WO2011040567A1 - Matrix resin composition for fiber-reinforced plastic and fiber-reinforced plastic structure - Google Patents

Abstract

Disclosed is a fiber-reinforced plastic structure, comprising: fibers comprising one or more substances selected from a group consisting of glass, carbon, aramid, alumina, and boron; and a matrix resin composition with which the fibers are impregnated and bonded to one another. The matrix resin composition comprises: a matrix containing a bisphenol-based epoxy-containing resin and a curing agent; and particles containing one or more elastomers selected from a group consisting of polybutadiene rubber, styrene butadiene rubber, and butyl rubber, having an average particle diameter of from 0.01 to 0.5 μm, and primarily dispersed in the matrix by mixing with the matrix in an amount of from 1 to 50 parts by weight based on 100 parts by weight of the resin.

Description

Matrix resin composition for fiber reinforced plastic and fiber reinforced plastic structure

The present invention relates to a matrix resin composition that is applied to a fiber reinforced plastic structure to improve its shock absorption capacity and a fiber reinforced plastic structure having an improved shock absorption capacity.

An aircraft jet engine includes, as an example, a fan assembly, a compressor, a combustor, a turbine, and other assemblies. Energy is extracted from the combustion gas by the turbine to drive the fan assembly. A part of the outside air sucked in by the fan assembly is sent to the combustor, and the rest is pushed backward to contribute to thrust. All of these are housed and supported in a fan case.

∙ Aluminum and titanium alloys are applied to the fan case to reduce the weight of the jet engine. Aircraft are required to have high safety, and it is necessary to maintain the structure even when a large impact is applied. Naturally, sufficient toughness is considered in the application of such an alloy.

In recent years, attempts have been made to apply fiber reinforced plastic as a material for further weight reduction of aircraft. It is known that a fiber reinforced plastic can be applied to a part of a wing or a fuselage. Japanese Patent Publication No. 2006-305867 discloses related technology.

In applying a fiber reinforced plastic to a fan case, there are characteristics to be noted in addition to toughness in terms of safety, and according to studies by the inventors, one of them is shock absorbing ability. For example, when an internal member is damaged and collides with the fan case at a high speed, if the member escapes to the outside at a high speed, other structural members may be destroyed. That is, the fan case needs to prevent such a member from jumping out or to sufficiently absorb its kinetic energy. Fiber reinforced plastics are generally concerned about toughness and still have room for improvement in terms of impact absorption. The present invention has been made in view of such problems in order to expand the application of fiber-reinforced plastics.

According to the first aspect of the present invention, a matrix resin composition for fiber-reinforced plastics is a group consisting of a resin containing a resin containing a bisphenol-based epoxy and a curing agent, a polybutadiene rubber, a styrene butadiene rubber, and a butyl rubber. Particles containing one or more selected elastomers and having an average particle diameter of 0.01 to 0.5 μm, mixed as much as possible in a ratio of 1 to 50 parts by weight with respect to 100 parts by weight of the resin. Particles primarily dispersed in the matrix.

According to the second aspect of the present invention, the structure is made of a matrix resin that is impregnated with and bonded to fibers made of one or more substances selected from the group consisting of glass, carbon, aramid, alumina, and boron. A composition comprising a matrix containing a resin containing a bisphenol-based epoxy and a curing agent, and one or more elastomers selected from the group consisting of polybutadiene rubber, styrene butadiene rubber and butyl rubber, and having an average particle size of 0 And a matrix resin composition containing particles that are mixed in a ratio of 1 to 50 parts by weight with respect to 100 parts by weight of the resin and primarily dispersed in the matrix.

FIG. 1 is a partial cross-sectional plan view of a fan case of a jet engine according to an embodiment of the present invention. FIG. 2 is a flying object impact test result regarding the fiber-reinforced plastic structure according to the present embodiment, and shows the relationship between the speed immediately after the penetration and the speed immediately before the collision. FIG. 3 also shows the flying object impact test result, showing the relationship of the absorbed energy to the kinetic energy just before the collision.

Hereinafter, embodiments of the present invention will be described with reference to the drawings.

According to the present embodiment, the matrix resin composition for fiber reinforced plastic is composed of a matrix made of an appropriate resin and a curing agent, and in the matrix, appropriate particles for improving the impact absorbing ability of the fiber reinforced plastic are primarily dispersed. is doing. Throughout this specification and the appended claims, the term “primary dispersion” is used in its ordinary sense as widely recognized by those skilled in the art. It should not be construed as introducing a definition different from the usual meaning, but it means that the particles are dispersed in the medium in the state of primary particles, i.e. the individual particles are independent of each other without agglomeration. It can be explained that it is.

