JP2006160972A - Fiber-reinforced resin composite material, resin composition, and prepreg - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a fiber-reinforced resin composite material having excellent low-temperature curability, mechanical characteristics, and ignition resistance, and to provide a prepreg for obtaining the fiber-reinforced resin composite material. <P>SOLUTION: The fiber-reinforced resin composite material contains a fiber-reinforced material and a matrix resin composition, wherein the interlayer shear strength of the fiber-reinforced resin composite material that is obtained by 5 or less hours of curing at 100°C is 60 MPa or more, the glass transition temperature of 50°C or higher, and the fiber-reinforced resin composite material with a thickness of 2 mm or less is inflammable as determined based on a firing test according to Tetsu-un (Railway rule) No. 81 of the Ministry of Land, Infrastructure and Transport. The matrix resin composition contains the following essential components: (A) an epoxy resin, (B) a curing agent and a curing accelerator, (C) a metal oxide, and (D) a thermoplastic resin. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to a fiber reinforced resin composite material excellent in low-temperature curability and mechanical properties, and excellent in ignition resistance, and a prepreg for obtaining the fiber reinforced resin composite material. More specifically, the present invention relates to a fiber reinforced resin composite material and a prepreg that are optimal for use in transportation such as railway vehicles.

  Fiber reinforced resin composite materials are widely used from sports / leisure applications to industrial applications such as automobiles and aircraft, taking advantage of their light weight, high strength, and high rigidity. In particular, automobiles, railway vehicles, airplanes, and the like for industrial use are increasingly required to be lighter in recent years, and the use of FRP is expanding. Among industrial uses, materials used for automobiles, railway vehicles and the like are required to have flame retardancy in addition to mechanical properties, and fiber reinforced resin composite materials used for such uses are also required to have flame retardance.

  As a method for molding such a fiber reinforced resin composite material, there is a method using a prepreg in which a fiber reinforcing material is impregnated with a resin composition. Of course, prepregs used for applications requiring flame retardancy are required to have high flame retardancy after molding. In particular, fiber reinforced resin composite materials used in railway vehicles are emphasized not to be ignited first, and the criterion for the ignition test in accordance with the Ministry of Land, Infrastructure, Transport and Tourism Iron Transport No. 81 is required to be nonflammable. .

  Conventionally, the method of making a fiber reinforced resin composite material incombustible has been to reduce the local temperature rise by increasing the thickness of the fiber reinforced resin composite material, thereby diffusing and dissipating the heat from combustion, thereby reinforcing the fiber. It acts to prevent ignition associated with temperature rise of the resin composite material. This action can meet the non-flammability standards required by the industry such as railway vehicles. However, this method is not necessarily a preferred method because the thickness of the fiber reinforced resin composite material is increased and the weight thereof is increased and the effect of weight reduction using the fiber reinforced resin composite material is impaired.

  Japanese Patent Application Laid-Open No. 11-147965 (Patent Document 1) and Japanese Patent Application Laid-Open No. 2003-20410 (Patent Document 2) disclose that the fiber-reinforced resin composite material has a relatively thin thickness of 2 mm and is a non-flammable standard. A method for satisfying this has been proposed. In these methods, a fiber reinforced resin composite material is obtained by heating and pressure molding at 125 ° C. or higher using an autoclave.

  The equipment of the autoclave is very expensive, so it is not only difficult to introduce it to the production site, but once it is introduced, the size of the molded product is limited by the size of the autoclave and the production of larger molded products Is virtually impossible. In addition, metal molds that are excellent in heat resistance and pressure resistance are used as molds that can be used for heating and pressure molding at 125 ° C. or higher. However, such metal molds are time-consuming and expensive. is there.

