, for example, Patent Document 1 discloses a cellulose resin composite containing cellulose, a polypropylene resin, an acid-modified polyolefin resin, and polyvinyl alcohol.

Prior Art Documents

Patent Documents

[0004]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0005] However, the molded article containing the cellulose resin composite described in Patent Document 1 has insufficient mechanical strength, particularly tensile strength, and there is room for improvement.

[0006] The present invention has been made in view of such problems, and an object thereof is to provide a polyolefin resin composition capable of obtaining a molded article having relatively excellent tensile strength while containing a plant-derived filler, and a molded article containing the polyolefin resin composition.

Means for Solving the Problems

[0007] The polyolefin resin composition according to the present invention contains a polyolefin resin (A), a modified polyolefin resin (B), a plant-derived filler (C), a hydrophilic resin (D) having a hydroxyl group, and a compound (E) that crosslinks the hydroxyl group. Assuming that the total content of (A), (B), (C), (D) and (E) is 100% by mass, the content of the polyolefin resin (A) is 1% by mass or more and 96.4% by mass or less, the content of the modified polyolefin resin (B) is 1% by mass or more and 20% by mass or less, the content of the plant-derived filler (C) is 1% by mass or more and 80% by mass or less, the content of the hydrophilic resin (D) having a hydroxyl group is 1% by mass or more and 30% by mass or less, the content of the compound (E) that crosslinks the hydroxyl group is 0.1% by mass or more and 10% by mass or less.

[0008] The molded article according to the present invention contains the polyolefin resin composition.

Effects of the Invention

[0009] According to the present invention, it is possible to provide a polyolefin resin composition capable of obtaining a molded article having relatively excellent tensile strength while containing a plant-derived filler, and a molded article containing the polyolefin resin composition.

Modes for Carrying Out the Invention

[0010] Hereinafter, embodiments of the present invention will be described, but the present invention is not limited to the following embodiments.

[0011] 1. Polyolefin resin composition The polyolefin resin composition according to this embodiment includes a polyolefin resin (A), a modified polyolefin resin (B), a plant-derived filler (C), a hydrophilic resin (D) having a hydroxyl group, and a compound (E) that crosslinks the hydroxyl group.

[0012] [Polyolefin resin (A)] The polyolefin resin (A) is a resin containing an olefin polymer. In this specification, the polyolefin resin (A) means an unmodified polyolefin resin.

[0013] Examples of the polyolefin resin (A) include polyethylene resins, polypropylene resins, and the like. Among these, from the viewpoint of obtaining a molded article having relatively excellent tensile strength while containing a plant-derived filler, the polyolefin resin (A) is preferably a polypropylene resin.

[0014] [<Polypropylene resin>] The polypropylene resin is a resin containing a propylene polymer.

[0015] The propylene polymer is a polymer containing more than 50% by mass of monomer units derived from propylene. Examples of the propylene polymer include a propylene homopolymer, a random copolymer of propylene and a monomer other than propylene, a heterophasic propylene polymerization material, and the like. The polypropylene resin may contain only one type of propylene polymer or two or more types.

[0016] From the viewpoint of improving the rigidity and impact resistance of the molded article, the polypropylene resin preferably contains at least one selected from the group consisting of a propylene homopolymer and a heterophasic propylene polymerization material as the propylene polymer, and more preferably contains a heterophasic propylene polymerization material.

[0017] The propylene homopolymer can be produced, for example, by performing a polymerization step of polymerizing propylene using a polymerization catalyst.

[0018] Examples of the polymerization catalyst include Ziegler catalysts; Ziegler-Natta catalysts; catalysts containing a compound of a Group 4 transition metal of the periodic table having a cyclopentadienyl ring and an alkylaluminoxane; catalysts containing a compound of a Group 4 transition metal of the periodic table having a cyclopentadienyl ring, a compound that reacts with the transition metal compound to form an ionic complex, and an organoaluminum compound; and modified catalysts in which catalyst components (a compound of a Group 4 transition metal of the periodic table having a cyclopentadienyl ring, a compound that forms an ionic complex, an organoaluminum compound, etc.) are supported on inorganic particles (silica, clay minerals, etc.).

[0019] Examples of the polymerization catalyst include the catalysts described in JP-A-61-218606, JP-A-5-194685, JP-A-7-216017, JP-A-9-316147, JP-A-10-212319, JP-A-2004-182981, JP-A-2010-168545, JP-A-2011-246699, etc.

[0020] In addition, a polymer obtained by prepolymerizing propylene in the presence of the polymerization catalyst can also be used as the polymerization catalyst.

[0021] Examples of the polymerization method include bulk polymerization, solution polymerization, gas-phase polymerization, etc. Here, bulk polymerization refers to a method of performing polymerization using a liquid olefin as a medium at the polymerization temperature. Solution polymerization refers to a method of performing polymerization in an inert hydrocarbon solvent such as propane, butane, isobutane, pentane, hexane, heptane, octane, etc. Gas-phase polymerization refers to a method of polymerizing a monomer in a gaseous state using the gaseous monomer as a medium in that medium.

[0022] Examples of the polymerization mode include batch type, continuous type, and combinations thereof. The polymerization mode may be a multi-stage type in which a plurality of polymerization reaction tanks are connected in series.

[0023] From the viewpoints of industrial and economic advantages, the polymerization method is preferably a continuous gas-phase polymerization method, or a bulk-gas phase polymerization method that continuously performs a bulk polymerization method and a gas-phase polymerization method.

[0024] Various conditions in the polymerization step (polymerization conditions such as polymerization temperature, polymerization pressure, monomer concentration, catalyst input amount, polymerization time, etc.) may be appropriately determined according to the molecular structure of the target polymer.

[0025] In the method for producing a propylene homopolymer, other steps may be carried out before or after the polymerization step. For example, after the polymerization step, in order to remove residual solvents contained in the polymer, ultra-low molecular weight oligomers by-produced during production, etc., the polymer may be dried at a temperature not higher than the melting temperature of the polymer as necessary. Examples of the drying method include the methods described in JP-A-55-75410, Japanese Patent No. 2565753, etc.

[0026] The random copolymer of propylene and a monomer other than propylene contains a monomer unit derived from propylene and a monomer unit derived from a monomer other than propylene. In the random copolymer, the content of the monomer unit derived from a monomer other than propylene is preferably 0.01% by mass or more and 30% by mass or less, more preferably 0.1% by mass or more and 20% by mass or less, based on 100% by mass of the total mass of the copolymer.

[0027] Examples of the monomer other than propylene include ethylene, α-olefins having 4 to 12 carbon atoms, etc. In this specification, an α-olefin is an aliphatic unsaturated hydrocarbon having a carbon-carbon unsaturated double bond at the α-position. Examples of the α-olefin having 4 to 12 carbon atoms include 1-butene, 1-pentene, 1-hexene, 1-heptene, 1-octene, 1-nonene, 1-decene, 1-dodecene, 4-methyl-1-pentene, 4-methyl-1-hexene, etc.

[0028] Monomers other than propylene are preferably at least one selected from the group consisting of ethylene and α-olefins having 4 to 10 carbon atoms, more preferably at least one selected from the group consisting of ethylene, 1-butene, 1-hexene, and 1-octene, and still more preferably at least one selected from the group consisting of ethylene and 1-butene.

[0029] Examples of the random copolymer of propylene and a monomer other than propylene include a propylene-ethylene random copolymer, a propylene-1-butene random copolymer, a propylene-1-hexene random copolymer, a propylene-1-octene random copolymer, a propylene-ethylene-1-butene random copolymer, a propylene-ethylene-1-hexene random copolymer, a propylene-ethylene-1-octene random copolymer, and the like.

[0030] The random copolymer of propylene and a monomer other than propylene can be produced, for example, by polymerizing propylene and a monomer other than propylene according to the polymerization catalyst, polymerization method, polymerization mode, and polymerization conditions that can be used in the production of the above-mentioned propylene homopolymer.

[0031] The heterophasic propylene polymerization material is a mixture containing a polymer I containing monomer units derived from propylene and a polymer II containing monomer units derived from at least one α-olefin selected from the group consisting of ethylene and α-olefins having 4 to 12 carbon atoms and monomer units derived from propylene.

[0032] The heterophasic propylene polymerization material can be produced, for example, by carrying out a first polymerization step of polymerizing polymer I and a second polymerization step of polymerizing polymer II. These polymerization steps can be carried out according to the polymerization catalyst, polymerization method, polymerization mode, and polymerization conditions that can be used in the production of the above-mentioned propylene homopolymer.

[0033] The heterophasic propylene polymerization material may have a total of the polymer I and the polymer II contained in the heterophasic propylene polymerization material of 100% by mass based on 100% by mass of the total mass of the heterophasic propylene polymerization material.

[0034] The polymer I may contain 70% by mass or more of monomer units derived from propylene (where the total mass of the polymer I is taken as 100% by mass). The polymer I may be, for example, a propylene homopolymer, or may contain monomer units derived from monomers other than propylene. When the polymer I contains monomer units derived from monomers other than propylene, the content is usually 0.01% by mass or more and 30% by mass or less based on 100% by mass of the total mass of the polymer I.

[0035] Examples of monomers other than propylene include ethylene and α-olefins having 4 or more carbon atoms. Examples of α-olefins having 4 or more carbon atoms include 1-butene, 1-pentene, 1-hexene, 1-heptene, 1-octene, 1-nonene, 1-decene, 1-dodecene, 4-methyl-1-pentene, 4-methyl-1-hexene, and the like.

[0036] The monomer other than propylene is preferably at least one selected from the group consisting of ethylene and α-olefins having 4 to 10 carbon atoms, more preferably at least one selected from the group consisting of ethylene, 1-butene, 1-hexene, and 1-octene, and still more preferably at least one selected from the group consisting of ethylene and 1-butene.

[0037] Examples of the polymer I containing monomer units derived from monomers other than propylene include propylene-ethylene copolymers, propylene-1-butene copolymers, propylene-1-hexene copolymers, propylene-1-octene copolymers, propylene-ethylene-1-butene copolymers, propylene-ethylene-1-hexene copolymers, propylene-ethylene-1-octene copolymers, and the like.

[0038] Polymer I is preferably a propylene homopolymer, a propylene-ethylene copolymer, a propylene-1-butene copolymer, or a propylene-1-hexene copolymer, more preferably a propylene homopolymer.

[0039] The content of Polymer I is usually 30% by mass or more and 99% by mass or less, preferably 50% by mass or more and 95% by mass or less, more preferably 60% by mass or more and 90% by mass or less, based on 100% by mass of the total mass of the heterophasic propylene polymerization material.

