JP2019001004A - Fiber composite - Google Patents

Abstract

To provide a fiber composite capable of obtaining rigidity under a high-temperature environment, and an aesthetic appearance.SOLUTION: There is provided a fiber composite, which is the fiber composite containing a core material containing a resin foam, and formed by laminating a skin material containing a fiber and a resin on at least a part of a surface of the core material. In a cross section in a thickness direction of the fiber composite, a resin part (A) having a width of 8 μm or more, and bubbles (C) having an average major axis of 5-800 μm are contained in the core material.SELECTED DRAWING: Figure 1

Description

  The present invention relates to a fiber composite. More specifically, the present invention relates to a fiber composite having excellent strength in a high temperature environment.

  Since fiber reinforced synthetic resin reinforced with fibers is lightweight and has high mechanical strength, in recent years, light weight and high mechanical strength are required in the automotive field, ship field, aviation field, medical field, etc. The use is expanding in the fields that are being used.

  As a composite with fiber-reinforced synthetic resin, a fiber composite is proposed in which foam is used for the core material and fiber-reinforced synthetic resin is laminated and integrated on the surface of the core material for the purpose of reducing weight and improving heat insulation. (See Patent Documents 1 and 2).

  Further, it has been proposed to use a heat-resistant resin such as polyamide resin or polyethylene terephthalate resin for the foam of the core material (see Patent Documents 3 and 4).

Japanese Patent Laying-Open No. 2015-83365 JP 2005-313613 A JP 2014-208417 A JP 2013-188953 A

  In recent years, there has been an increasing demand for fiber composites that can withstand use in higher temperature environments and for shortening their molding cycles.

  However, the fiber composite of Patent Document 1 is composed of a core material having a cellular structure and a surface material made of a thermoplastic resin and carbon fiber, but it is not possible to obtain a fiber composite having good rigidity in a high temperature environment such as 100 ° C. difficult.

  The composite of Patent Document 2 defines the strength of the reinforcing fibers in the skin material, and is high in strength at room temperature, but it is possible to obtain a fiber composite having good rigidity in a high temperature environment such as 100 ° C. difficult.

  The fiber composite of Patent Document 3 uses a polyamide foam sheet having high heat resistance for the foamed resin, and the polyethylene terephthalate foam having high heat resistance is used for the fiber composite of Patent Document 4, but in an environment of 100 ° C. The bending strength is still insufficient.

  Then, an object of this invention is to provide the fiber composite_body | complex which can obtain the rigidity in the environment of high temperature (for example, 100 degreeC), and the aesthetic appearance.

  In order to solve the above problems, the present inventors are a fiber composite in which a skin material containing fibers and a resin is laminated on at least a part of the surface of a core material, and the cross section in the thickness direction of the fiber composite By including a resin portion having a specific width or more and bubbles having an average cell ratio in a specific range in the core material, excellent rigidity and aesthetic appearance in a high temperature environment (for example, 100 ° C.) can be obtained. As a result, the inventors have made the present invention.

That is, the present invention is as follows.
(1)
A fiber composite comprising a core material containing a foamed resin, and a skin material containing fibers and resin laminated on at least a part of the surface of the core material;
In the cross section in the thickness direction of the fiber composite, the core includes a resin portion (A) having a width of 8 μm or more and bubbles (C) having an average major axis of 5 to 800 μm. .

(2)
The fiber composite according to (1), wherein in the cross section, at least a part of the resin portion (A) is continuously connected from one surface of the core material to the other surface.

(3)
The fiber composite according to (1) or (2), wherein the cross section includes a structure in which a plurality of the bubbles (C) are surrounded by the resin portion (A).

(4)
The fiber composite according to any one of (1) to (3), wherein the foamed resin is a polyamide-based resin or a polyphenylene ether-based resin.

  ADVANTAGE OF THE INVENTION According to this invention, the fiber composite_body | complex which can obtain the rigidity in the environment of high temperature (for example, 100 degreeC) and the aesthetic appearance can be provided.

FIG. 1 is a schematic view showing a cross-sectional view of an example of the fiber composite of the present embodiment.

  Hereinafter, a mode for carrying out the present invention (hereinafter also referred to as “the present embodiment”) will be described in detail. The following embodiments are examples for explaining the present invention, and the present invention is not limited to the following embodiments, and various modifications can be made within the scope of the gist of the present invention.

[Fiber composite]
The fiber composite of the present embodiment is a fiber composite including a core material including a foamed resin, and a skin material including a fiber and a resin is laminated on at least a part of the surface of the core material. In the cross section in the thickness direction, the core material includes a resin portion (A) having a width of 8 μm or more and bubbles (C) having an average major axis of 5 to 800 μm.

  The fiber composite of this embodiment is preferably a composite in which a skin material containing fibers and a resin is disposed on at least a part of at least one surface of a core material containing a foamed resin. The skin material may be provided on both surfaces of the core material, or may be provided on one surface. The skin material may be provided on a part of the surface of the core material or may be provided on the entire surface.

  That is, in the fiber composite according to the embodiment, the portion on the surface of the core material where the skin material is disposed may be appropriately determined according to the shape of the core material. For example, in the case of a sheet (see Examples described later) May be all or part of one or both sides, in the case of a lump, it may be all or part of the surface that can be seen from a specific direction in a stationary state, and in the case of a line, it may extend from one end. The surface may be all or part of the predetermined length.

The cross section of the fiber composite of this embodiment is demonstrated using FIG.
FIG. 1 is a cross section in the thickness direction of the fiber composite of the present embodiment. The fiber composite 1 is a fiber composite 1 in which a skin material 3 is laminated on the entire surface of both surfaces of a core material 2. The core material 2 includes a substantially solid resin portion (A) 4 having a width of 8 μm or more and bubbles (C) 6 having an average major axis of 5 to 800 μm. By having a wide resin portion (A), it is excellent in rigidity, appearance and surface cosmetics under a high temperature environment.
In the example of FIG. 1, the bubbles (C) 6 are surrounded by a thin resin portion (B) and / or a thick resin portion (A). That is, the boundary between adjacent bubbles consists of a resin part (A) and / or a resin part (B). In particular, since a plurality of bubbles surrounded by the resin portion (B) are included in the region surrounded by the resin portion (A), the rigidity at high temperature is further improved.
The resin portion (A) 4 is continuous in the thickness direction from one surface (for example, the upper surface in FIG. 1) to the other surface (the lower surface in FIG. 1) of the core material on which the skin material 3 is laminated. Connected. The connection method may be straight or may be connected in a mesh pattern as shown in FIG. Further, most of the resin portion (A) 4 is closed, and the closed resin portion (A) 4 includes a resin portion (B) 5 and air bubbles 6.

(Core material)
The said core material in the fiber composite of this embodiment contains foamed resin. The core material may contain a member other than the foamed resin depending on the purpose and application. However, from the viewpoint of easily obtaining the characteristics of the foamed resin, the resin contained in the core material is preferably only the foamed resin, and the core material is more preferably composed only of the foamed resin. Moreover, it is preferable that a core material is a foam containing foamed resin, and it is more preferable that it is a foam which consists only of foamed resin.

-Foam resin-
The foamed resin is preferably a resin having high heat resistance, more preferably a foamed resin mainly composed of a polyester-based resin, a polyamide-based resin, a polyphenylene ether-based resin, a (meth) acrylic resin, and the like, and particularly preferably a polyamide Resin, polyphenylene ether resin.
In addition, a foamed resin may be used independently or 2 or more types may be used together.
Here, “main component” means containing 50% by mass or more, or 60% by mass or more, or 100% by mass with respect to the total amount (100% by mass) of the foamed resin.

  A laminated fiber composite can be formed by superposing a skin material, which will be described later, on the core material, and increasing the temperature and pressure. For this reason, the higher the modulus of elasticity of the core material, the better the appearance of the fiber composite such as the thickness when it is made into a fiber composite. From this point, as the foamed resin, a polyamide resin or a polyphenylene ether resin is used. Is preferred.

As the polyester resin, a high molecular weight linear polyester obtained as a result of a condensation reaction of a dicarboxylic acid and a dihydric alcohol is preferable. Of these, aromatic polyester resins are preferred.
In addition, a polyester-type resin may be used independently or 2 or more types may be used together.

The aromatic polyester resin is preferably a polyester containing an aromatic dicarboxylic acid component and a diol component, such as polyethylene terephthalate, polypropylene terephthalate, polybutylene terephthalate, polycyclohexanedimethylene terephthalate, polyethylene naphthalate, polybutylene naphthalate, etc. Among them, polyethylene terephthalate is preferable.
In addition to the aromatic dicarboxylic acid component and the diol component, the aromatic polyester resin includes, for example, a tricarboxylic acid such as trimellitic acid, a tetracarboxylic acid such as pyromellitic acid, a trivalent or higher polyvalent carboxylic acid, and the like. Trihydric or higher polyhydric alcohols such as anhydrides, triols such as glycerin, and tetraols such as pentaerythritol may be contained as a constituent component.

  When polyethylene terephthalate or the like is used as the polyester resin, it may be crosslinked with a crosslinking agent. Known crosslinking agents are used, and examples thereof include acid dianhydrides such as pyromellitic anhydride, polyfunctional epoxy compounds, oxazoline compounds, and oxazine compounds. In addition, a crosslinking agent may be used independently or 2 or more types may be used together.

Examples of the polyamide-based resin include polyamide, polyamide copolymer, and a mixture thereof.
In addition, a polyamide-type resin may be used individually by 1 type, and may be used in combination of 2 or more type.

  Examples of the polyamide include nylon 66, nylon 610, nylon 612, nylon 46, nylon 1212 and the like obtained by polycondensation of diamine and dicarboxylic acid; nylon 6, nylon 12 and the like obtained by ring-opening polymerization of lactam. And the like.

  Examples of the polyamide copolymer include nylon 6/66, nylon 66/6, nylon 66/610, nylon 66/612, nylon 66 / 6T (T represents a terephthalic acid component), nylon 66 / 6I ( I represents an isophthalic acid component), nylon 6T / 6I, and the like. Among these, aliphatic polyamide is preferable, and nylon 6, nylon 66, nylon 6/66, nylon 66/6, and the like are more preferable.

Examples of the polyamide-based resin mixture include a mixture of nylon 66 and nylon 6, a mixture of nylon 66 and nylon 612, a mixture of nylon 66 and nylon 610, a mixture of nylon 66 and nylon 6I, and nylon 66 The mixture with nylon 6T, the mixture of nylon 6 and nylon 6I / 6T, etc. are mentioned. Among them, from the viewpoint of increasing the crystallinity of the foamed resin and ensuring sufficient heat resistance and surface cosmetic properties of the composite, the polyamide resin in the case of a mixture preferably contains more than 50% by weight of aliphatic polyamide. , 60% by mass or more is more preferable.
In addition, using a compound or a polymer having a substituent that reacts with the amino group or carboxyl group of the polyamide-based resin (hereinafter also referred to as a reactive substituent), the substituent in the molecule of the polyamide-based resin. The degree of cross-linking of the polyamide-based resin may be increased by forming a cross-linked structure via.

Examples of the reactive substituent include functional groups such as a glycidyl group, a carboxyl group, a carboxylic acid metal salt, an ester group, a hydroxyl group, an amino group, and a carbodiimide group, and in particular, from the viewpoint of reaction speed. , A glycidyl group and a carbodiimide group are preferred.
The reactive substituents may be used singly or in combination of two or more. Moreover, the compound, polymer, etc. which have a reactive substituent may have multiple types of functional groups in 1 molecule.
The amount of reactive substituents introduced into the polyamide-based resin is preferably such that gelation or the like does not occur in the resin due to crosslinking.

The highly reactive functional group (amino group and carboxyl group) at the terminal of the polyamide resin is changed to a low reactive functional group by adding a terminal blocking agent in the synthesis of the polyamide resin (polyamide resin). Can be blocked).
In this case, the timing for adding the end-capping agent may be at the time of raw material charging, at the start of polymerization, at the end of polymerization, or at the end of polymerization.