  From this point of view, development of de-autoclave molding and low-cost molding has been actively carried out, and typical examples thereof are oven molding (also called vacuum bag molding) in which molding is performed under a low pressure of only atmospheric pressure by reduced pressure. .) In this oven molding, no pressure other than atmospheric pressure is applied, so there is no need for a solid pressure-resistant container such as an autoclave, and molding is possible if there is an oven (oven) that can raise the temperature. According to this method, for example, molding can be performed with simple equipment such as a heat insulating board and a hot air heater. Furthermore, if it can be molded at 100 ° C. or lower, it is possible to use gypsum and wood that are inexpensive and easy to process as a mold material. Thereby, it is considered that a large-sized structure portion such as a trunk portion of a railway vehicle can be easily manufactured at a lower cost.

  However, the resin compositions described in JP-A-11-147965 and JP-A-2003-20410 have insufficient mechanical properties due to insufficient curing of the resin composition even when oven-molded at 100 ° C. or lower. It did not appear, and the non-flammability standards required by industries such as railway vehicles could not be met.

Japanese Patent Laid-Open No. 11-147965 JP 2003-20410 A

  An object of the present invention is to provide a fiber reinforced resin composite material that can be oven-molded, has excellent mechanical properties, and has excellent ignition resistance, and a prepreg for obtaining the fiber reinforced resin composite material.

  The above-described problems can be solved by the fiber reinforced resin composite material of the present invention or the prepreg for obtaining the fiber reinforced resin composite material.

  That is, the fiber reinforced resin composite material of the present invention is a fiber reinforced resin composite material including a fiber reinforced material and a resin composition, and the interlaminar shear of the fiber reinforced resin composite material obtained by curing within 100 hours at 100 ° C. Judgment of the ignition test based on the Ministry of Land, Infrastructure, Transport and Tourism Iron and Steel No. 81 using a fiber reinforced resin composite material having a strength of 60 MPa or more, a glass transition temperature of 50 ° C. or more, and a thickness of 2 mm is incombustible. Is.

  In the present invention, the fiber reinforcing material is a fiber reinforced resin composite material having a thermal conductivity of 5 W / m · K or more and a volume content of the fiber reinforcing material to the fiber reinforced resin composite material of 45 to 70%. The fiber is preferably a fiber reinforced resin composite material having an interlayer shear strength of 70 MPa or more and a glass transition temperature of 80 ° C. or more.

In the present invention, the cured product obtained by curing the resin composition at 100 ° C. within 5 hours has a mass loss at 300 ° C. to 350 ° C. of 3% or less with respect to the mass at 50 ° C. The fiber reinforced resin composite material is preferably a fiber reinforced resin composite material in which the blending mass ratio of the components (A), (B), (C), and (D) is the following ratio: Is preferred.
(A) Epoxy resin: 100 parts by mass (B) Curing agent, curing accelerator: 4 parts by mass or less (C) Metal oxide: 5-40 parts by mass (D) Thermoplastic resin: 5-90 parts by mass

  In the present invention, the component (B) is preferably a fiber reinforced resin composite material in which the urea compound is used alone or in combination with dicyandiamide, and the urea compound in the component (B) is phenyldimethylurea or toluenedimethylurea. It is preferable that it is a fiber reinforced resin composite material.

  In the present invention, a fiber reinforced resin composite material in which the thermal conductivity of the component (C) is 20 W / m · K or more and the average particle size is 10 μm or less is preferable, and the fiber reinforced resin in which the component (D) is a phenoxy resin. A resin composite material is preferable.

  According to the present invention, there is further provided a prepreg obtained by impregnating a fiber reinforcement with the resin composition.

  According to the present invention having the above-described configuration, it is possible to provide a fiber reinforced resin composite material capable of being oven-molded, excellent in mechanical properties, and excellent in ignition resistance, and a prepreg for obtaining the fiber reinforced resin composite material. .

  The fiber reinforced resin composite material produced using the prepreg of the present invention has excellent ignition resistance and mechanical properties, and is particularly suitable for railway vehicle applications. Furthermore, since the molding can be performed at 100 ° C., a large structure can be integrally molded with an inexpensive oven molding facility without using an autoclave, so that the weight can be further reduced.

