JP4311749B2 - Shape memory composite material and manufacturing method thereof - Google Patents

Description

  The present invention relates to a shape memory composite material and a method for producing the same, and more particularly, includes a layer of fiber reinforced plastic (FRP) or carbon fiber reinforced plastic (CFRP: hereinafter may be included in FRP) having shape memory properties. The present invention relates to a shape memory composite material having a multilayer structure and having inflatability.

In order to assemble materials by taking materials into outer space, etc., it is necessary to reduce the volume of the structure during transportation as much as possible. For example, in a satellite or space structure, a large device such as a panel for a solar cell is attached, but it is required to be downsized when transported from the ground. And what was folded at the time of conveyance is expand | deployed to the predetermined shape which is a use condition in outer space, such as a satellite orbit. Such a material characteristic that has compressibility and expandability that can be compactly compressed during transportation and can be expanded into a predetermined shape during use is referred to as so-called inflatable property.
Having such an inflatable property is of course important as a material property used for the ground structure. When an inflatable material is used, it can be stored compactly when loaded on a transport vehicle (volume). And can be developed into a predetermined shape when used at the site of assembly and construction.

Inflatable structures include those due to mechanical action such as folding of joint parts, and those due to material characteristic actions that return to their original shape upon heating.
Conventional inflatable properties are mostly due to a mechanical structure, and are in a form that folds at a joint portion. Therefore, it has been necessary to apply some force during use and to develop it into a predetermined shape. In addition, due to the structure, there has been a problem that troubles such as breakdowns and accidents may occur during deployment.

  On the other hand, several studies have been made on structures having inflatable properties due to material characteristic effects. In order to use a material having an inflatable property for a large structure, it is also necessary to be a hardened material having a certain degree of strength. Suitable examples of the hardened polymer material having strength include fiber reinforced plastic (FRP) and carbon fiber reinforced plastic (CFRP). In order to impart inflatability, a shape memory polymer is used inside. FRPs containing fiber materials are conceivable.

  The shape memory polymer is a resin that can be used in a normal polymer and can selectively use a molded shape and a deformed shape by a temperature operation by heat. The shape memory polymer molded body using this resin is deformed at a temperature higher than the glass transition point of the polymer and lower than the melting temperature or the decomposition temperature, and is cooled to the glass transition point (Tg) or lower while maintaining the shape. By fixing the deformed shape and heating it to a temperature above the glass transition point and below the melting temperature or decomposition temperature, the original molded shape is recovered. (For example, refer to Patent Document 1).

Usually, FRP is a fiber reinforced plastic comprising a continuous fiber material, and has a hardness similar to that of ceramic, a strength similar to that of metal, and a weight of about 1/8 that of a metal material. The elastic modulus is about 3 to 4 times that of iron. In such FRP and CFRP, it has been an important research subject from the past how much the fibers and the resin can be packed in the cross-sectional area.
In FRP, the fiber ratio determines the strength, so if the fiber ratio is increased, the strength is excellent. However, in order to form a molded body such as a plate shape, a resin is also required from the viewpoint of bonding the fibers to each other. . There are various types depending on the weaving and twisting of the fibers used for FRP. For example, cloth (cloth) with a width of about 10 m can be used, such as plates and pipes for large structures. Available.

  In general, a shape memory fiber reinforced plastic material is excellent in strength and rigidity like ordinary FRP. However, in a thin state having a certain amount of deformation related to shape memory performance, it has been difficult to obtain a certain degree of rigidity. That is, since the deformation amount of FRP is small, when a compact deformation is required, there is a limit to the plate thickness in order to obtain a plate shape, and it is necessary to reduce the thickness and maintain the deformation amount.

  On the other hand, when FRP is used effectively, the rigidity (bending rigidity) of a single thin plate-like FRP is low, so it is necessary to improve the rigidity of the plate-like body and obtain a plate-like body that is difficult to bend. is there. However, since the shape recovery / shape memory performance is better in the thin state, the shape recovery and shape memory (fixability) decrease when the thickness of the shape memory fiber reinforced plastic itself is increased. Therefore, there has been a demand for a structure having excellent rigidity while reducing the thickness of the shape memory fiber reinforced plastic itself.

