JP5655592B2 - Method for producing carbon fiber reinforced molding material - Google Patents

Description

The present invention relates to a method for producing a carbon fiber reinforced molding material. Specifically, the present invention relates to a method for producing a carbon fiber reinforced molding material by a take-up method.

  Fiber reinforced molding materials made of reinforced fibers such as carbon fibers and glass fibers and thermoplastic resins are excellent in specific strength and specific rigidity. Therefore, molding materials reinforced with various forms of reinforced fiber base materials are electric and electronic. Widely used in applications, civil engineering / architecture applications, automobile applications, aircraft applications, etc. In addition to the unidirectional continuous fiber base material and textile base material mainly aimed at increasing strength, the reinforcing fiber base material has a uniform distribution of reinforcing fiber to make the mechanical properties of the molded product isotropic. A chopped form or a chopped form for kneading with a thermoplastic resin is used. Furthermore, by using a molding material obtained by treating reinforcing fibers with a specific treating agent, there are many applications that can be applied if higher strength is developed. Therefore, various studies have been made so far on the production conditions of the fiber-reinforced molding material having excellent mechanical properties.

  In Patent Document 1, a reinforcing fiber obtained by applying a predetermined polymer to a reinforcing fiber and a molten thermoplastic resin are combined so that the reinforcing fiber, the polymer, and the thermoplastic resin have a predetermined blending ratio. A method for producing a fiber reinforced thermoplastic resin is disclosed.

  In Patent Document 2, as a reinforcing fiber of a fiber-reinforced thermoplastic resin molded body, it is a monofilamentous carbon fiber having a mass average fiber length of 0.5 to 10 mm, and an orientation parameter of −0.25 to In the method for producing a fiber-reinforced thermoplastic resin molded article using carbon fibers of 0.25, (I) a step of heating and melting the thermoplastic resin contained in the molding material, and (II) a step of arranging the molding material in the mold , (III) a step of pressurizing the molding material with a mold, (IV) a step of solidifying the molding material in the mold, and (V) a step of opening the mold and demolding the fiber-reinforced thermoplastic resin molded body. A manufacturing method is disclosed.

In Patent Document 3, a slurry stock solution containing a binder mainly composed of a non-combustible fibrous material and a thermoplastic resin as a main component and containing other predetermined components is applied to a traveling or rotating network or porous substrate. A method for producing a sheet-like material is disclosed that is supplied at an angle of 5 to 60 degrees with the surface of the substrate and then dehydrated and dried.
International Publication No. 2007/37260 Pamphlet International Publication No. 2007/97436 Pamphlet JP 58-69047 A

  The production method disclosed in Patent Document 1 merely applies a (meth) acrylic polymer component to a reinforced fiber web, and does not consider productivity such as subsequent take-up property, but widely as a fiber reinforced composite material. In order to utilize it, the improvement of the further manufacturing method was needed.

  In the production methods disclosed in Patent Documents 2 and 3, no special means is used for taking-up of the molding material. Therefore, it takes time and labor to produce the fiber-reinforced molding material. For the efficient production application, further improvement of the production method was required.

An object of this invention is to provide the manufacturing method of the carbon fiber reinforced molding material which can manufacture efficiently the fiber reinforced molding material from which the molded article excellent in a mechanical characteristic is obtained.

  The present invention for solving such problems comprises the following configurations [1] to [16].

[1] A method for producing a carbon fiber reinforced molding material comprising at least the following steps 1a, 2a, 3a and 4a.
1a: a process of processing a discontinuous carbon fiber bundle into a sheet-like carbon fiber substrate (A1) 2a: a side chain of 1 to 70% by mass of the carbon fiber substrate (A1) obtained in the step 1a Step (3a) for imparting 0.1 to 10% by mass of a (meth) acrylic polymer (B) having a hydroxyl group in the step (a) The (meth) acrylic polymer (B) obtained in Step 2a was imparted. Step 4a: Carbon obtained in step 3a, wherein the carbon fiber base material (A2) is composited so that the thermoplastic resin (C) is 20 to 98.9% by mass to obtain a carbon fiber reinforced molding material. A step of drawing the fiber reinforced molding material at a speed of 1 m / min or more.

[2] A method for producing a carbon fiber reinforced molding material including at least the following first 1b, 2b, and 3b steps.
1b: A discontinuous carbon fiber bundle with 0.1 to 10% by mass of a (meth) acrylic polymer (B) having a hydroxyl group in the side chain is processed into a sheet-like carbon fiber substrate (A2). Step 2b: Carbon fiber reinforced by compounding the carbon fiber substrate (A2) 1-70% by mass obtained in step 1b so that the thermoplastic resin (C) is 20-98.9% by mass. Step 3b for obtaining a molding material: a step of drawing the carbon fiber reinforced molding material obtained in the step 2b at a speed of 1 to 30 m / min.

[3] A method for producing a carbon fiber reinforced molding material including at least the following first c, second c, and third c steps.
1c: A discontinuous carbon fiber bundle is processed into a sheet-like carbon fiber substrate (A1), and at the same time a (meth) acrylic polymer (B) having a hydroxyl group in a side chain is converted into the carbon fiber substrate (A1). Step 2c for imparting 0.1 to 10% by mass to 1% to 70% by mass of the carbon fiber substrate (A2) to which (meth) acrylic polymer (B) obtained in Step 1c is imparted, and composite as thermoplastic resin (C) is 20 to 98.9 wt%, the 3c obtaining a carbon fiber-reinforced molding material: carbon fiber reinforced molding material obtained in the 2c step 1-30 m / The process of picking up at a rate of minutes.

[4] The carbon fiber reinforced molding according to any one of [1] to [3], wherein the carbon fiber substrate (A1) is a short fiber random orientation substrate obtained by the following method a. Material manufacturing method.
The method a: a step of introducing discontinuous carbon fiber bundle in the dispersion medium (i), and step (ii) the carbon fibers constituting the carbon fiber bundle to prepare a dispersion slurry in the dispersing medium, the slurry (Iii) to obtain a carbon fiber base material (A1) by removing the dispersion medium more, and the mass content of the carbon fiber in the slurry prepared in the step (ii) is C1, (Iii) C1 / C2 shall be 0.8 or more and 1.2 or less when the mass content of the carbon fiber in the slurry at the start is C2.

[5] The carbon fiber substrate (A2) provided with the (meth) acrylic polymer (B) obtained in any one of the steps 2a, 1b and 1c has a tensile strength of 1 N / cm or more. The method for producing a carbon fiber reinforced molding material according to any one of [1] to [4], which is taken up as a state.

[6] The method for producing a carbon fiber-reinforced molding material according to [4] or [5], wherein the mass content of the solid component in the slurry prepared in the step (ii) is 0.001 to 1% by mass. .

[7] In the step (i), the dispersion medium and the carbon fiber bundle are continuously charged into the dispersion tank, and the steps (i) to (iii) are continuously performed. [4] to [6] ] The manufacturing method of the carbon fiber reinforced molding material in any one of.

[8] The method for producing a carbon fiber reinforced molding material according to any one of [1] to [7], wherein all steps are performed online.

[9] Among the solid content of the mass in the carbon fiber substrate (A2), the proportion of the carbon fibers is less than 80 mass% to 100 mass%, the carbon fiber according to any one of [1] to [8] A method for producing a reinforced molding material.

[10] the first 1a, 1b, in any of the steps of 1c, when processing carbon fiber substrate (A1), carbon fiber substrate thermoplastic resin (C) in fibrous or particulate form (A1) The manufacturing method of the carbon fiber reinforced molding material in any one of [1]-[8] mixed in.

[11] After any one of the steps 4a, 3b, and 3c, the obtained carbon fiber reinforced molding material has a step of cutting to 1 to 30 mm in both the length direction and the width direction. [1] to [10 ] The manufacturing method of the carbon fiber reinforced molding material in any one of.

[12] The method for producing a carbon fiber-reinforced molding material according to any one of [1] to [11], wherein the (meth) acrylic polymer (B) has a cohesive energy density CED of 385 MPa or more.

[13] The (meth) acrylic monomer constituting the (meth) acrylic polymer (B) has an acryloyloxy group or a methacryloyloxy group bonded to hydrogen and / or a primary carbon atom (meth) The manufacturing method of the carbon fiber reinforced molding material in any one of [1]-[12] whose acrylic monomer is 60 mass% or more.

[ 14 ] The carbon fiber reinforced molding according to any one of [1] to [13], wherein the surface oxygen concentration O / C measured by X-ray photoelectron spectroscopy of the carbon fiber is 0.05 to 0.5. Material manufacturing method.

[ 15 ] The thermoplastic resin (C) is a thermoplastic resin comprising at least one selected from polyolefin, polyamide, polycarbonate, polyester, polyphenylene sulfide, polyphenylene ether, and PEEK. [1] to [ 14 ] The manufacturing method of the carbon fiber reinforced molding material in any one of.

According to the method for producing a carbon fiber reinforced molding material of the present invention, it is possible to mold a molded product having excellent mechanical properties such as specific strength and specific rigidity, good dispersibility of carbon fiber, and good uniformity. The carbon fiber reinforced molding material which can be obtained can be obtained efficiently.

It is a schematic diagram of the slurry used in order to make a reinforced fiber base material with a wet method. It is a model figure of the apparatus for manufacturing a reinforced fiber base material (A1) and (A2). It is a model figure of the apparatus for manufacturing a fiber reinforced molding material. It is a model figure of the apparatus for manufacturing a reinforced fiber base material (A1) and (A2) and a fiber reinforced molding material. It is a model figure of the apparatus for manufacturing a reinforced fiber base material (A1) and (A2) and a fiber reinforced molding material. It is a model figure of the apparatus for manufacturing a reinforced fiber base material (A1). It is a model figure of the apparatus for manufacturing a reinforced fiber base material (A1) and (A2) and a fiber reinforced molding material. It is a model figure of the apparatus for manufacturing a reinforced fiber base material (A1) and (A2) and a fiber reinforced molding material.

Hereinafter, preferred embodiments of the present invention will be described. In the present invention, carbon fiber is used as the reinforcing fiber, and the fiber reinforced molding material means a carbon fiber reinforced molding material.

The 1st form of the manufacturing method of the fiber reinforced molding material of this invention is a manufacturing method of the fiber reinforced molding material containing the following 1a process, 2a process, 3a process, and 4a process.
1a: Step of processing a discontinuous reinforcing fiber bundle into a sheet-like reinforcing fiber substrate (A1) 2a: Side chains on 1 to 70 parts by mass of reinforcing fiber substrate (A1) obtained in step 1a Step (3a) for imparting 0.1 to 10 parts by mass of a (meth) acrylic polymer (B) having a hydroxyl group to the (meth) acrylic polymer (B) obtained in Step 2a is provided. Step 4a: obtained in Step 3a, in which fiber reinforced molding material is obtained by combining thermoplastic resin (C) 20 to 98.9% by mass with 1.1 to 80% by mass of reinforced fiber substrate (A2) A step of drawing the obtained fiber-reinforced molding material at a speed of 1 m / min or more.

  Here, the reinforcing fiber bundle means a fiber bundle composed of reinforcing fibers. The number of single fibers constituting the reinforcing fiber bundle is not particularly limited, but is preferably 24,000 or more, more preferably 48,000 or more from the viewpoint of productivity. The upper limit of the number of single fibers is not particularly limited, but is preferably 300,000 or less in consideration of balance with dispersibility and handleability.

  The length of the reinforcing fiber bundle is preferably 1 to 50 mm, and more preferably 3 to 30 mm. If it is less than 1 mm, it may be difficult to efficiently exhibit the reinforcing effect of the reinforcing fiber, and if it exceeds 50 mm, it may be difficult to maintain good dispersion. The length of the reinforcing fiber bundle means the length of the single fiber constituting the reinforcing fiber bundle. The length of the reinforcing fiber bundle in the fiber axis direction is measured with a caliper, or the single fiber is taken out from the reinforcing fiber bundle and observed with a microscope. Can be measured. Moreover, in order to measure the length of the reinforcing fiber in the molding material, the reinforcing fiber can be separated from the fiber-reinforced molding material and measured as follows. A part of the fiber reinforced molding material is cut out, and the thermoplastic resin is sufficiently dissolved with a solvent that dissolves the bound thermoplastic resin. Thereafter, the reinforcing fibers are separated from the thermoplastic resin by a known operation such as filtration. Alternatively, a part of the fiber reinforced molding material is cut out and heated at a temperature of 500 ° C. for 2 hours to burn off the thermoplastic resin and separate the reinforced fibers from the thermoplastic resin. 400 separated reinforcing fibers are randomly extracted, and the length is measured to the unit of 10 μm with an optical microscope or a scanning electron microscope, and the average value is defined as the fiber length.

