Polypropylene resin composition

Abstract

To provide a polypropylene resin composition which contains a plant-derived filler, while retaining mechanical strength and exhibiting comparatively excellent flowability.SOLUTION: A polypropylene resin composition according to the present invention includes a polypropylene resin (A), a modified polypropylene resin (B), an organomodified siloxane compound (C), and a plant-derived filler (D). Defining the total content of (A), (B), (C), and (D) as 100 mass%, the content of the polypropylene resin (A) is 5 mass% or more and 79.8 mass% or less, the content of the modified polypropylene resin (B) is 0.1 mass% or more and 10 mass% or less, the content of the organomodified siloxane compound (C) is 0.1 mass% or more and 15 mass% or less, and the content of the plant-derived filler (D) is 20 mass% or more and 70 mass% or less.SELECTED DRAWING: None

Description

Technical Field

[0001] The present invention relates to a polypropylene-based resin composition.

Background Art

[0002] Molded articles containing polypropylene-based resin compositions are used in industrial parts such as household goods, automotive parts, and electrical parts, as well as in daily necessities and miscellaneous goods. Fillers are compounded in such resin compositions to enhance mechanical strength and the like. Examples of such fillers include inorganic powders such as talc and silica; cellulose-based 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, resin compositions containing plant-derived fillers such as cellulose-based powders of wood powder and bamboo powder have attracted attention. As such resin compositions, for example, Patent Document 1 discloses a cellulose composite resin containing polypropylene, maleic anhydride-modified polypropylene, and cellulose fibers.

Prior Art Documents

Patent Documents

[0004]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0005] However, polypropylene-based resin compositions containing plant-derived fillers such as cellulose-based powders have a problem of low fluidity and poor processability.

[0006] The present invention has been made in view of such problems, and an object thereof is to provide a polypropylene-based resin composition that maintains mechanical strength while containing a plant-derived filler and has relatively excellent fluidity.

Means for Solving the Problems

[0007] The polypropylene-based resin composition according to the present invention contains a polypropylene-based resin (A), a modified polypropylene-based resin (B), an organically modified siloxane compound (C), and a plant-derived filler (D). Assuming that the total content of (A), (B), (C), and (D) is 100% by mass, the content of the polypropylene-based resin (A) is 5% by mass or more and 79.8% by mass or less, the content of the modified polypropylene-based resin (B) is 0.1% by mass or more and 10% by mass or less, the content of the organically modified siloxane compound (C) is 0.1% by mass or more and 15% by mass or less, the content of the plant-derived filler (D) is 20% by mass or more and 70% by mass or less.

Advantages of the Invention

[0008] According to the present invention, it is possible to provide a polypropylene-based resin composition that contains a plant-derived filler, maintains mechanical strength, and has relatively excellent fluidity.

Modes for Carrying Out the Invention

[0009] Hereinafter, embodiments of the present invention will be described, but the present invention is not limited to the following embodiments.

[0010] The polypropylene-based resin composition according to the present embodiment contains a polypropylene-based resin (A), a modified polypropylene-based resin (B), an organically modified siloxane compound (C), and a plant-derived filler (D).

[0011] [Polypropylene-based Resin (A)] The polypropylene-based resin (A) is a resin containing a propylene-based polymer. In this specification, the polypropylene-based resin (A) refers to an unmodified polypropylene-based resin.

[0012] The propylene-based polymer is a polymer containing more than 50% by mass of monomer units derived from propylene. Examples of the propylene-based polymer include a propylene homopolymer, a random copolymer of propylene and a monomer other than propylene, and a heterophasic propylene polymerization material. The polypropylene-based resin (A) may contain only one type of propylene-based polymer or may contain two or more types.

[0013] From the viewpoint of improving heat resistance, the polypropylene-based resin (A) preferably contains one or more selected from the group consisting of a propylene homopolymer, a random copolymer of propylene and a monomer other than propylene, and a heterophasic propylene polymerization material, and more preferably contains one or more selected from the group consisting of a propylene homopolymer and a heterophasic propylene polymerization material.

[0014] The propylene homopolymer can be produced, for example, by performing a polymerization step of polymerizing propylene using a polymerization catalyst.

[0015] 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 (compounds of Group 4 transition metals of the periodic table having a cyclopentadienyl ring, compounds that form ionic complexes, organoaluminum compounds, etc.) are supported on inorganic particles (silica, clay minerals, etc.).

[0016] Examples of the polymerization catalyst include 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.

[0017] In addition, a polymer obtained by prepolymerizing propylene in the presence of the polymerization catalyst can also be used as the polymerization catalyst.

[0018] 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.

[0019] 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 vessels are connected in series.

[0020] From the viewpoint of being excellent industrially and economically, the polymerization method is preferably a continuous gas-phase polymerization method or a bulk-gas phase polymerization method in which the bulk polymerization method and the gas-phase polymerization method are carried out continuously.

[0021] 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.

[0022] 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 below 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.

[0023] The random copolymer of propylene and a monomer other than propylene contains monomer units derived from propylene and monomer units derived from a monomer other than propylene. In the said random copolymer, the content of the monomer units 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.

[0024] 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.

[0025] 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.

[0026] Examples of the random copolymer of propylene and a monomer other than propylene include propylene-ethylene random copolymer, propylene-1-butene random copolymer, propylene-1-hexene random copolymer, propylene-1-octene random copolymer, propylene-ethylene-1-butene random copolymer, propylene-ethylene-1-hexene random copolymer, propylene-ethylene-1-octene random copolymer, etc.

[0027] A 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.

[0028] 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.

[0029] 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.

[0030] In the heterophasic propylene polymerization material, the total of polymer I and polymer II contained in the heterophasic propylene polymerization material may be 100% by mass based on 100% by mass of the total mass of the heterophasic propylene polymerization material.

