WO2013129540A1 - Composite material for molding a fiber-reinforced plastic and fiber-reinforced plastic molded bodies - Google Patents

Abstract

The purpose of the present invention is to provide a composite material for molding a fiber-reinforced plastic that enables fiber-reinforced plastic molded bodies to be continuously produced in an efficient manner by heat and pressure molding, said fiber-reinforced plastic molded bodies having high heat resistance, flame resistance and low smoke properties. The composite material for molding a fiber-reinforced plastic is characterized by containing: a reinforced fiber component comprising at least one type of inorganic fiber selected from a glass fiber and a carbon fiber; and a matrix resin component comprising thermoplastic super-engineered plastic fibers having a limiting oxygen index of not less than 25, a fiber diameter of not more than 30 μm and not more than four times the fiber diameter of the reinforced fibers. The composite material for molding a fiber-reinforced plastic is further characterized by comprising a nonwoven sheet containing a reinforced fiber component comprising inorganic fibers, a matrix resin fiber component comprising polyetherimide fibers, and at least one type of binder component, said fiber components in the surface layer of the nonwoven sheet being bonded by the binder component, which exists locally in a paddle-like film form mainly at the intersection points of the fiber components.

Description

Fiber reinforced plastic molding composite and fiber reinforced plastic molding

The present invention relates to a fiber reinforced plastic molding composite material, which is a precursor of a fiber reinforced plastic molding using thermoplastic fibers as a matrix resin, and a fiber reinforced plastic molding obtained by heating and pressing the composite material. In particular, the matrix resin uses thermoplastic resin fibers called heat engineering and high flame retardancy, so-called super engineering plastics, and the molded product has high flame retardancy and strength and can be molded in a short time. The present invention relates to a fiber reinforced plastic molding composite material and a fiber reinforced plastic molded body obtained by heating and pressing the composite material. Furthermore, fiber reinforced plastic molding composite material that uses polyetherimide resin fibers as a matrix resin, is heat resistant and flame retardant and can be molded in a short time, and heat-press molding it, The present invention relates to a fiber reinforced plastic molded article having high flame retardancy and strength and generating little smoke even when burned.

As a lightweight and high-strength composite material, resin moldings reinforced with carbon fiber, glass fiber or other reinforcing fibers are already used in various fields such as sports, leisure goods, and aircraft materials. As the resin used as a matrix in these carbon fiber reinforced resin molded products, epoxy resins, unsaturated polyester resins, and sometimes thermosetting resins such as phenol resins are often used. However, in the case of these thermosetting resins, the impact resistance of the fiber reinforced resin molding is inferior, and when the resin is impregnated into the fiber to make a prepreg, refrigeration storage is necessary, and the pot life is limited. There is a difficulty that long-term storage is not possible.

Furthermore, the thermosetting resin needs to be cured by a polymerization reaction in a heated state, but since the polymerization reaction takes time, there is a problem that the heat molding time becomes long and the productivity is low.

On the other hand, when a thermoplastic resin is used as a matrix resin, the impact resistance of the fiber reinforced resin molded article is excellent, and the storage management of the resin and the fiber reinforced resin composite material in a state before molding processing is easy, and the molding time is short. Therefore, for example, a development study of a fiber reinforced resin molded body made of a fiber reinforced resin composite material using a thermoplastic resin as a matrix resin, such as a polycarbonate resin, a polyester resin, or a polypropylene resin, has been conducted.

In general, when a fiber reinforced plastic molded body is prepared from these resins, the composite material that is a precursor thereof is manufactured by a melting method (hot melt method), a solvent, depending on the type of resin impregnation method for the fiber. Methods, dry powder coating methods, powder suspension methods, resin film impregnation methods (film stacking methods), mixed weaving methods (Commingle), and the like have been proposed (Non-Patent Document 1).

The melting method is a manufacturing method in which a thermoplastic resin is melted by an extruder, continuous fibers are passed through a melting bath, and the resin is impregnated into the inside of the fiber. The solvent method is a resin (mainly amorphous resin) that is a solvent. This is a production method in which a reinforcing fiber is impregnated using a solution dissolved in (1).

The dry powder coating method is a method in which dry powder is adhered to reinforcing fibers and heated in the next step to melt and impregnate the powder. The powder suspension method is a method in which reinforcing fibers are passed through a tank in which resin powder is uniformly dispersed in water or a solvent, the powder is adhered to the reinforcing fibers, and heated in the next step to melt and impregnate the powder.

The resin film impregnation method is a manufacturing method in which a resin film and reinforcing fibers are overlapped and the resin is melted and impregnated by a double belt press or an intermittent press method.

The mixed weaving method (Commingle) is a technique for producing a composite yarn by combining a reinforcing fiber and a thermoplastic resin fiber. The composite yarn is woven (unidirectional, plain weave, braided, multiaxial woven fabric, etc.) to obtain an intermediate material, which is directly passed through a thermoforming process, and a thermoplastic resin fiber is impregnated into the reinforcing fiber to obtain a product.

On the other hand, a technique has been proposed in which a short fiber of a thermoplastic resin and a reinforcing fiber are mixed and dispersed in air or water to form a sheet, and the thermoplastic resin short fiber and the reinforcing fiber are combined (Patent Document 1,). Patent Document 2).

In Patent Document 1, a proposal is made to heat and press-mold a web obtained by uniformly mixing carbon fibers as reinforcing fibers and a thermoplastic fibrous matrix resin in air or water and capturing them on a net. Patent Document 2 discloses a technique for heat-pressing a paper-making substrate obtained by dispersing reinforcing fibers and matrix resin fibers in a dispersion medium, mixing them, and then removing the dispersion medium. ing.

However, a fiber reinforced resin molded article using a thermoplastic resin such as polycarbonate resin, polyester resin, or polypropylene resin as a matrix resin as described above has a thermosetting resin as a matrix resin in terms of heat resistance and flame retardancy. There is a disadvantage that it is inferior to the fiber reinforced resin molded product.

Japanese Patent Publication No.62-1969 JP 2011-157638 A JP 2007-269308 A JP 2006-077342 A

In recent years, thermoplastic resins with excellent heat resistance and chemical resistance have been actively developed, and the above-mentioned drawbacks that have been common knowledge about thermoplastic resins have been remarkably improved. It is coming. Such thermoplastic resins are so-called “super engineering plastics”, which are polyphenylene sulfide (PPS), polyether ether ketone (PEEK), polyamide imide (PAI), polyether imide (PEI). (Non-Patent Document 1).

The above-mentioned thermoplastic resin called “super engineering plastic” is not only excellent in strength but also has a very high flame retardancy, and has a critical oxygen index of 30 or more in a resin block state. There are many. In particular, polyetherimide (hereinafter referred to as PEI) is characterized by a high critical oxygen index of 47 and extremely low smoke generation during combustion. Although various attempts have been made to study composite materials using such super engineering plastics, there are the following problems.

Prepregs manufactured by the melt method (hot melt method), solvent method, dry powder coating method, powder suspension method, resin film impregnation method (film stacking method), and mixed weaving method (Commingle method) are compared with thermosetting prepregs. At present, it is hard, has no drape, has low tack, and is extremely poor in handling (Non-Patent Document 1).

Furthermore, prepregs using super engineering plastics are characterized by a shorter molding time than thermosetting prepregs. However, the melting method (hot melt method), solvent method, dry powder coating method, powder suspension method, resin The prepreg produced by the film impregnation method (film stacking method) has poor air permeability. Therefore, if molding is attempted in a short period of time, bubbles existing between the hot plate for pressing and the sheet cannot be completely removed, and the molten resin is contained in the molten resin. Intrusion tends to cause defects such as poor appearance and defects in strength.

In addition, when a plurality of prepregs are stacked in order to obtain a desired thickness of the molded product after heat and pressure molding, air is easily trapped between the prepregs, and defects are more likely to occur than in the case of a single layer. .

In addition, the woven fabric obtained by the mixed weaving method can give flexibility before forming, but generally has a lower productivity than the method in which short fibers are dispersed in air or water to form a sheet. It has the disadvantage of high cost.

In order to avoid the above drawbacks, in Patent Document 1 and Patent Document 2, carbon fibers that are reinforcing fibers and thermoplastic fibrous matrix resin are uniformly mixed in air or water and captured on a net. A proposal has been made to heat-press the obtained web, and Patent Document 2 obtained by dispersing reinforcing fibers and matrix resin fibers in a dispersion medium, mixing them, and then removing the dispersion medium. Although a technique for heat-pressing a papermaking substrate has been disclosed, such a web or papermaking substrate has a binder as an essential component in order to obtain process strength when moving to a pressing process after mat formation. .

However, a prepreg made of a thermoplastic resin, which is a super engineering plastic with high heat resistance and flame retardancy, is exposed to a high temperature of 300 ° C. or higher during heat and pressure molding, and therefore it is thermally decomposed and vaporized in the molded product. Voids (hereinafter referred to as “voids”) are generated due to the binder, and both appearance and strength are likely to decrease. None of the above-mentioned prior art documents disclose a technique relating to a binder that can withstand the heating and pressing process at a high temperature as described above.

