Flowability improver for resin composition, molded article and polyolefin resin

Abstract

To provide a polyolefin resin composition which is excellent in moldability while maintaining mechanical strength of a polyolefin resin.SOLUTION: The resin composition contains a polyolefin resin (A) and a rosin acid (B). The weight average molecular weight of the rosin acid (B) is 280-340, and the content of the rosin acid (B) is 0.1-5 pts.mass based on 100 pts.mass of the polyolefin resin (A).SELECTED DRAWING: None

Description

[Technical Field]

[0001] The present invention relates to a resin composition, a molded article, and a flowability improver for a polyolefin resin. [Background technology]

[0002] Polyolefin resins have excellent mechanical properties and are therefore processed into injection molded products, blow molded products, films, sheets, fibers, and the like, and are used for a variety of applications.

[0003] These polyolefin resins have excellent impact strength, but have poor fluidity when melted, which can cause problems such as melt fracture when molded at high speeds. For this reason, additives such as lubricants are usually added to the polyolefin resin to reduce the apparent flow viscosity when melted, improving moldability and increasing the extrusion rate, thereby improving productivity (Patent Document 1).

[0004] However, when conventional lubricants are used, there is a problem that, while the melt fluidity improves as the amount of lubricant increases, the mechanical strength of the polyolefin resin decreases. [Prior art documents] [Patent documents]

[0005] [Patent Document 1] Japanese Patent Application Laid-Open No. 2012-009754 Summary of the Invention [Problem to be solved by the invention]

[0006] The present invention has been made in view of the above circumstances, and an object of the present invention is to provide a polyolefin resin composition that has excellent moldability while maintaining the mechanical strength inherent to polyolefin resins.

[0007] Another object of the present invention is to provide a novel flowability improver that can improve the molding processability of polyolefin resins while maintaining the mechanical strength of the polyolefin resins. [Means for solving the problem]

[0008] As a result of extensive research, the present inventors have found that the above-mentioned problems can be solved by a composition containing a specific rosin acid in a specific amount in a polyolefin resin. The present inventors have also found that the above-mentioned problems can be solved by a flowability improver containing the specific rosin acid. Specifically, the present invention relates to the following resin composition, molded article, and flowability improver.

[0009] 1. A composition comprising a polyolefin resin (A) and a rosin acid (B), The rosin acid (B) has a weight average molecular weight of 280 to 340, A resin composition, wherein the content of the rosin acid (B) is 0.1 to 5 parts by mass per 100 parts by mass of the polyolefin resin (A).

[0010] 2. The resin composition according to item 1, wherein component (A) is at least one selected from the group consisting of polyethylene and polypropylene.

[0011] 3. The resin composition according to item 1 or 2, wherein the acid value of component (B) is 130 to 200 mgKOH / g.

[0012] 4. The resin composition according to any one of items 1 to 3, wherein component (B) is at least one selected from the group consisting of natural rosin, purified rosin, hydrogenated rosin, and disproportionated rosin.

[0013] 5. A molded article obtained from the resin composition according to any one of items 1 to 4 above.

[0014] 6. A flowability improver for polyolefin resins, comprising a rosin acid (B) having a weight-average molecular weight of 280 to 340.

[0015] 7. The flowability improver for polyolefin resin according to item 6, wherein the polyolefin resin is at least one selected from the group consisting of polyethylene and polypropylene.

[0016] 8. The flowability improver for polyolefin resin according to item 6 or 7, wherein the acid value of component (B) is 130 to 200 mgKOH / g.

[0017] 9. The flowability improver for polyolefin resin according to any one of items 6 to 9, wherein component (B) is at least one selected from the group consisting of natural rosin, purified rosin, hydrogenated rosin, and disproportionated rosin. [Effects of the Invention]

[0018] The resin composition of the present invention has excellent fluidity when melted while maintaining the mechanical strength of a polyolefin resin, and therefore has excellent molding processability. Furthermore, when used in a polyolefin resin, the flowability improver of the present invention improves the fluidity when melted while maintaining the mechanical strength of the polyolefin resin, thereby improving the molding processability. BEST MODE FOR CARRYING OUT THE INVENTION

[0019] [Resin composition] The resin composition of the present invention contains a polyolefin resin (A) (hereinafter also referred to as component (A)) and a rosin acid (B) (hereinafter also referred to as component (B)).

[0020] <Polyolefin resin (A)> The component (A) is not particularly limited, and various known components can be used. The component (A) may be used alone or in combination of two or more.

