Method for producing long glass fiber-reinforced propylene resin composition pellets, and method for producing injection molded article

Abstract

One embodiment of the present invention relates to a method for producing composition pellets, which comprises: filling an impregnation mold with a molten mixture obtained by melt-mixing a propylene resin (A), a modified propylene resin (B), a polypropylene wax (C) that can be modified and satisfies specific requirements, and an organic peroxide (D) using a twin-screw extruder; a step in which a bundle of glass long fibers (E) is passed through the impregnation mold and the molten mixture is impregnated into the bundle of glass long fibers (E) to obtain a strand-shaped molded body; and a step in which the strand-shaped molded body is cut to obtain glass long fiber-reinforced propylene resin composition pellets.

Description

Technical Field

[0001] The present invention relates to a method for producing a glass long fiber reinforced propylene resin composition pellet and a method for producing an injection molded body. Background Art

[0002] Fiber-reinforced resin molded bodies are used in various fields such as electrical equipment, automobiles, housing equipment, and medical equipment because of their light weight and excellent rigidity and heat resistance. As fiber-reinforced resin molded bodies, for example, molded bodies using reinforcing fibers such as glass fibers and thermoplastic resins such as polyamide and polypropylene are known. Such fiber-reinforced resin molded bodies are used in the automotive field for components that require high rigidity and heat resistance, such as fan covers and propeller fans in engine compartments.

[0003] A method for producing a coated continuous multi-fiber bundle used as a raw material for a fiber-reinforced resin molding has been proposed, in which a non-volatile compound having a melting point at least 20°C lower than that of a thermoplastic matrix and a viscosity of 2.5 to 100 cS at the application temperature is used as an impregnating agent, preferably a method using polyethylene wax (Patent Document 1).

[0004] Prior art literature

[0005] Patent Literature

[0006] Patent Document 1: Japanese Patent No. 5662156 Summary of the invention

[0007] Problems to be solved by the invention

[0008] Since the affinity between polyethylene wax and polypropylene is poor, the productivity of pellets and the appearance of molded products are not necessarily sufficient.

[0009] An object of the present invention is to provide a method for producing long glass fiber reinforced propylene resin composition pellets and an injection molded article which are highly productive and suitable for obtaining a molded article having a better appearance.

[0010] Technical means to solve problems

[0011] The inventors of the present invention have conducted intensive studies to solve the above-mentioned problems and have found that by using a specific polypropylene wax when manufacturing glass long fiber reinforced propylene resin composition pellets, glass long fiber reinforced propylene resin composition pellets with high productivity and molded bodies with better appearance can be obtained, thereby completing the present invention.

[0012] That is, the present invention relates to, for example, the following [1] to

[12] . [1]

[0014] A method for producing long glass fiber reinforced propylene resin composition pellets, comprising: a step of filling a molten mixture obtained by melt-mixing a propylene resin (A), a modified propylene resin (B), a polypropylene wax (C) which may be modified, and an organic peroxide (D) by a twin-screw extruder into an impregnation mold, passing a bundle of long glass fibers (E) through the impregnation mold, and impregnating the bundle of long glass fibers (E) with the molten mixture to obtain a strand-shaped molded body; and a step of cutting the strand-shaped molded body to obtain long glass fiber reinforced propylene resin composition pellets, wherein the polypropylene wax (C) satisfies the following (I) to (III):

[0015] (I) a melting point (Tm) in the range of 120 to 165° C. as measured by differential scanning calorimetry (DSC);

[0016] (II) Density 890kg / m 3 Above, less than 920kg / m 3 within the scope of

[0017] (III) The number average molecular weight (Mn) measured by gel permeation chromatography (GPC) is in the range of 2,000 to 10,000, and the molecular weight distribution (Mw / Mn) is in the range of 2.0 to 6.0. [2]

[0019] A method for producing glass fiber reinforced propylene resin composition pellets as described in item [1], wherein the melt flow rate (MFR) of the above-mentioned molten mixture measured under the conditions of a measurement temperature of 230°C and a load of 2.16 kg is in the range of 200 to 600 g / 10 minutes. [3]

[0021] The method for producing long glass fiber-reinforced propylene resin composition pellets according to item [1] or [2], wherein the molten mixture is filled into the impregnation mold at a melting temperature in the range of 240 to 320°C. [4]

[0023] The method for producing a glass long fiber reinforced propylene resin composition pellet according to any one of items [1] to [3], wherein the polypropylene wax (C) further satisfies the following (IV):

[0024] (IV) The acid value measured in accordance with JIS K 0070:1992 is 50 mgKOH / g or less. [5]

[0026] The method for producing a glass long fiber reinforced propylene resin composition pellet according to any one of items [1] to [4], wherein the component (A) is used in an amount in the range of 80 to 98 parts by mass, the component (B) is used in an amount in the range of 1 to 10 parts by mass, and the component (C) is used in an amount in the range of 1 to 10 parts by mass [wherein the total of the components (A), (B) and (C) is 100 parts by mass], and the component (D) is used in an amount in the range of 0.001 to 0.5 parts by mass and the component (E) is used in an amount in the range of 50 to 150 parts by mass based on the total of 100 parts by mass of the components (A), (B) and (C). [6]

[0028] The method for producing a glass long fiber reinforced propylene resin composition pellet as described in any one of items [1] to [5], wherein the glass long fiber reinforced propylene resin composition pellet is obtained by cutting a strand-shaped molded body into a length of 5 to 9 mm. [7]

[0030] A method for producing an injection molded article, comprising: a step of obtaining glass long fiber reinforced propylene resin composition pellets by the method for producing glass long fiber reinforced propylene resin composition pellets according to any one of items [1] to [6]; a step of dry-blending 10 to 90 parts by mass of the composition pellets obtained in the above step and 10 to 90 parts by mass of olefin polymer (H) pellets to obtain a mixture [wherein the total amount of the composition pellets and the olefin polymer (H) pellets is set to 100 parts by mass]; and a step of injection molding the above mixture. [8]

[0032] A method for manufacturing an automobile interior and exterior component, comprising the step of obtaining an injection molded body by the manufacturing method described in item [7]. [9]

[0034] A glass long fiber reinforced propylene resin composition pellet, comprising a propylene resin (A), a modified propylene resin (B), a polypropylene wax (C) which may be modified and satisfies the following (I) to (III), and a glass long fiber (E).

