Polypropylene-based resin composition and molded article for automotive interior parts

Abstract

To provide a polypropylene resin composition having fogging and generation of aldehydes suppressed without impairing antistatic properties.SOLUTION: Provided is a propylene resin composition obtained by mixing 0.01 to 2.0 pts.mass of a quaternary ammonium salt represented by the following chemical formula (1) with 100 pts.mass of a propylene resin (A). (in the formula, R1 represents a hydrocarbon group derived from an aliphatic amine containing 3-20 mass% of an aliphatic amine having a carbon number of 10 or less, 20-70 mass% of a C12 aliphatic amine, 10-30 mass% of an aliphatic amine having a carbon number of 14, and 5-30 mass% of an aliphatic amine having a carbon number of C16 or more; R2 represents an alkyl group having a carbon number of 1-3; m and n represent average addition mole number of oxyethylene groups and each independently represent a number of 0.5 to 10; and R3 represents a C1-3 alkyl group.)SELECTED DRAWING: None

Description

Technical Field

[0001] The present invention relates to a polypropylene-based resin composition and a molded article for automotive interior parts formed by molding the same.

Background Art

[0002] Automotive interior materials are made by molding a resin composition in which an inorganic filler or rubber is added to a polypropylene resin. However, it is desired that dust does not adhere to the interior material after molding and at the time of delivery to the user. Since the adhesion of dust is mainly due to static electricity, in order to make it difficult to adhere, an antistatic agent is generally added to reduce the electrical resistance of the surface of the interior material and release the static electricity.

[0003] However, the antistatic agent is easily adsorbed by an inorganic filler such as talc, and it is difficult to exhibit antistatic performance. In order to improve the antistatic performance, if the addition amount of the antistatic agent is increased, when the indoor temperature of the automobile rises in summer or the like, the antistatic agent vaporizes and adheres to the front glass or the like, causing a problem called fogging in which the transparency of the glass is impaired. For these reasons, automotive interior materials are required to have no adhesion of dust to the surface of the interior material and further not to impair the transparency of the glass of the automobile due to the adhesion of the antistatic agent.

[0004] Patent Document 1 discloses a propylene-ethylene block copolymer (Component A) containing 5 to 20% by weight of a propylene-ethylene random copolymer part having an ethylene content of 25 to 75% by weight, 30 to 82 parts by weight, talc (Component B) 10 to 40 parts by weight, and an olefin-based elastomer (Component C) 8 to 30 parts by weight, a total of 100 parts by weight, and the total of Component B and Component C is 20 to 60 parts by weight. An antistatic agent (Component D) composed of a mixture of monoglycerin fatty acid ester, diglycerin fatty acid ester, and alkyldiethanolamine is blended in an amount of 0.3 to 0.45% by weight based on the composition, and a resin composition for automotive interior materials excellent in antistatic properties and fogging prevention properties is disclosed.

[0005] Patent Document 2 discloses a polypropylene resin composition characterized by containing (A) 50 to 90 parts by weight of a crystalline polypropylene resin, (B) 10 to 50 parts by weight of an inorganic filler, (C) 0 to 40 parts by weight of a rubber (wherein the total amount of components (A), (B) and (C) is 100 parts by weight), and (D) 0.01 to 3 parts by weight of diethanolamine palmitate.

[0006] Patent Document 3 discloses a polypropylene resin composition containing 100 parts by weight of a propylene polymerization material, 0.1 to 0.4 parts by weight of at least one ester compound selected from the group consisting of fatty acid esters of monoglycerin and fatty acid esters of diglycerin, 0.1 to 0.4 parts by weight of stearyldiethanolamine monostearate, 0.2 to 0.8 parts by weight of an antistatic agent, 0.01 to 0.4 parts by weight of N,N'-di(hydroxyethyl)alkylamide, and 0.01 to 0.3 parts by weight of a hindered amine light stabilizer.

Prior Art Documents

Patent Documents

[0007]

Patent Document 1

Patent Document 2

Patent Document 3

Summary of the Invention

Problems to be Solved by the Invention

[0008] However, the polypropylene resin compositions described in Patent Documents 1 to 3 above do not have sufficient anti-fogging properties, and the emission amounts of volatile organic compounds (VOCs), particularly aldehydes such as acetaldehyde and formaldehyde, are not satisfactory. The object of the present invention is to solve the problems in the prior art as described above, and it is an object to provide a polypropylene-based resin composition that suppresses the generation of fogging and aldehydes without impairing the antistatic property.