[0031] Polymer I may contain 70% by mass or more of monomer units derived from propylene (provided that the total mass of polymer I is 100% by mass). Polymer I may be, for example, a propylene homopolymer or may contain monomer units derived from a monomer other than propylene. When polymer I contains monomer units derived from a monomer 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 polymer I.

[0032] 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.

[0033] 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.

[0034] Examples of polymer I containing monomer units derived from monomers other than propylene include propylene-ethylene copolymer, propylene-1-butene copolymer, propylene-1-hexene copolymer, propylene-1-octene copolymer, propylene-ethylene-1-butene copolymer, propylene-ethylene-1-hexene copolymer, propylene-ethylene-1-octene copolymer, and the like.

[0035] Polymer I is preferably a propylene homopolymer, a propylene-ethylene copolymer, a propylene-1-butene copolymer, or a propylene-1-hexene copolymer, and more preferably a propylene homopolymer.

[0036] 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, and 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.

[0037] 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.

[0038] 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).

[0039] 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).

[0040] In 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 even more preferably at least one selected from the group consisting of ethylene and 1-butene.

[0041] Examples of the polymer II include a propylene-ethylene copolymer, a propylene-ethylene-1-butene copolymer, a propylene-ethylene-1-hexene copolymer, a propylene-ethylene-1-octene copolymer, a propylene-ethylene-1-decene copolymer, a propylene-1-butene copolymer, a propylene-1-hexene copolymer, a propylene-1-octene copolymer, a 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.

[0042] 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 polymer material.

[0043] 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.

[0044] 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.

[0045] 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.

[0046] From the viewpoint of improving the moldability 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.

[0047] 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.

[0048] The content of the polypropylene resin (A) is 5% by mass or more and 79.8% by mass or less, preferably 25% by mass or more and 79.4% by mass or less, and more preferably 42% by mass or more and 78.9% by mass or less, based on the total content of (A), (B), (C) and (D) being 100% by mass, from the viewpoint of improving fluidity. When the polypropylene resin (A) contains two or more kinds of propylene polymers, the content of the polypropylene resin (A) is the total content thereof.

[0049] [Modified polypropylene resin (B)] The modified polypropylene resin (B) is a resin containing a modified polypropylene polymer.

[0050] Examples of the modified polypropylene polymer include acid-modified polypropylene polymers, hydroxyl-modified polypropylene polymers, epoxy-modified polypropylene polymers, carbodiimide-modified polypropylene polymers, oxazoline-modified polypropylene polymers, and the like. Among these, from the viewpoint of improving fluidity, the modified polypropylene polymer is preferably one or more selected from the group consisting of acid-modified polypropylene polymers, hydroxyl-modified polypropylene polymers, epoxy-modified polypropylene polymers, carbodiimide-modified polypropylene polymers, and oxazoline-modified polypropylene polymers, and more preferably an acid-modified polypropylene polymer. The modified polypropylene resin (B) may contain only one kind of modified polypropylene polymer or two or more kinds. The polypropylene resin composition according to the present embodiment, as one aspect, the modified polypropylene resin (B) includes one or more selected from the group consisting of acid-modified polypropylene polymers, hydroxyl-modified polypropylene polymers, epoxy-modified polypropylene polymers, carbodiimide-modified polypropylene polymers, and oxazoline-modified polypropylene polymers.

[0051] The acid-modified polypropylene-based polymer is as 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 derivatives. (1) A homopolymer of propylene, a random copolymer of at least two types of propylene, or a heterophasic propylene polymerization material obtained by copolymerizing at least two types of propylene after homopolymerizing propylene, to which at least one of an unsaturated carboxylic acid and its derivatives is subjected to a graft reaction or a terminal reaction. (2) A copolymer of at least one type of propylene and at least one of an unsaturated carboxylic acid and its derivatives.

[0052] Note that the propylene in the above (1) and (2) may be the same as or different from the propylene constituting the polypropylene-based polymer in the polypropylene-based resin (A).

[0053] 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, maleic monoamide, maleic diamide, fumaric monoamide, 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 as the unsaturated carboxylic acid, those generated by dehydrating citric acid, malic acid, etc. in the step of grafting to polypropylene may also be used. At least one of the unsaturated carboxylic acid and its derivatives is preferably maleic anhydride, glycidyl acrylate, or glycidyl methacrylate.

[0054] The acid-modified polypropylene-based polymer, in one aspect, is as shown in the following (1’) or (2’). (1’) A propylene-based polymer containing 70% by mass or more, preferably 80% by mass or more of monomer units derived from propylene, to which maleic anhydride is subjected to a graft reaction or a terminal reaction. (2’) A copolymer of propylene and glycidyl methacrylate or maleic anhydride.

[0055] Examples of the acid-modified polypropylene-based polymer include maleic anhydride-modified polypropylene, 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 polypropylene-based polymer is preferably maleic anhydride-modified polypropylene, maleic acid-modified polypropylene, itaconic acid-modified polypropylene, glycidyl acrylate-modified polypropylene, glycidyl methacrylate-modified polypropylene, and more preferably maleic anhydride-modified polypropylene, maleic acid-modified polypropylene, glycidyl acrylate-modified polypropylene, glycidyl methacrylate-modified polypropylene.

[0056] The hydroxyl group-modified polypropylene-based polymer is the same as the acid-modified polypropylene-based 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.

[0057] 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.

[0058] Examples of the unsaturated carboxylic acid ester having a hydroxyl group include 2-hydroxyethyl methacrylate, 2-hydroxypropyl methacrylate, 4-hydroxybutyl acrylate, and the like.