On the other hand, a laminated structure using a fiber reinforced plastic has been known. For example, in the field of lightweight panels and the like, a rigid panel such as a thin FRP is laminated on both surfaces of a polyimide-based material plate to form a lightweight and strong laminate panel. However, sufficient research has not yet been conducted on laminates in which the laminate has shape memory properties.
JP-A-5-320366

In view of the above-mentioned problems, the present inventors have excellent strength that can provide sufficient rigidity in a structure having shape memory properties, and can sufficiently exhibit shape memory effects such as an original shape fixing / recovery function. In addition, in order to develop a structure that has both inflatable properties, we have intensively studied.
As a result, the present inventors have laminated a shape memory fiber reinforced plastic in combination with a layer composed of other components, and a multilayer structure that can sufficiently exhibit the shape memory function of the shape memory fiber reinforced plastic as a laminate. It was found that this problem can be solved by doing so. The present invention has been completed from such a viewpoint.

  The structure targeted by the present invention is a multilayer structure in which the laminate itself exhibits shape memory properties, and a fiber reinforced plastic having shape memory properties is used for the rigid portion of the laminate. In the present invention, the rigid body itself to be bonded has shape memory, so that the laminated body as a whole is also given shape memory. Therefore, a material that is softer than the fiber reinforced plastic is used as the other material to be laminated, and thereby the shape memory property of the laminated body is maintained. The combination of the fiber reinforced plastic which is a rigid body and the layer which is a soft body suppresses the thickness of the rigid body portion which is difficult to bend, while increasing the thickness at the soft body portion so that sufficient rigidity can be exhibited.

That is, the present invention provides a shape memory composite material consisting of a multilayer structure formed by laminating a layer made of at least a shape memory fiber-reinforced plastic layers and a polyurethane based shape memory foam, a layer made of the shape memory fiber reinforced plastic Is disposed outside the shape memory composite material, and the core layer sandwiched between the layers made of the shape memory fiber reinforced plastic has a sandwich structure in which the layer is made of the polyurethane-based shape memory foam. A memory composite material is provided.

The present invention also includes a step of forming a layer made of shape memory fiber reinforced plastic, a step of forming a layer made of polyurethane shape memory foam, and a layer made of shape memory fiber reinforced plastic. Sandwiching a layer made of foam, and laminating the layer made of shape memory fiber reinforced plastic to form a sandwich structure arranged outside, and forming a composite material made of a multilayer structure, A method for producing a shape memory composite material is provided.
In the step of forming a composite material having a multilayer structure by laminating layers, the layers can be bonded using an adhesive and cured by heating. Although heating is arbitrarily performed according to the kind of adhesive agent, it can be performed for about 10 minutes-about 5 hours, for example at normal temperature-about 200 degreeC. As the adhesive, for example, a shape memory polymer component used in a shape memory fiber reinforced plastic, another shape memory polymer, and a shape memory polymer component of a shape memory foam can be used.

  In the production method of the present invention, a prepreg can be used as the shape memory fiber reinforced plastic. For example, a laminate in which a plurality of shape memory fiber reinforced plastics are laminated as a prepreg can be used.

  Moreover, in the manufacturing method of this invention, in the process of shape | molding the said composite material, a shape memory resin component can be apply | coated to the bonding part of each layer in lamination | stacking. The shape memory resin component is preferably the same resin composition as any one of the shape memory fiber reinforced plastic and the polyurethane resin. This makes it possible to easily improve the adhesion between the layers to a sufficient level.

Furthermore, the present invention provides a step of forming a layer made of shape memory fiber reinforced plastic, a step of placing the obtained layer made of shape memory fiber reinforced plastic in a mold for shape memory foam molding, Forming a layer made of a shape memory foam, a core layer having the shape memory fiber reinforced plastic layer disposed outside and sandwiched between the shape memory fiber reinforced plastic layers, the shape memory foam And a step of simultaneously molding a composite material having a multi-layer structure laminated in a sandwich structure, which is a layer made of the above-mentioned layers, and a method for producing a shape memory composite material.

In the present invention, as a sandwich structure, the shape memory fiber-reinforced plastic is rigid is to form a layer placed outside, a layer sandwiched layer made of the shape memory fiber-reinforced plastic (core layer) foam But (foam), the shell effect, improving the rigidity and strength of the composite material. On the other hand, in the sandwich structure, the shape fixing / recovery function, etc., exhibits a better shape memory performance than the case where the core layer has the same thickness because the core layer is softer than the shape memory fiber reinforced plastic. To do.

