JP6891438B2 - Molding material - Google Patents

Description

The present invention relates to a molding material comprising a thermoplastic resin and reinforcing fibers. More specifically, the present invention relates to a molding material having good dispersion of reinforcing fibers in a molded product when injection molding is performed.

A molding material composed of a thermoplastic resin and a reinforcing fiber is lightweight and easy to mold, and does not require a storage load like a thermosetting resin, and has excellent recyclability. It is widely used as a structural member for aircraft, automobiles, ships, electronic device housings, sports applications, and industrial materials such as building materials. In particular, the molding material processed into pellets can be applied to molding methods having excellent economic efficiency and productivity such as injection molding and stamping molding, and is useful as an industrial material.

However, in the process of manufacturing a molding material, impregnating a continuous reinforcing fiber bundle with a thermoplastic resin has problems in terms of economy and productivity. For example, it is well known that the higher the melt viscosity of the resin, the more difficult it is to impregnate the reinforcing fiber bundle. Thermoplastic resins with excellent mechanical properties such as toughness and elongation are particularly high molecular weight bodies, have higher viscosities than thermosetting resins, and require a higher process temperature, which facilitates molding materials. In addition, it was not suitable for highly productive production. On the other hand, when a low molecular weight, that is, a low viscosity thermoplastic resin is used as the matrix resin due to the ease of impregnation, there is a problem that the dispersibility of the fibers of the obtained molded product is significantly lowered.

For example, Patent Document 1 discloses a molding material in which a high molecular weight thermoplastic resin is arranged so as to be in contact with a composite composed of a low molecular weight thermoplastic polymer and continuous reinforcing fibers. In this molding material, a low molecular weight substance is used for impregnation of continuous reinforcing fiber bundles, and a high molecular weight substance is used for the matrix resin, thereby achieving both economic efficiency, productivity and mechanical properties. However, in recent years, as fiber-reinforced composite materials have attracted a great deal of attention and have been used in a wide variety of applications, such molding materials have been required to be improved in various ways.

For example, Patent Documents 2 and 3 disclose a molding material composed of a reinforcing fiber and a propylene-based resin. Molded products obtained by molding these molding materials are inexpensive and lightweight molding materials that take advantage of the characteristics of propylene-based resins, but improvement of mechanical properties is a continuous technical issue when expanding sales to various applications. .. One approach for mechanical properties was to increase the content of reinforcing fibers.

Japanese Unexamined Patent Publication No. 10-138379 JP-A-2010-248483 Japanese Unexamined Patent Publication No. 2003-13831

On the other hand, in the molding material composed of the reinforcing fiber and the propylene resin, when the content of the reinforcing fiber is increased, the dispersibility of the reinforcing fiber in the molded product is inferior, and the concentration of the reinforcing fiber in each part tends to be uneven. On the contrary, the mechanical properties are deteriorated, and the surface of the molded product becomes uneven, resulting in an abnormal appearance. As described above, there is a trade-off relationship between the increase in the content of the reinforcing fibers and the fiber dispersibility during molding, and it is an important technical issue to achieve both of these.

The present invention attempts to improve the problems of the prior art, and by specifying the composition constituting the molding material, it is possible to provide a molded product having sufficiently improved fiber dispersibility in the molded product with high productivity. Is the subject.

In order to solve the above problems, the molding material of the present invention adopts the following constitution. That is, the thermoplastic resin (A) and the resin-adhered reinforcing fiber (D) formed by adhering the compound (B) to the reinforcing fiber (C) are included, and the resin-adhered reinforcing fiber (D) and the thermoplastic resin ( A molding material to which A) is bonded, and the thermoplastic resin (A) is at least one thermoplastic resin selected from the group consisting of polyolefin, polyamide, polyester, polycarbonate, and polyarylene sulfide, and is a compound. (B) is a molding material, which is a petroleum resin.

By using a petroleum resin in the molding material of the present invention, it is possible to achieve a dramatic improvement in the dispersibility of the reinforcing fibers in the obtained molded product. In addition, because of its excellent fiber dispersibility in molding materials, the molded products are excellent in mechanical properties, and can be applied to a wide range of applications such as automobile interior / exterior, electrical / electronic equipment housings, reinforcing materials in the field of civil engineering and construction, and sports equipment. it can. The molding material of the present invention can be suitably used for producing such a molded product with high productivity.

It is a schematic diagram which shows an example of the form of the resin adhesion reinforcing fiber (D) which is formed by adhering compound (B) to reinforcing fiber (C). It is a schematic diagram which shows an example of a preferable embodiment of the molding material of this invention. It is the schematic which shows an example of the shape of the cross section in the axial direction of the preferable aspect of the molding material of this invention. It is the schematic which shows an example of the shape of the cross section in the axial direction of the preferable aspect of the molding material of this invention. It is the schematic which shows an example of the shape of the orthogonal cross section of the preferable aspect of the molding material of this invention. It is the schematic which shows an example of the shape of the orthogonal cross section of the preferable aspect of the molding material of this invention. It is the schematic which shows an example of the shape of the orthogonal cross section of the preferable aspect of the molding material of this invention. It is the schematic which shows an example of the shape of the orthogonal cross section of the preferable aspect of the molding material of this invention. It is the schematic which shows an example of the shape of the orthogonal cross section of the preferable aspect of the molding material of this invention.

The molding material of the present invention is a molding material containing a thermoplastic resin (A) and a resin-attached reinforcing fiber (D) formed by adhering a compound (B) to a reinforcing fiber (C). First, these components will be described.

The thermoplastic resin (A) used in the present invention is at least one thermoplastic resin selected from the group consisting of polyolefin, polyamide, polyester, polycarbonate, and polyarylene sulfide. As the thermoplastic resin (A), polyolefin and polyamide are preferable from the viewpoint of balancing the economic efficiency and mechanical properties of the obtained molded product, and polyolefin is more preferable from the viewpoint of the light weight of the obtained molded product.

The polyolefin is preferably a density 0.8~1.0g / cm ^3, it is more preferred 0.8 to 0.9 g / cm ^3. By setting the density of polyolefin within such a range, a molded product having excellent light weight can be obtained.

Examples of the polyolefin include homopolymers of propylene or copolymers of propylene with at least one α-olefin, conjugated diene, non-conjugated diene and the like.

Examples of the monomer repeating unit constituting α-olefin include ethylene, 1-butene, 3-methyl-1-butene, 4-methyl-1-pentene, 3-methyl-1-pentene, and 4-methyl-. 2-hexene, 4,4-dimethyl-1-hexene, 1-monomer, 1-octene, 1-hexene, 1-hexene, 1-decene, 1-undecene, 1-dodecene, etc. Twelve α-olefins and the like can be mentioned, and the monomer repeating units constituting the conjugated diene and the non-conjugated diene include butadiene, ethylidene norbornene, dicyclopentadiene, 1,5-hexadiene and the like, and other single amounts thereof. One type or two or more types can be selected as the body repetition unit.

Examples of the polyolefin include homopolymers of propylene, random or block copolymers of one or more of the other monomers of propylene and the above-mentioned other monomers, copolymers of other thermoplastic monomers, and the like. be able to. For example, polypropylene, ethylene / propylene copolymer, propylene / 1-butene copolymer, ethylene / propylene / 1-butene copolymer and the like are preferable.