[0040] As described above, Polymer II contains monomer units derived from at least one α-olefin selected from the group consisting of ethylene and α-olefins having 4 to 12 carbon atoms and monomer units derived from propylene. Examples of the α-olefins having 4 to 12 carbon atoms include 1-butene, 1-pentene, 1-hexene, 1-heptene, 1-octene, 1-nonene, 1-decene, 1-dodecene, 4-methyl-1-pentene, 4-methyl-1-hexene, and the like.

[0041] Polymer II preferably contains 30% by mass or more of monomer units derived from at least one α-olefin selected from the group consisting of ethylene and α-olefins having 4 to 12 carbon atoms and contains monomer units derived from propylene (where the total mass of Polymer II is 100% by mass).

[0042] In Polymer II, the content of monomer units derived from at least one α-olefin selected from the group consisting of ethylene and α-olefins having 4 to 12 carbon atoms is usually 1% by mass or more and 80% by mass or less, preferably 20% by mass or more and 70% by mass or less, more preferably 30% by mass or more and 60% by mass or less (where the total mass of Polymer II is 100% by mass).

[0043] In the polymer II, at least one α-olefin selected from the group consisting of ethylene and α-olefins having 4 to 12 carbon atoms is preferably at least one selected from the group consisting of ethylene and α-olefins having 4 to 10 carbon atoms, more preferably at least one selected from the group consisting of ethylene, 1-butene, 1-hexene, 1-octene, and 1-decene, and still more preferably at least one selected from the group consisting of ethylene and 1-butene.

[0044] Examples of the polymer II include propylene-ethylene copolymer, propylene-ethylene-1-butene copolymer, propylene-ethylene-1-hexene copolymer, propylene-ethylene-1-octene copolymer, propylene-ethylene-1-decene copolymer, propylene-1-butene copolymer, propylene-1-hexene copolymer, propylene-1-octene copolymer, propylene-1-decene copolymer, and the like. Among these, the polymer II is preferably a propylene-ethylene copolymer, a propylene-1-butene copolymer, or a propylene-ethylene-1-butene copolymer, and more preferably a propylene-ethylene copolymer.

[0045] The content of the polymer II is usually 1% by mass or more and 70% by mass or less, preferably 5% by mass or more and 50% by mass or less, and more preferably 10% by mass or more and 40% by mass or less with respect to 100% by mass of the total mass of the heterophasic propylene polymerization material.

[0046] Examples of heterophasic propylene polymerization materials include, for example, (propylene)-(propylene-ethylene) polymerization materials, (propylene)-(propylene-ethylene-1-butene) polymerization materials, (propylene)-(propylene-ethylene-1-hexene) polymerization materials, (propylene)-(propylene-ethylene-1-octene) polymerization materials, (propylene)-(propylene-1-butene) polymerization materials, (propylene)-(propylene-1-hexene) polymerization materials, (propylene)-(propylene-1-octene) polymerization materials, (propylene)-(propylene-1-decene) polymerization materials, (propylene-ethylene)-(propylene-ethylene) polymerization materials, (propylene-ethylene)-(propylene-ethylene-1-butene) polymerization materials, (propylene-ethylene)-(propylene-ethylene-1-hexene) polymerization materials, (propylene-ethylene)-(propylene-ethylene-1-octene) polymerization materials, (propylene-ethylene)-(propylene-ethylene-1-decene) polymerization materials, (propylene-ethylene)-(propylene-1-butene) polymerization materials, (propylene-ethylene)-(propylene-1-hexene) polymerization materials, (propylene-ethylene)-(propylene-1-octene) polymerization materials, (propylene-ethylene)-(propylene-1-decene) polymerization materials, (propylene-1-butene)-(propylene-ethylene) polymerization materials, (propylene-1-butene)-(propylene-ethylene-1-butene) polymerization materials, (propylene-1-butene)-(propylene-ethylene-1-hexene) polymerization materials, (propylene-1-butene)-(propylene-ethylene-1-octene) polymerization materials, (propylene-1-butene)-(propylene-ethylene-1-decene) polymerization materials, (propylene-1-butene)-(propylene-1-butene) polymerization materials, (propylene-1-butene)-(propylene-1-hexene) polymerization materials, (propylene-1-butene)-(propylene-1-octene) polymerization materials, (propylene-1-butene)-(propylene-1-decene) polymerization materials, (propylene-1-hexene)-(propylene-1-hexene) polymerization materials, (propylene-1-hexene)-(propylene-1-octene) polymerization materials, (propylene-1-hexene)-(propylene-1-decene) polymerization materials, (propylene-1-octene)-(propylene-1-octene) polymerization materials,Examples include (propylene-1-octene)-(propylene-1-decene) polymerization materials, etc.

[0047] Here, the description of “(propylene)-(propylene-ethylene) polymerization material” means a heterophasic propylene polymerization material in which “polymer I is a propylene homopolymer and polymer II is a propylene-ethylene copolymer”. The same applies to other similar expressions.

[0048] The heterophasic propylene polymerization material is preferably a (propylene)-(propylene-ethylene) polymerization material, a (propylene)-(propylene-ethylene-1-butene) polymerization material, a (propylene-ethylene)-(propylene-ethylene) polymerization material, a (propylene-ethylene)-(propylene-ethylene-1-butene) polymerization material, or a (propylene-1-butene)-(propylene-1-butene) polymerization material, and more preferably a (propylene)-(propylene-ethylene) polymerization material.

[0049] From the viewpoint of improving the molding processability of the polypropylene resin composition, the melt flow rate (MFR) of the propylene polymer is preferably 1 g / 10 min or more and 300 g / 10 min or less, and more preferably 10 g / 10 min or more and 200 g / 10 min or less.

[0050] The melt flow rate (MFR) of the propylene polymer is measured by Method A under the conditions of a temperature of 230 °C and a load of 2.16 kg in accordance with the methods specified in JIS K7210-1:2014 and K7210-2:2014.

[0051] <Polyethylene resin> The polyethylene resin is a resin containing an ethylene polymer.

[0052] The ethylene-based polymer is a polymer containing more than 50% by mass of monomer units derived from ethylene. Examples of the ethylene-based polymer include, for example, an ethylene homopolymer, a copolymer of ethylene and an α-olefin, a copolymer of an α-olefin substituted with an alicyclic compound and ethylene, and the like. Further, the ethylene-based polymer may be a mixture of an ethylene homopolymer and a copolymer of ethylene and an α-olefin. Further, the amount of monomer units derived from the α-olefin in the ethylene-based polymer is not particularly limited, and may be, for example, 4.0% by mass or more and 20% by mass or less.

[0053] Examples of the ethylene homopolymer include high-pressure low-density polyethylene (LDPE) produced by high-pressure radical polymerization using a radical initiator. High-pressure low-density polyethylene (LDPE) is a polymer in which ethylene repeating units are randomly bonded with a branched structure. Further, high-pressure low-density polyethylene (LDPE) has, for example, a density of 910 to 935 kg / m 3 and may be.

[0054] Examples of the copolymer of ethylene and an α-olefin include linear low-density polyethylene having crystallinity, and an elastomer of a copolymer of ethylene and an α-olefin having low crystallinity and rubber-like elastic properties.

[0055] The density of the linear low-density polyethylene may be, for example, 900 to 940 kg / m 3 and may be. The density of the elastomer of the copolymer of ethylene and an α-olefin may be, for example, 860 to 900 kg / m 3 and may be.

[0056] Examples of the α-olefin include α-olefins having 3 to 10 carbon atoms. Examples of the α-olefin having 3 to 10 carbon atoms include propylene, 1-butene, 1-pentene, 1-hexene, 4-methyl-1-pentene, 1-octene, 1-decene, 3-methyl-1-butene, etc. Preferably, it is an α-olefin having 4 to 10 carbon atoms, and more preferably 1-butene, 1-hexene or 1-octene.

[0057] Examples of the copolymer of ethylene and an α-olefin include ethylene-1-butene copolymer, ethylene-1-hexene copolymer, ethylene-1-octene copolymer, ethylene-1-decene copolymer, ethylene-(3-methyl-1-butene) copolymer, etc. Further, the copolymer of ethylene and an α-olefin may be a single one of these or a mixture of two or more.

[0058] Examples of the α-olefin substituted with an alicyclic compound include vinylcyclohexane, etc.

[0059] The melt flow rate (MFR) of the ethylene-based polymer is preferably 0.5 g / 10 min or more and 50 g / 10 min or less, more preferably 1 g / 10 min or more and 30 g / 10 min or less, and still more preferably 1 g / 10 min or more and 20 g / 10 min or less.

[0060] The melt flow rate (MFR) of the ethylene-based polymer is measured by Method A under the conditions of a temperature of 190 °C and a load of 2.16 kg in accordance with the methods specified in JIS K7210-1:2014 and K7210-2:2014.

[0061] The ethylene-based polymer can be produced by a known polymerization method using a known polymerization catalyst.

[0062] Examples of the coordination catalyst include homogeneous catalyst systems typified by metallocene catalysts, Ziegler catalyst systems, Ziegler-Natta catalyst systems, and the like. Examples of the homogeneous catalyst system include a catalyst system composed of a Group 4 transition metal compound having a cyclopentadienyl ring and an alkylaluminoxane, or a catalyst system composed of a Group 4 transition metal compound having a cyclopentadienyl ring, a compound that reacts with the transition metal compound to form an ionic complex, and an organoaluminum compound, a catalyst system in which catalyst components such as a Group 4 transition metal compound having a cyclopentadienyl ring, a compound that forms an ionic complex, and an organoaluminum compound are supported and modified on inorganic particles such as silica and clay minerals, a prepolymerization catalyst system prepared by prepolymerizing ethylene or α-olefin in the presence of the above catalyst system, and the like.

[0063] In addition, a radical initiator can be used as the polymerization catalyst for high-pressure low-density polyethylene (LDPE).

[0064] From the viewpoint of obtaining a molded article having relatively excellent tensile strength while containing the plant-derived filler, the content of the polyolefin resin (A) is 1% by mass or more and 96.4% by mass or less, preferably 15% by mass or more and 80% by mass or less, and more preferably 50% by mass or more and 75% by mass or less, with the total content of (A), (B), (C), (D) and (E) being 100% by mass. When the polyolefin resin (A) contains two or more olefin polymers, the content of the polyolefin resin (A) is the total content thereof.

[0065] [Modified polyolefin resin (B)] The modified polyolefin resin (B) is a resin containing a modified polyolefin polymer.

[0066] Examples of the modified polyolefin resin (B) include modified polyethylene resins, modified polypropylene resins, and the like. Among these, from the viewpoint of obtaining a molded article having relatively excellent tensile strength while containing a plant-derived filler, the modified polyolefin resin (B) is preferably a modified polypropylene resin.

