JP6225556B2 - Sheet for fiber-reinforced plastic molded body and fiber-reinforced plastic molded body - Google Patents

Description

  The present invention relates to a sheet for a fiber-reinforced plastic molded body and a fiber-reinforced plastic molded body. Specifically, the present invention relates to a fiber reinforced plastic molded sheet containing reinforcing fibers, a matrix resin fiber containing thermoplastic fibers, a binder component and a coupling agent, and a hot-press molding of the fiber reinforced plastic molded sheet. It is related with the fiber reinforced plastic molding formed by doing.

  Fiber reinforced plastic moldings obtained by heating and pressurizing nonwoven fabrics containing reinforcing fibers such as carbon fibers and glass fibers have already been used in various fields such as sports, leisure goods and aircraft materials. Thermosetting resins such as epoxy resins, unsaturated polyester resins, or phenol resins are often used as the resin that forms the matrix in these fiber-reinforced plastic molded articles.

  In the fiber reinforced plastic molded article using the thermosetting resin as described above, an attempt has been made to blend inorganic particles into the matrix resin in order to improve the strength. For example, Patent Document 1 discloses a matrix resin composition containing an inorganic particle resin treated with a coupling agent. Here, a thermosetting resin is mainly used for the matrix resin fiber. Patent Document 2 discloses a sheet for a fiber-reinforced plastic molded body containing a thermosetting resin, inorganic particles, and a coupling agent. Here, the coupling agent has a functional group capable of reacting with a thermosetting resin, and it has been proposed to improve compressive strength and bending strength by using such a coupling agent.

JP-A-8-157620 JP 2012-149237 A

However, when a thermosetting resin is used as the matrix resin fiber, the resulting fiber reinforced plastic molded sheet must be refrigerated and cannot be stored for a long time.
In order to solve such a problem, it is conceivable to form a sheet for a fiber-reinforced plastic molded body using a thermoplastic resin instead of the thermosetting resin. This is because a sheet for a fiber-reinforced plastic molded body using a thermoplastic resin as a matrix resin has the advantages of easy storage management and long-term storage.

  However, when a fiber-reinforced plastic molded body is formed from a sheet for a fiber-reinforced plastic molded body using a conventional thermoplastic resin, there is a problem that its strength and flame retardancy are not sufficient.

  In addition, a sheet for a fiber reinforced plastic molded body using a combination of a thermoplastic resin, a reinforcing fiber, and a coupling agent has not yet been sufficiently studied, and a combination of a thermoplastic resin, a reinforcing fiber, and a coupling agent has been used. The functions that can sometimes be exhibited were unknown.

  Therefore, in order to solve the problems of the prior art, the present inventors are a sheet for a fiber reinforced plastic molded body capable of molding a fiber reinforced plastic molded body having excellent strength and flame retardancy, The study was conducted with the aim of providing a sheet for a fiber-reinforced plastic molded article excellent in handling in the body processing step.

As a result of earnest studies to solve the above problems, the present inventors have reinforced fiber reinforcement containing reinforcing fibers, matrix resin fibers containing thermoplastic super engineering plastic fibers, a binder component, and a coupling agent. It has been found that a fiber reinforced plastic molded article having excellent strength and flame retardancy can be efficiently produced by setting the critical oxygen index of the thermoplastic super engineering plastic fiber to 24 or more in the plastic molded sheet. Furthermore, the present inventors have found that the production efficiency of a fiber-reinforced plastic molded body can be increased by using such a sheet for a fiber-reinforced plastic molded body, and have completed the present invention.
Specifically, the present invention has the following configuration.

[1] It contains a reinforcing fiber, a matrix resin fiber containing a thermoplastic super engineering plastic fiber, a binder component, and a coupling agent, and the limiting oxygen index of the thermoplastic super engineering plastic fiber is 24 or more. Fiber reinforced plastic molded sheet.
[2] The fiber-reinforced plastic molded sheet according to [1], wherein the reinforcing fiber is at least one selected from glass fiber, carbon fiber, and aramid fiber.
[3] The fiber diameter of the thermoplastic super engineering plastic fiber is 40 μm or less, and the fiber diameter of the thermoplastic super engineering plastic fiber is 5 times or less of the fiber diameter of the reinforcing fiber [1] or The sheet for fiber-reinforced plastic molded bodies according to [2].
[4] The fiber reinforced plastic molding according to any one of [1] to [3], wherein the thermoplastic super engineering plastic fiber is at least one selected from polyetherimide fiber or polycarbonate fiber. Body sheet.
[5] The fiber-reinforced plastic molded sheet according to any one of [1] to [4], wherein the thermoplastic super engineering plastic fiber is a polyetherimide (PEI) fiber.
[6] JAPAN TAPPI Paper Pulp Test Method No. The sheet for fiber-reinforced plastic molded bodies according to any one of [1] to [5], wherein the air permeability defined in 5-2 is 250 seconds or less.
[7] The sheet for fiber-reinforced plastic molded body according to any one of [1] to [6], wherein the thermoplastic super engineering plastic fiber and the reinforcing fiber are chopped strands.
[8] The fiber-reinforced plastic molded sheet according to any one of [1] to [7], wherein the coupling agent is a silane coupling agent.
[9] The silane coupling agent contains, as a functional group, a group selected from an amino group, vinyl group, epoxy group, styryl group, methacryloxy group, acryloxy group, ureido group, mercapto group, polysulfide group and isocyanate group. The sheet for fiber-reinforced plastic molded article according to [8], which is a product.
[10] Any one of [1] to [9], wherein the binder component is contained in an amount of 0.1 to 10% by mass relative to the total mass of the fiber-reinforced plastic molded sheet. The sheet | seat for fiber reinforced plastic moldings as described in 2.
[11] The fiber-reinforced plastic molded sheet according to any one of [1] to [10], wherein the binder component is compatible with the thermoplastic super engineering plastic fiber in a heated and melted state.
[12] The binder component contains a copolymer containing at least one of a repeating unit derived from a methyl (meth) acrylate-containing monomer and a repeating unit derived from an ethyl (meth) acrylate-containing monomer [1] ] The sheet | seat for fiber reinforced plastic moldings of any one of [11].
[13] The fiber according to any one of [1] to [12], wherein the binder component contains a binder fiber having a melting point lower than a glass transition temperature of the thermoplastic super engineering plastic fiber. Sheet for reinforced plastic moldings.
[14] The fiber-reinforced plastic molded sheet according to [13], wherein the binder fiber includes polyethylene terephthalate or modified polyethylene terephthalate.
[15] The fiber-reinforced plastic molded sheet has a surface layer region and an intermediate region sandwiched between the surface layer regions, and the binder component contained in the surface layer region is a binder component contained in the intermediate region. The sheet for fiber-reinforced plastic molded bodies according to any one of [1] to [14], characterized in that it is more.
[16] The copolymer contained in the binder component is localized in the form of a drainage film at the intersection of the fibers constituting the reinforcing fiber and the matrix resin fiber [12] to [15] ] The sheet | seat for fiber reinforced plastics molded objects of any one of.
[17] A fiber reinforced plastic including a step of mixing a reinforcing fiber, a matrix resin fiber containing a thermoplastic super engineering plastic fiber, a binder component, and a coupling agent, and forming a nonwoven fabric sheet by a dry nonwoven fabric method or a wet nonwoven fabric method. In the manufacturing method of the sheet | seat for molded objects, the critical oxygen index of the said thermoplastic super engineering plastic fiber is 24 or more, The manufacturing method of the sheet | seat for fiber reinforced plastics molded objects characterized by the above-mentioned.
[18] The step of forming the nonwoven fabric sheet includes a step of internally adding, coating or impregnating the nonwoven fabric sheet with a solution containing the binder component or an emulsion containing the binder component, and drying by heating. 17]. The manufacturing method of the sheet | seat for fiber reinforced plastic moldings as described in 17].
[19] The fiber-reinforced plastic molded sheet according to any one of [1] to [16] is formed by heat and pressure molding at a temperature equal to or higher than the glass transition temperature of the thermoplastic super engineering plastic fiber. A fiber-reinforced plastic molding.
[20] Fiber-reinforced plastic molding formed by heat-pressing the sheet for fiber-reinforced plastic molded body according to any one of [1] to [16] at a temperature of 150 to 600 ° C. body.