Means for Solving the Problems

[0009] As a result of intensive studies to solve the above problems, the present inventors have found that the structure and properties of the antistatic agent component are related to the generation of fogging and aldehydes, and have completed the present invention.

[0010] That is, the present invention is as follows. [1] Based on 100 parts by mass of the polypropylene-based resin (A), The following chemical formula (1): [Chemical formula] (In the formula, R 1 represents a hydrocarbon group derived from an aliphatic amine containing 3 to 20% by mass of an aliphatic amine having 10 or less carbon atoms, 20 to 70% by mass of an aliphatic amine having 12 carbon atoms, 10 to 30% by mass of an aliphatic amine having 14 carbon atoms, and 5 to 30% by mass of an aliphatic amine having 16 or more carbon atoms in the whole aliphatic amine, R 2 represents an alkyl group having 1 to 3 carbon atoms, m and n represent the average number of added moles of oxyethylene groups, and are each independently a number of 0.5 or more and 10 or less. R 3 represents an alkyl group having 1 to 3 carbon atoms.) A polypropylene-based resin composition obtained by blending 0.01 to 2.0 parts by mass of the quaternary ammonium salt (B) represented by . [2] The polypropylene-based resin composition according to [1], wherein the quaternary ammonium salt (B) is liquid at room temperature. [3] The polypropylene-based resin composition according to [1] or [2], further containing 0.01 to 2.0 parts by mass of a polyhydric alcohol fatty acid ester (C) based on 100 parts by mass of the polypropylene-based resin (A). 〔4〕The polypropylene-based resin composition according to 〔3〕, wherein the components (B) and (C) are blended in a total amount of 0.01 to 2.0 parts by mass. 〔5〕The polypropylene-based resin composition according to 〔1〕 to 〔4〕, wherein the mass ratio of the total of the component (B) to the component (C) is [(B) / (C)] = 100 / 0 to 1 / 99. 〔6〕A molded article for automotive interior parts formed by molding the polypropylene-based resin composition according to 〔1〕 to 〔5〕. 〔7〕The following chemical formula (2):

Chemical formula

Advantages of the Invention

[0011] The molded article formed by molding the polypropylene-based resin composition of the present invention can significantly suppress fogging and the generation of aldehydes while maintaining the antistatic property necessary to prevent the adhesion of dust and the like. Further, since it does not cause clouding due to bleed-out, it can be preferably used as an automotive interior part.

Modes for Carrying Out the Invention

[0012] Hereinafter, the present invention will be described in detail. As the polypropylene-based resin (A) constituting the polypropylene-based resin composition of the present invention, conventionally known polypropylene-based resins can be appropriately selected and used. Examples of such polypropylene-based resins (A) include a propylene homopolymer, a propylene·α-olefin random copolymer of propylene and another α-olefin other than propylene, and a propylene block copolymer. Further, the polypropylene-based resin (A) may be modified with a polar group-containing monomer such as maleic anhydride. The polypropylene-based resin (A) can be used alone or in combination of two or more.

[0013] Preferred polypropylene-based resins (A) include a propylene homopolymer, a propylene·α-olefin random copolymer containing 30% by weight or less, preferably 5% by weight or less of other α-olefin units, and a propylene block copolymer having an n-decane extraction amount of 10% by weight or less, particularly 8% by weight or less. The "α-olefin unit" means a structural unit derived from an α-olefin and constituting the polymer. In the present invention, α-olefins include ethylene.

[0014] As the other α-olefin forming the propylene·α-olefin random copolymer or the propylene block copolymer, α-olefins having 2 to 20 carbon atoms other than propylene are preferably mentioned. Specifically, ethylene, 1-butene, 1-pentene, 1-hexene, 1-heptene, 1-octene, 1-decene, 1-dodecene, 1-hexadecene, 4-methyl-1-pentene, etc. can be mentioned. These α-olefins can be used alone or in combination of two or more.

[0015] Propylene block copolymers are usually obtained by using a plurality of polymerization reactors connected in series. For example, a propylene homopolymer is produced in the polymerization reactor on the front stage side, and a propylene / α-olefin random copolymer rubber (typically, a propylene / ethylene random copolymer rubber) is produced in the polymerization reactor on the rear stage side in the presence of the propylene homopolymer. The propylene homopolymer and the propylene / α-olefin random copolymer rubber are uniformly mixed. When using a propylene block copolymer as the polypropylene resin (A), if there is sufficient copolymer rubber in the propylene block copolymer, the blending of the rubber component can be omitted.