[0035] (I) a melting point (Tm) in the range of 120 to 165° C. as measured by differential scanning calorimetry (DSC);

[0036] (II) Density 890kg / m 3 Above, less than 920kg / m 3 within the scope of

[0037] (III) The number average molecular weight (Mn) measured by gel permeation chromatography (GPC) is in the range of 2,000 to 10,000, and the molecular weight distribution (Mw / Mn) is in the range of 2.0 to 6.0.

[10]

[0039] The glass long fiber reinforced propylene resin composition pellets as described in item [9], wherein the polypropylene wax (C) further satisfies the following (IV):

[0040] (IV) The acid value measured in accordance with JIS K 0070:1992 is 50 mgKOH / g or less.

[0041]

[11] The long glass fiber reinforced propylene resin composition pellets as described in item [9] or item

[10] , wherein the long glass fiber reinforced propylene resin composition pellets contain 80 to 98 parts by mass of the component (A), 1 to 10 parts by mass of the component (B), and 1 to 10 parts by mass of the component (C) [wherein the total of the components (A), (B), and (C) is 100 parts by mass], and contain 50 to 150 parts by mass of the component (E) relative to 100 parts by mass of the total of the components (A), (B), and (C).

[12]

[0043] The long glass fiber reinforced propylene resin composition pellets according to any one of items [9] to

[11] , wherein the length of the long glass fiber reinforced propylene resin composition pellets is 5 to 9 mm.

[0044] Effects of the Invention

[0045] The method for producing glass long fiber reinforced propylene resin composition pellets of the present invention has excellent productivity of the composition pellets, and the molded body obtained using the obtained composition pellets has good appearance, for example, good physical properties. Therefore, the composition pellets are suitable as a raw material for molded bodies. DETAILED DESCRIPTION

[0046] The present invention will be described in further detail. Hereinafter, after describing the components used in the method for producing the glass long fiber reinforced propylene resin composition pellets of the present invention (hereinafter sometimes referred to as "the method for producing the pellets of the present invention") and the components used in the method for producing the injection molded article of the present invention, each production method of the present invention will be described. In the following description, the propylene resin (A) is also referred to as "(A) component", and components other than the propylene resin (A) are also marked in the same manner.

[0047] <Acrylic resin (A)>

[0048] The propylene resin (A) as one of the components used in the pellet manufacturing method of the present invention is a polymer containing a structural unit derived from propylene as a main structural unit. Examples of the propylene resin (A) include propylene homopolymers, propylene / α-olefin random copolymers, propylene block copolymers, and other propylene copolymers.

[0049] Examples of propylene copolymers include random copolymers or block copolymers of propylene and at least one α-olefin selected from ethylene and α-olefins having 4 to 20 carbon atoms. The content of the structural unit derived from propylene in the random copolymer is usually 90 to 99 mol%, preferably 92 to 98 mol%. The content of the structural unit derived from propylene in the block copolymer is usually 70 to 99 mol%, preferably 75 to 98 mol%. The content of each structural unit is measured by nuclear magnetic resonance spectroscopy (NMR).

[0050] Specific examples of the α-olefins having 4 to 20 carbon atoms include 1-butene, 2-methyl-1-propylene, 2-methyl-1-butene, 3-methyl-1-butene, 1-pentene, 1-hexene, 2-ethyl-1-butene, 2,3-dimethyl-1-butene, 2-methyl-1-pentene, 3-methyl-1-pentene, 4-methyl-1-pentene, 3,3-dimethyl-1-butene, 1-heptene, 1-methyl-1-pent ... 1-octene, methyl-1-pentene, ethyl-1-hexene, dimethyl-1-hexene, propyl-1-heptene, methylethyl-1-heptene, trimethyl-1-pentene, propyl-1-pentene, diethyl-1-butene, 1-nonene, 1-decene, 1-undecene and 1-dodecene.

[0051] The propylene resin (A) may be a single species or a mixture (composition) of two or more propylene resins (for example, a propylene homopolymer and a propylene copolymer).

[0052] The propylene resin (A) may contain at least one structural unit of a monomer derived from biomass (propylene and α-olefin (including ethylene)). The monomers of the same kind constituting the polymer may be only monomers derived from biomass, only monomers derived from fossil fuels, or both monomers derived from biomass and fossil fuels. Monomers derived from biomass refer to monomers formed from all renewable natural raw materials and their residues, such as plant-derived or animal-derived materials including fungi, yeast, algae, and bacteria, and are expressed as 1×10 -12 The ratio of 14C isotope as carbon is about 100, and the biomass carbon concentration (pMC) measured according to ASTM D 6866 is about 100 (pMC). The monomer derived from biomass can be obtained by, for example, a conventionally known method.

[0053] From the viewpoint of reducing environmental load, it is preferred that the propylene resin (A) contains a structural unit derived from a monomer derived from biomass. When the polymerization catalyst, polymerization temperature and other polymer production conditions are the same, even if the raw material olefin is a propylene polymer containing a biomass-derived olefin, the propylene resin (A) is preferably a monomer derived from biomass. -12 The molecular structure other than containing 14C isotopes in a ratio of about 1:1 is equivalent to that of the propylene polymer (A) containing monomers derived from fossil fuels. Therefore, the performance does not change.

[0054] The propylene resin (A) may also contain at least one structural unit of propylene from chemical recovery. The propylene constituting the polymer may be only propylene from chemical recovery, or may contain propylene from chemical recovery and propylene from fossil fuels and / or propylene from biomass. Propylene from chemical recovery can be obtained by a conventionally known method.

