JP2001096558A - Composite material and manufacturing method - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a composite material capable of enhancing a specific strength per weight and a specific strength per material cost at once and a method for manufacturing it. SOLUTION: A plastic wall b of the same type as or different type from a foamed plastic is formed between adjacent foamed plastic particles a, and a connecting strength between the adjacent particles a is enhanced by the wall b. In the composite material, the particles a are used as forms, and the wall b is build in a stereoscopic mesh-like state. Accordingly, a shape of the wall b becomes a honeycomb-like state (actually in a non-fixed form) as shown in Figure even by cutting at any section, thereby realizing a very rigid structure.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a composite material, and more particularly, to a lightweight and strong composite material, for example, a building material or a structural material, and further to a composite material which can be applied to applications requiring higher strength. About.

[0002]

2. Description of the Related Art Generally, plastic is generally "lighter and stronger" than structural materials such as metal and concrete.
It has the characteristic that. However, it is not always advantageous in terms of cost, and segregation was performed according to product characteristics. Further, for example, as a building material or a structural material, various foamed plastics such as styrene foam or foamed polyethylene are used. However, this kind of foamed plastic alone has insufficient mechanical strength and is used for an application in which a large load is applied. I couldn't do that.

[0003] Further, there are products such as sandwich plates made of foamed plastic as a core material capable of obtaining a light weight and a certain mechanical strength. Such a sandwich plate only needs to be light in weight to cope only with bending strength, but it was not possible with this type of sandwich plate to cope with various stresses such as tension, compression and torsion. In order to solve such disadvantages of the foamed plastic, for example, Japanese Patent Application Laid-Open No. 6-39936 discloses a foamed plastic which is lightweight and has excellent mechanical strength.

[0004]

However, the prior art disclosed in Japanese Patent Application Laid-Open No. 6-39936 can certainly reduce the weight and mechanical strength, but has the problem of increasing the manufacturing cost. Was. The present invention solves such problems of the prior art, and provides a composite material that can be widely spread by instantaneously increasing the specific strength per weight and the specific strength per material cost, and a method for manufacturing the same. With the goal.

[0005]

SUMMARY OF THE INVENTION In order to solve the above-mentioned problems, the present invention forms a wall of a plastic of the same type or different from that of a foamed plastic between adjacent foamed plastic particles, and the wall forms an adjacent foamed plastic by the wall. At the same time as increasing the bond strength between the particles, it itself builds a strong plastic wall.

According to the present invention, polystyrene beads containing a foaming agent are primarily foamed to form primary foamed particles, and the primary foamed particles are coated with a material having low thermal conductivity such as gypsum or a ceramic material. After the mixed liquid obtained by mixing the hardening agent and the glass fiber in the liquid unsaturated polyester at a fixed ratio into the pre-expanded foamed particles, the mixed foamed particles are added and stirred well. Filled into a mold, heated to secondary foam the polystyrene beads and simultaneously cure the unsaturated polyester, taken out of the mold and quenched at the same time, the reaction heat at the time of curing the unsaturated polyester is Prevents the secondary expanded polystyrene beads from melting.

[0007]

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a perspective view of a composite material according to an embodiment of the present invention. According to the present invention, a plastic wall of the same or different type from the foamed plastic is formed between adjacent foamed plastic particles, and the bonding strength between the adjacent foamed plastic particles is increased by the wall. It contributes to the strengthening of the composite structure and provides a structural material that is very strong in weight.

FIG. 1 is a schematic view showing the structure of a composite material according to the present invention. In FIG. 1, a symbol a indicates expanded plastic particles, and a symbol b indicates a plastic wall. In the present embodiment, the expanded plastic particles a are firmly joined by the plastic wall b. FIG. 2 is a partially enlarged view of FIG. 1 showing the structure of the composite material according to the present invention in more detail. As shown in FIG. 2, in the composite material according to the present invention, a coating material a 'is formed around the expanded plastic particles a, and a plastic wall b is formed around the coating material a'.

In the composite material of the present embodiment, the plastic wall b is constructed in a three-dimensional network using the foamed plastic particles a as a mold. Therefore, regardless of the cross section of the structure in the present embodiment, the shape of the plastic wall b becomes a honeycomb shape (actually, an irregular shape) as shown in FIG. 1, and a very strong structure can be realized. It becomes possible. Also, the foamed plastic particles a are guaranteed to have a strength against a compressive force if foamed at a low magnification to some extent.
In addition, since the foamed plastic particles a contain air in other than the structural surface, an excellent soundproofing and heat insulating effect can be expected with respect to the existing structural materials such as metal and concrete. Furthermore, the plastic wall b is FRP
(Fiber-reinforced plastics)
By doing so, it is possible to significantly increase the strength of the structure. Here, differences between the existing FRP structure and the FRP structure of the present embodiment will be described below.