[0016] The polypropylene resin (A) used in the present invention can be produced by a known method using a solid titanium catalyst or a metallocene catalyst known per se.

[0017] Also, the polypropylene resin (A) has a melt flow rate MFR (under 230 °C and 2.16 Kg load) measured in accordance with ASTM D1238, which is usually 0.1 to 300 g / 10 min, preferably 1 to 100 g / 10 min, and more preferably 50 g / 10 min.

[0018] The quaternary ammonium salt (B) used in the present invention is a compound represented by the following chemical formula (1).

Chemical formula

[0019] R in formula (1) 1 Examples of the aliphatic amine having 10 or less carbon atoms contained in the aliphatic amine constituting 1 include octylamine and decylamine, and they are contained in the total aliphatic amine in an amount of 3 to 20% by mass, preferably 5 to 15% by mass. Examples of the aliphatic amine having 12 carbon atoms include dodecylamine (laurylamine), and it is contained in the total aliphatic amine in an amount of 20 to 70% by mass, preferably 30 to 60% by mass. Examples of the aliphatic amine having 14 carbon atoms include tetradecylamine, and it is contained in the total aliphatic amine in an amount of 10 to 30% by mass, preferably 15 to 20% by mass. Examples of the aliphatic amine having 16 or more carbon atoms include hexadecylamine, octadecylamine (stearylamine), eicosylamine, docosylamine (behenylamine), octadecenylamine, and oleylamine, and they are contained in the total aliphatic amine in an amount of 5 to 30% by mass, preferably 10 to 25% by mass. Among them, oleylamine is preferable from the viewpoint that the aliphatic amine is liquid at room temperature and the antistatic property and fogging resistance are improved.

[0020] As the mixture of aliphatic amines having the above composition, aliphatic amines derived from a plurality of fatty acids contained in natural oils and fats such as coconut oil, palm kernel oil, aburaage seed oil, inugashi seed oil, kagonoki seed oil, kuromoji seed oil, shirodamo seed oil, tabunoki seed oil, nikkei seed oil, and hamibia seed oil can be preferably used, but those prepared by combining aliphatic amines purified to a high purity in advance may also be used.

[0021] In formula (1), m and n represent the average number of moles of oxyethylene groups added. From the viewpoints of being liquid at a high concentration and improving the antistatic performance and fogging resistance, each is independently 0.5 or more, preferably 1.0 or more, and from the same viewpoints, it is 10 or less, preferably 5 or less, more preferably 1.5 or less.

[0022] Also, from the viewpoint of improving the antistatic performance and the fogging resistance, m + n is 1 or more, preferably 1.5 or more, and from the same viewpoint, it is 20 or less, preferably 5 or less, more preferably 3 or less.

[0023] R in formula (1) 2 and R 3 represent an alkyl group having 1 to 3 carbon atoms. For example, a methyl group, an ethyl group, a propyl group, etc. can be mentioned, but the most preferable is an ethyl group.

[0024] There is no particular limitation on the method for producing the quaternary ammonium salt (B) used in the present invention. For example, it can be produced by reacting a polyoxyethylene aliphatic amine (b1) obtained by adding ethylene oxide to the aliphatic amine with a dialkyl sulfate (b2).

[0025] Examples of the polyoxyethylene aliphatic amine (b1) include a mixture of aliphatic amines selected from the group consisting of octyldiethanolamine, decyldiethanolamine, lauryldiethanolamine, myristyldiethanolamine, palmityldiethanolamine, stearyldiethanolamine, and oleoyldiethanolamine, coconut alkyl diethanolamine, polyoxyethylene cocoamine, etc., but are not limited thereto.

[0026] Examples of the dialkyl sulfate (b2) include dimethyl sulfate, diethyl sulfate, dipropyl sulfate, etc., but are not limited thereto.

[0027] When reacting the polyoxyethylene aliphatic amine (b1) with the dialkyl sulfate (b2), the reaction temperature is preferably 50°C or higher, more preferably 60°C or higher, and preferably 100°C or lower, more preferably 90°C or lower, still more preferably 80°C or lower, from the viewpoint of allowing the reaction to proceed promptly.

[0028] The reaction molar ratio of polyoxyethylene aliphatic amine (b1) and dialkyl sulfate (b2) is preferably (b2) / (b1) = 0.1 to 1.2, more preferably 0.5 to 1.0, and even more preferably 0.7 to 1.0. In particular, when the reaction molar ratio is 1 or less, the viscosity decreases due to the influence of unreacted compounds, and it migrates to the surface, making it easier for the antistatic property to take effect.