  By using the sheet for fiber-reinforced plastic molded article of the present invention, a fiber-reinforced plastic molded article having excellent strength and flame retardancy can be obtained. Furthermore, if the fiber-reinforced plastic molded sheet of the present invention is used, it becomes possible to efficiently and continuously produce a fiber-reinforced plastic molded body, and the manufacturing cost can be suppressed.

  Hereinafter, the present invention will be described in detail. The description of the constituent elements described below may be made based on representative embodiments and specific examples, but the present invention is not limited to such embodiments. In the present specification, a numerical range expressed using “to” means a range including numerical values described before and after “to” as a lower limit value and an upper limit value.

(Fiber-reinforced plastic molded sheet)
The present invention relates to a fiber-reinforced plastic molded sheet comprising a mixture of reinforcing fibers and matrix resin fibers containing thermoplastic super engineering plastic fibers, and further containing a binder component and a coupling agent. Here, the limiting oxygen index of the thermoplastic super engineering plastic fiber is 24 or more.
Thus, in the present invention, a thermoplastic super engineering plastic fiber having a critical oxygen index of 24 or more is used, and a fiber reinforced plastic molded sheet is formed by combining a reinforcing fiber, a binder component, and a coupling agent. A fiber-reinforced plastic molded article having high strength and flame retardancy can be molded. The strength and flame retardancy of the fiber reinforced plastic molded article obtained by molding the sheet for fiber reinforced plastic molded article of the present invention are superior to the case of using a conventional thermoplastic resin.

  In the fiber-reinforced plastic molded sheet of the present invention, the mass ratio of the reinforcing fiber and the thermoplastic super engineering plastic fiber is preferably 1: 0.2 to 1:10, and preferably 1: 0.5 to 1: 5. It is more preferable that the ratio is 1: 0.7 to 1: 3. By setting the mass ratio of the reinforcing fiber and the thermoplastic super engineering plastic fiber within the above range, a lightweight and high-strength fiber-reinforced plastic molded body can be obtained.

  In general, since the matrix resin has a high melt viscosity, it is difficult to uniformly disperse the reinforcing fibers when a large amount of the reinforcing fibers are blended by a method such as injection molding, so that the blending ratio of the reinforcing fibers is limited. However, in the fiber-reinforced plastic molded sheet of the present invention, the ratio of reinforcing fibers to matrix resin fibers can be set relatively freely according to the required strength.

  Moreover, it is preferable that 0.1-12 mass% is contained with respect to the total mass of the sheet | seat for fiber reinforced plastic moldings, and it is more preferable that a coupling agent is contained 0.5-10 mass%. The content is preferably 1 to 8% by mass. By adding the coupling agent so as to be in the above range, the strength of the fiber-reinforced plastic molded body can be further increased.

  JAPAN TAPPI Paper Pulp and Paper Test Method No. for Fiber Reinforced Plastic Molded Sheet The air permeability defined in 5-2 is preferably 250 seconds or less, more preferably 230 seconds or less, and even more preferably 200 seconds or less. This numerical value indicates that the smaller the number, the easier air can pass through (the better the air permeability). In the present invention, by setting the air permeability of the fiber-reinforced plastic molded sheet within the above range, the molding speed in the heating and pressing step can be increased, and the production efficiency can be increased.

  However, if the sheet before processing is adjusted to be bulky as a material for satisfying the above air permeability, there may be inconveniences when inserting the fiber reinforced plastic molded sheet into a heat press machine or the like in the heating and pressing step. There is. Moreover, there is also a problem that the storage cost is high until the sheet for fiber-reinforced plastic molded body is manufactured and used for the heating and pressing step. Such a problem can be solved by lightly pressing with a hot press or a heat calender before heat-press molding and appropriately increasing the density. In the case of this method, since air becomes somewhat difficult to pass, it is preferable to increase the density within a range in which the air permeability measured by a method based on the JAPAN TAPPI paper pulp test method can be maintained within a state of 250 seconds or less.

(Reinforced fiber)
The reinforcing fiber is preferably at least one selected from glass fiber, carbon fiber and aramid fiber. These reinforcing fibers may use only 1 type and may use multiple types. Moreover, you may contain the organic fiber excellent in heat resistance, such as a PBO (polyparaphenylene benzoxazole) fiber.

For example, when inorganic fiber such as carbon fiber or glass fiber is used as the reinforcing fiber, the fiber reinforced plastic molding is performed by heating and pressing at the melting temperature of the thermoplastic super engineering plastic fiber contained in the fiber reinforced plastic molded sheet. A body can be formed.
In addition, when high heat-resistant and high-strength organic fibers such as aramid fibers are used as reinforcing fibers, a fiber-reinforced plastic molded sheet suitable for precision polishing equipment that requires high smoothness is obtained. be able to. A fiber-reinforced plastic molded article formed from a fiber-reinforced plastic molded sheet containing organic fibers such as aramid as a reinforcing fiber is generally formed from a fiber-reinforced plastic molded sheet using inorganic fibers as the reinforcing fiber. It has better wear resistance than molded products. Even if a part of the fiber reinforced plastic body is scraped off by rubbing or the like, the shaving wrinkles are softer than the inorganic fibers, and therefore there is little risk of damaging the object to be polished.

  The fiber length of the reinforcing fibers is preferably 1 mm or more, more preferably 2 mm or more, and further preferably 3 mm or more. Further, the fiber length of the reinforcing fiber is preferably 40 mm or less, more preferably 35 mm or less, and further preferably 30 mm or less.

  Although it does not specifically limit as a fiber diameter of a reinforced fiber, 3-18 micrometers is preferable. By setting the fiber diameter of the reinforcing fiber within the above range, it can be prevented from being taken into the human body during the manufacturing process or during use, and can be mixed uniformly.