The reinforcing fibers, specific strength, in terms of higher weight reduction effect specific rigidity, PAN-based carbon fibers, carbon fibers such as pitch-based carbon fibers and rayon-based carbon fiber are needed use. Moreover, it is preferable to use together carbon fiber and glass fiber from the balance of mechanical characteristics and economical efficiency. Moreover, it is preferable to use carbon fiber and an aramid fiber together from the balance of mechanical properties and impact absorbability. Moreover, the carbon fiber which coat | covered metals, such as nickel, copper, and ytterbium, can also be used from a viewpoint of improving the electroconductivity of the molded article obtained.

  Among them, the carbon fiber preferably has a surface oxygen concentration O / C measured by X-ray photoelectron spectroscopy of 0.05 to 0.5, more preferably 0.06 to 0.3, What is 0.07-0.2 is still more preferable. When the surface oxygen concentration O / C is 0.05 or more, the amount of polar functional groups on the surface of the carbon fiber is ensured, and the affinity with the thermoplastic resin is increased, so that stronger adhesion can be obtained. In addition, when the surface oxygen concentration O / C is 0.5 or less, a decrease in strength of the carbon fiber itself due to surface oxidation can be reduced.

The surface oxygen concentration O / C means the ratio of the number of oxygen (O) and carbon (C) atoms on the fiber surface. The procedure for obtaining the surface oxygen concentration O / C by X-ray photoelectron spectroscopy will be described below with an example. First, the carbon fiber from which the sizing agent adhering to the carbon fiber surface is removed with a solvent is cut into 20 mm, spread on a copper sample support base and arranged, and then the inside of the sample chamber is kept at 1 × 10 ⁸ Torr. . A1Kα1 and 2 are used as the X-ray source, and the kinetic energy value (KE) of the main peak of C _1S is adjusted to 1202 cV as a peak correction value associated with charging during measurement. K. E. The C _1S peak area is obtained by drawing a straight base line in the range of 1191 to 1205 eV. K. E. As such, the O _1S peak area is obtained by drawing a straight base line in the range of 947 to 959 eV.

The surface oxygen concentration O / C is calculated from the ratio of the O _1S peak area and the C _1S peak area as an atomic ratio by using a sensitivity correction value unique to the apparatus. When model ES-200 manufactured by Kokusai Electric Inc. is used as the X-ray photoelectron spectroscopy apparatus, the sensitivity correction value can be calculated as 1.74.

  The means for controlling the surface oxygen concentration O / C of the carbon fiber to 0.05 to 0.5 is not particularly limited, and examples include techniques such as electric field oxidation treatment, chemical solution oxidation treatment, and gas phase oxidation treatment. Is done. Of these, electric field oxidation treatment is preferred because it is easy to handle.

  As the electrolytic solution used for the electric field oxidation treatment, aqueous solutions of the following compounds are preferably used. Inorganic acids such as sulfuric acid, nitric acid and hydrochloric acid; inorganic hydroxides such as sodium hydroxide, potassium hydroxide and barium hydroxide; inorganic metal salts such as ammonia, sodium carbonate and sodium hydrogen carbonate; sodium acetate, sodium benzoate and the like Organic salts; organic compounds such as hydrazine. Among these, an inorganic acid is preferable as the electrolytic solution, and sulfuric acid and nitric acid are particularly preferably used. The degree of the electric field treatment can control O / C on the surface of the carbon fiber by setting the amount of electricity flowing in the electric field treatment.

  In the step 1a, when a discontinuous reinforcing fiber bundle is processed into a sheet-like reinforcing fiber base (A1), a dry method or a wet method can be used. In order to obtain a reinforcing fiber base material (A1) that is isotropic and has high mechanical properties, it is preferable that the reinforcing fiber bundle is highly dispersed to obtain a base material in which the reinforcing fibers are uniformly dispersed.

  When the step 1a is performed by a dry method, the reinforcing fiber bundle is dispersed in the gas phase, and the dispersed reinforcing fiber bundle is deposited, whereby the sheet-like reinforcing fiber substrate (A1) can be obtained.

  Dispersion of reinforcing fiber bundles in the gas phase is performed by opening the reinforcing fiber bundles in a non-contact manner and depositing the opened reinforcing fiber bundles (non-contact method), and contacting the reinforcing fiber bundles. There is a method (contact type method) in which the fiber is opened by a formula and the opened reinforcing fiber bundles are deposited.

  The non-contact method is a method of opening a fiber without bringing a solid or a fiber opening device into contact with the reinforcing fiber bundle. For example, a method of spraying a gas such as air or an inert gas onto the reinforcing fiber bundle, particularly a method of pressurizing and spraying air advantageous in terms of cost is preferable.

  In the method using an air flow, the conditions for applying the air flow to the reinforcing fiber bundle are not particularly limited. For example, pressurized air (usually an air flow that applies a pressure of 0.1 MPa to 10 MPa, preferably 0.5 MPa to 5 MPa) is applied until the reinforcing fiber bundle is opened. In the method using an air flow, an apparatus that can be used is not particularly limited, and examples thereof include a container that includes an air tube and that can suck air and can contain a reinforcing fiber bundle. By using such a container, it is possible to open and deposit the reinforcing fiber bundle in one container.

  The contact method is a method in which a solid or a fiber opening device is brought into physical contact with a reinforcing fiber bundle for fiber opening. Examples of the contact method include carding, needle punching and roller opening. Of these, carding or needle punch is preferable, and carding is more preferable. The conditions for carrying out the contact method are not particularly limited, and conditions for opening the reinforcing fiber bundle can be determined as appropriate.

  When the step 1a is performed by a wet method, the reinforcing fiber bundle can be dispersed in water, and the resulting slurry can be made to obtain a sheet-like reinforcing fiber substrate (A1).

  As water (dispersion liquid) for dispersing the reinforcing fiber bundle, water such as distilled water and purified water can be used in addition to normal tap water. A surfactant or a thickener can be mixed with water as necessary. Surfactants are classified into a cation type, an anion type, a nonionic type and various amphoteric types. Among these, nonionic surfactants are preferably used, and polyoxyethylene lauryl ether is more preferably used. . As the thickener, polyacrylamide, polyethylene oxide, starch or the like is preferably used. The concentration when the surfactant or thickener is mixed with water is preferably 0.0001% by mass or more and 0.1% by mass or less, more preferably 0.0003% by mass or more and 0.05% by mass or less.

  Slurry refers to a suspension in which solid components are dispersed. The solid component concentration in the slurry is preferably 0.001% by mass or more and 1% by mass or less, and more preferably 0.01% by mass or more and 0.5% by mass or less. Here, the solid component concentration in the slurry means the mass content of the reinforcing fiber in the slurry when the slurry does not contain any component other than the reinforcing fiber as the solid component, and other than the reinforcing fiber in the slurry. Furthermore, when a solid component such as fibers or particles of a thermoplastic resin is included, it means the mass content in the slurry of all the solid components. When the solid component concentration in the slurry is 0.01% by mass or more and 1% by mass or less, a uniformly dispersed slurry can be obtained in a short time, and papermaking can be performed efficiently. When the reinforcing fiber bundle is dispersed in water (dispersion), stirring is performed as necessary.

  The slurry can be made by sucking water from the slurry. Slurry papermaking can be performed according to a so-called papermaking method. For example, the slurry is poured into a tank having a papermaking surface at the bottom and capable of sucking water from the bottom, and sucks the water. As said tank, the Kumagaya Riki Kogyo Co., Ltd. make, No. 2553-I (trade name), and a tank provided with a mesh conveyor having a papermaking surface with a width of 200 mm at the bottom. In this way, the reinforcing fiber substrate (A1) is obtained.

  In order to produce a papermaking body in which solid components are uniformly blended, it is common to dilute the slurry concentration before supplying the raw material slurry to the papermaking process (see, for example, JP-A-2006-104608). . Specifically, in order to maintain the dispersibility of the reinforcing fibers in the slurry, it has been proposed to first create a slurry having a high reinforcing fiber concentration and then dilute it to obtain a slurry having a low reinforcing fiber concentration. However, taking two steps complicates the work, and in the case of reinforcing fibers having a low affinity for the dispersion medium of the slurry, it is very difficult to produce a slurry having a high reinforcing fiber concentration.

  Then, when manufacturing the reinforced fiber base material (A1) by a wet method, manufacturing with the following method is more preferable. That is, the step (i) of introducing a discontinuous reinforcing fiber bundle into the dispersion medium, the step (ii) of preparing a slurry in which the reinforcing fibers constituting the reinforcing fiber bundle are dispersed in the dispersion medium, and the slurry Removing the dispersion medium to obtain the reinforcing fiber substrate (A1) (iii), wherein the mass content of the reinforcing fibers in the slurry prepared in the step (ii) is C1, and the step (iii) This is a method for producing a reinforcing fiber substrate (A1) in which C1 / C2 is in the range of 0.8 to 1.2 when the mass content of reinforcing fibers in the slurry at the start is C2. According to the method for producing the reinforcing fiber substrate (A1), the reinforcing fiber base material (A1) can be applied to a reinforcing fiber having a low affinity for a dispersion medium at the time of slurry adjustment, retains the fiber dispersibility of the reinforcing fiber at the time of making paper, Is preferable because a reinforcing fiber substrate (A1) having excellent mechanical properties of the molded product can be obtained in a short time. The preferable range of C1 / C2 is 0.8 or more and 1.2 or less, but more preferably 0.9 or more and 1.1 or less.

  The time required for step (ii) is preferably within 10 minutes, more preferably within 5 minutes, and even more preferably within 3 minutes. If it exceeds 10 minutes, depending on the type of reinforcing fiber, the reinforcing fiber dispersed in the slurry may reaggregate. Although the minimum of the time required for process (ii) is not specifically limited, Usually, it is 1 minute or more.

Slurry flow rate to the step (iii), 0.001 m ³ / is preferably sec or higher 0.1m is ³ / sec or less, more that 0.005 m ³ / sec or more 0.05 m ³ / sec or less preferable. If the flow rate is less than 0.001 m ³ / sec, the supply amount is small and the process takes time, and therefore the productivity may be deteriorated. If the flow rate exceeds 0.1 m ³ / sec, the flow rate of the slurry is high. Tends to be applied and the dispersion state may be insufficient.

In the steps (ii) to (iii), it is preferable that the fiber density parameter nL ³ is made in the range of (0 <) nL ³ <L / D. Here, each parameter is as follows.
n: Number of reinforcing fibers contained per unit volume of slurry L: Length of reinforcing fibers D: Diameter of reinforcing fibers.

FIG. 1 shows a schematic diagram of a slurry containing reinforcing fibers 1 in a dispersion medium 2. In Doi, M .. and Edwards, SF, The Theory of Polymer Dynamics 324 (1986), the fiber concentration parameter nL ³ is dilute when nL ³ <1, and is semi-lean when 1 <nL ³ <L / D. The state is described. When the fiber concentration parameter nL ³ is less than L / D, the reinforcing fibers 1 dispersed in the slurry are difficult to mechanically interfere with each other. Therefore, reaggregation of the reinforcing fibers 1 is suppressed, and the reinforcing fibers 1 in the slurry. It is preferable for increasing the dispersibility of the resin. The lower the concentration of the reinforcing fiber 1, the higher the dispersibility of the reinforcing fiber 1, which is preferable. However, when it is desired to secure the basis weight and thickness of the resulting reinforcing fiber base (A1), the reinforcing fiber base (A1) In order to increase productivity, it is advantageous that the concentration of the reinforcing fiber 1 is high. Therefore, it is preferable to make paper with a reinforcing fiber concentration of 1 <nL ³ <L / D, which is a quasi-dilute state.