The end-capping agent is not particularly limited as long as it is a monofunctional compound capable of reacting with an amino group or a carboxyl group of a polyamide-based resin, for example, monocarboxylic acid, monoamine, acid anhydride Products, monoisocyanates, monoacid halides, monoesters, monoalcohols and the like. A terminal blocker may be used individually by 1 type, and may be used in combination of 2 or more type.
In particular, when used in a high temperature environment, a heat stabilizer may be used together with the above foamed resin. In particular, as a heat stabilizer, long-term heat aging is effectively prevented under a high temperature environment of 120 ° C. or higher. From the viewpoint, a copper compound is preferable, and a combination of this copper compound and an alkali metal halide compound is also preferable. Here, alkali metal halide compounds include lithium chloride, lithium bromide, lithium iodide, sodium fluoride, sodium chloride, sodium bromide, sodium iodide, potassium fluoride, potassium chloride, potassium bromide, and iodide. Potassium etc. are mentioned. These may be used alone or in combination of two or more.

［式中、Ｒ₁、Ｒ₂、Ｒ₃、及びＲ₄は、それぞれ独立して、水素原子；ハロゲン原子；アルキル基；アルコキシ基；フェニル基；ハロゲン原子と一般式（１）中のベンゼン環との間に少なくとも２個の炭素原子を有するハロアルキル基又はハロアルコキシ基で第３α−炭素を含まない基；からなる群から選択される一価の基である。］ The polyphenylene ether (PPE) resin refers to a polymer containing a repeating unit represented by the following general formula (1). For example, a homopolymer composed of a repeating unit represented by the following general formula (1), Examples thereof include a copolymer containing a repeating unit represented by the general formula (1).

[Wherein R ₁ , R ₂ , R ₃ and R ₄ are each independently a hydrogen atom; a halogen atom; an alkyl group; an alkoxy group; a phenyl group; a halogen atom and a benzene ring in the general formula (1) A monovalent group selected from the group consisting of: a haloalkyl group having at least 2 carbon atoms or a haloalkoxy group that does not contain a third α-carbon. ]

The polyphenylene ether-based resin is not particularly limited. For example, poly (2,6-dimethyl-1,4-phenylene) ether, poly (2,6-diethyl-1,4-phenylene) ether, poly (2- Methyl-6-ethyl-1,4-phenylene) ether, poly (2-methyl-6-propyl-1,4-phenylene) ether, poly (2,6-dipropyl-1,4-phenylene) ether, poly ( 2-ethyl-6-propyl-1,4-phenylene) ether, poly (2,6-dibutyl-1,4-phenylene) ether, poly (2,6-dilauryl-1,4-phenylene) ether, poly ( 2,6-diphenyl-1,4-diphenylene) ether, poly (2,6-dimethoxy-1,4-phenylene) ether, poly (2,6-diethoxy-1) 4-phenylene) ether, poly (2-methoxy-6-ethoxy-1,4-phenylene) ether, poly (2-ethyl-6-stearyloxy-1,4-phenylene) ether, poly (2,6-dichloro) -1,4-phenylene) ether, poly (2-methyl-6-phenyl-1,4-phenylene) ether, poly (2,6-dibenzyl-1,4-phenylene) ether, poly (2-ethoxy-1) , 4-phenylene) ether, poly (2-chloro-1,4-phenylene) ether, poly (2,6-dibromo-1,4-phenylene) ether, and the like. Among them, in particular, in the general formula (1), R ₁ and R ₂ are alkyl groups having 1 to 4 carbon atoms, and R ₃ and R ₄ are hydrogen atoms or alkyl groups having 1 to 4 carbon atoms. The polymer containing is preferable.
The polyphenylene ether resins may be used singly or in combination of two or more.

  The polyphenylene ether-based resin may be used in combination with other resins, and is preferably 40 to 80% by mass, more preferably 40 to 70% by mass with respect to 100% by mass of the resin component of the foamed resin. %. When the PPE content is 40% by mass or more, excellent heat resistance can be obtained, and when the PPE content is 80% by mass or less, excellent workability can be obtained.

Examples of other resins used together with the polyphenylene ether resin include thermoplastic resins and the like, for example, polyolefin resins such as polyethylene, polypropylene, EVA (ethylene-vinyl acetate copolymer); polyvinyl alcohol; polyvinyl chloride; Polyvinylidene chloride; ABS (acrylonitrile-butadiene-styrene) resin; AS (acrylonitrile-styrene) resin; polystyrene resin; methacrylic resin; polyamide resin; polycarbonate resin; polyimide resin; Acrylic resin; Cellulosic resin; Styrene, polyvinyl chloride, polyurethane, polyester, polyamide, 1,2-polybutadiene, fluoroelastomer, etc .; polyamide , Polyacetal, polyester, fluorine-based thermoplastic engineering plastics; and the like. In addition, a modified and crosslinked resin may be used as long as the object of the present invention is not impaired. Among these, polystyrene resins are preferable from the viewpoint of compatibility.
These other resins may be used alone or in combination of two or more.

  Examples of the polystyrene resin in other resins used together with the polyphenylene ether resin include styrene or a homopolymer of a styrene derivative, a copolymer having styrene and / or a styrene derivative as a main component, and the like. Here, “main component” means that the content of structural units derived from styrene and / or styrene derivatives is 60% by mass or more with respect to the total amount of the copolymer (100% by mass).

  The styrene derivative is not particularly limited. For example, o-methylstyrene, m-methylstyrene, p-methylstyrene, t-butylstyrene, α-methylstyrene, β-methylstyrene, diphenylethylene, chlorostyrene, bromo Examples include styrene.

  Examples of homopolymers of styrene or styrene derivatives include polystyrene, poly α-methylstyrene, polychlorostyrene, and the like.

  Examples of the copolymer having styrene and / or styrene derivative as a main component include, for example, styrene-α-olefin copolymer; styrene-butadiene copolymer; styrene-acrylonitrile copolymer; styrene-maleic acid copolymer; Styrene-maleic anhydride copolymer; styrene-maleimide copolymer; styrene-N-phenylmaleimide copolymer; styrene-N-alkylmaleimide copolymer; styrene-N-alkyl-substituted phenylmaleimide copolymer; styrene- Acrylic acid copolymer; Styrene-methacrylic acid copolymer; Styrene-methyl acrylate copolymer; Styrene-methyl methacrylate copolymer; Styrene-n-alkyl acrylate copolymer; Styrene-n-alkyl methacrylate copolymer; Ethyl vinyl benzene-divinyl base Zen copolymer; terpolymer such as ABS, butadiene-acrylonitrile-α-methylbenzene copolymer; styrene graft polyethylene, styrene graft ethylene-vinyl acetate copolymer, (styrene-acrylic acid) graft polyethylene, styrene A graft copolymer such as graft polyamide; and the like. These may be used alone or in combination of two or more. Furthermore, a rubber component such as butadiene may be added to the polystyrene resin as necessary. The content of the rubber component is preferably 1.0 to 20% by mass, for example, 6% by mass with respect to 100% by mass of the polystyrene-based resin.

  Other polycarbonate resins used with the above polyphenylene ether resins include those obtained by reacting a dihydroxy compound and a carbonate precursor by an interfacial polycondensation method or a melt transesterification method. Examples thereof include those obtained by polymerization by a transesterification method, and those obtained by polymerization by a ring-opening polymerization method of a cyclic carbonate compound. The dihydroxy component used here may be one used as a dihydroxy component of an aromatic polycarbonate, and may be a bisphenol or an aliphatic diol.

  Examples of bisphenols include 4,4′-dihydroxybiphenyl, bis (4-hydroxyphenyl) methane, 1,1-bis (4-hydroxyphenyl) ethane, and 1,1-bis (4-hydroxyphenyl) -1- Phenylethane, 2,2-bis (4-hydroxyphenyl) propane, 2,2-bis (4-hydroxy-3-methylphenyl) propane, 1,1-bis (4-hydroxyphenyl) -3,3,5 -Trimethylcyclohexane, 2,2-bis (4-hydroxy-3,3'-biphenyl) propane, 2,2-bis (4-hydroxy-3-isopropylphenyl) propane, 2,2-bis (3-t- Butyl-4-hydroxyphenyl) propane, 2,2-bis (4-hydroxyphenyl) butane, 2,2-bis (4-hydroxyphenyl) ) Octane, 2,2-bis (3-bromo-4-hydroxyphenyl) propane, 2,2-bis (3,5-dimethyl-4-hydroxyphenyl) propane, 2,2-bis (3-cyclohexyl-) 4-hydroxyphenyl) propane, 1,1-bis (3-cyclohexyl-4-hydroxyphenyl) cyclohexane, bis (4-hydroxyphenyl) diphenylmethane, 9,9-bis (4-hydroxyphenyl) fluorene, 9,9- Bis (4-hydroxy-3-methylphenyl) fluorene, 1,1-bis (4-hydroxyphenyl) cyclohexane, 1,1-bis (4-hydroxyphenyl) cyclopentane, 4,4′-dihydroxydiphenyl ether, 4, 4'-dihydroxy-3,3'-dimethyldiphenyl ether, 4,4'- Sulfonyldiphenol, 4,4′-dihydroxydiphenyl sulfoxide, 4,4′-dihydroxydiphenyl sulfide, 2,2′-dimethyl-4,4′-sulfonyldiphenol, 4,4′-dihydroxy-3,3 ′ -Dimethyldiphenyl sulfoxide, 4,4'-dihydroxy-3,3'-dimethyldiphenyl sulfide, 2,2'-diphenyl-4,4'-sulfonyldiphenol, 4,4'-dihydroxy-3,3'-diphenyl Diphenyl sulfoxide, 4,4′-dihydroxy-3,3′-diphenyldiphenyl sulfide, 1,3-bis {2- (4-hydroxyphenyl) propyl} benzene, 1,4-bis {2- (4-hydroxyphenyl) ) Propyl} benzene, 1,4-bis (4-hydroxyphenyl) cyclohexane 1,3-bis (4-hydroxyphenyl) cyclohexane, 4,8-bis (4-hydroxyphenyl) tricyclo [5.2.1.0 (2,6)] decane, 4,4 ′-(1, 3-adamantanediyl) diphenol, 1,3-bis (4-hydroxyphenyl) -5,7-dimethyladamantane, and the like.