<Matrix resin fiber>
The matrix resin fibers include thermoplastic super engineering plastic fibers. The thermoplastic super engineering plastic fiber forms a binding point at the intersection of the matrix or fiber component during the heat and pressure treatment. Nonwoven fabric-reinforced plastic molded sheet using such matrix resin fibers does not require autoclaving and has shorter heat and pressure molding time than processing compared to sheet using thermosetting resin. You can increase your productivity in time.

  The thermoplastic super engineering plastic fiber is a fiber of a thermoplastic resin called a super engineering plastic (super engineering plastic), and is obtained by fiberizing a heat-resistant and flame-retardant thermoplastic resin. Examples of thermoplastic super engineering plastic fibers include polyetheretherketone (PEEK), polyamideimide (PAI), polyphenylene sulfide (PPS), polyetherimide (PEI), polyetherketoneketone (PEKK), and the like. Since polyphenylene sulfide (PPS) resin has high chemical resistance and high heat resistance, a fiber reinforced plastic excellent in chemical resistance and strength at high temperature can be obtained. When a polyether ketone ketone (PEKK) resin is used, a fiber reinforced plastic that is particularly superior in chemical resistance and strength at high temperatures than other super engineering plastics can be obtained. Polyetherimide (PEI) resin has excellent adhesion to carbon fiber and glass fiber, and its critical oxygen index is 47, which is very high in the resin block state. Can be obtained.

In the present invention, it is preferable to use at least one selected from polyetherimide (PEI) fiber or polycarbonate (PC) fiber as the thermoplastic super engineering plastic fiber. Among these, it is particularly preferable to use polyetherimide (PEI) fibers obtained by fiberizing a polyetherimide (PEI) resin. Polyetherimide (PEI) resin has a critical oxygen index of 40 or more in a melted and molded state, and a smoke generation amount of about 30 ds when burned for 20 minutes measured by the method described in ASTM E-662. It is preferably used because it emits less smoke.
Although not normally classified as a thermoplastic super engineering plastic fiber, polycarbonate (PC) is also included in the present invention because it is excellent in flame retardancy. Two or more kinds of the thermoplastic super engineering plastic fibers of the present invention can be used. Further, within the range not impairing the effect of the present invention, other than thermoplastic super engineering plastic fibers such as polyamide, polyacetal, polybutylene terephthalate, polyethylene terephthalate, phenol resin, polyurethane, polypropylene, polyethylene, epoxy resin, etc. can be added. .

The thermoplastic super engineering plastic fiber preferably has a critical oxygen index of 24 or more in the fiber state, and more preferably 30 or more. By setting the critical oxygen index of the thermoplastic super engineering plastic fiber within the above range, a fiber-reinforced plastic molded sheet excellent in flame retardancy can be obtained. In the present invention, the “limit oxygen index” represents an oxygen concentration necessary to continue combustion, and is a numerical value measured by the method described in JIS K7201. That is, a critical oxygen index of 20 or less is a numerical value indicating that combustion is performed in normal air. The polycarbonate has a limiting oxygen index of 24 to 26.
Moreover, it is preferable that the amount of smoke generated during the 20-minute combustion measured by the method described in ASTM E-662 of the thermoplastic super engineering plastic fiber is around 30 ds, and a sheet for fiber-reinforced plastic molded body having a very small amount of smoke is obtained. be able to.

  The glass transition temperature of the thermoplastic super engineering plastic fiber is preferably 140 ° C. or higher. The thermoplastic super engineering plastic fiber is required to be sufficiently fluid under a temperature condition of 300 ° C. to 400 ° C. when forming a fiber-reinforced plastic molded body. In addition, even if it is a super engineering plastic fiber with a glass transition temperature of less than 140 ° C. such as PPS resin fiber, it can be used as long as the super engineering plastic having a resin deflection temperature of 190 ° C. or higher is made into a fiber. Such thermoplastic super engineering plastic fibers are melted by heating and pressurizing to form a resin block having a very high flame retardancy with a limiting oxygen index of 30 or more.

  The fiber diameter of the thermoplastic super engineering plastic fiber is preferably 40 μm or less. Furthermore, the fiber diameter of the thermoplastic super engineering plastic fiber is preferably 5 times or less, more preferably 4 times or less, and still more preferably 3 times or less the fiber diameter of the above-mentioned reinforcing fiber. By setting the fiber diameter of the thermoplastic super engineering plastic fiber within the above range, the strength of the fiber-reinforced plastic molded body can be further increased.

  The fiber diameter of the thermoplastic super engineering plastic fiber is preferably 40 μm or less, more preferably 35 μm or less, and further preferably 32 μm or less. Especially, it is preferable that the fiber diameter of a thermoplastic super engineering plastic fiber is 1-30 micrometers, and it is more preferable that it is 1-20 micrometers.

  The fiber length of the thermoplastic super engineering plastic fiber is preferably 1 mm or more, more preferably 2 mm or more, and further preferably 3 mm or more. Further, the fiber length of the thermoplastic super engineering plastic fiber is preferably 40 mm or less, more preferably 35 mm or less, and further preferably 30 mm or less.

In the fiber-reinforced plastic molded sheet used in the present invention, there are voids in the sheet because the thermoplastic super engineering plastic fibers are in fiber form.
In the present invention, since the thermoplastic super engineering plastic fiber maintains its fiber form before heat-press molding, the sheet itself is supple and draped before the fiber-reinforced plastic molded body is formed. For this reason, it is possible to store and transport the sheet for a fiber-reinforced plastic molded body in the form of winding, and it is characterized by excellent handling properties.

  In addition, the sheet for a fiber-reinforced plastic molded body used in the present invention requires only a short time for heating and pressing when processed into a fiber-reinforced plastic molded body, and is excellent in productivity. In order to heat-press-mold a sheet for a fiber-reinforced plastic molded body in a short time, it is necessary that the thermoplastic super engineering plastic fiber used be melted quickly at a high temperature. Thinner fiber diameters are preferred. Since the number of contact points between fibers increases as the fiber diameter is thinner, the contact area between fibers increases, heat conduction becomes better, and the heat capacity of the fibers decreases, so the amount of heat required for melting is less It is to become.

<Coupling agent>
The coupling agent can form a strong bond between the reinforcing fiber and the matrix resin fiber. By using such a coupling agent, it is possible to obtain a sheet for a fiber-reinforced plastic molded body that can form a fiber-reinforced plastic molded body having excellent strength. Moreover, it can also suppress that a reinforced fiber falls off from the sheet | seat for fiber reinforced plastic moldings by using a coupling agent.

  Examples of the coupling agent include carboxylic acid-based, polymer-based, phosphoric acid-based, titanate, and silane coupling agents. In particular, it is preferable to add a silane coupling agent in view of its strength improving effect. In particular, a silane coupling agent having a functional group in the molecule is preferably used because it can be applied to a wide range of resins and has high reactivity. In this case, the silane coupling agent contains, as a functional group, a group selected from an amino group, vinyl group, epoxy group, styryl group, methacryloxy group, acryloxy group, ureido group, mercapto group, polysulfide group and isocyanate group. It is preferable that Especially, it is preferable to contain an amino group and an epoxy group as a functional group.

