WO1994016003A1

WO1994016003A1 - Prepreg, method of manufacturing the same, and laminated composite

Info

Publication number: WO1994016003A1
Application number: PCT/JP1993/001882
Authority: WO
Inventors: Atsushi Ozaki; Hajime Kishi; Nobuyuki Odagiri; Hiroki Oosedo; Hiroaki Ninomiya
Original assignee: Toray Industries, Inc.
Priority date: 1993-01-14
Filing date: 1993-12-24
Publication date: 1994-07-21
Also published as: KR950700350A; DE69326059D1; DE69326059T2; JP3387100B2

Abstract

A prepreg consisting of the following constituent elements: (A), (B) and (C), and the constituent element (C) is distributed in the portion of the prepreg which is close to a superficial layer of one or both surfaces thereof, the constituent element (C) not having regular arrangement (A) reinforced fibers consisting of long fibers; (B) matrix resin; (C) long fibers of a thermoplastic resin. The prepreg according to the present invention gives a composite material retaining its tacking characteristics and draping characteristics and its thermal resistance when it is hot formed, and having excellent impact resistance and inter-layer tenacity. This prepreg is manufactured easily, and has a high degree of freedom as a material.

Description

Specification

Pre-preder, method for producing the same, and laminated composite

Technical field

The present invention relates to a pre-preder used for producing a fiber reinforced plastic having excellent strength, elastic modulus, impact resistance and interlaminar toughness. Fiber-reinforced plastic, which is a type of composite material, is an anisotropic material that contains reinforced fibers and matrix resin as essential components, and there is a large difference between the physical properties in the fiber axis direction and those in the other directions. Generally, the strength and elastic modulus in the fiber axis direction are extremely high, but they take low values in other directions.

In the production of fiber-reinforced plastics, a method is widely used in which a film-shaped precursor called a preplader, in which uncured thermosetting resin is impregnated in reinforced fibers, is laminated, molded, and then cured to obtain the * t target product. Be done. In the following description, the term “composite material” is used to mean a fiber-reinforced plastic obtained by laminating, molding, and curing a prepender unless otherwise specified.

When a composite material is obtained from a prepreg, the in-plane physical properties can be almost eliminated by using a method of using a prepreg made of reinforcing fibers as a woven fabric or a method of stacking prepregs of reinforcing fibers arranged in one direction by changing the fiber axis direction. Isotropic is done.

However, even with such a structure, the impact resistance of the composite material is dominated by the fracture between the layers, and therefore, improving the strength of the reinforcing fiber may not lead to a drastic improvement. Are known. Here, the interlayer of the composite material means the vicinity of the surface corresponding to the interface between the pre-preders when laminating the pre-preders. In this region, the fraction of the reinforcing fibers is small and the orientation of the reinforcing fibers on both sides of it is different, so it is easy to concentrate the fracture o

In particular, a composite material using a thermosetting resin as a matrix resin has insufficient impact resistance, reflecting the low toughness of the matrix resin. In addition, when a tensile load is applied to a cross-laminated plate, delamination often occurs from the plate edge, which often limits the degree of freedom in the laminated structure. Therefore, various methods have been proposed for the purpose of improving physical properties other than the fiber axis direction, particularly impact resistance and interlayer toughness. In particular, a material different from the matrix resin is arranged between the layers to absorb the fracture energy. There are many proposed methods. U.S. Pat. No. 4,604.9 discloses that impact resistance is improved by placing a thermoplastic resin film between the layers of a fiber reinforced pre-preder. But this place In this case, the thermosetting resin has the disadvantage that the tackiness (adhesiveness) and the drapeability (property to conform to the shape) which are advantages of the thermosetting resin are lost.

The present inventors have disclosed in US Pat. No. 5,028,478 a matrix resin containing fine particles made of oleoresin. In particular, it was shown that by localizing the resin fine particles on the surface of the pre-preder, a composite material having improved impact resistance while maintaining the tackiness and drape of the pre-preder was provided. However, this method also has a problem that it is not so easy to obtain fine resin particles. Further, fine particles penetrate the reinforcing fiber, but the fine particles cause deterioration of the physical properties of the composite material, and trying to avoid this complicates the prepreg manufacturing process. Japanese Unexamined Patent Publication No. 2-32843 discloses that the interlaminar toughness of a composite material is improved by pasting a woven fabric on the surface of a fiber reinforced pre-preder. In general, it is often easier to fiberize the resin than to make it into particles, and this has an advantage, but it is not possible to make full use of this advantage because it is necessary to fabricate the fiber. In addition, there is a manufacturing limit in reducing the basis weight of the woven fabric, and it is not possible to obtain an appropriate basis weight as the interlayer material.

Composite Materials: Testing and Design (Seventh Conference), ASTM STP 89 3 "In a 256-page paper, it was found that the effect of improving interlaminar toughness can be obtained by placing a Kevlar or polyester mat between the layers. However, the production of such mats requires a further step of cutting and matting after the production of fibers, and the advantages of using fibers cannot be fully utilized. There is a limit to the unit weight.

Japanese Unexamined Patent Application Publication No. 2-Japanese Unexamined Patent Publication No. 295-295, Japanese Unexamined Patent Publication No. 2962, Japanese Unexamined Patent Publication No. 4-292909, Japanese Unexamined Patent Publication No. 55, Japanese Unexamined Patent Publication No. 4-325528, Japanese Unexamined Patent Publication No. Japanese Patent Laid-Open No. 17603/1993 discloses that interlaminar toughness of a composite material is improved by arranging a fibrous thermoplastic resin on a surface of a fiber reinforced pre-preder in a certain direction. However, if the fibrous thermoplastic resin is made to have a low basis weight, there is a drawback that unevenness of the basis weight is caused in the width direction of the pre-preder, resulting in large variation in performance. Further, in the case of using the unidirectionally arranged reinforcing fibers, if the fibrous thermoplastic resin is arranged in parallel with the reinforcing fibers, they will penetrate into the reinforcing fibers and impair the physical properties of the composite material.

However, each of these methods has its own drawbacks, such as its impact resistance improvement effect is still insufficient, and interlaminar shear strength, handleability and other properties are sacrificed in order to improve impact resistance. ing. Also, in comparison with conventional prepreders, There is also a problem that the manufacturing process becomes complicated and difficult.

It is an object of the present invention to provide a composite material that is excellent in strength, elastic modulus, impact resistance, and interlaminar toughness, and that is simple and easy to manufacture, and a manufacturing method thereof.

Disclosure of the invention

The present invention has the following configuration to achieve the above object.

Consists of the following constituents [A], [B], and [C]. The constituent [C] is distributed near the surface of one side or both sides, and the constituent [C] is a pre-preder without a regular array.

[A]: Reinforcing fiber consisting of long fibers

[B]: Matrix resin

[C]: Long filament of thermoplastic resin

Further, the present invention has the following configuration to achieve the above object.

This is a method for producing a pre-preder characterized by impregnating the following constituent [A] with the constituent [B] and randomly arranging the constituent [C] from one side or both sides of the constituent [C].

[A]: Reinforcing fiber consisting of long fibers

[B]: Matrix resin

[C]: Long filament of thermoplastic resin

Furthermore, the present invention has the following configuration to achieve the above object.

A composite material consisting of the following components [A], [D], and [C], in which the components [C] are randomly arranged in a plane between the laminated layers.

[A] Reinforcing fiber consisting of long fibers

[D] Matrix resin cured product

[C] Thermoplastic long fibers

BEST MODE FOR CARRYING OUT THE INVENTION

Hereinafter, the present invention will be specifically described.