[0059] Examples of the hydroxyl group-modified polypropylene-based polymer include 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-undecen-1-ol copolymer, 2-hydroxyethyl methacrylate-modified polypropylene, 2-hydroxypropyl methacrylate-modified polypropylene, 4-hydroxybutyl acrylate-modified polypropylene, and the like. Among these, the hydroxyl group-modified polypropylene-based polymer is preferably propylene-4-penten-1-ol copolymer, propylene-10-undecen-1-ol copolymer, 2-hydroxyethyl methacrylate-modified polypropylene, 4-hydroxybutyl acrylate-modified polypropylene, and more preferably 2-hydroxyethyl methacrylate-modified polypropylene, 4-hydroxybutyl acrylate-modified polypropylene.

[0060] The hydroxyl group-modified polypropylene-based polymer can also be produced by converting a functional group introduced using a chain transfer agent during polymerization, or by converting a functional group introduced to the terminal double bond of the polypropylene-based polymer, etc. It may be introduced with a hydroxyl group by any method.

[0061] The position of the hydroxyl group in the hydroxyl group-modified polypropylene-based polymer is not particularly limited, and it may be a polypropylene modified with a hydroxyl group in the chain, modified with hydroxyl groups at both ends, or polypropylene modified with a hydroxyl group at one end. Also, the position of the hydroxyl group may be any combination of the above.

[0062] The epoxy group-modified polypropylene-based polymer is the same as the acid-modified polypropylene-based polymer except that "at least one of the unsaturated carboxylic acid and its derivative" 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.

[0063] Examples of the unsaturated epoxy compound include glycidyl acrylate, glycidyl methacrylate, glycidyl itaconate, allyl glycidyl ether, 2-methylallyl glycidyl ether, styrene-p-glycidyl ether, etc. Among these, the unsaturated epoxy compound is preferably glycidyl acrylate or glycidyl methacrylate.

[0064] Examples of the epoxy group-modified polypropylene-based polymer include glycidyl (meth)acrylate-modified polypropylene, etc. The epoxy group-modified polypropylene-based polymer is preferably glycidyl (meth)acrylate-modified polypropylene.

[0065] Also, as the epoxy group-modified polypropylene-based polymer, one obtained by reacting a polypropylene having a group reactive with an epoxy group with an epoxy group-containing compound can be used. Specifically, methods such as melt-kneading the two can be mentioned.

[0066] For the production of an epoxy-modified polypropylene-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.

[0067] Polypropylene having a group that reacts with an epoxy group can be obtained by introducing a compound that reacts with an epoxy group into polypropylene.

[0068] Examples of the compound that reacts with an epoxy group include compounds having a group with active hydrogen having reactivity with an epoxy group, specifically, compounds having a group derived from carboxylic acid, amine, phenol, thiol, etc. Among these, the compound that reacts with an epoxy group is preferably a compound having a group derived from carboxylic acid, more preferably an unsaturated carboxylic acid or its derivative. The compound that reacts with an epoxy group may be used alone or in combination of two or more.

[0069] 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, 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 anhydride, unsaturated carboxylic halide, unsaturated carboxylic amide, unsaturated carboxylic imide, unsaturated carboxylic 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, aminopropyl methacrylate, etc.

[0070] Among these, the unsaturated carboxylic acid or its derivative is preferably maleic anhydride, acrylic acid, methacrylic acid, itaconic anhydride, citraconic anhydride, tetrahydrophthalic anhydride, bicyclo[2,2,1]hept-2-ene-5,6-dicarboxylic anhydride, hydroxyethyl (meth)acrylate, aminopropyl methacrylate; more preferably dicarboxylic anhydrides such as maleic anhydride, itaconic anhydride, citraconic anhydride, tetrahydrophthalic anhydride, bicyclo[2,2,1]hept-2-ene-5,6-dicarboxylic anhydride; and particularly preferably maleic anhydride. That is, the compound that reacts with the epoxy group is particularly preferably maleic anhydride.

[0071] As a method for introducing a compound that reacts with an epoxy group into polypropylene, various methods can be adopted. For example, methods such as graft-reacting or end-reacting a compound that reacts with an epoxy group onto the polypropylene main chain, and radical copolymerizing propylene with a compound that reacts with an epoxy group can be exemplified.

[0072] The epoxy group-containing compound is preferably a polyepoxide having a repeating unit represented by the following general formula (i).

[0073] [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 epoxide structure.)

[0074] A monoepoxide may be added to the epoxy group-containing compound, and it is also possible to use a single or a mixture of a plurality of epoxy group-containing compounds.

[0075] It is also possible to use a commercially available epoxy group-containing compound as it is. Examples of commercially available epoxy group-containing compounds include TEPIC-S, TEPIC-L, TEPIC-HP, etc. manufactured by Nissan Chemical Industries, Ltd.

[0076] Examples of the epoxy-modified polypropylene obtained by reacting a polypropylene having a group that reacts with an epoxy group with an epoxy group-containing compound include the reaction product of maleic anhydride-modified polypropylene and TEPIC-S, and preferably, it is the reaction product of maleic anhydride-modified polypropylene and TEPIC-S.

[0077] The carbodiimide-modified polypropylene-based polymer can be obtained by reacting polypropylene having a group that reacts with a carbodiimide group with a carbodiimide group-containing compound. Specifically, it can be obtained by a method such as melt-kneading the two.

[0078] For the production of the carbodiimide-modified polypropylene-based polymer, various methods can be used, such as "Practical Polymer Alloy Design" (written by Fumio Ide, Industrial Research Society (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.

[0079] Polypropylene having a group that reacts with a carbodiimide group can be obtained by introducing a compound that reacts with a carbodiimide group into polypropylene.