For example, specific examples of silane coupling agents having an epoxy group in the molecule include 3-glycidoxypropyltrimethoxysilane, 3-glycidoxypropyltriethoxysilane, and 3-glycidoxypropylmethyldimethoxy. Silane, 3-glycidoxypropylmethyldiethoxysilane, 2- (3,4-epoxycyclohexyl) ethyltrimethoxysilane, 2- (3,4-epoxycyclohexyl) ethyltriethoxysilane, 2- (3,4- (Epoxycyclohexyl) ethylmethyldimethoxysilane and the like.
Specific examples of the silane coupling agent having an amino group in the molecule include N-2- (aminoethyl) -3-aminopropylmethyldimethoxysilane, N-2- (aminoethyl) -3- Aminopropyltrimethoxysilane, N-2- (aminoethyl) -3-aminopropyltriethoxysilane, 3-aminopropyltrimethoxysilane, 3-aminopropyltriethoxysilane, 3-triethoxysilyl-N- (1, Examples thereof include 3-dimethyl-butylidene) propylamine, N-phenyl-3-aminopropyltrimethoxysilane, and N- (vinylbenzyl) -2-aminoethyl-3-aminopropyltrimethoxysilane hydrochloride.

  The coupling agent is preferably contained in an amount of 0.1 to 12% by mass, more preferably 0.5 to 10% by mass, based on the total mass of the fiber-reinforced plastic molded sheet. It is more preferable that 1-8 mass% is contained. By adding the coupling agent so as to be in the above range, the strength of the fiber-reinforced plastic molded body can be further increased. In addition, a merit in terms of cost can be obtained.

  The mixing method of the coupling agent is not particularly limited. For example, an internal addition method (wet method), an impregnation method, a dispenser coating method, a spin coating method, a knife coating method, a slit coating method, an inkjet coating method, a screen printing method, Examples include an offset printing method or a die coating method.

<Binder component>
The fiber-reinforced plastic molded sheet further contains a binder component. Examples of binders that can be used include thermosetting resins such as phenolic resins, urea resins, melamine resins, unsaturated polyester resins, epoxy resins, and silicon resins that are commonly used in nonwoven fabric production, polypropylene resins, polyethylene resins, and polyesters. Resin, acrylic resin, styrene-acrylic resin, ethylene-vinyl acetate resin, urethane resin and other thermoplastic resins, hot water-melting PVA resin, and the like can be used.

  The binder component is particularly preferably a resin component that is compatible with the resin when the thermoplastic super engineering plastic fiber that becomes the matrix after heat-pressure molding is melted by heat-pressure molding. When such a resin component is used as a binder, there is no interface between the matrix resin and the binder resin after the heat and pressure molding, and therefore the strength is increased. Furthermore, it has the characteristic that there is little fall of the glass transition temperature of matrix resin resulting from a binder component.

  In this invention, it is preferable to contain a binder component so that it may become 0.1-10 mass% with respect to the total mass of the sheet | seat for fiber reinforced plastic moldings, and is 0.4-9.5 mass%. It is more preferable, and it is still more preferable that it is 0.5-8 mass%. By making the content rate of a binder component in the said range, the intensity | strength in a manufacturing process can be raised and handling property can be improved. Note that as the amount of the binder component increases, both the surface strength and the interlayer strength increase, but conversely, the problem of odor during heat forming tends to occur. However, within the above range, there is hardly any problem of odor, and a fiber reinforced plastic molded sheet that does not cause delamination even after repeated cutting steps can be obtained.

A preferable binder component in the present invention includes a copolymer obtained by polymerizing a monomer mixture containing at least one monomer of methyl methacrylate, ethyl methacrylate, methyl acrylate and ethyl acrylate. As said copolymer, the copolymer containing at least 1 among the repeating unit derived from a methyl (meth) acrylate containing monomer and the repeating unit derived from an ethyl (meth) acrylate containing monomer is contained. Especially, it is preferable to contain the copolymer containing at least 1 among the repeating unit derived from a methyl methacrylate containing monomer, and the repeating unit derived from an ethyl methacrylate containing monomer.
In the present invention, “(meth) acrylate” means containing both “acrylate” and “methacrylate”, and “(meth) acrylic acid” means “acrylic acid” and “methacrylic acid”. Is meant to include both.

  Furthermore, a binder component having a melting point lower than the glass transition temperature of the thermoplastic super engineering plastic fiber is mentioned as a preferable binder component in the present invention. When the binder fiber is mixed with thermoplastic super engineering plastic fiber and dispersed in water and made by wet papermaking, it drops from the eyes of the papermaking wire like a granular binder, and the yield decreases or is unevenly distributed on the wire side. It is preferably used because it does not occur. Moreover, interlayer strength can be improved by using such a binder fiber.

As the binder fiber, a polyester resin is preferably used. As the polyester resin, polyethylene terephthalate (PET) is preferable. The modified polyester resin is not particularly limited as long as the melting point is lowered by modifying the polyester resin, but modified polyethylene terephthalate is preferable. As the modified polyethylene terephthalate, copolymerized polyethylene terephthalate (CoPET) is preferable, and examples thereof include urethane-modified copolymerized polyethylene terephthalate. Since the polyester resin is compatible with the polyetherimide fiber at the time of heat-melting, it is preferably used because it is difficult to impair the function of heat and resin even after cooling.
The copolymerized polyethylene terephthalate preferably has a melting point of 140 ° C. or lower, more preferably 120 ° C. or lower. Moreover, you may use the modified polyester resin as described in Japanese Patent Publication No. 1-30926. As a specific example of the modified polyester resin, a trade name “Melty 4000” (a fiber in which all fibers are copolymerized polyethylene terephthalate) manufactured by Unitika Ltd. is particularly preferable. As the core-sheath-structured binder fiber, trade name “Melty 4080” manufactured by Unitika Co., Ltd., trade name “N-720” manufactured by Kuraray Co., Ltd. and the like can be suitably used.

Copolymers obtained by polymerizing a monomer mixture containing at least one monomer of methyl methacrylate, ethyl methacrylate, methyl acrylate and ethyl acrylate, and binder fibers such as polyester resin fibers should be used alone. However, it can also be used in combination to further improve the effects of the present invention.
The copolymer is contained in an amount of 0.1 to 4% by mass based on the total mass of the fiber-reinforced plastic molded sheet, and the binder fiber is 1.5% based on the total mass of the fiber-reinforced plastic molded sheet. It is preferable to contain so that it may become -6 mass%.
By making the content rate of a copolymer and a binder fiber into the said range, the surface strength and interlayer intensity | strength of a sheet | seat for fiber reinforced plastic molding can be raised. In addition, in said range, a preferable result is obtained from the relationship of an odor, when the compounding quantity of the binder which uses a copolymer as a component (liquid binder) is smaller than a polyester resin or a modified polyester resin. Since the polyester binder is compatible with the matrix resin, it is difficult to generate odor even if the addition amount is relatively large, and since the liquid binder tends to be concentrated and concentrated at the intersection of the fibers, such a result is obtained. Estimated.