The element used as the constituent element [A] in the present invention is a reinforcing fiber composed of long fibers, and various elements can be used according to the purpose of use of the composite material. Specific examples of the reinforcing fiber used in the present invention include carbon fiber, graphite fiber, aramid fiber, gay carbon fiber, aluminum fiber, boron fiber, tungsten carbide fiber and glass fiber. The reinforcing fiber may be used in combination of plural kinds. Among these, carbon fiber and graphite fiber, which have good specific strength and specific elastic modulus and are recognized to make a great contribution to weight reduction, are good for the present invention. It is possible to use all types of carbon fibers and graphite fibers depending on the application, but high-strength carbon fibers with a tensile elongation of 1.5 ¾ or more are used to express the strength of the composite material. Are suitable. Tensile strength 450 kgf

, Tensile elongation 1.? High strength and high elongation carbon fibers having a tensile strength of 1.9% or higher are most preferable. Further, although long-fiber-shaped reinforcing fibers are used in the present invention, the length thereof is preferably 5 cm or more. If the length is shorter than that, it becomes difficult to sufficiently develop the strength of the reinforcing fiber as a composite material. Further, carbon fibers and graphite fibers may be used by mixing with other reinforcing fibers.

The shape and arrangement of the reinforcing fibers are not limited, and for example, they can be used in a single direction, a random direction, a sheet shape, a mat shape, a woven shape, or a braided shape. Further, in particular, an array in which reinforcing fibers are aligned in a single direction is most suitable for an application in which high specific strength and high inelasticity are required, but a woven array that is easy to handle is also included in the present invention. Suitable for

The matrix resin used as the constituent element [B] in the present invention is mainly composed of a resin that is cured by heat or energy from the outside such as light or electron beam to form a three-dimensional cured product at least partially. In particular, a so-called thermosetting resin that is cured by heat is preferably used. As the thermosetting resin suitable for the present invention, an epoxy resin is particularly mentioned, and it is generally used in combination with a curing agent or a curing catalyst. In particular, an epoxy resin containing an amine, a phenol, or a compound having a carbon-carbon double bond as a precursor is preferable. Specifically, as an epoxy resin using an amine as a precursor, tetradalycidyl diaminodiphenyl methane, triglycidyl 1-p-aminophenol, liglycidyl m-aminophenol, Epoxy resins using various isomers of triglycidylamino cresol and phenols as precursors, bisphenol A type epoxy resin, bisphenol F type epoxy resin, bisphenol S type epoxy resin, phenol novolak type epoxy resin, Examples of the cresol lunovolak type epoxy resin and the epoxy resin having a compound having a carbon-carbon double bond as a precursor include alicyclic epoxy resins, but are not limited thereto. In addition, brominated epoxy resins obtained by bromizing these epoxy resins are also used. Epoxy resins, which have aromatic aromatic amines such as tetradalycidyl diaminodiphenyl methane as a precursor, have good heat resistance and good adhesion to reinforcing fibers, and are therefore most suitable for the present invention. There is. Epoxy resins are preferably used in combination with epoxy hardeners. As the epoxy curing agent, any compound having an active group capable of reacting with an epoxy group can be used. A compound having an amino group, an acid anhydride group, or an azido group is preferable. Specifically, dicyandiamide, various isomers of diaminodiphenylsulfone, various derivatives of diaminodiphenylmethane, and aminobenzoic acid esters are suitable. Specifically, dicyandiamide is preferred because of its excellent preservability. Further, various isomers of diaminodiphenyl sulfone are most suitable for the present invention because they give a cured product having good heat resistance. An alkyl derivative of diaminodiphenylmethane, particularly a 3,3'5,5'-tetraalkyl derivative, is suitable for the present invention because it gives a cured product having high elongation and low water absorption.

As aminobenzoic acid esters, trimethylenedalicol di-p-aminobenzoate and neopentylglycol di-p-aminobenzobenzoic acid are preferably used and compared with diaminodiphenylsulfone. Although it is inferior in heat resistance, it is superior in tensile elongation, so it is selected and used according to the application.

The thermosetting resin used for the component [B] includes a maleimide resin, a resin having an acetylene terminal, a resin having a nadic acid terminal, a resin having a cyanate ester terminal, a resin having a vinyl terminal, and an aryl group. A resin having is also preferably used. These may be appropriately mixed with an epoxy resin or another resin. In addition, a reactive diluent may be used, or a modifier such as a thermoplastic resin or an elastomer may be mixed and used to such an extent that heat resistance is not significantly deteriorated.

Maleimide resin is a compound containing an average of 2 or more maleimide groups per molecule. Particularly preferred is bismaleimide made from diaminodiphenyl ester. Examples of this type of maleide compound include N, N'-phenylene bismaleimide,, Ν'-hexamethylene bismaleimide, Ν, N'-methylene-di-ρ _phenenium. Lenvy maleimide, Ν, Ν'-oxy-di-Ρ-Phenylene bismaleimide, N, N '-4, 4'- Benzophenone bismaleimide, Ν, N'-Diphenylsulfone bismale Mid, Ν, N'- (3, 3'-Dimethyl) -Methylene-di-ρ-Phenylene Bismaleimid, Ν, N'-4, 4'-Disic Mouth Hexylme Yun Bismalei Mid , Ν, N'- m (or p) -xylylene-bismaleimide, N, N '-(3,3' octyl) -methylene-di-p-phenylene bismaleimide, N, N '- Examples include the reaction products of mixed polyamines, which are the reaction products of aniline and formalin, and maleic anhydride, including the bismalemides of benzene and the diamines. However, the present invention is not limited to this. Also, These maleimide compounds may be used as a mixture of two or more kinds, and also contain mono-maleimide compounds such as N-arylmaleimide, N-propylmaleamide, N-hexylmaleamide and N-phenylmaleimide. You may.

The maleimide resin is preferably used in combination with a curing agent. As the curing agent, any compound having an active group capable of reacting with the maleimide group can be used. A compound having an amino group, an alkenyl group represented by an aryl group, a benzocyclobutene group, an arylnamidimide group, an isocyanate group, a cyanate group, or an epoxy group is suitable. For example, diaminodiphenylmethane is a typical curing agent having an amino group, and 0,0'-diarylbisphenol A or bis (propenylphenoxy) sulfone is a curing agent having an alkenyl group. And so on.

The above-described bismaleimide-triazine resin (BT resin) composed of bismaleamide and cyanate ester is also suitable as the thermosetting resin used in the constituent element [B] of the present invention. As the resin having a cyanate ester terminal, a polyvalent cyanate ester compound represented by bisphenol A is preferable. A resin in which a cyanate ester resin and a bismaleimide resin are combined is commercially available from Mitsubishi Gas Chemical Co., Inc. as a B T resin and is suitable for the present invention. Generally, these have better heat resistance and water resistance than epoxy resins, but are inferior in toughness and impact resistance, so they are selected and used according to the application. It is used in a weight ratio of bismaleimide to cyanate in the range of 0 Z 100 to 70 Z 30. The case of 0 100 corresponds to a triazine resin, which is also suitable for the present invention.

Further, a thermosetting polyimide resin having a terminal reactive group is also suitable as the constituent element [B] of the present invention. As the terminal reactive group, nadiimide group, acetylene group, benzocyclobutene group and the like are preferable.

In addition, the component [B] of the present invention may be a thermosetting resin that has been widely recognized in the industry, such as a fuunol resin, a resorcinol resin, an unsaturated polyester resin, a diaryl phthalate resin, a urea resin, and a melamine resin. Can be used.