[0021] Examples of component (A) include homopolymers of α-olefins having about 2 to 8 carbon atoms, such as ethylene, propylene, and 1-butene; and binary or ternary (co)polymers of these α-olefins with other α-olefins having about 2 to 18 carbon atoms, such as ethylene, propylene, 1-butene, 3-methyl-1-butene, 1-pentene, 4-methyl-1-pentene, 4,4-dimethyl-1-pentene, 1-hexene, 4-methyl-1-hexene, 1-heptene, 1-octene, 1-decene, and 1-octadecene, or vinyl acetate.

[0022] Examples of component (A) include ethylene-based resins such as polyethylene, ethylene-propylene copolymer, ethylene-1-butene copolymer, ethylene-propylene-1-butene copolymer, ethylene-4-methyl-1-pentene copolymer, ethylene-1-hexene copolymer, ethylene-1-heptene copolymer, and ethylene-1-octene copolymer; propylene-based resins such as polypropylene, propylene-ethylene copolymer, propylene-ethylene-1-butene copolymer, propylene-ethylene-4-methyl-1-pentene copolymer, and propylene-ethylene-1-hexene copolymer; 1-butene-based resins such as 1-butene homopolymer, 1-butene-ethylene copolymer, and 1-butene-propylene copolymer; and 4-methyl-1-pentene-based resins such as 4-methyl-1-pentene homopolymer and 4-methyl-1-pentene-ethylene copolymer.

[0023] From the viewpoint of excellent moldability, component (A) is preferably a homopolymer of an α-olefin having about 2 to 8 carbon atoms, such as ethylene, propylene, or 1-butene; or a binary or ternary (co)polymer of the above α-olefin with another α-olefin having about 2 to 18 carbon atoms, such as ethylene, propylene, 1-butene, 3-methyl-1-butene, 1-pentene, 4-methyl-1-pentene, 4,4-dimethyl-1-pentene, 1-hexene, 4-methyl-1-hexene, 1-heptene, 1-octene, 1-decene, or 1-octadecene; and from the same viewpoint, at least one selected from the group consisting of polyethylene and polypropylene is more preferred.

[0024] In addition, if component (A) is a copolymer of the above-mentioned α-olefin and unsaturated carboxylic acid, or a salt of such a copolymer, molding processability will be reduced, which is not preferred. Examples of unsaturated carboxylic acids include acrylic acid, methacrylic acid, fumaric acid, maleic acid, and maleic anhydride.

[0025] <Rosin acid (B)> The component (B) is not particularly limited, and various known rosin acids can be used, so long as they are rosin acids having a weight-average molecular weight (Mw) of 280 to 340. The component (B) may be used alone or in combination of two or more.

[0026] The resin composition of the present invention, by using component (B), has improved fluidity when the resin composition is melted, resulting in excellent moldability, while maintaining the mechanical strength of component (A). When a rosin-based resin other than component (B) is used, such as a rosin ester, which is a reaction product of rosin acid and alcohol, or various metal salts of rosin acid, the resin composition does not have improved or even reduced fluidity when melted, and therefore does not have improved moldability.

[0027] Component (B) may be, for example, natural rosin (gum rosin, tall oil rosin, wood rosin) derived from Pinus massoniana, Slash pine (Pinus elliottii), Merkusii, Caribbean pine (Pinus caribaea), Sibo pine (Pinus kesiya), Loblolly pine (Pinus taeda), and Great King pine (Pinus palustris), refined rosin (hereinafter, natural rosin and refined rosin are collectively referred to as unmodified rosin), hydrogenated rosin, disproportionated rosin, etc. Ng et al. Examples include:

[0028] The purified rosin can be obtained using various known methods. Specifically, it can be obtained using various known purification methods, such as distillation, extraction, recrystallization, and adsorption. Examples of distillation methods include distilling the natural rosin at a temperature of approximately 200 to 300°C under a reduced pressure of approximately 0.01 to 3 kPa. Examples of extraction methods include dissolving the natural rosin in an alkaline aqueous solution, extracting the insoluble unsaponifiable matter with various organic solvents, and then neutralizing the aqueous layer. Examples of recrystallization methods include dissolving the natural rosin in an organic solvent as a good solvent, distilling off the solvent to obtain a concentrated solution, and then adding an organic solvent as a poor solvent. Examples of good solvents include aromatic hydrocarbon solvents such as benzene, toluene, and xylene, chlorinated hydrocarbon solvents such as chloroform, lower alcohols, ketones such as acetone, and acetate esters such as ethyl acetate. Examples of poor solvents include n-hexane, n-heptane, cyclohexane, and isooctane. The adsorption method may involve contacting the natural rosin in a molten state or in a solution state obtained by dissolving the natural rosin in an organic solvent with a porous adsorbent, such as activated carbon, metal oxides such as alumina, zirconia, silica, molecular sieves, zeolites, and microporous clay.

