Glass fiber reinforced propylene resin composition

Abstract

[Problem] To provide a material suitable for producing a glass fiber-reinforced molded body in which the occurrence of white haze is suppressed and the usage quantity of a dispersing agent is low. [Solution] Provided is a glass fiber-reinforced propylene-based resin composition that contains: 10-50 parts by mass of glass fibers and 50-90 parts by mass of a propylene-based resin (the total amount of these two components is 100 parts by mass); 0.3 parts by mass or more of carbon black; and a polyolefin wax having an average particle diameter of 1-40 μm at a quantity such that the mass ratio of the polyolefin wax relative to the carbon black is 0.75-1.5.

Description

[Technical field]

[0001] The present invention relates to a glass fiber reinforced propylene resin composition. [Background technology]

[0002] Fiber-reinforced resin moldings are lightweight and have excellent rigidity and heat resistance, and therefore are used in a wide variety of fields, such as electrical equipment, automobiles, housing equipment, and medical instruments. Known examples of fiber-reinforced resin molded articles include molded articles using reinforcing fibers such as glass fibers and thermoplastic resins such as polyamide and polypropylene. Such fiber-reinforced resin molded articles are used in the automotive field for components that require high rigidity and heat resistance, such as fan shrouds and propeller fans in engine compartments.

[0003] For example, Patent Document 1 describes a vehicle exterior part formed from a long glass fiber reinforced polyolefin composition containing long glass fiber reinforced polyolefin resin pellets, a polyolefin resin, an antioxidant, a light stabilizer, and an ultraviolet absorber, and describes that carbon black, wax, etc. can be further added to this composition. Patent Document 2 describes a long glass fiber reinforced polyolefin composition containing long glass fiber reinforced polyolefin resin pellets, a polyolefin resin, and a pigment having zinc sulfide, and describes that carbon black, wax, etc. can be further added to this composition.

[0004] Patent Document 3 describes a colorant composition containing an olefin resin, carbon black, and glass fiber, and also describes that a polyethylene wax can be further added to this composition as a dispersant and a lubricant.

[0005] Patent Document 4 describes a composite material including a polymer resin and glass fiber strands including glass fibers coated with an aqueous sizing composition disposed in the polymer resin, and describes that the sizing composition may include carbon black, polypropylene wax, and the like.

[0006] On the other hand, Patent Document 5 describes a long-fiber-reinforced propylene-based resin composition containing an ethylene-based polymer having a density, melting point, and heat of fusion within a specified range, and describes that this composition can form a molded article that is suppressed from causing poor appearance such as a white haze on the surface of the molded article (hereinafter also referred to as "occurrence of white haze") and has excellent mechanical properties. [Prior art documents] [Patent documents]

[0007] [Patent Document 1] Japanese Patent Application Publication No. 9-207233 [Patent Document 2] Japanese Patent Application Publication No. 9-183869 [Patent Document 3] JP 2002-53711 A [Patent Document 4] Special Publication No. 2014-512323 [Patent Document 5] International Publication No. 2020 / 091051 Summary of the Invention [Problem to be solved by the invention]

[0008] Molded articles obtained from conventional glass fiber reinforced propylene-based resin compositions have room for further improvement in terms of suppressing the occurrence of haze. The present inventors have found that the white haze can be improved by blending carbon black into a glass fiber reinforced propylene resin composition and further using a metal soap as a dispersant for the carbon black. However, there is room for further improvement in terms of reducing the amount of dispersant used.

[0009] Therefore, an object of the present invention is to provide a material suitable for producing a glass fiber reinforced molding in which the generation of haze is suppressed while the amount of dispersant used is reduced. [Means for solving the problem]

[0010] The gist of the present invention is as follows. [1] 10 to 50 parts by mass of glass fiber, 50 to 90 parts by mass of propylene-based resin (wherein the total of the glass fiber and the propylene-based resin is 100 parts by mass), 0.3 parts by weight or more of carbon black, and The carbon black contains a polyolefin wax having an average particle size of 1 to 40 μm in an amount such that the mass ratio of the polyolefin wax to the carbon black is 0.75 to 1.5. Glass fiber reinforced propylene resin composition.

[0011] [2] The glass fiber reinforced propylene resin composition according to [1], wherein the polyolefin wax is a polypropylene wax.

[0012] [3] The glass fiber reinforced propylene resin composition according to [1] or [2], wherein the carbon black content is 2 parts by mass or less.