  Further, in the above sandwich structure, if a shape memory fiber reinforced plastic is disposed on the outer side and a material having a large degree of deformation freedom is disposed on the core material, a material having high strength, high rigidity and high degree of deformation freedom is obtained. In particular, when the core material is a foam, the core portion can be compressed during deformation, so that the plate thickness is reduced and the degree of freedom of deformation is dramatically improved. In particular, when a shape memory foam is used for the core material, the core material itself has a shape memory characteristic, which is preferable.

  Since the shape memory foam and the shape memory polymer used in the present invention are polyurethane-based resins, when space environment is considered, they are easily deteriorated by ultraviolet rays, electron beams or the like. In the present invention, by combining these polyurethane-based resins and shape memory fiber reinforced plastic, the material deterioration of the core layer member can be suppressed by the shielding effect by covering the outside with (shape memory) CFRP or the like.

  Since the shape memory composite material of the present invention has a layer of shape memory fiber reinforced plastic and is laminated with a layer of polyurethane resin or the like, it has an inflatable property and takes the second shape by applying heat. be able to. By properly using such two or more shapes and physical properties in the shapes, the shape memory composite material of the present invention can be applied to various applications. In particular, when the glass transition point of the polymer is set to around room temperature, it can be easily deformed, fixed, developed and expanded as needed using a simple heating means.

  According to the shape memory composite material of the present invention, it is possible to provide a laminate having excellent rigidity while sufficiently maintaining bendability, shape fixing, and shape recoverability while reducing the thickness of the shape memory fiber reinforced plastic itself. . That is, the shape memory composite material of the present invention can impart sufficient rigidity and strength as a structure having shape memory properties. Moreover, even if it is a laminated body, shape memory actions, such as an original shape fixing / recovery function, can fully be exhibited.

Hereinafter, the manufacturing method of a shape memory composite material is demonstrated with each component used for the shape memory composite material of this invention.
The present invention provides a shape memory composite material having a multilayer structure in which two or more layers are laminated. At least one layer in the multilayer structure is a layer made of shape memory fiber reinforced plastic. Examples of the other layer include a layer made of a polyurethane-based resin. As the polyurethane-based resin, a shape memory polymer or a shape memory foam is preferable.

Since the FRP used in the present invention has a shape fixing / recovering function, in order to make use of this shape fixing / recovering function, the layer made of shape memory fiber reinforced plastic needs to have a certain thickness or less. . On the other hand, since the thin layer is inferior in rigidity inherent to FRP, the material as a whole needs to have a certain thickness or more. In order to provide this thickness, the present invention has a multilayer structure including layers composed of other components. For the layer composed of other components, it is preferable to use a shape memory polymer from the viewpoint of shape recovery, and if a shape memory foam is used, the shape recovery function is further improved.
Further, in the multilayer structure of the present invention, it is preferable to provide FRP in the outermost layer and provide at least one soft body layer on the inner side, and an embodiment using a shape memory foam in the core layer can be mentioned. If the thickness of the core layer is large, the rigidity is improved by the shell effect and the deformation strain applied to the laminated body can be absorbed. Therefore, the core layer can be deformed while having rigidity, and the deformation ability is enhanced. In particular, when a shape memory foam is used for the core layer, the core layer itself is also compressed and deformed at the time of deformation, so that the thickness of the plate can be greatly reduced. It can have shape deformation ability.

  Specifically, the shape memory fiber reinforced plastic used in the present invention includes, for example, a bifunctional and trifunctional liquid isocyanate, a bifunctional polyol, and a bifunctional chain extender containing an active hydrogen group. What is obtained by impregnating a fiber material into a resin composition (composition 1) prepared in a molar ratio of isocyanate: polyol: chain extender = 5.0 to 1.0: 1.0: 4.0 to 0 and then curing the resin composition. It is done. In addition, as another resin composition (Composition 2), a difunctional or trifunctional isocyanate and a polyol having an average molecular weight of 100 to 550 are represented by a molar ratio of functional groups: isocyanate: polyol = 0.9 to 1.1: 1.0. Including.

