JP2020138405A - Unidirectional fiber reinforced composite material - Google Patents

Abstract

To provide a unidirectional fiber reinforced composite material having two or more characteristics.SOLUTION: In a unidirectional fiber reinforced composite material 1 formed by aligning a plurality of continuous fibers 3 as reinforcing fibers in one direction in a matrix 2, two or more kinds of resin compositions 2a and 2b each having a different component composition form a matrix 2. In a cross-section perpendicular to the longitudinal direction of the continuous fibers 3, a region configured by one resin composition 2a and a region configured by the other resin composition 2b are mutually adjacent to each other, and each resin composition 2a or 2b continues in the longitudinal direction of the continuous fibers 3.SELECTED DRAWING: Figure 1

Description

The present invention relates to a unidirectional fiber reinforced composite in which a plurality of continuous fibers are arranged in one direction in a matrix.

A unidirectional fiber reinforced composite material using continuous fibers as a reinforcing material is generally produced by impregnating a reinforcing fiber bundle such as carbon fiber with a thermoplastic resin (see Patent Documents 1 and 2). For example, in the method described in Patent Document 1, a fiber reinforced plastic tape having a predetermined width is obtained by coating the periphery of the reinforcing fiber bundle with a matrix resin in a crosshead mold and then opening the fibers. Further, in the method for producing a fiber-reinforced tape described in Patent Document 2, a reinforcing fiber bundle in which a plurality of fibers are arranged in a layer is used, and the fiber is reinforced by passing through a dipping die in which a molten matrix resin is stored. The matrix resin is impregnated between the single fibers constituting the fiber bundle.

Further, conventionally, a plurality of reinforcing fibers arranged in a tape or a sheet shape in one direction and a plurality of thermoplastic fibers arranged in a tape or a sheet shape in the same direction are laminated and heated / pressurized to form a tape or a sheet. A method for obtaining a sheet-shaped fiber base material has also been proposed (see Patent Document 3). In the fiber base material described in Patent Document 3, the reinforcing fibers and the thermoplastic fibers are arranged in one direction, and the single fibers and the thermoplastic of the reinforcing fibers are formed at least at the laminated interface in the cross section perpendicular to the fiber arrangement direction. The cross sections of the single fibers of the fibers are mixed and distributed, and at least a part of the cross sections of the thermoplastic fibers are fused between the cross sections of the reinforcing fibers.

Japanese Unexamined Patent Publication No. 2013-104056 International Publication No. 2015/046290 Japanese Unexamined Patent Publication No. 2015-017343

However, the method of impregnating the reinforcing fiber bundle with the matrix resin as described in Patent Documents 1 and 2 makes it difficult to impart a plurality of properties to the unidirectional fiber reinforced composite material, and the reinforcing material to be used. The degree of freedom is low because the fineness of the material and the size and strength of the composite material that can be manufactured are limited. On the other hand, in the method of laminating the reinforcing fiber and the thermoplastic fiber in the form of a tape or a sheet described in Patent Document 3, since the processing is performed at high temperature and high pressure, the reinforcing fiber having a high decomposition temperature and less likely to cause temperature deterioration can be obtained. It is necessary to use it, and it is difficult to apply it to general-purpose resins. For this reason, conventional unidirectional fiber reinforced composites have limited applications and lack versatility.

Therefore, an object of the present invention is to provide a unidirectional fiber reinforced composite material having two or more characteristics.

The unidirectional fiber reinforced composite material according to the present invention is a unidirectional fiber reinforced composite material in which a plurality of continuous fibers are arranged in one direction in a matrix, and the matrix has two or more kinds having different component compositions. It is composed of a resin composition, and in a cross section perpendicular to the longitudinal direction of the continuous fiber, a region composed of one resin composition and a region composed of another resin composition exist adjacent to each other, and each of them The resin composition exists continuously in the longitudinal direction of the continuous fibers.
This unidirectional fiber-reinforced composite material has a sea-island cross-sectional structure in which a plurality of island components are scattered in the sea component, and is formed by using at least two or more kinds of composite fibers in which the component compositions of the sea components are different from each other. In that case, the matrix is composed of the sea component of each composite fiber, and the continuous fiber is composed of the island component of each composite fiber.
As each composite fiber forming the unidirectional fiber reinforced composite material, for example, the sea component is composed of a thermoplastic resin composition, and the island component is composed of a thermoplastic resin composition having a melting point higher than that of the sea component. Can be used.
On at least one surface of the unidirectional fiber-reinforced composite material of the present invention, the interface portion between the one resin composition and the other resin composition is notched continuously or discontinuously in the longitudinal direction. A notch may be formed.
Further, the unidirectional fiber reinforced composite material of the present invention is, for example, a long sheet or tape.