  Examples of the aliphatic diols include 2,2-bis- (4-hydroxycyclohexyl) -propane, 1,14-tetradecanediol, octaethylene glycol, 1,16-hexadecanediol, 4,4′-bis (2- Hydroxyethoxy) biphenyl, bis {(2-hydroxyethoxy) phenyl} methane, 1,1-bis {(2-hydroxyethoxy) phenyl} ethane, 1,1-bis {(2-hydroxyethoxy) phenyl} -1- Phenylethane, 2,2-bis {(2-hydroxyethoxy) phenyl} propane, 2,2-bis {(2-hydroxyethoxy) -3-methylphenyl} propane, 1,1-bis {(2-hydroxyethoxy) ) Phenyl} -3,3,5-trimethylcyclohexane, 2,2-bis {4- (2-hydroxy) Ethoxy) -3,3′-biphenyl} propane, 2,2-bis {(2-hydroxyethoxy) -3-isopropylphenyl} propane, 2,2-bis {3-tert-butyl-4- (2-hydroxy) Ethoxy) phenyl} propane, 2,2-bis {(2-hydroxyethoxy) phenyl} butane, 2,2-bis {(2-hydroxyethoxy) phenyl} -4-methylpentane, 2,2-bis {(2 -Hydroxyethoxy) phenyl} octane, 1,1-bis {(2-hydroxyethoxy) phenyl} decane, 2,2-bis {3-bromo-4- (2-hydroxyethoxy) phenyl} propane, 2,2- Bis {3,5-dimethyl-4- (2-hydroxyethoxy) phenyl} propane, 2,2-bis {3-cyclohexyl-4- (2-hydroxyethyl) Xyl) phenyl} propane, 1,1-bis {3-cyclohexyl-4- (2-hydroxyethoxy) phenyl} cyclohexane, bis {(2-hydroxyethoxy) phenyl} diphenylmethane, 9,9-bis {(2-hydroxy) Ethoxy) phenyl} fluorene, 9,9-bis {4- (2-hydroxyethoxy) -3-methylphenyl} fluorene, 1,1-bis {(2-hydroxyethoxy) phenyl} cyclohexane, 1,1-bis { (2-hydroxyethoxy) phenyl} cyclopentane, 4,4′-bis (2-hydroxyethoxy) diphenyl ether, 4,4′-bis (2-hydroxyethoxy) -3,3′-dimethyldiphenyl ether, 1,3- Bis [2-{(2-hydroxyethoxy) phenyl} propyl] benzene, 1 , 4-bis [2-{(2-hydroxyethoxy) phenyl} propyl] benzene, 1,4-bis {(2-hydroxyethoxy) phenyl} cyclohexane, 1,3-bis {(2-hydroxyethoxy) phenyl} Cyclohexane, 4,8-bis {(2-hydroxyethoxy) phenyl} tricyclo [5.2.1.0 (2,6)] decane, 1,3-bis {(2-hydroxyethoxy) phenyl} -5, 7-dimethyladamantane, 3,9-bis (2-hydroxy-1,1-dimethylethyl) -2,4,8,10-tetraoxaspiro (5,5) undecane, 1,4: 3,6-dianhydro -D-sorbitol (isosorbide), 1,4: 3,6-dianhydro-D-mannitol (isomannide), 1,4: 3,6-dianhydro-L-idito Le (isoidide) and the like. Among these, aromatic bisphenols are preferable, among which 1,1-bis (4-hydroxyphenyl) -1-phenylethane, 2,2-bis (4-hydroxyphenyl) propane, and 2,2-bis (4 -Hydroxy-3-methylphenyl) propane, 1,1-bis (4-hydroxyphenyl) cyclohexane, 1,1-bis (4-hydroxyphenyl) -3,3,5-trimethylcyclohexane, 4,4'-sulfonyl Diphenol, 2,2′-dimethyl-4,4′-sulfonyldiphenol, 9,9-bis (4-hydroxy-3-methylphenyl) fluorene, 1,3-bis {2- (4-hydroxyphenyl) Propyl} benzene and 1,4-bis {2- (4-hydroxyphenyl) propyl} benzene are preferred. In particular 2,2-bis (4-hydroxyphenyl) propane, 1,1-bis (4-hydroxyphenyl) cyclohexane, 4,4'-sulfonyldiphenol and 9,9-bis (4-hydroxy-3-methyl) Phenyl) fluorene is preferred. Among these, 2,2-bis (4-hydroxyphenyl) propane having the excellent strength and good durability is most preferable. Moreover, you may use these individually or in combination of 2 or more types. Further, the polycarbonate resin may be a branched polycarbonate resin by using a branching agent in combination with the dihydroxy compound.

  Examples of the trifunctional or higher polyfunctional aromatic compound as a branching agent used in such a branched polycarbonate resin include phloroglucin, phloroglucid, 4,6-dimethyl-2,4,6-tris (4-hydroxydiphenyl). Heptene-2,2,4,6-trimethyl-2,4,6-tris (4-hydroxyphenyl) heptane, 1,3,5-tris (4-hydroxyphenyl) benzene, 1,1,1-tris ( 4-hydroxyphenyl) ethane, 1,1,1-tris (3,5-dimethyl-4-hydroxyphenyl) ethane, 2,6-bis (2-hydroxy-5-methylbenzyl) -4-methylphenol, 4 -Trisphenol such as {4- [1,1-bis (4-hydroxyphenyl) ethyl] benzene} -α, α-dimethylbenzylphenol It is done. Tetra (4-hydroxyphenyl) methane, bis (2,4-dihydroxyphenyl) ketone, 1,4-bis (4,4-dihydroxytriphenylmethyl) benzene, trimellitic acid, pyromellitic acid, benzophenonetetracarboxylic Examples thereof include acids and acid chlorides thereof. Of these, 1,1,1-tris (4-hydroxyphenyl) ethane and 1,1,1-tris (3,5-dimethyl-4-hydroxyphenyl) ethane are preferable, and 1,1,1-tris (4- Hydroxyphenyl) ethane is preferred. Further, the end of the polycarbonate resin may be sealed with phenol or the like.

The (meth) acrylic resin is produced by polymerizing a (meth) acrylic monomer. In addition, (meth) acryl means either one or both of acryl and methacryl.
The said (meth) acrylic-type resin may be used individually by 1 type, or may be used in combination of 2 or more type.

The (meth) acrylic monomer is not particularly limited, and (meth) acrylic acid, methyl (meth) acrylate, ethyl (meth) acrylate, butyl (meth) acrylate, lauryl (meth) acrylate, ( Examples include 2-ethylhexyl (meth) acrylate, cyclohexyl (meth) acrylate, benzyl (meth) acrylate, and (meth) acrylamide.
Moreover, the said (meth) acrylic-type resin may contain the monomer component copolymerizable with this other than the said (meth) acrylic-type monomer. Examples of such monomers include maleic acid, maleic anhydride, fumaric acid, itaconic acid, itaconic anhydride, crotonic acid, maleic amide, maleic imide and the like.
In addition, heat, and if necessary, salt, alkali, acid, dehydration reaction, deethanol reaction, amine exchange reaction, glutaric anhydride, (meth) acrylimide ring, lactone ring on the main chain By introducing it, heat resistance may be imparted. Particularly preferred are methacrylimide resins, copolymer resins of maleic anhydride and (meth) acryl, and styrene.

  The foamed resin may optionally further contain other components such as additives, a small amount of gas, and the like. Other components that may be included in the foamed resin include stabilizers, impact modifiers, flame retardants, lubricants, pigments, dyes, weathering modifiers, antistatic agents, impact modifiers, crystal nucleating agents, glass Examples include beads, inorganic fillers, crosslinking agents, nucleating agents such as talc, other thermoplastic resins, and the like, and they may be added as long as the object of the present invention is not impaired. The content of the other components in the foamed resin may be 30 parts by mass or less, preferably 25 parts by mass or less, and more preferably 20 parts by mass or less with respect to 100 parts by mass of the foamed resin.

In particular, the stabilizer is not particularly limited, and examples thereof include organic antioxidants such as hindered phenol antioxidants, sulfur antioxidants, phosphorus antioxidants, phosphite compounds, and thioether compounds. And light stabilizers such as hindered amines, benzophenones, and imidazoles, ultraviolet absorbers, metal deactivators, and the like.
These may be used alone or in combination of two or more.

The trace gas that may be contained in the foamed resin is contained in the process of producing the foamed resin (described later). The gas is not particularly limited, and examples thereof include air, carbon dioxide gas, various gases used as a foaming agent, aliphatic hydrocarbon gas, alcohol, and the like. Specific examples of the aliphatic hydrocarbon gas include butane and pentane. Examples of the alcohol include methanol, ethanol, butanol, pentanol and the like.
The content of the trace gas is preferably less than 0.1% by mass, more preferably 0.07% by mass or less, and particularly preferably not contained in 100% by mass of the core material. Less gas is preferred as the appearance because it can prevent the foamed resin from expanding under the influence of gas in an environment of 100 ° C. when it is made into a fiber composite.

  Further, the foamed resin may contain other thermoplastic resins. Other thermoplastic resins include, for example, polyolefin resins such as polyethylene, polypropylene, EVA (ethylene-vinyl acetate copolymer); polyvinyl alcohol; polyvinyl chloride; polyvinylidene chloride; polycarbonate resins; polyimide resins; Cellulosic resin; Cellulosic resin; Thermoplastic elastomers such as polyvinyl chloride, polyurethane, polyester, 1,2-polybutadiene, and fluoro rubber; Polyacetal, polyester, and fluorine thermoplastic engineering plastics; Can be mentioned. In addition, a modified and crosslinked resin may be used as long as the object of the present invention is not impaired. These may be used alone or in combination of two or more.

-Resin part (A)-
The core material preferably includes a resin portion (A) and bubbles (C), and further includes a resin portion (B). The core material may have a structure other than the resin part (A), the resin part (B), and the bubbles (C).

The resin portion (A) contained in the core material of the present embodiment is a substantially solid resin portion having a width of 8 μm or more in a cross section obtained by cutting the fiber composite in the thickness direction. It is preferable. The width of the resin portion (A) is preferably 8 μm or more because the fiber composite has high rigidity in an environment at high temperatures. More preferably, it is 9 micrometers or more, More preferably, it is 12 micrometers or more.
Here, the width of the resin portion (the width of the resin portion at an arbitrary point a on the bubble periphery) refers to the distance between the bubble periphery of adjacent bubbles. Specifically, in the cross section, on the bubble periphery. The length of the line segment connecting the two points where the length of the line segment connecting the point a and the point b on the outer periphery of the bubble adjacent to the bubble is the minimum distance. However, it is assumed that the line segment passes only through the resin portion and does not pass the bubbles (C). The width of the resin portion at point a on the outer periphery of the bubble is preferably 8 μm or more. The width of the resin portion at point a and the width of the resin portion at point b are both preferably 8 μm or more.

  The resin constituting the resin portion (A) may be the same as or different from the foamed resin. The width of the resin portion (A) and the major axis of the bubbles are measured by the methods described in the examples below.

  The resin part (A) has a point where the width of the resin part is 8 μm or more, preferably 1 mm or more, more preferably 5 mm or more, from the viewpoint of further improving rigidity in a high temperature environment. It is more preferable that it continues more than the thickness of a body, and it is especially preferable to continue 1.5 times or more of the thickness of a foam. Among these, the point where the width of the resin portion is 8 μm or more preferably continues for 1 mm or more continuously in the thickness direction, and more preferably continues for 5 mm or more. Moreover, it is preferable that it continues 50% or more with respect to 100% of the thickness of a foam continuously in the thickness direction, and it is more preferable that it continues 100%.

The average width of the resin portion (A) contained in the core material is preferably 8 to 40 μm from the viewpoint of further excellent rigidity in a high temperature environment.
In addition, the average width | variety of a resin part (A) can be measured by the method as described in the below-mentioned Example.

In the cross section, the resin part (A) preferably has at least a part of the resin part (A) continuously connected from one surface of the core material on which the skin material is laminated to the other surface. Since the wide resin portions (A) are continuously connected in this way, the structure as the structural material of the core material can be realized by the thick resin portions (A), and the thick resin portions (A) even at high temperatures. ) Plays a role as a support material, which is preferable because the bending strength of the core material of the fiber composite can be maintained.
In the cross section, the resin portion (A) may be continuously connected linearly in the thickness direction, or may be continuously connected in a curved shape. Among these, from the viewpoint of further improving rigidity in a high temperature environment, it is preferable to have a plurality of resin portions (A) continuously connected in the thickness direction, and a resin continuously connected in the thickness direction linearly and / or curvedly. It is more preferable to have a network structure (see FIG. 1) having a plurality of portions (A) and connecting these resin portions in the width direction (direction perpendicular to the thickness direction in the cross section). The mesh structure may be in a part of the core material having the cross section or in the whole core material.

From the viewpoint of further excellent rigidity under a high temperature environment, in the cross section, the interface between the core material and the skin material preferably includes the resin portion (A), and the entire surface may be the resin portion (A). However, a part may be a resin part (A) (refer FIG. 1).
In the cross section, the interface between the core material and air (both ends in the width direction of the cross section) may include the resin portion (A), or the entire surface may be the resin portion (A). However, a part may be a resin part (A) (refer FIG. 1).

-Resin part (B)-
The resin part (B) is a resin part having a width of 6 μm or less. The resin part (B) represents a partition wall between bubbles contained in the core material, and corresponds to a wall surface of the bubble. When the width of the resin part (B) is 6 μm or less, it is preferable that the distance between the bubbles is short, that the bubbles are densely present in the core material, and that the weight is light and the rigidity at high temperature is uniform. More preferably, it is 5 micrometers or less, More preferably, it is 4 micrometers or less. The measuring method of the width | variety of the resin part (B) is measured by the method as described in the below-mentioned Example.

The average width of the resin part (B) contained in the core material is preferably 0.6 to 6 μm from the viewpoint of further excellent rigidity under a high temperature environment.
In addition, the average width | variety of a resin part (B) can be measured by the method as described in the below-mentioned Example.
In addition, the average width of the resin part (A) and the resin part (B) in this specification shall mean the value calculated | required from the arbitrary 30 resin parts in which each width satisfy | fills a specific range.