[0055] From the perspective of reducing environmental load (mainly reducing garbage), it is preferred that the propylene resin (A) contains structural units derived from propylene from chemical recycling. Even if the raw material monomer contains monomers from chemical recycling, since the monomers from chemical recycling are monomers obtained by recovering polymers such as waste plastics to monomer units such as propylene through depolymerization, thermal cracking, etc., and monomers manufactured using the monomers as raw materials, as long as the polymer manufacturing conditions such as polymerization catalyst, polymerization process, and polymerization temperature are the same, its molecular structure is also the same as that of propylene homopolymers containing monomers derived from fossil fuels. Therefore, the performance will not change.

[0056] The propylene block copolymer as one example of the propylene resin (A) is preferably composed of a propylene homopolymer part and a propylene / α-olefin random copolymer part. The specific embodiment of the propylene / α-olefin random copolymer part is the same as that of the propylene / α-olefin random copolymer.

[0057] When the propylene block copolymer is separated with a n-decane solvent, it can be separated into a component soluble in n-decane at 23° C. (hereinafter also referred to as a “decane soluble component”) and a component insoluble in n-decane at 23° C. (hereinafter also referred to as a “decane insoluble component”). The content of the decane soluble component is usually 5 to 30% by mass, preferably 5 to 25% by mass, and more preferably 8 to 18% by mass; the content of the decane insoluble component is usually 70 to 95% by mass, preferably 75 to 95% by mass, and more preferably 82 to 92% by mass.

[0058] The melt flow rate (MFR) of the propylene resin (A) measured under the conditions of a measurement temperature of 230°C and a load of 2.16 kg according to ISO 1133-1:2011 is usually in the range of 10 to 110 g / 10 minutes, preferably 20 to 100 g / 10 minutes, and more preferably 30 to 90 g / 10 minutes. When the MFR is within the above range, the injection moldability of the composition of the glass long fiber reinforced propylene resin composition pellets containing the propylene resin (A) is good.

[0059] <Modified acrylic resin (B)>

[0060] The modified propylene resin (B) as one of the components used in the pellet manufacturing method of the present invention is, for example, a modified polymer obtained by modifying the propylene resin (A), preferably an acid-modified polymer obtained by acid-modifying the propylene resin (A). As the modification method of the propylene resin (A), conventionally known methods such as graft modification and copolymerization can be cited. It should be noted that the propylene resin (A) used in the present invention and the propylene resin (A) before modification of the modified propylene resin (B) used in the present invention can be the same resin or different resins.

[0061] As the modifier used for modifying the acrylic resin (A), acid modifiers such as unsaturated carboxylic acids and their derivatives can be cited. Examples of unsaturated carboxylic acids include acrylic acid, methacrylic acid, maleic acid, nadic acid, fumaric acid, itaconic acid, crotonic acid, citraconic acid, sorbic acid, mesaconic acid, angelic acid and phthalic acid. Examples of derivatives of unsaturated carboxylic acids include anhydrides, esters, amides, imides and metal salts. As specific examples, maleic anhydride, itaconic anhydride, citraconic anhydride, nadic anhydride, phthalic anhydride, methyl acrylate, methyl methacrylate, ethyl acrylate, butyl acrylate, monoethyl maleate, acrylamide, maleic acid monoamide, maleimide, N-butylmaleimide, sodium acrylate and sodium methacrylate can be cited. Among them, unsaturated dicarboxylic acids and their derivatives are preferred, and maleic anhydride and phthalic anhydride are more preferred.

[0062] The amount of acid added to the modified propylene resin (B), in other words, the ratio of the structure derived from the acid modifier in the modified propylene resin (B) is preferably 0.1 to 14% by mass, more preferably 0.3 to 8% by mass. The amount of acid added is determined by measuring the IR spectrum of the resin based on 1,670 cm -1 ~1,810cm -1 The peak area was determined.

[0063] As the modified propylene resin (B), from the perspective of improving the affinity between the glass long fiber (E) and the propylene resin (A) and increasing the strength and heat resistance of the manufactured molded body, preferably, it is a propylene resin modified with an unsaturated dicarboxylic acid and / or its derivatives, and particularly preferably, it is a propylene resin modified with maleic anhydride.

[0064] The melt flow rate (MFR) of the modified propylene resin (B) measured under the conditions of a measurement temperature of 230°C and a load of 2.16 kg according to ISO 1133-1:2011 is preferably 50 g / 10 minutes or more, more preferably 80 g / 10 minutes or more, and its upper limit is, for example, 1000 g / 10 minutes, preferably 300 g / 10 minutes, more preferably 250 g / 10 minutes, and further preferably 200 g / 10 minutes. When the MFR of the modified propylene resin (B) is within this range, the composition containing the glass long fiber reinforced propylene resin composition pellets obtained by the production method of the present invention has fluidity suitable for injection molding.

[0065] Furthermore, from the viewpoint of being able to be injection molded into a molded body having excellent mechanical properties with good processability, the melt flow rate of the propylene resin (A) and the modified propylene resin (B) as a whole (according to ISO 1133-1:2011, measurement temperature 230°C, load 2.16 kg) is preferably 25 to 500 g / 10 min, more preferably 50 to 400 g / 10 min.

[0066] The modified propylene-based resin (B) may be a single type or a mixture (composition) of two or more types of modified propylene-based resins.

[0067] <Polypropylene wax (C)>

[0068] The polypropylene wax (C) as one of the components used in the pellet manufacturing method of the present invention satisfies the following (I) to (III). The polypropylene wax (C) may also be modified. Examples of the polypropylene wax (C) include homopolymers of propylene, copolymers of propylene and α-olefins having 2 to 10 carbon atoms other than propylene, and modified polymers obtained by modifying these.

[0069] Specific examples of the α-olefins having 2 to 10 carbon atoms include ethylene and α-olefins having 10 or less carbon atoms among the specific examples of the α-olefins having 4 to 20 carbon atoms.

[0070] (I) The melting point (Tm) measured by differential scanning calorimetry (DSC) is in the range of 120 to 165°C, preferably in the range of 130 to 155°C.

[0071] The polypropylene wax (C) having a melting point (Tm) within the above range has excellent affinity with the propylene resin (A) as a matrix resin, and can provide glass long fiber-reinforced propylene resin composition pellets having excellent productivity and appearance.