[0029] The purified rosin may be further subjected to the disproportionation and hydrogenation procedures described below, either singly or in combination of two or more thereof.

[0030] The disproportionated rosin can be obtained by various known means. Specifically, for example, it can be obtained by a method (disproportionation) in which the unmodified rosin is heated in the presence of a disproportionation catalyst. Examples of the disproportionation catalyst that can be used include supported catalysts such as palladium-carbon, rhodium-carbon, and platinum-carbon; metal powders such as nickel and platinum; and iodides such as iodine and iron iodide. The amount of the catalyst used is usually about 0.01 to 5 parts by mass, and preferably about 0.01 to 1 part by mass, per 100 parts by mass of the unmodified rosin. The reaction temperature is about 100 to 300°C, and preferably about 150 to 290°C.

[0031] The disproportionated rosin may be further subjected to the purification, disproportionation, and hydrogenation described below, either alone or in combination of two or more thereof.

[0032] The hydrogenated rosin can be obtained by various known means. Specifically, for example, it can be obtained by hydrogenating the unmodified rosin under known hydrogenation conditions. Examples of hydrogenation conditions include heating the unmodified rosin to about 100 to 300°C under a hydrogen pressure of about 2 to 20 MPa in the presence of a hydrogenation catalyst. Preferably, the hydrogen pressure is about 5 to 20 MPa and the reaction temperature is about 150 to 300°C. Various known hydrogenation catalysts can be used, such as supported catalysts and metal powders. Supported catalysts include palladium-carbon, rhodium-carbon, ruthenium-carbon, and platinum-carbon. Metal powders include nickel and platinum. Palladium-, rhodium-, ruthenium-, and platinum-based catalysts are preferred because they increase the hydrogenation rate of the unmodified rosin and shorten the hydrogenation time. The amount of the hydrogenation catalyst used is usually about 0.01 to 5 parts by mass, and preferably about 0.01 to 2 parts by mass, per 100 parts by mass of the unmodified rosin.

[0033] The hydrogenation may be carried out, if necessary, with the unmodified rosin dissolved in a solvent. The solvent used is not particularly limited, provided it is inert to the reaction and readily dissolves the raw materials and products. Specifically, for example, cyclohexane, n-hexane, n-heptane, decalin, tetrahydrofuran, dioxane, etc., can be used alone or in combination of two or more. The amount of solvent used is not particularly limited, but it is usually sufficient to use the solvent so that the solids content is 10% by mass or more, preferably in the range of about 10 to 70% by mass, relative to the unmodified rosin.

[0034] Furthermore, the hydrogenated rosin may be further subjected to the above-mentioned purification, hydrogenation and disproportionation procedures either alone or in combination of two or more thereof.

[0035] Furthermore, to improve the color tone of component (B), purified rosin, hydrogenated rosin, and disproportionated rosin may be further subjected to a dehydrogenation treatment. The dehydrogenation treatment is not particularly limited, and conventional conditions can be used. For example, component (B) is dehydrogenated in the presence of a dehydrogenation catalyst in a sealed vessel at an initial hydrogen pressure of less than 10 kg / cm², preferably less than 5 kg / cm², and at a reaction temperature of approximately 100 to 300°C, with a lower limit of 200°C and an upper limit of 280°C. There is no particular limitation on the dehydrogenation catalyst, and various known catalysts can be used. Preferred examples include palladium-, rhodium-, and platinum-based catalysts, which are typically supported on a carrier such as silica or carbon. The amount of the catalyst used is typically 0.01 to 5% by weight of component (B), with a lower limit of 0.05% by weight and an upper limit of 3% by weight.

[0037] The component (B) is preferably at least one selected from the group consisting of natural rosin, purified rosin, hydrogenated rosin and disproportionated rosin, in view of the excellent mechanical strength and moldability of the resin composition.

[0038] (Physical properties of rosin acid (B)) The weight average molecular weight (Mw) of the component (B) is 280 to 340. In this specification, the weight average molecular weight (Mw) is a value calculated as polystyrene by gel permeation chromatography (GPC).

[0039] When the weight average molecular weight of component (B) is 280 or more, the resin composition has excellent mechanical strength. When the weight average molecular weight of component (B) is 340 or less, the resin composition has excellent mechanical strength and molding processability. The weight average molecular weight of component (B) is preferably about 300 to 320, from the viewpoint of providing excellent mechanical strength and molding processability to the resin composition.