Generally, a homopolymer of propylene is used when rigidity is required, and one or more random or blocked propylenes of propylene and the other monomers are used when impact resistance is required. ..

Further, the polyolefin is preferably a modified polyolefin from the viewpoint of improving the mechanical properties of the obtained molded product. It is preferably an acid-modified polyolefin, which is a polyolefin having a group of a carboxylic acid and / or a salt thereof bonded to a polymer chain. The acid-modified polyolefin can be obtained in a variety of ways, for example, the polyolefin is neutralized, unneutralized, a monomer having a carboxylic acid group, and / or saponified. It can be obtained by graft-polymerizing a monomer having an unneutralized carboxylic acid ester.

Here, examples of the monomer having a carboxylic acid group that has been neutralized or not neutralized and the monomer having a carboxylic acid ester group that has been sanitized or not sanitized include ethylene. Examples thereof include based unsaturated carboxylic acids and anhydrides thereof, and examples thereof include esters thereof and compounds having an unsaturated vinyl group other than olefins.

Examples of the ethylene-based unsaturated carboxylic acid include (meth) acrylic acid, maleic acid, fumaric acid, tetrahydrophthalic acid, itaconic acid, citraconic acid, crotonic acid, isocrotonic acid, and the like. [2,2,1] Examples thereof include hept-5-ene-2,3-dicarboxylic acid, maleic anhydride, and citraconic anhydride.

Examples of monomers having an unsaturated vinyl group other than olefins include methyl (meth) acrylate, ethyl (meth) acrylate, propyl (meth) acrylate, n-butyl (meth) acrylate, i-butyl (meth) acrylate, and tert. -Butyl (meth) acrylate, n-amyl (meth) acrylate, isoamyl (meth) acrylate, n-hexyl (meth) acrylate, 2-ethylhexyl (meth) acrylate, octyl (meth) acrylate, decyl (meth) acrylate, dodecyl (Meta) acrylate, octadecyl (meth) acrylate, stearyl (meth) acrylate, tridecyl (meth) acrylate, lauroyl (meth) acrylate, cyclohexyl (meth) acrylate, benzyl (meth) acrylate, phenyl (meth) acrylate, isobolonyl (meth) ) Acrylate, (meth) acrylic acid esters such as dicyclopentanyl (meth) acrylate, dicyclopentenyl (meth) acrylate, dimethylaminoethyl (meth) acrylate, diethylaminoethyl (meth) acrylate, hydroxyethyl acrylate, 2- Hydroxyl-containing vinyls such as hydroxyethyl (meth) acrylate, 2-hydroxypropyl (meth) acrylate, 4-hydroxybutyl acrylate, lactone-modified hydroxyethyl (meth) acrylate, 2-hydroxy-3-phenoxypropyl acrylate, glycidyl (meth) ) Acrylate, epoxy group-containing vinyls such as methylglycidyl (meth) acrylate, isocyanate group-containing vinyls such as vinyl isocyanate and isopropenyl isocyanate, aromatic vinyls such as vinyltoluene and t-butylstyrene, acrylamide, Amidos such as methacrylicamide, N-methylolmethacrylicamide, N-methylolacrylamide, diacetoneacrylamide, maleic acid amide, vinyl esters such as vinyl acetate and vinyl propionate, N, N-dimethylaminoethyl (meth) acrylate, N, N-diethylaminoethyl (methacrylate, N, N-dimethylaminopropyl (meth) acrylate, N, N-dipropylaminoethyl (meth) acrylate, N, N-dibutylaminoethyl (meth) acrylate, N, N -Aminoalkyl (meth) acrylates such as dihydroxyethylaminoethyl (meth) acrylates Classes, unsaturated sulfonic acids such as styrene sulfonic acid, sodium styrene sulfonic acid, 2-acrylamide-2-methylpropane sulfonic acid, mono (2-methacryloyloxyethyl) acid phosphate, mono (2-acryloyloxyethyl) acid. Examples thereof include unsaturated phosphoric acids such as phosphate.

These monomers can be used alone or in combination of two or more. Among these, acid anhydrides are preferable, and maleic anhydride is more preferable.

From the viewpoint of mechanical properties and economic efficiency of the obtained molded product, it is preferable to use a mixture of modified polyolefin and unmodified polyolefin as the polyolefin. Specifically, it is preferable to have 5% by mass or more and 30% by mass or less of the modified polyolefin and 70% by mass or more and 95% by mass or less of the unmodified polyolefin.

Examples of the polyamide include polymers that form a main chain by repeating amide groups, such as aliphatic polyamides such as nylon 6, nylon 66, nylon 11, nylon 610 and nylon 612, and aromatic polyamides such as nylon 6T. Can be mentioned.

The compound (B) used in the present invention is a petroleum resin. Petroleum resin is a polymer of a hydrocarbon compound produced as a by-product during thermal decomposition of naphtha, and is derived from C9 petroleum resin obtained by polymerizing a C9 distillate composed of aromatic hydrocarbons and aliphatic hydrocarbons. C5 petroleum resin obtained by polymerizing the C5 distillate, and C5-C9 copolymerized petroleum resin obtained by copolymerizing the C9 distillate and the C5 distillate as raw materials, and the petroleum resins thereof are made of maleic anhydride, maleic acid, and the like. Examples thereof include modified petroleum resins modified with fumaric acid, (meth) acrylic acid, phenol and the like.

In order to improve the fiber dispersibility of the reinforcing fiber (C) during injection molding, it is preferable that the compound (B) and the thermoplastic resin (A) have high compatibility and a high melt viscosity maintenance rate during melt kneading. Such compound (B) is a petroleum resin. In the present invention, the petroleum resin is a petroleum-derived resin, and excludes bio-derived or plant-derived resins such as terpene-based resins. For example, in the case of a plant-derived resin that is not a petroleum resin, specifically, in the case of a terpene-based resin, the viscosity is significantly reduced when melt-kneaded with the thermoplastic resin (A), and the fiber dispersibility is higher than that of the petroleum resin. Is insufficient.

Examples of the C9 petroleum resin include polymers of at least one compound selected from the group consisting of inden, methylinden, vinyltoluene, styrene, α-methylstyrene and β-methylstyrene as the C9 distillate, and further vinyl. It is preferably a polymer of at least one selected from toluene, inden and α-methylstyrene, and more preferably a polymer of a mixture of vinyltoluene, inden and α-methylstyrene.

In the present invention, the compound (B) is preferably a resin containing 50% by mass or more of the polymer of the C9 fraction with respect to the compound (B), and more preferably 100% by mass. Under such conditions, the compatibility between the compound (B) and the thermoplastic resin (A) can be enhanced, and the dispersibility of the reinforcing fiber (C) in the molded product can be improved.

As the compound (B) containing 50% by mass or more of a polymer of a mixture of vinyltoluene, indene and α-methylstyrene, Arakawa Chemical Industry Co., Ltd.'s Archon M-135, M-115, M-100, M-90 , P-125, P-115, P-100, P-90 and the like. The components and content of the petroleum resin can be calculated by proton nuclear magnetic resonance spectrum ( ¹ _{H-NMR) as a deuterated chloroform (CDCl 3) solution.}

Examples of the C5 petroleum resin include polymers of aliphatic hydrocarbons such as pentene, pentadiene, and isoprene, which are C5 fractions. Examples of such C5 petroleum resin include Idemitsu Kosan Co., Ltd.'s Imarve S-100 and S-110.