[0067] Examples of the modified polyolefin polymer include acid-modified polyolefin polymers, hydroxyl group-modified polyolefin polymers, epoxy-modified polyolefin polymers, carbodiimide-modified polyolefin polymers, amine-modified polyolefin polymers, acrylic-modified polyolefin polymers, polyoxyethylene-modified polyolefin polymers, and the like. Among these, from the viewpoint of obtaining a molded article having relatively excellent tensile strength while containing a plant-derived filler, the modified polyolefin polymer is preferably at least one selected from the group consisting of acid-modified polyolefin polymers, hydroxyl group-modified polyolefin polymers, epoxy-modified polyolefin polymers, carbodiimide-modified polyolefin polymers, amine-modified polyolefin polymers, and acrylic-modified polyolefin polymers, and more preferably at least one selected from the group consisting of acid-modified polyolefin polymers, hydroxyl group-modified polyolefin polymers, epoxy-modified polyolefin polymers, and carbodiimide-modified polyolefin polymers. Note that the modified polyolefin resin (B) may contain only one type of modified polyolefin polymer or two or more types. As one aspect, the polyolefin resin composition in the present embodiment contains at least one selected from the group consisting of the acid-modified polyolefin polymer, hydroxyl group-modified polyolefin polymer, epoxy-modified polyolefin polymer, and carbodiimide-modified polyolefin polymer as the modified polyolefin resin (B).

[0068] The acid-modified polyolefin polymer is the one shown in the following (1) or (2), that is, it has a monomer unit (modifying group) derived from at least one of an unsaturated carboxylic acid and its derivative. (1) A homopolymer of an olefin, a random copolymer of at least two olefins, or a heterophasic olefin polymerization material obtained by copolymerizing at least two olefins after homopolymerizing an olefin, to which at least one of an unsaturated carboxylic acid and its derivative is subjected to a graft reaction or a terminal reaction. (2) A copolymer of at least one olefin and at least one of an unsaturated carboxylic acid and its derivative.

[0069] Note that the olefin in the above (1) and (2) may be the same as or different from the olefin constituting the olefin polymer in the polyolefin resin (A).

[0070] Examples of the unsaturated carboxylic acid include maleic acid, fumaric acid, itaconic acid, acrylic acid, methacrylic acid, etc. Examples of the derivative of the unsaturated carboxylic acid include unsaturated carboxylic acid anhydrides such as maleic anhydride and itaconic anhydride; unsaturated carboxylic acid esters such as methyl acrylate, ethyl acrylate, butyl acrylate, glycidyl acrylate, methyl methacrylate, ethyl methacrylate, butyl methacrylate, glycidyl methacrylate, monoethyl maleate, diethyl maleate, monomethyl fumarate, dimethyl fumarate, etc.; unsaturated carboxylic acid amides such as acrylamide, methacrylamide, monoamide maleic acid, diamide maleic acid, monoamide fumaric acid, etc.; unsaturated carboxylic acid imides such as maleimide and N-butyl maleimide; and metal salts of unsaturated carboxylic acids such as sodium methacrylate. Note that the unsaturated carboxylic acid may be one generated by dehydrating citric acid, malic acid, etc. in the step of grafting onto the polyolefin. At least one of the unsaturated carboxylic acid and its derivative is preferably maleic anhydride, glycidyl acrylate, or glycidyl methacrylate.

[0071] The acid-modified polyolefin polymer is, in one aspect, the one shown in the following (1') or (2'). An olefin polymer containing 70% by mass or more, preferably 80% by mass or more of monomer units derived from at least one olefin selected from ethylene and propylene, to which maleic anhydride has been subjected to a graft reaction or a terminal reaction. (2’) A copolymer of at least one olefin selected from ethylene and propylene and glycidyl methacrylate or maleic anhydride.

[0072] Examples of the acid-modified polyolefin polymer include maleic anhydride-modified polypropylene, maleic anhydride-modified polyethylene, maleic acid-modified polypropylene, itaconic acid-modified polypropylene, methacrylic acid-modified polypropylene, glycidyl acrylate-modified polypropylene, glycidyl methacrylate-modified polypropylene, and the like. Among these, the acid-modified polyolefin polymer is preferably maleic anhydride-modified polypropylene, maleic anhydride-modified polyethylene, maleic acid-modified polypropylene, itaconic acid-modified polypropylene, glycidyl acrylate-modified polypropylene, or glycidyl methacrylate-modified polypropylene, and more preferably maleic anhydride-modified polypropylene, maleic anhydride-modified polyethylene, maleic acid-modified polypropylene, glycidyl acrylate-modified polypropylene, or glycidyl methacrylate-modified polypropylene.

[0073] The hydroxyl group-modified polyolefin polymer is the same as the acid-modified polyolefin polymer except that "at least one of the unsaturated carboxylic acid and its derivatives" shown in the above (1) or (2) is changed to "an unsaturated alcohol or an unsaturated carboxylic acid ester having a hydroxyl group", that is, it has monomer units (modifying groups) derived from an unsaturated alcohol or an unsaturated carboxylic acid ester having a hydroxyl group.

[0074] Examples of the unsaturated alcohol include allyl alcohol, crotyl alcohol, methyl vinyl carbinol, allyl carbinol, methyl propipenyl carbinol, 4-penten-1-ol, 10-undecen-1-ol, propargyl alcohol, 1,4-pentadien-3-ol, 1,4-hexadien-3-ol, 3,5-hexadien-2-ol, 2,4-hexadien-1-ol, 3-butene-1,2-diol, 2,5-dimethyl-3-hexene-2,5-diol, 1,5-hexadien-3,4-diol, 2,6-octadiene-4,5-diol and the like. Among these, the unsaturated alcohol is preferably allyl alcohol or allyl carbinol.

[0075] Examples of the unsaturated carboxylic acid ester having a hydroxyl group include 2-hydroxyethyl methacrylate, 2-hydroxypropyl methacrylate, 4-hydroxybutyl acrylate and the like.

[0076] Examples of the hydroxyl group-modified polyolefin-based polymer include ethylene-allyl alcohol copolymer, ethylene-crotyl alcohol copolymer, ethylene-methyl vinyl carbinol copolymer, ethylene-allyl carbinol copolymer, ethylene-4-penten-1-ol copolymer, ethylene-10-undecene-1-ol copolymer, propylene-allyl alcohol copolymer, propylene-crotyl alcohol copolymer, propylene-methyl vinyl carbinol copolymer, propylene-allyl carbinol copolymer, propylene-4-penten-1-ol copolymer, propylene-10-undecene-1-ol copolymer, 2-hydroxyethyl methacrylate-modified polypropylene, 2-hydroxypropyl methacrylate-modified polypropylene, 4-hydroxybutyl acrylate-modified polypropylene, 2-hydroxyethyl methacrylate-modified polyethylene, 2-hydroxypropyl methacrylate-modified polyethylene, 4-hydroxybutyl acrylate-modified polyethylene, and the like. Among these, the hydroxyl group-modified polyolefin-based polymer is preferably a propylene-4-penten-1-ol copolymer, a propylene-10-undecene-1-ol copolymer, 2-hydroxyethyl methacrylate-modified polypropylene, or 4-hydroxybutyl acrylate-modified polypropylene, and more preferably 2-hydroxyethyl methacrylate-modified polypropylene or 4-hydroxybutyl acrylate-modified polypropylene.

[0077] The hydroxyl group-modified polyolefin-based polymer can also be produced by converting a functional group introduced using a chain transfer agent during polymerization or converting a functional group introduced into the terminal double bond of the polyolefin-based polymer, and it may be introduced with a hydroxyl group by any method.

[0078] The position of the hydroxyl group in the hydroxyl group-modified polyolefin-based polymer is not particularly limited, and it may be a polyolefin whose chain is modified with a hydroxyl group, a polyolefin modified with hydroxyl groups at both ends, or an olefin modified with a hydroxyl group at one end. Further, the position of the hydroxyl group may be any combination of the above.

[0079] The epoxy-modified polyolefin polymer is the same as the acid-modified polyolefin polymer except that "at least one of the unsaturated carboxylic acid and its derivatives" shown in the above (1) or (2) is changed to an "unsaturated epoxy compound", that is, it has a monomer unit (modified group) derived from the unsaturated epoxy compound.

[0080] Examples of the unsaturated epoxy compound include glycidyl acrylate, glycidyl methacrylate, glycidyl itaconate, allyl glycidyl ether, 2-methylallyl glycidyl ether, styrene-p-glycidyl ether, and the like. Among these, the unsaturated epoxy compound is preferably glycidyl acrylate or glycidyl methacrylate.

[0081] Examples of the epoxy-modified polyolefin polymer include ethylene-glycidyl (meth)acrylate copolymer, ethylene-glycidyl (meth)acrylate-methyl (meth)acrylate copolymer, ethylene-glycidyl (meth)acrylate-ethyl (meth)acrylate copolymer, ethylene-glycidyl (meth)acrylate-normal propyl (meth)acrylate copolymer, ethylene-glycidyl (meth)acrylate-isopropyl (meth)acrylate copolymer, ethylene-glycidyl (meth)acrylate-normal butyl (meth)acrylate copolymer, ethylene-glycidyl (meth)acrylate-isobutyl (meth)acrylate copolymer, ethylene-glycidyl (meth)acrylate-2-ethylhexyl (meth)acrylate copolymer, and ethylene-glycidyl (meth)acrylate-vinyl acetate copolymer, glycidyl (meth)acrylate-modified polyethylene, glycidyl (meth)acrylate-modified polypropylene, and the like. Among these, the epoxy-modified polyolefin polymer is preferably an ethylene-glycidyl (meth)acrylate copolymer, glycidyl (meth)acrylate-modified polyethylene, or glycidyl (meth)acrylate-modified polypropylene, and more preferably an ethylene-glycidyl (meth)acrylate copolymer or glycidyl (meth)acrylate-modified polypropylene.

[0082] In addition, as the epoxy-modified polyolefin polymer, those obtained by reacting a polyolefin having a group reactive with an epoxy group with an epoxy group-containing compound can be used. Specifically, methods such as melt-kneading both of them can be mentioned.

[0083] For the production of the epoxy-modified polyolefin polymer, various methods can be used, such as "Practical Polymer Alloy Design" (written by Fumio Ide, Kogyo Chosa Kai (1996)), Prog. Polym. Sci., 24, 81-142 (1999), etc. That is, any of the solution method, bulk method, and melt-kneading method may be used. Also, these methods may be used in combination.

[0084] A polyolefin having a group reactive with an epoxy group can be obtained by introducing a compound reactive with an epoxy group into the polyolefin.

[0085] Examples of the compound reactive with an epoxy group include compounds having a group with active hydrogen having reactivity with an epoxy group, and specifically, compounds having a group derived from carboxylic acid, amine, phenol, thiol, etc. Among these, the compound reactive with an epoxy group is preferably a compound having a group derived from carboxylic acid, and more preferably an unsaturated carboxylic acid or its derivative. The compound reactive with an epoxy group may be used alone or in combination of two or more.