[0080] Examples of the compound that reacts with a carbodiimide group include compounds having a group having active hydrogen with reactivity with a carbodiimide group. Specifically, they are compounds having a group derived from a carboxylic acid, an amine, an alcohol, a thiol, etc. Among these, the compound that reacts with a carbodiimide group is preferably a compound having a group derived from a carboxylic acid, and more preferably an unsaturated carboxylic acid or its derivative. Also, as the compound that reacts with a carbodiimide group, in addition to compounds having a group having active hydrogen, compounds 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, compounds having an epoxy group or a glycidyl group are included. The compound that reacts with a carbodiimide group may be used alone or in combination of two or more.

[0081] 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, 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 anhydride, unsaturated carboxylic halide, unsaturated carboxamide, unsaturated carboxylic imide, unsaturated carboxylic ester, etc. 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, etc.

[0082] Among these, the unsaturated carboxylic acid or its derivative is preferably maleic anhydride, acrylic acid, methacrylic acid, itaconic anhydride, citraconic anhydride, tetrahydrophthalic anhydride, bicyclo[2,2,1]hept-2-ene-5,6-dicarboxylic anhydride, hydroxyethyl (meth)acrylate, glycidyl methacrylate, aminopropyl methacrylate, more preferably dicarboxylic anhydrides such as maleic anhydride, itaconic anhydride, citraconic anhydride, tetrahydrophthalic anhydride, bicyclo[2,2,1]hept-2-ene-5,6-dicarboxylic anhydride, and particularly preferably maleic anhydride. That is, as the compound that reacts with the carbodiimide group, maleic anhydride is particularly preferred.

[0083] As a method for introducing a compound that reacts with a carbodiimide group into polypropylene, various methods can be adopted. For example, a method of graft-reacting or end-reacting a compound that reacts with a carbodiimide group on the polypropylene main chain, a method of radical copolymerizing propylene and a compound that reacts with a carbodiimide group, etc. can be exemplified.

[0084] 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.)

[0085] The synthesis method of 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.

[0086] 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.

[0087] It is also possible to directly use commercially available carbodiimide group-containing compounds. Examples of commercially available carbodiimide group-containing compounds include Carbodilite (registered trademark) HMV-15CA, Carbodilite (registered trademark) HMV-8CA, and Carbodilite (registered trademark) LA1 manufactured by Nisshinbo Industries, Inc.; and Stabaxol (registered trademark) P and Stabaxol (registered trademark) P400 manufactured by Rhein Chemie.

[0088] Examples of the carbodiimide-modified polypropylene-based polymer include the reaction product of maleic anhydride-modified polypropylene and Carbodilite HMV-15CA, the reaction product of maleic anhydride-modified polypropylene and Carbodilite HMV-8CA, the reaction product of maleic anhydride-modified polypropylene and Carbodilite LA1, and the reaction product of maleic anhydride-modified polypropylene and Stabaxol P400. Among these, the carbodiimide-modified polypropylene-based polymer is preferably the reaction product of maleic anhydride-modified polypropylene and Carbodilite HMV-15CA, the reaction product of maleic anhydride-modified polypropylene and Carbodilite HMV-8CA, or the reaction product of maleic anhydride-modified polypropylene and Carbodilite LA1, and more preferably the reaction product of maleic anhydride-modified polypropylene and Carbodilite HMV-15CA.

[0089] From the perspective of mechanical strengths such as impact strength, fatigue characteristics, and rigidity, the content of the modifying group in the modified polypropylene-based resin (B) is preferably 0.01% by mass or more and 3.4% by mass or less, and more preferably 0.05% by mass or more and 1.0% by mass or less. When the modified polypropylene-based resin (B) contains a modified polypropylene-based polymer obtained by graft polymerization, the content of the modifying group in the modified polypropylene-based resin (B) is preferably 0.01% by mass or more and 3.4% by mass or less. When the modified polypropylene-based resin (B) contains a modified polypropylene-based polymer obtained by copolymerization, the content of the modifying group in the modified polypropylene-based resin (B) is preferably 0.01% by mass or more and 3.4% by mass or less.

[0090] The intrinsic viscosity of the modified polypropylene-based resin (B) is preferably 0.4 dl / g or more and 3.0 dl / g or less, more preferably 0.5 dl / g or more and 1.0 dl / g or less.

[0091] 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.

[0092] Using an Ubbelohde viscometer, the reduced viscosity is measured at three points with 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 Experimentation 11" (published by Kyoritsu Shuppan Co., Ltd. in 1982).

[0093] From the viewpoint of improving fluidity, the content of the modified polypropylene-based resin (B) 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, more preferably 0.1% by mass or more and 3% by mass or less, with the total content of (A), (B), (C), and (D) being 100% by mass. When the modified polypropylene-based resin (B) contains two or more modified polypropylene-based polymers, the content of the modified polypropylene-based resin (B) is the total content thereof.

[0094] [Organic-modified siloxane compound (C)] The organic-modified siloxane compound (C) is a polysiloxane containing an organic group. Examples of the organic group include an alkyl group, an aryl group, an alkoxy group, an amino group, an epoxy group, etc.

[0095] In addition, a compound in which a polysiloxane and a thermoplastic resin are chemically bonded is also an example of the organically modified siloxane compound (C). Examples of the thermoplastic resin include polyamides (nylon 6, nylon 66, etc.), polyolefins (polyethylene, polypropylene, etc.), polyesters (polyethylene terephthalate, polybutylene terephthalate, etc.), polycarbonate, polyamideimide, polyphenylene sulfide, polyphenylene oxide, polysulfone, polyethersulfone, polyetheretherketone, polyetherimide, styrene resins (polystyrene, ABS resin, etc.), liquid crystal polyester, copolymers of acrylonitrile and styrene, copolymers of nylon 6 and nylon 66, mixtures thereof, and the like. The thermoplastic resin is preferably a polyamide or a polyolefin, and more preferably a polyolefin.