From the viewpoint of compatibility with various thermoplastic resins (A) such as polyolefin and polyamide, C9 petroleum resin is preferable to C5 petroleum resin.

In the present invention, the compound (B) is preferably a resin made of a hydrogenated polymer. In particular, when polyolefin is used as the thermoplastic resin (A), the compatibility with the thermoplastic resin (A) is improved by using the hydrogenated petroleum resin as the compound (B), and it is strengthened during injection molding. The dispersibility of the fiber (C) in the molded product can be improved.

The hydrogenated petroleum resin is obtained by hydrogenating the petroleum resin.
The hydrogenation rate can be controlled by changing the amount of catalyst, hydrogen pressure, and reaction time as conditions for the hydrogenation reaction. The hydrogenation rate is preferably 60% or more, more preferably 80% or more, still more preferably 90% or more of the double bonds contained in the aromatic ring or the like of compound (B). Examples of such petroleum resins having a high hydrogenation rate include Alcon P-125, P-115, P-100, and P-90 of Arakawa Chemical Industry Co., Ltd. as C9 petroleum resins, and C5 petroleum resins. , Idemitsu Kosan Co., Ltd.'s Imarve P-100, P-125, P-140 and the like. The hydrogenation rate of petroleum resin can be calculated from the unit structure of petroleum resin obtained by ¹ H-NMR as a deuterated chloroform (CDCl ₃ ) solution based on the following formula.
Hydrogenation rate = {Number of alicyclic structures produced by hydrogenation of aromatic rings / (Number of aromatic rings + Number of alicyclic structures produced by hydrogenation of aromatic rings)} x 100 (%).

As the reinforcing fiber (C) used in the present invention, for example, high-strength, high-elasticity fibers such as carbon fiber, glass fiber, aramid fiber, alumina fiber, silicon carbide fiber, boron fiber, and metal fiber can be used. One type or two or more types may be used in combination. Among them, carbon fibers such as PAN-based, pitch-based, and rayon-based are preferable from the viewpoint of improving mechanical properties and reducing the weight of the molded product, and from the viewpoint of the balance between the strength and elastic modulus of the obtained molded product, PAN-based carbon. Fiber is more preferred. Further, for the purpose of imparting conductivity, reinforcing fibers coated with a metal such as nickel, copper or ytterbium can also be used.

The reinforcing fiber (C) may be used as a reinforcing fiber bundle in which a plurality of single yarns are bundled from the viewpoint of handleability. The number of single yarns constituting the reinforcing fiber bundle is preferably 1000 or more, and more preferably 10,000 or more and 350,000 or less from the viewpoint of handleability. The larger the number of single yarns constituting the reinforcing fiber bundle, the more economical the obtained molding material is, but the more the fiber dispersibility during molding tends to decrease. Therefore, by setting the number of single yarns constituting the reinforcing fiber bundle in such a range, the effect of the molding material of the present invention can be efficiently exhibited.

Further, when carbon fiber is used as the reinforcing fiber (C) in the present invention, the surface is the ratio of the number of atoms of oxygen (O) and carbon (C) on the fiber surface measured by X-ray photoelectron spectroscopy (XPS). It is preferable that the oxygen concentration ratio (O / C) is 0.05 or more and 0.5 or less. The higher the surface oxygen concentration ratio (O / C), the larger the amount of functional groups on the surface of the carbon fiber, and the adhesiveness between the carbon fiber and the matrix resin can be improved, while the surface oxygen concentration ratio (O / C) is high. If it is too high, there is a concern that the crystal structure on the surface of the carbon fiber may be destroyed, and there is a concern that the strength of the carbon fiber itself may decrease. Therefore, when the surface oxygen concentration ratio (O / C) is within the above preferable range, the mechanical properties It is possible to obtain a particularly excellent molded product.

The surface oxygen concentration ratio (O / C) is determined by X-ray photoelectron spectroscopy according to the following procedure. First, the carbon fibers after removing impurities with a solvent are cut, spread on a copper sample support and arranged, and then the photoelectron escape angle is set to 90 °, MgK _α1 and 2 are used as an X-ray source, and the sample chamber is used. Keep the inside at ^{1x10-8 Torr.} The kinetic energy value (KE) of the main peak of C1S is adjusted to 969 eV as a correction of the peak due to charging at the time of measurement. The C1S peak area is K.I. E. It is obtained by drawing a straight baseline in the range of 958 eV to 972 eV. The O1S peak area is K.I. E. It is obtained by drawing a straight line baseline in the range of 714 eV to 726 eV. Here, the surface oxygen concentration ratio (O / C) is calculated as an atomic number ratio from the ratio of the O1S peak area and the C1S peak area using a sensitivity correction value peculiar to the apparatus.

The means for controlling the surface oxygen concentration ratio (O / C) is not particularly limited, but for example, methods such as electrolytic oxidation treatment, chemical solution oxidation treatment, and gas phase oxidation treatment can be taken, and among them, electrolysis. Oxidation treatment is preferred.

In the present invention, the reinforcing fiber (C) is preferably a carbon fiber (F) surface-treated with the polyfunctional compound (E). With such a configuration, the compound (B) can be efficiently adhered to the reinforcing fibers (C) in the step of manufacturing the molding material, and the fiber dispersibility when molding the obtained molding material can be controlled, which is preferable. ..

As the polyfunctional compound (E), a compound having two or more functional groups such as an epoxy group, a urethane group, an amino group, and a carboxyl group in one molecule can be used, and these may be used alone or in combination of two or more. May be good. If the number of functional groups is less than two, the adhesive force of the reinforcing fiber (C) to the compound (B) in the molding material may be insufficient. Therefore, the number of functional groups is preferably 2 or more, and more preferably 3 or more.

Specific examples of the polyfunctional compound (E) include a polyfunctional epoxy resin. Examples of the polyfunctional epoxy resin include bisphenol A type epoxy resin, bisphenol F type epoxy resin, aliphatic epoxy resin, and phenol novolac type epoxy resin. Of these, an aliphatic epoxy resin is preferable because it has excellent flexibility even after the cross-linking reaction and is difficult to peel off from the reinforcing fibers and the compound (B) in the state of the molding material.

Specific examples of the aliphatic epoxy resin include, for example, in the diglycidyl ether compound, ethylene glycol diglycidyl ether, polyethylene glycol diglycidyl ethers, propylene glycol diglycidyl ether, polypropylene glycol diglycidyl ethers, 1,4- Examples thereof include butanediol diglycidyl ether, neopentyl glycol diglycidyl ether, polytetramethylene glycol diglycidyl ether, and polyalkylene glycol diglycidyl ethers. Among the polyglycidyl ether compounds, glycerol polyglycidyl ether, diglycerol polyglycidyl ether, polyglycerol polyglycidyl ethers, sorbitol polyglycidyl ethers, arabitol polyglycidyl ethers, trimethylolpropane polyglycidyl ethers, trimethylolpropane Examples thereof include glycidyl ethers, pentaerythritol polyglycidyl ethers, and polyglycidyl ethers of aliphatic polyhydric alcohols.