In addition, the water content of the obtained reinforcing fiber base (A1) is determined by dehydration or (meth) acrylic polymer (B) before applying (meth) acrylic polymer (B) in the step (2a). It is preferably adjusted to 10% by mass or less, more preferably 5% by mass or less by the drying step. Thereby, the time required for the step 2a can be shortened and the prepreg can be obtained in a short time. The dispersion of the reinforcing fibers is hardly inhibited, the viewpoint of dispersing the reinforcing fibers satisfactorily, and the reinforcing fiber base (A1) is heated. From the viewpoint of efficiently producing a reinforcing effect when combined with a plastic resin, the proportion of reinforcing fibers in the reinforcing fiber base (A1) is 80% by mass or more and 100% by mass or less. Preferably, it is 90 mass% or more and 100 mass% or less. In this case, a ratio of impregnating the reinforcing fiber base material with the thermoplastic resin in a later step increases.

  On the other hand, from the viewpoint of easily impregnating the reinforcing fiber base (A1) with the thermoplastic resin, when the reinforcing fiber base (A1) is produced, the thermoplastic resin is in a fibrous or particulate form. It is preferable to mix in the reinforcing fiber base (A1). As a result, since the thermoplastic resin is arranged inside the reinforcing fiber base (A1), the reinforcing fiber base (A1) is easily impregnated with the thermoplastic resin in the step of heating and melting the composite. it can. In this case, the thermoplastic resin is preliminarily combined with the reinforcing fiber base (A1). In the dry method, for example, the reinforcing fiber bundle and the fibrous thermoplastic resin can be mixed and carded in the step 1a. The wet method can be carried out, for example, by mixing the reinforcing fiber bundle and the fibrous or particulate thermoplastic resin in the step 1a.

  In order to make the fiber reinforced molding material a molding material used for injection molding, the fiber reinforced molding material obtained in any of the length direction and the width direction is 1 to 4 after any of the steps 4a, 3b, 3c. You may provide the process cut to 30 mm. In consideration of the handling property of the molding material (such as supply stability to an injection molding machine) and the mechanical properties of the obtained molded product, it is preferable to cut the sheet in the length direction and the width direction in 3 to 10 mm.

The basis weight of the reinforcing fiber base (A1) is preferably 10 g / m ² or more and 500 g / m ² or less, and more preferably 50 g / m ² or more and 300 g / m ² or less. If the weight per unit area is less than 10 g / m ² , there is a risk of problems in handling such as tearing of the substrate. If the basis weight exceeds 500 g / m ² , it may take a long time to dry the substrate in the wet method, or the web may become thick in the dry method, and the handling property may be difficult in the subsequent process.

  In step 2a, 0.1 to 10 parts by weight of (meth) acrylic polymer (B) having a hydroxyl group in the side chain is added to 1 to 70 parts by weight of the reinforcing fiber base (A1) obtained in step 1a. To do. The (meth) acrylic polymer (B) is important for enhancing the handleability of the reinforcing fiber substrate (A2) in the process and for interfacial adhesion between the reinforcing fiber and the thermoplastic resin. When the (meth) acrylic polymer (B) is less than 0.1 parts by mass, it becomes difficult to take up the reinforcing fiber base (A2), and the production efficiency of the fiber-reinforced molding material is deteriorated. Moreover, when it exceeds 10 mass parts, it will be inferior to the interface adhesiveness of a reinforced fiber and a thermoplastic resin.

  Since the (meth) acrylic polymer (B) has a hydroxyl group, an effect of increasing the interaction between the (meth) acrylic polymers (B) and improving the handleability of the reinforcing fiber base (A2) is seen. . Moreover, it also has an effect of increasing the interfacial adhesion between the reinforcing fiber and the thermoplastic resin.

  As the (meth) acrylic monomer unit having a hydroxyl group forming a (meth) acrylic polymer having a hydroxyl group in the side chain, 2-hydroxyethyl acrylate, 2-hydroxypropyl acrylate, 4-hydroxy acrylate Butyl, 2-hydroxyethyl methacrylate, 2-hydroxypropyl methacrylate, 4-hydroxybutyl methacrylate, glycerin monomethacrylate, glyceryl-1-methacryloyloxyethyl urethane, 3,4-dihydroxybutyl-1-methacryloyloxyethyl urethane, α-hydroxymethyl acrylate, α-hydroxyethyl acrylate, diethylene glycol monoacrylate, triethylene glycol monoacrylate, polyethylene glycol noacrylate, dipropylene glycol mono Acrylate, tripropylene glycol monoacrylate, polypropylene glycol monoacrylate, dibutanediol monoacrylate, tributanediol monoacrylate, polytetramethylene glycol monoacrylate, diethylene glycol monomethacrylate, triethylene glycol monomethacrylate, polyethylene glycol monomethacrylate, dipropylene glycol Examples include hydroxyl group-containing (meth) acrylic monomer units such as monomethacrylate, tripropylene glycol monomethacrylate, polypropylene glycol monomethacrylate, dibutanediol monomethacrylate, tributanediol monomethacrylate, and polytetramethylene glycol monomethacrylate. Of these, 2-hydroxyethyl acrylate and 2-hydroxyethyl methacrylate, which are easily available, are preferred. These monomers may be used alone or in combination.

  Other (meth) acrylic monomer units that form a (meth) acrylic polymer having a hydroxyl group in the side chain include acrylic acid, methacrylic acid, maleic acid, maleic anhydride, itaconic acid, β-carboxyethyl Carboxyl group-containing (meth) acrylic monomer such as acrylate; methyl acrylate, ethyl acrylate, n-butyl acrylate, isobutyl acrylate, t-butyl acrylate, cyclohexyl acrylate, 2-ethylhexyl acrylate, acrylic Lauryl acid, stearyl acrylate, benzyl acrylate, isobornyl acrylate, methyl methacrylate, ethyl methacrylate, n-butyl methacrylate, t-butyl methacrylate, isobutyl methacrylate, cyclohexyl methacrylate, 2-ethylhexyl methacrylate, (Meth) acrylic acid (fluoro) alkyl esters such as lauryl tacrylate, stearyl methacrylate, benzyl methacrylate, isobornyl methacrylate, trifluoroethyl methacrylate; dicyclopentenyl acrylate, dicyclopentenyloxyethyl acrylate, dicyclopentenyl methacrylate (Meth) acrylic monomer units having a dicyclopentenyl group such as dicyclopentenyloxyethyl methacrylate; amino group-containing (meth) acrylic such as N, N-dimethylaminoethyl methacrylate and N, N-diethylaminoethyl methacrylate Monomer units; glycidyl acrylate, methyl glycidyl acrylate, glycidyl methacrylate, methyl glycidyl methacrylate, vinyl benzyl glycidyl Epoxy group-containing (meth) acrylic monomer units such as ether, 3,4-epoxycyclohexylmethyl methacrylate; acrylamide, N, N-dimethylacrylamide, N, N-diethylacrylamide, N-isopropylacrylamide, N, N- Amides such as dimethylaminopropylacrylamide, N, N-diethylaminopropylacrylamide, N-methylolacrylamide, N- (2-hydroxyethyl) acrylamide, N- (3-hydroxypropylacrylamide), N- (4-hydroxybutyl) acrylamide Group-containing (meth) acrylic monomer units; urea group-containing (meth) acrylic units such as N- (2-methacryloyloxyethyl) ethyleneurea and N- (2-methacrylamidoethyl) ethyleneurea Body unit; (meth) acrylic monomer unit having methoxy group or ethoxy group such as 2-methoxyethyl acrylate, 2-ethoxyethyl acrylate, 2-methoxyethyl methacrylate, 2-ethoxyethyl methacrylate, etc .; N -Carbonyl group-containing (meth) acrylic monomer units such as vinyl-2-pyrrolidone and diacetone acrylamide; zinc acrylate, zinc methacrylate, hybrid polyester acrylate oligomer "Sartomer (registered trademark) CN-2402" (Sartomer ( Co., Ltd. Zn-containing acrylic oligomer), hybrid polyurethane oligomer “Sartomer (registered trademark) 2405” (Sartomer Co., Ltd. Zn-containing acrylic oligomer), and the like in metal molecules (Zn, Al, Ca, Mg, Zr) , Cu, etc.) Nomar, such oligomers are exemplified. These may be used alone or in combination of two or more.

  The cohesive energy density CED of the (meth) acrylic copolymer having a hydroxyl group in the side chain is preferably 385 to 500 MPa, more preferably 395 to 450 MPa, and still more preferably 405 to 420 MPa. When the cohesive energy density CED is 385 MPa or more, there is a tendency that good permeability, wettability and affinity to the reinforcing fiber substrate (A1) and the thermoplastic resin are obtained and good interfacial adhesion is exhibited. If the cohesive energy density is too high or too low, the affinity balance is lost and the interfacial adhesion is reduced.

Here, a method for calculating the cohesive energy density CED (unit: MPa) of the (meth) acrylic copolymer will be described. The type of (meth) acrylic monomer unit contained in the (meth) acrylic polymer is m, and each (meth) acrylic monomer unit is (meth) acrylic monomer unit (n) ( When n is an integer from 1 to m, CED is calculated by the following formula. However, ΣP (n) = 1.
CED = 1.15 * [Sigma] {P (n) * CE (n)} / [Sigma] (P (n) * M (n)) (n = 1 to m)
CE (n) means the cohesive energy calculated from the chemical structure CS (n) of the (meth) acrylic monomer unit (n). Similarly, M (n) is the molecular weight of the (meth) acrylic monomer unit (n), and P (n) is the (meth) acrylic monomer unit (n in the (meth) acrylic polymer. ) Mole fraction. Here, CS (n) is the chemical structure of the (meth) acrylic monomer unit (n), that is, the chemical structure in which the C═C double bond of the monomer is opened. The coefficient 1.15 represents the specific gravity of the (meth) acrylic monomer unit.

CE (n) is calculated by CE (n) = ΣEcoh (n). Here, ΣEcoh (n) constitutes the chemical structure CS (n). For example, the cohesive energy Ecoh (n) of atomic groups such as —CH ₃ , —CH ₂ —,> C <, —COOH, —OH, etc. Represents the sum.

  Here, the cohesive energy of each atomic group is as follows: (1) RFFedors: “A Method for Estimating Both the Solubility Parameters and Molar Volumes of Liquids”, Polm. Eng. Sci., 14 (2) .147- 154 (1974) and reference: (2) “SP value basics / applications and calculation methods” (Information Organization Co., Ltd.), 6th edition, p69, 2008, the atoms proposed by RFFedors The cluster cohesive energy Ecoh (J / mol) was used.

  As an example, Table 1 shows an example of calculating the cohesive energy of a chemical structure in which methacrylic acid, 2-hydroxyethyl methacrylate, methyl methacrylate and the like are radically polymerized.

  In Table 1, MAA represents a methacrylic acid unit, HEMA represents a 2-hydroxyethyl methacrylate unit, 4HBMA represents a 4-hydroxybutyl methacrylate unit, MMA represents a methyl methacrylate unit, and BMA represents a methacrylate n. -Represents a butyl unit, EHMA represents a 2-ethylhexyl methacrylate unit. These abbreviations are also used in the following description.

Taking MAA as an example, a method for calculating the cohesive energy CE (n) of the (meth) acrylic monomer unit (n) will be described. The column of Ecoh (J / mol) of the atomic group shows the cohesive energy (J / mol) of each atomic group such as —CH ₃ —, and the left frame of the MAA column has a chemical structure obtained by radical polymerization of MAA. The number of atomic groups is shown, and the product in the right frame shows the product of the cohesive energy (J / mol) of the atomic group and the number of atomic groups. The total sum of the MAA column and the right frame is the MAA cohesive energy CE (n).

  A method for calculating the cohesive energy density CED will be described by taking as an example a (meth) acrylic polymer using MAA, HEMA, MMA and BMA as the (meth) acrylic monomer unit.

  Here, in this example, MMA / BMA / MAA / HEMA = 35/54/1/10 (= 100) (mass%) = 0.427 / 0.464 / 0.014 / 0.095 (= 1. 000) (molar fraction).