  As a characteristic of the resin composition, in order to sufficiently permeate the fiber material, initial impregnation is required and at the same time, a certain pot life is required. The resin composition preferably has a viscosity of 1000 cps or less by measuring the viscoelasticity in consideration of the impregnation property into the reinforcing fiber. Moreover, in order to secure a sufficient impregnation time of the resin composition into the fiber material and obtain a dense FRP molded product, the pot life is preferably 30 minutes or longer, preferably 60 minutes or longer. The pot life here is the time until the viscosity rise time of the resin composition reaches, for example, 1000 cps. On the other hand, in order to develop the inflatable function of the molded FRP, it is desirable that the Tg of the resin composition is about 40 to 150 ° C., preferably about 70 to 120 ° C., from the viewpoint of maintaining shape memory properties.

Although the raw material which can be used for the said resin composition is illustrated next, it is not limited to these.
Examples of difunctional and trifunctional isocyanates can be represented by the general formula OCN-R-NCO, where R has one or two benzene rings and none at all. Specific examples thereof include 2.4-triene diisocyanate, 4.4'-diphenylmethane diisocyanate, carbodiimide-modified 4.4'-diphenylmethane diisocyanate, hexamethylene diisocyanate, and the like.

Examples of bifunctional polyols can be represented by the general formula HO-R'-OH, where R 'has one or two benzene rings, and those having the above two functions. Examples thereof include products obtained by reacting a polyol with a bifunctional carboxylic acid or a cyclic ether, such as polypropylene glycol, 1.4-butane glycol adipate, polytetramethylene glycol, polyethylene glycol, bisphenol-A + propylene oxide. Etc.
In the present invention, among the above polyols, an ether type which is not concerned with hydrolysis and is preferably an aromatic type or an aliphatic side chain type which can increase Tg in terms of molecular design. In particular, in the above compound, polypropylene glycol is preferable, and the content of the monomer in the polyol component is usually 50% by weight or more, preferably 70% by weight or more, and more preferably 90% by weight or more.

  As an example of a bifunctional chain extender containing an active hydrogen group, it can be represented by the general formula HO-R "-OH, where R" has a (CH2) n group and one or two benzene rings. Any of these groups can be used. Specific examples include ethylene glycol, 1.4-butane glycol, bis (2-hydroxyethyl) hydroquinone, bisphenol-A + ethylene oxide, bisphenol-A + propylene oxide, and the like. Such a chain extender has a role of a Tg adjusting agent in the resin composition, and is particularly used to maintain a high Tg.

The resin composition of composition 2 does not contain the chain extender. Chain extenders have the role of Tg modifiers in polymer compositions and are used to maintain high Tg, while tending to shorten pot life, Without using such a chain extender, the resin composition of Composition 2 has a high Tg by using a low molecular weight polyol and controlling the content ratio of isocyanate and polyol.
When using a resin composition containing a difunctional or trifunctional isocyanate and a polyol in a functional group molar ratio of isocyanate: polyol = 0.9 to 1.1: 1.0, the average molecular weight is usually the polyol. Use 100-550. In the case of this resin composition, when the molecular weight of the polyol exceeds 550, there is an advantage that the usable time of the obtained shape memory polymer becomes long, but since Tg is lowered, shape memory such as shape fixation and shape recovery in the space environment is reduced. It becomes impossible to maintain the Tg of the polymer composition necessary for developing the property at 40 ° C. or higher. On the other hand, when the average molecular weight is less than 100, the pot life required for FRP molding cannot be secured. The average molecular weight of the polyol is preferably 150 to 250.
In this resin composition (composition 2), the mixing ratio of isocyanate and polyol is the molar ratio of functional groups, and is: isocyanate: polyol = 0.9 to 1.1: 1.0 (ie, NCO / OH = O.9 to 1.1). is there. By setting it as such a mixing ratio, the polymer composition which has high Tg which can express shape memory property, such as shape fixation and shape recovery, can be obtained, ensuring required pot life.

  Additives can be added to any of the above resin compositions within a curable range. As the additive, one or more commonly used additives such as various fillers, organic components, and diluents can be added.