As disclosed in Patent Documents 1 and 2, the binder component that can be generally used in the process of producing a normal web or papermaking substrate has lower flame retardancy than PEI fiber, and does not emit smoke during combustion. Many. Therefore, when a prepreg using such a binder component is subjected to heat and pressure molding, the characteristics of the PEI resin such as heat resistance, flame retardancy, and low heat generation are impaired. Furthermore, at the molding temperature of the PEI resin of 300 ° C. or higher, the binder as described above starts thermal decomposition and emits an odor, which causes a problem that the working environment is deteriorated.

In order to eliminate such drawbacks, Patent Document 3 introduces that a web is made by entwining carbon fibers by a papermaking method, but this method is weak and cannot be industrially produced. Further, Patent Document 4 discloses a method for fixing a fiber or a papermaking substrate between fibers with PEI resin itself.

However, in the case of continuous production by such a method, in order to obtain the required sheet strength during the manufacturing process, it is necessary to heat at a temperature of at least 220 ° C. or higher and at a higher temperature for a certain period of time to maintain normal manufacturing efficiency. There is. In general, the process of industrially continuously producing a sheet from the above-mentioned web or papermaking substrate does not have such a high-temperature heating process, and cannot be manufactured with existing equipment. Even if it has a heating step, the energy efficiency is extremely deteriorated, so that it is practically difficult to industrially continuously produce at the current technical level.

In view of such circumstances, in the present invention, a fiber from which a fiber-reinforced resin molded article having high strength, high heat resistance, and excellent flame retardancy using a thermoplastic resin having high heat resistance and flame retardancy as a matrix resin is obtained. In composite materials for reinforced plastic molding, sufficient strength can be obtained without generating voids even in a very short heating and pressure molding time, the composite material itself is highly productive, and it is easy to handle in the processing process. An object is to provide an excellent fiber-reinforced plastic molding composite material at low cost.

The present invention is also a fiber reinforced plastic molding composite material using PEI fibers as a matrix resin, and can be continuously produced with high production efficiency, has a low odor when processed into a molded body, and is heated and pressed. It is an object of the present invention to provide a composite material for molding fiber-reinforced plastics having features of high heat resistance, flame retardancy, and low smoke generation.

As a result of intensive studies to solve the above-mentioned problems, the present inventors have developed a specific fiber in a composite material for molding a fiber-reinforced plastic using a heat-resistant and flame-retardant thermoplastic resin called a so-called super engineering plastic. By using thermoplastic resin fibers with a diameter as the matrix resin, the heat and pressure molding time is shorter than the conventional fiber reinforced plastic molding composite material using a high heat resistant thermoplastic resin. However, it has been found that the fibers are sufficiently melted and sufficient strength can be obtained.

Furthermore, it is possible to keep the breathability of the fiber reinforced plastic molding composite material higher than a certain value (air easily passes), and no voids are generated even in a short heating and pressing time, and the appearance and strength It was found that a good fiber-reinforced resin molded article can be obtained.

In addition, in order to uniformly mix the reinforcing fibers and the thermoplastic resin fibers and increase the productivity of the fiber-reinforced plastic molding composite material, the chopped strands (short fibers) of the thermoplastic fibers and reinforcing fibers are formed into a sheet shape. However, in this case, as a method for binding the intersections of the short fibers, it is necessary to provide a binder. In this case, when the binder type / mixing ratio / distribution in the composite material has specific conditions, the handling property as a fiber-reinforced plastic molding composite material is good, and the fiber after heat-pressure molding It has been found that the reinforced plastic has no voids and has a good appearance and high strength.

In addition, the flame retardancy and low smoke generation characteristics of PEI are achieved by effectively using a binder that is inferior in flame retardance to PEI resin, generates a lot of smoke, and generates odor at the molding temperature of PEI resin. It can be continuously produced with good manufacturing efficiency without loss, has low odor when processed into a molded product, and has high heat resistance, flame retardancy, and low smoke generation after being heated and pressed. It has been found that a fiber-reinforced plastic molding composite material having characteristics can be obtained.

That is, the present invention includes the following.

(1) Reinforcing fiber component composed of at least one kind of inorganic fiber selected from glass fiber and carbon fiber, a limiting oxygen index of 25 or more, a fiber diameter of 30 μm or less, and 4 times or less of the fiber diameter of the reinforcing fiber A fiber-reinforced plastic molding composite material (stampable sheet) comprising a matrix resin component comprising super engineering plastic fibers.

(2) JAPAN TAPPI Paper Pulp Test Method No. The fiber-reinforced plastic molding composite material (stampable sheet) according to (1), wherein the air permeability defined in 5-2 is 200 seconds or less.

(3) The fiber reinforced plastic according to (1) or (2), wherein the super engineering plastic fiber and the reinforcing fiber are both chopped strands and are formed into a nonwoven fabric sheet by a dry nonwoven fabric method or a wet nonwoven fabric method. Composite material for molding (stampable sheet).

(4) The fiber reinforcement according to any one of (1) to (3), wherein the fiber reinforced plastic molding composite material (stampable sheet) contains a binder component in an amount of up to 10% by mass. Composite material for plastic molding (stampable sheet).

(5) The binder component in the fiber reinforced plastic molding composite material (stampable sheet) is unevenly distributed so that many portions thereof are present on the surface layer portion of the fiber reinforced plastic molding composite material (stampable sheet). (4) The fiber-reinforced plastic molding composite material (stampable sheet) according to (4).

(6) The fiber-reinforced plastic molding composite material (stampable sheet) according to (4) or (5), wherein the binder component is compatible with a matrix resin component made of the super engineering plastic fiber.

(7) The binder component according to any one of (4) to (6), wherein the binder component is applied to the nonwoven fabric sheet by a coating method or an impregnation method as a solution or emulsion containing the binder component. Fiber reinforced plastic molding composite material (stampable sheet).

(8) A method for producing a fiber-reinforced plastic molding composite material (stampable sheet) described in any of (1) to (7) above,
A reinforcing fiber component made of at least one inorganic fiber selected from glass fiber and carbon fiber, a supercritical oxygen index of 25 or more, a fiber diameter of 30 μm or less, and a fiber diameter of the reinforcing fiber of 4 times or less A method for producing a fiber-reinforced plastic molding composite material (stampable sheet), comprising a step of mixing a matrix resin component made of engineering plastic fibers to form a nonwoven fabric sheet.

(9) The fiber reinforced plastic molding composite material (stampable sheet) according to (8), wherein the step of forming the nonwoven fabric sheet is a nonwoven fabric forming step of either a dry nonwoven fabric method or a wet nonwoven fabric method ) Manufacturing method.

(10) The process of forming the said nonwoven fabric sheet forms the nonwoven fabric sheet in which many parts of the binder amount contained in all the nonwoven fabric sheets are unevenly distributed in the surface layer part of the front and back of a nonwoven fabric sheet using a binder containing liquid. The method for producing a fiber-reinforced plastic molding composite material (stampable sheet) according to (8) or (9), comprising the step of:

(11) The step of forming the nonwoven fabric sheet includes a step of heat-treating the nonwoven fabric sheet having a matrix resin component composed of the reinforcing fiber component and the super engineering plastic fiber under conditions in which the super engineering plastic fiber is partially melted. (8) The method for producing a fiber-reinforced plastic molding composite material (stampable sheet) according to any one of (8) to (10).

(12) The fiber reinforced plastic molding composite material (stampable sheet) described in any one of (1) to (7) above is pressed under a condition in which the matrix resin component made of the super engineering plastic fiber melts. A fiber-reinforced plastic molded body formed by heat molding.

(13) A reinforcing fiber component made of inorganic fiber, a matrix resin fiber component made of polyetherimide fiber, and a non-woven sheet containing at least one binder component, and the fiber components in the surface layer portion of the non-woven sheet are A fiber-reinforced plastic molding composite material (stampable sheet) characterized in that it is bonded mainly at the intersection of the fiber components by the binder component localized in the form of a drainage film.

(14) Of the at least one binder component, the binder component that is localized in the form of a scraping film at the intersection of the fiber components in the surface layer portion contains at least one selected from methyl methacrylate and ethyl methacrylate as the monomer component (13) A fiber-reinforced plastic molding composite material (stampable sheet) according to (13).

(15) The at least one binder component contains a particulate or fibrous thermoplastic resin that is compatible with the polyetherimide fiber component in a heat-melted state, (13) or (13) 14) Fiber-reinforced plastic molding composite material (stampable sheet).

(16) The fiber-reinforced plastic molding composite material (stamper) according to (15), wherein the particulate or fibrous thermoplastic resin contains at least one selected from polyester resins and modified polyester resins Bull seat).

(17) The fiber-reinforced plastic molding composite material according to any one of (13) to (16), wherein the total content of the binder component is 0.3% by mass or more and 10% by mass or less. Stampable seat).