In addition to the thermosetting resin, a thermoplastic resin such as polysulfone or polyether imide, inorganic fine particles such as finely powdered silica, and elastomer are mixed in the constituent element [B] of the present invention. It is also possible to modify. In this case, the components other than the thermosetting resin are preferably contained within 35% by weight.

The prepreg of the present invention is laminated and cured using a means such as heat or light to obtain a composite material. In this composite material, the constituent [B] is a constituent component of the resin component produced by curing. Let's say [D].

As the constituent [B] of the pre-preder of the present invention, a resin composition that undergoes phase separation in the process of heating from 10 ° C to 250 ° C can be preferably used. In this case, the constituent [D] of the composite material has a phase-separated structure. Whether or not the resin composition undergoes phase separation can be easily determined by observing with a microscope in the process of heating and heating.

It is further preferable that the component [D] having a phase-separated structure has a structure in which a phase mainly composed of a thermosetting resin and a phase mainly composed of a thermoplastic resin are separated into a mixture phase o

This preferable matrix resin composition is further preferably a resin cured product having a structure in which a phase mainly containing a thermosetting resin and a phase mainly containing a thermoplastic resin are separated into a mixture phase. The constituent [D] is obtained by curing the constituent [B]. It is more preferable that the component [B] has a characteristic microphase-separated structure described below in the process of curing. In other words, a phase containing a thermoplastic resin as a main component exists separately from a phase containing a thermosetting resin as a main component, and at least a phase containing a thermoplastic resin as a main component is three-dimensionally continuous in a mesh pattern. This is the case when there is a structure. Such a structure is obtained by the thermosetting resin and the thermoplastic resin, which have not been cured yet, once forming a uniform compatible state and then phase-separated during the curing process. More preferably, it is a resin cured product having a Miku mouth phase separation structure in which both phases have a three-dimensionally continuous mesh-like structure. In some cases, it is also preferable that the continuous phase contains a dispersed phase of another phase. In particular, it is preferable to have a dispersed phase composed of a rubber phase because it greatly contributes to the improvement of toughness.

The structural period of the continuous phase containing a thermoplastic resin as a main component is more preferably about 0.01 to 20 Mikuguchi. If it is less than 0.01 micron, the unevenness of the fracture surface is shallow and the fracture path is short, making it difficult to develop high toughness. Above 20 micron, the fracture path is simplified and the toughening effect is diminished. More preferably, it is about 0.1 to 10 Miku.

The phase-separated structure of the cured resin can be observed under a microscope by a conventional method. Although it can be observed with an optical microscope, in some cases it is preferable to stain with osmium tetroxide or the like and observe with an electron microscope. The existence of different phases is clear, and at least one phase forms a continuous structure, and if there is a dispersed phase in the continuous phase, its existence can be known. By using a microscope together with an analyzer such as an X-ray micro analyzer, it is possible to identify the constituent elements. Fracture strain energy release rate G of the cured resin of the present invention, ASTM E 399 - 83 stress intensity factor obtained by K _ie and Poisson's ratio 7, G _{1 [lambda} = kappa from flexural modulus E, _c ² (1-§ ² ) Can be calculated according to ZE. Here, the flexural modulus shall be measured according to AS ™ D790.

The thermoplastic resin component in component [B] and component [D] refers to a thermoplastic resin that is widely recognized in the industry, but it does not have the high heat resistance and high elastic modulus inherent to thermosetting resins. Since it does not damage, it belongs to the so-called engineering plastics of aromatic type. It is preferable as this thermoplastic resin. That is, a thermosetting resin-soluble high heat-resistant thermoplastic resin having an aromatic polyimide skeleton, an aromatic polyamide skeleton, an aromatic polyether skeleton, an aromatic polysulfone skeleton, and an aromatic polyketone skeleton is a typical example. can give. In particular, those having an aromatic polyimide skeleton are preferable because they have excellent heat resistance, solvent resistance, and toughness. Specific examples thereof include polyether sulfone, polysulfone, polyimide, polyether imide, and polyimide having a phenyltrimethylindane structure.

As a method for synthesizing an aromatic polyimide suitable as a thermoplastic resin component, any method known in the industry can be used. Typically, a tetracarboxylic dianhydride and a diamino compound are reacted. Synthesized by that. Preferable examples of tetracarboxylic acid dianhydride are pyromellitic dianhydride, 3, 3 ', 4, 4'-benzofluoroethylene carboxylic acid dianhydride, 3, 3', 4, 4'- Biphenyl tetracarboxylic dianhydride, 3, 3 ', 4, 4'-diphenyl ether tetracarboxylic dianhydride, 3, 3', 4, 4, 1 diphenyl sulfone tetracarboxylic dianhydride Aromatic tetracarboxylic acid dianhydrides such as compounds, more preferably 3,3 ', 4, 4'monobiphenyltetracarboxylic carboxylic acid dianhydride, 3, 3', 4, 4, diphenyl ether tetra Aromatic tetracarboxylic dianhydrides such as carboxylic dianhydrides can be mentioned.

Preferred examples of the diamino compound are diaminodiphenylmethane, metaphenylene diamine, paraphenylene diamine, diamino diphenyl ether, diamino diphenyl sulfone, diamino diphenyl disulfide, diamino diphenyl diethane, diamino. Nodiphenyl propane, diamino diphenylene ketone, diamino diphenylhexafluoropropane, bis (aminophenoxy) benzene, bis (aminophenoxy) diphenyl sulfone, bis (aminophenoxy) diphenylpropane, bis (Aminophenoxy) diphenylhexafluropropane, diaminodiphenylfluorene, fluorangeamine, dimethyl-substituted diamine diphenylmethane, diamine Aromatic diamino compounds such as tetramethyl-substituted aminodiphenyl methane, dimethyl-substituted diaminodiphenylmethane, tetraethyl-substituted diaminodiphenylmethane, and dimethyljetyl-substituted diaminodiphenylmethane, etc., More preferably, bis (aminophenoxy) benzene, bis (aminophenoxy) diphenylsulfone, bis (aminophenoxy) diphenylpropane, bis (aminophenoxy) diphenylhexafluoropropane, diaminodiphenylfluorene, diami Dimethyl substitution of nodiphenyl methane, tetramethyl substitution of diamino diphenyl methane, acetyl substitution of diamino diphenyl methane, tetraethyl substitution of diamino diphenyl methane, substitution of diamino diphenyl dimethyl dimethyl. An aromatic diamino compound can be mentioned.

Thermoplastic resin consisting of polyimide skeleton, polyamide skeleton, polyether skeleton, polysulfone skeleton, or polyketone skeleton Having hexafluoropropane skeleton in the molecule means dissolution in uncured thermosetting resin It is preferable because it improves the property and forms an appropriate phase-separated structure after curing. In addition, since the water absorption of the cured resin is remarkably reduced by having the structure, it also has an effect of improving the environment resistance of the cured resin. As the component [B] and the thermoplastic resin in the component [D], use a block copolymer or graft copolymer composed of a chain compatible with the thermosetting resin and a chain incompatible with the thermosetting resin. Are particularly preferable from the viewpoint of compatibility control.

One of the preferred specific examples is to form a chain consisting of a siloxane skeleton that is essentially incompatible with the component [B] and the thermosetting resin in the component [D], and has high toughness and low water absorption. It has a block copolymer or a graft copolymer. Particularly preferably, a portion other than the chain composed of the siloxane skeleton is composed of a polyimide skeleton, a polyamide skeleton, a polyether skeleton, a polysulfone skeleton, or a polyketone skeleton in which the thermosetting resin in the constituent [B] is compatible. Is a block copolymer or a graft copolymer. As the siloxane skeleton, dimethylsiloxane is particularly preferable, but phenylsiloxane and its copolymer are also preferable.