Among the aliphatic epoxy resins, the polyfunctional compound (E) is selected from glycerol polyglycidyl ether, diglycerol polyglycidyl ether, polyethylene glycol diglycidyl ether, and polypropylene glycol diglycidyl ether from the viewpoint of having many highly reactive glycidyl groups. It is preferable that the amount is at least one. By forming the polyfunctional compound (E) in such a configuration, the adhesion between the reinforcing fibers (C) and the compound (B) in the state of the molding material is excellent, and the fiber dispersibility when molding the obtained molding material is further improved. It is preferable because it can be controlled.

The molding material of the present invention contains 30 parts by mass or more and 98.9 parts by mass or less of the thermoplastic resin (A) with respect to a total of 100 parts by mass of the thermoplastic resin (A), the compound (B) and the reinforcing fiber (C). The compound (B) is preferably 0.01 parts by mass or more and 20 parts by mass or less, and the reinforcing fiber (C) is preferably 1 part by mass or more and 50 parts by mass or less.

The thermoplastic resin (A) is more preferably 50 parts by mass or more and 70 parts by mass or less. By setting the thermoplastic resin (A) within such a range, the fiber dispersibility of the reinforcing fibers (C) at the time of injection molding is improved, and the portion where the reinforcing fibers (C) are densely packed in the obtained molded product, or the opposite. Prevents the occurrence of a portion where the reinforcing fiber (C) does not exist.

The compound (B) is more preferably 0.01 parts by mass or more and 10 parts by mass or less. By setting the compound (B) within such a range, it is possible to easily obtain the resin-attached reinforcing fiber (D) obtained by adhering the compound (B) to the reinforcing fiber (C). When it is 0.01 part by mass or more, the fiber dispersibility of the reinforcing fiber (C) in the molded product is improved. Further, when the amount is 20 parts by mass or less, the compound (B) can be sufficiently diffused into the thermoplastic resin (A), thereby improving the effect as an impregnation aid / dispersion aid described later and strengthening the molded product. The fiber dispersibility of the fiber (C) is improved.

The reinforcing fiber (C) is more preferably 5 parts by mass or more and 40 parts by mass or less. In general, the larger the amount of reinforcing fibers (C), the better the mechanical properties of the obtained molded product, and the lower the fiber dispersibility tends to be. In the present application, it is possible to obtain a molded product having excellent mechanical properties and fiber dispersibility within such a range. When the amount is 1 part by mass or more, the fiber dispersibility and mechanical properties of the reinforcing fiber (C) in the molded product are improved. In the case of 50 parts by mass or less, the fiber dispersibility of the reinforcing fiber (C) in the molded product is improved.

The molding material of the present invention preferably has a high viscosity retention rate calculated by the following formula (1).
(Viscosity retention rate during melt-kneading of the thermoplastic resin (A) and compound (B)) = (Viscosity at cylinder temperature during injection molding of the mixture of the thermoplastic resin (A) and compound (B) [Pa · s] ]) / (Melting viscosity [Pa · s] at the cylinder temperature during injection molding of the thermoplastic resin (A)) × 100 [%] ... Equation (1)

The viscosity retention rate of the thermoplastic resin (A) and the compound (B) at the time of melt-kneading is preferably 50% or more, more preferably 60% or more, still more preferably 90% or more. The molding material of the present invention is a molding material in which a resin-bonded reinforcing fiber (D) formed by adhering a compound (B) to a reinforcing fiber (C) and a thermoplastic resin (A) are bonded to each other, and is used during injection molding. By melt-kneading these in the cylinder of the above, a molded product in which the reinforcing fibers (C) are well dispersed can be obtained. When the viscosity retention rate of the thermoplastic resin (A) and the compound (B) during melt-kneading is 50% or more, the shearing force on the reinforcing fibers (C) is likely to be applied, and the reinforcing fibers (reinforcing fibers) in the molded product ( The dispersion of C) is sufficient. The higher the viscosity retention rate of the thermoplastic resin (A) and the compound (B) during melt-kneading, the easier it is to disperse the reinforcing fibers (C) in the cylinder of the injection molding machine, which is preferable. Generally, as the mass ratio of the reinforcing fiber (C) increases, the amount of the impregnating aid / dispersion aid required to disperse the reinforcing fiber (C) in the molded product tends to increase. By setting the viscosity retention rate at the time of melt mixing with the compound (B) within the above range, even if the mass ratio of the reinforcing fiber (C) is increased, the amount of the impregnating aid / dispersion aid is not increased. It is preferable because the dispersibility of the reinforcing fiber (C) in the molded product can be efficiently increased.

The molding material of the present invention preferably has high compatibility between the thermoplastic resin (A) and the compound (B) in the relationship between the thermoplastic resin (A) and the compound (B) constituting the molding material. As an index of such compatibility, the melt obtained by mixing the thermoplastic resin (A) and the compound (B) and heating and kneading them at the same temperature as the injection molding temperature is observed with an optical microscope at a magnification of 200 times. Then, the number average particle size of the compound (B) dispersed as an island layer in the sea layer of the thermoplastic resin (A) observed at that time can be mentioned. Regarding the compatibility between the thermoplastic resin (A) and the compound (B), the number average particle size of the compound (B) is preferably less than 10 μm, more preferably less than 1 μm, and the particles of the compound (B) are not observed. More preferred. By setting the compatibility between the thermoplastic resin (A) and the compound (B) within such a range, the dispersibility of the compound (B) in the thermoplastic resin (A) can be improved with respect to the single yarn of the reinforcing fiber (C). Is also preferable because it can be made sufficiently small and the reinforcing fibers (C) can be easily dispersed in the cylinder of the injection molding machine.

The molding material of the present invention has better fiber dispersibility in the molded product when the viscosity retention rate and the number average particle size of the compound (B) are in the preferable ranges.

The molding material of the present invention is a molding material in which a resin-bonded reinforcing fiber (D) formed by adhering a compound (B) to a reinforcing fiber (C) and a thermoplastic resin (A) are bonded to each other. The form of the resin-adhered reinforcing fiber (D) is as shown in FIG. 1, and the compound (B) is filled between each single fiber of the reinforcing fiber (C). That is, the reinforcing fibers (C) are dispersed like islands in the sea of the compound (B). When the reinforcing fiber (C) is a carbon fiber (F) surface-treated with the polyfunctional compound (E), the carbon fiber (F) is dispersed like an island in the sea of the compound (B). It becomes.

The compound (B) adheres to the reinforcing fiber (C) to form the resin-attached reinforcing fiber (D). When a molding material in which the thermoplastic resin (A) is bonded to the resin adhesion reinforcing fiber (D) is injection-molded, for example, the compound (B) melt-kneaded in the cylinder of the injection molding machine is the thermoplastic resin (A). The reinforcing fiber (C) is dispersed in the thermoplastic resin (A), and at the same time, the thermoplastic resin (A) is replaced and impregnated with the reinforcing fiber (C). The compound (B) here has a role as a so-called impregnation aid / dispersion aid.

As a step of adhering the compound (B), a known production method such as applying an oil agent, a sizing agent, or a matrix resin to the fiber bundle can be used, but as a more specific example, it is applied to the surface of a heated rotating roll. By coating a film of the molten compound (B) with a certain thickness and running while adhering the reinforcing fibers (C) to the surface of the roll, a predetermined amount of the compound (C) per unit length of the reinforcing fibers (C) ( A method of adhering B) can be mentioned. The coating of the compound (B) on the roll surface can be realized by applying the concept of a known coating device such as a reverse roll, a forward rotation roll, a kiss roll, a spray, a curtain, and an extrusion. The coating equipment on the roll is described in detail in works such as "Introduction to Coating Equipment and Operation Technology" by Yuji Harasaki (General Technology Center).