(18) a copolymer containing at least one selected from methyl methacrylate and ethyl methacrylate as a monomer component, and at least one fibrous resin selected from a fibrous polyester resin and a fibrous modified polyester resin; The content of the copolymer with respect to the fiber-reinforced plastic molding composite material (stampable sheet) is 0.7 to 4.0% by mass, and the fiber-reinforced composite material for fiber-reinforced plastic molding ( The fiber-reinforced plastic molding composite material (stampable sheet) according to (17), wherein the content is 1.5% by mass to 6% by mass relative to the stampable sheet) and the total content of the binder component is 8% by mass or less ).

(19) The fiber component in the intermediate layer between the surface layers is bonded (melt-bonded) by a particulate or fibrous thermoplastic resin that is compatible with the polyetherimide fiber component in a heated and melted state. The composite material (stampable sheet) for fiber-reinforced plastic molding according to any one of (13) to (18).

(20) A method for producing a fiber-reinforced plastic molding composite material (stampable sheet) according to any one of (13) to (19), comprising a reinforcing fiber component comprising the inorganic fiber and a polyetherimide fiber A non-woven fabric having a matrix resin fiber component is applied with a solution-type or emulsion-type binder solution, and then the non-woven fabric is dried while the non-woven fabric is rapidly heated to transfer the main part of the binder solution to the non-woven fabric surface layer portion. A method for producing a fiber-reinforced plastic molding composite material (stampable sheet), characterized in that the intersections of the fiber components of the surface layer portion of the nonwoven fabric are bonded with a binder localized in the form of a water-scrip film.

(21) The fiber-reinforced plastic molding composite material (stampable sheet) according to any one of (13) to (19) is formed by heating and pressing at a temperature of 250 ° C. or higher and 430 ° C. or lower. , Fiber reinforced plastic molding.

(22) The fiber-reinforced plastic molded article according to (21), wherein the smoke concentration after 20 minutes combustion in a flammable method based on ASTM E662 is 43 DS or less.

(23) The fiber-reinforced plastic molded article according to (21) or (22), which has a limiting oxygen index measured in accordance with JIS K-7102-2 of 40 or more.

A stampable sheet is a member before molding of a fiber-reinforced plastic molded body using a thermoplastic resin as a matrix resin. A member before molding fiber-reinforced plastic with a so-called thermosetting resin is usually called a “prepreg”, and a stampable sheet corresponds to this “prepreg”. In the present invention, the “prepreg” includes a member before molding a fiber reinforced plastic with a thermoplastic resin.

This specification is described in the specification and / or drawings of Japanese Patent Applications Nos. 2012-44141, 2012-93479, 2012-155590 and Japanese Patent Application No. 2012-280652 which are the basis of the priority of the present application. Includes content.

The composite material for molding a fiber-reinforced plastic of the present invention is molded into a fiber-reinforced plastic body that is free from voids and good in strength and appearance by being heated and pressed.

According to the present invention, a sheet of a nonwoven fabric-like structure containing a thermoplastic matrix resin fiber component made of flame retardant PEI fiber and a reinforcing fiber component made of inorganic fiber, which can be industrially continuously produced. It is possible, composite material for fiber-reinforced plastic molding with excellent handling properties that has sufficient interlayer strength even in the process of processing into molded bodies by lamination, heat press, etc., and excellent flame retardancy and low smoke generation A fiber-reinforced plastic molded article is provided.

It is a photograph which shows the state which couple | bonded the intersection of fibers with the waterbrush-like binder. It is a schematic diagram which shows the state which couple | bonded the intersection of fibers with the waterbrush-like binder.

Hereinafter, the present invention will be described in detail.

General reinforcing fibers such as metal fibers, ceramic fibers, glass fibers, and carbon fibers can be widely used as the reinforcing fibers used in the fiber-reinforced plastic molding composite material of the present invention. These inorganic fibers are all preferable in terms of flame retardancy and low smoke generation, and one of them can be used, or a plurality of them can be used in combination. In general, carbon fiber and glass fiber are preferable from the viewpoints of fiber strength and weight, adhesiveness with a thermoplastic resin, and the like.

You can use a sheet of these reinforcing fibers knitted in a cloth (cloth), use a sheet laid in one direction, or shorten the fiber and disperse it in the air before capturing it on a net or the like. It is possible to use a sheet, or a sheet obtained by dispersing in a solvent and then removing the dispersion medium.

The thickness of the reinforcing fiber is not particularly limited, but is preferably 3 μm to 18 μm. If the fiber diameter of the reinforcing fiber is smaller than this, it may be carcinogenic when taken into the human body during the manufacturing process or use, which is not preferable. Further, if the fiber diameter of the reinforcing fiber is larger than this, the uniformity of the mixture with the super engineering plastic fiber is deteriorated, which is not preferable in terms of strength. The fiber length of the reinforcing fiber is preferably about 3 mm to 30 mm. When longer than this, a fiber will not disperse | distribute uniformly but the uniformity of a sheet | seat and the uniformity of a mixing ratio with a reinforced fiber will fall. Moreover, when shorter than this, the molded object strength will fall. The fiber diameter and fiber length may be single, or those having different fiber diameters and fiber lengths may be blended and used.

The thermoplastic resin fiber used in the composite material for molding a fiber-reinforced plastic of the present invention is a fiber made from a heat-resistant and flame-retardant thermoplastic resin called a so-called super engineering plastic. Examples of such thermoplastic resins include polyetheretherketone (PEEK), polyamideimide (PAI), polyphenylene sulfide (PPS), polyetherimide (PEI), polyetherketoneketone (PEKK), etc. It is not limited to this.

It is preferable that the super engineering plastic fiber obtained by fiberizing a resin which is a super engineering plastic used for the fiber-reinforced plastic molding composite of the present invention has a critical oxygen index of 25 or more and a glass transition temperature of 140 ° C. or more in the fiber state. Further, even if the glass transition temperature is lower than this, it is preferable that the resin has a deflection temperature under load of 190 ° C. or higher. Such a super engineering plastic fiber has a very high flame retardance with a critical oxygen index of 30 or more in a state of being melted by heating and pressurizing to form a resin block.

In one embodiment, the thermoplastic resin fiber used in the fiber-reinforced plastic molding composite of the present invention is a PEI fiber obtained by fiberizing a PEI resin. The PEI resin used in this fiber has a critical oxygen index of 40 or more after being melted and processed, and a smoke generation amount of about 30 ds when burned for 20 minutes as measured by the method described in ASTM E-662. It is characterized by low smoke generation.

In the present invention, the “limit oxygen index” represents an oxygen concentration necessary to continue combustion, and is a numerical value measured by a method described in JIS K7201. That is, a critical oxygen index of 20 or less is a numerical value indicating that combustion is performed in normal air.

The composite material for molding fiber reinforced plastics of the present invention is a mixed weaving method in which super engineering plastic fibers that form a matrix by reinforcing fibers and thermoforming are alternately knitted, or super engineering plastic fibers that form a matrix by reinforcing fibers and thermoforming. A method of forming a web by dispersing chopped strands cut to a length in air and trapping them in a net (dry nonwoven fabric method), or dispersing both the chopped strands in a solvent, and then removing the solvent to remove the web Although it can manufacture by methods, such as the method of forming (wet nonwoven fabric method), it is not limited to these.

In the fiber-reinforced plastic molding composite material of the present invention, voids are present in the sheet because the thermoplastic resin forming the matrix by thermoforming is in fiber form. Therefore, unlike composite materials in which the resin is completely buried between the fibers, such as melting method (hot melt method), solvent method, dry powder coating method, powder suspension method, resin film impregnation method (film stacking method), etc. Previously, the sheet itself is flexible and draped, and can be stored and transported in the form of winding, and can be heat-pressed after being placed along a curved mold. It is characterized by superiority.

The super engineering plastic fiber used for the fiber-reinforced plastic molding composite material of the present invention is sufficiently fluid under temperature conditions of 300 ° C. to 400 ° C. when the fiber-reinforced plastic molding composite material is heated and pressed. It is required to be. Further, the glass transition temperature of the fiberized super engineering plastic fiber should be 140 ° C. or higher so that the fiber state can be sufficiently maintained under the heating conditions applied in the production stage of the fiber reinforced plastic molding composite material. preferable. Further, even if the glass transition temperature is lower than this, it is preferable that the resin has a deflection temperature under load of 190 ° C. or higher.

Fiber reinforced plastic molding composites in which the resin that forms the matrix during heat and pressure molding is super engineering plastic fibers is heated when processed into fiber reinforced plastics rather than fiber reinforced plastic molding composites that use thermosetting resins. The original characteristic is that the pressure molding time is short and the productivity is excellent. However, in order to heat and pressure-mold a fiber reinforced plastic molding composite material in a short time, it is necessary for the super engineering plastic fiber to be used to quickly melt at a high temperature. Thinner fiber diameters are preferred. This is necessary for melting because the number of contact points between fibers increases when the fiber diameter is small, the contact area between the fibers increases, heat conduction becomes better, and the heat capacity of the fibers decreases. This is because the amount of heat is reduced. According to the study by the present inventors, the fiber diameter is preferably 30 μm or less, and more preferably 1 to 20 μm or less.