[0096] The organically modified siloxane compound (C) preferably contains an alkyl group, and more preferably contains an alkyl group having 2 or more carbon atoms. That is, the organically modified siloxane compound (C) is preferably an alkyl-modified siloxane compound.

[0097] The weight average molecular weight of the organically modified siloxane compound (C) is preferably less than 90,000, more preferably 1,000 or more and less than 90,000, still more preferably 1,000 or more and 60,000 or less, and particularly preferably 1,000 or more and 50,000 or less.

[0098] The weight average molecular weight is determined by the GPC method. Approximately 5 mg of the organically modified siloxane compound (C) or the cold xylene-soluble portion of the masterbatch containing the organically modified siloxane compound (C) and polypropylene was dissolved in 5 mL of tetrahydrofuran to a concentration of about 1 mg / mL.

[0099] It was allowed to stand at room temperature for 2 hours and filtered. The filter used during filtration was a syringe filter with a diameter of 0.45 μm and made of PTFE.

[0100] Two Plus Pore series Poly Pore 7.5 mm I.D.×300 mm (manufactured by Agilent Technologies) GPC columns were connected in series and used. The mobile phase was tetrahydrofuran, and the flow rate was 1 mL / min. The temperature of the column oven was set at 35 °C. A differential refractive index detector was used as the detector. The RID cell temperature was 35 °C, and the injection volume of the sample solution was 100 μL. The calibration standard substance for the GPC column was PStQuick Kit-H (manufactured by Tosoh Corporation), and the polystyrene equivalent molecular weight was calculated.

[0101] (Equipment) In this measurement, an apparatus composed of the following equipment was used. (i) Liquid delivery pump: LC-20AD (manufactured by Shimadzu Corporation) (ii) Degasser: DG-2080-53 (manufactured by JASCO Corporation) (iii) Autosampler: SIL-20A HT (manufactured by Shimadzu Corporation) (iv) Column oven: CTO-20A (manufactured by Shimadzu Corporation) (v) Differential refractive index detector (RID): RID-10A (manufactured by Shimadzu Corporation) (vi) System controller: CBM-20A (manufactured by Shimadzu Corporation)

[0102] The polypropylene-based resin composition according to this embodiment may contain only one kind of the organically modified siloxane compound (C), or may contain two or more kinds.

[0103] As a raw material of the polypropylene-based resin composition according to this embodiment, a masterbatch containing the organically modified siloxane compound (C) and a thermoplastic resin may be used. Examples of the thermoplastic resin in the masterbatch of the organically modified siloxane compound (C) include the thermoplastic resins exemplified as the thermoplastic resins that can chemically bond with polysiloxane.

[0104] As the organically modified siloxane compound (C), commercially available products may be used. Examples of the masterbatch of the organically modified siloxane compound (C) include "TEGOMER (registered trademark) Antiscratch100" manufactured by Evonik Industries AG (a masterbatch containing an organically modified siloxane compound (C) and polypropylene. Content of the organically modified siloxane compound (C) in the masterbatch: approximately 50% by mass).

[0105] When using a masterbatch containing an organically modified siloxane compound (C) and polypropylene as the organically modified siloxane compound (C), the weight average molecular weight in the cold xylene soluble part of the masterbatch can be taken as the organically modified siloxane compound (C).

[0106] The cold xylene soluble part can be obtained by the following method. First, 5 g of a masterbatch containing an organically modified siloxane compound (C) and polypropylene is refluxed with boiling in a container for 30 minutes using 1000 mL of xylene until completely dissolved, and then this container is left standing in a constant temperature water bath set at 20°C for 20 hours to precipitate the cold xylene insoluble part. Next, the standing solution is filtered, and xylene is evaporated and removed from the filtrate and dried, whereby the cold xylene soluble part can be obtained.

[0107] From the viewpoint of improving fluidity, the content of the organically modified siloxane compound (C) is 0.1% by mass or more and 15% by mass or less, preferably 0.5% by mass or more and 10% by mass or less, more preferably 1% by mass or more and 5% by mass or less, with the total content of the above (A), (B), (C) and (D) being 100% by mass. When the polypropylene-based resin composition contains two or more kinds of organically modified siloxane compounds (C), the content of the organically modified siloxane compound (C) is the total content thereof.

[0108] [Plant-derived filler (D)] The plant-derived filler (D) may be any component that contains at least a part of plant-derived components and can be dispersed in the polypropylene-based resin (A). As the plant-derived filler (D), various known plant-derived fillers can be used. Examples of the plant-derived filler (D) include cellulose, wood powder, wood fiber, bamboo powder, etc. The plant-derived filler (D) is preferably cellulose, wood powder, wood fiber or bamboo powder, and more preferably cellulose. Note that the polyolefin-based resin composition may contain only one kind of the plant-derived filler (D) or may contain two or more kinds.

[0109] Examples of cellulose include powdered cellulose, cellulose fiber, lignocellulose 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, sabi grass, esparto grass, bagasse, rice straw, wheat straw, reed, bamboo, etc. Also, cellulose may be, for example, modified with a functional monomer containing an acid, an amine, an epoxy, etc. Among these, cellulose is preferably cellulose fiber. That is, in one aspect, the polypropylene-based resin composition according to the present embodiment has a plant-derived filler (D) that is cellulose fiber.

