JP2001009857A - Manufacture of plastic foam composite - Google Patents

Abstract

PROBLEM TO BE SOLVED: To solve those unconveniences that even though s foam exhibits excellent heat insulating properties, when it is brought into contact with water or it is placed at a place with high humidity, it absorbs moisture to remarkably decrease the heat insulating properties and to exhibit no strength and to shrink with time. SOLUTION: When a plastic skin is prepd. on a foam with uniform and fine air bubbles and low density, no decrease in heat insulating properties caused by moisture absorption occurs and strength is improved and no shrinking properties is generated with time. A foamed composite like this is obtd. by a method wherein a powder plastic and a compsn. being a polyolefin crosslinked foamable granulated body wherein at least 0.2 PHR org. peroxide is incorporated and at least 5 PHR decomposable exothermic foaming agent are compounded are movably placed in a mold and are heated while they are rotated to prepare a skin with a uniform thickness and a layer of granules is uniformly distributed and stuck thereon and foaming is all at once performed by elevating temp. of the mold and the temp. of the skin material to the decomposition temp. of the foaming agent and then, the compd. is quenched.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001] The present invention relates to a method of placing plastic powder or fine granules and particles of the powder or crosslinked expandable granules larger than the fine granules in a mold so as not to apply a centrifugal force to the material in the mold. Heat from the outside while rotating, melt the powdered plastic on the inner surface of the mold to form a skin, and attach expandable granules on it, and set the mold temperature and the skin temperature to the decomposition temperature of the foaming agent. This is a method for producing a foamed composite in which a foaming agent is decomposed, a mold is filled with a crosslinked foam to form a core, and then the core is cooled, and the entire surface of the foam is covered with a plastic skin.

[Field of the Invention] Heat insulating materials, building materials, cushion materials, and floating materials.

[Prior Art] Plastic foams are:
It is composed of extremely small bubbles and a bubble film surrounding the bubbles, and has a high volume fraction of gas and low convection. Therefore, it is inexpensive, has excellent heat insulating properties, has good cushioning and buoyancy, and is widely used in various fields. On the other hand, foams have such characteristics, but have low strength and are difficult to use alone, and also have the drawback that they absorb moisture, reduce heat insulation, and shrink over time. Improvement of these drawbacks is strongly desired. ing.

In order to remedy these drawbacks, a plastic foam is provided with a thick skin on the surface of the plastic foam. One of the techniques is a method in which a skin is formed by rotational molding, and polyurethane is injected and foamed therein. This improves the strength and moisture absorption of the plastic foam, but this method requires two molds in two steps, is costly, has insufficient adhesion between the skin and the core, and has a high impact resistance. ， Bending strength is not enough. The other is to make the skin by blow molding, put the pre-foam into it, heat it and integrate it, and this method is expensive in three steps, and the heating and integration of the pre-foam is Since it cannot be performed at a high temperature, the adhesion between the skin and the core is not sufficient, and the impact resistance and bending strength are not good.

[0005] There is a technique in which a plastic powder and an expandable granular material are simultaneously placed in a mold, and the resulting mixture is rotationally molded to produce a foam composite comprising a skin and a foam. According to this method, the molded body can be manufactured in one step and the cost is low. Since the skin and the core are simultaneously formed in the mold, the adhesion between the two is good, and the impact resistance and the bending strength are excellent. This technique was discovered about 30 years ago by one of the inventors, and it was found that usp 3.814.778, usp
3.914.361. In this technology, two kinds of materials are put in a mold at the same time, the skin and the core are molded at the same time, and the core is crosslinked and foamed in the mold, and it is difficult to mold because it is molded according to the shape of the mold, Even after 30 years, it has not yet been produced in a factory. With this technology, it is difficult to completely separate the skin and the core, the thickness of the skin tends to be uneven, pinholes in the skin, voids and distortions in the core, and it is difficult to form a molded product according to the shape of the mold .