  Hereinafter, the present invention will be described more specifically with reference to the drawings as necessary. In the following description, “parts” and “%” representing the quantity ratio are based on mass unless otherwise specified.

(Fiber reinforced resin composite material)
As a result of intensive studies to solve the above-described problems of the prior art, the present inventor has found that a fiber-reinforced resin composite material having a specific function can solve such problems all at once. . That is, in the present invention, the fiber reinforced resin composite material is a fiber reinforced resin composite material including a fiber reinforcing material and a resin composition, and the fiber reinforced resin composite material obtained by curing within 100 hours at 100 ° C. The interlaminar shear strength is 60 MPa or higher, the glass transition temperature is 50 ° C. or higher, and the thickness is 2 mm. The above-mentioned problems of the prior art are solved by the fiber reinforced resin composite material (or the prepreg for obtaining the fiber reinforced resin composite material). This is because the fiber-reinforced resin composite material of the present invention is excellent in low-temperature curability and mechanical properties, and in addition, is excellent in ignition resistance.

(Fiber reinforcement)
In the present invention, the fiber reinforcement is not particularly limited, but the thermal conductivity is preferably 5 W / m · K or more from the viewpoint of ignition resistance. Examples of the fiber reinforcing material having such a thermal conductivity of 5 W / m · K or more include carbon fiber, silicon carbide fiber, and boron fiber. The shape of these fiber reinforcements is preferably a continuous fiber from the viewpoint of ignition resistance. Examples of the continuous fiber shape include a long fiber, a sheet shape, a fabric shape, a knitted shape, a mat shape, and a paper shape. The thermal conductivity of the fiber reinforcement shown here is 27 ° C., which is a measured value in the fiber direction.

  In the present invention, the volume content of the fiber reinforcement in the fiber reinforced resin composite material is preferably 45 to 70%. When the volume content of the fiber reinforcement is 45% or less, it tends to be difficult to develop sufficient mechanical properties, and the thermal conductivity of the fiber reinforced resin composite material tends to decrease. It is not preferable also from a viewpoint. On the other hand, if the volume content of the fiber reinforcement exceeds 70%, it is difficult to develop sufficient mechanical properties, which is not preferable. The volume content of the fiber reinforcement is more preferably 50 to 70%.

((A) component)
The epoxy resin of component (A) that can be used in the resin composition in the present invention is not particularly limited. For example, as such an epoxy resin, bisphenol type epoxy resin, aminoglycidyl type epoxy resin, aminophenol type epoxy resin, novolac type epoxy resin, naphthalene type epoxy resin, aliphatic, alicyclic epoxy resin, isocyanate modified epoxy resin, etc. Is mentioned. As the epoxy resin of component (A), the above-described resins may be used alone, or two or more kinds may be used in combination as necessary.

((B) component)
The curing agent and curing accelerator of component (B) that can be used in the resin composition in the present invention are not particularly limited. From the viewpoint of curability and storage stability, examples of such component (B) include urea compounds, dicyandiamide (Dicy), and the like, and they can be used alone or in combination as necessary. Examples of urea compounds include alkyl urea compounds such as 3- (3.4-dichlorophenyl) -1.1-dimethylurea (DCMU), phenyldimethylurea (PDMU), and toluenebisdimethylurea (TBDMU). Among these, phenyldimethylurea (PDMU) and toluenebisdimethylurea (TBDMU) are particularly preferable because they have excellent curability at 100 ° C. or less. Examples of the phenyldimethylurea (PDMU) include Omicure 94 manufactured by PTI Japan, and examples of toluenebisdimethylurea (TBDMU) include Omicure 24 manufactured by PTI Japan.