[0086] Examples of the unsaturated carboxylic acid include unsaturated compounds having one or more carboxylic acid groups, unsaturated compounds having one or more anhydrous carboxylic acid groups, etc. Examples of the unsaturated group of the unsaturated carboxylic acid include vinyl group, vinylene group, unsaturated cyclic hydrocarbon group, etc. Examples of the unsaturated carboxylic acid include acrylic acid, methacrylic acid, maleic acid, fumaric acid, tetrahydrophthalic acid, itaconic acid, citraconic acid, crotonic acid, isocrotonic acid, norbornenedicarboxylic acid, bicyclo[2,2,1]hept-2-ene-5,6-dicarboxylic acid, etc. Examples of the derivative of the unsaturated carboxylic acid include unsaturated carboxylic acid anhydride, unsaturated carboxylic acid halide, unsaturated carboxylic acid amide, unsaturated carboxylic acid imide, unsaturated carboxylic acid ester, etc. Examples of the derivative of the unsaturated carboxylic acid include maleinyl chloride, maleinyl imide, maleic anhydride, itaconic anhydride, citraconic anhydride, tetrahydrophthalic anhydride, bicyclo[2,2,1]hept-2-ene-5,6-dicarboxylic anhydride, dimethyl maleate, monomethyl maleate, diethyl maleate, diethyl fumarate, dimethyl itaconate, diethyl citraconate, dimethyl tetrahydrophthalate, dimethyl bicyclo[2,2,1]hept-2-ene-5,6-dicarboxylate, hydroxyethyl (meth)acrylate, hydroxypropyl (meth)acrylate, aminoethyl methacrylate, aminopropyl methacrylate, etc.

[0087] Among these, the unsaturated carboxylic acid or its derivative is preferably maleic anhydride, (meth)acrylic acid, itaconic anhydride, citraconic anhydride, tetrahydrophthalic anhydride, bicyclo[2,2,1]hept-2-ene-5,6-dicarboxylic anhydride, hydroxyethyl (meth)acrylate, or aminopropyl methacrylate, and more preferably maleic anhydride, itaconic anhydride, citraconic anhydride, tetrahydrophthalic anhydride, or bicyclo[2,2,1]hept-2-ene-5,6-dicarboxylic anhydride. That is, the compound that reacts with the epoxy group is particularly preferably maleic anhydride.

[0088] As a method for introducing a compound that reacts with an epoxy group into a polyolefin, various methods can be adopted. For example, a method of subjecting a compound that reacts with an epoxy group to a graft reaction or a terminal reaction on the polyolefin main chain, a method of radical copolymerizing an olefin such as ethylene or propylene with a compound that reacts with an epoxy group, etc. can be exemplified.

[0089] The epoxy group-containing compound is preferably a polyepoxide having a repeating unit represented by the following general formula (i).

[0090] [Chemical formula] (In formula (i), R E1 represents a divalent organic group, R E2 and R E3 each independently represent a monovalent organic group, and the asymmetric carbon shows an arbitrary configuration on the condition that it does not oppose the epoxy structure.)

[0091] A monoepoxide may be added to the epoxy group-containing compound, and it is also possible to use a single or a mixture of plural epoxy group-containing compounds.

[0092] It is also possible to directly use commercially available epoxy group-containing compounds. Examples of commercially available epoxy group-containing compounds include TEPIC-S, TEPIC-L, TEPIC-HP, etc. manufactured by Nissan Chemical Industries, Ltd.

[0093] Examples of the epoxy-modified polyolefin obtained by reacting a polyolefin having a group reactive with an epoxy group with an epoxy group-containing compound include the reaction product of maleic anhydride-modified polyethylene and TEPIC-S, and the reaction product of maleic anhydride-modified polypropylene and TEPIC-S. Preferably, it is the reaction product of maleic anhydride-modified polypropylene and TEPIC-S.

[0094] The carbodiimide-modified polyolefin-based polymer is obtained by reacting a polyolefin having a group reactive with a carbodiimide group with a carbodiimide group-containing compound. Specifically, it can be obtained by a method such as melt-kneading the two.

[0095] For the production of the carbodiimide-modified polyolefin-based polymer, various methods can be used, such as "Practical Polymer Alloy Design" (written by Fumio Ide, Industrial Research Institute (1996)), Prog. Polym. Sci., 24, 81-142 (1999), etc. That is, any of the solution method, the bulk method, and the melt-kneading method may be used. Also, these methods may be used in combination.

[0096] A polyolefin having a group reactive with a carbodiimide group can be obtained by introducing a compound reactive with a carbodiimide group into the polyolefin.

[0097] Examples of the compound that reacts with the carbodiimide group include, for example, a compound having a group having active hydrogen with reactivity with the carbodiimide group, specifically, a compound having a group derived from a carboxylic acid, an amine, an alcohol, a thiol, etc. Among these, the compound that reacts with the carbodiimide group is preferably a compound having a group derived from a carboxylic acid, and more preferably an unsaturated carboxylic acid or a derivative thereof. Further, as the compound that reacts with the carbodiimide group, in addition to the compound having a group having active hydrogen, a compound having a group that can be easily converted into a group having active hydrogen by water or the like can also be preferably used. Specifically, a compound having an epoxy group or a glycidyl group can be mentioned. The compound that reacts with the carbodiimide group may be used alone or in combination of two or more kinds.

[0098] Examples of the unsaturated carboxylic acid include unsaturated compounds having one or more carboxylic acid groups, unsaturated compounds having one or more carboxylic anhydride groups, and the like. Examples of the unsaturated group of the unsaturated carboxylic acid include a vinyl group, a vinylene group, an unsaturated cyclic hydrocarbon group, and the like. Examples of the unsaturated carboxylic acid include acrylic acid, methacrylic acid, maleic acid, fumaric acid, tetrahydrophthalic acid, itaconic acid, citraconic acid, crotonic acid, isocrotonic acid, norbornenedicarboxylic acid, bicyclo[2,2,1]hept-2-ene-5,6-dicarboxylic acid, and the like. Examples of the derivative of the unsaturated carboxylic acid include unsaturated carboxylic anhydrides, unsaturated carboxylic acid halides, unsaturated carboxylic acid amides, unsaturated carboxylic acid imides, unsaturated carboxylic acid esters, and the like. Examples of the derivative of the unsaturated carboxylic acid include maleenyl chloride, maleenyl imide, maleic anhydride, itaconic anhydride, citraconic anhydride, tetrahydrophthalic anhydride, bicyclo[2,2,1]hept-2-ene-5,6-dicarboxylic anhydride, dimethyl maleate, monomethyl maleate, diethyl maleate, diethyl fumarate, dimethyl itaconate, diethyl citraconate, dimethyl tetrahydrophthalate, dimethyl bicyclo[2,2,1]hept-2-ene-5,6-dicarboxylate, hydroxyethyl (meth)acrylate, hydroxypropyl (meth)acrylate, glycidyl (meth)acrylate, aminoethyl methacrylate, aminopropyl methacrylate, and the like.

[0099] Among these, the unsaturated carboxylic acid or its derivative is preferably maleic anhydride, (meth)acrylic acid, itaconic anhydride, citraconic anhydride, tetrahydrophthalic anhydride, bicyclo[2,2,1]hept-2-ene-5,6-dicarboxylic anhydride, hydroxyethyl (meth)acrylate, glycidyl methacrylate, or aminopropyl methacrylate, and more preferably maleic anhydride, itaconic anhydride, citraconic anhydride, tetrahydrophthalic anhydride, bicyclo[2,2,1]hept-2-ene-5,6-dicarboxylic anhydride. That is, as the compound that reacts with the carbodiimide group, maleic anhydride is particularly preferred.

[0100] As a method for introducing a compound that reacts with a carbodiimide group into a polyolefin, various methods can be adopted. For example, a method of graft-reacting or end-reacting a compound that reacts with a carbodiimide group onto the polyolefin main chain, a method of radical copolymerizing an olefin such as propylene with a compound that reacts with a carbodiimide group, and the like can be mentioned.

[0101] The carbodiimide group-containing compound is preferably a polycarbodiimide having a repeating unit represented by the following general formula (ii). -N=C=N-R1- ···(ii) (In the formula (ii), R1 represents a divalent organic group.)

[0102] The method for synthesizing polycarbodiimide is not particularly limited. For example, polycarbodiimide can be synthesized by reacting an organic polyisocyanate in the presence of a catalyst that promotes the carbodiimidization reaction of the isocyanate group.

[0103] A monocarboxydiimide may be added to the polycarbodiimide, and it is also possible to use it alone or in combination of two or more carbodiimide group-containing compounds.

[0104] Incidentally, as the carbodiimide group-containing compound, a commercially available carbodiimide group-containing compound can be used as it is. Examples of the commercially available carbodiimide group-containing compounds include Carbodilite (registered trademark) HMV-15CA, Carbodilite (registered trademark) HMV-8CA, Carbodilite (registered trademark) LA1 manufactured by Nisshinbo Industries, Inc., Stabaxol (registered trademark) P, Stabaxol (registered trademark) P400 manufactured by Rhein Chemie, and the like.

[0105] Examples of the carbodiimide-modified polyolefin polymer include reaction products of maleic anhydride-modified polyethylene and carbodiite HMV-15CA, reaction products of maleic anhydride-modified polyethylene and carbodiite HMV-8CA, reaction products of maleic anhydride-modified polyethylene and carbodiite LA1, reaction products of maleic anhydride-modified polyethylene and stabaxol P400, reaction products of maleic anhydride-modified polypropylene and carbodiite HMV-15CA, reaction products of maleic anhydride-modified polypropylene and carbodiite HMV-8CA, reaction products of maleic anhydride-modified polypropylene and carbodiite LA1, reaction products of maleic anhydride-modified polypropylene and stabaxol P400, and the like. Among these, the carbodiimide-modified polyolefin polymer is preferably a reaction product of maleic anhydride-modified polypropylene and carbodiite HMV-15CA, a reaction product of maleic anhydride-modified polypropylene and carbodiite HMV-8CA, or a reaction product of maleic anhydride-modified polypropylene and carbodiite LA1, and more preferably a reaction product of maleic anhydride-modified polypropylene and carbodiite HMV-15CA.

[0106] From the viewpoint of mechanical strengths such as impact strength, fatigue characteristics, and rigidity, the modified group content of the modified polyolefin resin (B) is preferably 0.01% by mass or more and 10% by mass or less, more preferably 0.1% by mass or more and 6% by mass or less, and still more preferably 1% by mass or more and 5% by mass or less. When the modified polyolefin resin (B) contains a modified polyolefin polymer obtained by a graft reaction or a terminal reaction, the modified group content of the modified polyolefin resin (B) is preferably 0.01% by mass or more and 10% by mass or less. When the modified polyolefin resin (B) contains a modified polyolefin polymer obtained by copolymerization, the modified group content of the modified olefin resin (B) preferably contains 0.01% by mass or more and 10% by mass or less.