-Bubble (C)-
The average major axis of the bubbles (C) is preferably 5 to 800 μm, more preferably 10 to 700 μm. If the average major axis of the bubbles is in this range, impact energy can be sufficiently absorbed, particularly in a high temperature environment of 100 ° C., which is preferable.
In the present specification, the average major axis of the bubbles refers to a value measured by the method described in Examples described later. The average major axis in the present specification refers to a value obtained from any 30 bubbles whose average major axis satisfies a specific range.

  The cross section preferably includes a structure in which a plurality of bubbles (C) are surrounded by the resin portion (A). It is preferable that the resin part (B) and the said bubble (C) in the core material of this embodiment are surrounded by the resin part (A). A core material that includes a thin resin portion (B) and bubbles (C) and does not include a resin portion (A) generally tends to break at high temperatures and has low strength. It is preferable to be surrounded by the thick resin portion (A) because the resin portion (A) can withstand stress when stress is applied to the fiber composite at high temperature. Furthermore, it is more preferable that the resin part (B) and the bubbles (C) are surrounded by the resin part (A) finely meshed in the core material. As a unit surrounded by the resin part (A), the major axis is preferably 100 μm to 3 mm, more preferably 300 μm to 3 mm.

The resin constituting the resin part (A) and the resin part (B) in the core material may be the same or different.
As a manufacturing method of the fiber composite of this embodiment, the foamed resin which consists of a resin part (B) and a bubble (C) may be stuffed between the mesh-shaped resin parts (A) produced previously, or a resin part ( The resin part (A) may be formed by bonding a foamed resin composed of B) and bubbles (C) with a resin that is a raw material of the resin part (A), or the resin part (B) and the bubbles (C). The resin portion (A) from which bubbles are removed by welding a foamed resin made of may be configured.

The apparent density of the core material is preferably from 10~700kg / m ^3, more preferably 20~600kg / m ^3. When the apparent density is moderate, especially in a high temperature environment such as 100 ° C., when a strong impact is applied to the fiber composite, the stress concentration part is not easily generated due to the buckling of the bubbles, and the skin material is easily formed. Less likely to be deformed and destroyed, which is preferable. Moreover, it is preferable for the purpose of weight reduction.
In addition, in this specification, an apparent density means the value measured by the method as described in the below-mentioned Example calculated | required from the volume and weight which cut out only the core material from the fiber reinforced composite and measured.

(Skin material)
It is preferable that the skin material containing the fiber and resin used for the fiber composite of this embodiment is made by impregnating a reinforcing synthetic resin into a reinforcing fiber.

  The skin material does not need to be laminated and integrated on both surfaces of the core material, and the skin material only needs to be laminated and integrated on at least one surface of the core material. The lamination of the skin material may be determined according to the use of the fiber composite. Among these, in consideration of the impact resistance of the fiber composite, it is preferable that the skin material is laminated and integrated on each of the upper and lower surfaces in the thickness direction of the core material. As shown in FIG. 1, such a fiber composite 1 has a core material 2 made of foamed resin, and a skin material 3 that is laminated and integrated on both surfaces of the core material 2.

  The fibers constituting the skin material are preferably reinforcing fibers. Reinforcing fibers include glass fibers, carbon fibers, silicon carbide fibers, alumina fibers, tyrano fibers, basalt fibers, ceramic fibers, etc .; metal fibers such as stainless steel fibers and steel fibers; aramid fibers, polyethylene fibers, polyparaphenylene Organic fibers such as benzoxador (PBO) fibers; boron fibers and the like. The reinforcing fibers may be used alone or in combination of two or more. Among these, carbon fiber, glass fiber, and aramid fiber are preferable, and carbon fiber is more preferable. These reinforcing fibers have excellent mechanical strength despite being lightweight.

  The reinforcing fiber is preferably used as a reinforcing fiber substrate processed into a desired shape. Examples of the reinforcing fiber base material include woven fabrics, knitted fabrics, non-woven fabrics, and face materials obtained by binding (stitching) fiber bundles (strands) obtained by aligning reinforcing fibers in one direction with yarns. . Examples of the weaving method include plain weave, twill weave and satin weave. Moreover, as a thread | yarn used when binding a fiber bundle, stitch resin yarns, such as synthetic resin yarns, such as a polyamide resin yarn and a polyester resin yarn, and a glass fiber yarn are mentioned.

  As the reinforcing fiber substrate, only one reinforcing fiber substrate may be used, or a plurality of reinforcing fiber substrates may be laminated and used as a laminated reinforcing fiber substrate. As the laminated reinforcing fiber substrate, (1) a plurality of reinforcing fiber substrates of only one kind, a laminated reinforcing fiber substrate obtained by laminating these reinforcing fiber substrates, and (2) a plurality of reinforcing fiber substrates. (3) a plurality of face materials obtained by binding (sewing) fiber bundles (strands) in which reinforcing fibers are aligned in one direction with yarns. A laminated reinforcing fiber base material prepared by stacking these face materials so that the fiber directions of the fiber bundles are different from each other, and integrating the stitched face materials with a thread (stitching). Is mentioned. Examples of the yarn used when integrating the face materials include synthetic resin yarns such as polyamide resin yarns and polyester resin yarns, and stitch yarns such as glass fiber yarns.

  The skin material is preferably formed by impregnating reinforcing fibers into reinforcing fibers. Reinforcing fibers can be bound and integrated by the impregnated reinforcing resin. As the reinforcing resin impregnated into the reinforcing fiber, either a thermoplastic resin or a thermosetting resin can be used, and a thermosetting resin is preferably used. The reinforcing resin may be used alone or in combination of two or more.

  The thermosetting resin is not particularly limited, and examples thereof include thermosetting epoxy resins, unsaturated polyester resins, phenol resins, melamine resins, thermosetting polyurethane resins, silicon resins, maleimide resins, vinyl ester resins, and cyanate esters. Examples thereof include resins, resins obtained by prepolymerizing maleimide resins and cyanate ester resins, and the like, and epoxy resins and vinyl ester resins are preferred because of excellent heat resistance, shock absorption, and chemical resistance. The thermosetting resin may contain additives such as a curing agent and a curing accelerator.

  The thermoplastic resin is not particularly limited, and examples thereof include olefin resins, polyester resins, thermoplastic epoxy resins, amide resins, thermoplastic polyurethane resins, sulfide resins, acrylic resins, and the like, and adhesion to foams. Polyester resin and thermoplastic epoxy resin are preferable because they are excellent in adhesion between reinforcing fibers constituting the fiber property or fiber reinforced plastic layer and have high heat resistance.

  The epoxy resin as the thermoplastic resin is a polymer or copolymer of epoxy compounds having a linear structure, an epoxy compound, and a monomer that can be polymerized with the epoxy compound. Examples thereof include a copolymer having a linear structure. Specifically, for example, bisphenol A type epoxy resin, bisphenol fluorene type epoxy resin, cresol novolac type epoxy resin, phenol novolac type epoxy resin, cyclic aliphatic type epoxy resin, long chain aliphatic type epoxy resin, glycidyl ester type epoxy Examples thereof include resins and glycidylamine type epoxy resins, and bisphenol A type epoxy resins and bisphenol fluorene type epoxy resins are preferred.

Examples of the polyurethane resin as the thermoplastic resin include a polymer having a linear structure obtained by polymerizing diol and diisocyanate.
Examples of the diol include ethylene glycol, diethylene glycol, propylene glycol, dipropylene glycol, 1,3-butanediol, 1,4-butanediol, and the like. Diols may be used alone or in combination of two or more.
Examples of the diisocyanate include aromatic diisocyanate, aliphatic diisocyanate, and alicyclic diisocyanate. Diisocyanate may be used alone or in combination of two or more.

  20-70 mass% is preferable with respect to 100 mass% of skin materials, and, as for content of resin (preferably synthetic resin for reinforcement | strengthening) in a skin material, 30-60 mass% is more preferable. If the content of the resin (preferably, the reinforcing synthetic resin) is too small, the binding property between the fibers and the adhesion between the skin material and the core material become insufficient, and the mechanical strength of the skin material and the fiber composite There is a possibility that the impact resistance cannot be sufficiently improved. Moreover, when there is too much content of resin, the mechanical strength of a skin material will fall and it may be unable to fully improve the impact resistance of a fiber composite. Also, higher heat resistance of the resin is preferable in order to maintain rigidity at high temperature, but if it is too high, high temperature is required for bonding, resulting in a longer molding time and lower productivity. The heat resistance can be represented by the glass transition temperature of the resin, and in the case of a thermosetting resin, it is represented by the glass transition temperature after curing. A preferable glass transition temperature is 70 to 150 ° C, and more preferably 75 to 140 ° C. The glass transition temperature can be measured based on JIS K7121.

  The thickness of the skin material is preferably 0.02 to 2 mm, more preferably 0.05 to 1 mm per layer. A skin material having a thickness within the above range is excellent in mechanical strength despite being lightweight.

Basis weight of the skin material is preferably ^{50~4000g / m 2, 100~1000g / m} 2 is more preferable. A skin material having a basis weight within the above range is excellent in mechanical strength despite being lightweight.

[Production method]
(Manufacturing method of core material)
As a manufacturing method of the core material including the foamed resin of the present embodiment, a known manufacturing method can be used. Specifically, (1) foam molded products (foamed) are prepared by filling resin particles having foamability into a mold, heating with water vapor or the like, foaming the resin particles, and thermally fusing the resin particles together. (2) Synthetic resin is supplied to an extruder, melted and kneaded in the presence of a foaming agent such as a chemical foaming agent or a physical foaming agent, and extruded and foamed from the extruder. (3) A synthetic resin and a chemical foaming agent are supplied to an extruder, melt-kneaded at a temperature lower than the decomposition temperature of the chemical foaming agent, and a foamable resin molded product is produced from the extruder. And a method for producing a foam by foaming the foamable resin molded body. Above all, the in-mold foam molding method has advantages such as easy setting of the product shape and easy to obtain a foam molded product with a high expansion ratio. It is possible to provide the resin part (A) by post-processing in the extrusion foaming method of (2) and (3), but among these, the in-mold foam molding method of (1) is preliminarily resin part ( The precursor of A) is obtained, and it is preferable that the resin part (B) and the bubbles can be obtained by molding once by foaming.

Examples of the resin particles used in the in-mold foam molding method include pre-foamed particles. For example, when producing a polyamide-based resin foam, polyamide-based pre-expanded particles can be used.
In the present specification, the pre-expanded particles refer to resin particles (beads, etc.) having expandability that are not expanded at the final stage.

  The pre-expanded particles can be obtained by causing foaming to occur (impregnated) with a foaming agent contained in the resin that is the raw material of the foamed resin. For example, the method for incorporating (impregnating) the foaming agent into the polyamide-based resin is not particularly limited, and may be a generally used method.

  As a method for impregnating a resin with a foaming agent, a method using an aqueous medium in a suspension system such as water (suspension impregnation method), a method using a thermally decomposable foaming agent such as sodium bicarbonate (foaming agent decomposition method) ), A method in which the gas is brought into a liquid phase state in an atmosphere above the critical pressure and brought into contact with the resin (liquid phase impregnation method); Impregnation method) and the like. A gas phase impregnation method is particularly preferable as a method of incorporating a foaming agent.

  Examples of the foaming agent decomposition method include a method using a thermal decomposition type foaming agent such as azodicarbonamide, dinitrosopentamethylenetetramine, hydrazoyl dicarbonamide, sodium bicarbonate, and the like. In addition, a thermal decomposition type foaming agent may be used independently, or 2 or more types may be used together.

  In the gas phase impregnation method, the solubility of the gas in the resin is higher and the content of the foaming agent is likely to be higher than in the suspension impregnation method performed under high temperature conditions. Therefore, in the gas phase impregnation method, it is easy to achieve a high expansion ratio, and the bubble size in the pre-expanded particles tends to be uniform.