  A preferable combination as the binder component is a combination of an acrylic emulsion and a chopped PET fiber as a low melting point thermoplastic resin fiber. Specifically, it is 1.5-6 mass% of PET fiber with respect to 0.3-4 mass% of acrylic binder with respect to the total mass of the sheet | seat for fiber reinforced plastic moldings. Preferably, it is 2 to 6% by mass of PET fiber with respect to 1 to 3% by mass of acrylic binder, and more preferably 3 to 5% by mass of PET fiber with respect to 1.5 to 2.5% by mass of acrylic binder.

When the sheet for fiber-reinforced plastic molded body has a sheet shape having an intermediate region sandwiched between the surface layer region and the surface layer region, the binder component contained in the surface layer region is greater than the binder component contained in the intermediate region. Is preferred. In particular, among the binder components, a copolymer containing at least one of a repeating unit derived from a methyl (meth) acrylate-containing monomer and a repeating unit derived from an ethyl (meth) acrylate-containing monomer may be contained in a large amount in the surface layer region. preferable.
Here, the surface layer area | region of the sheet | seat for fiber reinforced plastic moldings is two area | regions located outside, when dividing the sheet | seat sheet for fiber reinforced plastics moldings into the thickness direction (Z-axis direction) about three. Note that the intermediate region refers to a region between these two regions. The binder component contained in the surface layer region is preferably more than the binder component contained in the intermediate region, and the binder component contained in the surface layer region is 1.1 of the binder component contained in the intermediate region. It is more preferable to be -1.5 times.

  In this way, by concentrating the binder component in the surface layer region, the binder component is effectively heated when it is heated and pressed by a high-temperature mold or press plate.・ Volatile. As a result, the binder component remaining in the thermoformed product is suppressed to a very small amount. For this reason, in the sheet | seat for fiber reinforced plastic moldings of this invention, the function of a thermoplastic super engineering plastic fiber can fully be exhibited.

  A liquid binder composed of a copolymer of a monomer mixture containing at least one monomer selected from methyl methacrylate, ethyl methacrylate, ethyl acrylate, and methyl acrylate is concentrated in the surface layer region of the sheet for fiber-reinforced plastic molding. It is preferable. Moreover, it is preferable that these liquid binders are localized in the form of a drainage film at the intersection between the fiber components in both surface layer regions. That is, it is preferable that the copolymer be localized in the form of a water squeezing film at the intersection between the fibers constituting the reinforcing fiber and the matrix resin fiber. By being localized in this manner, even if the binder component is small, even in the use process, the fibers falling off in both surface layer regions can be reduced. Moreover, it is suitable for the process which cuts and laminates | stacks on a flat plate immediately after papermaking of the sheet | seat for fiber reinforced plastic moldings, and presses suitably.

  In addition, although it is preferable to concentrate the component containing a copolymer in a surface layer area | region among binder components, binder fiber can also be contained in the intermediate | middle area | region of the sheet | seat for fiber reinforced plastic moldings. Thereby, the interlayer intensity | strength of the sheet | seat for fiber reinforced plastic moldings increases, and the handling property at the time of a thermoforming process is further improved.

  The binder fiber can be contained in the fiber-reinforced plastic molded sheet by a method (dry nonwoven fabric method) in which the binder fiber is dispersed in the air together with the reinforcing fiber, the matrix resin fiber, etc., and captured on the net to form a web. The binder fiber can also be contained in the fiber-reinforced plastic molded sheet by a method such as a method (wet nonwoven fabric method) in which the binder fiber is dispersed in a solvent and then the solvent is removed to form a web.

  Examples of the method for allowing a relatively large amount of the binder to be present in the surface layer of the fiber reinforced plastic molded sheet include the following methods. For example, a production method in which a liquid material in which a binder component is dissolved in a solvent or an emulsion (emulsion) of a binder component is internally added to, applied to, or impregnated into a nonwoven fabric sheet, and is heated and dried. In particular, after a web is formed by a wet nonwoven fabric method or a dry nonwoven fabric method, a liquid material in which a binder component is dissolved in a solvent, or an emulsion (emulsion) of a binder component is applied by dipping or spraying, and dried by heating. The production method is preferably used. According to this method, since the solvent inside the web moves to the surface layers on both sides and evaporates during heating and drying, the binder also concentrates relatively on the surface layer as the solvent moves.

As described above, in order to make the binder component unevenly distributed on the surface layer of the fiber-reinforced plastic molded sheet, a manufacturing method in which a liquid binder component such as a solution or an emulsion of the binder component is used and dried by heating is employed. Can do. In this case, it is preferable that the solvent move more because the uneven distribution of the binder component becomes stronger.
When such a method is employed, it is preferable to form a wet web by a wet nonwoven fabric method, and then apply an aqueous solution or emulsion of the binder to the web by a method such as dipping or spraying, followed by drying. In this case, the web moisture can be adjusted by adjusting the concentration of the binder solution in the aqueous solution or emulsion, or the moisture suction force by wet suction or dry suction in the wet nonwoven fabric manufacturing process.

  In order to make the binder component unevenly distributed, the moisture content in the web is preferably 50% or more, but if there is too much moisture, the drying load increases and the manufacturing cost increases. Is preferably adjusted.

When the above measures are insufficient, it is also preferable to wet-paper the fiber-reinforced plastic molded sheet to increase the strength aspect ratio as a method of reducing the amount of binder component added. Specifically, the strength ratio (strength aspect ratio) of the machine-making direction (MD direction) and the perpendicular direction (CD direction) can be increased by adjusting the jet wire ratio. In general, when the strength aspect ratio is increased, the fibers tend to line up in one direction, and the density of the nonwoven fabric tends to increase. As a result, the intersections between the fibers increase, so that a sufficient surface strength can be obtained even with a small amount of binder. Such an effect can be clearly obtained usually when the strength aspect ratio is 1.5 or more, more clearly is 3.0 or more, and more clearly is 5.0 or more.
On the other hand, if the strength aspect ratio is too strong, the transverse strength becomes weak and the handling property is poor. Considering this point, the preferred strength aspect ratio is 15 or less, more preferably 10 or less.

(Fiber shape)
In the present invention, the thermoplastic super engineering plastic fiber and the reinforcing fiber are preferably chopped strands cut to a certain length. The binder fiber is also preferably chopped strand. By setting it as such a form, various fibers can be mixed uniformly in the sheet | seat for fiber reinforced plastic moldings.

  In the above case, the fiber reinforced plastic molded sheet is a method of forming a web by dispersing chopped strands of thermoplastic super engineering plastic fibers, reinforcing fibers and binder fibers in the air and capturing them in a net (dry nonwoven fabric). Method). Further, it may be produced by a method (wet nonwoven fabric method) or the like in which a chopped strand of thermoplastic super engineering plastic fiber, reinforcing fiber, or binder fiber is dispersed in a solvent and then the solvent is removed to form a web.