[Problems to be Solved by the Invention] The present invention is lightweight, strong, and excellent in heat insulation and cushioning properties. It is an object of the present invention to establish a production technique capable of easily and surely obtaining a foam composite comprising a skin and a foam which does not deform.

[Embodiment of the Invention] The inventor of the present invention has conducted research on this technology for many years and has arrived at the present invention. According to the present invention, powdered plastic and larger crosslinked foamable granules are placed in a mold, and the material is heated from the outside while being slowly rotated so as not to give a centrifugal force to the material. As a result, first, powdered plastic having a small particle size adheres to the inner surface of the mold to form a skin having a uniform thickness, and then expandable granules are uniformly distributed and adhered on the skin, and further heated to mold. When the temperature of the skin and then the temperature of the skin reach the decomposition temperature of the foaming agent, the crosslinked foamable foam expands to become a foaming material of polyhedral cells, and the mold is filled to form a foamed composite. That is, the present invention utilizes the fact that the cells of the crosslinked polyolefin foam are stable at the decomposition temperature of the blowing agent, and that the particles are separated into the epidermis and the foaming phase by rotating small particles and large particles. This is a technique for producing a foamed composite with a skin in one step.

According to the present invention, the powdered plastic and the foamable granules having a larger size are placed in a thick mold, and the powdered plastic is uniformly heated by slowly rotating it while maintaining a uniform temperature. A skin having a large thickness is formed, and large crosslinked expandable granules having a large shape are deposited on the skin in a single layer and uniformly distributed. Next, when the temperature of the skin inside the mold rises and reaches the decomposition temperature of the foaming agent, since a large amount of the decomposing and exothermic foaming agent is added to the foamable granules, each granule comes into contact with the mold. Since the foamable particles are uniformly distributed in the mold, the foam expands simultaneously while maintaining a similar shape from the inner wall of the mold toward the center of the mold. Although heat is generated by the decomposition of the foaming agent, since the foaming agent is uniformly dispersed in a large amount of polyolefin, the temperature of the foam remains at a temperature near the decomposition temperature of the foaming agent, and the moving distance of the foam is Since the core is relatively short from the inner surface of the mold to the center of the mold, the core is free from voids and distortion, and the foam is a uniform and fine cell foam. Therefore,
A foamed composite as shown in FIG. 1 having excellent heat insulation properties, it is lightweight and strong, and becomes a molded body that does not shrink over time in the shape of a mold.

The skin material of the present invention is a powder of a thermoplastic resin such as polyolefin, nylon, ABS or the like, or a semi-cured powder of a thermosetting resin. Preferred is polyolefin because of low moisture absorption, and more preferred is high density polyethylene. High density polyethylene has particularly good adhesion to the foam of the present application. The skin of the present invention has a thickness of 0.25 mm or more, and a skin not reaching 0.25 mm has no strength, and absorbs the heat insulating layer through moisture to lower the heat insulating property. The powder for the epidermis is preferably spherical,
Crushed bearded materials have poor formability. The thickness of the skin is preferably 0.5 mm or more, more preferably 1.0 mm or more.
mm or more. In the case of a skin having a thickness of more than 7 mm, heat escapes through the skin layer, so that the heat insulation of the molded body is deteriorated and the molded body is easily broken by impact.

The skin of the present invention needs to have a ratio of the minimum thickness to the standard thickness of 1/2 or more. If a portion having a minimum thickness smaller than that is formed, the heat insulating property and the mechanical properties are reduced. In the present invention, in order to improve the heat insulation,
The foam may be slightly foamed as shown in the figure, but this is limited to foam having a density of 0.25 g / cc or more of spherical cells. The foam of spherical cells has strength, and has good heat insulation and moisture absorption resistance. In the present invention, two or more layers of skin can be produced using two or more kinds of powders and fine granules having different sizes. At this time, it is necessary that the average particle size of one skin material is twice or more the average particle size of the other. Therefore, in order to form three skin layers, three kinds of skin materials having an average particle diameter of 1, 2, and 4 times are used. Using this technology, one skin is made into a spherical foam skin, and a thin non-foamed skin is placed on it to create a complex as shown in Fig. 3 that has thermal insulation and a smooth surface. Can be done.