As the resin, a resin (component A) having high strength and small shrinkage upon curing is advantageous. Examples of such a resin include bisphenol epoxy resins containing bisphenol A or bisphenol F, but other resins may be used.

The additive component (component B) may be included in the resin. For example, a modified epoxy resin may be added for the purpose of improving heat resistance. Examples of the modified epoxy resin include a bifunctional epoxy resin having a naphthalene skeleton and a phenoxy resin having a hydroxyl group in the molecule. Component B may be a mixture of two or more modified epoxy resins. From the viewpoint of heat resistance, addition of 0% by weight or more of the modified epoxy resin is preferable, and addition of 2% by weight or more is more preferable with respect to the whole resin. However, from the viewpoint of toughness, the addition of 80% by weight or less is preferable, the addition of 50% by weight or less is more preferable, and the addition of 30% by weight or less is more preferable.

Similarly, for the purpose of improving the heat resistance, other components (component C) may be added instead of or in addition to the modified epoxy resin. As such an example, a polyfunctional epoxy resin can be mentioned, and specific examples thereof include, for example, triglycidylparaaminophenol as a trifunctional group, tetraglycidylparaaminomethane as a tetrafunctional group, and a novolac type. An epoxy resin can be illustrated. Alternatively, Component C may be a mixture of two or more of these. From the viewpoint of heat resistance, addition of 0% by weight or more of the polyfunctional epoxy resin is preferable, and addition of 2% by weight or more is more preferable with respect to the whole resin. However, from the viewpoint of toughness, the addition of 80% by weight or less is preferable, the addition of 50% by weight or less is more preferable, and the addition of 30% by weight or less is more preferable.

Component A is substantially the remainder excluding components B and C in the entire resin. From the viewpoint of imparting sufficient flexibility to the fiber reinforced plastic precursor before curing, the component A is preferably 20% by weight or more based on the entire resin.

A curing agent (component D) is usually added to the epoxy resin. As a curing agent suitable for the epoxy resin, as is generally known, an amine curing agent, an acid anhydride curing agent, or a phenol curing agent can be used. Or a catalyst hardening | curing agent can be utilized and an imidazole and a boron trichloride type | system | group amine complex are mentioned as such an example. Alternatively, a mixture of two or more of these may be used. Among these, amine-based curing agents such as benzenediamine, diaminodimethylmethane or methanephenylenediamine are advantageous from the viewpoint of toughness and impact absorption ability. Usually, a hardening | curing agent is added so that it may become an equivalent with respect to the epoxy group in an epoxy resin. A small amount of salicylic acid or boron trifluoride ethylamine complex may be added for the purpose of adjusting the reaction rate during curing.

As the particles for enhancing the impact absorbing ability of the fiber reinforced plastic, an elastomer having a deformability larger than that of the resin is suitable. Such particles absorb the applied impact energy by deformation, thereby improving the toughness of the fiber reinforced plastic and taking away the kinetic energy from the impactor and reducing its velocity. Examples of such particles include polybutadiene rubber, styrene butadiene rubber, and butyl rubber. Alternatively, two or more of these may be applied.

Alternatively, particles having a so-called core-shell structure in which one or more kinds of these elastomers are used as a core and each core is included in a shell layer can be applied. Vinyl chloride can be applied to the shell layer, but acrylic resin can be applied instead of or together with this.

From the viewpoint of ease of handling, the particle diameter is preferably 0.01 μm or more, more preferably 0.05 μm or more. On the other hand, from the viewpoint of promoting uniform dispersion, it is advantageous that the particle diameter is small, and the particle diameter is preferably 0.5 μm or less, more preferably 0.2 μm or less. Of course, other particle diameters can be used if possible.

It is preferable that the elastomer in the particles has an appropriate ratio with respect to the resin. That is, if the elastomer is 1 part by weight or more with respect to 100 parts by weight of the resin, improvement in impact absorbing ability can be expected, and more preferably 2 parts by weight or more. If the ratio of the elastomer is excessive, there will be a problem in dispersibility, so it is 50 parts by weight or less, more preferably 30 parts by weight or less, and even more preferably 25 parts by weight or less. However, a mixing ratio exceeding these ranges may be used if possible.

If the particles are aggregated in the matrix, the distribution of the particles is biased, and the particles are preferentially broken at a dense portion, and as a result, sufficient toughness and shock absorbing ability may not be obtained. Therefore, in order to obtain a sufficient shock absorption capacity, it is preferable that the particles are primarily dispersed.