The thermoplastic resin obtained by block-copolymerizing the siloxane skeleton has a small increase in resin viscosity due to its addition when compared with an aromatic thermoplastic resin having the same molecular weight. Therefore, there is little deterioration in workability, and the prepreg using this resin as a matrix resin has excellent tackiness and drapeability. From another point of view, the restriction on the amount of the thermoplastic resin added in the constituent [B] is loose, and a large amount can be introduced into the resin system without impairing the tackiness, which is advantageous for improving the resin toughness. The most preferable block copolymer or graphene copolymer as the thermoplastic resin in the component [B] and the component [D] has a polyimide chain portion.

The thermoplastic resin in the component [B] and the component [D] has a functional group capable of reacting with the thermosetting resin in the component [B] at the end of the thermoplastic resin to further enhance the adhesiveness at the phase interface. Therefore, it is preferable from the viewpoint of solvent resistance and fatigue resistance. Specific examples include those having a functional group such as an amino group, an epoxy group, a hydroxyl group and a carboxyl group at the terminal. In particular, a polyamide having an amino group terminal is preferable.

The amount of the thermoplastic resin in the constituent [B] and the constituent [D] is preferably 5 to 40% by weight based on all the components in the constituent [B] and the constituent [D]. If it is less than this, the toughness improving effect is small, and if it is more than this, the workability is significantly reduced. It is more preferably 8 to 30% by weight.

Here, the thermoplastic resin component in the constituent element [B] may be previously dissolved in the uncured thermosetting resin component, or may be simply dispersed. Alternatively, it may be partially dissolved and partially dispersed. By changing the dissolution / dispersion ratio, the viscosity of the resin can be adjusted, and the tackiness and drapeability of the pre-preparer can be adjusted to a desired degree. Most of the dispersed thermoplastic resin also dissolves in the thermosetting resin component during the molding process, and phase-separates again by the end of curing, contributing to the formation of the appropriate Miku mouth phase separation structure.

The molecular weight of the thermoplastic resin in component [B] and component [D] should be the number average molecular weight when the thermoplastic resin component is previously dissolved in the uncured thermosetting resin component. A range of about 2000 to 20000 is preferred. When the molecular weight is smaller than this, the effect of improving toughness is small, and when the molecular weight is larger than this, the resin viscosity is remarkably increased and the workability is markedly reduced. More preferably in the range of about 2500-10000

The component [C] is a long fiber of a thermoplastic resin, which is distributed near the surface of the pre-preder and arranged randomly. Here, the long fiber means a fiber having a length of 3 cm or more. Randomly arranged means an array in which the same structure is repeated at regular intervals (for example, parallel array of monofilament or multifilament, or regular fabric structure such as woven fabric, knitted fabric and braid). It means not to take.

Such an arrangement can be realized by simple spraying or spraying, and does not require special equipment such as a loom as in the case of making regular fabrics. Alternatively, such an arrangement can be realized by utilizing a long-fiber nonwoven fabric. Long fiber Nonwoven fabrics are superior to woven fabrics and pine in that they can directly obtain fabrics from the resin without making the raw material resin into a filament. Further, because of such a form, the problem that the constituent element [C] invades the constituent element [A] like the parallel arrangement does not occur in the prepreg of the present invention.

The feature of the component [C] of the present invention is that it does not have a regular arrangement, but in order to obtain the desired physical properties, it is desirable that the basis weight of the component [C] is as uniform as possible. ..

In addition, the component [C] is distributed in the vicinity of the surface layer of the pre-preder, but since it does not cover the entire surface, it can be easily impregnated with the matrix resin, and the tackiness and drape of the matrix resin are the pre-preda characteristics. Reflected, it becomes a prepreg with excellent handling. Furthermore, component [C] has the function of holding a certain amount of resin on the surface of the prepreg, so it improves the tackiness itself compared to a normal prepreg, and the change in the tackiness with time is extremely small. Have the effect of

The material of the constituent [C] is a thermoplastic resin. A thermoplastic resin having a bond selected from a carbon-carbon bond, an amide bond, an imide bond, an ester bond, an ether bond, a carbonate bond, a urethane bond, a thioether bond, a sulfone bond, an imidazole bond, and a carbonyl bond in the main chain It is typical. Polyamide, Polycarbonate, Polyacetal, Polyphenylene oxide, Polyphenylene sulfide, Polyacrylate, Polyester, Polyamideimide, Polyimide, Polyetherimide, Polysulfone, Polyethersulfone, Polyetherether Ketons, polyalamides, and polybenzimidazoles are suitable for the non-woven fabric used in the present invention because they have high impact resistance. Among these, polyamides, polyimides, polyamideimides, polyetherimides, polyethersulfones, and polysulfones are suitable for the present invention because they have high toughness and good heat resistance. The toughness of polyamide is particularly excellent, and by using one belonging to amorphous transparent nylon, it can also have heat resistance.

As the constituent [C], it is possible to use a combination of long fibers of a plurality of types of thermoplastic resins, or to use a long fiber obtained by composite spinning of a plurality of types of thermoplastic resins. These methods are preferable because the properties of the composite material can be improved by optimizing the combination of materials.

The component [C] needs to be distributed near the surface layer in the pre-preder. As a result, when a composite material is made from It forms a zone and the component [C] is localized between the layers, giving a composite material with excellent impact resistance. To be distributed in the vicinity of the surface layer specifically means that 90% or more of the constituent element [C] is present in the part from the surface of the pre-preder to 30% of the pre-preder thickness. It is more preferable that 90% or more of the constituent element [C] is present in the region from the surface of the prepreg to 20% of the prepreg thickness, because the effect of the present invention is more remarkably exhibited.

If the above conditions are not satisfied and a large amount of component [C] exists deep inside the layer beyond the vicinity of the surface layer, the energy absorption between layers becomes insufficient and the impact resistance and interlaminar toughness of the composite material are reduced. The improvement effect becomes small, and the arrangement of the reinforcing fibers is disturbed, and the fraction of the matrix resin in the vicinity of the reinforcing fibers is reduced, so that the strength and heat resistance may be impaired.

The distribution of component [C] in the prepreg is optimal as long as it is similarly localized on both sides of the prepreg, as it is possible to obtain a composite material by freely laminating the prepreg on both sides. is there. However, even in a pre-preder in which the constituent elements [C] have the same distribution on only one side of the pre-preder, the same effect can be obtained if the constituent elements [c] are always placed between the pre-preders when stacking the pre-preders. Also, such a pre-preder is included in the present invention.

The distribution of component [C] in the prepreg can be evaluated as follows.

First, the prepreg is sandwiched between the two smooth support plates and brought into close contact, and the temperature is gradually raised to cure over a long period of time. At this time, the important thing is to gel at a temperature as low as possible. If the temperature is suddenly raised before gelation occurs, the resin in the prepreg will flow, making it impossible to accurately evaluate the distribution state in the prepreg. After gelation, the temperature is gradually raised over a further period of time to cure the prepreg. Cut the hardened pre-preder and enlarge its cross section by a factor of 200 or more to take a photograph of 200 mm x 200 mm or more. When it is difficult to distinguish the constituent [B] from the constituent [C], one of them is selectively stained and observed. Use either a light microscope or an electron microscope, whichever is suitable.