[0110] The wood powder is mainly finely crushed wood powder. Examples of the wood include, for example, hinoki, cedar, pine, elm, fir, oak, maple, sen, tamarack, oak, beech, oyster, cherry, photinia, camellia, cypress, oak, chestnut, hornbeam, dogwood, holly, elm, alder, rubber tree, lamine, lawan, terentang, mango, brickwood, lanshinbok, chatchinmodoki, nurude, urushi, hazenoki, harigiri, hannoki, kabanoki, asada, kixasage, tabebuia, ibe, gayakan, corizia, canarywood, canarium, Katsura, Terminalia, idigbo, afara, erima, meranti, parashipis, chengal, resak, apiton, kruin, yan, chutel, dona, kapul, yakal, melanch, upna, kaki tree, koktan, butabuta, kuri, bintangor, santa maria, carophyllum, geronggan, garcinia, manil, isnoki, walnut, nogurumi, nan, queensland walnut, bilian, tabunoki, greenheart acacia, kokrojua, african teak, afzelia, nemunoki, acre, albizia, false acacia, magnolia, honoki, kaya, mulberry, eucalyptus, plane tree, nanakamado, poplar, mokkok, keyaki, nire, teak, mafogany, ginkgo, hemlock, larch, ichii, kaya, etc.

[0111] The size of the plant-derived filler (D) is preferably 700 μm or less, more preferably 400 μm or less, and even more preferably 200 μm or less.

[0112] The plant-derived filler (D) 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.

[0113] Among the plant-derived fillers (D), the cellulose fibers 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-type pulverizer or extruder. Thereafter, the processed cellulose raw material is stirred using a medium-type pulverizer to obtain cellulose fibers.

[0114] The cellulose fibers are preferably biomass nanofibers. In this specification, the biomass nanofibers mean either long-fiber biomass nanofibers or short-fiber biomass nanofibers.

[0115] Examples of the biomass fibers include cellulose nanofibers, chitin nanofibers, chitosan nanofibers, silk nanofibers, etc. Among these, the biomass fibers are preferably cellulose nanofibers (CNF) from the viewpoints of chemical stability, thermal stability, and cost.

[0116] From the viewpoint of the aspect ratio, the average fiber diameter of the biomass fibers 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 = about 20) measured based on an electron micrograph taken at an appropriate magnification.

[0117] Examples of the biomass fibers include mechanically defibrated biomass fibers produced by mechanical defibration, chemically modified biomass nanofibers produced through chemical modification, etc. Among these, the biomass fibers are preferably mechanically defibrated biomass fibers.

[0118] Commercially available products may be used as the biomass fibers. Examples of commercially available biomass fibers include BiNFi-s (registered trademark) manufactured by Sugino Machine Limited.

[0119] From the viewpoint of improving fluidity, the content of the plant-derived filler (D) is 20% by mass or more and 70% by mass or less, preferably 25% by mass or more and 60% by mass or less, and more preferably 25% by mass or more and 55% by mass or less, based on the total content of (A), (B), (C) and (D) being 100% by mass. When the polypropylene-based resin composition contains two or more plant-derived fillers (D), the content of the plant-derived filler (D) is the total content thereof.

[0120] The polypropylene-based resin composition according to the present embodiment may further contain an olefin-based polymer other than the propylene-based polymer. The polypropylene-based resin composition may contain only one kind of the olefin-based polymer, or may contain two or more kinds of the olefin-based polymers in any proportion.

[0121] The content of the olefin-based polymer contained in the polypropylene-based resin composition according to the present embodiment may be more than 0% by mass and 40% by mass or less, preferably more than 0% by mass and 30% by mass or less, based on 100% by mass of the total mass of the polypropylene-based resin composition.

[0122] Examples of the olefin-based polymer include an ethylene-α-olefin copolymer containing a monomer unit derived from ethylene and a monomer unit derived from an α-olefin having 4 or more carbon atoms.

[0123] In the ethylene-α-olefin copolymer, the total content of the monomer unit derived from ethylene and the monomer unit derived from an α-olefin having 4 or more carbon atoms may be 95% by mass or more, preferably 98% by mass or more, more preferably 99% by mass or more, usually 100% by mass or less, and may be 100% by mass, based on 100% by mass of the total mass of the ethylene-α-olefin copolymer.

[0124] As the α-olefin having 4 or more carbon atoms in the ethylene-α-olefin copolymer, α-olefins having 4 to 12 carbon atoms (for example, 1-butene, 1-pentene, 1-hexene, 4-methyl-1-pentene, 1-octene and 1-decene) can be mentioned. The α-olefin having 4 or more carbon atoms is preferably 1-butene, 1-hexene, or 1-octene. The α-olefin having 4 or more carbon atoms may have a cyclic structure and be an α-olefin having 4 or more carbon atoms (for example, vinylcyclopropane, vinylcyclobutane).

[0125] The ethylene-α-olefin copolymer is preferably at least one copolymer selected from the group consisting of ethylene-1-butene copolymer, ethylene-1-hexene copolymer, ethylene-1-octene copolymer, ethylene-1-decene copolymer, ethylene-(3-methyl-1-butene) copolymer, and a copolymer of ethylene and an α-olefin having a cyclic structure, and more preferably an ethylene-1-butene copolymer.

[0126] The content of the monomer unit derived from the α-olefin having 4 or more carbon atoms in the ethylene-α-olefin copolymer may be 1% by mass or more and 49% by mass or less, preferably 5% by mass or more and 49% by mass or less, more preferably 24% by mass or more and 49% by mass or less, based on 100% by mass of the total mass of the ethylene-α-olefin copolymer.

[0127] The melt flow rate (MFR) of the ethylene-α-olefin copolymer is 0.1 g / 10 min or more and 80 g / 10 min or less. The MFR 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.