According to the present invention, since the matrix is composed of two or more resin compositions having different component compositions, it is possible to impart two or more characteristics to the unidirectional fiber-reinforced composite material.

A and B are views schematically showing the fiber-reinforced composite material of the first embodiment of the present invention, A is a plan view, and B is an enlarged cross-sectional view taken along line xx shown in A. It is a conceptual diagram which shows the method of manufacturing the fiber-reinforced composite material 1 shown in FIG. A and B are cross-sectional views showing structural examples of composite fibers used in the production of the fiber-reinforced composite material 1. A and B are views schematically showing the fiber-reinforced composite material of the second embodiment of the present invention, A is a plan view, and B is an enlarged sectional view taken along line yy shown in A.

Hereinafter, embodiments for carrying out the present invention will be described in detail with reference to the accompanying drawings. The present invention is not limited to the embodiments described below.

(First Embodiment)
First, the fiber-reinforced composite material according to the first embodiment of the present invention will be described. 1A and 1B are views schematically showing the fiber-reinforced composite material of the present embodiment, FIG. 1A is a plan view, and FIG. 1B is an enlarged cross-sectional view taken along line xx shown in FIG. 1A. As shown in FIGS. 1A and 1B, the fiber-reinforced composite material 1 of the present embodiment is a unidirectional fiber-reinforced composite material in which continuous fibers 3 are embedded in a matrix 2 in a unidirectional arrangement.

[Matrix 2]
The matrix 2 is composed of two or more kinds of resin compositions 2a and 2b having different component compositions and exhibiting different characteristics from each other. By forming the matrix 2 with a plurality of resin compositions having different properties in this way, it is possible to impart two or more properties to the fiber-reinforced composite material 1. Here, the characteristics (having the resin compositions 2a and 2b) imparted to the fiber-reinforced composite material 1 include color (multicoloring), heat (flame retardant / delayed flame), and aroma (deodorant / deodorant). Fragrance), electricity (conductive / non-conductive / semi-conductive), fungus (antibacterial / bactericidal), sound (soundproof / soundproof), various physical properties (texture / hardness / toughness / slipperiness / tack) (Resistance, chemical resistance, compatibility) and the like.

For the resin compositions 2a and 2b, a functional resin having the desired characteristics may be used, but a material having the desired characteristics may be separately added to the resin. Examples of materials to be blended in the resin for imparting properties include pigments, pigments, deodorants, fragrances, antibacterial agents, bactericides, sound insulating materials, sound absorbing materials, conductive materials and the like.

The two or more properties imparted to the fiber-reinforced composite material 1 are not particularly limited, and may be either contradictory properties or similar properties. For example, by blending pigments of different colors into the resin compositions 2a and 2b, a multicolored fiber-reinforced composite material 1 can be obtained. Further, if the deodorant is blended in the resin composition 2a and the disinfectant is blended in the resin composition 2b, the fiber-reinforced composite material 1 can be provided with the deodorant function and the bactericidal function.

Further, the resin compositions 2a and 2b may be imparted with contradictory properties such as flame retardancy or slow flame and flammability, water absorption and oil absorption, and water repellency and oil repellency, respectively. As a result, when different performances are mixed, it is possible to obtain a contrasting effect or a synergistic effect in which one or both performances are enhanced, or a suppressing effect in which one or both performances are weakened. For example, when a resin composition having thermal expansion property and a resin composition having negative thermal expansion property (heat shrinkage property) are combined, a fiber-reinforced composite material 1 which is hard to be thermally deformed can be obtained.

The resins constituting the resin compositions 2a and 2b are not particularly limited, but thermoplastic resins are preferable from the viewpoint of processability, and among them, polyolefin-based resins that can be molded at a relatively low temperature are preferable. Specifically, the resin compositions 2a and 2b include low-density polyethylene, linear low-density polyethylene, high-density polyethylene, ethylene-based resins such as ethylene vinyl acetate, α-olefins such as ethylene and butene, and propylene. Random or block copolymer polypropylene, which is a primary or ternary copolymer, can be used. Among these polyolefin-based resins, low-density polyethylene, linear low-density polyethylene, and high-density polyethylene are particularly preferable because they have a clear melting point and exhibit a sharp melting behavior with respect to temperature.