[0029] The quaternary ammonium salt (B) used in the present invention is excellent in antistatic property and antifogging property, and thus can be suitably used as an antistatic agent for automotive interior materials. When the quaternary ammonium salt (B) is solid or gel-like at room temperature, the antifogging property tends to decrease, so it is preferably liquid at room temperature. Room temperature in this case is 25°C. In addition, the "quaternary ammonium salt (B)" in the present invention includes, in addition to those consisting only of the quaternary ammonium salt represented by the general formula (1), reaction mixtures containing unreacted raw materials, side reaction products, decomposition products, etc. remaining in the production process.

[0030] In the present invention, the blending amount of the quaternary ammonium salt (B) is 0.01 to 2.0 parts by mass with respect to 100 parts by mass of the polypropylene-based resin (A), but from the viewpoints of antistatic property and antifogging property, it is preferably blended at a ratio of 0.1 to 1.0 parts by mass, and even more preferably 0.2 to 0.5 parts by mass.

[0031] In the polypropylene-based resin composition of the present invention, in order to enhance the antistatic effect, a polyhydric alcohol fatty acid ester (C) can be blended as needed. The polyhydric alcohol fatty acid ester (C) is an ester compound obtained by a known method such as an esterification reaction of a polyhydric alcohol and a fatty acid, or a transesterification reaction of a polyhydric alcohol and a lower alkyl alcohol ester of a fatty acid.

[0032] Examples of the polyhydric alcohol serving as a raw material for the polyhydric alcohol fatty acid ester (C) include glycerin, trimethylolpropane, erythritol, pentaerythritol, sorbitan, diglycerin, xylitol, triglycerin, sorbitol, dipentaerythritol, inositol, tetraglycerin, etc. Among these, glycerin, diglycerin, sorbitan, and sorbitol are preferable.

[0033] From the viewpoint of imparting appropriate bleeding properties, the fatty acid serving as a raw material for the polyhydric alcohol fatty acid ester (C) preferably has 10 or more carbon atoms, more preferably 12 or more carbon atoms. Also, the number of carbon atoms is preferably 22 or less, more preferably 20 or less, and even more preferably 18 or less. Examples of the fatty acid having 8 to 22 carbon atoms include saturated fatty acids such as caprylic acid, capric acid, lauric acid, myristic acid, palmitic acid, stearic acid, 12-hydroxystearic acid, arachidic acid, behenic acid, etc., and unsaturated fatty acids such as decenoic acid, undecenoic acid, dodecenoic acid, tetradecenoic acid, oleic acid, erucic acid, linoleic acid, linolenic acid, ricinoleic acid, etc. Among these, lauric acid, myristic acid, palmitic acid, and stearic acid are preferable from the viewpoints of antistatic properties and bleeding properties, and palmitic acid and stearic acid are particularly preferable.

[0034] Among the polyhydric alcohol fatty acid esters (C), monoglycerin fatty acid esters, diglycerin fatty acid esters, and polyoxyalkylene sorbitan fatty acid esters are also preferable from the viewpoint of VOC reduction.

[0035] The monoglycerin fatty acid ester is an ester compound obtained by a known method such as an esterification reaction between monoglycerin and a fatty acid, or a transesterification reaction between monoglycerin and a lower alkyl alcohol ester of a fatty acid. Preferably, it is a monofatty acid ester compound of monoglycerin obtained from monoglycerin and a fatty acid having 8 to 22 carbon atoms, but a di-fatty acid ester or a tri-fatty acid ester may be present. These may be distilled or used as they are without distillation.

[0036] The diglycerin fatty acid ester is an ester compound obtained by a known method such as an esterification reaction of diglycerin and a fatty acid, or a transesterification reaction of diglycerin and a lower alkyl alcohol ester of a fatty acid, and is preferably a monofatty acid ester compound of diglycerin obtained from diglycerin and a fatty acid having 8 to 22 carbon atoms, but a di-fatty acid ester or a tri-fatty acid ester may be present. These may be distilled or used as they are without distillation.

[0037] The raw material diglycerin preferably has a diglycerin content of 90% by mass or more in which 2 moles of glycerin are condensed, but polyglycerin in which 3 moles or 4 moles are condensed may be present. As the fatty acid having 8 to 22 carbon atoms, the same one as the monoglycerin fatty acid ester can be used.