[0128] The density of the ethylene-α-olefin copolymer is 0.850 g / cm 3 or more and 0.890 g / cm 3It may be, preferably, 0.850 g / cm 3 or more and 0.880 g / cm 3 or less, more preferably 0.855 g / cm 3 or more and 0.870 g / cm 3 or less.

[0129] The ethylene-α-olefin copolymer can be produced by a commonly used method. For example, it can be produced by polymerizing ethylene and an α-olefin having 4 or more carbon atoms using a polymerization catalyst. As the polymerization catalyst, the polymerization catalyst already described for producing the propylene-based polymer may be used.

[0130] Commercially available products may be used as the ethylene-α-olefin copolymer. Examples of such commercially available products include "Engage (registered trademark) 7447" manufactured by Dow Chemical Japan Co., Ltd., "Tafmer (registered trademark)" manufactured by Mitsui Chemicals, Inc., "Neozex (registered trademark)" and "Ultrezex (registered trademark)" manufactured by Prime Polymer Co., Ltd., and "Exlan FX (registered trademark)", "Sumicasen (registered trademark)" and "Espren SPO (registered trademark)" manufactured by Sumitomo Chemical Co., Ltd.

[0131] [Other Additives] The polypropylene-based resin composition according to this embodiment may contain other additives as necessary. Examples of other additives include pigments, inorganic fillers, neutralizing agents, antioxidants, processing stabilizers, light stabilizers, ultraviolet absorbers, nucleating agents, clarifying nucleating agents, processing aids, metal soaps, foaming agents, antibacterial agents, plasticizers, flame retardants, crosslinking aids, brightening agents, etc.

[0132] The method for producing the polypropylene-based resin composition according to this embodiment is not particularly limited, and for example, it can be produced 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, etc.

[0133] The temperature of melt-kneading is preferably 150°C or higher and 230°C or lower, and the time of melt-kneading is preferably 0.5 minutes or longer and 5 minutes or shorter. Also, the melt-kneading of each component may be performed simultaneously or sequentially.

[0134] In melt-kneading, the rotation speed of the screw provided in the kneader is preferably 100 rpm or higher and 600 rpm or lower, and more preferably 150 rpm or higher and 500 rpm or lower.

[0135] The time of melt-kneading is preferably 0.5 minutes or longer and 5 minutes or shorter.

[0136] The polypropylene-based resin composition according to this embodiment may be formed into a molded article by using 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 methods for such molded articles include injection molding methods, press molding methods, vacuum molding methods, vacuum press molding methods, pressure air molding methods, foam molding methods, extrusion molding methods, and the like.

[0137] Examples of the uses of the molded article containing the polypropylene-based resin composition according to this embodiment include automotive interior and exterior members, household electric 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 household electric appliance part.

[0138] The present invention includes the following aspects. [1] A polypropylene-based resin (A), a modified polypropylene-based resin (B), an organically modified siloxane compound (C), and a plant-derived filler (D), with the total content of (A), (B), (C), and (D) being 100% by mass, the content of the polypropylene-based resin (A) being 5% by mass or more and 79.8% by mass or less, the content of the modified polypropylene-based resin (B) being 0.1% by mass or more and 10% by mass or less, The content of the organically modified siloxane compound (C) is 0.1% by mass or more and 15% by mass or less, and the content of the plant-derived filler (D) is 20% by mass or more and 70% by mass or less, a polypropylene-based resin composition. [2] The polypropylene-based resin (A) according to [1], wherein the polypropylene-based resin (A) contains one or more selected from the group consisting of a propylene homopolymer and a heterophasic propylene polymerization material. [3] The polypropylene-based resin composition according to [1] or [2], wherein the weight average molecular weight of the organically modified siloxane compound (C) is less than 90,000. [4] The polypropylene-based resin composition according to any one of [1] to [3], wherein the modified polypropylene-based resin (B) contains one or more selected from the group consisting of an acid-modified polypropylene-based polymer, a hydroxyl group-modified polypropylene-based polymer, an epoxy-modified polypropylene-based polymer, a carbodiimide-modified polypropylene-based polymer, and an oxazoline-modified polypropylene-based polymer. [5] The polypropylene-based resin composition according to any one of [1] to [4], wherein the organically modified siloxane compound (C) is an alkyl-modified siloxane compound. [6] The polypropylene-based resin composition according to any one of [1] to [5], wherein the content of the modifying group of the modified polypropylene-based resin (B) is 0.01% by mass or more and 3.4% by mass or less with respect to 100 parts by mass of the modified polypropylene-based resin (B). [7] The polypropylene-based resin composition according to any one of [1] to [6], wherein the intrinsic viscosity of the modified polypropylene-based resin (B) is 0.4 dl / g or more and 3.0 dl / g or less. [8] The polypropylene-based resin composition according to any one of [1] to [7], wherein the plant-derived filler (D) is cellulose fiber.

Examples

[0139] 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.

[0140] [Materials Used] In the examples and comparative examples, the following materials were used to prepare polypropylene-based resin compositions.

[0141] 1. Polypropylene-based resin (A) Polypropylene homopolymer 1 (Noblen HR100EG, manufactured by Sumitomo Chemical Co., Ltd.) · MFR (230 °C, load 2.16 kg): 23 - 25 g / 10 min

[0142] 2. Modified polypropylene-based resin (B) Maleic anhydride-modified polypropylene 1 (obtained by the method described in Synthesis Example 2 of International Publication No. 2020 / 009090) · Content of succinic anhydride residue: 0.11 mass% · Intrinsic viscosity: 0.8 dl / g

[0143] 3. Organically modified siloxane compound (C) Organically modified siloxane composition 1 (TEGOMER Antiscratch 100, manufactured by Evonik Industries AG, a masterbatch containing an alkyl-modified siloxane compound (C) and polypropylene, content of the organically modified siloxane compound in the masterbatch: about 50 mass%, weight average molecular weight of the cold xylene-soluble part of the masterbatch containing the organically modified siloxane compound (C) and polypropylene: 15,600)

[0144] 4. Plant-derived filler (D) Powdered cellulose 1 (KC Flock, W-100GK, manufactured by Nippon Paper Industries Co., Ltd.)