(Fiber reinforced plastic molding)
The sheet for a fiber-reinforced plastic molded body of the present invention can be processed into an arbitrary shape according to the shape and molding method of a target molded product, thereby forming a molded body. The sheet for fiber reinforced plastic molded body is singly or laminated to have a desired thickness, and heat-pressed by hot press, or preheated by an infrared heater in advance, and heat-pressed by a mold. be able to. Thus, the fiber reinforced plastic molding excellent in intensity | strength can be made by processing using the heat stamping method of a general stampable sheet.

  In the present invention, when producing a fiber reinforced plastic molded body from a fiber reinforced plastic molded sheet, the fiber reinforced plastic molded sheet is subjected to pressure heating molding at a temperature equal to or higher than the glass transition temperature of the thermoplastic super engineering plastic fiber. It is preferable to do. For example, the conditions for the molding process by hot pressing vary depending on the thermoplastic resin used, but the temperature is 150 to 600 ° C, more preferably 200 to 500 ° C, still more preferably 250 to 450 ° C, and the pressure is 5 to 5. 20 MPa is preferred. Further, the rate of temperature rise until reaching the desired holding temperature is preferably 3 to 20 ° C./min. The holding time at the desired hot press temperature is 1 to 30 minutes, and then the temperature at which the molded body is taken out (200 ° C. It is preferable to set it as a cooling rate of 3-20 degree-C / min, maintaining a pressure until below. Furthermore, although the production efficiency is slightly lowered, it is also preferable from the viewpoint of improving the strength to cool slowly by air cooling from the holding temperature of the hot press to the glass transition temperature of the super engineering plastic fiber at 0.1 to 3 ° C./min. It is also possible to perform hot press molding using rapid heating and rapid cooling (heat and cool) molding, in which case the temperature rise and cooling rate are 30 to 500 ° C./min, respectively. Furthermore, in the case of using an infrared heater, the temperature is 150 to 600 ° C., preferably 200 to 500 ° C., for 1 to 30 minutes, and then molded at a pressure of 30 to 150 MPa.

  Since the plastic molded product obtained by the present invention has excellent mechanical strength and industrially useful productivity, it can be used in various applications.

(Method for producing sheet for fiber-reinforced plastic molded body)
The process for producing the sheet for fiber-reinforced plastic molded body of the present invention comprises the steps of mixing a reinforcing fiber, a matrix resin fiber containing a thermoplastic super engineering plastic fiber, a binder component, and a coupling agent, and a dry nonwoven fabric method or a wet nonwoven fabric method. The process of forming a nonwoven fabric sheet is included. The critical oxygen index of the thermoplastic super engineering plastic fiber used in this production process is 24 or more. The fiber diameter of the thermoplastic super engineering plastic fiber is preferably 40 μm or less, and the fiber diameter of the thermoplastic super engineering plastic fiber is preferably 5 times or less of the fiber diameter of the reinforcing fiber.

  In the present invention, it is preferable that the step of forming the nonwoven fabric sheet includes a step of internally adding, applying or impregnating the nonwoven fabric sheet with a solution containing the binder component or an emulsion containing the binder component, followed by heating and drying. That is, the step of forming the sheet for fiber reinforced plastic molded body includes the step of forming the nonwoven fabric sheet by either the dry nonwoven fabric method or the wet nonwoven fabric method, and internally adding and applying a solution containing a binder component to the nonwoven fabric sheet. Alternatively, it is preferable to include an impregnation step. Further, after the internal addition, coating or impregnation, a step of drying by heating is included. By providing such a process, it is possible to suppress the scattering, fluffing and dropping off of the surface fibers of the nonwoven fabric sheet for fiber-reinforced plastic molded body, and to obtain a sheet for fiber-reinforced plastic molded body having excellent handling properties. .

  In addition, after the solution containing a binder component or the emulsion containing a binder component is internally added, applied, or impregnated to the nonwoven fabric sheet, it is preferable to rapidly heat the nonwoven fabric sheet. By providing such a heating step, the solution containing the binder component or the emulsion containing the binder component can be transferred to the surface layer region of the sheet for fiber-reinforced plastic molded body. In addition, the binder component can be localized in the form of a water scraping film.

  The step of forming the nonwoven fabric sheet may include a step of adding a coupling agent by a spray method. When the coupling agent is added by a spray method, a predetermined amount of the coupling agent is added to the web obtained by wet or dry papermaking by spraying.

  Moreover, the process of forming a nonwoven fabric sheet may include the process of adding a coupling agent by an internal addition method. When the coupling agent is added internally (wet method), the matrix fiber containing the reinforcing fiber and the thermoplastic super engineering plastic fiber is dispersed in water to form a slurry of about 0.1 to 5%, and the cup is then added to it. A predetermined amount of a ring agent is added and mixed with stirring. A wet web is formed by the wet papermaking method, and the slurry is heated and dried to obtain a nonwoven fabric sheet.

  Furthermore, the process of forming a nonwoven fabric sheet is a process of heat-treating a nonwoven fabric sheet having a reinforcing fiber component and matrix resin fibers made of thermoplastic super engineering plastic fibers at a temperature equal to or higher than the glass transition temperature of the thermoplastic super engineering plastic fibers. You may have. Thereby, scattering, fluffing, and dropping off of the surface fibers can be suppressed, and a sheet for a fiber-reinforced plastic molded body having excellent handling properties can be obtained.

The features of the present invention will be described more specifically with reference to examples and comparative examples. The materials, amounts used, ratios, processing details, processing procedures, and the like shown in the following examples can be changed as appropriate without departing from the spirit of the present invention. Therefore, the scope of the present invention should not be construed as being limited by the specific examples shown below. In each production example, “part” and “%” represent “part by mass” and “% by mass” unless otherwise specified. In addition, below, Examples 1-6, 12, 12-14, 18-27 shall be read as Reference Examples 1-6, 8, 12-14, 18-27, respectively.

Example 1
A PAN-based carbon fiber having a fiber diameter of 7 μm and a fiber length of 13 mm, and a PPS resin fiber having a fiber diameter shown in Table 1 (manufactured by Fiber Innovation Technology, fiber length of 13 mm, critical oxygen index of 41) and a mass ratio of polyacrylonitrile (PAN) ) It measured so that it might become the polyphenylene sulfide (PPS) resin fiber 60 with respect to the system carbon fiber 40, and thrown in water. The amount of water added was set to be 200 times the total mass of the PAN-based carbon fiber and the PPS resin fiber (that is, the fiber slurry concentration was 0.5%).
To this slurry, the trade name “Emanon 3199” (manufactured by Kao Corporation) is added as a dispersant to 1 part by mass with respect to 100 parts by mass of the fiber (total of PAN-based carbon fiber and PPS fiber), and the fiber is stirred in water A fiber slurry dispersed uniformly was prepared.