[0013] [4] The glass fiber-reinforced propylene-based resin composition according to any one of [1] to [3] above, wherein the propylene-based resin contains a modified polypropylene.

[0014] [5] A method for producing an injection-molded article made of the glass fiber-reinforced propylene-based resin composition according to any one of [1] to [4] above, producing pellets from a part or all of the propylene-based resin and the glass fibers; A step of dry-blending the pellets obtained in the above step, the carbon black, the polyolefin wax, and optionally a portion of the propylene-based resin to obtain a composition; and injection molding the composition A method for producing an injection molded article comprising the steps of: Effect of the Invention

[0015] By using the glass fiber reinforced propylene resin composition of the present invention, it is possible to produce a glass fiber reinforced molding in which the generation of haze is suppressed while reducing the amount of dispersant used. [Brief description of the drawings]

[0016] [Figure 1] FIG. 2 is a schematic diagram of a pellet manufacturing apparatus. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0017] The present invention will now be described in further detail. [Glass fiber reinforced propylene resin composition] The glass fiber reinforced propylene resin composition according to the present invention is characterized by containing glass fibers, a propylene resin, carbon black, and a specified polyolefin wax.

[0018] Glass fiber The glass fiber reinforced propylene resin composition of the present invention contains glass fibers. Examples of glass fibers include filament-like fibers obtained by melt spinning glasses such as E glass (electrical glass), C glass (chemical glass), A glass (alkaline glass), S glass (high strength glass) and alkali-resistant glass.

[0019] In the present invention, glass fibers are usually used as the glass fibers. Continuous glass fiber bundles are usually used as the raw material for the glass fibers, and are commercially available as glass rovings. The average fiber diameter is usually 3 to 30 μm, preferably 13 to 20 μm, and more preferably 16 to 18 μm, and the number of filaments in the bundle is usually 400 to 10,000, preferably 1,000 to 6,000, and more preferably 3,000 to 5,000.

[0020] Also, as described in JP-A-6-114830, a plurality of fiber bundles may be bundled together and used. The surface of the glass fiber may be introduced with functional groups by various surface treatment methods such as electrolytic treatment or sizing agent treatment. For the surface treatment, it is preferable to use a sizing agent, and it is particularly preferable to use a sizing agent containing a coupling agent. When the surface-treated glass fiber is used, the adhesion between the glass fiber and the resin component is improved, and a molded product having good strength and appearance can be obtained.

[0021] Examples of the sizing agent include those containing a coupling agent as described in JP-A-2003-253563. Examples of the coupling agent include silane-based coupling agents such as aminosilane and epoxysilane, and titanium-based coupling agents.

[0022] In addition to the coupling agent, the binder preferably contains a resin emulsion for ease of handling. Examples of the resin emulsion contained in the sizing agent include urethane-based, olefin-based, acrylic-based, nylon-based, butadiene-based, and epoxy-based emulsions, and among these, urethane-based and olefin-based emulsions are preferred.

[0023] Propylene-based resin The glass fiber reinforced propylene-based resin composition of the present invention contains a propylene-based resin. The propylene-based resin is a polymer containing propylene-derived structural units as the main structural units, and examples thereof include propylene homopolymers, propylene-α-olefin random copolymers, and propylene-based block copolymers (hereinafter, these are collectively referred to as "unmodified propylene-based resins"), as well as modified polypropylenes.

[0024] The propylene-α-olefin random copolymer may be a random copolymer of propylene and at least one olefin selected from an α-olefin having 2 carbon atoms (i.e., ethylene) and an α-olefin having 4 to 8 carbon atoms. Examples of the α-olefin include ethylene, 1-butene, 1-pentene, 1-hexene, 4-methyl-1-pentene, 3-methyl-1-pentene, 1-heptene, and 1-octene, preferably ethylene and 1-butene, and particularly preferably ethylene. The proportion of propylene-derived structural units in all structural units in the random copolymer is preferably 90 mol% or more, more preferably 95 mol% or more.

[0025] The propylene-based block copolymer is preferably composed of a propylene homopolymer portion and a propylene-α-olefin random copolymer portion. A specific embodiment of the propylene-α-olefin random copolymer portion is the same as that of the propylene-α-olefin random copolymer.