  Moreover, the said foaming agent decomposition | disassembly method is implemented on high temperature conditions similarly to the suspension impregnation method. Further, in this method, not all of the added pyrolytic foaming agent becomes gas, so that the amount of gas generation tends to be relatively small. Therefore, the gas phase impregnation method has an advantage of easily increasing the foaming agent content. Furthermore, in the vapor phase impregnation method, compared to the liquid phase impregnation method, facilities such as a pressure device and a cooling device are likely to be more compact, and the facility cost is likely to be reduced.

  The shape of the resin used in the gas phase impregnation method is not particularly limited, and examples thereof include beads, pellets, spheres, irregularly pulverized products, and the size thereof is prefoamed after foaming. The average diameter is preferably 0.2 to 3 mm from the viewpoint of making the particle size appropriate, improving the ease of handling of the pre-foamed particles, and making the filling during molding more dense.

The conditions for the vapor phase impregnation method are not particularly limited, and for example, from the viewpoint of more efficiently promoting the dissolution of the gas into the resin, the atmospheric pressure may be 0.5 to 6.0 MPa. Preferably, the atmospheric temperature is preferably 5 to 30 ° C.
Here, as a foaming agent used when manufacturing the said pre-expanded particle, the compound etc. which can be used as air or gas are mentioned, without being specifically limited.

Examples of compounds that can be used as gases include inorganic compounds such as carbon dioxide, nitrogen, oxygen, hydrogen, argon, helium, and neon; trichlorofluoromethane (R11), dichlorodifluoromethane (R12), chlorodifluoromethane (R22), tetra Fluorocarbons such as chlorodifluoroethane (R112), dichlorofluoroethane (R141b), chlorodifluoroethane (R142b), difluoroethane (R152a), HFC-245fa, HFC-236ea, HFC-245ca, HFC-225ca; HFO-1234y, HFO-1234ze Hydrofluoroolefins such as (E); saturated hydrocarbons such as propane, n-butane, i-butane, n-pentane, i-pentane, neopentane; dimethyl ether, diethyl ether, Ethers such as tilethyl ether, isopropyl ether, n-butyl ether, diisopropyl ether, furan, furfural, 2-methylfuran, tetrahydrofuran, tetrahydropyran; chlorinated hydrocarbons such as methyl chloride and ethyl chloride; methanol, ethanol, etc. Alcohols; and the like.
These compounds that can be used as air or gas may be used alone or in combination of two or more.

  As the foaming agent, those that have little impact on the environment and that do not have flammability or flame support are preferable, and from the viewpoint of safety during handling, inorganic compounds that are not flammable and flame support are more preferable, From the viewpoint of solubility and ease of handling, carbon dioxide gas (carbon dioxide gas) is particularly preferred.

  A method of causing foaming in a resin containing (impregnated with) a foaming agent (foaming agent-impregnated resin) is not particularly limited. For example, a foaming agent-impregnated resin such as a foaming agent-impregnated polyamide resin is reduced from a high pressure atmosphere to a low pressure. A blowing agent-impregnated resin that is brought into the atmosphere at a stretch by expanding the gas as the blowing agent dissolved in the blowing agent-impregnated resin to cause foaming, or by heating using pressure steam or the like It is possible to use a method of expanding the gas inside to generate foam, and in particular, the advantage of uniforming the size (cell size) of bubbles inside the molded product, which is the product, and controlling the expansion ratio Since the advantage of facilitating the production of a molded article having a low expansion ratio is obtained, the latter method of heating and foaming is preferably used.

  Here, when the pre-expanded particles are expanded to a desired expansion ratio, one-stage expansion may be performed, or multi-stage expansion including secondary expansion, tertiary expansion, or the like may be performed. In addition, when performing multi-stage foaming, it is easy to prepare pre-foamed particles with a high foaming ratio, and the pre-foamed particles used for molding are used for the third foaming from the viewpoint of reducing the amount of resin used per unit volume. It is preferable that the pre-expanded particles are used.

  In particular, in the case of multi-stage foaming, it is preferable to perform a pressure treatment with gas on the pre-foamed particles before foaming in each stage. The gas used for the pressure treatment is not particularly limited as long as it is inert to the resin, but inorganic gases and hydrofluoroolefins having high gas safety and low gas global warming potential are preferred. Examples of the inorganic gas include air, carbon dioxide gas, nitrogen gas, oxygen gas, ammonia gas, hydrogen gas, argon gas, helium gas, and neon gas. Examples of the hydrofluoroolefin include HFO-1234y, HFO-1234ze (E) and the like can be mentioned, and air and carbon dioxide are particularly preferable from the viewpoints of ease of handling and economy. A technique for the pressure treatment is not particularly limited, and examples thereof include a technique of filling pre-expanded particles in a pressurized tank and supplying gas into the tank.

  The foamed resin preferably contains the pre-expanded particles, and can be obtained, for example, by molding the pre-expanded particles. The pre-expanded particles may be used alone or in combination of two or more.

The method of forming the pre-expanded particles is not particularly limited. For example, the pre-expanded particles are filled in the cavities of the molding die and heated to cause foaming, and at the same time, the pre-expanded particles are thermally melted together. After deposition, the product can be solidified by cooling and shaped. Here, the filling method of the pre-expanded particles is not particularly limited. For example, a cracking method in which the pre-expanded particles are filled with the mold slightly opened, or a pre-compressed pre-pressed particle with the mold closed. Examples thereof include a compression method in which expanded particles are filled, and a compression cracking method in which the above-described cracking method is performed after filling pre-expanded particles that have been compressed into a mold.
From the viewpoint of uniforming the size of the bubbles inside the particles (cell size) by applying a certain gas pressure to the bubbles of the pre-expanded particles, before filling the pre-expanded particles into the cavity of the molding die, It is preferable to subject the pre-expanded particles to pressure treatment with a gas. Although it does not specifically limit as gas used for a pressurization process, From a flame retardance, heat resistance, and a viewpoint of dimensional stability, inorganic gas etc. are mentioned. The inorganic gas and the pressure treatment method are the same as in the pressure treatment with the gas applied to the pre-expanded particles in the case of multistage foaming.

  The heat medium used when forming the pre-expanded particles may be a general-purpose heat medium, and is preferably saturated steam or superheated steam from the viewpoint of suppressing oxidative deterioration of the foamed resin, and is uniform with respect to the foamed resin. From the viewpoint of enabling heating, saturated steam is more preferable.

  The method for producing the foamed resin includes, for example, a filling step of filling the pre-expanded particles in the cavity of the mold, and supplying water vapor below the heat-sealing temperature of the pre-foamed particles into the cavity for 5 to 30 seconds. A preheating step of preheating the pre-foamed particles, and supplying water vapor at a temperature equal to or higher than the heat-fusion temperature of the pre-foamed particles into the cavity for 20 to 120 seconds to cause the pre-foamed particles to foam and heat-fuse. And a fusing step for obtaining a foamed resin.

  The foamed resin is preferably obtained by heating pre-foamed particles in two stages in a preheating step and a fusing step.

  According to this method, in the first stage, the pre-expanded particles are preliminarily heated with water vapor below the heat fusion temperature of the pre-expanded particles, thereby making the temperature distribution in the entire aggregate of the pre-expanded particles more uniform. be able to. Then, by the preliminary heating at the first stage, when the pre-expanded particles are heated with the steam higher than the heat fusion temperature in the second stage, the foaming in the pre-expanded particles becomes more uniform. Can be easily formed into a foam.

  Moreover, according to this method, in the obtained foamed resin, the crystallite size of the resin becomes larger, the degree of crystallinity becomes higher, and as a result, a core material excellent in heat resistance can be obtained.

As described above, the temperature at which the pre-expanded particles are heated is preferably in the vicinity of the heat fusion temperature (Tf) of the pre-expanded particles.
In the present specification, the heat fusion temperature refers to a temperature at which the prefoamed particles are heated in saturated steam and the prefoamed particles are fused. The method for measuring the heat fusion temperature is as described below. In addition, in this specification, heat fusion temperature means the value measured by the method as described in the below-mentioned Example.

The first stage heating temperature is desirably lower than Tf (° C), preferably Tf-20 ° C or higher, more preferably Tf-15 ° C or higher, and Tf-2 ° C. It is preferable that it is below, and it is still more preferable that it is below Tf-5 degreeC.
The heating time for the first stage is preferably 2 seconds or more, more preferably 3 seconds or more, preferably 20 seconds or less, and more preferably 15 seconds or less.

The heating temperature in the second stage is higher than Tf (° C.), preferably Tf + 15 ° C. or less, more preferably Tf + 10 ° C. or less, and particularly preferably Tf + 5 ° C. or less.
The heating time for the second stage is desirably 10 seconds or more, more desirably 15 seconds or more, desirably 60 seconds or less, and more desirably 45 seconds or less.

  If the heating temperature and heating time of the first stage and the second stage are within the above ranges, the pre-foamed particles can be sufficiently heat-sealed with each other, and a foam in which crystallization of the resin is further promoted can be obtained. Can be obtained.

The density of the foam before lamination is 20 kg / m ³ or more from the viewpoint of improving the appearance of the foamed resin or fiber composite by making the strength of the foamed resin moderate and making the cell membrane difficult to break. it is preferred, further preferably 50 kg / m ³ or more, from the viewpoint of enhancing the light weight of the fiber composite, it is preferably 800 kg / m ³ or less, still be less than 500 kg / m ³ preferable.
In addition, the density of a foam can be measured by the method as described in the below-mentioned Example.

The closed cell ratio S of the foam before lamination improves the strength of the foamed resin and makes it difficult for water to be taken into the foam that may occur in the open cell portion, thereby making it difficult to reduce the density of the foam. From the viewpoint, it is preferably 80% or more, and more preferably 85% or more.
The closed cell ratio S (%) is calculated by an expression represented by the following expression (3).
S (%) = {(Vx−W / ρ) / (Va−W / ρ)} × 100 (3)
Where Vx is the true volume of the foam (cm ³ ), Va is the apparent volume of the foam (cm ³ ), W is the weight of the foam (g), and ρ is The density (g / cm ³ ) of the base resin of the foam.
The closed cell ratio can be measured by cutting the skin material from the fiber composite. In addition, the closed cell ratio can be measured by the method described in Examples described later.

The foam before lamination preferably has a dimensional change rate at 150 ° C. of 1.5% or less, and 1.0% or less, from the viewpoint of suppressing deterioration of physical properties and heat shrinkage in a high temperature environment. More preferably.
The dimensional change rate is a value measured in accordance with JIS K6767 dimensional stability evaluation / B method.

  Further, the expansion ratio of the foam before lamination is preferably 1.3 to 60 times, more preferably 1.5 to 30 times, and more preferably 5 to 20 times. The foam having an expansion ratio within the above range has an appropriate heat transfer property, so that a desired wide resin portion (A) is formed in the core material in the compression step when the fiber composite is manufactured. It is easy to form. In the present invention, the expansion ratio of the foam is a value measured according to JIS K7222.

The fusion rate of the foam before lamination is very important for the formation of the resin part (A), and the viewpoint of increasing rigidity when stress such as bending strain is applied to the composite, and the foam is cut. From the viewpoint of suppressing missing of the pre-expanded particles from the molded product, it is preferably 60% or more, more preferably 70% or more, and most preferably 80% or more.
The method for measuring the fusion rate is as described in the examples.

(Production method of fiber composite)
As a method for producing the fiber composite of the present embodiment, a known thermoforming method can be used, and examples thereof include a vacuum forming method, a pressure forming method, and a compression forming method. Examples of thermoforming methods that apply vacuum forming method and pressure forming method include straight forming method, drape forming method, plug assist forming method, plug assist reverse draw forming method, air slip forming method, snapback forming method, reverse draw method. Examples thereof include a molding method, a plug assist / air slip molding method, a match mold molding method, and a thermoforming method combining these molding methods.

  Above all, when using foamed resin obtained by heat fusion foam molding using pre-expanded particles as a core material, heat and pressure should be applied in a negative pressure in the mold or vacuum pack. In the case where the voids are present in the precursor of the resin part (A), which has been generated by heat fusion in advance, the voids are eliminated by heating and vacuum, and the integration method is substantially within a preferable width. It is preferable because a solid resin portion (A) can be obtained. A vacuum / pressure forming method or a vacuum compression molding method is preferred, and specifically, an autoclave method or a mold cavity vacuum compression molding method is preferred.