Next, granular polyvinyl alcohol (PVA) shown in Table 1 (product name “OV-N”, manufactured by Unitika Co., Ltd.) was added to water so as to have a concentration of 10%, and stirred to prepare a binder slurry. The granular PVA 10% concentration slurry and aminosilane coupling agent (manufactured by Shin-Etsu Silicone Co., Ltd., trade name “KBM-603”) are added to the fiber slurry at the blending ratio shown in Table 1, and the wet web making method is used. After forming and heat-drying at 180 ° C., by heating and pressurizing with a heat press at 220 ° C., the basis weight that gives the air permeability shown in Table 1 is 250 g / m ^2. A sheet was obtained. The obtained fiber reinforced plastic molded sheet was made using the JAPAN TAPPI paper pulp test method No. The air permeability specified in 5-2 was 195 seconds.

(Examples 2 and 3)
In Example 2, the air permeability was adjusted as shown in Table 1 by shortening the heating and pressing time and lowering the density as compared with Example 1.
In Example 3, a fiber-reinforced plastic molded sheet was obtained in the same manner as in Example 1 except that the amount of binder added was 12% by mass.
In addition, the addition amount of granular PVA slurry density | concentration was adjusted suitably so that the compounding rate with respect to the sheet | seat for fiber reinforced plastic moldings of granular PVA may become as showing in Table 1.

Example 4
Except for changing the PPS resin fiber to the PPS fiber having the fiber diameter shown in Table 1 (KB Selen, glass transition temperature 92 ° C., fiber length 13 mm, critical oxygen index 41), the same procedure as in Example 1 was performed. A sheet for a fiber-reinforced plastic molded body was produced.

(Examples 5-7)
The PAN-based carbon fiber having a fiber diameter of 7 μm and a fiber length of 13 mm in Example 1 was changed to a glass fiber having a fiber diameter of 9 μm and a fiber length of 18 mm, and the PPS resin fiber in Example 1 (manufactured by Fiber Innovation Technology) The glass transition temperature 92 ° C. and the limiting oxygen index 41) were changed to the polyetherimide (PEI) resin fibers shown in Table 2 (Fiber Innovation Technology, glass transition temperature 220 ° C., fiber length 13 mm, limiting oxygen index 47). A nonwoven fabric having a basis weight of 250 g / m ² was obtained in the same manner as in Example 1 except that. The obtained sheet was heated and pressed by a hot press at 280 ° C. to appropriately adjust the air permeability as shown in Table 2, and the fiber-reinforced plastic molded body sheets of Examples 5 and 6 were produced. In Example 6, the air permeability was adjusted as shown in Table 2 by shortening the heating and pressing time by 2820 ° C. hot pressing and lowering the density as compared with Example 5.
Moreover, except having changed granular PVA (the product name "OV-N" by Unitika Co., Ltd.) into the PET / coPET modified core-sheath binder fiber (product name "Melty 4080" by Unitika), it is the same as Example 5. Thus, a fiber-reinforced plastic molded sheet for Example 7 was produced.

(Examples 8 to 13)
The PPS resin fiber in Example 1 was replaced with a PPS resin fiber having a fiber diameter of 16 μm (manufactured by Fiber Innovation Technology, glass transition temperature 92 ° C., fiber length 13 mm, critical oxygen index 41), and instead of granular PVA, a wet web was used. After the formation, the fiber solution of Examples 8 to 13 was added in the same manner as in Example 1 except that the binder liquid and silane coupling agent shown in Table 3 were added by the spray method in the amounts shown in Table 3 and dried by heating. A sheet for plastic molding was produced. In addition, the conditions of 220 degreeC hot press were adjusted suitably so that the air permeability of Table 3 might be obtained.

(Examples 14 to 19)
Examples 8 to 13 except that the PPS resin fibers in Examples 8 to 13 are replaced with PEI resin fibers having a fiber diameter of 15 μm (manufactured by Fiber Innovation Technology, glass transition temperature 220 ° C., fiber length 13 mm, critical oxygen index 47). The sheet | seat for fiber reinforced plastic moldings of Examples 14-19 corresponding to each of these was produced.

  In the above binder solution, a PVA aqueous solution in which Kuraray's trade name “PVA117” was dissolved in hot water was used. Moreover, the brand name "GM-1000" by DIC was used for the styrene-acrylic emulsion, and the brand name "AP-X101" by DIC was used for the urethane emulsion.

(Example 20)
A polycarbonate fiber (fiber length 15 mm, fiber diameter 30 μm, critical oxygen index 25) was used in place of the PEI fiber having a fiber diameter of 15 μm in Example 14 (manufactured by Fiber Innovation Technology, fiber length 13 mm, critical oxygen index 47). In the same manner as in Example 14, a fiber-reinforced plastic molded sheet was obtained.

(Example 21)
Polycarbonate fiber (fiber length 15 mm, fiber diameter 30 μm, critical oxygen index 25) and PEI fiber (fiber innovation technology, fiber length 13 mm, critical oxygen index 47) having a fiber diameter of 15 μm were mixed at a mass ratio of 50/50. A fiber-reinforced plastic molded sheet was obtained in the same manner as in Example 14 except that it was used.

(Example 22)
Except that the aminosilane type coupling agent (trade name “KBM-603” manufactured by Shin-Etsu Silicone Co., Ltd.) was replaced with the epoxy silane type coupling agent (trade name “KBM-303” manufactured by Shin-Etsu Silicone Co., Ltd.). In the same manner as in Example 14, a fiber-reinforced plastic molded sheet was produced.

(Example 23)
Except for replacing the aminosilane type coupling agent (trade name “KBM-603”, manufactured by Shin-Etsu Silicone Co., Ltd.) with the styrylsilane type coupling agent (trade name “KBM-403”, manufactured by Shin-Etsu Silicone), In the same manner as in Example 14, a fiber-reinforced plastic molded sheet was produced.

(Example 24)
The aminosilane type coupling agent (trade name “KBM-603” manufactured by Shin-Etsu Silicone Co., Ltd.) was replaced with a methacryloxysilane type coupling agent (trade name “KBM-503” manufactured by Shin-Etsu Silicone Co., Ltd.). In the same manner as in Example 14, a fiber-reinforced plastic molded sheet was produced.

(Example 25)
The aminosilane type coupling agent (trade name “KBM-603”, manufactured by Shin-Etsu Silicone) was replaced with an acryloxysilane type coupling agent (trade name “KBM-5103”, manufactured by Shin-Etsu Silicone). In the same manner as in Example 14, a fiber-reinforced plastic molded sheet was produced.

(Example 26)
A fiber-reinforced plastic molded sheet was prepared in the same manner as in Example 14 except that the amount of the aminosilane-type coupling agent (trade name “KBM-603”, manufactured by Shin-Etsu Silicone Co., Ltd.) was 2.0%. did.

(Example 27)
A fiber-reinforced plastic molded sheet was prepared in the same manner as in Example 14, except that the amount of the aminosilane-type coupling agent (trade name “KBM-603”, manufactured by Shin-Etsu Silicone Co., Ltd.) was 8.0%. did.