[0107] The intrinsic viscosity ([η]) of the modified polyolefin polymer is preferably 0.1 dl / g or more and 3.0 dl / g or less, more preferably 0.1 dl / g or more and 1.0 dl / g or less.

[0108] In this specification, the intrinsic viscosity (unit: dl / g) is a value measured at a temperature of 135 °C using tetralin as a solvent by the following method.

[0109] Using an Ubbelohde viscometer, the reduced viscosity is measured at three points of concentrations of 0.1 g / dl, 0.2 g / dl, and 0.5 g / dl. The reduced viscosity is plotted against the concentration, and the intrinsic viscosity is determined by the extrapolation method of extrapolating the concentration to zero. The calculation method of the intrinsic viscosity by the extrapolation method is described, for example, on page 491 of "Polymer Solutions, Polymer Experimental Chemistry 11" (published by Kyoritsu Shuppan Co., Ltd. in 1982).

[0110] As a method for producing the modified polyolefin polymer, for example, the methods exemplified in "Practical Polymer Alloy Design" (written by Fumio Ide, Industrial Research Institute (1996)), Prog. Polym. Sci., 24, 81-142 (1999), Japanese Patent Laid-Open No. 2002-308947, etc. can be used. Further, as a method for producing the modified polyolefin polymer, for example, any of the methods such as the solution method, the bulk method, and the melt kneading method may be used. Further, as a method for producing the modified polyolefin polymer, these methods may be combined.

[0111] As the modified polyolefin polymer, commercially available products may be used. Examples of commercially available modified polyolefin polymers include Umemex (registered trademark) manufactured by Sanyo Chemical Industries, Ltd., Toyotac (registered trademark) manufactured by Toyobo Co., Ltd., Toughmer M (registered trademark) manufactured by Mitsui Chemicals, Inc., Admer (registered trademark) manufactured by Mitsui Chemicals, Inc., Modic (registered trademark) manufactured by Mitsubishi Chemical Corporation, Arrowbase (registered trademark) manufactured by Unitika Ltd., Sumifit (registered trademark) manufactured by Sumitomo Chemical Co., Ltd., Bondfast (registered trademark) manufactured by Sumitomo Chemical Co., Ltd., etc.

[0112] The content of the modified polyolefin resin (B) is 1% by mass or more and 20% by mass or less, preferably 1% by mass or more and 15% by mass or less, and more preferably 5% by mass or more and 15% by mass or less, based on the total content of (A), (B), (C), (D), and (E) being 100% by mass, from the viewpoint of obtaining a molded article with relatively excellent tensile strength while containing the plant-derived filler. When the modified polyolefin resin (B) contains two or more modified polypropylene polymers, the content of the modified polyolefin resin (B) is the total content thereof.

[0113] [Plant-derived filler (C)] The plant-derived filler (C) may be a component that contains at least a part of plant-derived components and can be dispersed in the polyolefin resin (A). As the plant-derived filler (C), various known plant-derived fillers can be used. Examples of the plant-derived filler (C) include cellulose, wood powder, bamboo powder, rice, rice bran, starch, etc. Among these, the plant-derived filler (C) is preferably cellulose, wood powder, or bamboo powder, and more preferably cellulose or wood powder. The polyolefin resin composition may contain only one kind of the plant-derived filler (C) or two or more kinds.

[0114] Examples of cellulose include powdered cellulose, cellulose fiber, lignocellulose fiber, wood fiber, etc. Examples of the raw materials of cellulose include natural materials such as wood (coniferous tree, broad-leaved tree), cotton linter, kenaf, manila hemp (abaca), sisal hemp, jute, savannah grass, esparto grass, bagasse, rice straw, wheat straw, reed, bamboo, etc. Also, cellulose may be modified with functional monomers containing, for example, acids, amines, epoxies, etc. Among these, cellulose is preferably cellulose fiber, lignocellulose fiber, or wood fiber.

[0115] The wood powder is mainly the finely crushed wood powder. Examples of the wood include hinoki, cedar, pine, beech, fir, oak, maple, elm, tamarack, oaks, beech, kaki, cherry, photinia, camellia, cypress, oak, chestnut, hornbeam, zelkova, Japanese walnut, birch, alder, rubber tree, ramie, lawan, telentang, mango, brick tree, lanshin bock, chatchin mock, nurude, urushi, hazeno ki, harigiri, hannoki, kabanoki, asada, kixasage, tabebuia, ibe, gayakan, corokia, canary wood, canarium, Katsura, Terminalia, idigbo, aphara, erima, meranti, parashipis, chengal, resak, apiton, kruin, yan, chutel, dona, kapul, yakar, melanch, upna, kaki no ki, koktan, butabuta, kuri, bintangor, santa maria, carofilum, geronggan, garcinia, manil, ishnoki, walnut, nogurumi, nan, queensland walnut, bilian, tabunoki, greenheart acacia, kokrojua, african teak, afzelia, nemunoki, acre, albizia, false acacia, magnolia, honoki, kaya, kuwa, eucalyptus, platanus, nanakamado, poplar, mokkok, keyaki, nire, teak, mafoganii, ginkgo, spruce, larch, ichii, kaya, etc.

[0116] The size of the plant-derived filler (C) is preferably 5000 μm or less, more preferably 3000 μm or less, still more preferably 1000 μm or less, and particularly preferably 200 μm or less.

[0117] When the plant-derived filler (C) is wood fiber, the width of the wood fiber is preferably 1 μm or more and 100 μm or less, more preferably 10 μm or more and 50 μm or less. Also, the length of the wood fiber is preferably 0.1 mm or more and 50 mm or less, more preferably 1 mm or more and 5 mm or less.

[0118] The plant-derived filler (C) can be obtained, for example, by treating at least one raw material selected from the group consisting of woods, pulps, papers, plant stems or leaves, and plant husks using a pulverizer.

[0119] Among the plant-derived filler (C), the cellulose fiber can be obtained, for example, by the following method. The above-mentioned cellulose raw material is roughly pulverized using a cutting machine such as a shredder as necessary. Next, the roughly pulverized cellulose raw material is processed or dried using an impact crusher or an extruder. Then, the processed cellulose raw material is stirred using a medium-type crusher to obtain cellulose fibers.

[0120] The cellulose fiber is preferably a biomass nanofiber. In the present specification, the biomass nanofiber means either a long fiber biomass nanofiber or a short fiber biomass nanofiber.

[0121] Examples of the biomass nanofiber include cellulose nanofiber, chitin nanofiber, chitosan nanofiber, silk nanofiber, etc. Among these, the biomass nanofiber is preferably cellulose nanofiber (CNF) from the viewpoints of chemical stability, thermal stability, and cost.

[0122] From the viewpoint of the aspect ratio, the average fiber diameter of the biomass nanofiber is preferably 3 nm or more and 100 nm or less, and more preferably 10 nm or more and 50 nm or less. The average fiber diameter can be calculated from the average value of the fiber diameters (n is about 20) measured based on an electron micrograph taken at an appropriate magnification.

[0123] Examples of the biomass nanofiber include mechanically defibrated biomass nanofibers produced by mechanical defibration, chemically modified biomass nanofibers produced through chemical modification, etc. Among these, the biomass nanofiber is preferably a mechanically defibrated biomass nanofiber.

[0124] As the biomass nanofiber, a commercially available product may be used. Examples of commercially available biomass nanofibers include BiNFi-s (registered trademark) manufactured by Sugino Machine Limited, Celencia (registered trademark) manufactured by Nippon Paper Industries Co., Ltd., ELLEX (registered trademark) manufactured by Oji Paper Co., Ltd., nanoforest (registered trademark) manufactured by Chugoku Pulp & Paper Co., Ltd., and the like.

[0125] From the viewpoint of obtaining a molded article having relatively excellent tensile strength while containing the plant-derived filler (C), the content of the plant-derived filler (C) is 1% by mass or more and 80% by mass or less, preferably 5% by mass or more and 60% by mass or less, and more preferably 5% by mass or more and 20% by mass or less, with the total content of (A), (B), (C), (D), and (E) being 100% by mass. When the polyolefin-based resin composition contains two or more plant-derived fillers (C), the content of the plant-derived filler (C) is the total content thereof.

[0126] [Hydrophilic resin (D) having a hydroxyl group] Examples of the hydrophilic resin (D) having a hydroxyl group include polyvinyl alcohol, polyethylene oxide, polyethylene glycol, polyglycerin, and the like. Among these, from the viewpoint of obtaining a molded article having relatively excellent tensile strength, the hydrophilic resin (D) having a hydroxyl group is preferably polyvinyl alcohol, polyethylene oxide, or polyethylene glycol, and more preferably polyvinyl alcohol. The polyolefin-based resin composition may contain only one kind of the hydrophilic resin (D) having a hydroxyl group or may contain two or more kinds thereof. In one aspect, the polyolefin-based resin composition according to the present embodiment is such that the hydrophilic resin (D) having a hydroxyl group is polyvinyl alcohol.

[0127] Polyvinyl alcohol is a water-soluble polymer obtained as a hydrolyzate (saponified product) of vinyl acetate. Examples of polyvinyl alcohol include various polyvinyl alcohols such as low-saponified products, partially saponified products, and fully saponified products. Also, examples of polyvinyl alcohol include polyvinyl alcohol having functional groups such as carboxylic acid, sulfonic acid, quaternary ammonium salt, polyethylene oxide group, and acetoacetyl group; and various polyvinyl alcohols such as copolymer polyvinyl alcohol of ethylene, butene, butanediol, etc.

[0128] From the viewpoint of obtaining a molded article that contains a plant-derived filler and has relatively excellent tensile strength, the saponification degree of polyvinyl alcohol is preferably 10 or more and 100 or less, more preferably 50 or more and 100 or less, and even more preferably 60 or more and 80 or less. In one aspect, the polyolefin-based resin composition according to this embodiment is such that the hydrophilic resin (D) having the hydroxyl group is polyvinyl alcohol having a saponification degree of 10 or more and 100 or less.

[0129] From the viewpoint of obtaining a molded article that contains a plant-derived filler, is dispersed in the polyolefin-based material, and has relatively excellent tensile strength, the degree of polymerization of polyvinyl alcohol is preferably 100 or more and 1000 or less, more preferably 100 or more and 600 or less. In one aspect, the polyolefin-based resin composition according to this embodiment is such that the hydrophilic resin (D) having the hydroxyl group is polyvinyl alcohol having a degree of polymerization of 100 or more and 1000 or less.

[0130] Commercially available products may be used as the polyvinyl alcohol. Examples of commercially available polyvinyl alcohol include Denka Poval manufactured by Denka Co., Ltd., Kuraray Poval manufactured by Kuraray Co., Ltd., JMR manufactured by Nippon Vinylon K.K., and Poval manufactured by Nippon Vinylon K.K.