[0026] When the propylene-based block copolymer is fractionated with an n-decane solvent, it is fractionated into a component soluble in n-decane at 23° C. (hereinafter also referred to as a "decane-soluble portion") and a component insoluble in n-decane at 23° C. (hereinafter also referred to as a "decane-insoluble portion") The content of the decane-soluble portion is usually 5 to 30 mass%, preferably 5 to 25 mass%, and more preferably 8 to 18 mass%, and the content of the decane-insoluble portion is usually 70 to 95 mass%, preferably 75 to 95 mass%, and more preferably 82 to 92 mass%.

[0027] The modified polypropylene is obtained by modifying polypropylene with an acid. The modification method includes a conventionally known method, such as graft modification and copolymerization. The polypropylene to be modified includes the unmodified propylene-based resin.

[0028] The modifier used for modification includes, for example, unsaturated carboxylic acids and their derivatives. 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 include acid anhydrides, esters, amides, imides, and metal salts, and specific examples include maleic anhydride, itaconic anhydride, citraconic anhydride, nadic anhydride, phthalic anhydride, methyl acrylate, methyl methacrylate, ethyl acrylate, butyl acrylate, maleic acid monoethyl ester, acrylamide, maleic acid monoamide, maleimide, N-butylmaleimide, sodium acrylate, and sodium methacrylate. Among these, unsaturated dicarboxylic acids and their derivatives are preferred, and maleic anhydride and phthalic anhydride are more preferred.

[0029] The amount of added acid in the modified polypropylene, in other words, the ratio of the structure derived from the acid in the modified polypropylene, is preferably 0.1 to 14% by weight, more preferably 0.3 to 8% by weight. The amount of added acid is measured by measuring the IR spectrum of the resin and detecting the peak at 1,670 cm -1 ~1,810cm -1 It is determined from the area of ​​the peak.

[0030] In the case where the glass fiber and the propylene-based resin form glass fiber reinforced resin pellets described later, the modification of the polypropylene may be carried out prior to the production of the glass fiber reinforced resin pellets, or may be carried out during the melt-kneading process in the production of the glass fiber reinforced resin pellets.

[0031] If the modified polypropylene contains a modifier or a volatile component derived therefrom (hereinafter, these are also collectively referred to as "volatile components"), the surface of a molded article formed from a glass fiber reinforced propylene-based resin composition may become cloudy. For this reason, it is preferable that the amount of volatile components is small, and the volatile component content in the modified polypropylene defined by the formula described in

[0039] of WO 2020 / 091051 is preferably 9000 ppm or less, more preferably 7000 ppm or less. The amount of volatile components can be reduced by, for example, vacuum drying the modified polypropylene.

[0032] As the modified polypropylene, from the viewpoint of improving the affinity between the glass fiber and the unmodified propylene polymer and enhancing the strength or heat resistance of the produced molded article, fatty acid anhydride-modified polypropylene is preferred, and maleic anhydride-modified polypropylene is particularly preferred.

[0033] The melt flow rate of the modified polypropylene (based on ISO 1133-1, 230°C, 2.16 kg load) is preferably 50 g / 10 min or more, more preferably 80 g / 10 min or more, and the upper limit may be, for example, 1000 g / 10 min. When the melt flow rate of the modified polypropylene is within this range, the glass fiber reinforced propylene resin composition of the present invention has flowability suitable for injection molding.

[0034] The melt flow rate of the propylene-based resin as a whole (based on ISO 1133-1, 230°C, 2.16 kg load) is preferably 25 to 500 g / 10 min, more preferably 50 to 400 g / 10 min, from the viewpoint of injection molding a molded product having excellent mechanical properties with good processability.

[0035] (Glass fiber reinforced resin pellets) In the glass fiber reinforced propylene-based resin composition of the present invention, a part or all of the propylene-based resin (hereinafter also referred to as "propylene-based resin (P1)") and the glass fibers may be in the form of pellets (hereinafter also referred to as "glass fiber reinforced resin pellets").

[0036] The unmodified propylene-based resin (P1) contained in the pellets has a melt flow rate (according to ISO 1133-1, 230°C, 2.16 kg load) of preferably 20 g / 10 min or more, more preferably 30 g / 10 min or more, and even more preferably 40 g / 10 min or more, and the upper limit may be, for example, 300 g / 10 min. When the melt flow rate is in this range, the composition of the present invention has a flowability suitable for injection molding.

[0037] The fiber length of the glass fibers in the glass fiber reinforced resin pellets is usually 4 to 10 mm, preferably 5 to 8 mm, and the fiber diameter is usually 10 to 20 μm, preferably 13 to 18 μm.