In the fiber-reinforced composite material 1 of the present embodiment, the resin compositions 2a and 2b described above are present adjacent to each other in a cross section perpendicular to the longitudinal direction L of the continuous fiber 3 shown in FIG. 1B, and are continuous. The fibers 3 are arranged so as to exist continuously in the longitudinal direction L. Note that FIG. 1B shows an example in which the resin composition 2a and the resin composition 2b are alternately arranged in the width direction, but the present invention is not limited to this, and the component compositions are different from each other. Two or more resin compositions exhibiting different properties may be laminated in the thickness direction, and may be alternately or in a specific repeating pattern in both the width direction and the thickness direction, for example, in a checkered pattern. It may be arranged by.

[Continuous fiber 3]
The continuous fiber 3 is a reinforcing material, and for example, in addition to synthetic fibers such as polyester fibers, natural fibers such as cotton, metal fibers such as steel fibers, glass fibers, carbon fibers, stone ink fibers, ceramic fibers and the like can be used. , The material is not particularly limited. Further, for the fiber reinforced composite material 1 of the present embodiment, several types of continuous fibers 3 having different types and characteristics can be used.

As the continuous fiber 3 used in the fiber-reinforced composite material 1 of the present embodiment, among the various fibrous reinforcing materials described above, synthetic fibers are particularly preferable from the viewpoint of manufacturing. In that case, from the viewpoint of production stability, it is preferable to use the synthetic fiber used for the fiber-reinforced composite material 1 having a melting point higher than that of the resin compositions 2a and 2b (matrix 2) by 20 ° C. or more. For example, when a polyolefin-based resin is used as the resin compositions 2a and 2b, the continuous fiber 3 can be a polyolefin-based fiber, an aramid fiber, a polyamide fiber, a polyester fiber, an acrylic fiber, a rayon, or the like.

[form]
The fiber-reinforced composite material 1 of the present embodiment is, for example, a long sheet or tape having a thickness t of 5 mm or less, preferably 3 mm or less. The width w and the length of the fiber-reinforced composite material 1 of the present embodiment are not particularly limited, and can be appropriately set according to the application and purpose.

[Production method]
Next, a method for producing the fiber-reinforced composite material 1 of the present embodiment will be described. FIG. 2 is a conceptual diagram showing a method for producing the fiber-reinforced composite material 1 of the present embodiment, and FIGS. 3A and 3B are cross-sectional views showing a structural example of the composite fiber used in the production by the method shown in FIG. Is.

The fiber-reinforced composite material 1 of the present embodiment can be manufactured, for example, by producing two or more types of composite fibers 4a and 4b having different characteristics using a plurality of extruders and integrating them. Specifically, a roving 5a in which the composite fiber 4a is wound in a cylindrical shape and a roving 5a in which the composite fiber 4b is wound in a cylindrical shape are arranged on a bobbin stand, and the composite fiber 4a and the composite fiber 4b alternate with each other. Unwind so that it is arranged in. The unwound composite fibers 4a and 4b are converged by the slit 6, then heated while being pressed by the heating roller 7, formed into a tape shape, and wound by the winding roller 8.

(Composite fibers 4a, 4b)
The composite fibers 4a and 4b used in the fiber-reinforced composite material 1 of the present embodiment have a sea-island cross-sectional structure in which a plurality of islands 13 components are scattered in the sea components 12 as shown in FIGS. 3A and 3B, and at least the sea. The composition of the component 12 may be different from each other. In the fiber-reinforced composite material 1 produced by using the composite fibers 4a and 4b having the sea-island cross-sectional structure, the continuous fibers 3 are composed of the island components 13 of the composite fibers 4a and 4b. Further, since the matrix 2 of the fiber-reinforced composite material 1 is composed of the sea components 12 of the composite fibers 4a and 4b, it is composed of two or more kinds of resin compositions having different component compositions.

The cross-sectional area ratio of the island component 13 and the sea component 12 in the composite fibers 4a and 4b is to secure the adhesive force between the composite fibers 4a and 4b at the time of forming the fiber reinforced composite material 1 and to secure the strength of each continuous fiber 3. , Island component / sea component = 20/80 to 80/20 is preferable. The composite fibers 4a and 4b used in the fiber-reinforced composite material 1 are not limited to those having a circular cross section shown in FIG. 3A, and those having a flat elliptical cross section shown in FIG. 3B can be used. Further, in the composite fibers 4a and 4b, from the viewpoint of production stability, the sea component 12 is a thermoplastic resin composition, and the island component 13 is a thermoplastic resin composition having a melting point higher than that of the sea component 12 by 20 ° C. or more. Is preferable.