In the step of adhering the compound (B) to the reinforcing fiber (C), tension is applied to the reinforcing fiber (C) to which the compound (B) is attached with a roll or a bar at a temperature at which the compound (B) melts. The compound (B) is impregnated up to the space between the single yarns of the reinforcing fiber (C) by repeating widening and focusing, applying pressure and vibration, and the like. As a more specific example, a method of passing the reinforcing fibers (C) through the surfaces of a plurality of heated rolls or bars so as to be in contact with each other can be mentioned.

In the molding material of the present invention, the resin-adhered reinforcing fiber (D) composed of the reinforcing fiber (C) and the compound (B) is formed in contact with the thermoplastic resin (A). As a step of arranging the thermoplastic resin (A), the molten thermoplastic resin (A) is arranged so as to be in contact with the resin adhesion reinforcing fiber (D). More specifically, using an extruder and a coating die for the wire coating method, a method of continuously arranging the resin adhesion reinforcing fiber (D) so as to coat the thermoplastic resin (A) around the resin adhesion reinforcing fiber (D). , A method of arranging a film-like thermoplastic resin (A) melted by using an extruder and a T-die from one side or both sides of a resin-adhered reinforcing fiber (D) flattened by a roll or the like and integrating them with a roll or the like. Can be mentioned.

After the resin adhesion reinforcing fiber (D) is integrated with the thermoplastic resin (A), it may be cut to a certain length with a device such as a pelletizer or a strand cutter for use. This cutting step may be continuously installed after the placement step of the thermoplastic resin (A). When the molding material is flat or sheet-like, it may be slit and elongated before cutting. You may use something like a sheet pelletizer that slits and cuts at the same time.

The molding material of the present invention is a molding material configured by arranging the thermoplastic resin (A) so as to adhere to the resin adhesion reinforcing fiber (D). In a preferred embodiment of the molding material, as shown in FIG. 2, the reinforcing fibers (C) are arranged substantially parallel to the axial direction of the molding material, and the length of the reinforcing fibers (C) is the length of the molding material. It is virtually the same length. The molding material of the present invention is preferably a cylinder such as a pellet, and the axial direction refers to the axial direction of the cylinder.

Here, "arranged almost in parallel" means that the long axis of the reinforcing fiber bundle made of the reinforcing fibers (C) and the long axis of the molding material are oriented in the same direction. It indicates a state, and the deviation of the angle between the axes is preferably 20 ° or less, more preferably 10 ° or less, and further preferably 5 ° or less. Further, "substantially the same length" means, for example, in a pellet-shaped molding material, a reinforcing fiber bundle is cut in the middle of the inside of the pellet, or a reinforcing fiber bundle significantly shorter than the total length of the pellet is substantially included. It is not to be missed. In particular, the amount of the reinforcing fiber bundle shorter than the total length of the pellet is not specified, but when the content of the reinforcing fiber having a length of 50% or less of the total length of the pellet is 30% by mass or less, the pellet It is evaluated that the reinforcing fiber bundle significantly shorter than the total length is not substantially contained. Further, the content of the reinforcing fiber (C) having a length of 50% or less of the total length of the pellet is preferably 20% by mass or less. The total length of the pellet is the length in the direction of the reinforcing fibers in the pellet. Since the reinforcing fiber (C) has a length equivalent to that of the molding material, the length of the reinforcing fiber in the molded product can be lengthened, so that excellent mechanical properties can be obtained.

3 to 4 schematically show an example of the shape of the axial cross section of the molding material of the present invention, and FIGS. 5 to 8 show an example of the shape of the orthogonal cross section of the molding material of the present invention. It is a schematic representation.

The shape of the cross section of the molding material is not limited to that shown in the figure as long as the thermoplastic resin (A) is arranged so as to adhere to the resin adhesion reinforcing fiber (D), but the cross section in the axial direction is preferable. As shown in FIG. 3, it is preferable that the composite is a core material and is sandwiched between layers of the thermoplastic resin (A).

Further, as shown in FIGS. 5 to 7 which are cross sections in the orthogonal direction, the resin adhesion reinforcing fiber (D) has a core structure, and the thermoplastic resin (A) has a sheath structure. The molding material preferably has a core-sheath structure in which the thermoplastic resin (A) covers the periphery of the resin adhesion reinforcing fiber (D). When a plurality of resin adhesion reinforcing fibers (D) as shown in FIG. 9 are arranged so as to be covered with the thermoplastic resin (A), the number of resin adhesion reinforcing fibers (D) is 2 or more and 6 or less. desirable.

The boundary between the resin adhesion reinforcing fiber (D) and the thermoplastic resin (A) is adhered, and the thermoplastic resin (A) partially enters a part of the resin adhesion reinforcing fiber (D) near the boundary, and the resin adhesion reinforcing fiber It may be in a state of being compatible with the compound (B) in (D) or in a state of being impregnated with the reinforcing fiber (C).

The axial direction of the molding material may be continuous while maintaining substantially the same cross-sectional shape. Depending on the molding method, such a continuous molding material may be cut to a certain length.

By using the molding material of the present invention, the thermoplastic resin (A) can be kneaded with the resin adhesion reinforcing fiber (D) by, for example, injection molding to prepare a final molded product. From the viewpoint of handleability of the molding material, it is preferable that the resin adhesion reinforcing fiber (D) and the thermoplastic resin (A) are not separated until molding is performed and maintain the shape as described above. Since the shape (size, aspect ratio), specific gravity, and mass of the resin adhesion reinforcing fiber (D) and the thermoplastic resin (A) are completely different, they are classified during transportation and handling of the material until molding, and during material transfer in the molding process. However, the mechanical properties of the molded product may vary, the fluidity may decrease, causing mold clogging, or blocking may occur in the molding process.

Therefore, as illustrated in FIGS. 5 to 8, the molding material has a core-sheath structure in which the thermoplastic resin (A) serves as a sheath and covers the periphery of the resin-attached reinforcing fiber (D) which is the core, or a resin. It is preferable to have a structure in which the adhesion reinforcing fiber (D) and the thermoplastic resin (A) are arranged in layers. Due to the ease of manufacturing and the ease of handling the material, the thermoplastic resin (A) may be arranged so as to cover the periphery of the resin adhesion reinforcing fiber (D) as illustrated in FIGS. 5 to 7. More preferable.

As mentioned above, it is desirable that the reinforcing fiber (C) is completely impregnated with the compound (B) and a part of the thermoplastic resin (A), but in reality it is difficult and the reinforcing fiber (C) There are some voids in the composite composed of the compound (B) and a part of the thermoplastic resin (A). In particular, when the content of the reinforcing fibers (C) is large, the number of voids tends to increase, but even when some voids are present, the effect of impregnation and promotion of fiber dispersion by the compound (B) is shown. However, when the porosity is 20% or less, the effect of impregnation and fiber dispersion promotion can be remarkably obtained, so that the porosity is preferably in the range of 20% or less. Porosity is determined by measuring the portion of the composite by the ASTM D2734 (1997) test method or by using reinforcing fibers (C) and compound (B) and some (thermoplastic resin (A)) in the cross section of the molding material. By observing the voids existing in the formed complex portion, it can be calculated from the total area of the complex portion and the total area of the void portion by using the following equation.
Porosity (%) = total area of voids / (total area of complex + total area of voids) x 100.