First, the average thickness of the pre-preder is obtained using this photograph of the cross section. The average thickness of the prepredder should be measured on at least 5 places on the photograph and the average should be taken. Next, draw a line parallel to the plane direction of the prepreg from the surface that was in contact with both support plates at a depth of 30% of the thickness of the prepreg. The area of the component [C] existing between the surface that was in contact with the support plate and the parallel line of 30% was quantified on both sides of the pre-preder. By quantifying the total area of the component [C] existing over the entire thickness of the leg and taking the ratio, the ratio of the component [C] existing within the depth of 30% from the surface of the pre-preder is calculated. Area quantification can also be performed by a gravimetric method or image processing using an image analyzer. In order to eliminate the effect of partial distribution variation, this evaluation is performed over the entire width of the obtained photograph, and the same evaluation is performed for five or more arbitrarily selected photographs, and the average is taken.

It is preferable that the elastic modulus and the yield strength of the material of the component [C] be lower than the elastic modulus and the yield strength of the resin cured product of the component [B] in order to improve the impact resistance of the composite material. However, on the other hand, when the elastic modulus of the material of the constituent element [C] is as low as that of the elastomer, it is likely to be deformed due to changes in conditions such as pressure, temperature or temperature rising rate during molding of the composite material, and the thickness between the laminated plate layers is It tends to fluctuate and change with changes in molding conditions, resulting in unstable physical properties of the composite material. Therefore, it is preferable that the bending elastic modulus of the material of the constituent element [C] in the bulk is in the range of 80 to 400 kg / mm ² in order to obtain stable high toughness that is insensitive to changes in molding conditions. Further, it is also preferable that the tensile elastic modulus when the constituent [C] is in a fibrous state is in the range of 40 to 5000 kg / mm ² for the same reason as above.

The suitable amount of the constituent [C] is in the range of 2 to 30% by weight based on the total amount of the constituent [B] and the constituent [C] in the prepreader or the composite material. If the amount is less than 2% by weight, almost no effect is exhibited, and if it exceeds 30% by weight, the tackiness and drapeability of the prepreg are significantly reduced.

Especially when the rigidity of the constituent element [B] is utilized to develop the compressive strength of the composite material, and the constituent element [C] having high fracture elongation and high toughness is used to increase the toughness between layers of the composite material. Is rather preferable to be in a small range of 2 to 20% by weight, and more preferably 4 to 13% by weight.

The following method can be used as a method of manufacturing the prepreader having the above-described configuration.

[Method 1]

The component [C] is impregnated with the component [B] on the surface of the component [A], and the component [C] is randomly arranged in a plane to form a pre-preder. If this is left as it is, the constituent element [C] will remain exposed on the surface of the pre-preder, and the tackiness will be inadequate. Therefore, after spraying, heating and pressurizing using a heat nozzle, etc., the constituent element [C] Impregnation with [B] is desirable. As a modification of this method, the constituent [A] is impregnated with the constituent [B], but the constituent [C] is randomly arranged on the surface and then applied on a release paper. The element [B] may be attached and heat-pressed for impregnation. In this case, it is also preferable that the constituent [B] to be impregnated in the constituent [A] and the constituent [B] to be applied onto the release paper have different compositions. In particular, if the component [B] to be applied on the release paper or the like is one that has a higher adhesiveness than the component [B] to be impregnated in the component [A], the tackiness of the prepreder can be improved. Yes, it is preferable.

[Method 2]

By applying it to a support such as release paper, the component [C] is randomly arranged in a plane on the surface of the component [B] molded into a film, and laminated with the component [A]. The prepreg is formed by heating and pressing.

As a modification of this method, a method in which the constituent [A] is partially impregnated with the constituent [B] in advance and the same operation is performed can also be used.

[Method 3]

The component [C] is randomly arranged in a plane on the component [A], and then the component [B] is impregnated to form a pre-preder. This method is particularly suitable when [A] has shape-retaining properties such as woven fabric.

In the method of randomly arranging the constituent elements [C] on the plane in the above three methods, first, the thermoplastic resin is spun in advance to obtain a monofilament or a multifilament, and Examples of such methods include spraying the target directly on the target using pressurized air, spraying it through a swinging guide, or hitting the shock plate once and then spraying it after diffusion. In this method, in principle, any spinnable resin can be used as the constituent [C] material. In addition, there is no limit for reducing the basis weight.

It is also possible to arrange the fibers discharged from the die directly and randomly on a plane. In this case, it is possible to apply a method in which fibers discharged from an ordinary spinneret are stretched using a pressurized air flow and sprayed on an object, and a method in which unstretched fibers are sprayed using a melt blow spinneret. These methods are suitable for resins having good spinnability.

In these methods, instead of directly spraying the long fibers onto the target, it is also possible to spray them once on a collector such as a wire mesh and then transfer them onto the target surface. In addition, a long-fiber nonwoven fabric of the constituent element [C] can be prepared in advance by the spunbond method or the melt blow method, etc. Is.

[Method 4]

The pre-preder is formed by laminating the constituent [C] non-woven fabric on the constituent [A] impregnated with the constituent [B]. In this case, if it is left as it is, the constituent element [C] is exposed on the surface of the pre-preder, so the tackiness may become insufficient. Therefore, after bonding, heat and pressure using a heat roller etc. It is desirable to impregnate C] with component [B].

As a modification of this method, the non-woven fabric of the constituent [C] may be impregnated with the constituent [B] in advance. In this case, it is also preferable that the constituent [B] to be impregnated in the constituent [A] and the constituent [B] to be impregnated in the nonwoven fabric of the constituent [C] have different compositions. In particular, if the constituent [B] of the constituent [C] that is impregnated into the nonwoven fabric is one that has a stronger adhesiveness than the constituent [B] that is impregnated into the constituent [A], the tackiness of the prepreg is improved. It is possible and preferable.

[Method 5]

Applying component [B], non-woven fabric of component [C], and component [A], which have been molded into a film by applying them to a support such as release paper, in any order or at the same time in any order and heat and press To form a pre-preder. In this case, the superposition positional relationship is such that the nonwoven fabric of component [C] is sandwiched between the component [A] and the component [B] formed into a film shape, and the nonwoven fabric of component [C] is It is preferable that the component [B] is easily impregnated in the above.

Specifically, the nonwoven fabric of the constituent element [C] is stacked from both sides of the constituent element [A], and then the constituent element [B] formed into a film shape is supplied from both sides of the non-woven fabric and stacked, and the heat roll or the like is laminated. First, a method of heating and pressing with a means to form a pre-preder, and a non-woven fabric of the constituent element [C] bonded to the surface of the constituent element [B] formed into a film pattern are prepared, and this is made into the constituent element [A]. A preferred method is to stack the constituent elements [C] on both sides so that they are on the inner side, and heat and pressurize them by means of a heat roll or the like to form a pre-preder.

Example

Hereinafter, the present invention will be described in more detail with reference to examples.

[Example 1]

The following raw materials were kneaded to prepare a matrix resin composition.

(1) Tetraglycidyl diaminodiphenyl ester (E LM434, manufactured by Sumitomo Chemical Co., Ltd.) 60 parts by weight

(2) Bisphenol A type epoxy resin

(Epikoto 828, manufactured by Yuka Seki Epoxy Co., Ltd.) 20 parts by weight

(3) Trifunctional aminophenol epoxy resin

(E LM100, manufactured by Sumitomo Chemical Co., Ltd.) 20 parts by weight

(4) 4, 4'-diamminodiphenyl sulfone

(Sumikiure S, manufactured by Sumitomo Chemical Co., Ltd.) 47.3 parts by weight

(5) Polyether sulfone

(PES 5003 P, manufactured by Mitsui Toatsu Chemicals, Inc. 16 parts by weight) A sample obtained by impregnating carbon fiber (T 800 H, manufactured by Toray Co., Ltd.) with this matrix resin was prepared using the drum winding method. The amount of carbon fiber per area was 190 / m ² , and the amount of matrix resin was 90.6 gZm ² .