As described in detail above, the fiber-reinforced composite material of the present embodiment forms a matrix with two or more kinds of resin compositions having different component compositions and different characteristics, and has a cross section perpendicular to the longitudinal direction of continuous fibers. Since the region composed of the resin composition of No. 1 and the region composed of other resin compositions exist adjacent to each other, and each resin composition exists continuously in the longitudinal direction of the continuous fiber 3. Two or more properties can be imparted to the unidirectional fiber reinforced composite material.

(Second Embodiment)
Next, the fiber-reinforced composite material according to the second embodiment of the present invention will be described. 4A and 4B are views schematically showing the fiber-reinforced composite material of the present embodiment, FIG. 4A is a plan view, and FIG. 4B is an enlarged cross-sectional view taken along the line yy shown in FIG. 4A. In the fiber-reinforced composite materials shown in FIGS. 4A and 4B, the same components as those of the fiber-reinforced composite material 1 shown in FIGS. 1A and 1B are designated by the same reference numerals, and detailed description thereof will be omitted.

As shown in FIGS. 4A and 4B, the fiber-reinforced composite material 10 of the present embodiment is continuous in the longitudinal direction L at the interface portion between one resin composition 2a and the other resin composition 2b on at least one surface. The notch 11 or the notch is formed discontinuously. The shape of the notch and the notch formed on the surface of the fiber-reinforced composite material 10 of the present embodiment is not particularly limited, and may be a shape that can be separated / divided for each characteristic (resin composition 2a, 2b). Just do it.

Specifically, holes, U-shaped or V-shaped grooves, stepped grooves, perforations, and the like can be applied, but a straight groove shape is preferable from the viewpoint of achieving both tear strength and ease of division. Such notches and cuts can be shaped using, for example, a groove roller or a press die.

Further, in order to prevent the fiber reinforced composite material 10 from being divided at an unintended place during work, the depth of the notch and the notch is set with respect to the thickness of the portion where the notch or the notch is not formed. , 0.1 to 0.6, and more preferably 0.2 to 0.4 in terms of the balance between the ease of splitting or tearing and the strength of the tape.

As described in detail above, the fiber-reinforced composite material of the present embodiment is provided with a notch or a notch at the interface portion between one resin composition 2a and the other resin composition 2b, so that each characteristic can be easily obtained. Can be subdivided or subdivided. The composition and effect of the fiber-reinforced composite material of the present embodiment other than the above are the same as those of the first embodiment described above.

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

<Example 1>
As Example 1 of the present invention, the unidirectional fiber reinforced composite material 1 of the first embodiment shown in FIG. 1 was produced by the method shown in FIG. 2 using the composite fiber having the structure shown in FIG. 3B. First, the island component 13 is composed of polypropylene and the sea component 12 is composed of high-density polyethylene, the cross-sectional area ratio of each component is island component: sea component = 65:35, the fineness is 1850 dtex, and the composite is colored white. The roving 5a of the fiber 4a and the roving 5b of the composite fiber 4b, which is the same as the composite fiber 4a except that it is colored red, were prepared and placed on the bobbin stand.

Then, eight white-colored composite fibers 4a and seven red-colored composite fibers 4b are fed out from the bobbin stand, and the composite fibers 4a and the composite fibers 4b are alternately arranged in a comb shape. It passed through the slit 6 and converged. Next, the composite fiber bundles 4a and 4b were fused while being taken up at a linear speed of 2.8 m / min and pressurized under the condition of a linear pressure of 5 kg / m ² using a heating roller 7 heated to 130 ° C. Then, by cooling and solidifying, a unidirectional fiber reinforced tape having a thickness (average value of 5 points) of 0.4 mm was obtained. The unidirectional fiber reinforced tape of Example 1 had two colors, red and white.

<Example 2>
As Example 2 of the present invention, using the flame-retardant composite fiber 4a and the flammable composite fiber 4b, the two characteristics of flame-retardant and flammable are exhibited by the same method and conditions as in Example 1. A unidirectional fiber reinforced tape having was produced. At that time, the composite fiber 4a has a flat elliptical cross section like the composite fiber shown in FIG. 3B, the island component 13 is polypropylene, and the sea component 12 is a flame-retardant high-density polyethylene MB PEX FR- manufactured by Tokyo Ink Co., Ltd. It was formed of 0187AL, the cross-sectional area ratio of each component was island component: sea component = 65:35, and the fineness was 1850 dtex. Further, the composite fiber 4b has a flat elliptical cross section like the composite fiber 4a, the island component 13 is formed of polypropylene, the sea component 12 is formed of high-density polyethylene, and the cross-sectional area ratio of each component is the island component: sea component. = 65:35, and the fineness of 1850 dtex was used.