The skin of the present invention may also contain a crosslinking agent. Thereby, the unevenness of the epidermis can be reduced. A soft skin can be formed by using a crosslinked skin of an ethylene vinyl acetate copolymer, an ethylene ethyl acrylate copolymer or a linear low-density polyethylene having a density of 0.910 g / cc or less, and is used as a cushion material. The present inventors studied a method for producing a composite having a uniform thickness of the skin, and found that the angular frequency of the powdered plastic used for the skin at 190 ° C. was 1 (ra).
It has been found that this object can be achieved by using a material having a storage modulus (d / s) of 1 × 10 ³ (Pa) or more.
Here, the storage elastic modulus means that when a periodic (sinusoidal) stress is applied to a sample, the corresponding strain also changes periodically (sinusoidally), but the phase shifts. When the stress is divided by the strain, the elastic modulus is obtained. When this is expressed in vector or complex, G = G ′ + iG ″. The real part of the elastic modulus is called the storage elastic modulus, and the imaginary part is called the loss elastic modulus. The method of measuring the storage modulus is carried out, for example, with a cone plate rheometer, since it relates to the storage and loss of energy (dissipated as heat), respectively. Opposite (cone apex toward disk center)
Between which a viscoelastic liquid or melt is filled. By vibrating a disk periodically, the viscoelastic constant (for example,
G ′, G ″). The powdered plastic used in the present invention is a thermoplastic resin powder having a storage modulus of 1 × 10 ³ (Pa) or more, and a preferable storage modulus is 5 × 10 ³ (Pa).
³ (Pa) or more, more preferably 1 × 10 ⁴ (Pa)
That is all.

In some cases, a resin having a low storage modulus compatible with a resin having a high storage modulus, such as a medium-density polyethylene, is mixed and used, thereby improving the impact resistance. In some cases, low-density polyethylene is mixed with high-density polyethylene to improve the elastic modulus. Another reason to select a storage modulus in this range is to increase the ratio of the minimum thickness to the average thickness and make the skin thickness uniform. The skin material of the present invention may contain inorganic fillers, fibers and the like, which may make the skin thickness uniform and flame retardant. Carbon black and stainless steel fibers may be used to reduce static electricity. It can be prevented. Also, fungicides,
Antibacterial agents, pigments, etc. may be used. The crosslinked expandable granular material of the present invention is obtained by crosslinking polyolefin mixed with a crosslinking agent and a blowing agent or polyolefin mixed with a blowing agent with ionizing radiation. The crosslinked polyolefin foam has good heat resistance and the temperature at which the blowing agent decomposes is 200 ° C.
However, the elastic modulus does not decrease, the cells are stable, the production of a foamed composite having a skin is enabled, and a molded article in which the skin and the foam are completely bonded can be obtained.

The crosslinking agent of the present invention is an organic peroxide such as dicumyl peroxide, 2.5 dimethyl 2.5 di-tert-butyl peroxyhexane. The decomposition temperature of the cross-linking agent is about 160 ° C and the amount added is 0.2 PHR or more,
HR or less, preferably 0.5 PHR or more, 1.0 PH
R or less. Thus, a high-magnification foam of polyhedral cells can be produced. A cross-linking aid having two or more reactive double bonds in a molecule such as 1.2 polybutadi-entry allyl cyanurate, triallyl isocyanurate, trimethylolpropane trimethacrylate may be used together with a cross-linking agent. When used, the foam becomes a uniform fine cell foam. The amount of the crosslinking aid is the same as that of the organic peroxide, and when the crosslinking aid is used, the amount of the organic peroxide is reduced. The gel fraction of a crosslinked foam of polyethylene is usually 30
To 80%. Here, the gel fraction is the percentage of the resin content excluding the sol content when immersed in 90 ° C. toluene.
The decomposition temperature of the cross-linking agent is about 160 ° C., and processing such as kneading and extrusion of the compound containing the cross-linking agent slightly varies depending on the melting point of the polyethylene used, but is usually performed at about 130 ° C.