[0072] The melting point (Tm) of the polypropylene wax (C) is defined as follows: using DSC, about 5 mg of the sample is kept at 230°C for 10 minutes in a nitrogen environment, the temperature is then lowered to 30°C at a rate of 10°C / min, and after keeping at this temperature for 1 minute, the temperature is increased at a rate of 10°C / min to obtain the peak of the endothermic peak observed on the highest temperature side of the melting endothermic curve.

[0073] (II) Density measured according to JIS K 7112:1999 (A method, 23°C) is 890 kg / m 3 Above, less than 920kg / m 3 , preferably 895~915kg / m 3 In range.

[0074] The polypropylene wax (C) having a density within the above range has excellent affinity with the matrix resin propylene resin (A), and can provide glass long fiber-reinforced propylene resin composition pellets having excellent productivity and appearance.

[0075] (III) The number average molecular weight (Mn) measured by a high temperature GPC (gel permeation chromatography) apparatus is in the range of 2,000 to 10,000, preferably 3,000 to 9,000, more preferably 3,000 to 8,500, and the molecular weight distribution (weight average molecular weight (Mw) / number average molecular weight (Mn)) is in the range of 2.0 to 6.0, preferably 2.2 to 5.8.

[0076] When Mn and Mw / Mn are within the above ranges, glass long fiber-reinforced propylene resin composition pellets having excellent productivity and physical properties can be obtained.

[0077] <Gel Permeation Chromatography (GPC)>

[0078] The measurement was performed by gel permeation chromatography (GPC) using the following apparatus and conditions, and the obtained chromatogram was analyzed by a known method to calculate the Mw value, Mn value and Mw / Mn value.

[0079] (GPC measurement device)

[0080] Liquid chromatograph: HLC-8321GPC / HT manufactured by Tosoh Corporation, Japan

[0081] Detector: RI

[0082] Chromatographic column: TOSOH GMHHR-H(S)HT x 2 made by Tosoh Corporation (measurement conditions)

[0083] Mobile phase: 1,2,4-trichlorobenzene

[0084] Flow rate: 1.0ml / min

[0085] Measurement temperature: 145℃

[0086] Calibration curve drawing method: Use standard polystyrene samples to draw a calibration curve

[0087] Molecular weight conversion: Convert PS (polystyrene) to PP (polypropylene) equivalent molecular weight using universal calibration method

[0088] Sample concentration: 5mg / 10ml

[0089] Sample solution volume: 300 μl

[0090] The polypropylene wax (C) may be an unmodified polypropylene wax, a modified polymer obtained by modifying an unmodified polypropylene wax, or an acid-modified polymer obtained by acid-modifying an unmodified polypropylene wax. As a modification method of the unmodified polypropylene wax, conventionally known methods such as graft modification and copolymerization can be cited.

[0091] As the modifier used for modifying the unmodified polypropylene wax, acid modifiers such as unsaturated carboxylic acids and their derivatives can be cited. These examples are as described above, so the examples are omitted in this section. As the acid modifier, unsaturated dicarboxylic acids and their derivatives are preferred, and maleic anhydride and phthalic anhydride are more preferred. The amount of acid added to the modified polypropylene wax, in other words, the proportion of the structure derived from the acid modifier in the modified polypropylene wax is preferably 0.1 to 14% by mass, more preferably 0.3 to 8% by mass. As the modified polypropylene wax, unsaturated dicarboxylic acids and / or their derivatives modified polypropylene wax are preferred, and maleic anhydride modified polypropylene wax is particularly preferred.

[0092] The polypropylene wax (C) preferably further satisfies the following (IV).

[0093] (IV) The acid value measured in accordance with JIS K 0070: 1992 is 50 mgKOH / g or less, preferably 0 to 30 mgKOH / g, more preferably 0 to 10 mgKOH / g, and further preferably 0 to 1 mgKOH / g. When the acid value is within the above range, a glass long fiber reinforced propylene resin composition pellet having better mechanical properties can be obtained without impairing the adhesion between the propylene resin (A) and the glass long fiber (E).

[0094] The polypropylene wax (C) may be a single type or a mixture (composition) of two or more types of polypropylene waxes.

[0095] <Organic peroxide (D)>

[0096] The organic peroxide (D) as one of the components used in the pellet production method of the present invention is a crosslinking agent, and specific examples thereof include diisopropylbenzene peroxide (DCP), di-tert-butyl peroxide, 2,5-di(tert-butyl peroxide)hexane, 2,5-dimethyl-2,5-di(tert-butyl peroxide)hexane, 2,5-dimethyl-2,5-di(tert-butyl peroxide)-3-hexyne, 1,3-bis(tert-butylperoxyisopropyl)benzene, 1,1-bis(tert-butylperoxy)-3,3,5-trimethylcyclohexane, n-butyl-4,4-bis(tert-butylperoxy)valerate, benzoyl peroxide, p-chlorobenzoyl peroxide, 2,4-dichlorobenzoyl peroxide, tert-butyl perbenzoate, tert-butyl peroxyisopropyl carbonate, diacetyl peroxide, lauroyl peroxide, and tert-butylcumyl peroxide.

[0097] Among them, preferred are dicumyl peroxide (DCP), 2,5-di(tert-butylperoxide)hexane, 2,5-dimethyl-2,5-di(tert-butylperoxide)hexane, 2,5-dimethyl-2,5-di(tert-butylperoxide)-3-hexyne, 1,3-bis(tert-butylperoxyisopropyl)benzene, 1,1-bis(tert-butylperoxide)-3,3,5-trimethylcyclohexane, and 4,4-bis(tert-butylperoxide)valerate.

[0098] The organic peroxide (D) may be used alone or in combination of two or more.

[0099] <Long Glass Fiber (E)>

[0100] The long glass fibers (E) used as one of the components in the pellet manufacturing method of the present invention may be various known long glass fibers, specifically, E glass (Electrical glass), C glass (Chemical glass), A glass (Alkali glass), S glass (High strength glass), alkali-resistant glass, etc., which are products obtained by melt-spinning glass to form filamentary fibers.