The molding material of the present invention is preferably used by cutting into a length in the range of 1 mm or more and 50 mm or less. By adjusting to the above length, the fluidity and handleability at the time of molding can be sufficiently improved. A particularly preferable embodiment of the molding material cut to such an appropriate length can be exemplified by long fiber pellets for injection molding.

The molding material of the present invention can be processed into a molded product by injection molding, and it is preferable that the reinforcing fibers (C) are dispersed in a single yarn shape in the molded product. As a method of confirming that the fibers are dispersed in the form of a single thread, the residual rate of the resin adhesion reinforcing fiber (D) in the molded product is a guide. That is, it is preferable that the resin-adhered reinforcing fibers (D) are consumed during the injection molding of the molding material of the present invention, and the reinforcing fibers (C) are dispersed in a single thread shape. The term "dispersed in a single yarn form" means that the single yarns of a plurality of adjacent reinforcing fibers (C) are not parallel to each other in the length direction thereof, or are not in contact with each other even if they are parallel to each other. Is shown. When multiple adjacent single yarns are parallel and in contact with each other, they are in an undispersed state. When a large number of undispersed resin-adhered reinforcing fibers (D) are present, the appearance of the molded product is spoiled, and the ends of the reinforcing fibers (C) where stress tends to be concentrated under load are locally concentrated. Since cracks that lead to breakage are more likely to occur, the mechanical properties of the molded product are deteriorated.

The number average fiber length of the reinforcing fibers (C) in the molded product obtained by the molding material of the present invention is preferably in the range of 0.3 mm or more and 10 mm or less. It is more preferably in the range of 0.5 mm or more and 10 mm or less. Within such a range, the effect and efficiency of reinforcing the thermoplastic resin (A) in the molded product with the reinforcing fibers (C) can be enhanced, and the mechanical properties of the molded product can be sufficiently enhanced. Here, a method for measuring the number average fiber length in the molded product will be described. As a method for measuring the number average fiber length of the reinforcing fibers (C) contained in the molded product, for example, the resin component contained in the molded product is removed by a melting method or a burning method, and the remaining reinforcing fibers (C) are used. ) Is filtered and then measured by microscopic observation. For the measurement, 400 reinforcing fibers (C) are randomly selected, the length thereof is measured with an optical microscope up to 1 μm, and the total fiber length is divided by the number to calculate the number average fiber length.

The molded product obtained from the molding material of the present invention is suitable for automobile parts such as instrument panels, door beams, undercovers, lamp housings, pedal housings, radiator supports, spare tire covers, front ends and other modules. Further examples include household and office electrical appliances such as telephones, facsimiles, VTRs, copiers, televisions, microwave ovens, audio equipment, toiletries, refrigerators and air conditioners. Further, a housing used for a personal computer, a mobile phone, etc., and a member for an electric / electronic device represented by a keyboard support which is a member for supporting a keyboard inside the personal computer can be mentioned. The present invention is more preferable when a conductive carbon fiber is used as the reinforcing fiber because the electromagnetic wave shielding property is imparted to such a member for an electric / electronic device.

Examples will be shown below, and the present invention will be described in more detail. First, the evaluation method used in the present invention is described below.

(1) Viscosity retention rate during melt mixing of thermoplastic resin (A) and compound (B) Using a viscoelasticity measuring instrument (manufactured by Anton Pearl Japan), using a 40 mm parallel plate, under 0.5 Hz conditions The melt viscosity of the thermoplastic resin (A) or the mixture of the thermoplastic resin (A) and the compound (B) was measured in the temperature range of 150 ° C. to 300 ° C. The viscosity retention rate at the time of melt mixing of the thermoplastic resin (A) and the compound (B) was determined by the following formula (2).
(Viscosity retention rate during melt-kneading of the thermoplastic resin (A) and compound (B)) = (Viscosity at cylinder temperature during injection molding of the mixture of the thermoplastic resin (A) and compound (B) [Pa · s] ]) / (Melting viscosity [Pa · s] at the cylinder temperature during injection molding of the thermoplastic resin (A)) × 100 [%] ... Equation (2)
The viscosity retention rate of the molding material having each constitution at the time of melt-kneading was judged according to the following criteria, and a fair or higher was regarded as acceptable.
excellent: Viscosity retention rate during melt-kneading is 90% or more good: Viscosity retention rate during melt-kneading is 60% or more and less than 90% fair: Viscosity retention rate during melt-kneading is 50% or more and less than 60% bad: The viscosity retention rate at the time of melt-kneading is less than 50%.

(2) Compatibility of Thermoplastic Resin (A) and Compound (B) Thermoplastic Resin (A) and Compound (B) are mixed and heat-kneaded at the same temperature as the cylinder temperature at the time of injection molding. The melt is observed with an optical microscope at a magnification of 200 times, and the diameter of the particles of the compound (B) dispersed as an island layer in the sea layer of the thermoplastic resin (A) observed at that time is measured up to 1 μm. The number average particle size (Rn) was calculated by the following equation.
Number average particle size (Rn) = (ΣRi) / Nr
Ri: Measured particle diameter (i = 1, 2, 3, ..., N)
-Nr: Total number of particles whose diameters were measured The number of average fiber diameters in the molded product was determined according to the following criteria, and good or higher was regarded as acceptable.
excellent: No dispersed particles are observed, or the number average particle size of the dispersed particles is less than 1 μm good: The number average particle size of the dispersed particles is 1 μm or more and less than 10 μm bad: The number average particle size of the dispersed particles is 10 μm or more.

(3) Number average fiber length of reinforcing fibers (C) contained in the molded product A sample obtained by cutting out a part of the molded product is heated in air at a temperature of 500 ° C. for 30 minutes using an electric furnace to heat it. The plastic resin (A) and the compound (B) were sufficiently incinerated and removed to separate the reinforcing fibers (C). At least 400 separated reinforcing fibers (C) were randomly extracted, their lengths were measured to a unit of 1 μm with an optical microscope, and the number average fiber length (Ln) was determined by the following formula.
Number average fiber length (Ln) = (ΣLi) / Nf
Li: Measured fiber length (i = 1, 2, 3, ..., N)
-Nf: The total number of fibers whose fiber length was measured The average fiber length in the molded product was determined according to the following criteria, and a good or higher was accepted.
excellent: Number average fiber length is 0.5 mm or more and less than 10 mm good: Number average fiber length is 0.3 mm or more and less than 0.5 mm bad: Number average fiber length is less than 0.3 mm.

(4) Fiber dispersibility in molded product A resin-adhered reinforcing fiber (D) in which a 100 mm × 100 mm × 2 mm molded product was molded and the reinforcing fibers (C) remained without being dispersed during injection molding on each of the front and back surfaces. ) Was visually counted. Counting was performed on the resin-attached reinforcing fiber (D) having a length of 1 mm or more. The evaluation was performed on 50 molded products, and the fiber dispersibility was judged based on the following criteria for the number average number converted per molded product, and fair or higher was regarded as acceptable.
excellent: Less than 1 resin adhesion reinforcing fiber (D) good: 1 or more and less than 5 resin adhesion reinforcing fibers (D) fair: 5 or more and less than 10 resin adhesion reinforcing fibers (D) bad: Resin adhesion reinforcement 10 or more fibers (D).