  The molecular weight of the MMA monomer unit structure (with C = C double bond open) is 100, the cohesive energy is 33830 J / mol, the molecular weight of the monomer unit of BMA is 142, the cohesive energy is 48650 J / mol, MAA The molecular weight of the monomer unit is 86, the aggregation energy is 38750 J / mol, the molecular weight of the monomer unit of HEMA is 130, and the aggregation energy is 60850 J / mol. Therefore, the aggregation energy density CED of the (meth) acrylic polymer is = 1.15 x (0.427 x 33830 + 0.464 x 48650 + 0.014 x 38750 + 0.095 x 60850) / (0.427 x 100 + 0.464 x 142 + 0.014 x 86 + 0.095 x 130) = 408 MPa.

  In the (meth) acrylic monomer unit having a hydroxyl group and the other (meth) acrylic monomer units, the acryloyloxy group or the methacryloyloxy group is bonded to hydrogen and / or a primary carbon atom ( Of all the (meth) acrylic monomer units constituting the (meth) acrylic polymer, an acryloyloxy group or a methacryloyloxy group is bonded to hydrogen and / or a primary carbon atom (meth) acrylic monomer It is preferable that a body unit is 60 mass% or more. More preferably, it is 75 mass% or more, More preferably, it is 90 mass% or more. By setting it as this range, the (meth) acrylic polymer (B) becomes relatively flexible, the handling property of the reinforcing fiber base (A2) can be improved, and the (meth) acrylic polymer By being relatively flexible, the interface part, that is, the adhesive part can be kept flexible in the adhesion between the reinforcing fiber and the (meth) acrylic polymer and between the (meth) acrylic polymer and the thermoplastic resin. Can increase the sex.

  The application of the (meth) acrylic polymer (B) to the reinforcing fiber base (A1) is preferably performed using an aqueous solution, emulsion or suspension containing the (meth) acrylic polymer (B). The aqueous solution means a solution in which the (meth) acrylic polymer (B) is almost completely dissolved in water. The emulsion means a state in which a liquid containing a (meth) acrylic polymer is dispersed by forming fine particles in a liquid as a dispersion medium. Suspension means a state in which a solid (meth) acrylic polymer is suspended in water. The component particle sizes in the liquid are in the order of aqueous solution <emulsion <suspension. The method for applying the (meth) acrylic polymer to the reinforcing fiber base (A1) is not particularly limited. For example, the reinforcing fiber base (A1) is applied to an aqueous solution, emulsion or suspension containing the (meth) acrylic polymer. , An aqueous solution containing a (meth) acrylic polymer, an emulsion or a suspension can be used for showering the reinforcing fiber substrate (A1). After the application, it is preferable to remove the excess aqueous solution, emulsion, or suspension by, for example, a method of removing by suction or a method of absorbing into an absorbent material such as absorbent paper.

  Furthermore, in this case, in the step 2a, the reinforcing fiber base (A1) is preferably heated after the application of the (meth) acrylic polymer (B). This removes moisture contained in the reinforcing fiber base (A1) after the (meth) acrylic polymer (B) is applied, shortens the time required for the step 3a, and shortens the fiber-reinforced molding material. Can get in time. The heating temperature can be appropriately set and is preferably 100 ° C. or higher and 300 ° C. or lower, and more preferably 120 ° C. or higher and 250 ° C. or lower.

  The reinforcing fiber base (A2) provided with the (meth) acrylic polymer (B) obtained in the step 2a is preferably taken up in order to produce a large amount in a short time. At that time, it is preferable that the tensile strength is 1 N / cm or more so that the reinforcing fiber base (A2) does not wrinkle or sag. The tensile strength is more preferably 3 N / cm or more, and further preferably 5 N / cm or more. The tensile strength that can be applied to the reinforcing fiber base (A2) can be controlled by adjusting the type and amount of the (meth) acrylic polymer (B). Can do. In addition, when the tensile strength applied is less than 1 N / cm, the reinforcing fiber base (A2) is easily broken, and from the viewpoint of handling of the reinforcing fiber base (A2), the tensile strength is 1 N / cm. It is preferable that it is cm or more. The upper limit of the tensile strength is not particularly limited, but if it is 100 N / cm, the handleability of the reinforcing fiber substrate (A2) is sufficiently satisfactory.

  In step 3a, the reinforcing fiber substrate (A2) provided with the (meth) acrylic polymer (B) obtained in step 2a is impregnated with the thermoplastic resin (C), and the reinforcing fiber substrate (A2). And a thermoplastic resin are combined to obtain a fiber-reinforced molding material. Here, as the thermoplastic resin (C), for example, “polyethylene terephthalate (PET), polybutylene terephthalate (PBT), polytrimethylene terephthalate (PTT), polyethylene naphthalate (PEN), liquid crystal polyester, and the like; polyethylene Polyolefins such as (PE), polypropylene (PP), and polybutylene; polyoxymethylene (POM); polyamide (PA); polyarylene sulfides such as polyphenylene sulfide (PPS); polyketone (PK), polyetherketone (PEK), Polyetheretherketone (PEEK), Polyetherketoneketone (PEKK), Polyethernitrile (PEN); Fluorine resin such as polytetrafluoroethylene; Liquid crystal polymer (LCP) " Crystalline resin; “Styrenic resin, polycarbonate (PC), polymethyl methacrylate (PMMA), polyvinyl chloride (PVC), polyphenylene ether (PPE), polyimide (PI), polyamideimide (PAI), polyetherimide (PEI) ), Polysulfone (PSU), polyethersulfone, polyarylate (PAR) ", etc .; phenolic resin, phenoxy resin; polystyrene elastomer, polyolefin elastomer, polyurethane elastomer, polyester elastomer, polyamide -Type elastomers, polybutadiene-based elastomers, polyisoprene-based elastomers, fluororesins, and various thermoplastic elastomers such as acrylonitrile-based elastomers; copolymers and modifications thereof At least one thermoplastic resin is preferably used selected from the like. Among these, polyolefin is preferable from the viewpoint of light weight of the obtained molded product. From the viewpoint of strength, polyamide is preferred. From the viewpoint of surface appearance, an amorphous resin such as polycarbonate or styrene resin is preferred. From the viewpoint of heat resistance, polyarylene sulfide is preferred. From the viewpoint of continuous use temperature, polyether ether ketone is preferred. From the viewpoint of chemical resistance, a fluororesin is preferred. As the thermoplastic resin (C), a thermoplastic resin composition containing a plurality of types of these thermoplastic resins may be used as long as the object of the present invention is not impaired.

  The content of the reinforcing fiber, the (meth) acrylic polymer (B) and the thermoplastic resin (C) with respect to the fiber-reinforced molding material is 1 to 70% by mass of the reinforcing fiber, and the (meth) acrylic polymer (B). 0.1-10 mass% and a thermoplastic resin (C) are 20-98.9 mass%. By setting it as this range, it is easy to obtain a molding material that can efficiently reinforce reinforcing fibers. More preferably, the reinforcing fiber is 10 to 60% by mass, the (meth) acrylic polymer (B) is 0.5 to 10% by mass, and the thermoplastic resin is 30 to 89.5% by mass. More preferably, the reinforcing fiber is 20 to 60% by mass, the (meth) acrylic polymer (B) is 1 to 8% by mass, and the thermoplastic resin is 32 to 79% by mass.

  The composite of the thermoplastic resin (C) and the reinforcing fiber base (A2) to which the (meth) acrylic polymer (B) is applied is obtained by converting the thermoplastic resin (C) into the reinforcing fiber base (A2). This can be done by contacting them. The form of the thermoplastic resin (C) in this case is not particularly limited, but is preferably at least one form selected from, for example, a fabric, a nonwoven fabric, and a film. The method of contact is not particularly limited, but two thermoplastic fabrics, non-woven fabrics or films are prepared and placed on the upper and lower surfaces of the reinforcing fiber substrate (A2) to which the (meth) acrylic polymer (B) is applied. The method of doing is illustrated.

  The composite of the thermoplastic resin (C) and the reinforcing fiber base (A2) provided with the (meth) acrylic polymer (B) is preferably performed by pressurization and / or heating. More preferably, both heating and heating are performed simultaneously. The pressurization condition is preferably 0.01 MPa or more and 10 MPa or less, and more preferably 0.05 MPa or more and 5 MPa or less. The heating condition is preferably a temperature at which the thermoplastic resin to be used can be melted or flowed, and is preferably 50 ° C. or higher and 400 ° C. or lower, more preferably 80 ° C. or higher and 350 ° C. or lower in the temperature range. The pressurization and / or heating can be performed in a state where the thermoplastic resin (C) is brought into contact with the reinforcing fiber base (A2) to which the (meth) acrylic polymer (B) is applied. For example, two fabrics, nonwoven fabrics or films of thermoplastic resin (C) are prepared and placed on the upper and lower surfaces of the reinforcing fiber substrate (A2) to which the (meth) acrylic polymer (B) is applied. Examples thereof include a method of heating and / or heating (a method of sandwiching with a double belt press device).

  The present invention further includes a step 4a in addition to the steps 1a to 3a. The 4a step is a step of taking up the fiber reinforced molding material obtained in the 3a step at a speed of 1 m / min or more. The reinforcing fiber base (A2) is heated by combining the reinforcing fiber base (A2) to which the (meth) acrylic polymer (B) having a hydroxyl group in the side chain is provided and the thermoplastic resin (C). It will be reinforced more strongly by the plastic resin (C), and the fiber-reinforced molding material can be taken up at the above speed. The fiber-reinforced molding material can be taken up on a roll. The take-up speed is preferably 3 m / min, more preferably 5 m / min, still more preferably 10 m / min or more. The upper limit of the take-up speed is preferably 100 m / min or less, more preferably 30 m / min or less.

  Since the fiber-reinforced molding material can be obtained in a short time, it is more preferable that all of the steps 1a to 4a are performed online. On-line is a process in which each step is continuously performed as a series of flows, and is the opposite of off-line in which each step is performed independently.

Furthermore, in the step 1a, it is preferable that the dispersion medium and the reinforcing fiber bundle are continuously added and the steps (i) to (iii) are continuously performed. Thereby, more reinforcing fiber base materials (A1) can be obtained in a shorter time. In addition, if a large amount of slurry is added at once, a part of the slurry may take a long time to be paper-made, resulting in a poor dispersion state. However, from step (i) to step (iii) By carrying out continuously, it is possible to feed the slurry little by little, and to make paper efficiently and while maintaining the dispersed state. Here, “continuously” means that the raw materials are intermittently or continuously added in the step (i), and the steps (ii) to (iii) are subsequently performed. In other words, in a series of steps, it means a state in which the supply of the raw material of the dispersed slurry and the slurry supply to the subsequent step are continued, and is a process considering mass production. Examples of the method of continuously charging include a method of charging at a constant speed and a method of charging a substantially constant amount at a predetermined interval. The conditions for charging at a constant speed are a speed of 1 × 10 ³ g / min to 1 × 10 ⁷ g / min for the dispersion medium, and a speed of 0.1 g / min to 1 × 10 ⁵ g / min for the reinforcing fiber bundle. The conditions to be input are exemplified. The conditions for introducing a substantially constant amount at a predetermined interval are 1 × 10 ³ g or more and 1 × 10 ⁷ g or less for the dispersion medium every 1 to 5 minutes, and 0.1 g or more and 1 × 10 ⁵ g for the reinforcing fiber bundle. The following conditions are exemplified.

The 2nd form of the manufacturing method of the fiber reinforced molding material of this invention is a manufacturing method of the fiber reinforced molding material containing the following 1b process, 2b process, and 3b process.
1b: A sheet of a discontinuous reinforcing fiber bundle in which 0.1 to 10 parts by mass of a (meth) acrylic polymer (B) having a hydroxyl group in a side chain is attached to 1 to 70 parts by mass of the reinforcing fiber bundle. Step 2b to process the reinforcing fiber substrate (A2): 1.1 to 80% by mass of the reinforcing fiber substrate (A2) to which the (meth) acrylic polymer obtained in the step 1b was applied, and heat Step of obtaining a fiber-reinforced molding material by compounding 20 to 98.9% by mass of the plastic resin (C) 3b: A step of drawing the fiber-reinforced molding material obtained in the step 2b at a speed of 1 m / min or more.