FIG. 3 shows a general existing short fiber-dispersed FRP.
FIG. 3 is a structural diagram showing a structure. As shown in FIG. 3, in the existing FRP structure, the matrix 1 in which the fiber c is the base material is used.
Since the fibers are irregularly dispersed in three dimensions within 00, the ratio of the fiber c acting on the tensile stress in a specific direction is limited. On the other hand, in the present embodiment shown in FIG. 1, since the dispersion of the fiber c is limited to the two-dimensional direction as a surface, the fiber c effectively acts on the tensile / compression force in the surface direction of the wall b. Therefore, in the present embodiment, the strength can be more efficiently enhanced by the fiber. Further, in the case of FRP using a mat-shaped fiber fabric used in a bathtub or the like, it is very strong in pulling in the plane direction, but weak in bending in the direction perpendicular to the plane. Therefore, applications are limited according to such characteristics. On the other hand, in the case of the present embodiment shown in FIG. 1, since there is no directionality, it can be used as a structural material for any purpose.

Next, a method of manufacturing the composite material according to the embodiment shown in FIG. 1 will be described. In the following description, the case where the plastic wall b is made of FRP will be described as an example.
Also, foam plastic particles, matrix,
Although various materials can be considered as the fiber, in the following description, a case where expanded polystyrene particles-unsaturated polyester-glass fiber is used as the most likely combination in consideration of the production cost will be described as an example. Step 1 The polystyrene beads containing a foaming agent are primarily foamed. Step 2 A material having low thermal conductivity such as gypsum or a ceramic material is coated on the primary expanded particles. Step 3 A curing agent and a glass fiber are mixed into the liquid unsaturated polyester at a fixed ratio, and the mixture is stirred well. Further, coated foamed particles are added and stirred well. Step 4 The mixture is immediately charged into a mold coated with a release agent,
The polystyrene is secondarily foamed by heating, and at the same time, the unsaturated polyester is cured. Step 5: Take out from the mold and quench at the same time as to prevent the heat of reaction during curing of the polyester from dissolving the expanded particles. In the above manufacturing method, if the plastic wall b is not made of FRP, it is only necessary to add glass fiber to the step 3.

Next, items to be noted in the above manufacturing method will be described below. (1) In order to prevent the matrix from invading the expanded particles, it is necessary to control the thickness of the coating material to an appropriate thickness. (2) If the coating material is completely solidified, it inhibits secondary foaming and, at the same time, causes cracks at the time of secondary foaming to allow matrix intrusion.
Thereafter, it must be done as soon as possible. From the viewpoint of preventing cracking, an elastic rubber adhesive or the like may be added to gypsum or a ceramic coating material. (3) The secondary foaming and the curing of the matrix are controlled at an appropriate timing by the selection and amount of the curing agent, the heating temperature and time in Step 4, and the like. (4) The expanded particles can withstand heating for accelerating the curing of the matrix and reaction heat at the time of curing. Since the coating agent has a heat-resistant effect, the effect due to this is taken into consideration.

(5) If the selected coating agent has excellent elasticity, the mixture of polystyrene beads and the matrix may be foamed and cured immediately without dividing into two. (6) In consideration of compressive strength, it is desirable that the foamed plastic is not affected by heat. However, even if a part of the foamed particles is melted by the reaction heat at the time of curing the matrix, the foamed plastic functions as a mold. Is satisfied, the three-dimensional network FRP itself can maintain high mechanical strength. That is, the honeycomb structure can maintain high strength even when hollow. (7) As the material of the matrix, various materials can be considered in addition to the thermosetting plastic, and the approach of the manufacturing method changes depending on the selected material. That is, for example, if the strength is compromised, it is conceivable to use vinyl acetate which is compatible with polystyrene without a coating material. However, if the curing takes a long time, the rotation rate of the mold becomes worse, so this point must be considered. (8) When the viscosity and adhesiveness of the matrix are high, or when uniform mixing with the primary expanded particles is difficult due to a difference in specific gravity, take measures such as reducing the amount of the matrix and simultaneously spraying the matrix in a mist. I just need.