[0131] The content of the hydrophilic resin (D) having a hydroxyl group is 1% by mass or more and 30% by mass or less, preferably 5% by mass or more and 30% by mass or less, more preferably 5% by mass or more and 25% by mass or less, from the viewpoint of obtaining a molded article having relatively excellent tensile strength while containing a plant-derived filler, with the total content of (A), (B), (C), (D) and (E) being 100% by mass. When the polyolefin resin composition contains a hydrophilic resin (D) having two or more hydroxyl groups, the content of the hydrophilic resin (D) having a hydroxyl group is the total content thereof.

[0132] [Compound (E) for crosslinking hydroxyl groups] The compound (E) for crosslinking hydroxyl groups may be a crosslinking agent that crosslinks the hydroxyl groups contained in the hydrophilic resin (D) having a hydroxyl group and the hydroxyl groups contained in the plant-derived filler (C). The crosslinking agent is preferably a compound that binds and crosslinks two or more hydroxyl groups. As the crosslinking agent, known compounds that chemically react with hydroxyl groups to crosslink (chemical crosslinking) or physically interact with hydroxyl groups to crosslink (physical crosslinking) can be used.

[0133] Examples of the crosslinking between hydroxyl groups include coordination bonds (preferably chelate bonds) with metal ions and ionic bonds with metal ions.

[0134] Examples of the functional groups contained in the crosslinking agent include carboxyl group, isocyanate group, aldehyde group, hydroxyl group, phenolic hydroxyl group, epoxy group, amino group, N-methylol group, vinyl group and the like.

[0135] Examples of such crosslinking agents include metal compounds, polyvalent carboxylic acid compounds, polyvalent isocyanate compounds, aminoaldehyde compounds, glyoxal compounds, polyvalent epoxy compounds, carbodiimide, melamine compounds, amino compounds, vinyl compounds, and the like. Among these, the crosslinking agent is preferably at least one selected from the group consisting of zirconium compounds, titanium compounds, carbodiimide, boron compounds, polyvalent carboxylic acid compounds, polyvalent isocyanate compounds, aminoaldehyde compounds, glyoxal compounds, and polyvalent epoxy compounds, and more preferably at least one selected from the group consisting of zirconium compounds, titanium compounds, carbodiimide, boron compounds, polyvalent isocyanate compounds, and polyvalent carboxylic acid compounds. As one aspect, in the polyolefin resin composition according to the present embodiment, the compound (E) that crosslinks the hydroxyl group is at least one selected from the group consisting of zirconium compounds, titanium compounds, carbodiimide, boron compounds, polyvalent isocyanate compounds, and polyvalent carboxylic acid compounds.

[0136] Examples of the metal compound include boron compounds, titanium compounds, zirconium compounds, aluminum compounds, and the like.

[0137] Examples of the boron compound include at least one of boric acid or its salts represented by boric acid such as boric acid, potassium borate, and sodium borate (borax) (hereinafter also referred to as boric acid (salt)).

[0138] Examples of the titanium compound include titanium, titanium acetylacetate, triethanolamine titanate, ammonium lactate titanate, lactate titanate, salts of inorganic acids, organic titanium alkoxides [Ti(OR)4], organic titanium acylates [Ti(OCOR) n (OR) 4-n , organic titanium chelate compounds, organic titanium polymers or organic titanium oligomers [partial hydrolysis condensates of organic titanium alkoxides or organic titanium acylates: -(Ti(OR) n O)m Examples include "-". As specific examples, organic titanium acrylates include, for example, polyhydroxy titanium stearate and the like. Further, as organic titanium chelate compounds, for example, titanium lactate (e.g., Organicx TC-310 manufactured by Matsumoto Fine Chemical Co., Ltd.), titanium triethanolamine (e.g., Organicx TC-400 manufactured by Matsumoto Fine Chemical Co., Ltd.) and the like can be mentioned. Further, as salts of inorganic acids, for example, titanium tetrachloride and the like can be mentioned.

[0139] Examples of zirconium compounds include zirconium, zirconium fluoride, zirconium chloride, zirconium bromide, zirconium sulfate, zirconium nitrate, zirconium carbonate, ammonium zirconium carbonate, potassium zirconium carbonate, zirconium acetate, zirconium stearate, zirconium octylate, zirconium citrate, zirconium lactate, zirconium phosphate, zirconium oxalate, zirconic acid, zirconate, ammonium zirconium carbonate, zirconium tetraacetylacetonate (e.g., Organicx ZC-150 manufactured by Matsumoto Fine Chemical Co., Ltd.), zirconium monoacetylacetonate (e.g., Organicx ZC-540 manufactured by Matsumoto Fine Chemical Co., Ltd.), zirconium bisacetylacetonate, zirconium monoethylacetoacetate, zirconium acetate and the like.

[0140] Examples of aluminum compounds include inorganic acid salts such as aluminum sulfate, aluminum lactate, aluminum chloride, basic polyaluminum chloride, aluminum nitrate and the like.

[0141] Examples of metal compounds other than the compounds mentioned above include zinc sulfate, satin white and the like.

[0142] In addition to the compounds mentioned above, various metal alkoxides can also be used as the metal compound. When a metal alkoxide is used as the crosslinking agent, the crosslinking between the hydroxyl groups contained in the hydrophilic resin (D) having hydroxyl groups and the hydroxyl groups contained in the plant-derived filler (C) is generally carried out by a method called the sol-gel method.

[0143] Specifically, first, when the metal alkoxide is hydrolyzed, metal hydroxide and alcohol are generated. Next, dehydration condensation occurs between the metal hydroxide, the hydroxyl groups contained in the hydrophilic resin (D) having hydroxyl groups, and the hydroxyl groups contained in the plant-derived filler (C), whereby the hydroxyl groups contained in the hydrophilic resin (D) having hydroxyl groups and the hydroxyl groups contained in the plant-derived filler (C) are crosslinked.

[0144] For example, when tetraethoxysilane is used as the metal alkoxide, first, when tetraethoxysilane is hydrolyzed, orthosilicic acid and ethanol are generated. Next, dehydration condensation occurs between the orthosilicic acid, the hydroxyl groups contained in polyvinyl alcohol as the hydrophilic resin (D) having hydroxyl groups, and the hydroxyl groups contained in cellulose nanofibers as the plant-derived filler (C), whereby the hydroxyl groups contained in polyvinyl alcohol and the hydroxyl groups contained in cellulose nanofibers are crosslinked via silicon.

[0145] The metal alkoxide contains, for example, two or more alkoxy groups such as methoxy group, ethoxy group, and propoxy group.

[0146] Examples of the metal element contained in the metal alkoxide include barium, calcium, magnesium, aluminum, boron, gallium, indium, lanthanum, silicon, zirconium, titanium, tin, etc. Among these, the metal element is preferably silicon, zirconium, titanium, or aluminum.

[0147] Examples of the metal alkoxide include metal alkoxides containing divalent metal elements such as dimethoxy barium, diethoxy barium, dipropoxy barium, dimethoxy calcium, diethoxy calcium, dipropoxy calcium, dimethoxy magnesium, diethoxy magnesium, dipropoxy magnesium, etc.; metal alkoxides containing trivalent metal elements such as trimethoxy aluminum, triethoxy aluminum, tripropoxy aluminum, triisopropoxy aluminum, trimethoxy boron, triethoxy boron, tripropoxy boron, triisopropoxy boron, trimethoxy gallium, triethoxy gallium, tripropoxy gallium, triisopropoxy gallium, trimethoxy indium, triethoxy indium, tripropoxy indium, triisopropoxy indium, trimethoxy lanthanum, triethoxy lanthanum, tripropoxy lanthanum, triisopropoxy lanthanum, etc.; and metal alkoxides containing tetravalent metal elements such as tetramethoxy silane, tetraethoxy silane, tetrapropoxy silane, tetraisopropoxy silane, tetrabutoxy silane, tetramethoxy zirconium, tetraethoxy zirconium, tetrapropoxy zirconium, tetraisopropoxy zirconium, tetrabutoxy zirconium, tetramethoxy titanium, tetraethoxy titanium, tetrapropoxy titanium, tetraisopropoxy titanium, tetrabutoxy titanium, etc.

[0148] The metal alkoxide may also be represented by the following formula (1). R1 n M(OR2) m-n ···(1) (In formula (1), R1 and R2 represent alkyl groups, M represents a metal element, m represents the valence of the metal element M, and n represents an integer satisfying 0 ≦ n ≦ m - 1. Note that R1 and R2 may be the same or different from each other.)

[0149] Examples of such metal alkoxides include methyltrimethoxysilane, methyltriethoxysilane, methyltripropoxysilane, ethyltrimethoxysilane, ethyltriethoxysilane, ethyltripropoxysilane, propoxytriethoxysilane, propoxytripropoxysilane, etc.

[0150] Examples of polycarboxylic acid compounds include malic acid, citric acid, glutaric acid, adipic acid, etc.

[0151] Examples of polyisocyanate compounds include aromatic diisocyanates such as phenylenediisocyanate (PDI), tolylene diisocyanate (TDI), naphthalene diisocyanate (NDI), 4,4'-diisocyanate diphenylmethane (MDI); aromatic aliphatic diisocyanates such as xylylene diisocyanate (XDI); aliphatic or alicyclic diisocyanates such as hydrogenated TDI, hydrogenated XDI, hydrogenated MDI, hexamethylene diisocyanate (HMDI), isophorone diisocyanate (IPDI) and polyol adducts which are derivatives thereof; burette bodies; polyisocyanates with three or more functional groups which are trimers; trifunctional isocyanates such as lysine triisocyanate (LTI); various oligomers or polymers containing isocyanate, etc.

[0152] The polyisocyanate compound may be a urethane compound or a polyurethane compound.

[0153] Examples of aminoaldehyde compounds include urea-formaldehyde resin, melamine formaldehyde resin, polyamide-polyurea resin, polyamide-epichlorohydrin, etc.

[0154] Examples of glyoxal compounds include glyoxal, urea-glyoxal resin, dialdehyde starch, etc.

[0155] Examples of the polyvalent epoxy compounds include ethylene glycol diglycidyl ether, epichlorohydrin, triglycidyl isocyanurate, polyamide-epoxy resin, and the like.

[0156] Examples of the carbodiimide include monocarbodimide, polycarbodiimide, and the like.

[0157] Examples of the monocarbodimide include dicyclohexylcarbodiimide, diisopropylcarbodiimide, dimethylcarbodiimide, diisobutylcarbodiimide, dioctylcarbodiimide, t-butylisopropylcarbodiimide, dodecylisopropylcarbodiimide, diphenylcarbodiimide, di-o-tolylcarbodiimide, di-p-tolylcarbodiimide, cyanamide, di-t-butylcarbodiimide, 1,3-bis(trimethylsilyl)carbodiimide, di-β-naphthylcarbodiimide, benzylisopropylcarbodiimide, and the like.