(Reference Example 1) (CF-1)
By performing spinning, firing treatment, and surface oxidation treatment using a copolymer containing polyacrylonitrile as a main component, a continuous carbon fiber bundle having a total number of single yarns of 24,000 was obtained. This carbon fiber was measured by the following measuring method.

<Measurement of single fiber diameter of carbon fiber>
The carbon fiber single yarn was observed with a scanning electron microscope (SEM), and the diameter was measured. The measurement was performed on 20 carbon fiber bundles, and the average value was taken as the single fiber diameter of the carbon fibers.

<Measurement of mass per unit length>
The obtained carbon fiber bundle was cut out to a length of 1 m, and the mass was measured. The measurement was performed on five carbon fiber bundles, and the average value was taken as the mass per unit length.

<Measurement of specific gravity>
The specific gravity of the carbon fiber was measured by the submerged substitution method.

<Surface oxygen concentration>
The surface oxygen concentration ratio of the carbon fibers was determined by X-ray photoelectron spectroscopy according to the following procedure. First, by cutting the carbon fiber bundle to 20 mm, after aligned spread on copper sample holder, keeping the sample chamber to 1 × 10 ⁸ Torr. Measurements were made using A1Kα1 and 2 as the X-ray source. The kinetic energy value (KE) of the main peak of C1s was adjusted to 1202 eV as a correction value of the peak due to charging at the time of measurement. The C1s peak area was determined by K.I. E. It was obtained by drawing a straight baseline in the range of 1191 eV to 1205 eV. The O1s peak area was determined by K.I. E. It was obtained by drawing a straight baseline in the range of 947 eV to 959 eV. From the ratio of the O1s peak area and the C1s peak area, O / C was calculated as the atomic number ratio using the sensitivity correction value peculiar to the apparatus. A model ES-200 manufactured by Kokusai Electric Inc. was used as an X-ray photoelectron spectroscopy apparatus, and the sensitivity correction value was set to 1.74.

<Measurement of strand tensile strength and tensile elastic modulus of carbon fiber>
The carbon fiber bundle is impregnated with "Ceroxide (registered trademark)" 2021P (manufactured by Daicel Chemical Industry Co., Ltd.) / Borone monoethylamine trifluoride (manufactured by Tokyo Chemical Industry Co., Ltd.) / Acetone = 100/3/4 (part by mass). After curing at a temperature of 130 ° C. for 30 minutes, a tensile test was performed based on JIS R7608 (2007). The measurement was performed on 10 strands, and the strand tensile strength and tensile elastic modulus were determined by average values.
Single fiber diameter: 7 μm
Mass per unit length: 1.6 g / m
Relative density: 1.8
Surface oxygen concentration ratio [O / C]: 0.06
Tensile strength: 4600 MPa
Tensile modulus: 220 GPa.

As a polyfunctional compound, a sizing agent mother liquor in which glycerol triglycidyl ether was dissolved in water so as to be 2% by mass was prepared, a sizing agent was added to the carbon fiber bundle by an immersion method, and the mixture was dried at 230 ° C. .. The amount of adhesion was 1.0% by mass.

(Reference Example 2) Acid-modified polypropylene propylene homopolymer (Prime Polypro J105G resin manufactured by Prime Polymer Co., Ltd.) 99.6 parts by mass, maleic anhydride 0.4 parts by mass, and Perhexi 25B (Nippon Yushi (Nippon Yushi)) as a polymerization initiator. (Manufactured by Co., Ltd.) 0.4 parts by mass are mixed and modified at a heating temperature of 160 ° C. for 2 hours to obtain (A-1) acid-modified polypropylene resin (Mw = 400,000, acid content = 0.08 mmol equivalent). ) Was obtained. Furthermore, 30% by mass of (A-1) acid-modified polypropylene resin and 70% by mass of (PP-1) Prime Polypro J105G resin manufactured by Prime Polymer Co., Ltd. are combined with a TEX-30α twin-screw extruder (screw) manufactured by Japan Steel Works, Ltd. ^{PP-2 (density 0.9 g / cm 3} ) was obtained by melt-kneading at 230 ° C. with a diameter of 30 mm and L / D = 32).

<Compound (B)>
(B-1): C9-based petroleum resin (Arcon M135 manufactured by Arakawa Chemical Industries, Ltd .: resin composed of a polymer polymerized using a C9-based petroleum fraction as a main component)
(B-2): C9-based petroleum resin (Arcon P125 manufactured by Arakawa Chemical Industry Co., Ltd .: A resin composed of a polymer obtained by hydrogenating a polymer polymerized using a C9-based petroleum fraction as a main component)
(B-3): C5 petroleum resin (Idemitsu Kosan Co., Ltd. Imarve P125: resin composed of hydrogenated polymer obtained by polymerizing using C5 petroleum fraction as the main component)
(B-4): Terpene resin (YS resin PX1250 manufactured by Yasuhara Chemical Co., Ltd .: a resin composed of a polymer polymerized using α-pinene and β-pinene as main components)
(B-5): Hydrogenated terpene resin (Clearlon P-105 manufactured by Yasuhara Chemical Co., Ltd .: A resin composed of a polymer obtained by hydrogenating a polymer polymerized using d-limonene as a main component).
(B-6): Terpene phenol resin (YP90L manufactured by Yasuhara Chemical Co., Ltd .: a resin composed of a polymer polymerized using a monocyclic monoterpene and phenol as main components).

(Example 1)
A liquid film was formed on a roll heated at 130 ° C. by heating and melting (B-1) C9 petroleum resin as compound (B). A kiss coater was used to form a film of constant thickness on the roll. A continuous carbon fiber bundle made of CF-1 obtained from Reference Example 1 was passed through and adhered to the roll as a reinforcing fiber (C) while being in contact with each other. Next, ten rolls of 50 mm in diameter arranged in a straight line, which were heated to 180 ° C. and freely rotated by bearings, were passed alternately above and below. By this operation, the compound (B) was impregnated into the inside of the fiber bundle of the reinforcing fiber (C) to form the resin-attached reinforcing fiber (D). This continuous resin adhesion reinforcing fiber (D) is applied to a coating die for the wire coating method installed at the tip of a TEX-30α twin-screw extruder (screw diameter 30 mm, L / D = 32) manufactured by Nippon Steel Works Co., Ltd. (PP-1) polyolefin (Prime Polypro J105G resin manufactured by Prime Polymer Co., Ltd., density 0.9 g / cm ³ ) was used as the thermoplastic resin (A) melted in a die at 230 ° C. through the extruder. It was discharged and continuously arranged so as to cover the periphery of the resin adhesion reinforcing fiber (D). At this time, the mass of the thermoplastic resin (A), the compound (B), and the reinforcing fiber (C) depends on the take-up speed of the reinforcing fiber (C) and the supply speed of the thermoplastic resin (A) and the compound (B). Adjusted. After cooling the obtained molding material, it was cut with a cutter so that the length of the fiber bundle of the encapsulating reinforcing fiber (C) was 7 mm to obtain a pellet-shaped molding material.

Next, the obtained pellet-shaped molding material was injection-molded at a cylinder temperature of 220 ° C. and a mold temperature of 60 ° C. using a J350EIII type injection molding machine manufactured by Japan Steel Works, Ltd. to obtain a molded product. It was. Next, the obtained molded product was evaluated according to the above evaluation method. The results obtained are shown in Table 1.