[0040] If the weight-average molecular weight of component (B) exceeds 340, the resin composition will have reduced moldability and mechanical strength. Examples of such rosin acids include rosins modified with unsaturated carboxylic acids such as acrylic acid, methacrylic acid, fumaric acid, maleic acid, and maleic anhydride (unsaturated carboxylic acid-modified rosins), and polymerized rosins.

[0041] The physical properties of component (B) are not particularly limited except for the weight-average molecular weight. The acid value of component (B) is preferably about 130 to 200 mgKOH / g in order to provide a resin composition with excellent mechanical strength and moldability, and more preferably about 150 to 195 mgKOH / g in order to provide a resin composition with excellent mechanical strength and moldability. In the present invention, the acid value is a value measured according to JIS K0070 or a value measured according to the method described in the Examples below.

[0042] The color tone of component (B) is preferably 8 Gardner or less, more preferably about 10 to 400 Hazen, and particularly preferably about 10 to 200 Hazen, in order to suppress coloration in the resin composition. In this specification, the color tone is measured in accordance with JIS K 0071-1 for Hazen units and JIS K 0071-2 for Gardner units.

[0043] Component (B) may contain various known additives as needed, as long as they do not impair the effects of the present invention. Examples of additives include dehydrating agents, weathering agents, antioxidants, UV absorbers, heat stabilizers, and light stabilizers. The above additives can be used alone or in combination of two or more.

[0044] (additives) The resin composition may contain additives as needed, as long as they do not impair the effects of the present invention. Examples of additives include flame retardants (e.g., phosphorus-containing epoxy resins, red phosphorus, phosphazene compounds, phosphates, phosphate esters, etc.), silicone oil, wetting and dispersing agents, antifoaming agents, defoaming agents, natural waxes, synthetic waxes, metal salts of straight-chain fatty acids, fatty acid amides, esters, paraffins, and other mold release agents, crystalline silica, fused silica, calcium silicate, alumina, calcium carbonate, talc, inorganic pigments, organic pigments, dehydrating agents, crystal nucleating agents, plasticizers, flow improvers other than component (B), weathering agents, antioxidants, ultraviolet absorbers, heat stabilizers, and light stabilizers.

[0045] Examples of the inorganic pigment include cadmium red, cadmium lemon yellow, cadmium yellow orange, titanium dioxide, carbon black, black iron oxide, and black complex inorganic pigments.

[0046] Examples of the organic pigment include aniline black, perylene black, anthraquinone black, benzidine-based yellow pigment, phthalocyanine blue, and phthalocyanine green.

[0047] (Content of each ingredient) The content of the component (B) in the resin composition is 0.1 to 5 parts by mass per 100 parts by mass of the component (A).

[0048] When the content of component (B) is 0.1 parts by mass or more per 100 parts by mass of component (A), the resin composition has excellent moldability.When the content of component (B) is 5 parts by mass or less per 100 parts by mass of component (A), the resin composition has excellent moldability and maintains its mechanical strength.

[0049] The content of the component (B) in the resin composition is preferably 0.3 to 2 parts by mass per 100 parts by mass of the component (A), in order to provide the resin composition with excellent mechanical strength and moldability.

[0050] The content of the additive in the resin composition is not particularly limited, but is usually 0.001 parts by mass or more, preferably 0.005 parts by mass or more, more preferably 0.01 parts by mass or more, per 100 parts by mass of the resin composition, and is usually 100 parts by mass or less, preferably 50 parts by mass or less.

[0051] (Method of producing resin composition) The method for producing the resin composition is not particularly limited, and various known methods can be used. Examples of methods for producing the resin composition include premixing component (A), component (B), and, if necessary, the additives using a mixer such as a tumbler mixer or a Henschel mixer, followed by melt-kneading using a mixer such as a Banbury mixer, a roll, a Brabender, a single-screw kneading extruder, a twin-screw kneading extruder, or a kneader. The melt-kneading temperature is not particularly limited, but is typically in the range of 170 to 300°C, preferably 180 to 250°C.

[0052] [Molded body] The molded article of the present invention can be obtained by molding the resin composition by any of various known molding methods. The shape of the molded article is not particularly limited and can be appropriately selected depending on the use and purpose of the molded article, and examples thereof include plate-like, plate-like, rod-like, sheet-like, film-like, cylindrical, ring-like, circular, elliptical, polygonal, irregular-shaped, hollow, frame-like, box-like, and panel-like shapes.