[0038] In a glass fiber reinforced resin pellet, the glass fibers are arranged approximately parallel to the longitudinal direction of the pellet, and the fiber length of the glass fibers is usually substantially the same as the particle length of the pellet (i.e., the length of the pellet in the longitudinal direction).

[0039] The content of glass fiber in the glass fiber reinforced resin pellets is preferably 40 to 70 mass%, more preferably 45 to 60 mass%, based on 100 mass% of the glass fiber reinforced resin pellets. When the content of glass fiber is equal to or more than the lower limit, the glass fiber reinforced resin pellets can be produced with good productivity. When the content of glass fiber is equal to or less than the upper limit, the fiber bundles of the glass fiber can be sufficiently impregnated with the resin.

[0040] The amount of modified polypropylene in the glass fiber reinforced resin pellets is preferably 1 to 5 mass %, more preferably 1.5 to 3.5 mass %, based on 100 mass % of the glass fiber reinforced resin pellets. When the amount of modified polypropylene is equal to or more than the lower limit, the adhesion between the glass fiber and the resin component is good. When the amount of modified polypropylene is equal to or less than the upper limit, the molecular weight of the modified polypropylene does not become too low, and therefore the strength of the molded article produced from the composition of the present invention is good.

[0041] The glass fiber reinforced resin pellets usually have a columnar shape. The particle length (length in the longitudinal direction) of the glass fiber reinforced resin pellets is usually 4 to 10 mm, and preferably 5 to 8 mm. When the particle length of the glass fiber reinforced resin pellets is equal to or greater than the lower limit, the molded article produced from the glass fiber reinforced propylene-based resin composition of the present invention has excellent mechanical properties. When the particle length of the glass fiber reinforced resin pellets is equal to or less than the upper limit, the glass fiber reinforced propylene-based resin composition of the present invention has excellent moldability.

[0042] In a glass fiber reinforced resin pellet, the glass fibers are usually aligned approximately parallel to the longitudinal direction of the pellet. Since the aspect ratio of the glass fibers in the glass fiber reinforced resin pellets is large, a molded article formed from the glass fiber reinforced propylene resin composition of the present invention containing the glass fiber reinforced resin pellets has excellent mechanical strength.

[0043] The glass fiber reinforced resin pellets can be produced by a known molding method such as a drawing method. Specifically, the glass fiber reinforced resin pellets can be easily obtained by introducing a roving of several thousand glass fibers into an impregnation die, uniformly impregnating the filaments with molten propylene-based resin (hereinafter also simply referred to as "molten resin"), and then cutting the pellets to the required length.

[0044] In this method, for example, a molten resin is supplied from the extruder into an impregnation die provided at the tip of the extruder, while a continuous glass fiber bundle is passed through the extruder. The glass fiber bundle is then impregnated with the molten resin, and is then drawn through a nozzle and pelletized to a required length.

[0045] Alternatively, an unmodified propylene polymer, an unsaturated carboxylic acid or anhydride thereof may be dry-blended with an organic peroxide and then charged into a hopper of an extruder, thereby simultaneously carrying out modification.

[0046] The method for impregnating the glass fiber roving with the molten resin is not particularly limited, and examples thereof include the method described in

[0036] of International Publication WO 2010 / 137305.

[0047] In the process of melting the resin, an extruder having two or more feed sections may be used, the resin and the decomposing agent may be fed from the top feed, and another resin may be fed from the side feed. As the decomposing agent, an organic peroxide is preferable. Also, two or more extruders (extrusion sections) may be used, and the decomposing agent may be fed into at least one of them. Furthermore, the resin, the unsaturated carboxylic acid or its derivative, and the decomposing agent may be fed into at least one portion of the extruder.

[0048] (Propylene-based resin that may be added separately from glass fiber reinforced resin pellets) When the propylene-based resin (P1) contained in the glass fiber reinforced resin pellets is a part of the propylene-based resin, the glass fiber reinforced propylene-based resin composition of the present invention contains the remaining propylene-based resin (hereinafter also referred to as "propylene-based resin (P2)") in addition to the propylene-based resin (P1).

[0049] The propylene-based resin (P2) is a polymer containing a structural unit derived from propylene as a main structural unit, and examples thereof include a propylene homopolymer, a propylene-α-olefin random copolymer, and a propylene-based block copolymer.