[0038] The polyoxyalkylene sorbitan fatty acid ester used in the present invention can be obtained, for example, by adding an alkylene oxide to a sorbitan fatty acid ester which is a partial ester of sorbitol or sorbitan and a fatty acid, but is not particularly limited thereto, and may be a reaction product obtained by esterifying a product obtained by adding an alkylene oxide to sorbitol or sorbitan and a fatty acid.

[0039] In the present invention, the blending amount of the polyhydric alcohol fatty acid ester (C) is preferably 0 to 2.0 parts by mass, more preferably 0.01 to 1.0 parts by mass, and still more preferably 0.1 to 0.5 parts by mass, based on 100 parts by mass of the polypropylene-based resin (A) from the viewpoints of antistatic properties and fogging prevention properties.

[0040] From the perspective of imparting an excellent antistatic effect to the polypropylene-based resin composition, the total amount of the components (B) and (C) contained in the polypropylene-based resin composition of the present invention is preferably in the range of 0.1 to 2.0 parts by mass, more preferably 0.2 to 0.5 parts by mass, based on 100 parts by mass of the polypropylene-based resin. By setting it within this range, the surface specific resistance value (LogΩ / □) can be 13 or less, and the fogging and increase in VOC generated by containing a surfactant can be reduced more, which is preferable.

[0041] The mass ratio of the component (B) to the total of the component (C) is preferably (B) / (C) = 100 / 0 to 1 / 99, more preferably 80 / 20 to 51 / 49, and even more preferably 80 / 20 to 70 / 30 in terms of imparting antistatic properties. Also, from the perspective of VOC, it is preferably 5 / 95 to 49 / 51, more preferably 5 / 95 to 30 / 70.

[0042] An inorganic filler can be blended in the polypropylene resin composition of the present invention to reinforce and increase the amount of the polypropylene resin composition. The inorganic filler is not particularly limited, and examples thereof include talc, calcium carbonate, barium sulfate, aluminum hydroxide, gypsum, dawsonite, shungite, radiolite, celite, novasite, asbestos, alumina, atavartite, kaolin clay, volcanic ash, silica, wollastonite, diatomaceous earth, magnesium oxide, magnesium carbonate, feldspar powder, biotite, magnesium silicate, and the like. Among them, the use of talc is preferable. These inorganic fillers may be used alone or in combination of two or more.

[0043] In the polypropylene resin composition of the present invention, various rubber components can be blended in order to impart flexibility, impact resistance, etc. to the composition. The rubber component is not particularly limited, and examples thereof include ethylene·α-olefin copolymer rubber, ethylene·α-olefin·non-conjugated diene copolymer rubber, natural rubber, isoprene rubber, polybutadiene rubber, isobutylene·isoprene copolymer rubber, acrylonitrile·butadiene copolymer rubber, styrene·butadiene copolymer rubber, styrene·isoprene copolymer rubber, silicone rubber, acrylic rubber, chloroprene rubber, and hydrogenated products of the above rubbers. Among them, the use of ethylene·α-olefin copolymer rubber and ethylene·α-olefin·non-conjugated diene copolymer rubber (hereinafter, when referred to as "ethylene-based copolymer rubber", both are meant) is preferred. The above rubbers can be used alone or in combination of two or more.

[0044] Hereinafter, the ethylene-based copolymer rubber preferably used as the rubber component will be described. Examples of the α-olefin copolymerized with ethylene, preferably an α-olefin having 3 to 10 carbon atoms, include propylene, 1-butene, 1-pentene, 1-hexene, 1-octene, 1-decene, and the like. These α-olefins can be used in combination of two or more. The content of the ethylene component in the ethylene-based copolymer rubber is 60 to 90 mol%, preferably 70 to 85 mol% from the viewpoint of impact resistance.

[0045] Examples of the non-conjugated diene include dicyclopentadiene, 1,4-hexadiene, 1,9-decadiene, cyclooctadiene, norbornadiene, methylene norbornene, ethylidene norbornene, 7-methyl-1,6-octadiene, and the like.

[0046] The iodine value of the ethylene·α-olefin·non-conjugated diene copolymer is preferably 5 to 50, more preferably 10 to 45. The Mooney viscosity (ML 1+4 , 100 °C) of the ethylene-based copolymer rubber is 10 to 100, preferably 20 to 60 from the viewpoints of dispersibility and impact resistance with the polypropylene resin.

[0047] The ethylene-based copolymer rubber can be obtained by copolymerization by a known polymerization method, for example, in the presence of a vanadium-based, titanium-based, or metallocene-based catalyst.