The crosslinked expandable granular material of the present invention is a polyolefin such as polyethylene, polypropylene, ethylene-vinyl acetate copolymer or the like in which a crosslinking agent and a foaming agent are mixed, and has a larger particle size than powdered plastic. The particle size of powdered plastic is about 0.1mm and the particle size of granular material is usually 4m
m. Therefore, the particle size of the granular material is 4
0 times, but its volume and weight are the cube of 64.0
It is 00 times. Therefore, the temperature rise of the granular material is slow, the kinetic energy is large, the adhesion to the mold is delayed, and the two are clearly separated to form a skin layer, and the granular material adheres. The shape is preferably a sphere, a rod, a cube having a length substantially equal to the diameter, a cube, a rectangular parallelepiped close to a cube, or the like, which can be easily moved by rotation in a mold. The granular material adheres to the inner surface of the mold and foams, and the foam expands in a similar shape and becomes uniform fine bubbles. If the adhesion of the granular material to the mold is uneven,
The bubbles expand while deforming, which causes distortion, which causes the molded article to lose its shape. The preferred average particle size of the granular material is 2 to 10 mm, preferably 3 to 7 mm.
In the present invention, since the foamed particles adhered to the inner surface of the mold are foamed, if the size of the particles is selected and uniformly and dispersed and adhered to one layer, a core having one or two layers of foamed particles is obtained. The resulting foam has uniform and fine cells and no voids. When an inorganic powder such as talc or clay is adhered to the surface of the granular material and used, the charging due to friction of the material is prevented, and the skin material is not mixed into the foamed phase. A preferred material is a low density polyethylene having an MI of 0.5 to 10
, Preferably 1 to 3 and a density of 0.915 to 0.
930.

The foaming granular material of the present invention uses a decomposing and exothermic foaming agent such as azodicarbonamide, dinitrosopentamethylenetetramine or a mixture of these foaming agents as a foaming agent. The temperature is about 200 ° C. And the mixing amount of this foaming agent is 5 PHR or more and 40 P
HR or less, preferably 7.5 PHR or more and 30 PH
R or less. When the temperature of the mold reaches the decomposition temperature of the foaming agent and the foaming agent is in the above-described amount, the foamable granules rapidly and uniformly foam and complete the expansion while keeping the temperature substantially. When the blowing agent is 5 PHR or less, the decomposition of the blowing agent is not performed uniformly, so that heat generation is small and voids are easily formed. If the foaming agent is 40 PHR or more, it does not become a closed-cell foam. A foaming agent such as zinc stearate may be used together with the foaming agent to lower the foaming temperature, but the temperature is not lower than the decomposition temperature of the crosslinking agent. In some cases, a nucleating agent such as a filler is used together with the foaming agent to make the air bubbles fine. In the present invention, voids may be formed in the foamed phase. For this reason, a foaming agent is used extensively, and the inside of the mold is formed into a pressurized body. The foaming agent is decomposed, the cross-linked foam of polyethylene expands and fills the mold.At this time, air previously existing in the mold gathers at the center of the mold,
Escape due to the pipe inserted into the mold.