[0050] The details of the propylene-α-olefin random copolymer and the propylene-based block copolymer are as described above. The melt flow rate of the propylene-based resin (P2) (based on ISO 1133-1, 230°C, 2.16 kg load) is preferably 10 to 300 g / 10 min, more preferably 20 to 250 g / 10 min, and even more preferably 20 to 200 g / 10 min. When the melt flow rate of the propylene-based resin (P2) is within this range, the molded article formed from the glass fiber reinforced propylene-based resin composition of the present invention has excellent mechanical properties.

[0051] Examples of the form of the propylene-based resin (P2) include powder and pellets. Carbon Black The glass fiber reinforced propylene resin composition of the present invention contains carbon black.

[0052] The carbon black content in the composition of the present invention is 0.3 parts by mass or more, preferably 0.3 to 2 parts by mass, based on 100 parts by mass of the glass fiber and the propylene-based resin in total. When the carbon black content is within the above range, the generation of white haze is suppressed in the reinforced fiber molding produced from the glass fiber reinforced propylene-based resin composition. On the other hand, when the content is less than 0.3 parts by mass, the generation of white haze may not be suppressed. Also, when the content is equal to or less than the upper limit, the interfacial adhesion between the glass reinforced fiber and the propylene-based resin is good.

[0053] Examples of carbon black include furnace black, acetylene black, thermal black, and channel black. <Polyolefin wax> The glass fiber reinforced propylene resin composition of the present invention contains a polyolefin wax having an average particle size of 1 to 40 μm, preferably 5 to 20 μm. This average particle size is determined by the D 50 It is.

[0054] When the average particle size of the polyolefin wax is within this range, the polyolefin wax can be effectively arranged between the carbon black particles to prevent the carbon black particles from agglomerating, and the dispersibility of the carbon black in the resin component can be improved, thereby suppressing the generation of white haze in the molded product. On the other hand, if the average particle size is smaller than the lower limit, it may be difficult to manufacture the polyolefin wax, and if the average particle size is larger than the upper limit, the dispersibility of the carbon black may decrease, and the generation of white haze in the molded product may not be suppressed.

[0055] In the technology for suppressing the generation of white haze in molded articles made of glass fiber reinforced propylene-based resin compositions by blending with an ethylene-based polymer, there is a tendency for the mechanical properties of the molded articles to decrease as the amount of ethylene-based polymer increases. However, according to the present invention, the generation of white haze is suppressed by blending with carbon black and polyolefin wax, so that it is expected that there will be no concerns when blending with the above-mentioned ethylene-based polymer.

[0056] The polyolefin wax preferably has a polystyrene-equivalent number average molecular weight (Mn) of 2,000 to 10,000, more preferably 3,000 to 4,000, as measured by gel permeation chromatography (GPC) under the following conditions or equivalent conditions.

[0057] Apparatus: Gel permeation chromatograph Alliance GPC2000 (Waters) Solvent: o-dichlorobenzene Columns: 2 TSKgel GMH6-HT and 2 TSKgel GMH6-HTL columns (both manufactured by Tosoh Corporation) Flow rate: 1.0ml / min Sample: 0.15mg / mL o-dichlorobenzene solution Temperature: 140℃ The mass ratio of the polyolefin wax to the carbon black (mass of the polyolefin wax / mass of the carbon black) is 0.75 to 1.5, preferably 0.80 to 1.0. When the mass ratio is within this range, the polyolefin wax is effectively disposed between the carbon black particles to prevent the carbon black particles from agglomerating together, and the dispersibility of the carbon black in the resin component can be improved, thereby suppressing the generation of white haze in the molded product. On the other hand, when the mass ratio is too small compared to the lower limit, the dispersibility of the carbon black is low, and the generation of white haze in the molded product may not be suppressed.

[0058] As the polyolefin wax, polyethylene wax and polypropylene wax are preferred, and polypropylene wax is more preferred. The polyolefin wax may be used alone or in combination of two or more kinds.

[0059] Other Ingredients The glass fiber reinforced propylene resin composition of the present invention may contain a polymer other than the above-mentioned components as necessary, as long as the effect of the present invention is not impaired. Examples of such polymers include ethylene polymers, and examples of ethylene polymers are described in paragraphs

[0054] to

[0055] of International Publication No. WO 2020 / 091051.

[0060] Examples of the ethylene polymers include those described in

[0060] In addition to the above-mentioned components, the glass fiber reinforced propylene resin composition of the present invention may contain additives such as heat stabilizers, antistatic agents, weathering stabilizers, light resistance stabilizers, antiaging agents, antioxidants, copper inhibitors, fatty acid metal salts, softeners, dispersants (excluding the polyolefin wax), fillers, colorants, pigments, and foaming agents, as necessary, within the range that does not impair the effects of the present invention (for example, at a ratio of 5% by mass or less relative to 100% by mass of the composition). These components may be made into master batches.