Nylon 66 fiber (15 denier, 5 filament) was sprayed on one surface of this sample using an aspirator equipped with an impact plate at the tip and compressed air to obtain a prepreder. The basis weight of the fiber was 13. O gZm ² .

Pseudo-isotropic structure (+ 45 ° 0 ° Z — 45 ° Z90 °) This prepreder was laminated in 24 layers for ₃ s, and in the autoclave, the temperature was 180 ° C and the pressure was 6 kg / cm ² , and 2 Molded in time. The obtained cured plate was cut into a length of 15 mm and a width of 10 mm to obtain a test piece. After subjecting the center of this test piece to a falling weight impact of 1500 inch-pound Z inch, the compressive strength after impact was measured according to ASTM D 695, and it was 34.0 kg / mm ".

[Example 2]

A sample in which the same matrix resin as in Example 1 was impregnated with carbon fiber (T 800 H, manufactured by Toray Industries, Inc.) was prepared using the drum winding method. The amount of carbon fiber per unit area was 190 gZm ² , and the amount of matrix resin was 90.6 gZm ^2.

The surface of one side of this sample was sprayed with polyetherimide (Ultem 1010, GE Plastics) fibers (13 denier, 1 filament) using an aspirator equipped with an impact plate at the tip and compressed air. I got prepreda. The basis weight of the fiber was 13.0 g / m ² .

A hardened plate was prepared in the same manner as in Example 1 using this pre-preder, and the compression strength after falling weight impact was measured to be 35.8 kg / ImI m ² .

6 [Example 3]

A sample in which the same matrix resin as in Example 1 was impregnated in carbon fiber (T 800 H, manufactured by Toray Industries, Inc.) was prepared by the drum winding method. The amount of carbon fiber per unit area was 190 g / m ² , and the amount of matrix resin was 90.6 gZn ^ o

On one surface of this sample, nylon 12 fibers discharged from a mouthpiece with an orifice were drawn and blown using aspirator with an impact plate at the tip and compressed air to obtain a prepreg. The basis weight of the fiber was 13.0 g Zm ² .

A hardened plate was prepared from this pre-preder in the same manner as in Example 1, and the compressive strength after impact with a falling weight was measured and found to be 36.1 kgZmm ² .

[Comparative Example 1]

Using a drum winding method, a prepreder containing no thermoplastic resin fiber in which the same matrix resin as in Example 1 was impregnated with carbon fiber (T 800 H, manufactured by Toray Industries, Inc.) was prepared. The amount of carbon fiber per unit area was 190 g / m ² , and the amount of matrix resin was 103.6 gZm ² .

A hardened plate was prepared from this prepreg in the same manner as in Example 1, and the compression strength after impact with a falling weight was measured to be 19.7 kg / mm ² .

[Example 4]

The same matrix resin composition as in Example 1 was coated on release paper using a reverse roll coater. The coating amount was 45. 32 ".

Nylon 66 fibers (15 denier, 5 filaments) were sprayed onto the surface of this resin film using an aspirator equipped with an impact plate at the tip and compressed air. The basis weight of nylon 6 6 fiber was 6. S gZm ² .

Fix the resin film sprinkled with NAIKUN 66 fiber on the drum winder, wrap the carbon fiber (T 800 H, manufactured by Toray Co., Ltd.), and then wrap another resin film on which nylon 66 is sprayed. It was affixed to, and impregnated under pressure to obtain a prepreder. The amount of carbon fiber per unit area was 190 g / m ² .

A hardened plate was prepared from this pre-preder in the same manner as in Example 1, and the compression strength after impact with a falling weight was measured to be 34.4 kg / mm ² .

[Example 5]

The same matrix resin composition as in Example 1 was applied on a release paper using a reverse mouth coater. The coating amount was 45.3 gZm ² .

-11- On the surface of this resin film, the fiber of grillamide TR-55 (polyamide made by EMS ER WE RK E Co.) discharged from a die with one orifice was compressed, and compressed with an aspire with an impact plate at the tip. It was stretched and blown with air. The basis weight of the fiber was 6.5 g / m ² .

Darylamide TR-5 5 Fiber resin is fixed on a drum winder, carbon fiber (T 800 H, manufactured by Toray Industries, Inc.) is wrapped around it, and then Grylamide TR-5 5 Another resin film sprayed with the above fibers was attached to this and impregnated under pressure to obtain a prepreder. The amount of carbon fiber per unit area was 190 g / m ² .

A hardened plate was prepared from this pre-preder in the same manner as in Example 1, and the compression strength after impact with a falling weight was measured and found to be 33.7 kgZmm ² .

[Example 6]

A carbon fiber woven fabric (a plain weave of carbon fiber T 800 H manufactured by Toray Industries, Inc. with a fiber basis weight of 196 g / m ") is attached to one end of nylon 6 6 fiber (15 denier, 5 filament). It was sprayed with a striking plate equipped with a striking plate and compressed air.The unit weight of nylon 6 6 fiber was 16.O gZm ^2. It was impregnated with the same matrix resin as in Example 1. A prepreg was obtained.The amount of resin per unit area was 130 g / m ^2. With respect to this prepreg, a cured plate was prepared in the same manner as in Example 1, and the compression strength after impact with a falling weight was measured. The measured value was 29.4 kg mm ² .

[Example 7]

Fiber of grilled amide TR-55 (polyamide made by EM S ER WE RK E) discharged from a mouthpiece provided with one orifice was used by using aspire overnight with a shock plate on the wire mesh and compressed air. It was stretched and sprayed for repair. The fiber sheet repaired on the wire mesh was heat-bonded using a heating press machine, and a nonwoven fabric of grill amid TR-55 was prepared. The fabric weight was 6.5 gZn ^.

A sample obtained by impregnating carbon fiber (T 800 H, manufactured by Toray Industries, Inc.) with the same matrix resin as in Example 1 was prepared by the drum winding method. -Carbon fibers per unit ^{area, 1 9 0 g / m 2} , the amount of the matrix resin, on both surfaces of the sample which was a 9 0. 6 g / m ^2, attached to Guriruami de TR- 5 5 of the nonwoven fabric Then, a pre-preder was prepared.

A hardened plate was prepared from this pre-preder by the same method as in Example 1 and the falling weight impact The subsequent compressive strength was measured and found to be 34. OkgZmm ² .

[Example 8]

Nylon 6 fibers discharged from a mouthpiece provided with one orifice were drawn and dispersed using an aspire overnight equipped with an impact plate at the tip of the wire mesh and compressed air, and collected. The fiber sheet collected on the wire mesh was heat-bonded using a heat press machine to produce a nylon 6 non-woven fabric. The basis weight of the fiber was 6.5 gZn ^.

A sample obtained by impregnating carbon fiber (T 800 H, manufactured by Toray Industries, Inc.) with the same matrix resin as in Example 1 was prepared using the drum winding method. The amount of carbon fiber per unit area was 190 g / m ² , and the amount of matrix resin was 90.6 g / m ² . Nylon 6 non-woven fabric was attached to both sides of this sample to prepare a prepreder. A hardened plate was prepared from this pre-preder in the same manner as in Example 1, and the compression strength after impact with a falling weight was measured and found to be 3 3. lk gZmm ² .