  An example of the point which manufactures a fiber composite using a thermoforming method is explained concretely. As a manufacturing method of the fiber composite of the present embodiment, a skin material including reinforcing fibers impregnated with a reinforcing synthetic resin is laminated on at least a part of at least one surface of a core material (for example, foam). The heat of the foamed resin contained in the core material is not less than 50 ° C. lower than the glass transition temperature of the reinforcing synthetic resin and 60 ° C. higher than the glass transition temperature of the reinforcing synthetic resin. A compression process in which compression is performed by pressing with a pressure of 0.05 to 1 MPa while heating at a temperature that is 50 ° C. lower than the fusion temperature and 20 ° C. or less higher than the thermal fusion temperature of the foamed resin contained in the core material. And the like. At this time, for example, a vacuum pack in which a laminate is put in advance in an autoclave may be placed, and molding may be performed by applying heat and pressure (pressure air) from outside the vacuum pack while reducing the pressure inside the vacuum pack. In addition, when using a mold during compression, after putting the laminate in the mold cavity, a mechanism that can seal the O-ring, stamping structure, etc. is provided on the parting surface, and the inside of the mold cavity is decompressed. However, the laminate may be heated and compressed on the mold surface.

The compression step is preferably performed such that the compression deformation rate of the foam is 5 to 40%, more preferably greater than 25% and less than 40%.
The compression deformation rate is 30% when the thickness of the molded product before the compression step is 10 mm and the thickness of the molded product after the compression step is 7 mm. The compression deformation rate can be controlled by the heating temperature of the laminate and the pressing pressure. In addition, the heating temperature of a laminated body means the surface temperature of the skin material of a laminated body. Adhesion is improved when the heating temperature is not less than 50 ° C. lower than the glass transition temperature of the reinforcing synthetic resin and not more than 60 ° C. higher than the glass transition temperature because sufficient curing can be obtained within the curing time. However, the rigidity is preferably maintained in a high temperature environment of 100 ° C. Furthermore, the heating temperature is also related to the heat fusion temperature of the foamed resin contained in the core material, and it is preferable that the temperature is 40 ° C. lower than the heat fusion temperature and 20 ° C. lower than the heat fusion temperature. In addition, the average aspect ratio of the bubbles of the core material and the shape of the bubbles are appropriately maintained, the adhesion at the interface of the laminate is extremely high, and the rigidity is preferably maintained in a high temperature environment of 100 ° C. If compression is performed at a temperature higher than 20 ° C. higher than the heat-sealing temperature of the foamed resin contained in the core material, the core material melts, and bubbles in the core material burst and disappear. More preferably, the temperature is 30 ° C. lower than the thermal fusion temperature of the foamed resin contained in the core material, or 10 ° C. lower than the thermal fusion temperature of the foamed resin contained in the core material.

  Further, the pressure is preferably 0.05 to 1 MPa, more preferably 0.1 to 0.7 MPa. When the pressing is in this range, the surface appearance of the fiber composite is good, the resin part (A) is thick, and the strength at high temperature is high, which is preferable.

  Although the pressing time depends on the heating temperature, the resin part can be removed by continuing to apply pressure in a state in which the voids present in the core material are removed and the core material is softened to the extent that bubbles of the foam are not ruptured. In order to form (A), it is preferably longer than 1 hour and shorter than 10 hours.

  In the actual situation of the present invention, the core material (preferably, foam) has low thermal conductivity because it contains bubbles, so that the central portion of the core material is hardly heated. Therefore, it is preferable to perform a preheating process on the laminated body on the conditions which do not apply a pressure before a compression process. By carrying out such a preheating step, it becomes possible to soften the inside and the surface of the core material appropriately without causing bubbles to break. In the compression step, the reinforcing synthetic resin impregnated in the reinforcing fibers can be appropriately softened by heating the laminate at a predetermined temperature. And by compressing a laminated body, performing such a heating, a core material can be pressed to the whole surface of a thickness direction and a surface direction, deform | transforming along a core material surface. Thereby, it becomes possible to further improve the weldability of the pre-expanded particles.

  When the uncured thermosetting resin is contained in the reinforcing synthetic resin impregnated into the reinforcing fiber, preferably, the fiber reinforced plastic layer forming material is adjusted by adjusting the heating of the laminate in the compression step. Maintain the fluidity without curing the uncured thermosetting resin, deform the fiber reinforced plastic layer forming material along the foam surface, and then adjust the heating time of the laminate. By advancing the curing reaction of the uncured thermosetting resin, the thermosetting resin can be cured and the reinforcing fibers can be bonded and integrated with each other. A skin material impregnated with can be formed. When a thermoplastic resin is used as the reinforcing synthetic resin to be impregnated into the reinforcing fiber, the thermoplastic resin is cooled and solidified by cooling the laminated body after the laminated body is heated in the compression step. The reinforcing fibers can be bonded and integrated to form a skin material containing a fiber and a resin obtained by impregnating the reinforcing fiber with a thermoplastic resin on the core material.

  In addition, when making the vacuum pack or mold cavity decompress, it is preferable to make the vacuum as much as possible in order to closely adhere the large void or skin material in the foamed resin to the core material and improve the appearance and thickness accuracy, When the mold cavity is evacuated, the sealing performance must be reinforced, and the durability of the mold sealing performance is not good. Therefore, the gauge pressure is preferably -0.1 MPa to -0.01 MPa. More preferably, it is -0.8 MPa to -0.01 MPa.

  In the method of this embodiment, it is preferable to use a laminate in which a fiber reinforced plastic layer forming material including reinforcing fibers impregnated with a synthetic resin is laminated on at least one surface of the core material described above. The surface of the core material on which the fiber reinforced plastic layer forming material is laminated may be determined according to the use of the obtained fiber composite, and is not particularly limited. Therefore, the fiber reinforced plastic layer forming material may be laminated only on one surface of the core material. Among these, considering the impact resistance of the obtained fiber composite, it is preferable to laminate a fiber reinforced plastic layer forming material on both sides of the core material.

  Since the core material is compressed in the fiber composite of this embodiment, the thickness needs to be adjusted. The thickness can be adjusted by adjusting the degree of pressurization to the laminate. For example, as a method of adjusting the compressive deformation rate of the core material, a method of adjusting the pressing force applied to the laminated body by these pressing members by sandwiching the laminated body in the thickness direction by a pressing member, or the like is used. At this time, it is preferable to arrange the spacers on the outer side of the laminated body, for example, outside both end portions in the width direction or the length direction of the laminated body. By adjusting the height of the spacer, it is possible to easily adjust the degree of pressurization to the laminate and the compression deformation rate of the foam.

  In the case of using a spacer, the spacer may be disposed outside the laminated body. For example, the spacer may be disposed at least outside both ends in the width direction or the length direction of the laminated body, and both ends in the width direction of the laminated body. Spacers may be arranged on both the outer side and the outer side of both ends in the length direction.

  Moreover, a fiber composite having a desired thickness can be obtained by using a mold having a vacuum mold cavity structure in consideration of a certain volume and thickness.

  As described above, by heating and compressing the laminate in the compression step, a fiber composite having a core material and a skin material that is laminated and integrated on at least one surface of the core material and includes fibers and a resin is obtained. It is done.

  The skin material is laminated and integrated only on one surface of the core material by cutting the core material contained in the fiber composite at the center in the thickness direction after the compression process as described above. A fiber composite can be obtained.

  Although there is no restriction | limiting in particular in the thickness of the fiber composite of this embodiment, 0.5 mm-500 mm are preferable. The thickness is determined by the thickness of the foam, which is the skin material and the core material, but if the desired thickness cannot be obtained when the skin material and the core material are integrally molded under pressure, the thickness of the core material is determined. By adjusting, it becomes possible to obtain a desired thickness.

The fiber composite of this embodiment preferably has a bending strength at 23 ° C. of 110 to 140 MPa. Moreover, it is preferable that the bending strength in 100 degreeC is 80-120 MPa, More preferably, it is 90-120 MPa. The difference between the bending strength at 23 ° C. and the bending strength at 100 ° C. is preferably within 40 MPa.
In addition, the bending strength at 23 ° C. and the bending strength at 100 ° C. can be measured by the methods described in Examples described later.

  In the fiber composite of this embodiment, the core material including the foamed resin has the above-described core layer and surface layer, so that the impact resistance is improved while maintaining the rigidity of the skin material in a high temperature environment. Has been. Therefore, although such a fiber composite is not particularly limited, it is suitably used as a structural member of an aircraft, an automobile, a ship, a building, or the like or a casing of an electronic device.

  EXAMPLES Hereinafter, although this invention is demonstrated based on an Example and a comparative example, this invention is not limited to these.

A method for measuring physical properties of the core material before lamination is shown below.
(A) Density About the obtained core material, the weight W (kg) was measured, and then the apparent volume Va (m ³ ) of the core material was measured by a submerging method. The value W / Va (kg / m ³ ) obtained by dividing the weight W by the apparent volume Va was defined as the density of the core material before lamination.

(B) Closed cell ratio About the core material which measured apparent volume Va in above-mentioned (A), the true volume (Vx) was measured using the air comparison type hydrometer (made by Beckman Co., Ltd.). And according to Formula (3), the closed cell rate S (%) was computed.
S (%) = {(Vx−W / ρ) / (Va−W / ρ)} × 100 (3)
Where Vx is the true volume (cm ³ ) of the core material, Va is the apparent volume (cm ³ ) of the core material, W is the weight (g) of the core material, and ρ is The density (g / cm ³ ) of the base material resin of the core material.

(C) Fusing rate Length: 300 mm, width: 300 mm, thickness: 20 mm A cut line with a depth of 5 mm is placed on the surface of a plate-like core material so as to be equally divided into two vertically using a cutter knife, The core material was divided along this line. Regarding the pre-expanded particles appearing on the divided surfaces, the number (a) of the pre-expanded particles broken in the particles (the pre-expanded particles are broken by the divided surfaces) and the interface between the pre-expanded particles And measuring the number (b) of the pre-expanded particles (the interface between the pre-expanded particles is a split surface) and calculating the fusion rate (%) of the core material before lamination according to the following formula (4) did.
Fusing rate (%) = {a / (a + b)} × 100 (4)

(D) Thermal fusion temperature The pre-expanded particles of the obtained foamed resin were brought into a state where the pressure inside the bubbles was atmospheric pressure and no foaming agent such as hydrocarbon was included. 10 g of the pre-expanded particles were placed in a metal mesh container so that the pre-expanded particles were in contact with each other, and then heated with saturated steam at a predetermined temperature for 30 seconds. Then, the lowest temperature (° C.) among the temperatures at which 80% or more of the pre-expanded particles were fused together after heating was defined as the heat fusion temperature (° C.) of the pre-expanded particles.

  The evaluation methods (1) to (6) for fiber composites obtained in Examples and Comparative Examples described later will be described below.

(1) The width of the resin part (A), the width of the resin part (B), the average major axis of the bubbles (C) The fiber composite is cut in the thickness direction, and the cut surface is 100 times using a scanning electron microscope. Taken with Measurement was performed while shifting the sample from the upper skin material to the lower skin material, and the images were laminated to form one image. On the obtained cut surface, the distance between the outer circumferences of the bubbles was measured, and the presence or absence of the resin part (A) and the resin part (B) was observed. Further, in the photographed image of the obtained cut surface, the resin part (A) in the core material is randomly selected at 30 locations, the width thereof is measured, and the average of the resin part (A) is calculated from the arithmetic mean value. The width.
Next, 30 portions of the resin portion (B) were similarly selected at random, the width was measured, and the average width of the resin portion (B) was determined from the arithmetic average value.
Next, 30 air bubbles (C) of the core material are also randomly selected, two arbitrary points having the maximum mutual distance are selected on the outer contour line of the bubble cross section, and the distance between the two points is “ The “major diameter of the bubbles” was measured, and the average major diameter of the bubbles (C) was determined from the arithmetic mean value.
In addition, in the said cut surface, when the bubble which the cross section exposed on the core material surface exists, such a bubble was excluded from the measuring object. For example, when an unfoamed skin is cut and removed from the core material, there is a possibility that bubbles having a cross-section exposed on the surface of the core material.
Also, from the upper skin material side to the lower skin material side, check if the resin part (A) is continuously connected in the thickness direction by looking at the photographed image, and if it is connected, "○" The case where no connection was made was indicated as “x”.
If the resin part (B) and the bubble (C) are surrounded by the resin part (A), check the captured image in the same way. Was marked “x”.
The upper side indicates the upper surface when a horizontally placed sample is installed in the vertical press when integrating with the skin material, and the lower side indicates the lower surface.
The results are shown in Table 1.