The fiber length of the super engineering plastic fiber is not particularly limited, but is preferably about 3 mm to 30 mm when manufactured by a wet or dry nonwoven fabric method. When longer than this, a fiber will not disperse | distribute uniformly but the uniformity of a sheet | seat and the uniformity of a mixing ratio with a reinforced fiber will fall. On the other hand, if the length is shorter than this, the strength of the web decreases, and breakage or the like is likely to occur in the manufacturing process of the fiber-reinforced plastic molding composite. The fiber diameter and fiber length may be single, or those having different fiber diameters and fiber lengths may be blended and used.

On the other hand, in order to obtain sufficient strength after heating and pressing, it is necessary to uniformly mix the reinforcing fibers and the matrix resin. For this purpose, it is preferable that the fiber diameters of the reinforcing fiber and the matrix resin fiber are close. From this viewpoint, the fiber diameter of the super engineering plastic fiber is preferably 4 times or less of the fiber diameter of the reinforcing fiber, more preferably 3 times or less, and most preferably the fiber diameter of the super engineering plastic fiber and the reinforcing fiber. The fiber diameter is almost the same.

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

As a preferable range of the fiber diameter of the super engineering plastic fiber, it is preferable to select a fiber having a fiber diameter of 30 μm or less and 4 times or less of the fiber diameter of the reinforcing fiber. Thereby, shortening of the heating and pressing time and the strength of the fiber reinforced plastic after the heating and pressing can be made compatible.

By the way, the fiber-reinforced plastic molding composite material manufactured by the melting method (hot melt method), solvent method, dry powder coating method, powder suspension method, resin film impregnation method (film stacking method), etc. If it is short, the air present between the composite material and the volatile gas generated from the composite material when the composite material and the heat-pressing plate or the fiber-reinforced plastic molding composite material are laminated and heated and pressed, etc. As a result, voids are generated. In particular, since the fiber reinforced plastic molding composite material using the super engineering plastic according to the present invention as a matrix resin needs to be heated and pressurized at a high temperature, such a problem is serious.

However, since the fiber reinforced plastic molding composite material of the present invention has a fibrous matrix and is highly air permeable, the air content existing between the press plate and the composite material and the volatile gas content generated from the composite material are , It is easy to slip out of the sheet during pressing, and has the characteristics that voids and the like are unlikely to occur even in a short time heating and pressing treatment.

In order to obtain such characteristics, it is preferable that the air permeability of the fiber reinforced plastic molding composite material is 200 seconds or less as measured by a method based on the JAPAN TAPPI paper pulp test method. This numerical value indicates that the smaller the number, the easier air can pass through (the better the air permeability).

However, as a material for satisfying the above air permeability, when the sheet before processing is adjusted to be bulky, since it is bulky until it is subjected to the heating and pressing step after the production of the fiber reinforced plastic molding composite, For example, there is a concern that problems such as excessive transportation costs or inconveniences when inserting into a heat press machine in the heating and pressurizing process may occur. The problem can be solved by lightly pressing with a heat press or a heat calender and increasing the density appropriately. In the case of this method, since air becomes somewhat difficult to pass, the air density measured by the method based on the JAPAN TAPPI paper pulp test method is increased to the extent that the air permeability can be maintained within 200 seconds.

The composite material for molding a fiber-reinforced plastic in the present invention can be manufactured using chopped strands in which matrix resin fibers and reinforcing fibers are cut into a predetermined length to shorten the length. In this case, the matrix resin and the reinforced fiber chopped strands are dispersed and mixed in the air, captured in a net and formed into a sheet, a so-called dry nonwoven fabric method, the matrix resin fibers and the reinforced fiber chopped strands in a solvent. The composite material for molding a fiber reinforced plastic can be produced by a so-called wet non-woven method or the like, which is then dispersed into a sheet and then formed into a sheet by removing the solvent.

When manufacturing by such a nonwoven fabric method, the strength as a sheet that can be handled may be insufficient only by physical entanglement between fibers. In that case, the super engineering plastic fibers may be partially melted by heating the sheet, and the fibers may be fused. A binder may be added to bind the fibers.

As binder components, thermosetting resins such as acrylic resin, styrene / acrylic resin, epoxy resin, phenol resin, thermoplastic resin such as urethane resin, polyester resin, polypropylene resin, polyethylene resin, ethylene / vinyl acetate resin, or polyvinyl What is used for general nonwoven fabric manufacture, such as resin which melts hot water like alcohol etc., can be used.

The binder content is preferably 10% by mass or less in the fiber-reinforced plastic molding composite. Such a binder component may start pyrolysis at the heating and pressing temperature of the fiber reinforced plastic molding composite material to generate gas. For this reason, if the binder content is higher than this, a large amount of gas is generated. Therefore, even if the fiber-reinforced plastic molding composite has the above-described air permeability, voids are formed in the fiber-reinforced plastic after heat and pressure molding. In addition, since the binder itself is discolored, the appearance and strength are often inferior.

In order to suppress the generation of voids due to gas generation as described above, the content of the binder component is preferably 10% by mass or less, more preferably 5% by mass or less, and still more preferably 1% with respect to the fiber reinforced plastic molding composite material. It is below mass%. If the amount of the binder is too small, the strength of the sheet is too weak to be broken during the operation, or fibers on the surface of the fiber-reinforced plastic molding composite material are easily dropped and scattered in the processing step, which is not preferable.

Also, the super engineering plastic fiber component used in the fiber-reinforced plastic molding composite material according to the present invention has a flame resistance because it has a critical oxygen index of 25 or more. However, since the limiting oxygen index of the binder component is generally lower than that of the super engineering plastic fiber component used in the fiber-reinforced plastic molding composite material of the present invention, the flame retardance is impaired when the binder content is large. Also from this viewpoint, the content of the binder is preferably 10% by mass or less, more preferably 5% by mass or less, and still more preferably 1% by mass or less with respect to the fiber-reinforced plastic molding composite material.

When polyphenylene sulfide (PPS) fiber is used as the super engineering plastic fiber used for the fiber-reinforced plastic molding composite in the present invention, the PPS resin has high chemical resistance and high heat resistance. A fiber reinforced plastic having excellent strength can be obtained.

When polyetherimide (PEI) fiber is used as the super engineering plastic fiber used for the fiber-reinforced plastic molding composite in the present invention, PEI resin has excellent adhesion to carbon fiber and glass fiber, and has a critical oxygen index of resin. Since it is very high at 47 in the block state, a fiber reinforced plastic excellent in strength and flame retardancy can be obtained.

When polyether ether ketone (PEEK) fiber is used as the super engineering plastic fiber used in the fiber reinforced plastic molding composite material in the present invention, the PEEK resin is particularly resistant to chemicals and high temperature compared to other super engineering plastics. A fiber reinforced plastic having excellent strength can be obtained.

The binder component used for the fiber-reinforced plastic molding composite material in the present invention is preferably unevenly distributed in the surface layer portion of the fiber-reinforced plastic molding composite material. In this case, the inner layer has relatively less binder component. By adopting such a configuration, even if a small amount of the binder component is used, dropping of the surface fibers is suppressed, and sufficient process strength during operation can be obtained. For example, in this case, the content of the binder component in the fiber-reinforced plastic molding composite can be 0.1 to 1.0% by mass.

As a method for making the binder component relatively present in the surface layer of the fiber reinforced plastic molding composite, after forming a web by a wet nonwoven fabric method or a dry nonwoven fabric method, a liquid material in which the binder component is dissolved in a solvent, or a binder The manufacturing method of giving the emulsion (emulsion) of a component by dipping or a spray method etc., and heat-drying is mentioned. According to this method, since the moisture inside the web moves to the surface layers on both sides and evaporates during heating and drying, a relatively large amount of the binder component concentrates on the surface layer as the moisture moves.

As described above, in order to make the binder component unevenly distributed on the surface layer of the fiber reinforced plastic molding composite material, a manufacturing method in which a liquid binder component such as a solution or emulsion of the binder component is used and dried by heating is employed. Can do. In this case, it is preferable that the solvent move more because the uneven distribution of the binder component becomes stronger.

When such a method is adopted, it is preferable to form a wet web by a wet nonwoven fabric method, then apply an aqueous binder solution or emulsion to the web by dipping or spraying, and then drying. In this case, the web moisture can be adjusted by adjusting the concentration of the binder solution in the aqueous solution or emulsion, or the moisture suction force by wet suction or dry suction in the wet nonwoven fabric manufacturing process.

The preferred web moisture for making the binder component unevenly distributed is 50% or more. However, if there is too much moisture, the drying load increases and the production cost increases. Therefore, it is preferable to appropriately adjust the moisture in consideration of both.

The degree of uneven distribution of the binder component can be grasped by dividing the sheet into approximately 3 to 5 parts in the thickness direction (Z-axis direction) and measuring the amount of each binder. The degree of uneven distribution of the binder component is preferably about 1/2 to 1/10 of the amount of binder in the inner layer with respect to the surface layer when divided into approximately three equal parts.

The binder component in the fiber-reinforced plastic molding composite material of the present invention is a resin component that is compatible with the resin when the super engineering plastic fiber that becomes the matrix after heat-pressure molding is melted by heat-pressure molding. Particularly preferred. When such a resin component is used as a binder, after heat and pressure molding, the matrix resin and the binder resin are integrated without any interface, and the strength is good. Further, the glass of the matrix resin caused by the binder resin It has the feature that there is little decrease in the transition temperature.