The particles containing the elastomer can be obtained by either wet or dry methods. However, when placed in a dry state, the particles aggregate with each other due to the inherent van der Waals force and electrostatic attraction, and the aggregated particles are difficult to be primarily dispersed. Therefore, it is preferable to introduce and disperse the particles into the matrix without passing through a dry state. For example, particles obtained in the form of an aqueous latex are mixed with an appropriate organic solvent, and the aqueous phase is separated and removed to obtain particles that are primarily dispersed in the organic solvent. This is mixed with the resin, and the organic solvent is separated and removed if necessary. An organic solvent that can be mixed with an aqueous phase can be used. Such organic solvents include alcohols such as methanol and ethanol, ketones such as acetone and methyl ethyl ketone, ethers such as diethyl ether and dioxane, esters such as methyl acetate and ethyl acetate, aromatic hydrocarbons such as toluene, and chloroform. Examples thereof include halogenated hydrocarbons. Furthermore, after mixing with an organic solvent that can be mixed with the aqueous phase, the aqueous phase may be separated and removed after further mixing with an organic solvent that is not mixed with the aqueous phase. Alternatively, the primary dispersion may be by other methods if possible.

The mixing of each component in the resin and the mixing of the particles into the resin may be performed in any order. That is, after mixing each component in resin, you may mix particle | grains in this resin. Alternatively, particles may be mixed in advance with any of the above components, for example, an epoxy resin, and then the B and C components and the curing agent may be mixed therewith. Further, the mixing ratio may be adjusted by further mixing an epoxy resin with an epoxy resin in which particles are previously mixed. The above mixing ratio is the resulting mixing ratio.

The matrix resin composition prepared as described above is impregnated into an appropriate bundle of reinforcing fibers. The reinforcing fiber may be any of glass, carbon, aramid, alumina, and boron, or other appropriate fiber.

Reinforcing fibers consist of long fibers oriented in one direction, a set of long fibers oriented and laminated in multiple directions, a set of long fibers laminated and stitched together, a two-dimensional fabric of long fibers, Any form of a three-dimensional textile fabric may be used. Further, short fibers may be randomly dispersed in the matrix resin composition. A fiber-reinforced plastic precursor is constituted by the reinforcing fiber and the matrix resin composition impregnated therein.

The fiber reinforced plastic precursor is formed into a target structure by an appropriate means such as a press. After molding or simultaneously with molding, the fiber reinforced plastic precursor is pressurized and heated by means such as autoclave, and the resin is cured. The pressurization is, for example, 0.5 to 1 MPa, but is not necessarily limited thereto. The temperature rise is, for example, about 100 to 200 ° C. for several hours, but is not limited to this. The matrix resin composition bonds the fibers to each other by curing, thereby completing the fiber-reinforced plastic structure.

In order to verify the effect, impact tests were conducted on the following examples.

The following epoxy resin was prepared as component A.

(A-1) Bisphenol F type epoxy resin generally available from Mitsubishi Chemical Corporation under the trade name jer806 (A-2) Same jer807: Bisphenol A type epoxy resin (A-3) Same jer1001: Solid bisphenol A type Epoxy resin (A-4) Similarly jer4004P: Solid bisphenol F type epoxy resin As component B, the following modified epoxy resin was prepared.

(B) Naphthalene skeleton-containing epoxy resin generally available from DIC Corporation under the trade name of HP4032 As Component C, the following polyfunctional epoxy resin was prepared.

(C) Tetrafunctional epoxy resin generally available from Mitsubishi Chemical Corporation under the trade name of jer604 As Component D, the following curing agent was prepared.

(D-1) Amine-based curing agent generally available from Mitsubishi Chemical Corporation under the trade name JerW (D-2) Diaminodiphenylmethane (DDM) generally available from Mitsubishi Chemical Corporation under the trade name EK150D
As Component E, the following particles were prepared. In these, the particles are preliminarily dispersed in the epoxy resin in advance.