(2) Apparent density of core material After the core materials of the fiber composites obtained in the examples and comparative examples were cut out in a cubic shape and the weight W (kg) was measured, three sides of the core material were measured with calipers. The volume V (m ³ ) was calculated. The ratio of weight W to volume V (W / V) (kg / m ³ ) was set as the apparent density.
The results are shown in Table 1.

(3) Bending strength Based on JIS K7221, the bending strength (MPa) of the fiber composite obtained by the Example and the comparative example was calculated | required. Specifically, ten test pieces were cut out from the obtained sample in a size of 100 mm long × 15 mm wide × thickness (obtained sample thickness). As a standard condition, five test pieces that were allowed to stand for 24 hours in a room controlled at a temperature of 23 ° C. and a relative humidity of 50% were used for measurement with AUTOGRAPH AG-5000D (manufactured by Shimadzu Corporation) and specified in JIS. The bending strength (at 23 ° C. atmosphere) (MPa) was calculated from the calculation formula to calculate the average. Further, as a standard state, a test piece which was allowed to stand for 24 hours in a room controlled at a temperature of 23 ° C. and a relative humidity of 50% and then left at 100 ° C. for 1 hour in a thermostatic bath was adjusted to 100 ° C. In a thermostat, five samples were used for measurement with AUTOGRAPH AG-5000D (manufactured by Shimadzu Corporation), bending strength (under an atmosphere of 100 ° C.) (MPa) was calculated from a calculation formula prescribed in JIS, and an average was obtained.
The results are shown in Table 1.

(4) Appearance The surfaces of the fiber composites obtained in the examples and comparative examples were visually observed, and the state of the surface layer was evaluated as follows.
The results are shown in Table 1.
A (Excellent): The resin of the skin material is sufficiently cured, and the surface of the fiber composite is free from resin shortage and unevenness.
○ (good): The resin of the skin material is sufficiently cured, but some unevenness and distortion are observed on the surface of the fiber composite. X (bad): The resin of the skin material enters the core material side, and the fiber composite. The surface of the fiber has exposed fibers and irregularities due to insufficient resin. Shrinkage of the foamed resin occurs, and the surface has irregularities and distortions.

(5) Thickness The thickness (mm) of the fiber composites obtained in the examples and comparative examples was measured using calipers.
The measurement location was obtained by measuring the central part of the outer periphery of the four sides 10 mm inside and averaging the four points. At the center of the sheet, the intersection of the diagonal lines of the sheet was measured.
Moreover, the total thickness (mm) of the skin material laminated | stacked on the upper surface layer and the skin material laminated | stacked on the lower surface layer was measured using calipers.
The results are shown in Table 1.

Example 1
A cross prepreg comprising a carbon fiber having a tensile modulus of 250 GPa and an epoxy resin having a glass transition temperature after curing of 130 ° C. and having a fiber basis weight of 200 g / m ² and a carbon fiber content of 60% by mass ( A product name “Pyrofil TR3110 381FMX” (manufactured by Mitsubishi Rayon Co., Ltd.) was prepared, and one sheet for each of the front and back surfaces was prepared.
Next, a polyamide resin foam as a core material was prepared by the following method.
100 parts by mass of nylon 6 (trade name: UBE nylon 1022B, manufactured by Ube Industries, Ltd.) as a polyamide-based resin, 0.8 parts by mass of talc as a nucleating agent, hindered phenol-based antioxidant (Irganox 1098, manufactured by BASF) 0.3 parts by mass was melt-kneaded under heating conditions with a single screw extruder, then extruded into a strand shape, water-cooled in a cold water tank, and cut to produce a pellet-shaped base resin.
To this, carbon dioxide gas as a foaming agent was contained in the base resin in accordance with the method described in Examples of JP 2011-105879 A. Then, the base resin including carbon dioxide gas was heated to cause foaming to obtain pre-expanded particles having a density of 300 kg / m ³ .
By enclosing the obtained pre-expanded particles in an autoclave and introducing compressed air over 1 hour until the pressure in the autoclave becomes 0.5 MPa, and then holding the pressure at 0.5 MPa for 24 hours, The pre-expanded particles were subjected to pressure treatment.
The pre-expanded particles subjected to the pressure treatment were attached to an in-mold foam molding machine (the cavity size of the mold for in-mold molding is vertical: 300 mm, horizontal: 300 mm, height: 10 mm). Thereafter, pre-expanded particles are filled, and then 135 ° C. saturated steam is supplied into the cavity for 10 seconds (first stage heating), and 144 ° C. saturated steam is supplied into the cavity for 30 seconds (two In the heating step, the pre-foamed particles were foamed and thermally fused to form a foam having a density of 200 kg / m ³ using the pre-foamed particles.
The obtained molded body was cooled by supplying cooling water into the cavity of the mold, and then the mold was opened to take out the polyamide resin foam as the core material.
The obtained foam is used as a core material, and a skin material is laminated on each of the upper and lower surfaces of the core material, a perforated film and a breather cloth are laminated on both surfaces, and this laminated body is made of 10 mm thick aluminum. Place the laminate into a vacuum pack with a tube that can be depressurized by connecting it to a vacuum pump and connecting the vacuum pump to the vacuum pack, and sealing the vacuum pack with a gauge pressure of -0.07 MPa. Continue to depressurize. Next, this was put into an autoclave for composite material heat curing test (small-sized autoclave DANDELION manufactured by Haneda Iron Works), and the temperature in the autoclave was held at 90 ° C. and a pressure of 0.3 MPa for 6 hours.
In addition, the fiber composite obtained in Example 1 is a fiber composite in which a skin material is laminated on both surfaces of 300 × 300 mm of the surface layer of the core material. The obtained sample was cut with a cut saw, cross-sectional observation was performed, a strip was further created, and the bending strength was measured. The fiber composite had a good bending elastic modulus and a good appearance both in the standard state and in a high temperature environment of 100 ° C.
Details of Example 1 are shown in Table 1.

(Example 2)
A fiber composite was obtained under the same conditions as in Example 1, except that the temperature in the autoclave for composite material heat curing test was held at 140 ° C. and a pressure of 0.3 MPa for 1.5 hours.
In the same manner as in Example 1, cross-sectional observation and bending strength were measured. Further, the obtained fiber composite had a good flexural modulus and a good appearance both in the standard state and in a high temperature environment of 100 ° C. Details of Example 2 are shown in Table 1.

Example 3
After obtaining pre-expanded particles having a density of 200 kg / m ³ as in Example 2, the obtained pre-expanded particles were sealed in an autoclave, and compressed air was added until the pressure in the autoclave reached 0.5 MPa. Introducing the pressure over a period of time, and then maintaining the pressure at 0.5 MPa for 24 hours, followed by heating at 230 ° C. to cause further foaming, density: 120 kg / m A foam and a fiber composite were obtained in the same manner as in Example 2 except that the foam of ³ was obtained. Details of Example 3 are shown in Table 1.

(Example 4)
Manufacture and evaluation were performed in the same manner as in Example 1 except that a polyamide resin foam as a core material was prepared by the following method.
Nylon 666 (nylon 66/6) (trade name: Novamid 2430A, manufactured by DSM Co., Ltd.) as a polyamide-based resin, 100 parts by mass, talc as a nucleating agent, 0.8 parts by mass, hindered phenol antioxidant (Irganox 1098, 0.3 parts by mass (made by BASF) was melt-kneaded under heating conditions in an extruder, then extruded into a strand shape, water-cooled in a cold water tank, and cut to produce a pellet-shaped base resin.
To this, carbon dioxide gas as a foaming agent was contained in the base resin in accordance with the method described in Examples of JP 2011-105879 A. Then, the base resin containing carbon dioxide gas was heated to cause foaming to obtain pre-expanded particles having a density of 200 kg / m ³ .
By enclosing the obtained pre-expanded particles in an autoclave and introducing compressed air over 1 hour until the pressure in the autoclave becomes 0.4 MPa, and then holding the pressure at 0.4 MPa for 24 hours, The pre-expanded particles were subjected to pressure treatment.
After pressurizing the pre-expanded particles, using the mold expansion molding machine used in Example 1, the mold was clamped, and then the pre-expanded particles were filled. By supplying for 2 seconds, the pre-foamed particles were foamed and heat-sealed to form a foam having a density of 200 kg / m ³ using the pre-foamed particles.
The obtained molded body was cooled by supplying cooling water into the cavity of the mold, and then the mold was opened to take out the polyamide resin foam as the core material.
Using the obtained foam as a core material, the same conditions as in Example 1 were applied to Example 1 except that the temperature in the autoclave for composite material heat curing test was held at 130 ° C. and a pressure of 0.3 MPa for 3 hours. A fiber composite was obtained. The fiber composite had a good flexural modulus and a good appearance both in the standard state and in a high temperature environment of 100 ° C.
Details of Example 4 are shown in Table 1.

(Example 5)
Polyphenylene ether resin (PPE) (Asahi Kasei Corporation, S201A) 60% by mass, non-halogen flame retardant (bisphenol A-bis (diphenyl phosphate) (BBP)) 18% by mass, rubber concentration 6% by mass 10% by mass of impact-resistant polystyrene resin (HIPS) (content of rubber component in the base resin is 0.6% by mass), 12% by mass of general-purpose polystyrene resin (PS) (manufactured by PS Japan, GP685), Using 0.8 parts by mass of talc as a nucleating agent and 0.3 parts by mass of a hindered phenol antioxidant (Irganox 1098, manufactured by BASF), these are extruded after heating and melt-kneading in an extruder, and a base material as a core material Resin pellets were prepared. According to the method described in Example 1 of JP-A-4-372630, the base resin pellets are accommodated in a pressure resistant container, and the gas in the container is replaced with dry air, and then carbon dioxide gas (gas) is used as a foaming agent. The base resin pellets were impregnated with 7% by mass of carbon dioxide gas under conditions of a pressure of 3.2 MPa and a temperature of 11 ° C. over 3 hours.
Thereafter, the base resin pellets were foamed with pressurized steam while rotating the stirring blades at 77 rpm in the prefoaming machine to obtain prefoamed particles.
The pre-expanded particles were pressurized to 0.5 MPa over 1 hour, then held at 0.5 MPa for 8 hours, and subjected to pressure treatment.
The pre-expanded particles that had been subjected to pressure treatment were filled into cavities (cavity dimensions: longitudinal: 300 mm, lateral: 300 mm, height: 10 mm) of the in-mold molding die, and then clamped. And this metal mold | die was attached to the in-mold foam molding machine.
Thereafter, 125 ° C. saturated water vapor is supplied into the cavity for 10 seconds (first stage heating), and then 130 ° C. saturated water vapor is supplied into the cavity for 30 seconds (second stage heating), and the pre-expanded particles The pre-expanded particles were formed by foaming and heat-sealing.
The obtained molded body was cooled by supplying cooling water into the cavity of the mold, and then the mold was opened to take out a polyphenylene ether-based resin foam as a core material.
Using the obtained foam as a core material, the same conditions as in Example 1 were applied to Example 1, except that the temperature in the autoclave for composite material heat curing test was held at 80 ° C. and pressure 0.3 MPa for 6 hours. A fiber composite was obtained.
The fiber composite obtained in Example 5 is a fiber composite in which a skin material is laminated on the entire surface layer of the core material. Details of Example 5 are shown in Table 1.