((C) component)
The metal oxide of component (C) that can be used in the resin composition in the present invention is not particularly limited. Such a metal oxide preferably has a thermal conductivity of 20 W / m · K or more and an average particle size of 10 μm or less. When the thermal conductivity is 20 W / m · K or more, better ignition resistance can be obtained. On the other hand, when the average particle diameter of the metal oxide exceeds 10 μm, the metal oxide tends to form a fill trait between the filaments of the fiber reinforcing material and become a defect in the fiber reinforced resin composite material, so that the mechanical properties tend to decrease. is there. The average particle size shown here is a value at which the particle size distribution is 50%. Examples of the metal oxide having a thermal conductivity of 20 W / m · K or higher include magnesium oxide and aluminum oxide. Magnesium oxide having a particularly high thermal conductivity is useful because it has excellent ignition resistance. The thermal conductivity of the metal oxide shown here is a measured value at 27 ° C.

((D) component)
The thermoplastic resin of component (D) that can be used in the resin composition in the present invention is not particularly limited, but it is preferable to use a phenoxy resin from the viewpoint of ignition resistance. This is because the phenoxy resin is excellent in self-extinguishing properties.

  If the DSC curing degree of the cured product obtained by curing the resin composition in the present invention at 100 ° C. for 5 hours or less is 70% or more and less than 70%, sufficient mechanical properties are not exhibited and ignition resistance is also inferior. More preferably, it is 80% or more, More preferably, it is 90% or more.

  The mass reduction | decrease in 300 to 350 degreeC is 3% or less with respect to the mass in 50 degreeC of the hardened | cured material which hardened the resin composition in this invention within 100 degreeC and 5 hours. If the mass reduction exceeds 3%, the ignition resistance is poor. Preferably it is 1.5% or less.

(Preferable content ratio)
It is preferable that the hardening agent and hardening accelerator (B) which are a component are 4 mass parts or less with respect to 100 mass parts of (A) component. When the content ratio of the component (B) is 4 parts by mass or less, the curing agent and the curing accelerator do not tend to thermally decompose from 300 ° C. or higher, and sufficient ignitability is obtained. The content ratio of the component (B) is more preferably 3.5 to 1.5 parts by mass.
(C) It is preferable that the metal oxide which is a component is 5-40 mass parts with respect to 100 mass parts of (A) component. When the content ratio of the component (C) is 5 parts by mass or more, sufficient ignition resistance is obtained, and within 40 parts by mass, the mechanical properties are not significantly reduced. The content ratio of the component (C) is more preferably 15 to 40 parts by mass, still more preferably 25 to 40 parts by mass.

  (D) It is preferable that the thermoplastic resin which is a component is 5-90 mass parts with respect to 100 mass parts of (A) component. When the content ratio of the component (D) is 5 parts by mass or less, there is sufficient ignitability, and when it is 90 parts by mass or less, the deterioration of the handleability due to the increase in viscosity is not remarkable, and the fiber reinforced material is impregnated during prepreg production. There is no adverse effect. The content ratio of the component (D) is more preferably 15 to 60 parts by mass, still more preferably 25 to 50 parts by mass.

  The components (A), (B), (C), and (D) described above are preferably selected within the range of the content ratio described above.

(Fiber reinforcement)
As long as the above-mentioned predetermined physical properties are given, the fiber reinforcing material usable for the prepreg of the present invention is not particularly limited.

  The form of the fiber reinforcing material used in the prepreg of the present invention is preferably a continuous fiber-like shape that can further diffuse and dissipate heat from combustion from the viewpoint of ignition resistance. Examples of such a continuous fiber shape include a long fiber, a sheet shape, a fabric shape, a knitted shape, a mat shape, and a paper shape.

(Various test methods)
In the present invention, various tests such as interlaminar shear strength, glass transition temperature, ignition test, reinforcing fiber volume content, DSC curing degree, weight reduction, and the like are performed according to the following methods.

[Interlaminar shear strength]
After laminating and forming the prepreg, the interlaminar shear strength (ILSS) is measured according to ASTM D2344.