(Examples 2 and 3, Comparative Examples 1 to 3)
Using the raw materials shown in Table 1, the molding material was produced and the molded product was evaluated in the same manner as in Example 1.

From the comparison between Examples 1 to 3 and Comparative Examples 1 to 3 in Table 1, it is clear that a molded product having excellent fiber dispersibility can be obtained by using the petroleum resin as the compound (B).

In Example 2 of Table 1, since C9 petroleum resin hydrogenated to compound (B) was used, a molded product having better fiber dispersibility was obtained as compared with Examples 1 and 3.

(Example 4)
The molding material was produced and the molded product was evaluated in the same manner as in Example 1 except that the thermoplastic resin (A) was replaced with PP-2 obtained from Reference Example 2. The results obtained are shown in Table 2.

(Example 5, Example 6, Comparative Examples 4 to 6)
Using the raw materials shown in Table 2, the molding material was produced and the molded product was evaluated in the same manner as in Example 4.

By comparing Examples 4 to 6 in Table 2 with Comparative Examples 4 to 6, it is clear that by using a petroleum resin as the compound (B), a molded product having excellent fiber dispersibility can be obtained.

In Example 5 of Table 2, since C9 petroleum resin hydrogenated to compound (B) was used, a molded product having better fiber dispersibility was obtained as compared with Examples 4 and 6.

(Example 7)
A polymer polymerized on a roll heated at 130 ° C. using (B-1) C9-based petroleum resin as compound (B) (Arcon M135 manufactured by Arakawa Chemical Industry Co., Ltd .: C9-based petroleum fraction as the main component. A liquid film was formed by heating and melting (resin made of). A kiss coater was used to form a film of constant thickness on the roll. A continuous carbon fiber bundle made of CF-1 obtained from Reference Example 1 was passed through and adhered to the roll as a reinforcing fiber (C) while being in contact with each other. Next, ten rolls of 50 mm in diameter arranged in a straight line, which were heated to 180 ° C. and freely rotated by bearings, were passed alternately above and below. By this operation, the compound (B) was impregnated into the inside of the fiber bundle of the reinforcing fiber (C) to form the resin-attached reinforcing fiber (D). This continuous resin adhesion reinforcing fiber (D) is applied to a coating die for the wire coating method installed at the tip of a TEX-30α twin-screw extruder (screw diameter 30 mm, L / D = 32) manufactured by The Japan Steel Works, Ltd. As the thermoplastic resin (A) that was passed through and melted in the die from the extruder to 240 ° C., (PA-1) nylon 6 resin (“Amiran” CM1017 manufactured by Toray Co., Ltd., density 1.13 g / cm ³⁾ ) Was discharged and continuously arranged so as to cover the periphery of the resin adhesion reinforcing fiber (D). At this time, the mass of the thermoplastic resin (A), the compound (B), and the reinforcing fiber (C) depends on the take-up speed of the reinforcing fiber (C) and the supply speed of the thermoplastic resin (A) and the compound (B). Adjusted. After cooling the obtained molding material, it was cut with a cutter so that the length of the fiber bundle of the encapsulating reinforcing fiber (C) was 7 mm to obtain a pellet-shaped molding material.

Next, the obtained pellet-shaped molding material was injection-molded at a cylinder temperature of 250 ° C. and a mold temperature of 70 ° C. using a J350EIII type injection molding machine manufactured by Japan Steel Works, Ltd. to obtain a molded product. It was. Next, the obtained molded product was evaluated according to the above evaluation method. The results obtained are shown in Table 3.

(Examples 8 and 9, Comparative Examples 7 to 9)
Using the raw materials shown in Table 3, the molding material was produced and the molded product was evaluated in the same manner as in Example 7.

From the comparison between Examples 7 to 9 and Comparative Examples 7 to 9 in Table 3, it is clear that a molded product having excellent fiber dispersibility can be obtained by using the petroleum resin as the compound (B).

In Example 8 of Table 3, since C9 petroleum resin hydrogenated to compound (B) was used, a molded product having better fiber dispersibility was obtained as compared with Examples 7 and 9.

(Example 10)
The production of the molding material and the evaluation of the molded product were carried out in the same manner as in Example 1 except that the amount of the thermoplastic resin (A) was replaced with 70 parts by mass and the amount of the reinforcing fiber (C) was replaced with 20 parts by mass. went. The results obtained are shown in Table 4.

(Examples 11-12)
Using the raw materials shown in Table 4, the molding material was produced and the molded product was evaluated in the same manner as in Example 10.

From Examples 10 to 12 in Table 4, it is clear that a molded product having excellent fiber dispersibility can be obtained even when the content of the reinforcing fibers (C) is 20 parts by mass.

1 Reinforcing fiber (C)
2 Compound (B)
3 Resin-adhered reinforcing fiber (D) formed by adhering compound (B) to reinforcing fiber (C).
4 Thermoplastic resin (A)

Claims (10)

The resin-adhered reinforcing fiber (D) and the thermoplastic resin (A) include a thermoplastic resin (A) and a resin-adhered reinforcing fiber (D) formed by adhering the compound (B) to the reinforcing fiber (C). The thermoplastic resin (A) is at least one thermoplastic resin selected from the group consisting of polyolefin, polyamide, polyester, polycarbonate, and polyarylene sulfide, and the compound (B). ) Is petroleum resin
The resin adhesion reinforcing fiber (D) has a core structure and has a core structure.
The thermoplastic resin (A) has a sheath structure and covers the periphery of the resin adhesion reinforcing fiber (D).
Reinforcing fiber (C) is arranged substantially parallel to the axial direction of the molding material and the length of the reinforcing fiber (C) is Ru length substantially the same length der of the molding material, the molding material. With respect to a total of 100 parts by mass of the thermoplastic resin (A), the compound (B) and the reinforcing fiber (C), the thermoplastic resin (A) is 30 parts by mass or more, 98.99 parts by mass or less, and the compound (B). ) Is 0.01 part by mass or more and 20 parts by mass or less, and the reinforcing fiber (C) is 1 part by mass or more and 50 parts by mass or less. The molding material according to claim 1 or 2, wherein the compound (B) is a resin containing 50% by mass or more of a polymer of a C9 fraction with respect to the entire compound (B). The molding material according to any one of claims 1 to 3, wherein the compound (B) is a polymer of at least one compound selected from the group consisting of vinyltoluene, indene, and α-methylstyrene. The molding material according to claim 3 or 4, wherein the compound (B) is a hydrogenated resin. The molding material according to any one of claims 1 to 5, wherein the thermoplastic resin (A) is polyolefin. The molding material according to any one of claims 1 to 6, wherein the reinforcing fiber (C) is a carbon fiber (F) surface-treated with a polyfunctional compound (E). The molding according to claim 7, wherein the polyfunctional compound (E) is at least one selected from the group consisting of glycerol polyglycidyl ether, diglycerol polyglycidyl ether, polyethylene glycol diglycidyl ether, and polypropylene glycol diglycidyl ether. material. The molding material according to any one of claims 1 to 8, which is a reinforcing fiber bundle composed of single fibers having 10,000 or more reinforcing fibers (C) and 350,000 or less reinforcing fibers. The molding material according to any one of claims 1 to 9, which is used for injection molding.

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