(Comparative Example 1)
A fiber reinforced plastic molded sheet was prepared in the same manner as in Example 1 except that the aminosilane type coupling agent (trade name “KBM-603”, manufactured by Shin-Etsu Silicone Co., Ltd.) was not added.

(Comparative Example 2)
In Example 1, instead of PPS resin fibers (manufactured by Fiber Innovation Technology, fiber length 13 mm, critical oxygen index 41), polyamide 6 resin (manufactured by Toray Industries, Inc., trade name “Amilan CM1021”, melting point 210 ° C., limiting oxygen index 20 A fiber reinforced plastic molded sheet was produced in the same manner as in Example 1 except that the fiber diameter was changed to 20 μm.

(Comparative Example 3)
A fiber reinforced plastic molded sheet was prepared in the same manner as in Example 5 except that the aminosilane type coupling agent (trade name “KBM-603”, manufactured by Shin-Etsu Silicone Co., Ltd.) was not added.

(Comparative Example 4)
A fiber reinforced plastic molded sheet was prepared in the same manner as in Example 8 except that the aminosilane type coupling agent (trade name “KBM-603”, manufactured by Shin-Etsu Silicone Co., Ltd.) was not added.

  Six sheets for each fiber-reinforced plastic molded body obtained in each of the above Examples and Comparative Examples were laminated, inserted into a hot press preheated to 310 ° C., heated and pressurized for 60 seconds, and then cooled to 230 ° C. Thus, a fiber-reinforced plastic molded body was obtained.

(Evaluation)
(appearance)
The appearance of the obtained fiber reinforced plastic molding was evaluated according to the following criteria.
◎: Good with no voids, etc. ○: Slightly voids can be confirmed △: Voids are generated but there is no practical problem ×: Appearance is clearly poor due to voids and cannot be used as a product

(Strength)
About bending strength, it measured by the method based on JISK7074 about the obtained fiber reinforced plastic body.

(Limited oxygen index)
The critical oxygen index (LOI value) was calculated by performing a flame retardancy test based on the JIS K7201 method.

  In Examples 1-27, it turns out that the bending strength and flame retardance (limit oxygen index) of a fiber reinforced plastic molding are high, both balance is good, and it is excellent. On the other hand, in Comparative Examples 1, 3, and 4, the bending strength is low. On the other hand, in Comparative Example 2, although the strength is obtained to some extent, the flame retardance is inferior.

  According to the present invention, a fiber reinforced plastic molded article having excellent strength and flame retardancy can be obtained. Furthermore, if the sheet | seat for fiber reinforced plastic moldings of this invention is used, it will become possible to produce a fiber reinforced plastic molding continuously efficiently, and industrial applicability is high in various manufacturing industries using fiber reinforced plastics. .

Claims (17)

Containing reinforcing fiber, matrix resin fiber including thermoplastic super engineering plastic fiber, binder component, and coupling agent,
Limiting oxygen index of the thermoplastic super engineering plastic fiber Ri der 24 or more,
The binder component is at least one selected from a styrene-acrylic resin, a urethane resin, and a polyester resin .   The sheet for fiber-reinforced plastic molded bodies according to claim 1, wherein the reinforcing fibers are at least one selected from glass fibers, carbon fibers, and aramid fibers.   3. The fiber diameter of the thermoplastic super engineering plastic fiber is 40 μm or less, and the fiber diameter of the thermoplastic super engineering plastic fiber is 5 times or less of the fiber diameter of the reinforcing fiber. 4. Sheet for fiber reinforced plastic moldings.   The fiber-reinforced plastic molded sheet according to any one of claims 1 to 3, wherein the thermoplastic super engineering plastic fiber is at least one selected from polyetherimide fiber or polycarbonate fiber.   The sheet for fiber-reinforced plastic molded body according to any one of claims 1 to 4, wherein the thermoplastic super engineering plastic fiber is a polyetherimide (PEI) fiber.   JAPAN TAPPI Paper Pulp Test Method No. The sheet for a fiber-reinforced plastic molded body according to any one of claims 1 to 5, wherein the air permeability defined in 5-2 is 250 seconds or less.   The sheet for fiber-reinforced plastic molded body according to any one of claims 1 to 6, wherein the thermoplastic super engineering plastic fiber and the reinforcing fiber are chopped strands.   The said coupling agent is a silane coupling agent, The sheet | seat for fiber reinforced plastic moldings of any one of Claims 1-7 characterized by the above-mentioned.   The silane coupling agent contains, as a functional group, a group selected from an amino group, vinyl group, epoxy group, styryl group, methacryloxy group, acryloxy group, ureido group, mercapto group, polysulfide group and isocyanate group. The sheet for fiber-reinforced plastic molded bodies according to claim 8.   The fiber reinforced according to any one of claims 1 to 9, wherein the binder component is contained in an amount of 0.1 to 10% by mass with respect to the total mass of the fiber reinforced plastic molded sheet. Plastic molded sheet.   The said binder component is compatible with the said thermoplastic super engineering plastic fiber in a heat-melting state, The sheet | seat for fiber reinforced plastic moldings of any one of Claims 1-10 characterized by the above-mentioned. The sheet for fiber-reinforced plastic molded body has a surface layer region and an intermediate region sandwiched between the surface layer region,
The fiber-reinforced plastic molded sheet according to any one of claims 1 to 11 , wherein the binder component contained in the surface layer region is greater than the binder component contained in the intermediate region. The fiber reinforcement according to any one of claims 1 to 12 , wherein the binder component is localized in the form of a drainage film at an intersection of the fibers constituting the reinforcing fiber and the matrix resin fiber. Plastic molded sheet. For fiber reinforced plastic molded products including a step of mixing a reinforcing fiber, a matrix resin fiber containing a thermoplastic super engineering plastic fiber, a binder component, and a coupling agent, and forming a nonwoven fabric sheet by a dry nonwoven fabric method or a wet nonwoven fabric method In the sheet manufacturing method,
Limiting oxygen index of the thermoplastic super engineering plastic fiber Ri der 24 or more,
The said binder component is at least 1 sort (s) selected from a styrene-acrylic resin, a urethane resin, and a polyester resin , The manufacturing method of the sheet | seat for fiber reinforced plastic moldings characterized by the above-mentioned. The step of forming the nonwoven sheet, an emulsion containing the solution or binder component comprising a binder component in the nonwoven fabric sheet internally added, is coated or impregnated, according to claim 14, characterized in that it comprises a step of heating and drying A method for producing a sheet for a fiber-reinforced plastic molded body. The fiber-reinforced plastic molded body sheet according to any one of claims 1 to 13 and characterized in that it is formed by heat and pressure molding at a temperature above the glass transition temperature of the thermoplastic super engineering plastic fiber Fiber reinforced plastic molding. A fiber-reinforced plastic molded body, which is formed by heat-pressing the sheet for fiber-reinforced plastic molded body according to any one of claims 1 to 13 at a temperature of 150 to 600 ° C. .