The fiber material is not limited to fibers made of organic materials, and inorganic fibers such as glass fibers and carbon fibers can be used. Specifically, for example, an aramid fiber is suitable. Although the woven structure is not limited, for example, a plain weave material made of warp and weft is used, and the thickness is, for example, in the range of 0.1 to 1.0 mm.
Further, the fiber reinforced plastic used in the present invention may contain reinforcing fibers, pigments and the like in addition to the resin composition and the fiber material, and the amount ratio thereof is not particularly limited.

  Regarding the fiber reinforced plastic used in the present invention, the composition ratio between the resin composition and the fiber material is not particularly limited, but the volume content of the fiber material is usually 5 to 75% by volume, preferably 10 to 60% by volume. More preferably, it is contained in a proportion of 20 to 55% by volume. Here, the theoretical volume of the fiber material in the FRP can be calculated as a value obtained by dividing the value of the fiber material weight per unit area into consideration by the density of the fiber material. If the fiber material is less than 5% by volume, the strength due to the fiber material is not sufficiently exhibited, which is not preferable. If the fiber material exceeds 75% by volume, it is difficult to form and the resin impregnation is insufficient and it is difficult to obtain a good product. . On the other hand, when the fiber material exceeds 60% by volume, the inflatability by the polymer composition is not sufficiently exhibited. Within the range of the volume content, when the composition ratio of the fiber material is increased, the obtained molded body has high strength, whereas when a large amount of resin is blended, the shape fixing property is improved.

Specifically, the shape memory foam (polyurethane foam) used in the present invention is a polyisocyanate, a polyol, a chain in the presence of a foam stabilizer and a foam stabilizer including a siloxane-oxyalkylene block copolymer. Examples thereof include a shape memory polyurethane foam obtained by reacting a foam material containing an extender and / or a crosslinking agent. The blending ratio of the chain extender is 1 to 15 parts by weight with respect to 100 parts by weight of the polyol, and the blending ratio of the crosslinking agent is 5 to 45 parts by weight with respect to 100 parts by weight of the polyol.
The glass transition temperature of such a shape memory polyurethane foam is 40 to 80 ° C., which is an important physical property for ensuring ease of handling at room temperature and for exhibiting shape memory properties in an easy-to-use temperature range. If the glass transition temperature is less than 40 ° C., shape memory property at room temperature does not appear, and if it exceeds 80 ° C., the amount of heat imparted until the rubber state is increased is not preferable. On the other hand, if the glass transition temperature is in the above range, both stability when the shape is fixed and shape reproducibility when the temperature changes beyond the glass transition temperature are preferable.

  Such a shape memory polyurethane foam is deformed at a temperature not lower than the glass transition temperature and lower than the melting temperature or the decomposition temperature, and the deformed shape is fixed by cooling to a temperature lower than the glass transition temperature while maintaining the shape. By heating to a temperature above the glass transition temperature and below the melting temperature or decomposition temperature, the original molded shape is recovered, and the shape can be properly used depending on the temperature operation.

  The shape memory polymer used in the present invention is composed of a shape memory polymer material such as polyurethane, and is distinguished from the shape memory foam as the foam material and the shape memory fiber reinforced plastic including the fiber material. The As a composition, the sheet-like thing etc. which consist of resin compositions (the said composition 1, 2 etc.) used for manufacture of the said shape memory fiber reinforced plastics are mentioned.

In FIG. 1 (c) and (d), it shows a cross-sectional view schematically showing a lamination of a multilayer structure shape memory composites of the present invention. 1A and 1B are reference diagrams. As the constituent materials A, B, and C in the drawing, a shape memory foam reinforced material, a shape memory polymer material, a rubber material, an elastomer, and the like can be appropriately selected in addition to the shape memory fiber reinforced plastic.

In the case of the two-layer structure shown in FIG. 1A, when the shape memory FRP, which is a rigid material, is used as the constituent material A, a soft body such as a rubber sheet can be used as the constituent material B. In the case of CFRP for A and a rubber sheet for B, the shape of the composite material can be fixed and recovered by the rigidity of FRP of A. Since the rubber sheet can be deformed sufficiently, when shape memory FRP is bonded to the rubber sheet, bending and deforming the composite material of the laminate will increase the rigidity of the FRP rather than the restoring force of the rubber. In this case, the shape as it is can be stored (fixed). In the case of this two-layer structure, the constituent material A can be FRP, and the shape B can be a shape memory foam.
Specifically, the shape memory fiber reinforced plastic formed by impregnating the fiber composition into the resin composition of the above composition 2 can be used as the FRP used for the constituent material A. More specifically, the thickness of the CFRP of the A layer can be set in the range of 0.1 to 1.0 mm, for example, 0.25 mm. More specifically, the thickness of the foam used for the constituent material B can be set in the range of 1.0 to 30.0 mm, for example, 5.0 mm.