[0048] In each process until a molded body is produced from the polypropylene-based resin, within a range that does not significantly impair the effects of the present invention, depending on the purpose of use, poly-4-methyl-1-pentene, polystyrene, polybutadiene, or a styrene graft polymer of polyisoprene and a copolymer elastomer obtained by hydrogenating them, a polyester, a polyamide, a polycarbonate, or other high molecular weight polymers such as these may be added. The blending amount of these high molecular weight polymers is usually up to 5% by mass, preferably up to 3% by mass.

[0049] In the polypropylene-based resin composition of the present invention, in addition to the above polypropylene-based resin, other polymers or elastomers, antistatic agents, and inorganic fillers, within a range that does not significantly impair the effects of the present invention, depending on the purpose of use, stabilizers against heat, oxygen, light, etc. widely used in the fields of synthetic resins and synthetic rubbers, weathering agents, crystal nucleating agents, lubricants, flame retardants, plasticizers, and other additives may be added. In the present invention, a pigment may be further blended into the polypropylene-based resin containing these stabilizers or various additives.

[0050] Examples of stabilizers against heat and oxygen include phenolic antioxidants, phosphorus-based antioxidants, sulfur-based antioxidants, etc. Examples of weathering agents for preventing deterioration by light include various compounds such as amine-based, triazole-based, benzophenone-based, benzoate-based, nickel-based, and salicylate-based compounds. Examples of crystal nucleating agents include sorbitol-based, phosphorus-based, rosin-based, organic phosphate metal salts, carboxylic acid metal salts, etc. Examples of lubricants include fatty acid amides, higher alcohols, polyethylene wax, etc. Examples of flame retardants include phosphate-based, melamine-based, phosphorus-based, halogen-based, non-halogen-based compounds, etc. Examples of plasticizers include phthalate-based, fatty acid-based, adipate-based, trimellitate-based, epoxy-based, polyester-based compounds.

[0051] Examples of the pigment include inorganic pigments or organic pigments. Inorganic pigments have an inorganic coloring part and include those composed of simple elements as components, and oxides, sulfides, sulfates, etc. of Zn, Pb, Ti, Sb, Cd, Fe, As, Mg, Al, Co, Cr, etc. Organic pigments have an organic compound coloring part and include azo pigments, polyazo pigments, anthraquinone pigments, copper phthalocyanine pigments, dioxane pigments, quinacridone pigments, etc. For the purpose of improving the dispersibility of the pigment in polypropylene, a dispersion aid (examples include fatty acid metal salts, naphthenic acid metal salts, surfactants, silicone oil, lecithin, etc.) may be used.

[0052] When the polypropylene resin composition of the present invention is made into a molded article, it can be produced by blending the components (B) to (C) according to the present invention with the polypropylene resin as the main component by a normal method. Further, other polymers, inorganic fillers, pigments, and other additives may be blended. For example, the components (B) to (C) according to the present invention, and if necessary, inorganic fillers, pigments, and other additives are blended into powdery or pelletized polypropylene resin and other polymers, and after mixing with a Henschel mixer, tumbler mixer, etc., they are melt-kneaded with a single-screw or twin-screw kneading extruder and pelletized. The pellets thus obtained are processed into a molded article by an injection molding machine. If the MFR of the polypropylene resin composition is less than 5 g / 10 min, the moldability in injection molding is poor and it is not suitable for use as automotive interior parts. Also, when it exceeds 150 g / 10 min, the impact resistance is inferior and it is not suitable for use as automotive interior parts.

[0053] The molded article of the present invention is a molded article obtained by molding the polypropylene resin composition of the present invention by a known molding method, and examples include injection molded articles, press molded articles, vacuum molded articles, vacuum press molded articles, pressure air molded articles, foam molded articles, extrusion molded articles, etc.

[0054] As the molded article of the present invention, an injection molded article is preferred. Examples of the injection molding method include a general injection molding method, an injection foam molding method, a supercritical injection foam molding method, a super high-speed injection molding method, an injection compression molding method, an injection press molding method, a gas assist injection molding method, a sandwich molding method, a sandwich foam molding method, an insert / outset molding method, and the like.

[0055] As the use of the molded article of the present invention, automotive interior parts are preferred, and examples include door trims, pillars, instrument panels, consoles, rocker panels, armrests, door panels, spare tire covers, and the like.