[0053] The method for molding the molded article is not particularly limited, and any conventionally known molding method can be used. Specific examples include injection molding, injection compression molding, extrusion molding, stretch film molding, inflation molding, profile extrusion, transfer molding, hollow molding, gas-assisted hollow molding, blow molding, extrusion blow molding, IMC (in-mold coating) molding, press molding, rotational molding, multilayer molding, two-color molding, insert molding, sandwich molding, foam molding, and pressure molding. Among these, injection molding is preferred. Examples of injection molding machines include known injection molding machines such as ultra-high-speed injection molding machines and injection compression molding machines.

[0054] The molded article can be suitably used in a wide range of applications, from household goods to industrial goods, for example, automotive interior materials, automotive materials such as outer panels and bumpers, electrical and electronic equipment, home appliance parts, office automation equipment, information terminal equipment, machine parts, packaging materials, construction materials, civil engineering materials, fishery materials, various containers, lighting equipment, films, sheets, fibers, and other industrial materials.

[0055] Examples of the electrical and electronic devices include display devices such as car navigation systems, personal computers, game consoles, televisions, and electronic paper, as well as display devices such as printers, copy machines, fax machines, electronic organizers and PDAs, electronic desk calculators, electronic dictionaries, cameras, video cameras, and DVDs, as well as mobile phones, tablet-type mobile devices, and touch panel-type mobile devices.

[0056] [Flow improver] The flowability improver of the present invention contains the above-mentioned component (B). When used in a polyolefin resin, the flowability improver of the present invention improves the flowability of the polyolefin resin when melted while maintaining the mechanical strength of the polyolefin resin, thereby improving its molding processability. When the flowability improver contains a rosin-based resin other than component (B), such as rosin esters, which are reaction products of rosin acid and alcohol, or various metal salts of rosin acid, the flowability of the polyolefin resin when melted cannot be improved or is reduced, making it impossible to improve its molding processability. Note that the flowability improver of the present invention is different from the above-mentioned resin composition.

[0057] The flowability improver can be used for various known polyolefin resins. Examples of the polyolefin resin include the above-mentioned component (A). The polyolefin resins may be used alone or in combination of two or more.

[0058] The polyolefin resin for which the flowability improver is used is preferably a homopolymer of an α-olefin having about 2 to 8 carbon atoms, such as ethylene, propylene, or 1-butene, from the viewpoint of excellent moldability; or a binary or ternary (co)polymer of the above α-olefin with another α-olefin having about 2 to 18 carbon atoms, such as ethylene, propylene, 1-butene, 3-methyl-1-butene, 1-pentene, 4-methyl-1-pentene, 4,4-dimethyl-1-pentene, 1-hexene, 4-methyl-1-hexene, 1-heptene, 1-octene, 1-decene, or 1-octadecene, and from the same viewpoint, at least one selected from the group consisting of polyethylene and polypropylene is more preferred.

[0059] The component (B) in the flow improver is preferably at least one selected from the group consisting of natural rosin, purified rosin, hydrogenated rosin, and disproportionated rosin, in view of the excellent mechanical strength and molding processability of the polyolefin resin.

[0060] The weight average molecular weight (Mw) of the component (B) in the flowability improver is 280 to 340. In this specification, the weight average molecular weight (Mw) is a polystyrene-equivalent value determined by gel permeation chromatography (GPC).

[0061] When the weight-average molecular weight of component (B) is 280 or more, the mechanical strength of the polyolefin resin is maintained. When the weight-average molecular weight of component (B) is 340 or less, the mechanical strength of the polyolefin resin is maintained while improving its molding processability. The weight-average molecular weight of component (B) is preferably about 300 to 320, in order to provide excellent mechanical strength and molding processability to the polyolefin resin.

[0062] If the weight-average molecular weight of component (B) exceeds 340, the molding processability and mechanical strength of the polyolefin resin will decrease. Examples of such rosin acids include rosins modified with unsaturated carboxylic acids such as acrylic acid, methacrylic acid, fumaric acid, maleic acid, and maleic anhydride (unsaturated carboxylic acid-modified rosins), and polymerized rosins.

[0063] The physical properties of component (B) in the flow improver are not particularly limited except for the weight average molecular weight. The acid value of component (B) is preferably about 130 to 200 mgKOH / g from the viewpoint of excellent mechanical strength and moldability of the polyolefin resin, and more preferably about 150 to 195 mgKOH / g from the same viewpoint. In the present invention, the acid value is a value measured according to JIS K0070 or a value measured by the method described in the examples below.