For example, when PEI fibers are used as a thermoplastic resin that becomes a matrix after heat and pressure molding, PET or modified PET is used as a preferable binder component in terms of being compatible with the resin when melted by heat and pressure molding. It is preferable.

When PET or modified PET is used as a binder, the shape is powder, fibrous, or ordinary PET placed on the core, and the periphery is covered with modified PET having a melting point lower than that of the core. A sheath-structured PET fiber or the like is preferably used. From the viewpoint of reducing the process strength of the fiber-reinforced plastic molding composite material and reducing the loss of surface fibers, the melting point of the modified PET is preferably 140 ° C. or less, more preferably 120 ° C. or less.

In one embodiment, the present invention comprises a non-woven sheet comprising a reinforcing fiber component composed of inorganic fibers, a matrix resin fiber component composed of polyetherimide fibers (PEI fibers), and at least one binder component. The fiber component in the surface layer part of a sheet-like sheet | seat is related with the composite material for fiber-reinforced plastics shaping | molding currently couple | bonded by the said binder component localized at the intersection of fiber components in the form of a water scraping film. Hereinafter, this embodiment will be particularly described.

The fiber-reinforced plastic molding composite material of the above embodiment includes a method of dispersing reinforcing fibers and PEI fibers in the air and capturing them in a net to form a web (dry nonwoven fabric method), and reinforcing fibers and PEI fibers in a solvent. And a method of forming a web after removing the solvent (wet nonwoven fabric method).

In the above-described embodiment, one of the features is that a liquid binder, that is, a binder component solution or an emulsion liquid, is used for the production of a fiber-reinforced plastic molding composite material. The liquid binder is concentrated on the fiber intersection by the surface tension of the binder liquid during the drying process after applying the binder to the web by the production process, that is, the coating method or the impregnation method, and then shrinks by drying. Therefore, after drying, as shown in FIG. Due to such a property, it is excellent in strength for bonding fibers even in a very small amount. The binder component is as described above.

Furthermore, as described above, when the web is dried, the moisture in the web containing the binder liquid evaporates from both surface layers of the fiber-reinforced plastic molding composite material. concentrate. Therefore, even if a small amount of the binder is used, the falling and scattering of the surface fibers of the composite material are suppressed, and a composite material for molding a fiber-reinforced plastic that has excellent handling properties in a heat molding process or the like can be obtained.

Further, by concentrating the binder on both surface layers of the fiber reinforced plastic molding composite material as described above, the flame retardancy and low smoke generation can be made excellent. The reason is considered as follows.

The method for unevenly distributing the binder component on the surface layer (both surface layers) of the fiber reinforced plastic molding composite is as described above.

In the above embodiment, the molding temperature is as high as 250 ° C. to 400 ° C. because polyetherimide having high heat resistance is used as the matrix resin. Such a temperature range exceeds the thermal decomposition temperature of an acrylic resin or the like normally used as a binder component. Therefore, it is considered that the binder component is thermally decomposed and volatilized at the time of thermoforming, so that the binder component does not remain in the thermoformed product, and thus the binder component does not hinder the flame retardancy and low smoke generation of the thermoformed product. However, in fiber reinforced plastic molding composites manufactured by the usual binder addition method, if the processing is carried out by heating and pressing for a short time, the molding process is completed before the binder components are sufficiently decomposed and volatilized. The remaining binder component inhibits the flame retardancy and low smoke generation of the thermoformed product.

By concentrating the binder component in the vicinity of the surface of the fiber reinforced plastic molding composite, the binder component is effectively heated during hot-press molding by a high-temperature mold or press plate. -It is considered that the binder component that volatilizes and remains in the thermoformed product becomes a very small amount.

In the above embodiment, the binder component used for the fiber-reinforced plastic molding composite material preferably contains a copolymer of methyl methacrylate, ethyl methacrylate, ethyl acrylate, and / or methyl acrylate, and particularly glass fiber or the like as the reinforcing fiber. In the case of a fiber reinforced plastic molding composite material using a material close to white, there is little coloring and this is preferable in appearance. In particular, the binder component preferably contains a copolymer containing at least one selected from methyl methacrylate and ethyl methacrylate as a monomer component.

Granular or fibrous binders can also be included in the fiber reinforced plastic molding composite. As a result, the interlayer strength of the fiber-reinforced plastic molding composite material is increased, and the handling property during the heat molding process is further improved.

A granular or fibrous binder can be dispersed in the air together with reinforcing fibers and PEI fibers and captured on a net to form a web (dry nonwoven fabric method), or dispersed in a solvent, and then the solvent is removed to remove the web. Can be contained in the fiber-reinforced plastic molding composite by a method such as a method of forming (wet nonwoven fabric method).

When supplied as a liquid binder or when supplied as a granular or fibrous binder, the binder component is preferably a binder component that is compatible with PEI fibers when heated and melted. According to the study by the present inventors, it has been found that when such a component is selected, the flame retardancy and low smoke generation of the PEI resin are hardly impaired after the heat and pressure molding.

As a component compatible with the PEI resin fiber when heated and melted, a polyester resin or a modified polyester resin may be mentioned. These resins can be used as an emulsion liquid or can be contained in the layer of the fiber-reinforced plastic molding composite material in a granular or fibrous form. In any case, the flame retardancy and low smoke generation properties of the PEI resin are not impaired, but a modified polyester resin is particularly preferable because the fusing temperature can be set so as to be suitable for the production process of the fiber-reinforced plastic molding composite.

In the above embodiment, the binder component used is a fiber reinforced plastic in which the total amount of the binder component supplied in the state of a solution or an emulsion and the binder component supplied in a granular or fibrous form, if necessary, It is preferable that it is 0.3 mass% or more and 10 mass% or less with respect to the shaping | molding composite material. The ratio of the two can be arbitrarily set so as to be suitable for the manufacturing process. When the amount of the binder component is less than 0.3% by mass, the strength during the manufacturing process is insufficient and the handling property is lowered. In addition, the above-mentioned binder component does not inhibit the flame retardancy and low smoke generation, but if the amount is too large, the flame retardancy and low smoke generation are likely to be impaired. It is 10% by mass or less, and sufficient process strength and handling properties can be obtained with this addition amount.

As described above, the liquid binder composed of methyl methacrylate, ethyl ethacrylate, ethyl acrylate, and / or methyl acrylate copolymer is concentrated on both surface layers of the fiber reinforced plastic molding composite, and the fiber components of both surface layers. Because it is localized in the form of a draining film at the intersection of each other, even if the binder component is small, it is suitable for the fiber reinforced plastic molding composite material because there is little loss of fibers on both surface layers even in the use process, and there is little discoloration. Immediately after papermaking, it can be suitably used in a process of cutting, laminating and pressing a flat plate.

On the other hand, after manufacturing the fiber reinforced plastic molding composite material, transporting it to another place and then cutting it to an appropriate size and performing the pressing process, it is more costly to transport it by winding the sheet. It is preferable in terms of the degree of freedom of the cut size. However, in the case of manufacturing winding, it is a normal method to wind the sheet while applying a predetermined tension so as not to cause winding deviation. In this case, the sheets are rubbed or rubbed in the winding process. Therefore, if the interlayer strength of the sheet is weak, delamination occurs, and handling properties after unwinding during use are extremely deteriorated.

Further, in general sheet manufacturing processes, winding is once manufactured with a paper machine or the like, and is further cut into a predetermined width while being wound with a winder or the like in order to obtain a predetermined width. In this case, the problem becomes more serious because the number of times the sheet is rolled is increased.

In such a case, as described above, the interlaminar strength can be improved by using a fibrous or granular binder. However, such a binder can be used for both fiber-reinforced plastic molding composites such as a liquid binder. Since it is not localized in the surface layer, most of the binder remains in the composite material even after the hot pressing. Therefore, the fibrous or granular binder is particularly preferably a binder that is compatible with the PEI resin, and is preferably a polyester resin or a modified polyester resin.

In particular, the fibrous binder is mixed with PEI fibers and reinforcing fibers and dispersed in water, and when the paper is made by a wet papermaking method, the yield drops by dropping from the eyes of the papermaking wire like a granular binder, It is particularly preferable because it is not unevenly distributed on the wire side. Taking these into consideration, a fibrous modified polyester resin binder is particularly suitable for producing a winding. Also, a binder fiber having a core-sheath structure in which a polyester resin is disposed in the core part and a modified polyester resin is disposed in the sheath part, and the melting point of the sheath part is lower than that of the core part can be suitably used.

Polyester resin is preferably polyethylene terephthalate (PET). The modified polyester resin is not particularly limited as long as the melting point is lowered by modifying the polyester resin, but modified polyethylene terephthalate is preferable. As the modified polyethylene terephthalate, copolymerized polyethylene terephthalate (CoPET) is preferable, and examples thereof include urethane-modified copolymerized polyethylene terephthalate. The copolymerized polyethylene terephthalate preferably has a melting point of 140 ° C. or lower, more preferably 120 ° C. or lower. A modified polyester resin as described in JP-B-1-30926 may be used. As a specific example of the modified polyester resin, in particular, Melty 4000 (a fiber in which all fibers are copolymerized polyethylene terephthalate) manufactured by Unitika is preferably exemplified. As the core-sheath-structured binder fiber, Melty 4080 manufactured by Unitika, N-720 manufactured by Kuraray, or the like can be suitably used.