[0056] The molded article for automotive interior parts of the present invention can be manufactured by injection molding the above polypropylene-based resin composition. The molding temperature is generally 150 to 350°C, preferably 170 to 250°C. If the molding temperature exceeds 350°C, it will cause deterioration of the resin composition and molding defects. If it is lower than 150°C, appearance defects and molding defects will occur. Regarding the mold temperature, it is preferably carried out in the range of 10 to 60°C. If the mold temperature exceeds 60°C, the surface finish degree of the molded article is excellent and a molded article with excellent rigidity can be obtained, but the molding cycle becomes long and the productivity decreases. On the contrary, if the mold temperature is set lower than 10°C, warping and shrinkage become remarkable, making it difficult to obtain a satisfactory molded article, and dew condensation is likely to occur on the mold, which causes the progress of mold corrosion. It is also not suitable from the perspective of energy cost related to cooling.

Examples

[0057] Next, the present invention will be described with reference to examples, but the present invention is not limited to the examples. Unless otherwise specified, the blending amounts are shown in parts by mass.

[0058] [Method for Producing Compound B] [Production Example 1: Synthesis of Quaternary Ammonium Salt (1)] 287 g of coconut alkyl diethanolamine was placed in a 500 mL four-necked flask, and the temperature was raised to 60 °C under nitrogen bubbling. Then, 154 g of diethyl sulfate (the reaction molar ratio of coconut alkyl diethanolamine to diethyl sulfate was 1.0) was added dropwise from a dropping funnel over 120 minutes, and the mixture was reacted for 60 minutes after the addition was complete to obtain a quaternary ammonium salt (1) composed of a yellow to reddish-brown transparent liquid.

[0059] [Production Examples 2-9: Synthesis of Quaternary Ammonium Salts (2)-(9)] As shown in Table 1, except for changing the type of aliphatic amine, the number of moles of ethylene oxide added, and the alkylating agent, the quaternary ammonium salts (2)-(9) of the present invention and the comparative examples were produced by the same procedure as in Production Example 1.

[0060] [Table 1]

[0061] [Production of Injection Molded Bodies] Examples 1-8 and Comparative Examples 1-5 Using Novatec MA1B manufactured by Japan Polypropylene Corporation as the polypropylene resin (A), the components (B)-(C) and other components of the types and amounts shown in Tables 2 and 3 below were blended in a twin-screw extruder (TEM26SS manufactured by Toshiba Machine Co., Ltd.) and melt-kneaded (screw rotation speed: 250 rpm, cylinder temperature: 200 °C). The extrudate was cooled and solidified with cold water and cut to obtain resin component compound pellets. The prepared compound was molded into a flat test plate 150 mm × 150 mm × 3 mm at a molding temperature of 190 °C using a hybrid injection molding machine FNX140 manufactured by Nissei Plastic Industrial Co., Ltd.

[0062] The measurement and evaluation of each evaluation item were carried out by the following methods. The results are shown in Tables 2 and 3.

[0063] (1) Evaluation of Antistatic Property After leaving the prepared test plates at 23°C and 50% humidity for 14 days, the surface resistivity was determined using the High Resista UP MCP-HT450 manufactured by Mitsubishi Chemical Analytech Co., Ltd. Here, based on past findings, the surface resistivity effective for preventing dust and dirt from adhering to the molded product was set to 13.0 (logΩ / □) or less.

[0064] (2) Evaluation of anti-fogging property Two pieces of 25 mm × 100 mm × 3 mmt were cut out from the test plates to be used as samples for anti-fogging property evaluation. The anti-fogging property evaluation was carried out using a fogging tester (constant temperature oil bath) manufactured by Thomas Scientific at a heating temperature of 100°C and a heating time of 20 hours in a glass container. After the heat treatment was completed, the glass plate with fogging adhered was taken out, left at 23°C and 50% humidity for 1 hour, and then the total light transmittance of the glass plate was measured using a haze meter HM-150 L2 type manufactured by Murakami Color Technology Research Co., Ltd. to evaluate the anti-fogging property. Here, the fogging property that does not interfere with visibility when riding in a vehicle was set to less than 5%.

[0065] (3) Evaluation of bleeding property The test pieces were placed in an oven set at 40°C for 200 hours, taken out, and then the appearance was visually observed and evaluated according to the following criteria. ○: Bleeding is not visually observed. △: Bleeding is visually observed. ×: Bleeding is easily visually observed and cannot be used in practice. The observation results of the bleeding property of each test piece are shown in Table 1.