[0101] As the glass long fiber (E), glass long fibers are generally used. As the raw material of the glass long fiber, continuous glass long fiber bundles are generally used, and these raw materials are sold on the market as glass rovings. The average fiber diameter is generally 3 to 30 μm, preferably 13 to 20 μm, and more preferably 16 to 18 μm, and the number of filament bundles is generally 400 to 10,000, preferably 1,000 to 6,000, and more preferably 3,000 to 5,000.

[0102] Furthermore, as described in Japanese Patent Application Laid-Open No. 6-114830, a plurality of fiber bundles may be bundled and used.

[0103] The surface of the long glass fiber (E) can be treated with various surface treatment methods such as electrolytic treatment or treatment with a binding agent to introduce functional groups. The surface treatment preferably uses a binding agent, and particularly preferably uses a binding agent containing a coupling agent. If a surface-treated glass fiber is used, the bonding property between the long glass fiber and the resin component can be improved, and a molded body with good strength and appearance can be obtained.

[0104] Examples of the binding agent include coupling agents described in Japanese Patent Application Laid-Open No. 2003-253563. Examples of the coupling agent include silane coupling agents such as aminosilane and epoxysilane, and titanium coupling agents.

[0105] In addition, as a tightening agent, in addition to a coupling agent, it is preferred to contain a resin emulsion for ease of handling. Examples of the resin emulsion contained in the tightening agent include polyurethane-based, olefin-based, acryl-based, nylon-based, butadiene-based or epoxy-based resin emulsions, among which polyurethane-based or olefin-based resin emulsions are preferred.

[0106] The long glass fibers (E) may be used alone or in combination of two or more.

[0107] <Olefin polymer (H)>

[0108] The olefin polymer (H) used in the method for producing the injection molded article of the present invention is a resin polymer such as a homopolymer of α-olefin and a copolymer of two or more α-olefins, for example, homopolymers of ethylene, propylene, 1-butene and 4-methyl-1-pentene, copolymers of two or more α-olefins, specifically ethylene polymers such as high-density polyethylene (HDPE), medium-density polyethylene (MDPE), linear low-density polyethylene (LLDPE) and high-pressure low-density polyethylene (HP-LDPE); propylene polymers such as propylene homopolymers, propylene random copolymers and propylene block polymers; olefin polymers such as poly-1-butene and poly-4-methyl-1-pentene.

[0109] The olefin polymer (H) may be a single type or a mixture (composition) of two or more types of olefin polymers.

[0110] [Method for producing long glass fiber reinforced propylene resin composition pellets]

[0111] The method for producing pellets of a glass long fiber reinforced propylene resin composition of the present invention [the method for producing pellets of the present invention] in one embodiment comprises the steps of filling a molten mixture obtained by melt-mixing the above-mentioned propylene resin (A), the above-mentioned modified propylene resin (B), the above-mentioned polypropylene wax (C) and the above-mentioned organic peroxide (D) by a twin-screw extruder into an impregnation mold, passing the above-mentioned glass long fiber (E) bundle through the middle of the impregnation mold to impregnate the molten mixture into the glass long fiber (E) bundle to obtain a strand-shaped molded body; and cutting the strand-shaped molded body into a length preferably of 5 to 9 mm to obtain pellets of a glass long fiber reinforced propylene resin composition.

[0112] Since the glass long fiber reinforced propylene resin composition pellets obtained by the pellet production method of the present invention contain the modified propylene resin (B), the adhesion between the propylene resin (A) and the glass long fiber (E) bundle is good. By using the polypropylene wax (C), the glass long fiber reinforced propylene resin composition pellets can be produced without sacrificing productivity. The appearance and physical properties (such as mechanical properties such as tensile breaking stress) of the molded body obtained by using the glass long fiber reinforced propylene resin composition pellets obtained by the production method of the present invention are excellent.

[0113] In the production method of the present invention, the MFR of the molten mixture is preferably in the range of 200 to 600 g / 10 minutes, more preferably 280 to 520 g / 10 minutes, further preferably 280 to 450 g / 10 minutes, and particularly preferably 280 to 400 g / 10 minutes. The MFR of the molten mixture is a value measured under the conditions of a measurement temperature of 230° C. and a load of 2.16 kg in accordance with ISO1133-1:2011.

[0114] When the MFR of the molten mixture is within the above range, it is possible to provide glass long fiber reinforced propylene resin composition pellets without impairing the productivity and physical properties of the obtained glass long fiber reinforced propylene resin composition pellets.

[0115] In the method for producing pellets of the present invention, the temperature at which the molten mixture is filled into the impregnation mold is preferably in the range of 240 to 320° C., more preferably 260 to 300° C. When the filling temperature of the molten mixture is within the above range, the molten mixture can be sufficiently impregnated into the long glass fiber (E) bundle.

[0116] In one embodiment of the method for producing pellets of the present invention, the component (A) is preferably used in an amount of 80 to 98 parts by mass, more preferably 91 to 95 parts by mass, the component (B) is preferably used in an amount of 1 to 10 parts by mass, more preferably 3 to 5 parts by mass, and the component (C) is preferably used in an amount of 1 to 10 parts by mass, more preferably 2 to 4 parts by mass. The total of the components (A), (B) and (C) is 100 parts by mass. The component (D) is preferably used in an amount of 0.001 to 0.5 parts by mass, more preferably 0.01 to 0.05 parts by mass, and the component (E) is preferably used in an amount of 50 to 150 parts by mass, more preferably 60 to 140 parts by mass, relative to the total of the components (A), (B) and (C).

[0117] When the amount of component (A) and the like used in the method for producing long glass fiber reinforced propylene resin composition pellets satisfies the above range, the productivity is excellent, and the physical properties of the molded article obtained using the composition are better. That is, long glass fiber reinforced propylene resin composition pellets with a good balance between productivity and physical properties can be produced.