  In the case of the three-layer structure shown in FIG. 1B, for example, CFRP can be used as the constituent material A, a shape memory foam can be used as B, and a rubber sheet having light resistance can be used as C. In addition, as the constituent material C, a shape memory polymer (composition 3) obtained by adding 5 to 30% by weight of talc to the resin composition of the above composition 2 and molding it into a sheet shape can be used. More specifically, the thickness of the polymer material used for the constituent material C can be set in the range of 0.1 to 1.0 mm, for example, 0.25 mm. The thickness of CFRP of the A layer and the thickness of the foam used for the constituent material B are the same as in the case of FIG. In the case of a laminated body having this multilayer structure, shape memory / recovery is possible.

The case of a three-layer structure (sandwich structure) shown in FIG. 1 (c), the material A is a layer of the outer surface is a shape memory FRP, the material B is the core layer is Ru shape memory foam der. In this sandwich structure, it is preferable to use a polyurethane-based resin for the core layer, and the adhesiveness with the shape memory fiber reinforced plastic provided on both outer surfaces is good. More specifically, when the constituent material A is CFRP and the shape memory foam is B, CFRP is preferably used as the constituent material A, and the shape memory polymer of the above composition 3 is preferably used as the B material.
The thickness of the CFRP of the layer A, and the thickness of the foam used for the constituent material B, and the same as in FIG. 1 (b). Construction material B material is used to vary the soft body at a constant temperature above as the shape memory foam.
In the case of a four-layer structure as shown in FIG. 1D, in addition to the sandwich structure, a soft layer made of another polyurethane resin different from the constituent material B is further provided in the core layer.

Further, in the case of a laminate having the structure shown in FIGS. 1B, 1C and 1D, the constituent material B which is the core layer is made into a foamed body, so that the laminated body has rigidity due to the shell effect. The foam layer can be crushed to exhibit a volume reduction effect. If the constituent material A is a shape memory fiber reinforced plastic, it has a shape fixing / recovery function similar to that of a thin FRP having the same thickness after volume reduction. For example, when the thickness after crushing a laminate having a thickness of about 10 mm is about 1 mm, the deformation and shape memory performance are the same as the shape memory FRP having a thickness of 1 mm. And after restoring and expanding the foam, a rigid thickness of 10 mm can be obtained.
As the foam used for the core layer, a polyurethane foam which is a shape memory foam can be used. Since the shape memory foam can be expanded to an expansion ratio of about 5 to 50 times, it can be expected to have a volume-reducing effect that the volume can be reduced to 1/50, and can be easily bonded to a shape memory fiber reinforced plastic.

Even if the composite material of the present invention is a laminate structure as shown in FIG. 1 (c) and (d), by the other layers except the layer consisting of a shape memory fiber-reinforced plastic is a polyurethane-based resin, laminating extremely easy There is little peeling. And in the process of shape | molding a composite material, a shape memory resin component can be apply | coated to the bonding part of each layer in lamination | stacking. This shape memory resin component is preferably the same resin composition as any one of shape memory fiber reinforced plastic and polyurethane resin.

The shape memory composite material of the present invention shown in FIG. 1 can be arbitrarily changed in thickness according to its use and purpose, and the thickness is not limited at all.
For example, in the sandwich structure shown in FIG. 1C, the constituent material B of the core layer is a shape memory foam having a thickness of 10 mm, the constituent material A is CFRP having a thickness of 0.25 mm, and the shape memory composite material The case where it is a laminated body whose whole thickness is 10.5 mm is mentioned. In this laminate, the constituent material B of the core layer is a foam, and the layer is crushed to reduce the volume, thereby forming a plate-like body having an overall thickness of about 0.5 to 1.5 mm. Can do. The plate-like body reduced in volume as described above can be bent sufficiently and has a shape memory function.