[0061] (Glass fiber reinforced propylene resin composition) The glass fiber reinforced propylene resin composition of the present invention comprises: 10 to 50 parts by mass, preferably 15 to 45 parts by mass, more preferably 20 to 40 parts by mass of the glass fiber; 50 to 90 parts by mass, preferably 55 to 85 parts by mass, and more preferably 60 to 80 parts by mass of the propylene-based resin (wherein the total of the glass fiber and the propylene-based resin is 100 parts by mass); 0.3 parts by mass or more, preferably 0.3 to 2 parts by mass, of the carbon black; and The polyolefin wax is added in an amount such that the mass ratio of the polyolefin wax to the carbon black is 0.75 to 1.5, preferably 0.80 to 1.0. Contains.

[0062] When the content of each component is within the above range, a molded product in which the generation of white haze is suppressed can be produced. (Method for producing glass fiber reinforced propylene resin composition) The glass fiber reinforced propylene-based resin composition of the present invention can be produced by mixing, for example, dry blending, the glass fiber, the propylene-based resin, the carbon black, the polyolefin wax, and optionally the additives.

[0063] A part or the whole of the propylene-based resin and the glass fibers are preferably mixed in the form of the above-mentioned glass fiber reinforced resin pellets. [Glass fiber reinforced molding] The glass fiber reinforced molding according to the present invention comprises a composition containing the glass fibers, the propylene-based resin, the carbon black, the polyolefin wax, and optionally the additives.

[0064] The details of each component are as described above unless otherwise specified. In addition, the content and technical significance of each component in the composition are the same as the content and technical significance of each component in the glass fiber reinforced propylene resin composition according to the present invention described above unless otherwise specified.

[0065] The length of the glass fibers in the molded product of the present invention is usually different from the length of the glass fibers in the glass fiber-reinforced propylene-based resin composition of the present invention. This is because the glass fibers are broken and shortened during molding. The length of the glass fibers in the glass fiber-reinforced molded product of the present invention is usually 0.5 to 5 mm, preferably 0.8 to 3 mm, expressed as a weight average fiber length calculated based on the following formula by extracting a predetermined number (1000 pieces) of glass fibers from the molded product and measuring the length of each of the fibers.

[0066] Weight average fiber length = Σ(fiber length) 2 / Σ fiber length The glass fiber reinforced molding according to the present invention can be produced by molding a resin composition containing the glass fiber, the propylene-based resin, the carbon black, the polyolefin wax, and optionally the additives, for example, the above-mentioned glass fiber reinforced propylene-based resin composition according to the present invention.

[0067] As the molding method, known molding methods such as injection molding, extrusion molding, blow molding, compression molding, injection compression molding, gas injection molding, or foam injection molding can be applied without any particular restrictions, and among these, injection molding, compression molding, and injection compression molding are particularly preferred, and from the viewpoint of producing a molded body with excellent appearance (i.e., with suppressed generation of haze), injection molding is preferred.

[0068] The molded article of the present invention can be suitably used in various fields such as automobile interior and exterior parts, home appliance parts, etc. An example of an automobile interior and exterior part is an inner material for a back door. EXAMPLES

[0069] The present invention will be described in more detail below with reference to examples, but the present invention is not limited to these examples. (Measurement method) The methods for measuring or evaluating various physical properties are as follows.

[0070] [Melt flow rate] The melt flow rate of the raw material resin was measured under conditions of 230°C and a load of 2.16 kg in accordance with ISO 1133-1.

[0071] [Average particle size] The average particle size of the dispersant is determined by the volume-based particle size distribution measured by the laser diffraction method. 50 was adopted.

[0072] [Appearance of molded product] The appearance of the molded articles produced in the examples was evaluated according to the following criteria. ○: White haze is almost invisible △: White haze is visible, but it is less visible than × ×: The white haze is clearly visible (Raw materials used) The raw materials used in the examples are as follows.