[0158] As the polycarbodiimide, for example, commercially available products such as Carbodilite manufactured by Nisshinbo Chemical Inc. can be used.

[0159] Further, as the polycarbodiimide, for example, those produced by known production methods described in JP-A-59-187029 and the like may be used. Examples of such production methods include a method of obtaining a polycarbodiimide compound by heating a monoisocyanate compound, a diisocyanate compound, and a triisocyanate compound in a non-reactive organic solvent in the presence of a catalyst such as 3-methyl-1-phenyl-2-phosphorate oxide and decarboxylating to convert an isocyanate group into a carbodiimide group.

[0160] Examples of the amine compound include ethylenediamine, hexamethylenediamine, diethylenetriamine, dipropylenetriamine, triethylenetetramine, tetraethylenepentamine, N-aminoethylpiperazine, 1,4-bis(3-aminopropyl)piperazine, trimethylhexamethylenediamine, polyoxypropylenediamine, and the like.

[0161] Examples of the melamine compound include trimethylol melamine, melamine resin, and the like.

[0162] Examples of the vinyl compound include bisvinylsulfonylmethyl ether and the like.

[0163] From the viewpoint of obtaining a molded article having relatively excellent tensile strength while containing a plant-derived filler, the content of the compound (E) that crosslinks the hydroxyl group is 0.1% by mass or more and 10% by mass or less, preferably 0.1% by mass or more and 5% by mass or less, and more preferably 0.2% by mass or more and 3% by mass or less, with the total content of (A), (B), (C), (D), and (E) being 100% by mass. When the compound (E) that crosslinks the hydroxyl group is a combination of two or more, the content of the compound (E) that crosslinks the hydroxyl group is the total content.

[0164] [Other Additives] The polyolefin resin composition according to this embodiment may contain other additives as necessary. Examples of other additives include pigments, dyes, inorganic fillers, neutralizing agents, antioxidants, lubricants, copper poisoning inhibitors, antifogging agents, antistatic agents, processing stabilizers, ultraviolet absorbers, light stabilizers, nucleating agents, clarifying nucleating agents, processing aids, metal soaps, foaming agents, antibacterial agents, plasticizers, flame retardants, flame retardant aids, crosslinking agents for polyolefins, crosslinking aids for polyolefins, brightening agents, fluidity modifiers, crystallization retardants, and the like.

[0165] The manufacturing method of the polyolefin resin composition according to this embodiment is not particularly limited. For example, it can be manufactured by melt-kneading each component. Examples of the kneader used for melt-kneading include a single-screw extruder, a twin-screw extruder, a Banbury mixer, a hot roll, and the like.

[0166] The temperature of the melt-kneading is preferably 160°C or higher and 230°C or lower, and the time of the melt-kneading is preferably 1 minute or longer and 15 minutes or shorter. Also, the melt-kneading of each component may be performed simultaneously or sequentially.

[0167] 2. Molded article The molded article according to this embodiment contains the above-mentioned polyolefin resin composition. The molded article is a molded article formed by a conventionally known method. Examples of such molded articles include injection molded articles, press molded articles, vacuum molded articles, vacuum press molded articles, pressure air molded articles, foam molded articles, extrusion molded articles, and the like. Examples of the molding method of such molded articles include an injection molding method, a press molding method, a vacuum molding method, a vacuum press molding method, a pressure air molding method, a foam molding method, an extrusion molding method, and the like.

[0168] The molded article according to this embodiment is preferably an injection molded article. Examples of the injection molding method for molding an injection molded article include a general injection molding method, an injection foam molding method, a supercritical injection foam molding method, a super high-speed injection molding method, an injection compression molding method, an injection press molding method, a gas assist injection molding method, a sandwich molding method, a sandwich foam molding method, an insert / outset molding method, and the like.

[0169] Examples of the uses of the molded article according to this embodiment include automotive interior and exterior members, home appliance parts, building materials, miscellaneous goods, furniture, food containers, beverage containers, medical containers, containers, and the like. Among these, the use of the molded article is preferably an automotive interior and exterior member or a home appliance part.

[0170] In one aspect, the molded article according to this embodiment may be obtained by the methods described in the following Step 1 and Step 2. Step 1: Crushing a molded article containing the above polyolefin resin composition to obtain crushed products Step 2: Molding the crushed products to obtain a molded article containing the above polyolefin resin composition

[0171] The present invention includes the following aspects. [1] A polyolefin resin composition comprising a polyolefin resin (A), a modified polyolefin resin (B), a plant-derived filler (C), a hydrophilic resin (D) having a hydroxyl group, and a compound (E) that crosslinks the hydroxyl group, with the total content of (A), (B), (C), (D) and (E) being 100% by mass, the content of the polyolefin resin (A) being 1% by mass or more and 96.4% by mass or less, the content of the modified polyolefin resin (B) being 1% by mass or more and 20% by mass or less, the content of the plant-derived filler (C) being 1% by mass or more and 80% by mass or less, the content of the hydrophilic resin (D) having a hydroxyl group being 1% by mass or more and 30% by mass or less, and the content of the compound (E) that crosslinks the hydroxyl group being 0.1% by mass or more and 10% by mass or less. [2] The polyolefin resin composition according to [1], wherein the polyolefin resin (A) is a polypropylene resin. [3] The polyolefin resin composition according to [1] or [2], wherein the modified polyolefin resin (B) contains at least one selected from the group consisting of an acid-modified polyolefin polymer, a hydroxyl group-modified polyolefin polymer, an epoxy-modified polyolefin polymer, and a carbodiimide-modified polyolefin polymer. [4] The polyolefin resin composition according to any one of [1] to [3], wherein the hydrophilic resin (D) having a hydroxyl group is polyvinyl alcohol. [5] The polyolefin resin composition according to any one of [1] to [3], wherein the hydrophilic resin (D) having a hydroxyl group is polyvinyl alcohol having a saponification degree of 10 or more and 100 or less. [6] The polyolefin resin composition according to any one of [1] to [3], wherein the hydrophilic resin (D) having a hydroxyl group is polyvinyl alcohol having a degree of polymerization of 100 or more and 1000 or less. [7] The polyolefin resin composition according to any one of [1] to [6], wherein the compound (E) that crosslinks the hydroxyl group is at least one selected from the group consisting of a zirconium compound, a titanium compound, a carbodiimide, a boron compound, a polyvalent isocyanate compound, and a polyvalent carboxylic acid compound. [8] A molded article comprising the polyolefin resin composition according to any one of [1] to [7]. [9] The molded article according to [8], which is an injection molded article.

Examples

[0172] Hereinafter, the present invention will be described more specifically using examples and comparative examples, but the present invention is not limited to the following examples. Also, the operations described below were carried out under conditions of normal temperature and normal pressure unless otherwise specified.

[0173] [Measurement methods for physical properties] (Melt flow rate) It was measured by Method A in accordance with JIS K7210-1:2014 and K7210-2:2014 under the conditions of a temperature of 230 ° C and a load of 2.16 kg.

[0174] (Limiting viscosity number) Using an Ubbelohde viscometer, the reduced viscosity was measured for a plurality of concentrations, the reduced viscosity was plotted against the concentration, and the limiting viscosity number was determined by the "extrapolation method" of extrapolating the concentration to zero. More specifically, the method described on page 491 of "Polymer Solutions, Polymer Experimentation 11" (published by Kyoritsu Shuppan Co., Ltd. in 1982) was used. The reduced viscosity was measured at three points of concentrations of 0.1 g / dl, 0.2 g / dl, and 0.5 g / dl, plotted against the concentration, and determined by the method of extrapolating the concentration to zero.

[0175] [Components used in examples and comparative examples] The components used in the examples and comparative examples are shown below.

[0176] (1) Polyolefin resin (A) Polypropylene homopolymer (hPP-1, Noblen HR100EG; manufactured by Sumitomo Chemical Co., Ltd.)

[0177] The physical properties of hPP-1 were as follows. · Melt flow rate (temperature 230 °C, load 2.16 kg): 23 - 25 g / 10 min · Melting point: 164 °C

[0178] (2) Modified polyolefin resin (B) Maleic anhydride-modified polypropylene (MAH-1, Umemex 1010; manufactured by Sanyo Chemical Industries, Ltd.)

[0179] The physical properties of MAH-1 were as follows. · Content of maleic anhydride monomer units contained in MAH-1: 3.5 mass% · Intrinsic viscosity: 0.3 dl / g

[0180] (3) Plant-derived filler (C) Cellulose nanofiber (CNF-1, 2 mass% aqueous dispersion, BiNFi-s IMa-10002; manufactured by Sugino Machine Limited)

[0181] (4) Hydrophilic resin (D) having a hydroxyl group · Polyvinyl alcohol 1 (PVA-1, degree of polymerization 500, saponification degree 100, K-05; manufactured by Denka Co., Ltd.) · Polyvinyl alcohol 2 (PVA-2, degree of polymerization 500, saponification degree 72, L-10; manufactured by Kuraray Co., Ltd.) · Polyvinyl alcohol 3 (PVA-3, degree of polymerization 100, saponification degree 65, JMR-3M; manufactured by Nippon Vinylon K.K.)

[0182] Regarding the degree of polymerization and saponification degree of the above PVA-1 to PVA-3, the information disclosed by the manufacturer was referred to.

[0183] (5) Compound (E) that crosslinks the hydroxyl group · Crosslinking agent 1 (aqueous zirconium chloride compound solution, solid content 30% by mass, ZC-126; manufactured by Matsumoto Fine Chemical Co., Ltd.) · Crosslinking agent 2 (titanium lactate: Ti(OH)2[OCH(CH3)COOH]2 compound aqueous solution, solid content 44% by mass, TC-310; manufactured by Matsumoto Fine Chemical Co., Ltd.)

[0184] (6) Other additives · Antioxidant 1 (Irganox 1010; manufactured by BASF Japan Ltd.) · Antioxidant 2 (Irgafos 168; manufactured by BASF Japan Ltd.)

[0185] <Preparation of an aqueous solution of a hydrophilic resin having a hydroxyl group> (Preparation Example 1: Preparation of PVA-1 aqueous solution) To 450% by mass of ion-exchanged water, 50% by mass of PVA-1 was added little by little while stirring at room temperature to obtain a mixed solution. The obtained mixed solution was heated to 90 °C and stirred for 3 hours to completely dissolve PVA-1. The obtained solution was allowed to cool to room temperature to obtain a PVA-1 aqueous solution.

[0186] (Preparation Example 2: Preparation of PVA-2 aqueous solution) To 400% by mass of ion-exchanged water, 100% by mass of PVA-2 was added little by little while stirring at room temperature to obtain a mixed solution. The obtained mixed solution was stirred at room temperature for 3 hours to completely dissolve PVA-2, thereby obtaining a PVA-2 aqueous solution.