[0118] In the pellet production method of the present invention, in addition to the above-mentioned components, the above-mentioned molten mixture may be mixed with additives such as heat-resistant stabilizers, antistatic agents, weather-resistant stabilizers, light-resistant stabilizers, anti-aging agents, antioxidants, copper damage inhibitors, fatty acid metal salts, softeners, dispersants (excluding the above-mentioned polypropylene wax (C)), fillers, colorants, pigments and foaming agents as needed within a range that does not impair the effects of the present invention (for example, a ratio of 5% by mass or less relative to 100% by mass of the above-mentioned molten mixture). These components may also be made into a masterbatch.

[0119] [Glass long fiber reinforced propylene resin composition pellets]

[0120] The glass long fiber reinforced propylene resin composition pellets of the present invention (hereinafter sometimes referred to as "pellets of the present invention") in a certain embodiment contain a propylene resin (A), a modified propylene resin (B), a polypropylene wax that can be modified (C) and glass long fibers (E).

[0121] The pellets of the present invention may contain an organic peroxide (D) as needed. The pellets of the present invention may contain an additive as needed.

[0122] The details of each component are as described above, and their description is omitted here.

[0123] The pellets of the present invention preferably have a length of 5 to 9 mm. The long glass fibers (E) contained in the pellets of the present invention preferably have a length of 5 to 9 mm.

[0124] In one embodiment, the long glass fibers (E) contained in the pellets are substantially aligned in the length direction of the pellets, and the length of the long glass fibers (E) contained in the pellets is substantially the same as the length of the pellets.

[0125] The pellets of the present invention can be produced, for example, by the above-mentioned method for producing the pellets of the present invention.

[0126] The pellets of the present invention preferably contain 80 to 98 parts by mass, more preferably 91 to 95 parts by mass of the component (A), preferably 1 to 10 parts by mass, more preferably 3 to 5 parts by mass of the component (B), and preferably 1 to 10 parts by mass, more preferably 2 to 4 parts by mass of the component (C). The total of the components (A), (B), and (C) is 100 parts by mass, and the component (E) is preferably contained in the range of 50 to 150 parts by mass, more preferably 60 to 140 parts by mass relative to the total of the components (A), (B), and (C). The pellets of the present invention may contain 0.001 to 0.5 parts by mass, or 0.01 to 0.05 parts by mass of the component (D), relative to the total of the components (A), (B), and (C).

[0127] The glass long fiber reinforced propylene resin composition can be used for the purpose of using the following glass long fiber reinforced propylene resin composition pellets after molding.

[0128] [Application of glass fiber reinforced propylene resin composition pellets]

[0129] The glass fiber reinforced propylene resin composition pellets obtained by the production method of the present invention can be used for automotive parts such as instrument panels, center consoles, rear door modules, rear hoods, front door modules, accelerator pedal modules, airbag housings, air ducts, sunroof structures, battery outer boxes, air filter boxes, shift lever bases, roof longitudinal beams, roof modules, front modules, door pedals, door support modules, handles, armrest cores, muffler covers, hub covers, and other electrical products such as washing machines, washing and drying machines, refrigerators, and vacuum cleaners.

[0130] [Method for producing injection molded article]

[0131] In one embodiment, the method for producing an injection molded article of the present invention comprises the steps of obtaining the above-mentioned glass long fiber reinforced propylene resin composition pellets; dry-blending 10 to 90 parts by mass, preferably 20 to 80 parts by mass, of the composition pellets obtained in the step and 10 to 90 parts by mass, preferably 20 to 80 parts by mass of the above-mentioned olefin polymer (H) pellets [wherein the total of the composition pellets and the olefin polymer (H) pellets is set to 100 parts by mass] to obtain a mixture; and injection molding the mixture.

[0132] The above-mentioned long glass fiber-reinforced propylene resin composition can be obtained by, for example, the above-mentioned pellet production method of the present invention.

[0133] The injection molded article obtained by the method for producing an injection molded article of the present invention can be applied to various fields such as automobile interior and exterior parts (automobile interior and exterior parts, etc.), home appliance parts, etc. An example of an automobile interior and exterior part is a rear door interior material.

[0134] Example

[0135] Hereinafter, the present invention will be described in more detail based on examples, but the present invention is not limited to these examples.

[0136] [Material]

[0137] The propylene resin (A), modified propylene resin (B) and polypropylene wax (C) used in Examples and Comparative Examples are shown below.

[0138] <Acrylic resin (A)>

[0139] As the propylene resin (A), a propylene homopolymer [PP (A-1)] (manufactured by Prime Polymer Co., Ltd., propylene homopolymer, MFR = 60 g / 10 min) was used.

[0140] <Modified acrylic resin (B)>

[0141] As the modified propylene resin (B), a maleic anhydride-modified polypropylene (B-1) (manufactured by Ativant Japan Co., Ltd., trade name "Polybond 3200") having a maleic anhydride grafting amount of 0.5% by mass was used.

[0142] <Polypropylene wax (C)>

[0143] As the polypropylene wax (C) [PPwax (C)], the following polypropylene waxes (C-1) to (C-3) and modified polypropylene wax (C-4) were used. None of the polypropylene waxes (C-1) to (C-3) was modified in any way.

[0144] (1) Polypropylene wax (C-1)

[0145] Trade name: "NP055": manufactured by Mitsui Chemicals, Inc., Tm (first characteristic peak melting point): 136°C, number average molecular weight (Mn): 3320, molecular weight distribution: 2.3, acid value: 0 mgKOH / g, density: 900 kg / m 3 .

[0146] (2) Polypropylene wax (C-2)

[0147] Trade name "NP500": manufactured by Mitsui Chemicals, Inc., Tm (first characteristic peak melting point): 153°C, number average molecular weight (Mn): 5140, molecular weight distribution: 4.0, acid value: 0 mgKOH / g, density: 905 kg / m 3 .

[0148] (3) Polypropylene wax (C-3)

[0149] Trade name: "NP506": manufactured by Mitsui Chemicals, Inc., Tm (first characteristic peak melting point): 128°C, number average molecular weight (Mn): 8150, molecular weight distribution: 3.2, acid value: 0 mgKOH / g, density: 897 kg / m 3 .