With respect to the fiber reinforced plastic molding composite material, the emulsion binder is 0.7 to 4.0% by mass, the binder selected from the polyester resin and the modified polyester resin is 1.5 to 6.0% by mass, and the total amount of the binder components is When the content is 8% by mass or less, sufficient surface strength and interlayer strength can be obtained even when winding and repeated cutting.

When the amount of the binder component increases, both surface strength and interlayer strength increase, but conversely, the problem of odor during thermoforming tends to occur, and when the amount decreases, the problem of odor is reduced, but both surface strength and interlayer strength decrease. It becomes a trend. However, in the above range, there is hardly any odor problem, and a fiber-reinforced plastic molding composite material that does not cause delamination even after the repeated cutting steps as described above can be obtained.

In the above range, the blending amount of the liquid binder containing a copolymer of methyl methacrylate, ethyl ethacrylate, ethyl acrylate, and methyl acrylate as a component is smaller than that of the polyester resin or the modified polyester resin, and the odor is related. From these results, favorable results are obtained. Since the polyester binder is compatible with the matrix resin, it is difficult to generate odor even if the addition amount is relatively large, and since the liquid binder tends to be concentrated and concentrated at the intersection of the fibers, such a result is obtained. Estimated.

The fiber-reinforced plastic molding composite material of the present invention is a single sheet or laminated to have a desired thickness and heat-pressed by hot pressing, pre-heated with an infrared heater or the like in advance, ) A fiber reinforced plastic excellent in strength and flame retardancy can be obtained by processing using a general method for heating and pressing a fiber reinforced plastic molding composite material such as pressure molding.

The basis weight of the fiber-reinforced plastic molding composite material of the present invention is not particularly limited, but it is preferable to reduce the number of laminated layers because it is necessary to thermally decompose and volatilize the binder component on the surface of the fiber-reinforced plastic molding composite material during heat molding. Therefore, a higher basis weight is preferable. From such a viewpoint, the preferred basis weight is 400 g / m ² or more, more preferably 550 g / m ² or more. In addition, the upper limit of a fabric weight can be suitably set according to the thickness of the target fiber reinforced plastic molding composite material.

By forming the fiber reinforced plastic molding composite produced in the above process by heat and pressure molding, the smoke concentration after 20 minutes in the flame test measured by the method according to ASTM-662 is 43DS or less, It is possible to obtain a fiber-reinforced plastic molded article having a very low fuming property of 37 DS or less.

Hereinafter, the present invention will be described based on production examples for confirming the effects of the present invention, but the present invention is not limited thereto. In each production example, “part” and “%” represent “part by mass” and “% by mass” unless otherwise specified.

Production examples 1 to 4
A PAN-based carbon fiber having a fiber diameter of 7 μm and a fiber length of 13 mm and a PPS resin fiber having a fiber diameter shown in Table 1 (manufactured by Fiber Innovation Technology, fiber length of 13 mm, critical oxygen index of 41) and a mass ratio of polyacrylonitrile (PAN) ) It measured so that it might become the polyphenylene sulfide (PPS) resin fiber 60 with respect to the system carbon fiber 40, and it injected | thrown-in to water. The amount of water added was set to be 200 times the total mass of the PAN-based carbon fiber and the PPS resin fiber (that is, the fiber slurry concentration was 0.5%).

To this slurry, “Emanon 3199” (Kao Corporation, trade name) as a dispersant was added to 1 part by mass with respect to 100 parts by mass of fibers (total of PAN-based carbon fiber and PPS fiber), and the fibers were stirred. A fiber slurry uniformly dispersed in water was prepared.

Particulate polyvinyl alcohol (PVA) (Unitika Ltd., trade name “OV-N”) was added to water so as to have a concentration of 10%, and stirred to prepare a binder slurry. The granular PVA slurry was put into a fiber slurry, a wet web was formed by wet papermaking, and heat drying was performed at 180 ° C. to obtain a nonwoven fabric having a basis weight of 250 g / m ² .

This nonwoven fabric was heated and pressurized with a 220 ° C. hot press to obtain a fiber reinforced plastic molding composite material having air permeability shown in Table 1. In Production Example 2, the air pressure is adjusted as shown in Table 1 by shortening the heating and pressing time and lowering the density as compared with Production Example 1, and in Production Example 4 the heating and pressurization is more than in Production Example 1. The air permeability was adjusted as shown in Table 1 by extending the time and increasing the density.

In addition, the addition amount of granular PVA slurry density | concentration was adjusted suitably so that the compounding rate with respect to the composite material for fiber reinforced plastics shaping | molding of granular PVA may become as showing in Table 1.

Production Example 5
Except for changing the PPS resin fiber to the PPS fiber having the fiber diameter shown in Table 1 (manufactured by KB Selen Co., Ltd., glass transition temperature 92 ° C., fiber length 13 mm, critical oxygen index 41), the same as in Production Example 1 Thus, a composite material for molding fiber reinforced plastic was prepared.

Production Examples 6-9
The PAN-based carbon fiber having a fiber diameter of 7 μm and a fiber length of 13 mm in Production Example 1 was changed to a glass fiber having a fiber diameter of 9 μm and a fiber length of 18 mm, and the PPS resin fiber (manufactured by Fiber Innovation Technology Co., Ltd.) was produced. , Glass transition temperature 92 ° C., limiting oxygen index 41) to polyetherimide (PEI) resin fibers (Fiber Innovation Technology, glass transition temperature 220 ° C., fiber length 13 mm, limiting oxygen index 47) shown in Table 2. Except having changed, it carried out similarly to manufacture example 1, and obtained the nonwoven fabric whose fabric weight is 250 g / m < ² >. The obtained sheet was heated and pressed by a heat press at 220 ° C. to appropriately adjust the air permeability as shown in Table 2, and the fiber-reinforced plastic molding composite materials of Production Examples 6 and 7 were produced. In addition, in Production Example 7, the air permeability was adjusted as shown in Table 2 by shortening the heating and pressing time by 220 ° C. hot pressing and lowering the density as compared with Production Example 6.

Also, the same as Production Example 6 except that the granular PVA (Unitika Ltd., trade name “OV-N”) was changed to PET / coPET modified core-sheath binder fiber (Unitika Ltd., trade name “Melty 4080”). Thus, a fiber-reinforced plastic molding composite material of Production Example 8 was produced.

Further, the glass fiber in Production Example 6 was changed to glass fiber having a fiber diameter of 6 μm and a fiber length of 18 mm, and a fiber-reinforced plastic molding composite material of Production Example 9 was produced in the same manner as Production Example 6.

Production Examples 10-15
The PPS resin fiber in Production Example 1 was replaced with a PPS resin fiber having a fiber diameter of 16 μm (manufactured by Fiber Innovation Technology, glass transition temperature 92 ° C., fiber length 13 mm, critical oxygen index 41), and instead of granular PVA, a wet web was used. The composite material for molding fiber reinforced plastics of Production Examples 10 to 15 was the same as Production Example 1 except that the binder liquid shown in Table 3 was added in the amount shown in Table 3 by spraying after the formation, and was heated and dried. Was made.

Production Examples 16-21
Production Examples 10 to 15 except that the PPS resin fibers in Production Examples 10 to 15 are replaced with PEI resin fibers having a fiber diameter of 15 μm (manufactured by Fiber Innovation Technology, glass transition temperature 220 ° C., fiber length 13 mm, critical oxygen index 41). Fiber reinforced plastic molding composite materials of Production Examples 16 to 21 corresponding to the above were produced.

In the binder liquid, a PVA aqueous solution in which “PVA117” manufactured by Kuraray was dissolved in hot water was used as the PVA aqueous solution. The styrene acrylic emulsion used was “GM-1000” manufactured by DIC, and the urethane emulsion used was “AP-X101” manufactured by DIC.

Six fiber reinforced plastic molding composite materials obtained by the methods of the above production examples were laminated, inserted into a hot press preheated to 310 ° C., heated and pressurized for 60 seconds, and then cooled to 230 ° C. Thus, a fiber-reinforced plastic body was obtained.

Tables 1 to 4 show the appearance of the obtained fiber reinforced plastic and the bending strength measured by a method based on JIS K7074. Appearance is good with no voids, etc. ◎, slightly voids can only be confirmed ○, voids are generated but there is no practical problem, △, apparently due to voids Was bad and could not be used as a product.

As shown in Tables 1 to 4, the fiber reinforced plastic bodies obtained by heating and pressing the fiber reinforced plastic molding composites of Production Examples 1 and 2, Production Examples 6 to 8, and Production Examples 10 to 21 are as follows. It is manufactured by heat and pressure molding a gas-permeable fiber reinforced plastic molding composite material having a thermoplastic fiber called a super engineering plastic having a specific fiber diameter and a reinforcing fiber made of carbon fiber or glass fiber. As a result, the fiber-reinforced plastic body has high strength and good appearance.