The mold used in the present invention is made of a metal material such as iron, aluminum, or brass having good thermal conductivity, or a casting. It usually consists of two parts, a side wall and an upper and lower lid. Usually, a mold for rotational molding is usually made of sheet metal, and the thickness of the mold is 2 to 3 mm. Since the mold of the present application is subjected to the foaming pressure, such a mold cannot withstand the foaming pressure, and is made of an iron plate having a thickness of 4 mm or more, or a material having strength and heat capacity equivalent to or more than that. Normal,
It is made by casting aluminum or welding an iron plate. In a mold in which an iron plate is welded, the material outside the corner is cut into an isosceles triangle having a right-angle cross section, and the distance to the inside corner of the mold is reduced.
Accordingly, it is possible to add R to the skin material at the corners of the molded body formed using this mold. The mold is provided with one or several small holes having a diameter of 3 to 10 mm for allowing air existing in the mold at the time of foaming to escape. Then, a pipe is fitted into this small hole, one end is put out, and the other end is placed as close to the center of the mold as possible. A Teflon tube is used for this pipe, and a perforated Teflon tube or a glass fiber is wrapped around the tip so that the plastic powder does not go outside. When rotational molding is performed using a mold having no small holes, voids are likely to be generated in the foamed phase. Note that voids are generated when rubber packing is used for the mold, so that packing is not usually used. There is a method in which a copper tube is welded to the outside of a mold, oil is passed through the tube, and the mold is heated and cooled. In this method, heating and cooling can be performed evenly. By increasing the heating, the corners of the compact are rounded.

The rotation of the mold is biaxial rotation, swing rotation, and the like. Uniaxial rotation is not used because a thin skin is formed. The rotation is typically 1 to 20 rpm and is a slow rotation such that no centrifugal force is applied to the material placed in the mold. This rotation normally uses both forward rotation and reverse rotation.
Heating is performed by hot air, direct fire, steam heating, oil heating, or the like. The heating temperature is set at 170 to 230 ° C., preferably 190 ° C., which is the decomposition temperature of the foaming agent.
To 210 ° C. The heating time is usually 20 to 40 minutes. When the temperature of the skin reaches the decomposition temperature of the foaming agent, each granular material foams from the part attached to the mold, and because it contains a large amount of the decomposition type foaming agent, it quickly spreads over the entire grain and expands I do. And in the present application, since the mold is kept at a uniform temperature and the foamed particles adhere to the skin at a uniform temperature and the temperature is raised,
The expansion of the granular material occurs all at once and expands from the inner wall of the mold toward the center. Decomposition of the blowing agent is an exothermic reaction, but since the blowing agent is uniformly dispersed in a large amount of polyolefin, it rapidly foams, but the temperature rise is small, and the expansion ends while maintaining the decomposition temperature of the blowing agent. And since the foaming particles are uniformly distributed and attached on the skin material and expand at the same time, the foaming particles expand through the shortest distance while maintaining a similar shape,
It becomes low-density closed cells of uniform fine bubbles, and does not generate voids or distortion. After heating, the mold is immersed in water or rapidly cooled by a shower, and the foam composite is removed from the mold. The skin rapidly cools and hardens due to water cooling. At this time, the foaming phase in the center is molten and the skin hardens while applying foaming pressure, so the surface is smooth and beautiful, and the shape of the mold elapses. The resulting molded body does not shrink. still,
When left to cool in air, the molded article becomes deformed and has a reduced impact resistance.