〔Glass-transition temperature〕
After the prepregs are laminated and molded, the storage elastic modulus (G ′) when the temperature is raised stepwise step by step using a rheometric RDA-700 or a viscoelasticity measuring device having equivalent performance. Measure at temperature. The temperature is raised at 5 ° C./step, and at each step, the temperature is held for 1 minute after the temperature is stabilized and then measured. The frequency is measured at 10 radians / second. The logarithmic value of G ′ is plotted against the temperature, and the temperature at the intersection of each tangent line of the glass elastic region and the transition region of the obtained G ′ curve is defined as the glass transition temperature (FIG. 1 shows a typical glass transition). A schematic graph of a temperature measurement example is shown).

(Ignition test)
After the prepreg is laminated and formed so as to have a thickness of 2 mm, an ignition test is performed in accordance with “Tetsunyu 81” of the Ministry of Land, Infrastructure, Transport and Tourism. The ignition test stipulated in Iron Fork 81 has the following contents.

  That is, hold a B5-size sample inclined at 45 °, place the fuel container on the cradle so that the center of the container is 25.4 mm vertically below the center of the lower surface of the sample, and add 0.5 cc of ethyl alcohol. Put it on and ignite it, and let it stand until the fuel is burned out. Judgment of flammability is made during and after the combustion of alcohol, igniting, igniting, smoking, and the state of flame are observed, and after combustion, afterflame, residual dust, carbonization, and deformation are examined.

  Judgment results are in descending order of ignition resistance. "Non-flammable", "Extremely flame retardant", "Flame retardant", "Slow flammability", "Flammable".

[Volume content of reinforcing fiber]
The volume content (V _f ) of the fiber reinforcement relative to the fiber reinforced resin composite material is the density of the fiber reinforced resin composite material (ρ _c ), the density of the fiber reinforcement (ρ _f ), and the curing of the cured matrix resin composition. From the density (ρ _r ) of the object, V _f (%) = {(ρ _c −ρ _r ) × 100 / (ρ _f −ρ _r )}.

[DSC curing degree]
The heating value (E ₀ ) of the matrix resin composition immediately after preparation and the residual heating value (E ₁ ) of the cured product obtained by curing the matrix resin composition were measured with a differential scanning calorimeter (DSC). The degree of cure (%) = {(E ₀ −E ₁ ) × 100 / E ₀ }.

[Weight reduction]
The weight (W ₁ ) at 50 ° C. and the weight (W ₂ ) between 300 ° C. and 350 ° C. of the cured product obtained by curing the matrix resin composition were measured with a thermogravimetric analyzer (TGA). %) = {(W ₁ −W ₂ ) × 100 / W ₁ }.

[Examples 1-9, Comparative Examples 1-17]
Hereinafter, specific configurations of the fiber-reinforced resin composite material, the matrix resin composition, and the prepreg of the present invention will be described based on examples and compared with comparative examples. In addition, each component used for the matrix resin composition of an Example and a comparative example is as showing the following abbreviation.

(1) Epoxy resin Ep828: manufactured by Japan Epoxy Resin Co., Ltd., liquid bisphenol A type epoxy resin “Epicoat 828”
AER4152: manufactured by Asahi Kasei Co., Ltd., epoxy resin having an oxazolidone ring in the molecule "Araldite AER4152"

(2) Curing agent, curing accelerator DCMU: Dichlorodimethylurea “DCMU99” manufactured by Hodogaya Chemical Co., Ltd.
PDMU: Ph.D. dimethylurea “OMICURE 94” manufactured by PTI Japan
TBDMU: Tobibisdimethylurea “OMICURE 24” manufactured by PTI Japan
Dicy: Dicyandiamide “Dicy7” manufactured by Japan Epoxy Resin Co., Ltd.
DDS: Diaminodiphenyl sulfone “Seika Cure S” manufactured by Wakayama Seika Co., Ltd.