  The part different from the first embodiment is a part using a reinforcing fiber bundle to which the (meth) acrylic polymer (B) has already been applied in the step 1b. Whether the reinforcing fiber bundle to which the (meth) acrylic polymer (B) has already been applied is specifically immersed in an aqueous solution, emulsion or suspension of the (meth) acrylic polymer (B). Alternatively, the reinforcing fiber bundle can be prepared by impregnating them with a shower type, curtain coat type or the like and then drying.

  Steps 2b and 3b are the same as steps 3a and 4a of the first embodiment, respectively.

The 3rd form of the manufacturing method of the fiber reinforced molding material of this invention is a manufacturing method of the fiber reinforced molding material containing the following 1c process, 2c process, and 3c process.
1c: The discontinuous reinforcing fiber bundle is processed into a sheet-like reinforcing fiber base (A1), and at the same time, the (meth) acrylic polymer (B) having a hydroxyl group in the side chain is added to the reinforcing fiber base (A1). Step 2c for obtaining a reinforcing fiber substrate (A2) to which 0.1 to 10 parts by mass of the reinforcing fiber substrate (A1) is added to 1 to 70 parts by mass to which a (meth) acrylic polymer is added. : 1.1 to 80% by mass of the reinforcing fiber base (A2) to which the (meth) acrylic polymer (B) obtained in the step 1c was applied, and 20 to 98.9 thermoplastic resin (C). Step 3c for obtaining a fiber-reinforced molding material by compounding mass%: Step for drawing the fiber-reinforced molding material obtained in step 2c at a speed of 1 m / min or more.

  The part different from the first embodiment is a part that, in the step 1c, processes the discontinuous reinforcing fiber bundle into a sheet-like reinforcing fiber base (A1) and simultaneously gives the (meth) acrylic polymer (B). is there. Specifically, when the step 1c is performed by a dry method, an aqueous solution of (meth) acrylic polymer (B) is simultaneously used when the reinforcing fiber bundle is opened by blowing a gas such as air or an inert gas. In addition, when the emulsion or suspension is applied by spraying or spraying on the reinforcing fiber bundle, or when the reinforcing fiber bundle is opened by a contact method such as carding, needle punching, roller opening, etc. ) A method of applying an aqueous solution, emulsion or suspension of the acrylic polymer (B) by dipping, coating or spraying the reinforcing fiber bundle is applicable. When the step 1c is performed by a wet method, the (meth) acrylic polymer (B) is introduced into a dispersion tank in which the reinforcing fiber bundle is dispersed, and the reinforcing fiber bundle is dispersed to reinforce the reinforcing fiber substrate (A1). At the same time, a method of applying the (meth) acrylic polymer (B) to the reinforcing fiber base (A1) can be applied.

  Step 2c and step 3c are the same as step 3a and step 4a of the first embodiment, respectively.

  In the first embodiment, since the (meth) acrylic polymer (B) is applied in a subsequent process, the (meth) acrylic polymer (B) is applied in advance to the reinforcing fiber bundle, and the second is concentrated. It becomes easier to disperse the reinforcing fiber bundle than the form. Similarly, in the first embodiment, the reinforcing fiber bundle is processed into the sheet-like reinforcing fiber base material (A1), and at the same time, the reinforcing fiber is provided as compared with the third embodiment in which the (meth) acrylic polymer (B) is applied. The bundle is easily dispersed. For example, in the wet method, a large amount of (meth) acrylic polymer (B) is charged into the dispersion tank in the third embodiment, whereas in the first embodiment, the (meth) acrylic polymer (B) is introduced into the dispersion tank. ), It is possible to facilitate dispersion of the reinforcing fiber bundle. Therefore, the first form is most preferable.

  The molded product obtained by using the fiber-reinforced molding material obtained in the present invention can be used for various applications such as electrical / electronic equipment parts; civil engineering / architectural parts; automobile / motorcycle parts; aircraft parts. Among them, it is preferably used for electronic equipment parts and structural parts for automobiles.

  Hereinafter, the present invention will be described in more detail with reference to examples. In addition, the raw material used for the Example is as follows.

(Raw material 1) Reinforcing fiber bundle A1 (PAN-based carbon fiber)
The reinforcing fiber bundle A1 was manufactured as follows.

  Using a copolymer composed of 99.4 mol% of acrylonitrile (AN) and 0.6 mol% of methacrylic acid, an acrylic fiber bundle having a single fiber denier 1d and a filament number of 24,000 was obtained by a dry and wet spinning method. The obtained acrylic fiber bundle was heated at a draw ratio of 1.05 in air at a temperature of 240 to 280 ° C. to convert to a flameproof fiber. Next, the rate of temperature increase was set to 200 ° C./min, and after 10% stretching in a temperature range of 300 to 900 ° C. in a nitrogen atmosphere, the temperature was increased to 1,300 ° C. and fired to obtain a carbon fiber bundle. It was. After performing an electrolytic surface treatment of 3 coulombs per gram of carbon fiber with an aqueous solution containing sulfuric acid as an electrolyte for this carbon fiber bundle, further applying a sizing agent by an immersion method, drying in heated air at a temperature of 120 ° C., Reinforcing fiber bundle A1 (PAN-based carbon fiber) was obtained. The physical properties of the reinforcing fiber bundle A1 are shown below.

Total number of filaments: 24,000 Single fiber diameter: 7 μm
Mass per unit length: 0.8 g / m
Specific gravity: 1.8 g / cm ³
Tensile strength: 4.2 GPa
Tensile modulus: 230 GPa
O / C: 0.10
Sizing agent type: polyoxyethylene oleyl ether Sizing agent adhesion amount (Note 4): 1.5% by mass.

(Raw material 2) Reinforcing fiber bundle A2 (PAN-based carbon fiber)
The reinforcing fiber bundle A2 was manufactured as follows.

  Using a copolymer composed of 99.4 mol% of acrylonitrile (AN) and 0.6 mol% of methacrylic acid, an acrylic fiber bundle having a single fiber denier 1d and a filament number of 12,000 was obtained by a dry and wet spinning method. The obtained acrylic fiber bundle was heated at a draw ratio of 1.05 in air at a temperature of 240 to 280 ° C. to convert to a flameproof fiber. Next, the rate of temperature increase was set to 200 ° C./min, and after 10% stretching in a temperature range of 300 to 900 ° C. in a nitrogen atmosphere, the temperature was increased to 1,300 ° C. and fired to obtain a carbon fiber bundle. It was. After performing an electrolytic surface treatment of 3 coulombs per gram of carbon fiber with an aqueous solution containing sulfuric acid as an electrolyte for this carbon fiber bundle, further applying a sizing agent by an immersion method, drying in heated air at a temperature of 120 ° C., Reinforcing fiber bundle A2 (PAN-based carbon fiber) was obtained. The physical properties of the reinforcing fiber bundle A2 are shown below.

Total number of filaments: 12,000 Single fiber diameter: 7 μm
Mass per unit length: 0.8 g / m
Specific gravity: 1.8 g / cm ³
Tensile strength: 4.2 GPa
Tensile modulus: 230 GPa
O / C: 0.10
Sizing agent type: polyoxyethylene oleyl ether Sizing agent adhesion amount: 0.6% by mass.

(Raw material 3) Reinforced fiber bundle A3 (PAN-based carbon fiber)
The reinforcing fiber bundle A3 was manufactured as follows.

Using a copolymer composed of 99.4 mol% of acrylonitrile (AN) and 0.6 mol% of methacrylic acid, an acrylic fiber bundle having a single fiber denier 1d and a filament number of 24,000 was obtained by a dry and wet spinning method. The obtained acrylic fiber bundle was heated at a draw ratio of 1.05 in air at a temperature of 240 to 280 ° C. to convert to a flameproof fiber. Next, the rate of temperature increase was set to 200 ° C./min, and after 10% stretching in a temperature range of 300 to 900 ° C. in a nitrogen atmosphere, the temperature was increased to 1,300 ° C. and fired to obtain a carbon fiber bundle. It was. This carbon fiber bundle was subjected to an electrolytic surface treatment of 80 coulomb per gram of carbon fiber with an aqueous solution containing ammonium bicarbonate as an electrolyte, and then a sizing agent was applied by a dipping method and dried in heated air at a temperature of 120 ° C. Thus, a reinforcing fiber bundle A3 (PAN-based carbon fiber) was obtained. The physical properties of the reinforcing fiber bundle A3 are shown below.
Total number of filaments: 24,000

Single fiber diameter: 7μm
Mass per unit length: 0.8 g / m
Specific gravity: 1.8 g / cm ³
Tensile strength: 4.2 GPa
Tensile modulus: 230 GPa
O / C: 0.20
Sizing agent type: Polyoxyethylene oleyl ether Sizing agent adhesion amount: 1.5 mass%.

(Raw material 4) Reinforced fiber bundle A4 (glass fiber)
The product name PF-E001 manufactured by Nittobo was used for the reinforcing fiber bundle A4.

(Raw material 5) Reinforcing fiber bundle A5 (PAN-based carbon fiber)
The reinforcing fiber bundle A5 was produced as follows.

  Using a copolymer composed of 99.4 mol% of acrylonitrile (AN) and 0.6 mol% of methacrylic acid, an acrylic fiber bundle having a single fiber denier 1d and a filament number of 24,000 was obtained by a dry and wet spinning method. The obtained acrylic fiber bundle was heated at a draw ratio of 1.05 in air at a temperature of 240 to 280 ° C. to convert to a flameproof fiber. Next, the rate of temperature increase was set to 200 ° C./min, and after 10% stretching in a temperature range of 300 to 900 ° C. in a nitrogen atmosphere, the temperature was increased to 1,300 ° C. and fired to obtain a carbon fiber bundle. It was. After performing an electrolytic surface treatment of 3 coulombs per gram of carbon fiber with an aqueous solution containing sulfuric acid as an electrolyte for this carbon fiber bundle, further applying a sizing agent by an immersion method, drying in heated air at a temperature of 120 ° C., Reinforcing fiber bundle A5 (PAN-based carbon fiber) was obtained. The physical properties of the reinforcing fiber bundle A5 are shown below.

Total number of filaments: 24,000 Single fiber diameter: 7 μm
Mass per unit length: 0.8 g / m
Specific gravity: 1.8 g / cm ³
Tensile strength: 4.2 GPa
Tensile modulus: 230 GPa
O / C: 0.10
Sizing agent: (Meth) acrylic polymer B1
Sizing adhesion amount: 0.5 mass%.

(Raw material 6) (Meth) acrylic polymer B1
Into a 1 L four-necked flask equipped with a stirrer, temperature sensor, reflux condenser and monomer dropping port, 137.4 g of ion-exchanged water was charged, and degassing and bubbling of nitrogen gas were repeated several times to obtain a dissolved oxygen concentration of 2 mg / L. After deoxygenating until it became below, temperature rising was started. In the subsequent emulsion polymerization process, nitrogen gas blowing was continued.

  100 g of a (meth) acrylic monomer mixture consisting of 35.0 g of methyl methacrylate, 54.0 g of n-butyl methacrylate, 1.0 g of acrylic acid and 10.0 g of 2-hydroxyethyl methacrylate, “Adekaliasorb® SR” -1025 "(Adeka Co., Ltd., reactive emulsifier, 25% aqueous solution) and 39.7 g of ion-exchanged water for pre-emulsion production were mixed and emulsified for 10 minutes at 10,000 rotations in an emulsifier. An emulsion was prepared.

  When the temperature in the flask reached 75 ° C. of the polymerization temperature, 10 wt% (14.8 g) of the pre-emulsion was added. When the temperature in the flask recovered to 75 ° C., the polymerization temperature, 0.2 g of ammonium persulfate as a polymerization initiator was added, and then emulsion polymerization was performed at 75 ° C. for 1 hour.

  The remaining 90 wt% (132.9 g) of the pre-emulsion was dropped into the flask over 3 hours, and after completion of the dropwise addition, polymerization was performed at 75 ° C. for another 30 minutes, and then the temperature was raised to 80 ° C. in 30 minutes to effect the aging reaction. went. After 30 minutes of temperature increase, 0.020 g of ammonium persulfate and 0.400 g of ion-exchanged water were added. After 30 minutes, 0.010 g of ammonium persulfate and 0.200 g of ion-exchanged water were further added. After carrying out the aging reaction, it was cooled.