The foam molded article of the present invention is an energy-saving heat insulating material which has excellent heat insulating properties and does not absorb moisture even if it is placed in a humid place for a long period of time. The skin is made of a thermoplastic plastic having a thickness of 0.25 mm or more. The minimum thickness is 1/2 or more of the standard thickness. The skin covers the entire surface of the foam, and the cross-linked foam of polyolefin having a small cell diameter and a density of 0.2 g.
/ Cc, preferably around 0.03 g / cc, a composite having no voids, pinholes, or distortions in the foamed layer, and having an adhesive strength between the skin and the foam that is equal to or greater than the strength of the foam. And for the first time, with such a composite, it does not absorb as long as 50 years of the service life of the building as a thermal insulator, and therefore,
An increase in the use of energy can be suppressed without lowering the heat insulation. It is necessary that the skin covers the entire surface of the foam and the foam phase does not come into contact with air. When a hole is formed in the foam, a skin can be formed on the surface of the hole. It is possible to make a molded body having strength and good heat insulation by thinning the skin of a portion where low thermal conductivity is desired and thickening the skin of a portion requiring strength. Also, a part of the core may be thickened to improve the heat insulating property of the part. Since the foamed composite of the present invention is a sandwich structure, it is essential that the skin and the foam be well bonded, and the moisture absorption resistance is improved only after being well bonded and integrated, and the bending strength is improved. And other mechanical properties. The foam of the present invention is a semi-rigid, low density, crosslinked foam of polyolefin. Therefore, this foam does not have very high compressive strength, so it is necessary to firmly adhere to a strong skin to make a strong composite, and the adhesive strength must be higher than the strength of the foam. It is. In the case of a composite of a skin and a foam having insufficient adhesion, even if a slight scratch is formed, the composite absorbs moisture and the bending strength, compression strength, and impact strength are reduced. The thickness of the foam layer is usually 10
When the thickness is 10 mm or less, the separation between the skin and the foam layer tends to be insufficient, and it is possible to make the layer 100 mm or more. However, it is rare that the thickness is 100 mm or more. From the foamed composite of the present invention, a joined body of a skin and a foamed layer having a thickness of 5 mm is cut out, and the size thereof is, for example, 1 width.
Even if it is 0 mm in length and 100 mm in length, a knife is inserted from one end, the skin and the foam are separated from each other in half, and the skin and the foam are pulled in a direction of 180 degrees so as to separate the skin and the foam. Unable to cut foam. The foam of the present invention is a crosslinked polyolefin foam which is elastic and shock absorbing. Therefore, a product using a durable skin material is extremely durable and does not break due to impact. The foam composite board of the present invention is also characterized by having a strong skin on the side surface, which contributes to high bending, compressive strength and impact strength.
The composite of the present invention may be used for a cushion material,
At this time, the outer skin is made 1 mm or less, preferably 0.5 mm or less. Further, a soft ethylene-vinyl acetate copolymer is used as a skin, and a foam having spherical cells is used as a skin. If the thickness is 1 mm or more, the cushioning property is poor. In the present invention, a molded body of a skin and a foam is made as shown in FIG. 1. However, there is a skin as shown in FIG. 4, and there is a foam layer under the skin, and the molded body is substantially similar to the molded body in the middle. Composites with a shaped gas layer can be made. The molded body has excellent elasticity, is lightweight and inexpensive, and is used for cushioning materials, floating, and the like.
It should be noted that many large molded articles do not need to be filled with the foam up to the core. The thickness of the foamed phase of this molded product is 25 to 10
At 0 mm, this is sufficient strength.