[0150] (4) Modified polypropylene wax (C-4)

[0151] Trade name: "NP0555A": manufactured by Mitsui Chemicals, Inc., Tm (first characteristic peak melting point): 129°C, number average molecular weight (Mn): 6150, molecular weight distribution: 3.9, acid value: 45 mgKOH / g, density: 919 kg / m 3 .

[0152] <Other waxes (G)>

[0153] As other waxes (G), the following polyethylene waxes (PE waxes) (G-1), (G-2) and microcrystalline wax (MC wax) (G-3) were used. Polyethylene waxes (G-1) and (G-2) were not modified in any way.

[0154] (1) Polyethylene wax (G-1)

[0155] Trade name "NL900": Made by Mitsui Chemicals Co., Ltd., Tm: 103°C, number average molecular weight (Mn): 3810, molecular weight distribution: 5.1, density: 920kg / m 3 .

[0156] (2) Polyethylene wax (G-2)

[0157] Trade name "NL100": Made by Mitsui Chemicals Co., Ltd., Tm: 116°C, number average molecular weight (Mn): 1380, molecular weight distribution: 3.5, density: 920kg / m 3 .

[0158] (3) Microcrystalline wax (G-3)

[0159] Trade name "Hi-Mic 1080": manufactured by Nippon Seiro Co., Ltd., Tm: microcrystalline wax with a melting point of 84°C.

[0160] The organic peroxide (D), long glass fibers (E) and antioxidant (F) used in the examples and comparative examples are shown below.

[0161] (1) Organic peroxide (D)

[0162] As the organic peroxide (D-1), 1,3-bis(tert-butylperoxyisopropyl)benzene: trade name “Perkadox 14”: manufactured by Kayaku Akzo Corporation was used.

[0163] (2) Long glass fiber (E)

[0164] As the glass long fibers (E-1), glass fiber rovings having a glass fiber diameter of 17 μm and 2400 tex manufactured by Nippon Electric Glass Co., Ltd. were used.

[0165] (3) Antioxidant (F)

[0166] As the antioxidant, the following two antioxidants were used.

[0167] (F-1) Trade name “Irg1010”: phenolic antioxidant Irganox (registered trademark) 1010 manufactured by BASF.

[0168] (F-2) Trade name “Irg168”: phosphorus antioxidant, Irganox (registered trademark) 168 manufactured by BASF.

[0169] [Examples 1 to 6, Comparative Examples 1 to 5]

[0170] As the components (A), (B), (C), (D), (F) and (G), the components shown in Table 1 were used, and were uniformly mixed with a drum mixer. The mixture was supplied to a co-rotating twin-screw kneader (KTX30 (registered trademark) manufactured by Kobe Steel Co., Ltd.), and the molten mixture was filled into an impregnation mold at the resin temperature described in Table 1 (the melting temperature was 260° C. in the case of Example 1, for example). Next, a glass long fiber roving (component (E-1)) was added to the impregnation mold, and after impregnation with the molten mixture, it was pulled up into a strand, and cut with a pelletizer to obtain glass long fiber reinforced propylene resin composition pellets with a length of about 8 mm. The pulling speed of the strand was determined by checking the breakage of the glass long fiber at the outlet of the impregnation mold, and the pulling speed was increased to a speed at which the strand was not broken, and the maximum speed was taken as the pulling speed (production speed).

[0171] [Measurement method and evaluation method]

[0172] The measurement methods related to the compositions used in Examples and Comparative Examples and the evaluation methods of the molded products are as follows.

[0173] <MFR of [(A)+(B)+(C)+(D) components] of molten mixture>

[0174] A mixture of components (A) + (B) + (C) + (D) (in the comparative example, a mixture of components (A) + (B) + (D) or a mixture of components (A) + (B) + (G) + (D)) was supplied to a co-rotating twin-screw kneader (KTX30 (registered trademark) manufactured by Kobe Steel, Ltd.), and after filling the impregnation mold, the mixture was extracted from the impregnation mold, and the MFR was measured under the conditions of a measurement temperature of 230°C and a load of 2.16 kg.

[0175] <Unopened Glass Fiber (Appearance)>

[0176] Using the glass long fiber reinforced propylene resin composition pellets obtained in the examples and comparative examples, 30 injection-molded sheets with a size of 80 mm × 240 mm × 3 mm were produced using an injection molding machine at a barrel temperature of 240° C. and a mold temperature of 40° C. The number of white spots derived from the unopened glass fibers in the 30 injection-molded sheets was counted as the number of unopened glass fibers.

[0177] <Tensile Breaking Stress>

[0178] The glass long fiber reinforced propylene resin composition pellets obtained in the examples and comparative examples were molded into ISO No. 1 dumbbells using an injection molding machine at a barrel temperature of 240° C. and a mold temperature of 40° C. A tensile fracture test was performed using the obtained ISO No. 1 dumbbells at a tensile speed of 5 mm / min in accordance with ISO527.

[0179] The results are shown in Table 1.

[0180] [Table 1]

[0181]

[0182] As shown in Table 1, in Examples 1 to 4, by adding the polypropylene wax (C), glass long fiber reinforced propylene resin composition pellets can be produced without reducing the production speed, and the molded bodies obtained using the pellets have excellent appearance and tensile breaking stress.

[0183] The glass long fiber-reinforced propylene resin composition pellets of Example 6 in which the blending amount of the polypropylene wax (C) was 10 parts by mass had higher productivity, but the tensile breaking stress of the molded article obtained using the composition was reduced.

[0184] On the other hand, although the method without adding polypropylene wax (C) reduces the production speed of glass long fiber reinforced propylene resin composition pellets, the molded body obtained using the obtained composition pellets (Comparative Example 1) has no problems in appearance and tensile fracture stress. It should be noted that in Comparative Example 2, when the resin temperature in the impregnation mold was set to 220°C, the viscosity of the molten resin increased and glass long fiber reinforced propylene resin composition pellets could not be produced.