(E-1) Bisphenol A type epoxy resin containing 25 wt% styrene butadiene rubber particles generally available from Kaneka Corporation (E-2) Containing 25 wt% polybutadiene rubber particles generally available from Kaneka Corporation Bisphenol F type epoxy resin (E-3) Bisphenol A type epoxy resin containing 25% by weight of polybutadiene rubber particles generally available from Kaneka Corporation In addition, Hitachi Chemical Co., Ltd. under the trade name MHAC-P as a curing agent Generally available from ADEKA Corporation under the trade name of EHC-30 as a commonly available acid anhydride curing agent (methyl-3,6-endomethylene-1,2,3,6-tetrahydrophthalic anhydride) HUNTSMAN Co., Ltd. under the trade name DY9577 as a latent tertiary curing agent Generally it was prepared and commonly available 2-ethyl-4-methylimidazole from Shikoku Chemicals Corporation under the trade name boron trichloride amine complexes and 2E4MZ available from the company.

The above components were mixed at the mixing ratios listed in Table 1 and Table 2, respectively, to prepare 17 types of matrix resin composition samples T-1 to T-12 and C-1 to C-5. Each sample was impregnated by a solvent method into a carbon fiber sheet (generally available from Toray Industries, Inc. under the trade name T800S-24K) so that the resin content was 36% by mass. Each of the carbon fiber sheets impregnated with the sample was further laminated to obtain a fiber reinforced plastic precursor. The laminated layers are four layers, and the layers are oriented so that the orientations of the fibers are different from each other. The orientations of the layers are 0 °, 90 °, 45 °, and −45 ° with respect to the reference direction. Hereinafter, such a lamination method is referred to as pseudo-isotropic lamination.

In order to cure the pseudo-isotropic laminated fiber reinforced plastic precursor sample, each was introduced into an autoclave, applied with 0.6 MPa, heated at 100 ° C. for 2 hours, and subsequently heated at 120 ° C. for 1 hour, Furthermore, it heated at 180 degreeC continuously for 6 hours. The dimension of the sample after curing is 200 mm long × 150 mm wide × 5 mm thick.

Using a hunting gun, a titanium bullet with a diameter of 10 mm and a length of 12 mm was fired at 220 m / sec perpendicularly to the surface of these specimens, and shot with a high-speed camera before and after the impact. did. By measuring the position of the bullet from the image, the velocity immediately before and after the collision was calculated. Further, the impact absorption rate was calculated from the calculated speed by the following formula.

Formula 1

As understood from the above equation, the value of the shock absorption rate increases as the speed after penetration is smaller than the speed before the collision (the degree of shock absorption is large).

The measurement results are shown in Tables 1 and 2.

Samples T-1 to T-12 containing particles containing primarily dispersed elastomer exhibit a higher impact absorption rate than samples C-1 to C-5 containing no particles. That is, they are excellent in terms of impact absorbing ability. Samples T-1 to T-3, T-7 to T-9, T-11, T-12 and C-1 containing an amine-based curing agent are compared with samples not containing an amine-based curing agent. The impact absorption rate tends to be high.

Further shock absorption tests were performed on the samples T-3, T-4, C-1, C-4 and the sample C-6 having the following composition.

C-6: Tetraglycidyldiaminodiphenylmethane (available from Sumitomo Chemical Co., Ltd. under the trade name ELM434) + 10 parts by weight of bisphenol F type epoxy resin (available from DIC Corporation under the trade name of Epicron 380) +4 4'-diaminodiphenylsulfone (available from Sumitomo Chemical Co., Ltd. under the trade name of Sumicure S) + 15 parts by weight of polyethersulfone (available from ICI Corporation under the trade name of 5003P) −3, T-4, C-1, C-4, C-6 are all common, the length is 200 mm × width 200 mm × thickness 5 mm, and the orientation of each layer is 0 °, 45 °, 0 with respect to the reference direction, respectively. °, -45 °.

Using a gas gun driven by pressurized gas, a cylindrical steel flying object having a diameter of 13 mm and a length of 13 mm (mass: about 13.3 g) was shot into these samples perpendicularly to the surface, and the flying object was I shot it with a high-speed camera before and after the collision. Unlike the above test, each test was performed at various flying object speeds. By measuring the position of the bullet from the image, the velocity immediately before and after the collision was calculated. Further, the kinetic energy of the flying object just before the collision and the energy absorbed by the sample were calculated from the calculated speed. Table 3 shows the measurement results.

The measurement results of speed are shown in FIG. In any sample, if the velocity Vp immediately before the collision is somewhat small, the flying object cannot penetrate the sample (the velocity Vr immediately after penetration is 0). If the velocity Vp is large to some extent, the flying object penetrates the sample, and the velocity Vr immediately after the penetration is measured. Above the limit speed, Vr increases sharply with Vp, so this limit speed can be estimated from the intersection of the Vr / Vp graph and Vr = 0. The critical speed is about 200 m / s for T-3, about 180 m / s for T-4, and about 150 m / s for C-4. That is, the samples T-3 and T-4 containing the particles containing the primary dispersed elastomer have higher performance to prevent the flying object from penetrating than the sample C-4 containing no particles.