The fiber reinforced plastic molded from the fiber reinforced plastic molding composite material of Production Example 4 having an air permeability of 210 and slightly less permeable than those of each of the above production examples is somewhat inferior in appearance. In addition, the strength is slightly lower than those of Production Examples 1 and 2. Further, in the case of the fiber reinforced plastic body obtained by molding the composite material for fiber reinforced plastic molding of Production Example 5, the fiber diameter of the super engineering plastic fiber exceeds 30 μm, so that the appearance after heating and pressing is that of Production Examples 1 to 4. It is clearly inferior to a fiber reinforced plastic body molded from a fiber reinforced plastic molding composite. Moreover, in the case of the fiber reinforced plastic body which shape | molded the fiber reinforced plastic molding composite material of the manufacture example 9, the fiber reinforcement is carried out by using the super engineering plastic fiber which has a fiber diameter exceeding 4 times the fiber diameter of a reinforcement fiber Fiber reinforcement in which the mixed state of the reinforcing fiber and matrix fiber in the plastic molding composite material is deteriorated, and the appearance of the laminate after the heat and pressure molding is molded from the fiber reinforced plastic molding composite material of Production Examples 1 to 4 It is clearly inferior to the plastic body.

In addition, what is shape | molded from the composite material for fiber reinforced plastic molding of the manufacture example 3 is fiber because the amount of binders in the composite material for fiber reinforced plastic molding is larger than that of the manufacture examples 1 and 2. In the composite material for molding fiber reinforced plastic of the present invention, the content of the binder used is also the fiber reinforced plastic after molding so that the appearance of the reinforced plastic body is slightly inferior to those of Production Examples 1 and 2. It can be seen that this affects the appearance and strength.

Example 1
A PAN-based carbon fiber having a fiber diameter of 7 μm and a fiber length of 13 mm and a PEI resin fiber having a fiber diameter of 15 μm (fiber length of 13 mm) are set to have a PEI resin fiber 60 with respect to the polyacrylonitrile (PAN) -based carbon fiber 40. Weighed and put into water. The amount of water added was 200 times the total mass of the PAN-based carbon fiber and the PEI resin fiber (that is, the fiber slurry concentration was 0.5%).

To this slurry, “Emanon 3199” (Kao Corporation, trade name) as a dispersant was added to 1 part by mass with respect to 100 parts by mass of fibers (total of PAN-based carbon fibers and PEI fibers), and the fibers were stirred. A fiber slurry uniformly dispersed in water was prepared.

A wet web is formed from this fiber slurry by a wet papermaking method, and an emulsion liquid binder (methyl methacrylate copolymer, EMN-188E manufactured by Nippon Shokubai Co., Ltd.) having a concentration of 5% is applied by a spray method. As shown in Table 5, the web moisture was appropriately dehydrated by suction, and heated and dried at 180 ° C. to obtain a fiber-reinforced plastic molding composite material having a basis weight of 550 g / m ² .

Example 2
A binder slurry liquid in which a modified polyester granular binder (powder resin G-120, manufactured by Tokyo Ink Co., Ltd.) having a melting point of 110 ° C. was dispersed in water so as to have a solid content mass concentration of 10% was prepared. Except for adding this binder slurry liquid to the fiber slurry prepared in Example 1, a wet web is formed by the wet papermaking method in the same manner as in Example 1, and an emulsion liquid binder is added to heat and dry the fabric. A fiber-reinforced plastic molding composite material having a weight of 550 g / m ² was obtained. In addition, the addition amount of the binder slurry liquid was adjusted so that the solid content mass addition amount of the modified polyester granular binder was as shown in Table 5.

Example 3
In Example 2, a fiber reinforced plastic molding composite was obtained in the same manner as in Example 2 except that the modified polyester granular binder having a melting point of 110 ° C. was changed to a modified polyester fibrous binder (Melty 4000 manufactured by Unitika).

Example 4
In Example 1, the emulsion liquid binder was changed to a 2% concentration PVA solution binder (Kuraray PVA117 dissolved in warm water and cooled), and the solid mass addition amount of the binder to the fiber-reinforced plastic molding composite was changed to A fiber-reinforced plastic molding composite material was obtained in the same manner as in Example 1 except that it was as shown in Table 5.

Example 5
A fiber-reinforced plastic molding composite was produced in the same manner as in Example 2 except that the modified polyester granular binder in Example 2 was changed to PVA granular binder (OV-N manufactured by Unitika Ltd.).

Comparative Example 1
In Example 5, a fiber reinforced plastic molding composite was produced in the same manner as in Example 5 except that the emulsion liquid binder was not applied and the addition amount of the granular PVA binder was changed as shown in Table 5.

Comparative Example 2
A fiber reinforced plastic molding composite was produced in the same manner as in Comparative Example 1, except that the amount of the granular PVA binder added was changed as shown in Table 5.

Comparative Examples 3-4
In Comparative Examples 1 and 2, the reinforcing fiber was changed to a glass fiber having a fiber diameter of 9 μm and a fiber length of 18 mm, and the ratio of the reinforcing fiber to the polyetherimide fiber was changed as shown in Table 6. Comparative Example 1 A composite material for molding a fiber-reinforced plastic was produced in the same manner as in (2).

Examples 11 to 26
The solid content of the methyl methacrylate copolymer (EMC-188E manufactured by Nippon Shokubai Co., Ltd.) is as shown in Table 5, and the solid content of the modified polyester fibrous binder (Melty 4000 manufactured by Unitika) is also shown. A composite material for molding a fiber-reinforced plastic was obtained in the same manner as in Example 3 except that it was as shown in FIG. The solid content of the binder (EMN-188E manufactured by Nippon Shokubai Co., Ltd.), which is a methyl methacrylate copolymer, was adjusted to a predetermined level by appropriately adjusting the spray liquid concentration at the time of adding the binder.

Example 27
A fiber reinforced plastic molding composite was prepared in the same manner as in Example 1 except that the solid content of the emulsion liquid binder (methyl methacrylate copolymer, EMN-188E manufactured by Nippon Shokubai Co., Ltd.) was as shown in Table 6. Manufactured. The solid content of the binder (EMN-188E manufactured by Nippon Shokubai Co., Ltd.), which is a methyl methacrylate copolymer, was adjusted to a predetermined level by appropriately adjusting the spray liquid concentration at the time of adding the binder.

Examples 28-44
In Examples 11 to 27, Example 11 was changed except that the reinforcing fiber was changed to a glass fiber having a fiber diameter of 9 μm and a fiber length of 18 mm, and the ratio of the reinforcing fiber to the polyetherimide fiber was changed as shown in Table 6. In the same manner as in ˜27, fiber reinforced plastic molding composite materials of Examples 23˜44 were produced.

Six fiber reinforced plastic molding composites obtained by the methods of the above Examples and Comparative Examples were stacked, inserted into a hot press preheated to 310 ° C., heated and pressurized for 60 seconds, and then 180 The fiber-reinforced plastic body was obtained by cooling to ° C.

The dropping and scattering of the surface fibers of the composite material for molding fiber-reinforced plastic during the heating and pressing operation and the ease of handling (handling properties) were evaluated as follows.
A: Very good B: Good and can be handled without problems in practical use C: Slightly problematic in practical use, but can be manufactured D: There are very many surface fibers falling off, which is clearly a problem in mass production Occurrence, and the sheet is easily torn and has poor handling

Moreover, about the odor which generate | occur | produced during 60 second heating and pressurization, it evaluated as follows.
A: No odor at all B: Some odor but little concern C: No odor but no problem when working D: Strong odor but mask for short work Items that can be operated even if there is no etc. E: Items that require a mask to work with strong odor

By the method of each of the above examples and comparative examples, each fiber reinforced plastic molding composite material having a width of 2.3 m was manufactured, and (1) cut with a two-drum winder so as to have a width of 1100 mm. A winding was obtained. (2) The winding obtained in the previous period (1) was further cut with a two-drum winder so as to have a width of 500 mm to obtain a winding of 300 m. Then, the dropping and scattering of the surface fibers of the fiber reinforced plastic molding composite material during the operations (1) and (2) were evaluated as follows.
A: Very good with very little scattering of fibers B: Good with little scattering of fibers and can be handled without problems in practice C: Many scattering of fibers causes some practical problems, but production is possible Things D: There is a lot of surface fiber falling off, which obviously causes problems in mass production

Moreover, the composite material for fiber-reinforced plastic molding after the steps (1) and (2) were evaluated as follows.
A: Delamination did not occur B: Interlaminar strength slightly weakened, but practically usable and could be handled C: Delamination occurred in part, causing some problems in practical use, but handling is possible Some D: Delamination occurs on the entire surface, causing problems in handling

Table 5 and Table 6 show the smoke concentration (according to ASTM E-662, after heating for 20 minutes) and the limiting oxygen index of the obtained fiber reinforced plastic by the flame method.