  After cooling to 40 ° C. or lower, 0.05 g of “Adecanate (registered trademark) B-1016” (Adeka Co., Ltd. antifoaming agent) was added, and the mixture was further stirred and mixed for 30 minutes. 47 g and 393.5 g of ion exchange water for dilution were added to prepare an emulsion containing 15.0% by mass of (meth) acrylic polymer B1.

  Hereinafter, the (meth) acrylic monomer may be abbreviated as follows, including the description in the table. Methyl methacrylate (MMA), n-butyl methacrylate (BMA), cyclohexyl acrylate (CHA), isobornyl methacrylate (IBOMA), acrylic acid (AA), methacrylic acid (MAA), 2-hydroxyethyl methacrylate (HEMA) ), N- (2-methacryloyloxyethyl) ethylene urea (MEEU), N-2-hydroxyethyl acrylamide (HEAA).

(Raw material 7) (Meth) acrylic polymer B2
(Meth) except that 100 g of (meth) acrylic monomer mixture consisting of 60.0 g of n-butyl methacrylate, 36.0 g of isobornyl methacrylate, 1.0 g of acrylic acid and 3.0 g of 2-ethylhexyl methacrylate was used. An emulsion containing 15.0% by mass of (meth) acrylic polymer B2 was produced in the same manner as acrylic polymer B1.

(Raw material 8) (Meth) acrylic polymer B3
(Meth) acrylic except that 100 g of (meth) acrylic monomer mixture consisting of 29.0 g of methyl methacrylate, 60.0 g of cyclohexyl acrylate, 1.0 g of acrylic acid and 10.0 g of 2-hydroxyethyl methacrylate was used. In the same manner as the polymer B1, an emulsion containing 15.0% by mass of the (meth) acrylic polymer B3 was produced.

(Raw material 9) (Meth) acrylic polymer B4
100 g of a (meth) acrylic monomer mixture consisting of 30.0 g of methyl methacrylate, 50.0 g of cyclohexyl acrylate, 10.0 g of 2-hydroxyethyl methacrylate and 10.0 g of N- (2-methacryloyloxyethyl) ethylene urea An emulsion containing 15.0% by mass of (meth) acrylic polymer B4 was produced in the same manner as (meth) acrylic polymer B1 except that it was used.

(Raw material 10) (Meth) acrylic polymer B5
(Meth) acrylic polymer B1 except that 100 g of (meth) acrylic monomer mixture consisting of 30.0 g of methyl methacrylate, 50.0 g of cyclohexyl acrylate and 20.0 g of N-2-hydroxyethylacrylamide was used. Similarly, an emulsion containing 15.0% by mass of (meth) acrylic polymer B5 was produced.

(Raw material 11) (Meth) acrylic polymer B6
(Meth) except that 35.0 g of methyl methacrylate, 54.0 g of n-butyl methacrylate, 1.0 g of acrylic acid and 10.0 g of (meth) acrylic monomer mixture consisting of 10.0 g of 2-ethylhexyl methacrylate were used. An emulsion containing 15.0% by mass of (meth) acrylic polymer B6 was produced in the same manner as acrylic polymer B1.

(Raw material 12) Polyvinyl alcohol B7
Polyvinyl alcohol (degree of polymerization 2000) manufactured by Nacalai Tesque was used.

(Raw material 13) Thermoplastic resin C1 (acid-modified polypropylene resin)
“Admer (registered trademark)” QE510 manufactured by Mitsui Chemicals, Inc. was used. The physical properties are as follows.
Specific gravity: 0.91
Melting point: 160 ° C.

(Raw material 14) Thermoplastic resin C2 (polyamide 6 resin)
“Amilan (registered trademark)” CM1001 manufactured by Toray Industries, Inc. was used. The physical properties are as follows.
Specific gravity: 1.13
Melting point: 225 ° C.

(Raw material 15) Thermoplastic resin C3 (PPS resin)
“Torelina (registered trademark)” A900 manufactured by Toray Industries, Inc. was used. The physical properties are as follows.
Specific gravity: 1.34
Melting point: 278 ° C.

<Measurement of tensile strength and tensile modulus of reinforcing fiber bundle>
The tensile strength and tensile modulus of the reinforcing fiber bundle were determined by the method described in Japanese Industrial Standard (JIS) -R-7601 “Resin-impregnated strand test method”. However, the carbon fiber resin-impregnated strand to be measured is impregnated with “BAKELITE (registered trademark)” ERL 4221 (100 parts by mass) / 3 boron fluoride monoethylamine (3 parts by mass) / acetone (4 parts by mass). And cured at 130 ° C. for 30 minutes. The number of strands measured was 6, and the average value of each measurement result was the tensile strength and tensile modulus of the carbon fiber.

<Measurement of O / C measurement of reinforcing fiber bundle>
The surface oxygen concentration (O / C) of the reinforcing fiber bundle was determined by X-ray photoelectron spectroscopy according to the following procedure. First, carbon fibers from which the carbon fiber surface deposits and the like were removed with a solvent were cut into 20 mm, and spread on a copper sample support. A1Kα1 and 2 were used as the X-ray source, and the inside of the sample chamber was kept at 1 × 10 ⁸ Torr. The kinetic energy value (KE) of the main peak of C _1S was adjusted to 1202 cV as a peak correction value associated with charging during measurement. K. E. As a result, a C _1S peak area was obtained by drawing a straight base line within a range of 1191 to 1205 eV. K. E. As a result, an O _1S peak area was obtained by drawing a straight base line in the range of 947 to 959 eV.

The surface oxygen concentration O / C was calculated as an atomic number ratio from the ratio of the O _1S peak area to the C _1S peak area using a sensitivity correction value unique to the apparatus. As an X-ray photoelectron spectroscopy apparatus, Kokusai Denki Co., Ltd. model ES-200 was used, and the sensitivity correction value was set to 1.74.

<Measurement of amount of sizing agent attached to reinforcing fiber bundle>
As a sample, about 5 g of carbon fiber with a sizing agent attached thereto was collected and put into a heat-resistant container. The container was then dried at 120 ° C. for 3 hours. After being cooled to room temperature while taking care in a desiccator so as not to absorb moisture, the weighed mass was defined as W ₁ (g). Subsequently, the whole container was heated in a nitrogen atmosphere at 450 ° C. for 15 minutes, and then cooled to room temperature while taking care not to absorb moisture in a desiccator, and the weighed mass was defined as W ₂ (g). Through the above treatment, the amount of the sizing agent attached to the carbon fiber was determined by the following equation.
Adhering amount (% by mass) = 100 × {(W ₁ −W ₂ ) / W ₂ }
In addition, the measurement was performed 3 times and the average value was employ | adopted as adhesion amount.

  The evaluation criteria obtained in each example are as follows.

(Evaluation of production efficiency of fiber reinforced molding materials)
The time required to produce 10 kg of fiber reinforced molding material was measured and judged according to the following criteria.
A: Less than 30 minutes B: 30 minutes or more and less than 60 minutes C: 60 minutes or more and less than 120 minutes D: 120 minutes or more.

(Evaluation of dispersed state of reinforcing fiber in fiber reinforced molding material)
The base material was cut into a square shape of 50 mm × 50 mm from an arbitrary part of the obtained reinforcing fiber base material (A2), and observed with a microscope. A state where 10 or more carbon fibers were bundled, that is, the number of carbon fiber bundles with insufficient dispersion was measured. The measurement was performed 20 times in this procedure, and the number of carbon fiber bundles with insufficient dispersion was evaluated based on the average value. Judgment was made according to the following criteria.
A: Number of bundles of carbon fibers insufficiently dispersed is less than 1 B: Number of bundles of carbon fibers insufficiently dispersed is 1 or more and less than 5 C: Number of bundles of carbon fibers insufficiently dispersed is 5 Less than 10 D: The number of carbon fiber bundles with insufficient dispersion is 10 or more.

(Evaluation of specific strength of fiber reinforced molding material)
The obtained fiber-reinforced molding material was cut into 200 mm × 200 mm and dried at 120 ° C. for 1 hour. Four fiber-reinforced molding materials after drying are laminated, and the temperature is 230 ° C. when the thermoplastic resin (C) is an acid-modified polypropylene resin, the temperature is 250 ° C. when the polyamide 6 resin is used, and the temperature is 300 ° C. when the resin is a PPS resin. Then, press molding was performed at a pressure of 30 MPa for 5 minutes, and the molded product having a thickness of 1.0 mm was obtained by cooling to 50 ° C. while maintaining the pressure. A test piece was cut out from the molded article, and the specific gravity ρ of the molded article was measured based on ISO 1183 (1987). Then, a test piece was cut out from the molded article, and the tensile strength was measured according to ISO527-3 method (1995). The test piece was cut out in four directions of 0 °, + 45 °, −45 °, and 90 ° when an arbitrary direction was taken as the 0 ° direction to produce a test piece. The number of measurements in each direction was n = 5, and the average value of all measured values (n = 20) was taken as the tensile strength σc. As the measuring apparatus, “Instron (registered trademark)” 5565 type universal material testing machine (manufactured by Instron Japan Co., Ltd.) was used. From the obtained result, the specific strength of the molded product was calculated by the following formula.
Specific strength of molded product = σc / ρ
The determination was made according to the following criteria based on the specific strength of the molded product.
AAA: Specific strength 350 MPa or more
A: Specific strength 325 MPa or more and less than 350 MPa A: Specific strength 300 MPa or more and less than 325 MPa B: Specific strength 275 MPa or more and less than 300 MPa C: Specific strength 250 MPa or more and less than 275 MPa D: Specific strength less than 250 MPa.

(Evaluation of specific rigidity of fiber reinforced molding materials)
The obtained fiber-reinforced molding material was cut into 200 mm × 200 mm and dried at 120 ° C. for 1 hour. Four fiber-reinforced molding materials after drying are laminated, and the temperature is 230 ° C. when the thermoplastic resin (C) is an acid-modified polypropylene resin, the temperature is 250 ° C. when the polyamide 6 resin is used, and the temperature is 300 ° C. when the resin is a PPS resin. Then, press molding was performed at a pressure of 30 MPa for 5 minutes, and the molded product having a thickness of 1.0 mm was obtained by cooling to 50 ° C. while maintaining the pressure. A test piece was cut out from the molded article, and the flexural modulus was measured according to ISO 178 method (1993). The test piece was cut out in four directions of 0 °, + 45 °, −45 °, and 90 ° when an arbitrary direction was taken as the 0 ° direction to produce a test piece. The number of measurements in each direction was n = 5, and the average value of all measured values (n = 20) was defined as the flexural modulus Ec. As the measuring apparatus, “Instron (registered trademark)” 5565 type universal material testing machine (manufactured by Instron Japan Co., Ltd.) was used. From the obtained results, the specific rigidity of the molded product was calculated according to the following equation.
Specific rigidity of molded product = Ec ^1/3 / ρ (ρ: specific gravity of molded product)
The determination was based on the following criteria based on the specific rigidity of the molded product.
A: Specific rigidity 2.20 or more B: Specific rigidity 2.00 or more and less than 2.20 C: Specific rigidity 1.50 or more and less than 2.00 D: Specific rigidity less than 1.50.

(Evaluation of uniformity of molded products)
The coefficient of variation (CV value) of the evaluation result of the tensile strength of the molded product was evaluated. The determination was made according to the following criteria based on the coefficient of variation (CV value).
A: Variation coefficient less than 5 B: Variation coefficient 5 or more and less than 10 C: Variation coefficient 10 or more and less than 15 D: Variation coefficient 15 or more.

(Evaluation of tensile strength of reinforcing fiber substrate (A2))
From the reinforcing fiber base (A2), when an arbitrary direction is set to 0 °, test pieces having a width of 12.5 mm and a length of 200 mm in four directions of 0 °, + 45 °, −45 °, and 90 ° are obtained. Produced. A tensile test was conducted at a tensile rate of 1.6 mm / min, and the tensile strength (N / cm) was measured by dividing the load at the time of breaking the reinforcing fiber base (A2) by the width of 12.5 mm. The number of measurements in each direction was n = 5, and the average value of all measured values (n = 20) was taken as the tensile strength.