[Example 9]

The same matrix resin composition as in Example 1 was coated on release paper using a revers roll coater. The coating amount was 45.3 g / m ² .

Onto this resin film, the same non-woven fabric of GRILLAMIDE TR-55 used in Example 7 was attached and fixed by pressing with a calendar roll. Then, on both sides of the carbon fibers (T 800 H, manufactured by Toray Industries, Inc.) aligned in one direction, lay a resin film with a non-woven fabric inside so that the non-woven fabric is on the inside, and apply heat and pressure using a heat roll. And impregnated to obtain a pre-preder. The amount of carbon fiber per unit area was 270 g / m '. A hardened plate was prepared in the same manner as in Example 1 with respect to this pre-preder, and the compression strength after falling weight impact was measured. It was .3 k gZmm ² .

[Example 10]

The same matrix resin composition as in Example 1 was applied on a release paper using a reverse roll roll. The coating weight was 45.3 g / m ² .

The same nylon 6 non-woven fabric used in Example 8 was stuck on this resin film, and was pressed and fixed with a calendar roll. Then, on both sides of the carbon fiber (T 800 H, manufactured by Toray Industries, Inc.) aligned in one direction, the resin film with the non-woven fabric attached was placed so that the non-woven fabric was on the inside, and the heat roll was applied. The prepreg was obtained by heating and pressurizing and impregnating. The amount of carbon fiber per unit area was 190 gZm ² . For this prepreg, a hardened plate was prepared in the same manner as in Example 1, and the compression strength after falling weight impact The degree was measured to be 33.6 k gZmm ² .

[Example 1 1]

The core-sheath composite spinneret is made of polyethylene terephthalate from the core and nylon 6 is discharged from the sheath so that the core-sheath ratio is 1: 1. It was stretched with compressed air, scattered, and collected. The fiber sheet collected on the wire mesh was heat-bonded using a heating press machine to produce a nonwoven fabric. The basis weight of the fiber was 6.5 g / m ^Z.

The same matrix resin composition as in Example 1 was applied onto a release paper using a revers roll coat. The applied amount was 45.3 g / n ^.

The above-mentioned non-woven fabric was pasted on this resin film and fixed by pressing with a calendar roll. Then, on both sides of unidirectionally aligned carbon fibers (T 800 H, manufactured by Toray Industries, Inc.), overlay the resin film with the non-woven fabric attached so that the non-woven fabric is on the inside, and heat with a heat roll. It was pressurized and impregnated to obtain a pre-preder. The amount of carbon fiber per unit area was 190 gm ² .

A hardened plate was prepared from this pre-preder by the same method as in Example 1, and the compressive strength after impact with a falling weight was measured and found to be 33.8 kgZmni ² .

[Example 1 2]

(1) Synthesis of reactive poly (oligo sesame)

In a 300 m 1 separable flask equipped with a nitrogen inlet, a thermometer, a stirrer and a dehydration trap, 392 g (0.91 mol) of bis [4- (3-aminophenoxy) was added under nitrogen substitution. Phenyl] sulfone (B AP S—M), 39 g (0. llmol) 9, 9'-bis (4-aminophenyl) fluorene (F DA), 147 g (0, llmol) NH ₂ equivalent 650 Amino-terminated dimethyl siloxane (BY-16-853 available from Toray Silicone Co., Ltd.) was dissolved in 200 Om 1 of N-methyl-2-pyrrolidone (NMP) with stirring. To this, 300 g (1.02 mol) of solid biphenyltetracambonic acid dianhydride was added little by little, and the mixture was stirred at room temperature for 3 hours, then heated to 120 ° C and stirred for 2 hours. After returning the flask to room temperature and adding 50 ml of triethylamine and 50 ml of toluene, the temperature was raised again and azeotropic dehydration was performed at 160 ° C to obtain about 3 Om 1 of water. After cooling the reaction mixture, it was diluted with twice the volume of NMP and slowly poured into 20 I of acetone to precipitate the amine-terminated siloxane polyimidoligoma as a solid product. Then, the precipitate was vacuum dried at 200 ° C. The number average molecular weight (Mn) of this oligomer was measured by gel permeation chromatography using a dimethylformamide (DMF) solvent. It was 5,500 in terms of ethylene glycol (PEG). The glass transition point was 223 ° C according to the differential thermal analyzer (DSC). In addition, the introduction of siloxane skeleton and the fact that it was an amine terminal could be confirmed from NMR spectrum and IR spectrum.

(2) Resin preparation of constituent B and measurement of resin physical properties

20 parts of the siloxane polyimide oligomer prepared in (1) was added to 0, 0 to 1 part of diarylbisphenol A 41, and heated at 140 ° C for 2 hours. 39 parts of diphenylmethane bismaleimide was uniformly mixed and dissolved therein. After vacuum degassing by connecting a vacuum pump to the container, the contents were poured into a mold that had been preheated to 120 ° C and subjected to mold release treatment. The resin was cured in an oven at 180 ° C for 2 hours to prepare a 3 mm thick resin-hardened plate. Further, this cured plate was subjected to a blast cure at 200 ° C for 2 hours and at 250 ° C for 6 hours. The T g of the obtained cured resin was 295 ° C. The fracture strain energy release rate G _ie was 450 J / ¹ and the flexural modulus was 380 kg / mm ² . When a resin plate of 60 x 10 x 2 mm was boiled for 20 hours, its water absorption rate was 2.0%.

The polished surface of the cured resin was stained with osmium tetroxide, and observation of the backscattered electron image with a scanning electron microscope revealed that a microphase-separated structure in which the phase mainly composed of the oligomer was a continuous phase was formed.

(3) Preparation of pre-preda and composite materials and measurement of physical properties

First, 20 parts of the siloxane polyimido oligomer synthesized in (1) was dissolved in 1 part of 0,0'-diallyl bisphenol A 41, and then 39 parts of diphenyl methane bismaleimide was uniformly mixed in a kneader.

This resin composition was coated on a release paper on which a silicone release agent was thinly applied in advance with a constant thickness to obtain a resin film having a basis weight of 47 gZm ² .

A unit weight of 190 g / m ² carbon fiber ("Torayca" T800 H Toray Co., Ltd.) is aligned in one direction, and then a unit weight of 5 gZm ² is made from nylon 6 above and below the carbon fiber. The above non-woven fabrics were laid one on top of the other, and the above resin films were pressed from above and below to impregnate the resin into the fiber to obtain a prepreder. This prepredder was good in dawnability and drapeability. The pre-preder was sandwiched between two smooth Teflon plates, gradually heated to 180 ° C over 2 weeks to be cured, and the cross section was observed and micrographs were taken. When the amount of non-woven fabric existing in the range from the prepreg surface to the depth of 30% of the prepreg was evaluated, the value was 100%, and the non-woven fabric was well localized on the prepreg surface. I was there.

When this cured prepreg was dyed with osmium tetroxide and the backscattered electron image was observed with a scanning electron microscope, the matrix resin had a microphase-separated structure in which the oligomeric phase was a continuous phase.

Pre-preders were laminated in 24 layers in a pseudo-isotropic configuration ((+ 45 ° / 0 ° / -45 ° / 90 °) _3S ), using a normal vacuum bag autoclave molding method, under pressure of 6 k g Zc 1 The temperature was raised from 25 to 180 ° C at a heating rate of 0.5 ° C / min, and a cured plate was obtained by thermoforming at 180 ° C x 2 hours. Furthermore, this cured plate was subjected to boss cure at 200 ° C for 2 hours and at 250 ° C for 6 hours. The fiber volume fraction was 55.4 V o 1% and the resin weight fraction was 35.8 wt%. After molding, observing the cross section with an optical microscope, it was confirmed that all the non-woven fabrics were completely present in the interlayer frame area of the cured plate.