[0064] The color tone of the component (B) in the flowability improver is preferably 8 Gardner or less, more preferably about 10 to 400 Hazen, and particularly preferably about 10 to 200 Hazen, in order to suppress coloration of the polyolefin resin. In this specification, the color tone is measured in accordance with JIS K 0071-1 for Hazen units and JIS K 0071-2 for Gardner units.

[0065] The amount of the flow improver used is not particularly limited, but is preferably 0.1 to 5 parts by mass per 100 parts by mass of the polyolefin resin.

[0066] When the amount of the flowability improver used is 0.1 parts by mass or more per 100 parts by mass of the polyolefin resin, the molding processability of the polyolefin resin is better.When the amount of the flowability improver used is 5 parts by mass or less per 100 parts by mass of the polyolefin resin, the molding processability of the polyolefin resin is better and its mechanical strength is maintained.

[0067] The amount of the flow improver used is more preferably 0.3 to 2 parts by mass per 100 parts by mass of the polyolefin resin, in view of the excellent mechanical strength and molding processability of the polyolefin resin.

[0068] The flowability improver of the present invention may contain various known additives as needed, as long as the effects of the present invention are not impaired. Examples of additives include dehydrating agents, weathering agents, antioxidants, UV absorbers, heat stabilizers, and light stabilizers. The above additives can be used alone or in combination of two or more. The content of the above additives is not particularly limited, but is preferably 0.5 to 10 parts by mass per 100 parts by mass of the flowability improver.

[0069] The method of using the fluidity improver of the present invention is not particularly limited. For example, the fluidity improver is added to a mixer together with a polyolefin resin, and melt-kneaded in the mixer. Examples of the mixer include a Banbury mixer, a roll, a Brabender, a single-screw kneading extruder, a twin-screw kneading extruder, and a kneader. [Example]

[0070] The present invention will be described in more detail below by showing examples of the present invention. The examples are not limited to the examples. In the examples, "parts" and "%" respectively "Parts by mass" and "% by mass" are used.

[0071] (Production of Rosin Acid (B)) Manufacturing Example 1 Into a reaction vessel equipped with a stirrer, thermometer, reflux condenser, and nitrogen gas inlet tube was added 1,000 parts of gum rosin (acid value 172 mg KOH / g, softening point 75°C) and 0.3 parts of 5% palladium carbon (water content 50%) as a disproportionation catalyst. The mixture was stirred at 280°C for 4 hours under a nitrogen blanket to carry out a disproportionation reaction, yielding a Gardner disproportionated rosin (hereinafter referred to as component (B1)) with an acid value of 160 mg KOH / g, a weight-average molecular weight of 320, and a color tone of 6.

[0072] Manufacturing Example 2 A 3-liter autoclave was charged with 1,000 parts of gum rosin (acid value 171 mg KOH / g, softening point 76°C, color tone Gardner 6) and 2 parts of 5% palladium carbon (water content 50%) as a hydrogenation catalyst. After removing oxygen from the system, the system was pressurized with hydrogen at 100 kg / cm. 2 After pressurizing, the mixture was heated to 260°C with stirring and hydrogenated for 3 hours at the same temperature to obtain hydrogenated rosin. The hydrogenated rosin was then distilled under a nitrogen blanket at a reduced pressure of 3 mmHg to obtain purified hydrogenated rosin. 200 parts of the purified hydrogenated rosin and 0.1 parts of 5% palladium carbon (water content: 50%) were charged into a 1-liter shaking autoclave, and the system was purged with nitrogen to remove oxygen. The system was then heated to 250°C and dehydrogenated for 3 hours at the same temperature to obtain hydrogenated rosin (hereinafter referred to as component (B2)) with an acid value of 172.6 mgKOH / g, a weight-average molecular weight of 300, and a color tone of 80 Hazen.

[0073] (acid number) The acid values ​​of the components (B1) to (B2) and the components (b1) to (b3) were measured in accordance with JIS K 0070. The results are shown in Tables 1 and 2.

[0074] The acid value of component (b4) was measured by the following method, and the results are shown in Tables 1 and 2.

[0075] A solution was prepared by dissolving 0.3 g of component (b4) in 50 ml of acetone and adding 25 ml of 0.1 mol / L potassium hydroxide aqueous solution to the acetone solution. Next, the solution was left to stand for 10 minutes, and after adding 2-3 drops of phenolphthalein as an indicator, it was titrated with 0.1 mol / L hydrochloric acid. The acid value of component (b4) was calculated using the following formula from the amount of hydrochloric acid titrated and the above weight of component (b4). Acid value (mgKOH / g) = {25 - amount of hydrochloric acid titrated (ml)} × 5.611 / (b4) weight of component (g)

[0076] (color tone) The color tones of components (B1) and (B2) were measured in Hazen units according to JIS K 0071-1 and in Gardner units according to JIS K 0071-2.