(3) Metal oxide Magmic: manufactured by Kyowa Chemical Co., Ltd., magnesium oxide “magmic” thermal conductivity: 60 W / m · K, average particle size: 4 μm
Kyowa Mag 150: manufactured by Kyowa Chemical Co., Ltd., magnesium oxide “Kyowa Mug 150”, thermal conductivity: 60 W / m · K, average particle size: 15 μm
TiO ₂ : manufactured by Kojun Chemical Co., Ltd., titanium dioxide, “a-Al ₂ O ₃ ” thermal conductivity: 8.4 W / m · K, average particle size: 3 μm

(4) Thermoplastic resin YP70: manufactured by Tohto Kasei Co., Ltd., phenoxy resin “phenotote YP70”
Vinylec K: manufactured by Chisso, polyvinyl formal "Vinyleck K"

(5) Fiber reinforcement TR3110MS: Mitsubishi Rayon Co., Ltd., polyacrylonitrile-based carbon fiber TR30S (thermal conductivity: 7 W / m · K) plain weave cloth (weight per unit: 200 g / m ² )
LCP300: Arisawa Manufacturing Co., Ltd., glass fiber (E glass (thermal conductivity: 1 W / m · K)) plain-woven cloth (weight per unit: 310 g / m ² )

(Method for preparing resin composition)
The resin composition in the prepreg of the present invention was prepared by the following method.
That is, in Examples 1-2 and Examples 4-9, Comparative Examples 1-3, and Comparative Examples 6-17 using Dicy (dicyandiamide) as the curing agent and curing accelerator of component (C), bisphenol in liquid form 1.8 parts by mass of Dicy was blended with 3 parts by mass of Ep828, which is an A-type epoxy resin, and uniformly dispersed using three rolls to obtain a catalyst resin.

  Next, the remaining epoxy resin (A) shown in [Table 1] and [Table 2] and the thermoplastic resin (D) are blended and dissolved at 150 ° C. using a stirrer (C) A base resin was obtained by blending and dispersing the component metal oxides. The base resin was cooled to 60 ° C., and then the catalyst resin, the remaining component (B) curing agent and curing agent were blended and dispersed to obtain a matrix resin composition.

  In the method for preparing the resin compositions of Example 3 and Comparative Examples 4 to 5, the components (A) and (D) shown in [Table 1] and [Table 2] were dissolved at 150 ° C. A base resin was obtained by dispersing. After this base resin was cooled to 60 ° C., the component (B) was blended and dispersed to obtain a matrix resin composition.

(Preparation of cured product of resin composition and various evaluations)
A cured product of the resin composition was obtained by the following method. A part of the obtained resin composition was put in an aluminum dish and heat cured using a dryer at 100 ° C. for 5 hours to obtain a cured product. Using this cured product, the DSC curing degree and the mass reduction were measured by the test method described above. The obtained measurement results are shown in [Table 1] and [Table 2].

(Prepreg production)
A hot melt film (HMF) was produced from the resin composition using a film coater. Resin basis weight of the hot melt film, Examples 1 to 7 and Comparative Examples 1 to 11 66.5 g / m ^2, Example 8 40 g / m ^2, Example 9 90 g / m ^2, Comparative Example 12 100g / M ² , Comparative Example 13 is 27.5 g / m ² .

  The hot melt films obtained on both surfaces of various fiber reinforcements were bonded together and heat-pressed using a fusing press to prepare prepregs. In addition, as for the fiber reinforcement used for each prepreg, Comparative Example 11 used LCP300, Examples other than Comparative Example 11 and Comparative Example used TR3110MS.

(Various specimen preparation and various evaluations)
Each prepreg obtained as above was cut into a pattern of 300 × 300 mm. Examples 1-7, Comparative Examples 1-11 were 9 sheets, Example 8 was 11 sheets, Example 9 was 9 sheets, and Comparative Example 12 was 6 sheets. Thirteen sheets of Comparative Example 13 were laminated, and a fiber reinforced resin composite material having a thickness of 2 mm was obtained by vacuum back molding at 100 ° C. for 5 hours.