The crosslinked foamable material is formed into a spherical shape or a rod shape,
A material coated with a non-foamed or slightly foamed material may be used as the foamable material. When this material is put into a mold and foamed, as shown in FIG. 5, the foamed layer does not foam, or a slightly foamed material section is formed, and this section is joined to the skin of the molded body to become a strength member. It becomes a composite with excellent mechanical strength. The thickness of the compartments is usually the same as the thickness of the epidermis, with a spacing of 30 to 100 mm. If this molded body is molded without using a skin material, the skin in contact with the mold becomes thin and the strength is low. This molded article is an ideal material that is lightweight, excellent in strength and heat insulation, and is used for flooring, roofing, container materials and the like. In the present invention, there is a skin, a foam layer underneath, and as shown in FIG. 6, it is possible to produce a composite having a granular material such as plastic, rubber, etc., and a granular material obtained by crushing the foam composite in the middle. I can do it. In this molding, the powdered plastic, the crosslinked foamable granules, and the granules such as plastic, rubber, and waste such as the present foamed composite, which are larger in size than the crosslinked foamable granules, are put into a mold and rotated. It is made by heating while heating, and large-sized wastes etc. gather at the center of the molded body due to this, and a strong and reasonably heat-insulating molded body can be made, and plastics, rubber, and waste of this foam can be used. It is suitable. In this technique, it is possible to use crosslinked polyethylene waste, FRP waste, and waste of the composite which cannot be used as a plastic waste by other methods. The amount of the large-sized granules used is 40 to 70% of the weight of the compact. This molded body has good heat insulation because of the foam phase under the skin, and does not break even when subjected to impact.
Used for architectural formwork, basement, water column, board, etc. In the present invention, industrial waste can be used as the material for the skin and the material of the crosslinked expandable granular material. Even if a small amount of mud or sand enters the skin material and the crosslinked expandable granular material of the present invention, it does not affect the molding. In addition, the foaming of the present invention is based on crosslinked foamable granules, and a large number of small particles foam in an aggregated state to form a foamed layer. Therefore, for example, even if a small amount of particles having poor foamability are mixed, it is fine. A thin non-waste skin may be attached to the skin of the composite molded with plastic waste, and the thickness is usually 0.1 to 0.5 mm.
Thus, the disadvantage of using plastic waste is eliminated. In the present invention, a flame retardant is added to one or both of the skin and the foam layer and molded to obtain a molded article having flame retardancy. The molded article of the present invention can be formed by pasting a plastic film, a composite film, a metal foil, and a thin metal sheet in a mold, and then molding the molded article with these objects adhered to the surface of the molded article. . Filler, glass fiber, carbon black, stainless steel fiber or the like can be added to the skin of the molded article of the present invention to enhance the skin and prevent generation of static electricity. Further, a molded article having an uneven surface can be obtained by using an uneven mold.

In the present invention, a metal fitting is attached to the mold by making a small hole, and bolts, nuts, pipes, hooks, and the like can be embedded in the foam composite. For example, in order to embed a bolt, the bolt is inserted into the inside of a mold, both ends of the bolt are passed through small holes of the mold, and a nut is attached to a tip of the bolt to form the bolt. The heat is transmitted from the nut outside the mold to the bolt and heated to form a skin on the surface of the bolt, and the skin is bonded to the skin and the foam layer of the foamed composite, thereby firmly fixing the bolt. Therefore, there is a part of the metal fitting outside the mold, and it is necessary to supply heat to the metal fitting from there. And with this metal fitting, strong connection between the composite molded bodies or other objects can be easily performed. Also, if you make a skin perpendicular to the board using a metal pipe on the foam board, this skin is connected to the top and bottom skins of the board, and it is well bonded to the foam phase, so this foam board Significantly improves compression resistance, impact resistance, and bending strength. In this manner, the foam composite of the present invention can be provided with a metal fitting, and the metal fitting can be used to form a right-angled hole in a plate having a skin having a thickness of 1.0 mm or more. Is provided, even if water or air is passed through the pores for a long period of time, the foam does not absorb water and moisture, and the heat insulating property does not decrease. This hole is used for a heat insulation box for storing hot water and cold water using nighttime power or solar heat.

It is possible to form a convex portion on the molded product of the present invention, form a concave portion or a hole of the same size in this molded product or another molded product, and connect these to connect the molded products. Since the molded article of the present invention has a smooth skin on an elastic core, this molded article can be bonded by uneven bonding, and can be bonded while maintaining strong and airtightness. Since the bolt is buried in the molded article of the present invention, the bolt can be buried and bound with a wire or the like to complete this connection. For example, a floating pier can be constructed by this connection and then combined to form a bridge.
In addition, a plate of 1 × 2 m and a thickness of 50 mm can be made, and this can be unevenly combined to form a baseball stadium fence. This board is self-supporting, makes a horizontal plate for holding down, just stops on it, it absorbs shock well, and it does not hurt even if hit by a player. Although the plate-shaped body of the present invention is often used in refrigerated warehouses and the like,
Walls and ceilings that do not require strength can be used simply by connecting the plate-like body unevenly, and the holding plate is used only where strength is required.
The same applies to freezing rooms of automobiles, trains, ships, and the like. The connection between the convex part of the molded body of the present invention and the hole of the molded body is easy to enter into the hole by slightly tapering the tip of the convex part, and a step is formed at the place where it enters and exits, and once it enters, it is easy Make the structure that does not come off.
Since the present molded body is composed of the skin and the core, it is easy to be connected by the elasticity of the core, and the connection is not easily released by the strong skin.