When the shape memory fiber reinforced plastic is CFRP and the amount of fibers in the CFRP is about 40%, the layer thickness exhibits a shape recovery function in the range of, for example, 0.1 mm to 2.0 mm.
The shape memory fiber reinforced plastic used in the present invention is an important characteristic that has inflatable properties in addition to the basic physical properties as FRP, but in addition to resin properties and fiber material properties, the resin content, The orientation of the fiber or the laminated structure of the FRP itself also affects. When a general carbon fiber cloth (CF cloth) and a two-part curing type memory polymer are used, and FRP is molded by hot press, the FRP can be changed even if the number of laminated CF cloth is changed from 1 to 5. When the thickness is within the above range, it has inflatable properties.
Since the laminate of the present invention has a shape memory function, the thickness of the layer made of the shape memory fiber reinforced plastic is within a range in which the shape memory fiber reinforced plastic exhibits shape memory performance.

An example of the method for producing the shape memory composite material of the present invention will be described. In the production method of the present invention, first, a layer made of shape memory fiber reinforced plastic is formed. Separately, a layer made of polyurethane resin is formed. These layers are laminated to form a composite material having a multilayer structure. At this time, it is possible to perform pressure bonding without using an adhesive, but it is possible to securely bond both layers by applying a part of the resin composition to one layer. The bonding can be performed by heating.
Specifically, in the step of forming a composite material by laminating layers, the layers can be bonded together using an adhesive and heated to be cured. In the case of heating, it can be carried out usually at about 80 to 200 ° C., for example, 150 ° C., usually for about 10 minutes to 5 hours, for example about 1 hour. As the adhesive, a resin composition (composition 1, 2, etc.) used for shape memory fiber reinforced plastics can be used.

A prepreg can be used as the shape memory fiber reinforced plastic. A semi-cured material can be used as the shape memory polymer.
Further, in the present invention, a step of forming a layer made of shape memory fiber reinforced plastic, a step of placing the obtained shape memory fiber reinforced plastic in a mold for shape memory foam molding, and a shape in the mold Forming a layer made of a memory foam and simultaneously molding a composite material made of a multilayer structure.

  Although the embodiments of the present invention have been described above, the present invention is not limited to the above-described embodiments, and various modifications and changes can be made without departing from the scope of the present invention. is there.

(C) and (d), an example of the structure of the shape memory composites of the present invention Ri FIG der schematically showing, (a) and (b), Ru reference diagram der.

Claims (6)

A shape memory composite material consisting of a multilayer structure formed by laminating a layer made of at least a shape memory fiber-reinforced plastic layers and a polyurethane based shape memory foam, a layer made of the shape memory fiber-reinforced plastic, said shape memory composite A shape memory composite material characterized by having a sandwich structure in which a core layer disposed outside the material and sandwiched between layers made of the shape memory fiber reinforced plastic is a layer made of the polyurethane-based shape memory foam . A step of forming a layer made of shape memory fiber reinforced plastic, a step of forming a layer made of polyurethane shape memory foam, a layer made of shape memory fiber reinforced plastic and a layer made of polyurethane shape memory foam A shape memory composite material comprising a step of sandwiching and stacking the shape memory fiber reinforced plastic layers so as to form a sandwich structure disposed outside, and forming a composite material having a multilayer structure. Production method. The method for producing a shape memory composite material according to claim 2 , wherein a prepreg is used as the shape memory fiber reinforced plastic. The method for producing a shape memory composite material according to claim 2 or 3 , wherein, in the step of molding the composite material, a shape memory resin component is applied to a bonded portion of each layer in the lamination. The method of manufacturing a shape memory composite material according to claim 4 , wherein the shape memory resin component is the same resin composition as any one of the shape memory fiber reinforced plastic and the polyurethane resin. A step of forming a layer made of shape memory fiber reinforced plastic, a step of placing the obtained layer made of shape memory fiber reinforced plastic in a mold for shape memory foam molding, and a shape memory foam in the mold A sandwich made of the shape memory fiber reinforced plastic, the core layer sandwiched between the shape memory fiber reinforced plastic layers is a layer made of the shape memory foam Forming a composite material having a multilayer structure laminated on the structure at the same time, and manufacturing the shape memory composite material.

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