  The fiber reinforced resin composite material thus obtained was cut with the dimensions determined by the glass transition temperature measurement, the interlayer shear strength measurement, and the ignition test by Iron Transport No. 81, and various test pieces were produced. Using these various test pieces, the glass transition temperature measurement, the interlayer shear strength measurement, and the ignition test by Iron Fork 81 were conducted by the above-described test methods.

The volume content (Vf) of the reinforcing fiber is determined by measuring the density of the cured product of the obtained matrix resin composition and the density of the fiber reinforced resin composite material by the Archimedes method, and the density of the fiber reinforcing material is a catalog value (TR3110MS is , TR30S density: 1.8 g / cm ³ , LCP300 was E glass density: 2.5 g / cm ³ ), and the volume content (Vf) of the reinforcing fiber was calculated by the test method described above. Each measurement result is shown in [Table 1] and [Table 2].

  According to the above [Table 1] and [Table 2], it will be understood that the examples of the present invention have the following effects as compared with the comparative examples.

  As is clear from the comparison between Example 1 and Comparative Example 1, the ignition resistance is improved by blending magnesium oxide, which is a metal oxide, as the component (C) and phenoxy resin, which is the thermoplastic resin, as the component (D). It is possible to make it.

  As is clear from the comparison of Example 1, Comparative Example 2 and Comparative Example 3, when there is no metal oxide as the component (C) and no thermoplastic resin as the component (D), the ignition resistance is greatly reduced.

  As is clear from the comparison of Example 1, Example 2, Example 3, Comparative Example 4, Comparative Example 6 and Comparative Example 7, (B) component with respect to 100 parts by mass of the (A) component epoxy resin When the blending ratio of a certain curing agent and curing accelerator is 4 parts by mass or less, the mass decrease at 300 ° C. to 350 ° C. is 3% or less, and the determination of the ignition test by Iron Fork 81 is both nonflammable and ignition resistant. It turns out that is excellent. On the other hand, when the compounding ratio of the (A) component epoxy resin, 100 parts by mass of the (B) component curing agent and the curing accelerator exceeds 4 parts by mass, the mass decrease at 300 ° C. to 350 ° C. It can be seen that the ignition resistance is lower than 3% from the determination result of the ignition test by Iron Fork 81.

  As is clear from the comparison of Example 1, Example 2, Example 3, Example 9, Comparative Example 4 and Comparative Example 5, the curing agent as component (B), the curing accelerator is a urea compound alone, or When used in combination with dicyandiamide, the shear strength is 70 MPa or more, the glass transition temperature is 50 ° C. or more, and the DSC curing degree is 70% or more, which is excellent in mechanical properties, heat resistance, and curability. Further, when phenyldimethylurea (PDMU) or toluenedimethylurea (TBDMU) is used as the urea compound, these characteristics are further improved. On the other hand, those other than those in which the curing agent and curing accelerator as component (B) are urea compounds alone or in combination with dicyandiamide are inferior in mechanical properties, heat resistance and curability.

  As is clear from the comparison between Example 1 and Comparative Example 8, when the average particle diameter of the metal oxide as the component (C) is 15 μm, the shear strength is significantly reduced.

  As is clear from the comparison between Example 1 and Comparative Example 9, when the thermal conductivity of the metal oxide (C) is 8.4 W / m · K, from the determination result of the ignition test by Iron Transport No. 81 However, the ignition resistance decreases.

  As is clear from the comparison between Example 1 and Comparative Example 10, when the thermoplastic resin as the component (D) is polyvinyl formal, the ignition resistance is also lowered from the determination result of the ignition test by Iron Transport No. 81.

  As is clear from the comparison between Example 1 and Comparative Example 11, when the thermal conductivity of the fiber reinforcement is 1 W / m · K, the ignition resistance also decreases from the determination result of the ignition test by Iron Transport No. 81. .