[0185] It was confirmed that when polyethylene wax (G) was used instead of polypropylene wax (C) used in Examples 1 to 4 [Comparative Examples 3 and 4], the affinity between the propylene resin (A) and the polyethylene wax (G) of the molded body obtained using the pellets was poor, so the production speed was reduced and the appearance was poor.

[0186] In Example 5 using modified PP wax (C-4), although the tensile breaking stress was lower than that of Examples 1 to 4, probably because the modified PP wax (C-4) affected the adhesion between the propylene resin (A) and the long glass fiber (E), a high production speed was shown. This is believed to be because the modified PP wax exhibited a lubricant-like effect on the long glass fiber, thereby reducing the flow resistance near the nozzle and increasing the production speed.

[0187] In addition, when MC wax was used instead of polypropylene wax (C) (Comparative Example 6), although the production speed of glass long fiber reinforced propylene resin composition pellets was reduced, the molded body obtained using the obtained composition pellets had no problems in appearance and tensile breaking stress.

[0188] Industrial Applicability

[0189] The fiber-reinforced polypropylene resin composition pellets of the present invention can be suitably used as a molding material in various fields such as automotive interior and exterior components such as instrument panels and center consoles, and home appliance parts.

Claims

1. A method for producing a glass long fiber reinforced propylene resin composition pellet, characterized in that: include: A step of filling a molten mixture obtained by melt-mixing a propylene resin (A), a modified propylene resin (B), a polypropylene wax (C) which may be modified, and an organic peroxide (D) by a twin-screw extruder into an impregnation mold, and then passing a bundle of long glass fibers (E) through the impregnation mold to impregnate the bundle of long glass fibers (E) with the molten mixture to obtain a strand-shaped molded body; and The strand-shaped molded body is cut into pellets of a glass fiber reinforced propylene resin composition. The polypropylene wax (C) satisfies the following (I) to (III): (I) a melting point (Tm) in the range of 120 to 165° C. as measured by differential scanning calorimetry (DSC); (II) Density 890kg / m 3 Above, less than 920kg / m 3 within the scope of (III) The number average molecular weight (Mn) measured by gel permeation chromatography (GPC) is in the range of 2,000 to 10,000, and the molecular weight distribution (Mw / Mn) is in the range of 2.0 to 6.

0.

2. The method for producing a glass long fiber reinforced propylene resin composition pellet according to claim 1, characterized in that: The melt mixture has a melt flow rate (MFR) in the range of 200 to 600 g / 10 minutes measured under the conditions of a measurement temperature of 230° C. and a load of 2.16 kg.

3. The method for producing a glass long fiber reinforced propylene resin composition pellet according to claim 1, characterized in that: The molten mixture is filled into the impregnation mold at a melting temperature in the range of 240 to 320°C.

4. The method for producing glass long fiber reinforced propylene resin composition pellets according to claim 1, characterized in that: The polypropylene wax (C) further satisfies the following (IV): (IV) The acid value measured in accordance with JIS K 0070:1992 is 50 mgKOH / g or less.

5. The method for producing a glass long fiber reinforced propylene resin composition pellet according to claim 1, characterized in that: The component (A) is used in an amount of 80 to 98 parts by mass, the component (B) is used in an amount of 1 to 10 parts by mass, and the component (C) is used in an amount of 1 to 10 parts by mass, wherein the total of the components (A), (B) and (C) is 100 parts by mass. The component (D) is used in an amount of 0.001 to 0.5 parts by mass and the component (E) is used in an amount of 50 to 150 parts by mass based on 100 parts by mass of the total of the components (A), (B) and (C).

6. The method for producing long glass fiber reinforced propylene resin composition pellets according to claim 1, characterized in that: The strand-shaped molded body is cut into pieces having a length of 5 to 9 mm to obtain the glass long fiber-reinforced propylene resin composition pellets.

7. A method for producing an injection molded body, characterized in that: include: A step of obtaining glass long fiber reinforced propylene resin composition pellets by the production method according to any one of claims 1 to 6; A step of dry-blending 10 to 90 parts by mass of the composition pellets obtained in the above step and 10 to 90 parts by mass of the olefin polymer (H) pellets to obtain a mixture, wherein the total of the composition pellets and the olefin polymer (H) pellets is set to 100 parts by mass; and The mixture is subjected to an injection molding process.

8. A method for manufacturing an automobile interior and exterior decoration component, characterized in that: The method comprises the step of obtaining an injection molded body by the production method according to claim 7.

9. A glass long fiber reinforced propylene resin composition pellet, characterized in that: The invention comprises a propylene resin (A), a modified propylene resin (B), a polypropylene wax (C) which may be modified and satisfies the following (I) to (III), and a long glass fiber (E). (I) a melting point (Tm) in the range of 120 to 165° C. as measured by differential scanning calorimetry (DSC); (II) Density 890kg / m 3 Above, less than 920kg / m 3 within the scope of (III) The number average molecular weight (Mn) measured by gel permeation chromatography (GPC) is in the range of 2,000 to 10,000, and the molecular weight distribution (Mw / Mn) is in the range of 2.0 to 6.

0.

10. The glass long fiber reinforced propylene resin composition pellets according to claim 9, characterized in that: The polypropylene wax (C) further satisfies the following requirement (IV), (IV) The acid value measured in accordance with JIS K 0070:1992 is 50 mgKOH / g or less.

11. The glass long fiber reinforced propylene resin composition pellets according to claim 9 or 10, characterized in that: The glass long fiber reinforced propylene resin composition pellets contain 80 to 98 parts by mass of component (A), 1 to 10 parts by mass of component (B), and 1 to 10 parts by mass of component (C), wherein the total of components (A), (B), and (C) is 100 parts by mass. The component (E) is contained in an amount of 50 to 150 parts by mass based on 100 parts by mass of the total of the components (A), (B), and (C).

12. The glass long fiber reinforced propylene resin composition pellets according to claim 9 or 10, characterized in that: The length of the glass long fiber reinforced propylene resin composition pellets is 5 to 9 mm.

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