[0187] (Preparation Example 3: Preparation of PVA-3 aqueous solution) To 450% by mass of ion-exchanged water, 50% by mass of PVA-3 was added little by little while stirring at room temperature to obtain a mixed solution. The obtained mixed solution was stirred at room temperature for 3 hours to completely dissolve PVA-3, thereby obtaining a PVA-3 aqueous solution.

[0188] <Production of a plant-derived filler and hydrophilic resin composite> (Production Example 1: Production of CNF-PVA Composite F-1) 100% by mass (in terms of solid content) of CNF-1, 200% by mass (in terms of solid content) of an aqueous solution of PVA-2, and 1.0% by mass (in terms of solid content) of Crosslinking Agent 1 were mixed to obtain a mixed dispersion. The obtained mixed dispersion was freeze-dried to obtain CNF-PVA composite F-1. The crushed product obtained by crushing CNF-PVA composite F-1 using a crusher was used in the following examples.

[0189] (Production Example 2: Production of CNF-PVA Composite F-2) 100% by mass (in terms of solid content) of CNF-1, 200% by mass (in terms of solid content) of an aqueous solution of PVA-3, and Crosslinking Agent 1; 1.0% by mass (in terms of solid content) were mixed to obtain a mixed dispersion. The obtained mixed dispersion was freeze-dried to obtain CNF-PVA composite F-1. The crushed product obtained by crushing CNF-PVA composite F-2 using a crusher was used in the following examples.

[0190] (Production Example 3: Production of CNF-PVA Composite F-3) CNF-PVA composite F-3 was obtained in the same manner as in Production Example 1, except that 65% by mass (in terms of solid content) of CNF-2 and 0.33% by mass (in terms of solid content) of Crosslinking Agent 1 were used.

[0191] (Production Example 4: Production of CNF-PVA Composite F-4) 100% by mass (in terms of solid content) of CNF-1, 200% by mass (in terms of solid content) of an aqueous solution of PVA-1, and 0.51% by mass (in terms of solid content) of Crosslinking Agent 1 were mixed to obtain a mixed dispersion. The obtained mixed dispersion was freeze-dried to obtain CNF-PVA composite F-4. The crushed product obtained by crushing CNF-PVA composite F-4 using a crusher was used in the following examples.

[0192] (Production Example 5: Production of CNF-PVA Composite F-5) Except for using 1.5% by mass (in terms of solid content) of crosslinking agent 2 instead of crosslinking agent 1, CNF-PVA composite F-5 was obtained in the same manner as in Production Example 4.

[0193] (Production Example 6: Production of CNF-PVA composite F-6) 100% by mass (in terms of solid content) of CNF-1 and 200% by mass (in terms of solid content) of an aqueous solution of PVA-1 were mixed to obtain a mixed dispersion. The obtained mixed dispersion was freeze-dried to obtain CNF-PVA composite F-6. The crushed product obtained by crushing CNF-PVA composite F-6 using a crusher was used in the following examples.

[0194] (Production Example 7: Production of CNF-PVA composite F-7) Except for using 1.0% by mass (in terms of solid content) of crosslinking agent 1, CNF-PVA composite F-7 was obtained in the same manner as in Production Example 4.

[0195] The formulations of CNF-PVA composites F-1 to F-7 are shown in Table 1.

[0196]

Table 1

[0197] (Example 1) 10.2% by mass of MAH-1 and 31.8% by mass of the crushed product of CNF-PVA composite F-1 were uniformly mixed in a powder state to obtain a mixture. With respect to 100% by mass of the obtained mixture, 0.2% by mass of antioxidant 1 and 0.2% by mass of antioxidant 2 were added to the mixture and uniformly mixed in a powder state to obtain a mixture. The obtained mixture was fed into a desktop small twin-screw kneader (Xplore; manufactured by DSM) and kneaded under the conditions of a resin temperature of 180°C, a kneading time of 10 minutes, and a screw rotation speed of 200 rpm to obtain resin composition G-1-1.

[0198] Next, 42% by mass of the resin composition G-1-1 obtained above and 58% by mass of hPP-1 were uniformly mixed to obtain a mixture. The obtained mixture was supplied to a tabletop twin-screw kneader (the same as above) and kneaded under the conditions of a resin temperature of 180°C, a kneading time of 10 minutes, and a screw rotation speed of 200 rpm to obtain a polyolefin resin composition G-1-2.

[0199] The obtained polyolefin resin composition G-1-2 was preheated at 190°C for 5 minutes, and a pressure of 5 MPa was applied for 5 minutes to obtain a press-molded article with a thickness of 300 μm. A test piece for physical property evaluation was obtained by punching out a test piece from the obtained press-molded article using a JIS K 7113-2 (JIS No. 7) dumbbell.

[0200] (Example 2) A polyolefin resin composition G-2-2 was obtained in the same manner as in Example 1, except that 31.8% by mass of the crushed CNF-PVA composite F-2 was used.

[0201] The obtained polyolefin resin composition G-2-2 was preheated at 190°C for 5 minutes, and a pressure of 5 MPa was applied for 5 minutes to obtain a press-molded article with a thickness of 300 μm. A test piece for physical property evaluation was obtained by punching out a test piece from the obtained press-molded article using a JIS K 7113-2 (JIS No. 5) dumbbell.

[0202] (Example 3) A polyolefin resin composition and a test piece for physical property evaluation were obtained in the same manner as in Example 2, except that 17.0% by mass of the crushed CNF-PVA composite F-3, 10.1% by mass of MAH-1, and 73.0% by mass of hPP-1 were used.

[0203] (Example 4) A polyolefin resin composition and a test piece for physical property evaluation were obtained in the same manner as in Example 2, except that 30.9% by mass of the crushed CNF-PVA composite F-4, 10.1% by mass of MAH-1, and 59.0% by mass of hPP-1 were used.

[0204] (Example 5) A polyolefin resin composition and a test piece for physical property evaluation were obtained in the same manner as in Example 2, except that 32.1% by mass of the crushed CNF-PVA composite F-5 and 57.7% by mass of hPP-1 were used.

[0205] (Example 6) 10.2% by mass of MAH-1 and 31.8% by mass of the crushed CNF-PVA composite F-1 were uniformly mixed in a powder state to obtain a mixture. To 100% by mass of the obtained mixture, 0.2% by mass of antioxidant 1 and 0.2% by mass of antioxidant 2 were added to the mixture and uniformly mixed in a powder state to obtain a mixture. The obtained mixture was fed into a twin-screw extruder (KZW12TW manufactured by Technovel Corporation, L / D = 75), melt-kneaded under the conditions of a cylinder temperature of 180 °C and a screw rotation speed of 300 rpm, and pelletized to obtain a resin composition G-6-1.

[0206] Next, 42% by mass of the obtained resin composition G-6-1 and 58% by mass of hPP-1 were uniformly mixed to obtain a mixture. The obtained mixture was fed into a twin-screw extruder (the same as above), melt-kneaded under the conditions of a cylinder temperature of 180 °C and a screw rotation speed of 300 rpm, and pelletized to obtain a polyolefin resin composition G-6-2.

[0207] The polyolefin resin composition G-6-2 obtained above was injection-molded using an SI-30III type injection molding machine (manufactured by Toyo Machine Metal Co., Ltd.) under the conditions of a molding temperature of 200 °C and a mold temperature of 50 °C to obtain a test piece for physical property evaluation; a scaled test piece (type A12, thickness 2 mm) conforming to JIS K 7139.

[0208] (Example 7) A polyolefin resin composition and a test piece for physical property evaluation were obtained in the same manner as in Example 1, except that 31.8% by mass of the crushed CNF-PVA composite F-7 was used.

[0209] (Comparative Example 1) A polyolefin resin composition and a test piece for physical property evaluation were obtained in the same manner as in Example 1, except that 10.0% by mass of MAH-1, 30.0% by mass of the crushed product of CNF-PVA composite F-6, and 60.0% by mass of hPP-1 were used.

[0210] [Evaluation] <Tensile Strength Test (Unit: MPa)> For the test pieces for physical property evaluation obtained in Examples 1 to 7 and Comparative Example 1, a tensile strength test was conducted under the following conditions according to the method specified in JIS K7113. · Examples 1 to 5 and Comparative Example 1 Measurement temperature: 23°C, Tensile speed: 200 mm / min · Examples 6 to 7 Measurement temperature: 23°C, Tensile speed: 50 mm / min

[0211] The formulations of the polyolefin resin compositions obtained in Examples 1 to 7 and Comparative Example 1 and the evaluation results of the molded bodies are shown in Table 2.

[0212]

Table 2

[0213] From Table 2, it was found that the molded body that satisfies all the constituent requirements of the present invention is relatively excellent in tensile strength while containing a plant-derived filler.

Claims

1. comprising a polyolefin resin (A), a modified polyolefin resin (B), a plant-derived filler (C), a hydrophilic resin (D) having a hydroxyl group, and a compound (E) that crosslinks the hydroxyl group, with the total content of (A), (B), (C), (D) and (E) being 100% by mass, the content of the polyolefin resin (A) being 1% by mass or more and 96.4% by mass or less, the content of the modified polyolefin resin (B) being 1% by mass or more and 20% by mass or less, the content of the plant-derived filler (C) being 1% by mass or more and 80% by mass or less, the content of the hydrophilic resin (D) having a hydroxyl group being 1% by mass or more and 30% by mass or less, and the content of the compound (E) that crosslinks the hydroxyl group being 0.1% by mass or more and 10% by mass or less, a polyolefin resin composition.

2. The polyolefin resin composition according to claim 1, wherein the polyolefin resin (A) is a polypropylene resin.

3. The polyolefin resin composition according to claim 1, wherein the modified polyolefin resin (B) contains at least one selected from the group consisting of an acid-modified polyolefin polymer, a hydroxyl group-modified polyolefin polymer, an epoxy-modified polyolefin polymer, and a carbodiimide-modified polyolefin polymer.

4. The polyolefin resin composition according to claim 1, wherein the hydrophilic resin (D) having a hydroxyl group is polyvinyl alcohol.

5. The polyolefin resin composition according to claim 1, wherein the hydrophilic resin (D) having a hydroxyl group is polyvinyl alcohol having a saponification degree of 10 or more and 100 or less.

6. The polyolefin resin composition according to claim 1, wherein the hydrophilic resin (D) having a hydroxyl group is polyvinyl alcohol having a polymerization degree of 100 or more and 1000 or less.

7. The polyolefin resin composition according to claim 1, wherein the compound (E) that crosslinks the hydroxyl group is at least one selected from the group consisting of a zirconium compound, a titanium compound, a carbodiimide, a boron compound, a polyvalent isocyanate compound, and a polyvalent carboxylic acid compound.

8. A molded article comprising the polyolefin resin composition according to any one of claims 1 to 7.

9. The molded article according to claim 8, which is an injection molded article.

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