Then, eight flame-retardant composite fibers 4a and seven flammable composite fibers 4b are fed out from the bobbin stand, and the composite fibers 4a and the composite fibers 4b are alternately arranged to form a comb-shaped slit 6. Was passed through and converged. Next, the composite fiber bundles 4a and 4b were fused while being taken up at a linear speed of 2.8 m / min and pressurized under the condition of a linear pressure of 5 kg / m ² using a heating roller 7 heated to 130 ° C. Then, by cooling and solidifying, a unidirectional fiber reinforced tape having a thickness (average value of 5 points) of 0.4 mm was obtained.

<Example 3>
As Example 3 of the present invention, the unidirectional fiber reinforced composite material 10 of the second embodiment shown in FIG. 4 was produced. Specifically, a heating take-up roller having a protrusion having a substantially triangular cross section and a height of 0.1 mm was used on one surface of the fiber-reinforced composite material produced in Example 1, and the depth was 0.1 mm. A V-shaped groove continuous in the longitudinal direction was formed in the tape to form a unidirectional fiber reinforced tape of Example 3. Each groove was formed at the interface between the resin composition 2a derived from the sea component 12 of the composite fiber 4a and the resin composition 2b derived from the sea component 12 of the composite fiber 4b.

Next, 10 evaluation samples having a length of 50 mm were cut out from the unidirectional fiber reinforced tape of Example 3, chucked at positions 7 mm from both ends of each sample, and then 20 mm / min using a universal testing machine. A tear test was performed at speed. As a result, the unidirectional fiber reinforced tape of Example 3 was able to be divided into each characteristic (color) without cutting the continuous fiber 3 in 8 out of 10 evaluation samples.

<Example 4>
As Example 4 of the present invention, a unidirectional fiber reinforced tape having a thickness of 0.4 mm (average value of 5 points) was applied under the same method and conditions as in Example 1 described above except that a grooved thermal roller was used. Made. On both sides of the unidirectional fiber reinforced tape of Example 4, the interface portion between the resin composition 2a derived from the sea component 12 of the composite fiber 4a and the resin composition 2b derived from the sea component 12 of the composite fiber 4b is formed. , The depth was 0.05 mm, and a V-shaped groove continuous in the longitudinal direction was formed.

Next, 10 evaluation samples having a length of 50 mm were cut out from the unidirectional fiber reinforced tape of Example 4, and evaluated by the same method as in Example 3. As a result, in the unidirectional fiber reinforced tape of Example 4, it was possible to divide all 10 evaluation samples for each characteristic (color) without cutting the continuous fiber 3.

From the above results, according to the present invention, it is possible to impart two or more characteristics to the unidirectional fiber reinforcing material, and further, by forming notches or notches such as grooves at the interface of the resin composition, the characteristics It was confirmed that it is possible to divide the fiber reinforcing material for each.

1, 10 Fiber Reinforced Composite 2 Matrix 2a, 2b Resin Composition 3 Continuous Fiber 4a, 4b Composite Fiber 5a, 5b Robbing 6 Slit 7 Heating Roller 8 Winding Roller 11 Notch 12 Sea Component 13 Island Component

Claims (5)

A unidirectional fiber reinforced composite in which a plurality of continuous fibers are arranged in one direction in a matrix.
The matrix is composed of two or more kinds of resin compositions having different component compositions, and a region composed of one resin composition and a region composed of another resin composition in a cross section perpendicular to the longitudinal direction of the continuous fiber. Is a unidirectional fiber-reinforced composite material in which the resins are adjacent to each other and each resin composition is continuously present in the longitudinal direction of the continuous fibers. It has a sea-island cross-sectional structure in which a plurality of island components are scattered in the sea component, and is formed by using two or more kinds of composite fibers having at least the component composition of the sea component different from each other.
The unidirectional fiber reinforced composite material according to claim 1, wherein the matrix is composed of the sea component of each composite fiber, and the continuous fiber is composed of the island component of each composite fiber. The unidirectional fiber-reinforced composite material according to claim 2, wherein the sea component is a thermoplastic resin composition, and the island component is a thermoplastic resin composition having a melting point higher than that of the sea component. Claims 1 to 3 in which notches or notches are formed on at least one surface at the interface portion between the one resin composition and the other resin composition in a continuous or discontinuous manner in the longitudinal direction. The unidirectional fiber reinforced composite material according to any one of the above. The unidirectional fiber reinforced composite material according to any one of claims 1 to 4, which is a long sheet or tape.

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