Example 1 Production of Fiber Reinforced Molding Material Using Wet Process A reinforced fiber substrate (A2) was produced using the apparatus 3 shown in FIG. The apparatus 3 includes a dispersion tank 4, a papermaking tank 6, and a supply tank 9. The dispersion tank 4 is a cylindrical container having a diameter of 500 mm, and includes an opening cock 5 at the bottom of the container. The papermaking tank 6 includes a mesh conveyor 8 having a papermaking surface 7 having a width of 300 mm at the bottom. The supply tank 9 supplies the emulsion of the (meth) acrylic polymer (B) to the reinforcing fiber base (A1) 11. The supply tank 9 is provided with an opening cock 5. The emulsion applying part 10 of the (meth) acrylic polymer (B) is a curtain coat type, and the emulsion of the (meth) acrylic polymer can be uniformly distributed on the reinforcing fiber base (A1) 11. A stirrer 12 is attached to the opening on the upper surface of the dispersion tank 4, and the reinforcing fiber bundle 13 and the dispersion medium 2 can be introduced from the opening.

  First, the reinforcing fiber bundle A1 (carbon fiber) was cut into 6 mm with a cartridge cutter to obtain chopped carbon fiber.

  A dispersion liquid having a concentration of 0.1% by mass composed of water and a surfactant (manufactured by Nacalai Tex Co., Ltd., polyoxyethylene lauryl ether (trade name)) is placed in the dispersion tank 4, and the chopped carbon fiber is used as a fiber. Was added so that the mass content of was 0.02 mass%. After preparing the slurry by stirring for 5 minutes, the opening cock 5 at the bottom of the container is opened, the slurry is poured onto a mesh conveyor 8 having a papermaking surface 7 having a width of 300 mm, and the water is sucked and taken up. A reinforcing fiber substrate (A1) 11 having a width of 300 mm was obtained. Subsequently, the opening cock 5 of the supply tank 9 was opened, and a 1% by mass emulsion solution of the (meth) acrylic polymer B1 was sprayed on the upper surface of the reinforcing fiber base (A1). After the excess emulsion liquid was sucked, the reinforcing fiber base material was passed through a drying furnace 14 at 200 ° C. for 3 minutes and wound up by a winder 18 to give the (meth) acrylic polymer B1. A reinforcing fiber substrate (A2) 15 was obtained.

The obtained reinforcing fiber substrate (A2) 15 was taken out from the production apparatus 3 and set in the apparatus 20 of FIG. 3 provided with a double belt press apparatus 19 capable of pressurization, heating and cooling. The apparatus 20 includes creels 16 for containing C1 non-woven fabric (resin basis weight 100 g / m ² ) as a thermoplastic resin at two places above and below the introduction part of the double belt press apparatus 19, and includes a reinforcing fiber base (A 2) 15. Is provided with a winder 18 for taking up the fiber-reinforced molding material 17 impregnated with the thermoplastic resin C1.

The nonwoven fabric (weight per unit area: 100 g / m ² ) of the thermoplastic resin C1 supplied from the creel 16 to the reinforcing fiber substrate (A2) was sandwiched from above and below and introduced into the double belt press device 19. In the double belt press 19, the first half is heated and pressurized at 230 ° C. and 3.5 MPa, the second half is cooled and pressurized at 60 ° C. and 3.5 MPa, and the reinforcing fiber substrate (A 2) and the thermoplastic resin C 1. As a result, a fiber reinforced molding material 17 was obtained.

  The compounding amounts of the reinforcing fiber bundle, the (meth) acrylic polymer (B), and the thermoplastic resin (C) are as shown in Table 2. In addition, Table 2 shows implementation conditions in each step and evaluation results of the obtained reinforcing fiber base material and fiber-reinforced molding material.

Example 2 Production of Fiber Reinforced Molding Material Using Wet Process A fiber reinforced molded substrate was produced using the apparatus 21 shown in FIG. The device 21 is a device in which the device 20 is integrated with the device 3. A fiber reinforced molding material was obtained in the same manner as in Example 1 except that the reinforcing fiber bundle and the dispersion medium were continuously added using the apparatus 21 and the entire process was performed online. Table 2 shows the blending amounts of the materials, the implementation conditions in each step, and the evaluation results of the obtained reinforcing fiber base material and fiber reinforced molding material.

(Example 3) Production of fiber reinforced molding material using wet process
A fiber reinforced molding material was obtained in the same manner as in Example 2 except that the amount of the (meth) acrylic polymer (B) was 0.4% by mass. Table 2 shows the blending amounts of the materials, the implementation conditions in each step, and the evaluation results of the obtained reinforcing fiber base material and fiber reinforced molding material.

Example 4 Production of Fiber Reinforced Molding Material by Dry Process A fiber reinforced molded substrate was produced using the apparatus 22 of FIG. The device 22 is a device in which the structure of the papermaking portion of the device 21 is replaced with a card machine 23. A fiber reinforced molding material is obtained in the same manner as in Example 2 except that the reinforcing fiber bundle A2 is continuously charged as a reinforcing fiber bundle into the card machine 23 using the apparatus 22 and the entire process is performed online. It was. Table 2 shows the blending amounts of the materials, the implementation conditions in each step, and the evaluation results of the obtained reinforcing fiber base material and fiber reinforced molding material.

(Example 5) Manufacture of fiber reinforced molding material using wet process The concentration of the reinforcing fiber in the slurry in the dispersion tank 4 is 0.04 mass%, and the dispersion medium 2 is continuously supplied in the papermaking tank 6 The treatment was performed in the same manner as in Example 2 except that the concentration of the reinforcing fiber was reduced to 0.02% by mass to obtain a fiber-reinforced molding material. Table 2 shows the blending amounts of the materials, the implementation conditions in each step, and the evaluation results of the obtained reinforcing fiber base material and fiber reinforced molding material.

(Example 6) Manufacture of fiber reinforced molding material using wet process Except that the concentration of the reinforcing fiber in the slurry in the dispersion tank 4 was 1.5% by mass, the same treatment as in Example 2 was performed, and the fiber reinforced A molding material was obtained. Table 2 shows the blending amounts of the materials, the implementation conditions in each step, and the evaluation results of the obtained reinforcing fiber base material and fiber reinforced molding material.

(Example 7) Manufacture of fiber reinforced molding material using wet process Except that the concentration of the reinforcing fiber in the slurry in the dispersion tank 4 was 0.1% by mass, the same treatment as in Example 2 was performed, and the fiber reinforced A molding material was obtained. Table 3 shows the blending amounts of the materials, the implementation conditions in each step, and the evaluation results of the obtained reinforcing fiber base material and fiber-reinforced molding material.

(Example 8) Manufacture of fiber reinforced molding material using wet process The reinforcing fiber and the cut fiber of the thermoplastic resin are put into the slurry in the dispersion tank 4, and the concentration of the reinforcing fiber is 0.02% by mass, thermoplasticity. A non-woven fabric of the thermoplastic resin C1 supplied from the creel 16 with a concentration of resin cut fibers (single fiber fineness 3 dtex, cut length 6 mm) of 0.03% by mass and a total concentration of solid components of 0.05% by mass. A fiber reinforced molding material was obtained in the same manner as in Example 2 except that it was introduced into the double belt press device 19 without being used. Table 3 shows the blending amounts of the materials, the implementation conditions in each step, and the evaluation results of the obtained reinforcing fiber base material and fiber-reinforced molding material.

(Example 9) Manufacture of fiber reinforced molding material using wet process The same procedure as in Example 2 was performed except that (meth) acrylic polymer B2 was used as (meth) acrylic polymer (B). A fiber reinforced molding material was obtained. Table 3 shows the blending amounts of the materials, the implementation conditions in each step, and the evaluation results of the obtained reinforcing fiber base material and fiber-reinforced molding material.

(Example 10) Manufacture of fiber-reinforced molding material using a wet process The same treatment as in Example 2 was performed except that (meth) acrylic polymer B3 was used as (meth) acrylic polymer (B). A fiber reinforced molding material was obtained. Table 3 shows the blending amounts of the materials, the implementation conditions in each step, and the evaluation results of the obtained reinforcing fiber base material and fiber-reinforced molding material.

(Example 11) Manufacture of fiber reinforced molding material using wet process Except having used reinforcing fiber bundle A3 as a reinforcing fiber bundle, it processed similarly to Example 2 and obtained the fiber reinforced molding material. Table 3 shows the blending amounts of the materials, the implementation conditions in each step, and the evaluation results of the obtained reinforcing fiber base material and fiber-reinforced molding material.

( Comparative Example 1 ) Manufacture of fiber reinforced molding material using wet process Except for using reinforced fiber bundle A4 as the reinforcing fiber bundle, the same treatment as in Example 2 was performed to obtain a fiber reinforced molding material. Table 3 shows the blending amounts of the materials, the implementation conditions in each step, and the evaluation results of the obtained reinforcing fiber base material and fiber-reinforced molding material.

(Example 13) Manufacture of fiber reinforced molding material using wet process The same procedure as in Example 2 was performed except that (meth) acrylic polymer B4 was used as (meth) acrylic polymer (B). A fiber reinforced molding material was obtained. Table 4 shows the blending amounts of the materials, the implementation conditions in each step, and the evaluation results of the obtained reinforcing fiber base material and fiber-reinforced molding material.

(Example 14) Manufacture of fiber-reinforced molding material using wet process The same procedure as in Example 2 was performed except that (meth) acrylic polymer B5 was used as (meth) acrylic polymer (B). A fiber reinforced molding material was obtained. Table 4 shows the blending amounts of the materials, the implementation conditions in each step, and the evaluation results of the obtained reinforcing fiber base material and fiber-reinforced molding material.

(Example 15) Manufacture of fiber reinforced molding material using wet process Using thermoplastic resin C2 as the thermoplastic resin (C), in the double belt press device 19, except that the temperature was 250 ° C in the first half, The same treatment as in Example 2 was performed to obtain a fiber reinforced molding material. Table 4 shows the blending amounts of the materials, the implementation conditions in each step, and the evaluation results of the obtained reinforcing fiber base material and fiber-reinforced molding material.

(Example 16) Manufacture of fiber reinforced molding material using wet process Using thermoplastic resin C3 as the thermoplastic resin (C), in the double belt press device 19, except that the temperature was 300 ° C in the first half, The same treatment as in Example 2 was performed to obtain a fiber reinforced molding material. Table 4 shows the blending amounts of the materials, the implementation conditions in each step, and the evaluation results of the obtained reinforcing fiber base material and fiber-reinforced molding material.

(Example 17) Manufacture of fiber reinforced molding material using dry process In the apparatus 22 of FIG. 5, without using the supply tank 9 of the (meth) acrylic polymer (B), the (meth) acrylic polymer was previously prepared. A fiber-reinforced molding material was obtained in the same manner as in Example 4 except that the reinforcing fiber bundle A5 provided with (B) was continuously added to the card machine 23 portion. Table 5 shows the blending amounts of the materials, the implementation conditions in each step, and the evaluation results of the obtained reinforcing fiber base material and fiber-reinforced molding material.

(Example 18) Manufacture of fiber reinforced molding material using wet process In the apparatus 21 of FIG. 4, without using the supply tank 9 of the (meth) acrylic polymer (B), the (meth) acrylic polymer was previously prepared. The treatment was performed in the same manner as in Example 2 except that the reinforcing fiber bundle A5 provided with (B) was used, and a fiber-reinforced molding material was obtained. Table 5 shows the blending amounts of the materials, the implementation conditions in each step, and the evaluation results of the obtained reinforcing fiber base material and fiber-reinforced molding material.

Example 19 Production of Fiber Reinforced Molding Material Using Dry Process A fiber reinforced molded substrate was produced using the apparatus 26 of FIG. In the apparatus 26, the emulsion tank (9) of the (meth) acrylic polymer (B) of the apparatus 22 is installed in the card machine 23, and the (meth) acrylic heavy weight is produced simultaneously with the production of the reinforcing fiber base (A1). It is an apparatus that can apply the combined body (B) to the reinforcing fiber substrate (A1). A fiber-reinforced molding material was obtained in the same manner as in Example 4 except that the reinforcing fiber bundle A1 was continuously charged as a reinforcing fiber bundle into the card machine 23 using the device 26. Table 6 shows the blending amounts of the materials, the implementation conditions in each step, and the evaluation results of the obtained reinforcing fiber base material and fiber-reinforced molding material.