When the polished surface of the cured plate was stained with osmium tetroxide and the backscattered electron image was observed with a scanning electron microscope, a microphase-separated structure in which a continuous phase containing an imide oligomer as a main component was formed was observed.

The compressive strength of this cured plate after impact with falling weight was measured to be 33.1 kg / mm ^Z. Industrial applicability

The prepreg of the present invention has long fibers of thermoplastic resin having no regular arrangement in the vicinity of the surface layer, so that tackiness and drape, high elastic modulus when heat-molded into a composite material, and heat resistance It provides a composite material that has excellent impact resistance and interlaminar toughness while maintaining its properties. Further, such a prepreder is easy to manufacture, has a high degree of freedom in materials, and is industrially significant.

Claims

The scope of the claims

1. A pre-preda consisting of the following constituents [A], [B], and [C], in which constituent [C] is distributed near the surface of one or both surfaces, and constituent [C] is randomly arranged.

[A]: Reinforcing fiber consisting of long fibers

CB]: Matrix resin

[C]: Long filament of thermoplastic resin

2. The thermoplastic resin of [C] is polyamide, polycarbonate, polyacetal, polyphenylene oxide, polyphenylene sulfide, polyarylate, polyester, polyamide imide, polyimide, polyether imide, polysulfone. The pre-preda of claim 1 which is one or more selected from the group consisting of: polyether tersulfone, polyether ether ketone, polyaramid, and polybenzimidazole.

3. A pre-predeer for claim 1 in which the thermoplastic resin of [C] has a flexural modulus of 80 to 400 kg / mm ² .

4. The pre-preder of Claim 1 wherein the tensile modulus of the long fibers of the thermoplastic resin of [C] is 40 to 500 kg / mm ² .

5. The pre-predator according to claims 1 to 4, wherein the matrix resin of [B] is a thermosetting resin.

6. Thermosetting resin includes epoxy resin, maleimide resin, bismaleimide triazine resin, thermosetting polyimide resin having terminal reactive group, acetylene-terminated resin, nadic acid-terminated resin, cyan 1 selected from the group consisting of acid ester-terminated resin, vinyl-terminated resin, aryl-terminated resin phenol resin, resorcinol resin, unsaturated polyester resin, diaryl phthalate resin, urea resin and melamine resin 1 This is the pre-preparer for claim 5.

7. The prepredder according to claim 1, which is a matrix resin composition in which the component [B] undergoes phase separation in the process of heating from 10 ° C to 250 ° C.

8. The pre-preder of claim 7, wherein the component [B] is a thermosetting resin composition in which a thermosetting resin-soluble thermoplastic resin is mixed or dissolved.

9. The pre-predeer of claim 8 in which the thermosetting resin-soluble thermoplastic resin in component [B] is a thermoplastic resin selected from polyethersulfone, polysulfone, polyimide, and polyetherimide.

1 0. The prepreg according to claim 8, wherein the thermosetting resin-soluble thermoplastic resin in the component [B] is a reactive polyimide.

1 1. The pre-predeer of Claim 10 in which the reactive polyimide in the component [B] is a block-polymerized siloxane chain.

1 2. A pre-preder composed of a reinforced fiber layer in which reinforcing fibers are impregnated with a matrix resin, and a nonwoven fabric layer formed by impregnating a nonwoven fabric made of a thermoplastic resin with a matrix resin is laminated on one or both sides.

1 3. The weight B (g / m ² ) of the matrix resin and the weight C (g / m ') of the non-woven fabric made of thermoplastic fibers per unit area of the pre-preder have a relationship satisfying the following formula. Pre-preda of claims 1 and 2 characterized by

2 ≤ C x l 0 0 ≤ 30

1 4. A method of manufacturing a pre-preder characterized by impregnating the constituent element [A] with the constituent element [B] and randomly arranging the constituent element [C] from one side or both sides of the constituent o.

[A]: Reinforcing fiber consisting of long fibers

[B]: Matrix resin

[C]: Long filament of thermoplastic resin

15. A method for manufacturing a pre-preder, which comprises randomly arranging the constituent elements [C] in a plane from one side of the film constituent elements [B], and then laminating the constituent elements [A] on one side or both sides.

1 6. The components [C] are randomly arranged in a plane from one side of the film-shaped component [B], and then the one side or both sides of the component [A] impregnated with the component [B] are attached. A method of manufacturing a pre-preder characterized by the above.

1 7. A method for producing a pre-preder of claim 16 in which the composition of the film-like constituent [B] and the constituent [B] to be impregnated are different.

1 8. A method for manufacturing a prepredder characterized by randomly arranging the component [C] on one side or both sides of the component [A] in a plane and then impregnating the component [B].

1 9. A method for manufacturing a prepredder characterized by impregnating the constituent element [A] with the constituent element [B], and laminating a long-fiber nonwoven fabric composed of the constituent element [C] on one or both sides thereof.

20. Component [A] is impregnated with component [B], and one or both surfaces of the component [B] are impregnated or laminated with a long-fiber nonwoven fabric composed of component [C]. A method of manufacturing a pre-preder characterized by the above.

21. The method for manufacturing the pre-preder according to claim 20, wherein the composition of the constituent [B] to be impregnated in the constituent [A] and the constituent [B] to be impregnated or bonded to the long-fiber nonwoven fabric composed of the constituent [C] are different.

22. A method for manufacturing a prepredder by laminating a nonwoven fabric composed of a film-like constituent [B] and a constituent [C] and a constituent [A] in any order or simultaneously in any order.

23. The manufacturing method according to claim 22, wherein the non-woven fabric of the constituent element [C] is sandwiched between the constituent element [A] and the constituent element [B] formed into a film shape in the positional relationship of superposition.

24. Overlay the non-woven fabric of component [C] from one side or both sides of component [A], and then supply the component [B] formed into a film form from one side or both sides and superimpose them. 23. The manufacturing method according to claim 22.

25. First, the one in which the non-woven fabric of the constituent [C] is laminated on the surface of the constituent [B] formed into a film is prepared, and this is formed on one side or both sides of the constituent [A]. 23. The manufacturing method according to claim 22, wherein the layers are laminated and attached so that the inside is on the inside.

26. A composite material composed of the following constituents [A], [D], and [C], in which the constituents [C] are randomly arranged in a plane between the laminated layers.

[A]: Reinforcing fiber consisting of long fibers

[D]: Matrix resin cured product

[C]: Long filament of thermoplastic resin

27. A composite material of claim 26 in which the constituent [D] has a phase separated structure.

28. The composite material according to claim 27, wherein the constituent element [D] has a structure in which the thermosetting resin-based phase and the thermoplastic resin-based phase are phase-separated.

29. Composite material according to claim 28, characterized in that the thermoplastic resin-based phase in component [D] is based on polyimide.

30. The composite material according to claim 29, characterized in that the polyimide in the constituent element [D] is a polyimide containing a gay element.

31. Thermosetting resin in component [D] is epoxy resin, maleimide resin, bismaleimide * triazine resin, thermosetting polyimide resin having a terminal reactive group, acetylene terminated resin, Nagic Resin with acid end, resin with cyanate end, resin with vinyl end, resin with aryl end, phenol resin, resorcinol resin, unsaturated polyester resin, diaryl phthalate resin, urea resin, melamine resin Claim 2 characterized by being one or more selected from the group 2 7 to 30 composite material _c