  As is clear from the comparison of Example 1, Example 4, Example 5, Comparative Example 14 and Comparative Example 15, the epoxy resin of component (A), the metal oxide of component (C) with respect to 100 parts by mass In the case where the blending ratio is 3 parts by mass, the ignition resistance also decreases from the result of the ignition test by Iron Fork 81.

  Moreover, when the compounding ratio of the metal oxide of the component (C) is 45 parts by mass, the interlaminar shear strength is greatly reduced.

  As is clear from the comparison of Example 1, Example 6, Example 7, Comparative Example 16 and Comparative Example 17, the epoxy resin of component (A) and the thermoplastic resin of component (D) with respect to 100 parts by mass In the case where the blending ratio is 3 parts by mass, the ignition resistance also decreases from the result of the ignition test by Iron Fork 81. Further, when the blending ratio of the thermoplastic resin as the component (D) is 95 parts by mass, the interlaminar shear strength is significantly reduced.

  From the above results, it can be seen that Examples 1 to 9 are fiber reinforced resin composite materials that are superior in low-temperature curability and mechanical properties as compared with Comparative Examples 1 to 17 and that have an excellent balance in ignition resistance.

FIG. 1 is a graph in which logarithmic values of dynamic shear modulus G ′ of fiber reinforced resin composite materials manufactured in Examples and Comparative Examples of the present invention are plotted against temperature, and the fiber reinforced resin composite materials. 3 shows a drawing method for obtaining the glass transition temperature (Tg).

Claims (12)

A fiber reinforced resin composite material comprising a fiber reinforcement and a matrix resin composition;
Ministry of Land, Infrastructure, Transport and Tourism using a fiber composite material having a fiber reinforced resin composite material obtained by curing within 100 hours at 100 ° C. and having an interlayer shear strength of 60 MPa or more, a glass transition temperature of 50 ° C. or more, and a thickness of 2 mm A fiber reinforced resin composite material characterized in that the ignition test in accordance with No. 81 is nonflammable.   2. The fiber reinforced resin composite material according to claim 1, wherein the fiber reinforcement has a thermal conductivity of 5 W / m · K or more and a volume content of the fiber reinforcement relative to the fiber reinforced resin composite material is 45 to 70%.   The fiber reinforced resin composite material according to claim 1, wherein the interlayer shear strength is 70 MPa or more and the glass transition temperature is 80 ° C or more. The fiber reinforced resin composite material according to claim 1, wherein the matrix resin composition contains the following components (A), (B), (C), and (D) as essential components.
(A) Epoxy resin (B) Curing agent, curing accelerator (C) Metal oxide (D) Thermoplastic resin   The fiber reinforced resin composite material according to claim 1, wherein a DSC curing degree of a cured product obtained by curing the matrix resin composition within 100 hours at 100 ° C is 70% or more.   2. The fiber reinforcement according to claim 1, wherein a cured product obtained by curing the matrix resin composition at 100 ° C. within 5 hours has a mass reduction at 300 ° C. to 350 ° C. of 3% or less with respect to the mass at 50 ° C. 3. Resin composite material. The fiber-reinforced resin composite material according to claim 4, wherein a blending mass ratio of the components (A), (B), (C), and (D) is the following ratio.
(A) Epoxy resin: 100 parts by mass (B) Curing agent, curing accelerator: 4 parts by mass or less (C) Metal oxide: 5-40 parts by mass (D) Thermoplastic resin: 5-90 parts by mass   The fiber-reinforced resin composite material according to claim 7, wherein the component (B) is a urea compound alone or in combination with dicyandiamide.   The fiber-reinforced resin composite material according to claim 8, wherein the urea compound as the component (B) is phenyldimethylurea or toluenedimethylurea.   The fiber-reinforced resin composite material according to claim 7, wherein the thermal conductivity of the component (C) is 20 W / m · K or more and the average particle size is 10 µm or less.   The fiber-reinforced resin composite material according to claim 7, wherein the component (D) is a phenoxy resin.   A prepreg formed by impregnating a fiber reinforcing material with the matrix resin composition according to claim 4 or 7.

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