Example 20 Production of Fiber Reinforced Molding Material Using Wet Process A fiber reinforced molded substrate was produced using the apparatus 27 of FIG. The device 27 is a device in which the emulsion tank 9 of the (meth) acrylic polymer (B) of the device 21 is installed in the dispersion tank 4 portion. It is possible to continuously supply the (meth) acrylic polymer (B) to the dispersion tank 4, and at the same time as the production of the reinforcing fiber base (A1), the (meth) acrylic polymer (B) is used as the reinforcing fiber. It can give to a base material (A1). Except having supplied the (meth) acrylic-type polymer (B) continuously to the dispersion tank 4 using the apparatus 26, it processed similarly to Example 2 and obtained the fiber reinforced molding material. Table 6 shows the blending amounts of the materials, the implementation conditions in each step, and the evaluation results of the obtained reinforcing fiber base material and fiber-reinforced molding material.

(Comparative example 1) Manufacture of the fiber reinforced molding material using a wet process The reinforced fiber base material (A2) was manufactured using the apparatus 25 of FIG. The apparatus 6 includes a dispersion tank 4, a papermaking tank 6, and a supply tank 9. The dispersion tank 4 is a cylindrical container having a diameter of 500 mm provided with an opening cock 5 at the lower part of the container. The papermaking tank 6 is a tank provided with a mesh sheet 24 having a square papermaking surface 7 of 300 mm square at the bottom. The supply tank 9 supplies the emulsion of the (meth) acrylic polymer (B) to the reinforcing fiber base (A1) 11. The supply tank 9 is provided with an opening cock 5. The emulsion application part 10 of the (meth) acrylic polymer (B) has a movable opening cock outlet, and the emulsion of the (meth) acrylic polymer can be uniformly distributed on the reinforcing fiber substrate (A1) 11. is there. A stirrer 12 is attached to the opening on the upper surface of the dispersion tank 4, and the reinforcing fiber bundle 13 and the dispersion medium 2 can be introduced from the opening. In addition, the apparatus 6 is a batch type manufacturing apparatus and cannot take up the reinforcing fiber base (A1). After the reinforcing fiber base (A1) 11 is formed on the papermaking surface 7 of the mesh sheet 24, the (meth) acrylic polymer (B) is applied. The reinforcing fiber substrate to which the (meth) acrylic polymer (B) is applied is taken out from the device 25, put into a dryer and dried to obtain the reinforcing fiber substrate (A2).

As the thermoplastic resin (C), a nonwoven fabric of thermoplastic resin C1 (resin weight 100 g / m ² ) is placed one by one above and below the reinforcing fiber substrate (A2) and heated at a temperature of 230 ° C. and 3.5 MPa for 5 minutes. Pressurized, and then cooled and pressurized at 60 ° C. and 3.5 MPa for 5 minutes to obtain a fiber-reinforced molding material in which the reinforcing fiber substrate (A2) and the thermoplastic resin C1 were combined. Table 6 shows the blending amounts of the materials, the implementation conditions in each step, and the evaluation results of the obtained reinforcing fiber base material and fiber-reinforced molding material.

(Comparative example 2) Manufacture of the fiber reinforced molding material using a wet process Except not having provided the (meth) acrylic-type polymer (B), it processed similarly to Example 2, and produced the fiber reinforced molding material. Obtained. Table 6 shows the blending amounts of the materials, the implementation conditions in each step, and the evaluation results of the obtained reinforcing fiber base material and fiber-reinforced molding material.

(Comparative example 3) Manufacture of the fiber reinforced molding material using a wet process It processed like Example 2 except having used (meth) acrylic-type polymer B6 as (meth) acrylic-type polymer (B). The fiber reinforced molding material was obtained. Table 6 shows the blending amounts of the materials, the implementation conditions in each step, and the evaluation results of the obtained reinforcing fiber base material and fiber-reinforced molding material.

(Comparative example 4) Manufacture of fiber reinforced molding material using wet process Except having used polyvinyl alcohol B7 instead of (meth) acrylic polymer (B), it processed like Example 2, and fiber A reinforced molding material was obtained. Table 6 shows the blending amounts of the materials, the implementation conditions in each step, and the evaluation results of the obtained reinforcing fiber base material and fiber-reinforced molding material.

As is clear from Tables 2 to 7, in Examples 1 to 11 and 13 to 20, all are excellent in the dispersion state of carbon fibers in a short time, and fiber reinforcement capable of maintaining high mechanical properties even when formed into a molded product. A molding material could be obtained. In particular, the raw materials are continuously added, the entire process is performed online, and the application of the (meth) acrylic polymer (B) is performed later, so that a fiber-reinforced molding material having excellent mechanical properties when formed into a molded product. It could be produced efficiently (see Examples 2, 18, 20 and Comparative Example 1). Further, it was found that by setting C1 / C2 in the range of 0.8 to 1.2, a more excellent dispersion state of the reinforcing fibers can be secured, and the mechanical properties of the obtained molded article are improved (Example 2). See Example 5).

  Further, when the (meth) acrylic polymer (B) was not used, it was impossible to take up the reinforcing fiber base (Comparative Example 2). Furthermore, when the (meth) acrylic polymer (B) does not have a hydroxyl group on the side difference (Comparative Example 3), or when polyvinyl alcohol is used instead of the (meth) acrylic polymer (B) ( In Comparative Example 4), the mechanical properties of the obtained molded product were greatly inferior.

DESCRIPTION OF SYMBOLS 1 Reinforcing fiber 2 Dispersion medium 3 Reinforcing fiber substrate (A1), (A2) manufacturing apparatus 4 Dispersion tank 5 Opening cock 6 Papermaking tank 7 Papermaking surface 8 Mesh conveyor 9 Supply tank for (meth) acrylic polymer (B) 10 (meth) acrylic polymer emulsion applying part 11 Reinforcing fiber substrate (A1)
12 Stirrer 13 Reinforcing fiber bundle 14 Dryer 15 Reinforcing fiber substrate (A2)
16 Creel 17 Fiber Reinforced Molding Material 18 Winding Machine 19 Double Belt Press Device 20 Fiber Reinforced Molding Material Manufacturing Device 21 Reinforced Fiber Base Material (A1), (A2), Fiber Reinforced Molded Material Manufacturing Device 22 Reinforced Fiber Base Material ( A1), (A2), fiber reinforced molding material manufacturing device 23 card machine 24 mesh sheet 25 reinforced fiber base material (A1), (A2), fiber reinforced molding material manufacturing device 26 manufacturing of reinforced fiber base material (A1) apparatus

Claims (15)

A method for producing a carbon fiber reinforced molding material comprising the following steps 1a, 2a, 3a and 4a;
1a: a step of processing a discontinuous carbon fiber bundle into a sheet-like carbon fiber substrate (A1);
2a: 0.1 to 10 parts by mass of (meth) acrylic polymer (B) having a hydroxyl group in the side chain is added to 1 to 70 parts by mass of the carbon fiber base material (A1) obtained in step 1a. The step of:
3a: The carbon fiber substrate (A2) to which the (meth) acrylic polymer (B) obtained in the step 2a was added is combined with the thermoplastic resin (C) to obtain a carbon fiber substrate ( A2) a step of obtaining a carbon fiber reinforced molding material containing 1.1 to 80% by mass and thermoplastic resin (C) 20 to 98.9% by mass;
4a: A step of drawing the carbon fiber reinforced molding material obtained in the step 3a at a speed of 1 m / min or more. A method for producing a carbon fiber reinforced molding material comprising the following step 1b, step 2b and step 3b;
The 1b: to the carbon fiber bundle 1 to 70 parts by weight, having a hydroxyl group in the side chain (meth) acrylic polymer (B) is adhered 0.1-10 parts by weight, the discontinuous carbon fiber bundle sheet A step of processing into a carbon fiber substrate (A2) having a shape;
2b: The thermoplastic resin (C) 20 to 98.% is added to 1.1 to 80% by mass of the carbon fiber substrate (A2) to which the (meth) acrylic polymer (B) obtained in the step 1b is applied. A step of compounding 9% by mass to obtain a carbon fiber reinforced molding material;
3b: A step of drawing the carbon fiber reinforced molding material obtained in the 2b step at a speed of 1 m / min or more. A method for producing a carbon fiber reinforced molding material, comprising the following first c step, second c step and third c step;
1c: A discontinuous carbon fiber bundle is processed into a sheet-like carbon fiber substrate (A1), and at the same time a (meth) acrylic polymer (B) having a hydroxyl group in a side chain is converted into the carbon fiber substrate (A1). the carbon fiber substrate (A1) 0.1 to 10 parts by weight given to 1 to 70 parts by weight, to obtain a (meth) acrylic-based carbon fiber substrate polymer has been applied (A2) step;
2c: The carbon fiber substrate (A2) provided with the (meth) acrylic polymer (B) obtained in the step 1c, 1.1 to 80% by mass, the thermoplastic resin (C) 20 to 98. .Combining 9% by mass to obtain a carbon fiber reinforced molding material;
3c: A step of drawing the carbon fiber reinforced molding material obtained in the 2c step at a speed of 1 m / min or more. The manufacturing method of the carbon fiber reinforced molding material in any one of Claims 1-3 whose said carbon fiber base material (A1) is the short fiber random orientation base material obtained by processing by the following method a;
Method a: introducing a discontinuous carbon fiber bundle into the dispersion medium (i);
A step (ii) of preparing a slurry in which carbon fibers constituting the carbon fiber bundle are dispersed in the dispersion medium;
Removing the dispersion medium from the slurry to obtain a carbon fiber substrate (A1) (iii); and
When the mass content of the carbon fiber in the slurry prepared in the step (ii) is C1, and the mass content of the carbon fiber in the slurry at the start of the step (iii) is C2, C1 / C2 is 0.8 to 1.2. The carbon fiber substrate (A2) provided with the (meth) acrylic polymer (B) obtained in any one of the steps 2a, 1b and 1c has a tensile strength of 1 N / cm or more. The manufacturing method of the carbon fiber reinforced molding material in any one of Claims 1-4 picked up as this state. The manufacturing method of the carbon fiber reinforced molding material of Claim 4 or 5 whose solid component density | concentration in the slurry prepared by the said process (ii) is 0.001-1 mass%. The dispersion medium and the carbon fiber bundle are continuously charged into the dispersion tank in the step (i), and the steps (i) to (iii) are continuously performed. The manufacturing method of the carbon fiber reinforced molding material of description. The manufacturing method of the carbon fiber reinforced molding material in any one of Claims 1-7 by which all processes are implemented online. Manufacturing of the carbon fiber reinforced molding material in any one of Claims 1-8 whose ratio of carbon fiber is 80 to 100 mass% among the mass of solid content in the said carbon fiber base material (A2). Method. The 1a step, in any step of 1b step and 1c process, when processing a carbon fiber substrate (A1), carbon fiber substrate thermoplastic resin (C) in fibrous or particulate form The manufacturing method of the carbon fiber reinforced molding material in any one of Claims 1-8 mixed in (A1). The step of cutting the obtained carbon fiber reinforced molding material into 1 to 30 mm in both the length direction and the width direction after any of the steps 4a, 3b and 3c. The manufacturing method of the carbon fiber reinforced molding material in any one. The manufacturing method of the carbon fiber reinforced molding material in any one of Claims 1-11 whose cohesive energy density CED of the said (meth) acrylic-type polymer (B) is 385 Mpa or more. The (meth) acrylic monomer constituting the (meth) acrylic polymer (B) is a (meth) acrylic monomer in which an acryloyloxy group or a methacryloyloxy group is bonded to hydrogen and / or a primary carbon atom. The manufacturing method of the carbon fiber reinforced molding material in any one of Claims 1-12 whose mass body is 60 mass% or more . The manufacturing method of the carbon fiber reinforced molding material in any one of Claims 1-13 whose surface oxygen concentration O / C measured by the X ray photoelectron spectroscopy of the said carbon fiber is 0.05-0.5. The carbon according to any one of claims 1 to 14 , wherein the thermoplastic resin (C) is a thermoplastic resin containing at least one selected from polyolefin, polyamide, polycarbonate, polyester, polyphenylene sulfide, polyphenylene ether, and PEEK. A method for producing a fiber-reinforced molding material.

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