[0073] Propylene-based resin A commercially available propylene homopolymer with the following properties: (Unmodified propylene resin) PP1 (propylene homopolymer (MFR (230°C, 2.16 kg load) = 200 g / 10 min) PP2 (propylene homopolymer (MFR (230°C, 2.16 kg load) = 30 g / 10 min)) (Modified polypropylene) mPP1 (Adivant, product name: POLYBOND3200 (MFR (230°C, 2.16 kg load) = 200g / 10min)) Glass fiber GF (Aminosilane surface-treated glass roving made of 4,000 glass fibers with a fiber diameter of 17 μm, manufactured by Nippon Electric Glass Co., Ltd., product name: T-431N) Carbon Black Commercially available Dispersants Calcium stearate (commercial product with average particle size of 11 μm) Polypropylene wax (commercial product with average particle size of 267 μm) Micronized polypropylene wax (commercially available product with average particle size of 10 μm) (Production of glass fiber reinforced resin composition) [Production Example 1] Glass fiber reinforced resin pellets were produced using the pellet production apparatus shown in FIG.

[0074] In Fig. 1, 10 is a die, 20 is an extruder that supplies molten resin to the die 10, 30 is a roll of fiber bundle F, 40 is a group of tension rolls that apply a certain tension to the fiber bundle F drawn into the die 10, 50 is a cooling means for cooling the molten resin-impregnated fiber bundle drawn out from the die 10, 60 is a drawing roll for the fiber bundle, and 70 is a pelletizer that cuts the molten resin-impregnated fiber bundle drawn out. In this device, three independent fiber bundles F are simultaneously impregnated with molten resin.

[0075] The specific manufacturing conditions are as follows: Die: Attached to the tip of a 50mm diameter extruder, with four rods arranged in a straight line in the impregnation section Fiber bundle: Glass roving consisting of 4,000 glass fibers with a fiber diameter of 17 μm that have been surface-treated with aminosilane (manufactured by Nippon Electric Glass Co., Ltd., product name: T-431N) Preheat temperature: 200℃ Resin: Propylene polymer PP1 and maleic anhydride modified polypropylene mPP1 mixed in a mass ratio of PP1:mPP1 = 48:2 Melting temperature: 280℃ Rods: 4 pieces, 6mm (diameter) x 3mm (length) Under the above conditions, the fiber bundle was fed into the die while adjusting the amount of fiber bundle with a group of tension rolls and impregnated, then pulled out of the die and cooled, and then glass fiber reinforced resin pellets with a particle length of 8 mm, a reinforcing fiber length of 8 mm, and a reinforcing fiber content of 50 mass% were produced using a pelletizer.

[0076] [Comparative Example 1] A glass fiber reinforced resin composition was prepared by dry blending 60 parts by mass of the glass fiber reinforced resin pellets (hereinafter also referred to as "GFMB") produced in Production Example 1, 40 parts by mass of PP2, 0.2 parts by mass of carbon black, and 0.2 parts by mass of calcium stearate.

[0077] Next, a molded article (color plate) was produced from this glass fiber reinforced resin composition using an injection molding machine under the following conditions, and the appearance of the molded article was evaluated. Mold: 90mm x 50mm x 2mm, with 15μm deep embossing Molding temperature: 240℃ Mold temperature: 45℃ The evaluation results are shown in Table 1.

[0078] [Comparative Example 2] A glass fiber reinforced resin composition and a molded body thereof were produced in the same manner as in Comparative Example 1, except that 0.2 parts by mass of calcium stearate was changed to 0.2 parts by mass of polypropylene wax. The evaluation results are shown in Table 1.

[0079] [Comparative Example 3] A glass fiber reinforced resin composition and a molded body thereof were produced in the same manner as in Comparative Example 1, except that 0.2 parts by mass of calcium stearate was changed to 0.2 parts by mass of micronized polypropylene wax. The evaluation results are shown in Table 1.

[0080] [Comparative Example 4] A glass fiber reinforced resin composition and a molded product thereof were produced in the same manner as in Comparative Example 1, except that the blending amount of carbon black was changed to 0.4 parts by mass and the blending amount of calcium stearate was changed to 0.4 parts by mass. The evaluation results are shown in Table 1.

[0081] [Comparative Example 5] A glass fiber reinforced resin composition and a molded body thereof were produced in the same manner as in Comparative Example 2, except that the blending amount of carbon black was changed to 0.4 parts by mass and the blending amount of polypropylene wax was changed to 0.4 parts by mass. The evaluation results are shown in Table 1.

[0082] [Example 1] A glass fiber reinforced resin composition and a molded product thereof were produced in the same manner as in Comparative Example 1, except that the amount of carbon black was changed to 0.4 parts by mass and 0.2 parts by mass of calcium stearate was changed to 0.4 parts by mass of micronized polypropylene wax. The evaluation results are shown in Table 1.