(Example 6)
70 parts by weight of methyl methacrylate (MMA), 10 parts by weight of styrene (ST), 20 parts by weight of maleic anhydride (MAH), 0.8 parts by weight of talc, hindered phenol antioxidant (Irganox 1098, manufactured by BASF) 3 parts by weight, 0.3 parts by weight of lauroyl peroxide as an initiator, and 10 parts by weight of n-butanol as a foaming agent at room temperature for 10 minutes, and then on the plane of a glass plate having a length of 500 mm and a thickness of 10 mm each, Place a 15 mm silicone rubber O-packing near the edge of the glass plate, fill the monomer solution in the O-packing, and place another glass plate on top of the O-packing and monomer solution. Tighten the clips evenly so that the thickness is 12mm by using multiple clips that can be adjusted around the glass as if sandwiched by glass Digits. It was immersed in a hot water bath at 60 ° C. for 24 hours. Thereafter, it was taken out, cured in an oven at 130 ° C. for 1 hour, then cooled to room temperature, the clip and the glass plate were removed, and the O packing was cut and deleted to obtain a special acrylic resin plate. The special acrylic resin was pulverized by a pulverizer and classified to obtain 2 mm pulverized particles. The pulverized fine particles were placed in an explosion-proof oven at 150 ° C. for 60 minutes to cause foaming and taken out to obtain pre-foamed particles having a density of 200 kg / m ³ .
By enclosing the obtained pre-expanded particles in an autoclave and introducing compressed air over 1 hour until the pressure in the autoclave becomes 0.5 MPa, and then holding the pressure at 0.5 MPa for 24 hours, The pre-expanded particles were subjected to pressure treatment.
The pre-expanded particles that had been subjected to pressure treatment were filled into cavities (cavity dimensions: longitudinal: 300 mm, lateral: 300 mm, height: 10 mm) of the in-mold molding die, and then clamped. And this metal mold | die was attached to the in-mold foam molding machine.
Thereafter, 110 ° C. saturated water vapor is supplied into the cavity for 10 seconds (first stage heating), and then 120 ° C. saturated water vapor is supplied into the cavity for 30 seconds (second stage heating) to produce pre-expanded particles. The pre-expanded particles were formed by foaming and heat-sealing.
The obtained molded body was cooled by supplying cooling water into the cavity of the mold, and then the mold was opened to take out an acrylic resin foam as a core material.
The same conditions as in Example 1 except that the obtained foam was used as a core material and the temperature in the autoclave for composite material heat curing test was held at 110 ° C. and a pressure of 0.3 MPa for 4 hours with respect to Example 1. A fiber composite was obtained.
The fiber composite obtained in Example 6 is a fiber composite in which a skin material is laminated on the entire surface layer of the core material. Details of Example 6 are shown in Table 1.

(Example 7)
100 parts by mass of polyethylene terephthalate (PET, trade name “SA-135” manufactured by Mitsui Chemicals), a master batch comprising polyethylene terephthalate containing talc (polyethylene terephthalate content: 60% by mass, talc content: 40% by mass) A polyethylene terephthalate composition containing 1.8 parts by mass, pyromellitic anhydride 0.2 parts by mass, and hindered phenol antioxidant (Irganox 1098, manufactured by BASF) 0.3 parts by mass was 290 ° C. in a single screw extruder. Melting and kneading under heating conditions, and then injecting into the polyethylene terephthalate composition in a molten state so that normal butane is 0.8 parts by mass with respect to 100 parts by mass of polyethylene terephthalate from the middle of the extruder. It was uniformly dispersed in terephthalate.
After that, after cooling the molten polyethylene terephthalate composition to 280 ° C. at the front end of the extruder, it is melt-kneaded under heating conditions in a single-screw extruder, then extruded into a strand, and water-cooled in a cold water tank. Then, cutting was performed to obtain pre-expanded particles having a pellet shape density of 400 kg / m ³ .
By enclosing the obtained pre-expanded particles in an autoclave and introducing compressed air over 1 hour until the pressure in the autoclave becomes 0.5 MPa, and then holding the pressure at 0.5 MPa for 24 hours, The pre-expanded particles were subjected to pressure treatment.
The pre-expanded particles that had been subjected to the pressure treatment were filled into cavities (cavity dimensions: length: 300 mm, width: 300 mm, height: 10 mmt) of the in-mold mold, and then the mold was clamped. And this metal mold | die was attached to the in-mold foam molding machine.
Then, 120 ° C. saturated water vapor is supplied into the cavity for 10 seconds (first stage heating), and then 130 ° C. saturated water vapor is supplied into the cavity for 30 seconds (second stage heating), and pre-expanded particles The pre-expanded particles were formed by foaming and heat-sealing.
The obtained molded body was cooled by supplying cooling water into the cavity of the mold, and then the mold was opened to take out a PET resin foam as a core material.
Using the obtained foam as a core material, the same conditions as in Example 1 were applied to Example 1 except that the temperature in the autoclave for composite material heat curing test was held at 120 ° C. and a pressure of 0.3 MPa for 3 hours. A fiber composite was obtained. Details of Example 7 are shown in Table 1.

(Example 8)
As a raw material, polycarbonate resin powder synthesized as follows was used as a raw material. After dissolving 710 parts by mass of 2,2-bis (4-hydroxyphenyl) propane (hereinafter sometimes referred to as “bisphenol A”) (bisphenol A solution), 2299 parts by mass of methylene chloride and 48.5% by mass of hydroxide A phosgenation reaction was performed by adding 112 parts by mass of an aqueous sodium solution and blowing 354 parts by mass of phosgene over 15 minutes at 15 to 25 ° C. After the completion of phosgenation, 148 parts by mass of 11% by mass p-tet-butylphenol methylene chloride solution and 88 parts by mass of 48.5% by mass sodium hydroxide aqueous solution were added, stirring was stopped, and the mixture was left to stand for 10 minutes The mixture was stirred and emulsified, and after 5 minutes, it was treated with a homomixer (Special Machine Industries Co., Ltd.) at a rotation speed of 1200 rpm and a pass count of 35 times to obtain a highly emulsified dope. The highly emulsified dope was reacted in a polymerization tank (with a stirrer) at a temperature of 35 ° C. for 3 hours under non-stirring conditions to complete the polymerization. After completion of the reaction, the organic phase is separated, diluted with methylene chloride, washed with water, acidified with hydrochloric acid, washed with water, and poured into a kneader filled with warm water when the conductivity of the aqueous phase is almost the same as that of ion-exchanged water. Then, methylene chloride was evaporated with stirring to obtain polycarbonate powder. After dehydration, it was dried at 120 ° C. for 12 hours with a hot air circulation dryer to obtain a polycarbonate resin powder.
High-molecular-weight acrylic resin (manufactured by Mitsubishi Rayon Co., Ltd., trade name “METABBRENE P-530A”, weight average molecular weight 3 million) 1 A single screw extruder using a polycarbonate resin composition containing 0.1 parts by mass and 0.1 parts by mass of an air conditioner (polytetrafluoroethylene powder) and 0.3 parts by mass of a hindered phenol antioxidant (Irganox 1098, manufactured by BASF) The mixture was melt-kneaded under a heating condition of 300 ° C. and then extruded into a strand, cooled in a cold water tank, and cut to produce a pellet-shaped base resin.
The obtained base resin is accommodated in a pressure-resistant container, and the gas in the container is replaced with dry air. Then, carbon dioxide gas (gas) is injected as a foaming agent, and the pressure is 3.0 MPa and the temperature is 11 ° C. Over time, the base resin pellet was impregnated with 7.5% by mass of carbon dioxide. The base resin containing carbon dioxide gas was heated with heated steam to cause foaming, and pre-expanded particles having a density of 200 kg / m ³ were obtained. Thereafter, 125 ° C. saturated water vapor is supplied into the cavity for 10 seconds (first stage heating), and then 130 ° C. saturated water vapor is supplied into the cavity for 30 seconds (second stage heating), and the pre-expanded particles The pre-expanded particles were formed by foaming and heat-sealing.
The obtained molded body was cooled by supplying cooling water into the cavity of the mold, and then the mold was opened to take out a polycarbonate resin foam as a core material.
Using the obtained foam as a core material, the same conditions as in Example 1 were applied to Example 1 except that the temperature in the autoclave for composite material heat curing test was held at 120 ° C. and a pressure of 0.3 MPa for 3 hours. A fiber composite was obtained. Details of Example 8 are shown in Table 1.

(Comparative Example 1)
The temperature of a 50 mmφT die twin screw extruder having an L / D of 40 was set to 280 ° C. for the polycarbonate resin composition used in Example 8, the raw material was charged from the hopper, and liquefied normal butane was added at a pressure of 1 MPa in the middle of the barrel. Pressure injection was performed, and the polycarbonate resin foamed at the T-die outlet, and normal butane was vaporized. A foamed resin having a thickness of 10 mm and a width of 400 mm was obtained by sandwiching the foamed resin coming out from above and below with a stainless steel seam belt from the outlet. The thickness was 10 mm by adjusting the lip gap of the T die and the gap between the upper and lower stainless steel seam belts. As for the width, a width of 400 mm was obtained by using a T die having a 400 mm wide T die.
Using the foam obtained by cutting out 300 × 300 × 10 mm from the obtained foam sheet as the core material, using the obtained foam as the core material, the temperature in the autoclave for the composite material heat curing test with respect to Example 1 Was held at 120 ° C. under a pressure of 0.3 MPa for 3 hours to obtain a fiber composite under the same conditions as in Example 1. Details of Comparative Example 1 are shown in Table 1.

(Comparative Example 2)
The pre-expanded particles having a density of 200 kg / m ³ obtained in Example 8 were attached to an in-mold foam molding machine (cavity dimensions of a mold for in-mold molding were 300 mm in length, 300 mm in width, 300 mm in width, (The height is 10 mm) After the mold is clamped, the pre-expanded particles are filled, and then, saturated steam at 125 ° C. is supplied into the cavity for 20 seconds, and the pre-expanded particles are expanded and heat-sealed. Thus, a foam was formed.
Using the obtained foam as a core material, a fiber composite was prepared under the same conditions as in Example 1, except that the temperature in the autoclave was held at 80 ° C. and a pressure of 0.3 MPa for 0.5 hours. Obtained. Details of Comparative Example 2 are shown in Table 1.

  About Examples 1-8, the bending strength in 23 degreeC and 100 degreeC atmosphere was high, and the result and the thickness of the fiber composite_body | complex were good. On the other hand, in Comparative Example 1, the thickness of the resin portion (A) is almost the same as that of the resin portion (B) and is thin, and therefore it is determined that there is no resin portion (A). Therefore, the resin part (A) is not connected, and the resin part (B) and the bubble (C) are not surrounded by the resin part (A), resulting in low bending strength in an atmosphere of 100 ° C. . Moreover, the middle thickness of the fiber composite was thick, and the surface was distorted like a drum. In Comparative Example 2, it is determined that the resin part (A) is thin because the time during the thermal welding of the expanded particles and the autoclave molding is insufficient, and therefore there is no resin part (A). Moreover, there are many places where the resin part (A) is not connected, resulting in low bending strength in a 100 ° C. atmosphere. Moreover, the thickness of the middle of the fiber composite was thin and the surface was distorted.

  The fiber composite of the present embodiment is excellent in excellent rigidity and aesthetic appearance in a high-temperature environment such as 100 ° C., and surface cosmetics at the time of high-temperature molding. The fiber composite of the present invention can be suitably used particularly in the automobile field.

1 Fiber Composite 2 Core Material 3 Skin Material 4 Resin Part (A)
5 Resin part (B)
6 Bubble (C)

Claims (4)

A fiber composite comprising a core material containing a foamed resin, and a skin material containing fibers and resin laminated on at least a part of the surface of the core material;
In the cross section in the thickness direction of the fiber composite, the core includes a resin portion (A) having a width of 8 μm or more and bubbles (C) having an average major axis of 5 to 800 μm. .   2. The fiber composite according to claim 1, wherein in the cross section, at least a part of the resin portion (A) is continuously connected from one surface of the core material to the other surface.   The fiber composite according to claim 1 or 2, wherein the cross section includes a structure in which a plurality of the bubbles (C) are surrounded by the resin portion (A).   The fiber composite according to any one of claims 1 to 3, wherein the foamed resin is a polyamide-based resin or a polyphenylene ether-based resin.

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