Fig. 3 shows the measurement results of kinetic energy. The horizontal axis of the graph is the kinetic energy Ei of the flying object immediately before the collision, and the vertical axis is the energy Eab absorbed by the sample. Since all of the kinetic energy is absorbed by the sample below the critical speed, the plotted points are arranged on a straight line going up to the right where Ei = Eab. The group of points separated to the right of this straight line is the case where the flying object penetrates the sample. When the flying object penetrates, the energy Eab absorbed by the sample does not depend much on the kinetic energy Ei immediately before the collision, and is about 300 J for T-3, about 230 J for T-4, C-4 And in the case of C-6, it is about 180J. That is, the samples T-3 and T-4 containing the particles containing the primary dispersed elastomer are more capable of absorbing the kinetic energy of the flying object, that is, the shock absorbing ability than the samples C-4 and C-6 containing no particles. Is expensive.

The matrix resin composition and the fiber reinforced plastic of the present embodiment are lightweight and are suitable for structures that require toughness and shock absorption capability. An example of such a structure is the fan case of the jet engine shown in FIG. Of course, the application is not limited to this, and the fuel tank and the body of various transportation vehicles are widely used.

Although the present invention has been described with reference to preferred embodiments, the present invention is not limited to the above embodiments. Based on the above disclosure, a person having ordinary skill in the art can implement the present invention by modifying or modifying the embodiment.

Supplied with fiber reinforced plastic with excellent shock absorption capability.

Claims (10)

1. A matrix containing a resin containing a bisphenol-based epoxy and a curing agent;
   Particles containing one or more elastomers selected from the group consisting of polybutadiene rubber, styrene butadiene rubber and butyl rubber and having an average particle diameter of 0.01 to 0.5 μm, and 1 per 100 parts by weight of the resin Particles mixed as much as possible in a proportion of 50 parts by weight and primarily dispersed in the matrix;
   A matrix resin composition for fiber-reinforced plastics.
2. 2. The matrix resin composition according to claim 1, wherein the particle includes a shell made of one or more resins selected from the group consisting of vinyl chloride and acrylic resin, surrounding the elastomer.
3. 2. The matrix resin composition according to claim 1, wherein the particles are 2 to 30 parts by weight with respect to 100 parts by weight of the resin.
4. 2. The matrix resin composition according to claim 1, wherein the particles are 2.5 to 15 parts by weight with respect to 100 parts by weight of the resin.
5. 2. The matrix resin composition according to claim 1, wherein the matrix includes a bifunctional epoxy resin having a naphthalene skeleton, a phenoxy resin having a hydroxyl group in the molecule, triglycidylparaaminophenol, tetraglycidylparaaminomethane, and a novolac type epoxy resin. Any one selected from the group consisting of more than 0 wt% and not more than 30 wt% with respect to the entire matrix is further included.
6. A fiber made of one or more substances selected from the group consisting of glass, carbon, aramid, alumina and boron;
   A matrix resin composition impregnated and bonded to the fibers,
   A matrix containing a resin containing a bisphenol-based epoxy and a curing agent;
   It contains one or more elastomers selected from the group consisting of polybutadiene rubber, styrene butadiene rubber and butyl rubber, has an average particle diameter of 0.01 to 0.5 μm, and 1 to 50 parts by weight with respect to 100 parts by weight of the resin A matrix resin composition comprising particles dispersed in the matrix and primarily dispersed in the matrix,
   A structure with
7. 7. The structure according to claim 6, wherein the particle includes a shell made of one or more resins selected from the group consisting of vinyl chloride and an acrylic resin, surrounding the elastomer.
8. 7. The structure according to claim 6, wherein the particles are 2 to 30 parts by weight with respect to 100 parts by weight of the resin.
9. 7. The structure according to claim 6, wherein the particles are 2.5 to 15 parts by weight with respect to 100 parts by weight of the resin.
10. 7. The structure according to claim 6, wherein the matrix is a bifunctional epoxy resin having a naphthalene skeleton, a phenoxy resin having a hydroxyl group in the molecule, triglycidyl paraaminophenol, tetraglycidyl paraaminomethane, and a novolac type epoxy. Any one selected from the group consisting of resins is further included in an amount of more than 0% by weight and not more than 30% by weight based on the entire matrix.

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