[0077] (Measurement of weight average molecular weight (Mw)) The weight-average molecular weights (Mw) of the components (B1) to (B2) and the components (b1) to (b4) were calculated as polystyrene equivalent values ​​using gel permeation chromatography (GPC) based on a calibration curve of standard polystyrene. The GPC measurements were performed under the following conditions. The results are shown in Tables 1 and 2. Analytical equipment: HLC-8320 (manufactured by Tosoh Corporation) Columns: Three types of columns are connected: TSK guardcolumn HXL-L, TSK-GEL G2000HXL, and TSK-GEL G1000HXL. Eluent: tetrahydrofuran Injection sample concentration: 3 mg / mL Sample flow rate: 1.0 mL / min Reference flow rate: 0.5 mL / min Injection volume: 40μL Column temperature: 40℃ Detector: RI, UV (254 nm)

[0078] [Preparation of Resin Composition] Example 1 100 parts of polypropylene (manufactured by Japan Polypropylene Corporation, product name "Novatec PP MA3") (hereinafter referred to as PP) and 1 part of component (B1) were placed into a roller mixer-type kneading device (manufactured by Toyo Seiki Seisakusho, product name "Labo Plastomill Model 10C100") and kneaded for 5 minutes at a roller rotation speed of 40 rpm and a temperature of 190°C. The resulting kneaded product was then removed from the kneading device, hot-pressed at 200°C, and formed into a sheet with a thickness of 1.0 mm, which was then cut into 5 mm x 5 mm pieces using a cutter to obtain pellets (resin composition).

[0079] Example 2 A resin composition was obtained in the same manner as in Example 1, except that 1 part of the component (B2) was used instead of the component (B1).

[0080] Example 3 A resin composition was obtained in the same manner as in Example 1, except that 0.3 parts of the component (B1) was used.

[0081] Comparative Example 1 100 parts of PP were placed in a roller mixer type kneading device (manufactured by Toyo Seiki Seisakusho, Ltd., product name "Labo Plastomill Model 10C100") and kneaded for 5 minutes at a roller rotation speed of 40 rpm and a temperature of 190° C. Thereafter, the resulting kneaded product was removed from the kneading device, hot pressed at 200° C., and formed into a sheet with a thickness of 1.0 mm, which was then cut into 5 mm × 5 mm pieces using a cutter to obtain pellets (resin composition).

[0082] Comparative Example 2 Preparation was carried out in the same manner as in Example 1, except that in Example 1, component (B1) was replaced with one part of hydrogenated rosin ester (manufactured by Arakawa Chemical Industries, Ltd., product name "KE-311", weight average molecular weight 780, acid value 6 mgKOH / g) (hereinafter referred to as component (b1)), to obtain pellets (resin composition).

[0083] Comparative Example 3 Preparation was carried out in the same manner as in Example 1, except that in Example 1, component (B1) was replaced with one part of a hydrogenated acrylic acid-modified rosin (manufactured by Arakawa Chemical Industries, Ltd., product name "KE-604", weight average molecular weight 380, acid value 240 mgKOH / g) (hereinafter referred to as component (b2)), to obtain pellets (resin composition).

[0084] Comparative Example 4 Preparation was carried out in the same manner as in Example 1, except that in Example 1, one part of polymerized rosin (manufactured by Arakawa Chemical Industries, Ltd., trade name "R-140", weight average molecular weight 520, acid value 145 mgKOH / g) (hereinafter referred to as component (b3)) was used instead of component (B1), to obtain pellets (resin composition).

[0085] Comparative Example 5 Preparation was carried out in the same manner as in Example 1, except that in Example 1, 0.3 parts of maleic acid-modified rosin ester (manufactured by Arakawa Chemical Industries, Ltd., trade name "Marquid No. 32", weight average molecular weight 1,740, acid value 180 mgKOH / g) (hereinafter referred to as component (b4)) was used instead of component (B1), and pellets (resin composition) were obtained.