[0066] (4) Acetaldehyde and formaldehyde emission amounts For the measurement of the acetaldehyde emission amount, test pieces were cut out from the flat molded body obtained by the above [Manufacture of injection molded body] to a size of 80 mm × 100 mm and used for measurement by the following method. (i) The test pieces were enclosed in a sampling bag with a volume of 10 L and filled with pure nitrogen gas. Then, the operation of replacing the gas in the sampling bag with nitrogen gas by removing the pure nitrogen gas was repeated twice. (ii) Fill the sampling bag with 4 L of pure nitrogen gas and close the cock of the sampling bag. Place the sampling bag in the oven, attach a sampling Teflon (registered trademark) tube to the tip of the cock and extend it outside the oven, and perform a heat treatment at 65 °C for 2 hours in this state.

[0067] (iii) Collection and measurement of acetaldehyde and formaldehyde While maintaining the sample gas prepared in (ii) at a heated state of 65 °C, after collecting 1 L into the simulated adsorption tube, collect the remaining sample gas at a collection rate of 0.4 L / min into a 2,4-dinitrophenylhydrazine (abbreviation: DNPH) cartridge until the whole amount is collected. After collection, the cartridge was subjected to elution treatment with acetonitrile, and the obtained eluate was measured for the components eluted from the cartridge using a high performance liquid chromatograph (HPLC; manufactured by Waters, model: Ultra Performance Liquid Chromatography Aquiy).

[0068] The emission amounts of acetaldehyde and formaldehyde (the amount of acetaldehyde and formaldehyde emitted from one test piece of a predetermined size, unit: μg / test piece) were calculated using the calibration curve of the standard substance of the component.

[0069]

Table 2

[0070]

Table 3

[0071] As shown in Table 2, the polypropylene resin compositions of Examples 1 to 8 were all excellent in antistatic properties and bleed prevention properties. In addition, fogging and the generation of aldehydes could be significantly suppressed. On the other hand, as shown in Table 3, the polypropylene resin compositions of Comparative Examples 1 to 5 were found to have poor antistatic properties, and the occurrence of fogging and aldehydes was observed.

Claims

1. Based on 100 parts by mass of polypropylene resin (A), the quaternary ammonium salt (B) represented by the following chemical formula (1): 【Chemical 1】 (In the formula, R １ represents a hydrocarbon group derived from an aliphatic amine containing 3 to 20% by mass of an aliphatic amine having 10 or less carbon atoms, 20 to 70% by mass of an aliphatic amine having 12 carbon atoms, 10 to 30% by mass of an aliphatic amine having 14 carbon atoms, and 5 to 30% by mass of an aliphatic amine having 16 or more carbon atoms in the total aliphatic amine, R ２ represents an alkyl group having 1 to 3 carbon atoms, and m and n represent the average number of moles of oxyethylene groups added, and are each independently a number of 0.5 or more and 10 or less. R ３ represents an alkyl group having 1 to 3 carbon atoms.) is blended in an amount of 0.01 to 2.0 parts by mass to form a polypropylene resin composition.

2. The polypropylene resin composition according to Claim 1, wherein the quaternary ammonium salt (B) is liquid at 25°C.

3. Based on 100 parts by mass of polypropylene resin (A), further a polyhydric alcohol fatty acid ester (C) is blended in an amount of 0.01 to 2.0 parts by mass, and the polypropylene resin composition according to Claim 1 or 2 is obtained.

4. The polypropylene resin composition according to Claim 3, wherein based on 100 parts by mass of polypropylene resin (A), the components (B) and (C) are blended in a total amount of 0.01 to 2.0 parts by mass.

5. The polypropylene resin composition according to Claim 3 or 4, wherein the mass ratio of the total of the component (B) to the component (C) is [(B) / (C)] = 80 / 20 to 1 / 99.

6. A molded article for automobile interior parts formed by molding the polypropylene resin composition according to any one of Claims 1 to 5.

7. The following chemical formula (2): 【Chemical 2】 (In the formula, R1 represents a hydrocarbon group derived from an aliphatic amine containing 3 to 20% by mass of an aliphatic amine having 10 or less carbon atoms, 20 to 70% by mass of an aliphatic amine having 12 carbon atoms, 10 to 30% by mass of an aliphatic amine having 14 carbon atoms, and 5 to 30% by mass of an aliphatic amine having 16 or more carbon atoms in the total aliphatic amine. R2 represents an alkyl group having 1 to 3 carbon atoms. m and n represent the average number of moles of oxyethylene groups added, and are each independently a number of 0.5 or more and 10 or less. R3 represents an alkyl group having 1 to 3 carbon atoms.) An antistatic agent for automobile interior materials containing the quaternary ammonium salt (B) represented by the formula.

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