Next, the use of the composite material according to the present embodiment will be described. Building materials and furniture materials can be considered as applications where cost is a priority, i.e. where the proportion of fibers is low or contains no fibers.
In the case of building materials, there are uses such as floors and walls of condominiums and buildings, columns, floors, walls and roofs of detached houses. By using the composite material of this embodiment, it can be expected to contribute to weight reduction (= cost reduction, earthquake resistance), soundproofing and heat insulation, and shortening of construction period (= cost reduction) of a building. In addition, although the nonflammability has been increased by coating with gypsum or the like, it can be used as a fireproof material by further bonding a gypsum board or the like to the surface. Furthermore, by developing a construction method that does not use plywood forms, or by reducing the amount of wood used in detached houses, it is expected that forest resources will be saved (contribution to global environmental problems).

In the case of furniture materials, there are uses such as general furniture such as a chest, office furniture and the like. By using the composite material of this embodiment, it is possible to reduce the weight of furniture. Advantages of weight reduction include ease of transportation and prevention of the danger of falling during an earthquake. It can also contribute to environmental issues as well as building materials. Further, when the weight ratio strength is prioritized over the cost, the plastic wall b is made of FRP so that a strong composite material can be obtained, so that the invention can be applied to a mobile vehicle such as a passenger car or a railroad vehicle, an aircraft, or the like. . Lightening is required for mobile vehicles from the viewpoint of energy efficiency. The advantages are also great from the standpoint of sound insulation and heat insulation. When used in a car body, select and devise a material that takes heat resistance and water resistance into consideration.

[0016] Aircraft is the field that requires the most strength and light weight. If a composite material having this structure is constructed using a combination of high-strength engineering plastic and carbon fiber, superiority in weight ratio strength can be expected as compared to existing CFRP and aluminum honeycomb structures. In addition,
The embodiment described above is for describing the present invention,
The present invention is not necessarily limited to the above embodiment. That is, variations or modifications by those skilled in the art based on the technical concept of the present invention are included in the scope of the present invention.

[0017]

As described above, according to the present invention, it is possible to provide a composite material which is lightweight, has high strength, is excellent in soundproofing and heat insulating properties, and can be widely spread at a low production cost.

[Brief description of the drawings]

FIG. 1 is a sectional view showing the structure of a composite material according to the present invention.

FIG. 2 is an enlarged sectional view showing a more detailed structure of the composite material shown in FIG.

FIG. 3 is a structural view of a short fiber-dispersed FRP according to a conventional technique.

[Explanation of symbols]

 a foamed plastic particles a 'coating material b plastic wall

──────────────────────────────────────────────────の Continued on the front page (51) Int.Cl. ⁷ Identification symbol FI Theme coat ゛ (Reference) B29K 105: 04 B29L 31:10 B29L 31:10 B29C 67/22 F term (Reference) 2E162 CD05 FA02 FA14 FD02 4F072 AA02 AA06 AA07 AA08 AB09 AD05 AD38 AE01 AG04 AJ04 AK15 AL17 4F074 AA32 AA69 AC34 AE04 AG20 CA45 CA49 CC04Y CC05Z DA08 DA24 DA59 4F212 AA13 AA20 AD16 AG20 AH47 AH48 UA01 UB01 UB21 UF21 UN15

Claims (5)

[Claims] 1. A plastic wall of the same or a different type as the foamed plastic is formed between adjacent foamed plastic particles, and the wall increases the bonding strength between the adjacent foamed plastic particles, and at the same time, the plastic is constructed. A composite material characterized in that the walls themselves exhibit strength. 2. The composite of claim 1, wherein the plastic wall comprises fiber reinforced plastic. 3. The composite material according to claim 1, wherein a coating material is formed around the foamed plastic particles, and the plastic wall is formed around the coating material. . 4. The composite material according to claim 1, wherein a cross section of the plastic wall portion of the composite material has a honeycomb structure even when cut at any surface. 5. A polystyrene bead containing a foaming agent is primarily foamed to form primary foamed particles, and the primary foamed particles are coated with a material having low thermal conductivity such as gypsum or a ceramic material to form coated foamed particles. After thoroughly mixing the mixed solution obtained by mixing the curing agent and the glass fiber in the unsaturated polyester at a fixed ratio, the coated foamed particles are added and stirred well, and the mixed solution is quickly poured into a mold coated with a release agent. Filling,
The polystyrene beads are secondarily foamed by heating, and the unsaturated polyester is cured at the same time. By taking out from the mold and quenching at the same time, the heat of reaction at the time of curing the unsaturated polyester is the secondarily foamed polystyrene. A method for producing a composite material, comprising preventing beads from melting.