[0086] Example 4 100 parts of polyethylene (manufactured by Rhombic Corporation, product name "LLDPE RLL1BF") (hereinafter referred to as PE) and 1 part of component (B1) were placed into a roller mixer-type kneading device (manufactured by Toyo Seiki Seisakusho, product name "Labo Plastomill Model 10C100") and kneaded for 5 minutes at a roller rotation speed of 40 rpm and a temperature of 210°C. The resulting resin (composition) was then removed from the kneading device, hot-pressed at 180°C, and molded into a 1.0 mm thick sheet, which was then cut into 5 mm x 5 mm pieces using a cutter to obtain pellets.

[0087] Example 5 A resin composition was obtained in the same manner as in Example 4, except that 1 part of the component (B2) was used instead of the component (B1).

[0088] Example 6 A resin composition was obtained in the same manner as in Example 4, except that 0.3 parts of the component (B1) was used.

[0089] Comparative Example 6 100 parts of PE were placed in a roller mixer-type kneading device (manufactured by Toyo Seiki Seisakusho, Ltd., product name "Labo Plastomill Model 10C100") and kneaded for 5 minutes at a roller rotation speed of 40 rpm and a temperature of 210° C. Thereafter, the resulting kneaded product was removed from the kneading device, hot-pressed at 180° C. to form a sheet with a thickness of 1.0 mm, and cut into 5 mm × 5 mm pieces using a cutter to obtain pellets (resin composition).

[0090] Comparative Example 7 Pellets (resin composition) were obtained in the same manner as in Example 4, except that 1 part of the component (b1) was used instead of the component (B1).

[0091] Comparative Example 8 Pellets (resin composition) were obtained in the same manner as in Example 4, except that 1 part of the component (b2) was used instead of the component (B1).

[0092] Comparative Example 9 Pellets (resin composition) were obtained in the same manner as in Example 4, except that 0.3 parts of the component (b4) was used instead of the component (B1).

[0093] (Evaluation of molding processability) In accordance with JIS K 7210, the MFR of each pellet was measured under conditions of a temperature of 230°C and a load of 21.2 N (2.16 kg) for the pellets of Examples 1 to 3 and Comparative Examples 1 to 5, and a temperature of 190°C and a load of 21.2 N (2.16 kg) for the pellets of Examples 4 to 6 and Comparative Examples 6 to 9. The results are shown in Tables 1 and 2.

[0094] (Mechanical strength evaluation) The pellets (resin compositions) obtained above were placed in a 100 mm × 100 mm × 1.0 mm mold and press-molded at 200°C for Examples 1 to 3 and Comparative Examples 1 to 5, and at 180°C for Examples 4 to 6 and Comparative Examples 6 to 9, to obtain 1.0 mm thick resin sheets (molded articles). The resulting resin sheets were punched using a JIS K7139-A23 shaped punching blade to obtain dumbbell test pieces for measuring mechanical strength. These test pieces were subjected to a tensile test using a Shimadzu Corporation "Universal Testing Machine AGX-V" to measure the nominal strain at break (%). The results are shown in Tables 1 and 2.

[0095] [Table 1]

[0096] [Table 2]

[0097] The blending amounts in Tables 1 and 2 are in parts by mass. The abbreviations in Tables 1 and 2 are as follows: (Compound abbreviations and details) PP: Polypropylene, product name "Novatec PP MA3", manufactured by Japan Polypropylene Corporation PE: Polyethylene, product name "LLDPE RLL1BF", manufactured by Rhombic Co., Ltd.

Claims

1. A composition comprising a polyolefin resin (A) and a rosin acid (B), the rosin acid (B) has a weight average molecular weight of 280 to 340; the content of the rosin acid (B) is 1 to 5 parts by mass relative to 100 parts by mass of the polyolefin resin (A), The polyolefin resin (A) is at least one selected from the group consisting of polyethylene and polypropylene. Resin composition.

2. The resin composition according to claim 1, wherein the acid value of component (B) is 130 to 200 mg KOH / g.

3. 3. The resin composition according to claim 1, wherein the component (B) is at least one selected from the group consisting of natural rosin, purified rosin, hydrogenated rosin, and disproportionated rosin.

4. A molded article obtained from the resin composition according to any one of claims 1 to 3.

5. A flowability improver for polyolefin resins, comprising a rosin acid (B) having a weight-average molecular weight of 280 to 340, The polyolefin resin is at least one selected from the group consisting of polyethylene and polypropylene. Flow improver.

6. 6. The flowability improver for polyolefin resins according to claim 5, wherein the acid value of component (B) is 130 to 200 mg KOH / g.

7. 7. The flowability improver for polyolefin resins according to claim 5, wherein component (B) is at least one selected from the group consisting of natural rosin, purified rosin, hydrogenated rosin, and disproportionated rosin.

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