[0083] [Comparative Example 6] A glass fiber reinforced resin composition and a molded product thereof were produced in the same manner as in Comparative Example 1, except that the blending amount of carbon black was changed to 0.8 parts by mass and the blending amount of calcium stearate was changed to 0.8 parts by mass. The evaluation results are shown in Table 1.

[0084] [Comparative Example 7] A glass fiber reinforced resin composition and a molded body thereof were produced in the same manner as in Comparative Example 2, except that the blending amount of carbon black was changed to 0.8 parts by mass and the blending amount of polypropylene wax was changed to 0.8 parts by mass. The evaluation results are shown in Table 1.

[0085] [Example 2] A glass fiber reinforced resin composition and a molded body thereof were produced in the same manner as in Example 1, except that the blending amount of carbon black was changed to 0.8 parts by mass and the blending amount of micronized polypropylene wax was changed to 0.8 parts by mass. The evaluation results are shown in Table 1.

[0086] [Comparative Example 8] A glass fiber reinforced resin composition and a molded product thereof were produced in the same manner as in Comparative Example 1, except that the blending amount of carbon black was changed to 1.2 parts by mass and the blending amount of calcium stearate was changed to 1.2 parts by mass. The evaluation results are shown in Table 1.

[0087] [Comparative Example 9] A glass fiber reinforced resin composition and a molded body thereof were produced in the same manner as in Comparative Example 2, except that the blending amount of carbon black was changed to 1.2 parts by mass and the blending amount of polypropylene wax was changed to 1.2 parts by mass. The evaluation results are shown in Table 1.

[0088] [Example 3] A glass fiber reinforced resin composition and a molded body thereof were produced in the same manner as in Example 1, except that the blending amount of carbon black was changed to 1.2 parts by mass and the blending amount of micronized polypropylene wax was changed to 1.2 parts by mass. The evaluation results are shown in Table 1.

[0089] [Comparative Example 10] A glass fiber reinforced resin composition and a molded product thereof were produced in the same manner as in Comparative Example 1, except that the blending amount of carbon black was changed to 1.6 parts by mass and the blending amount of calcium stearate was changed to 1.6 parts by mass. The evaluation results are shown in Table 1.

[0090] [Comparative Example 11] A glass fiber reinforced resin composition and a molded body thereof were produced in the same manner as in Comparative Example 2, except that the blending amount of carbon black was changed to 1.6 parts by mass and the blending amount of polypropylene wax was changed to 1.6 parts by mass. The evaluation results are shown in Table 1.

[0091] [Example 4] A glass fiber reinforced resin composition and a molded product thereof were produced in the same manner as in Example 1, except that the blending amount of carbon black was changed to 1.6 parts by mass and the blending amount of micronized polypropylene wax was changed to 1.6 parts by mass. The evaluation results are shown in Table 1.

[0092] [Table 1] [Explanation of symbols]

[0093] 10 Die 20 Extruder 30 Roll of fiber bundle F 40 Tension Roll Group 50 Cooling means 60 Drawer Roll 70 Pelletizer

Claims

1. 10 to 50 parts by mass of glass fiber, 50 to 90 parts by mass of propylene-based resin (wherein the total of the glass fiber and the propylene-based resin is 100 parts by mass), 0.3 parts by weight or more of carbon black, and The carbon black contains a polyolefin wax having an average particle size of 1 to 40 μm in an amount such that the mass ratio of the polyolefin wax to the carbon black is 0.75 to 1.

5. Glass fiber reinforced propylene resin composition.

2. 2. The glass fiber reinforced propylene resin composition according to claim 1, wherein the polyolefin wax is a polypropylene wax.

3. 3. The glass fiber reinforced propylene resin composition according to claim 1, wherein the carbon black content is 2 parts by mass or less.

4. The glass fiber reinforced propylene resin composition according to any one of claims 1 to 3, wherein the propylene resin contains a modified polypropylene.

5. A method for producing an injection molded article made of the glass fiber reinforced propylene-based resin composition according to any one of claims 1 to 4, comprising the steps of: producing pellets from a part or all of the propylene-based resin and the glass fibers; A step of dry-blending the pellets obtained in the above step, the carbon black, the polyolefin wax, and optionally a portion of the propylene-based resin to obtain a composition; and injection molding the composition A method for producing an injection molded article comprising the steps of:

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