[0145] 5. Additives Antioxidant 1 (Irganox 1010, manufactured by BASF Japan Ltd.) Antioxidant 2 (Irgafos 168, manufactured by BASF Japan Ltd.)

[0146] The physical properties of each material used in the examples and comparative examples were measured by the following methods.

[0147] (Melt Flow Rate) 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.

[0148] (Intrinsic Viscosity) The intrinsic viscosity was determined by the "extrapolation method" in which the reduced viscosity was measured for multiple concentrations using an Ubbelohde viscometer, the reduced viscosity was plotted against the concentration, and the concentration was extrapolated 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, the reduced viscosity was plotted against the concentration, and it was determined by the method of extrapolating the concentration to zero.

[0149] <Example 1> 58.5% by mass of polypropylene homopolymer 1, 1.5% by mass of maleic anhydride-modified polypropylene 1, 10% by mass of organically modified siloxane composition 1 (of which the organically modified siloxane compound (C) is 5% by mass), and 30% by mass of powdered cellulose 1 were mixed to obtain a mixture. To 100 parts by mass of the obtained mixture, 0.2 part by mass of antioxidant 1 and 0.2 part by mass of antioxidant 2 were mixed to obtain a mixture. The obtained mixture was fed into a twin-screw extruder (KZW12TW manufactured by Techno Bel, L / D = 75), and melt-kneaded at a cylinder temperature of 180 °C and a screw rotation speed of 300 rpm, and pelletized to obtain the polypropylene-based resin composition of Example 1.

[0150] <Comparative Example 1> A polypropylene-based resin composition of Comparative Example 1 was produced in the same manner as in Example 1, except that the materials shown in Table 1 were used.

[0151] The MFR and impact strength in the polyolefin-based resin compositions obtained in the examples and comparative examples were measured by the following methods.

[0152] (Measurement of MFR (unit: g / 10 min)) Using the pellets of the polypropylene resin compositions obtained in the examples and comparative examples, in accordance with the method specified in JIS K7210, under the conditions of a temperature of 230 °C and a load of 2.16 kg, it was measured by Method A.

[0153] <Molding Method of Impact Strength Sample> Using the pellets of the polypropylene resin compositions obtained in the examples and comparative examples, with an SI-30III injection molding machine manufactured by Toyo Machine Metal Co., Ltd., injection molding was carried out at a molding temperature of 200 °C and a mold temperature of 50 °C. For the polypropylene resin compositions obtained in each example and comparative example, test pieces for physical property evaluation with a length of 80 mm × width of 10 mm × thickness of 4 mm were obtained.

[0154] <Notched Izod Impact Strength (unit: kJ / m 2 ) Measurement> Using the notched test pieces obtained by notching the test pieces for physical property evaluation as test pieces, the notched Izod impact strength was measured in accordance with the method specified in JIS K7110. The shape of the notch was Type A notch. Measurement temperature: 23 °C, -30 °C

[0155] The compounding amounts, MFR, and impact strengths of the polypropylene resin compositions of the examples and comparative examples are shown in Table 1.

[0156]

Table 1

[0157] As can be seen from the results in Table 1, the polypropylene resin composition of the example that satisfies all the constituent requirements of the present invention contains a plant-derived filler, maintains mechanical strength, and has relatively excellent fluidity.

Claims

1. A polypropylene resin (A), a modified polypropylene resin (B), an organically modified siloxane compound (C), and a plant-derived filler (D), with the total content of (A), (B), (C) and (D) being 100% by mass, the content of the polypropylene resin (A) being 5% by mass or more and 79.8% by mass or less, the content of the modified polypropylene resin (B) being 0.1% by mass or more and 10% by mass or less, the content of the organically modified siloxane compound (C) being 0.1% by mass or more and 15% by mass or less, and the content of the plant-derived filler (D) being 20% by mass or more and 70% by mass or less, a polypropylene resin composition.

2. The polypropylene resin composition according to claim 1, wherein the polypropylene resin (A) contains one or more selected from the group consisting of a propylene homopolymer and a heterophasic propylene polymerization material.

3. The polypropylene resin composition according to claim 1 or 2, wherein the weight average molecular weight of the organically modified siloxane compound (C) is less than 90,000.

4. The polypropylene resin composition according to claim 1 or 2, wherein the modified polypropylene resin (B) contains one or more selected from the group consisting of an acid-modified polypropylene polymer, a hydroxyl group-modified polypropylene polymer, an epoxy-modified polypropylene polymer, a carbodiimide-modified polypropylene polymer, and an oxazoline-modified polypropylene polymer.

5. The polypropylene resin composition according to claim 1 or 2, wherein the organically modified siloxane compound (C) is an alkyl-modified siloxane compound.

6. The polypropylene resin composition according to claim 1 or 2, wherein the modified group content of the modified polypropylene resin (B) is 0.01% by mass or more and 3.4% by mass or less based on 100% by mass of the modified polypropylene resin (B).

7. The polypropylene resin composition according to claim 1 or 2, wherein the intrinsic viscosity of the modified polypropylene resin (B) is 0.4 dl / g or more and 3.0 dl / g or less.

8. The polypropylene resin composition according to claim 1 or 2, wherein the plant-derived filler (D) is a cellulose fiber.

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