* In Tables 5 and 6 above, “granular polyester” represents a modified polyester granular binder (powder resin G-120, manufactured by Tokyo Ink Co., Ltd.), and “fibrous polyester” represents a modified polyester fibrous binder (manufactured by Unitika). 4000).

As shown in Tables 5 and 6, the fiber-reinforced plastic molding composites according to the present invention are less likely to lose surface fibers, have sufficient sheet strength, and have good handling properties in the work process. The fiber reinforced plastic body showed excellent flame retardancy, that is, low smoke concentration and high limit oxygen index. Further, Examples 2, 3, 7 and 8 using granular polyester and fibrous polyester, which are binders compatible with polyetherimide, are particularly difficult to handle, in addition to excellent handling properties. It showed flammability, that is, low smoke concentration and high critical oxygen index.

On the other hand, in the comparative example in which no liquid binder is used, the surface fibers often fall off, the sheet is not easily handled, and the flame retardant plastic body is inferior in flame retardancy. Increasing the amount of binder to improve surface fiber shedding and sheet handling results in further inferior flame retardancy of the fiber reinforced plastic body.

The fiber-reinforced plastic molding composite material of the present invention contains a thermoplastic super engineering plastic fiber having high heat resistance and high flame retardancy as a matrix resin component, so that the productivity of the fiber-reinforced plastic molding composite material itself is high. Excellent handling in processing.

The composite material for molding fiber reinforced plastics, which is a nonwoven fabric structure containing thermoplastic polyetherimide fibers with excellent heat resistance and flame retardancy as matrix resin components and inorganic fibers as reinforcing fiber components, is a surface layer. Since the fiber components of the parts are mainly bonded and fixed with a small amount of binder, the handleability in the processing process is also excellent.

Since the fiber-reinforced plastic molding composite material of the present invention can be molded into a fiber-reinforced resin molded article having high strength, high heat resistance and excellent flame retardancy, a lightweight and high-strength composite material is required. It is useful as sports equipment, leisure equipment, aircraft materials, etc.

All publications, patents and patent applications cited in this specification shall be incorporated into this specification as they are.

1: Fiber constituting non-woven fabric 2: Drip film binder

Claims (26)

1. Reinforcing fiber component comprising at least one inorganic fiber selected from glass fiber and carbon fiber, heat having a limiting oxygen index of 25 or more, a fiber diameter of 30 μm or less, and 4 times or less of the fiber diameter of the reinforcing fiber A fiber-reinforced plastic molding composite comprising a matrix resin component made of a plastic super engineering plastic fiber.
2. JAPAN TAPPI Paper Pulp Test Method No. The fiber-reinforced plastic molding composite material according to claim 1, wherein the air permeability defined in 5-2 is 200 seconds or less.
3. The composite material for fiber-reinforced plastic molding according to claim 1 or 2, wherein both the super engineering plastic fiber and the reinforcing fiber are chopped strands and are formed into a nonwoven fabric sheet by a dry nonwoven fabric method or a wet nonwoven fabric method.
4. The fiber-reinforced plastic molding composite material according to any one of claims 1 to 3, wherein the fiber-reinforced plastic molding composite material contains a binder component in an amount of up to 10% by mass.
5. 5. The fiber according to claim 4, wherein the binder component in the fiber-reinforced plastic molding composite material is unevenly distributed so that many portions thereof are present on a surface layer portion of the fiber-reinforced plastic molding composite material. Composite material for molding reinforced plastics.
6. The binder component is compatible with the matrix resin component made of the super engineering plastic fiber, and the composite material is heated and pressed at a temperature of 250 ° C. or higher and 430 ° C. or lower between the super engineering plastic fiber. 6. The composite material for molding a fiber-reinforced plastic according to claim 4 or 5, wherein the composite material is an integrated resin component having no interface.
7. The fiber-reinforced plastic according to any one of claims 4 to 6, wherein the binder component is applied to the nonwoven fabric sheet by a coating method or an impregnation method as a solution or an emulsion containing the binder component. Composite material for molding.
8. The fiber-reinforced plastic molding composite material according to any one of claims 1 to 7, wherein a fiber diameter of the super engineering plastic fiber is 1 to 20 µm.
9. The fiber-reinforced plastic molding composite material according to any one of claims 1 to 8, wherein the super engineering plastic fiber is a polyetherimide (PEI) fiber.
10. 10. The fiber-reinforced plastic molding composite material according to claim 9, wherein the binder component comprises polyethylene terephthalate (PET) or modified polyethylene terephthalate (PET).
11. Reinforcing fiber component comprising at least one inorganic fiber selected from glass fiber and carbon fiber, heat having a limiting oxygen index of 25 or more, a fiber diameter of 30 μm or less, and 4 times or less of the fiber diameter of the reinforcing fiber A method for producing a fiber-reinforced plastic molding composite, comprising a step of mixing a matrix resin component made of plastic super engineering plastic fibers to form a nonwoven fabric sheet.
12. The method for producing a fiber-reinforced plastic molding composite material according to claim 11, wherein the step of forming the nonwoven fabric sheet is a nonwoven fabric forming step of either a dry nonwoven fabric method or a wet nonwoven fabric method.
13. The step of forming the nonwoven fabric sheet includes a step of forming a nonwoven fabric sheet in which many parts of the binder amount contained in all the nonwoven fabric sheets are unevenly distributed on the front and back surface portions of the nonwoven fabric sheet using a binder-containing liquid. 13. The method for producing a fiber-reinforced plastic molding composite material according to claim 11 or 12, wherein
14. The step of forming the nonwoven fabric sheet includes a step of heat-treating the nonwoven fabric sheet having a matrix resin component composed of the reinforcing fiber component and the super engineering plastic fiber under conditions in which the super engineering plastic fiber is partially melted. The method for producing a fiber-reinforced plastic molding composite material according to any one of claims 11 to 13.
15. The fiber reinforced plastic molding composite material according to any one of claims 1 to 10 is formed by pressure and heat molding under a condition in which a matrix resin component made of the super engineering plastic fiber melts. A fiber-reinforced plastic molding.
16. Reinforced fiber component made of inorganic fiber, matrix resin fiber component made of polyetherimide fiber, and non-woven sheet containing binder component, and the fiber components in the surface layer part of the non-woven sheet are mainly intersections of the fiber components A fiber-reinforced plastic molding composite material, wherein the composite material is bonded to the binder component localized in the form of a water-slipping film.
17. Among the binder components, the binder component that is localized in the form of a scraping film at the intersection of the fiber components in the surface layer portion contains a copolymer containing at least one selected from methyl methacrylate and ethyl methacrylate as the monomer component. The composite material for fiber-reinforced plastic molding according to claim 16, wherein:
18. The fiber according to claim 16 or 17, wherein at least one of the binder components is a particulate or fibrous thermoplastic resin that is compatible with the polyetherimide fiber component in a heated and melted state. Composite material for molding reinforced plastics.
19. 19. The fiber-reinforced plastic molding composite material according to claim 18, wherein the particulate or fibrous thermoplastic resin contains at least one selected from a polyester resin and a modified polyester resin.
20. The composite material for fiber-reinforced plastic molding according to any one of claims 16 to 19, wherein the total content of the binder component is 0.3 mass% or more and 10 mass% or less.
21. The binder component contains a copolymer containing at least one selected from methyl methacrylate and ethyl methacrylate as a monomer component, and at least one fibrous resin selected from a fibrous polyester resin and a fibrous modified polyester resin. The content of the copolymer with respect to the fiber-reinforced plastic molding composite is 0.7 to 4.0% by mass, and the content of the fibrous resin with respect to the fiber-reinforced plastic molding composite is 1.5% by mass. The composite material for fiber-reinforced plastic molding according to claim 20, wherein the composite material is -6 mass% and the total content of binder components is 8 mass% or less.
22. The fiber component in the intermediate layer between the surface layer portions is bonded to the polyetherimide fiber component by a particulate or fibrous thermoplastic resin that is compatible in the heat-melted state. 21. The fiber-reinforced plastic molding composite material according to any one of 21.
23. A method for producing a fiber-reinforced plastic molding composite material according to any one of claims 16 to 22, comprising a reinforcing fiber component comprising the inorganic fibers and a matrix resin fiber component comprising the polyetherimide fibers. By applying a solution-type or emulsion-type binder liquid to the nonwoven fabric, and then drying the entire nonwoven fabric while rapidly heating the nonwoven fabric to transfer the main part of the binder liquid to the nonwoven fabric surface layer portion, A method for producing a composite material for molding a fiber-reinforced plastic, characterized in that the intersections of fiber components are bound together by a binder that is localized in the form of a water web.
24. 23. A fiber-reinforced plastic molded article formed by heat-pressing the composite material for molding a fiber-reinforced plastic according to claim 16 at a temperature of 250 ° C. or higher and 430 ° C. or lower.
25. The fiber-reinforced plastic molded product according to claim 24, wherein the smoke concentration after 20 minutes of combustion in a flammable method in accordance with ASTM E662 is 43DS or less.
26. 26. The fiber-reinforced plastic molded article according to claim 24 or 25, wherein a limiting oxygen index measured according to JIS K-7102-2 is 40 or more.

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