According to the method of the present invention, a long cylindrical or semi-cylindrical body is made, and a male screw is attached to one end and a female screw is attached to the other end.
This can be combined (two semi-cylindrical bodies are combined) and used as a heat retaining pipe for a hot spring pipe. Since this pipe has strength and elasticity, it can be used simply by joining. This pipe can be used as a duct by making it flame-retardant, and in order to complete the flame-retardancy, a thin metal cover such as tinplate is hung. Some gaps may be created.

According to the present invention, a long semi-cylindrical body is formed, and irregularities are formed at both ends thereof so that the semi-cylindrical body can be joined, and a weight is attached and sunk.
The concave surface of the semi-cylindrical body faces offshore so that the water surface is at the center of the concave surface. Even if the ship sinks and the oil rushes in, the oil will not be able to pass over this half-cylinder or get under it, so it will collect at this half-cylinder. In this method, oil recovery is extremely easy. A long body to which this connection can be made cannot be made except by the method of the present application.

When forming a foam board by the method of the present invention, a hole for passing a bolt is formed at the time of molding, a hole having a skin is formed, a nut is embedded in a different place, and the bolt is formed in the hole using six such plates. It can be made into a watertight box by connecting it with a nut of another plate. The foam board of the present invention can easily be made into a watertight box simply by tightening bolts. Since it is lightweight, durable, heat-insulating, and easy to disassemble, assemble, and wash with water, it is a convenient container for fish, especially for live fish.

A box-shaped frame is formed from an iron angle, a foam plate is arranged on the frame, holes are formed in the angle, and pressure is applied to the foam plate with bolts. It can be made into an air-tight heat-insulated box by using packing made of foam or plastic. The molded body of this technology can be formed by cooling the skin while applying pressure at a high temperature to the core in the mold, so that the plate is extremely smooth and finished with good dimensional accuracy, and thus can be used in this way. Instead of a box with only six boards,
For example, a box using 24 sheets of 4 sheets each, or a box having a larger shape can be used.

The molded article of the present invention has a sandwich structure, a cross-linked foam of impact-resistant polyolefin in the center, and is integrally bonded to upper and lower skins, so that it is not broken by impact.
Of course, the skin of the part hit by the impact may be broken, but the foam of the core and the skin on the opposite side are not broken at all. Making a big drum using this property,
A stainless steel drum containing radioactive waste solidified with glass is placed in it, and rubber or oil that flows at high temperature but does not flow at room temperature is sealed between these two drums, and sealed for storage of radioactive waste. Never rust for many years. If a gasoline tank is made of this material, it will not break due to impact when a car crashes, so no fire will occur.

By embedding a bolt or a nut in the center of the molded body, the molded body can be easily fixed to another object. For example, a chair is molded, a nut is embedded in the molded body, a bolt is attached to the vehicle body, and the chair is attached to the vehicle body with the bolt and the nut. Since the chair of the present application is made of only the plastic skin and the foam, even if a collision accident occurs on an aircraft or a bullet train, it does not lead to personal injury. Of course, in this case, it is necessary to use this material also for floors and walls. If a round table is made and nuts are filled, it can be assembled very easily and is convenient. Since the molded article of the present invention is light and strong, it can be easily cleaned. Also, the headrest is the same, and this method can be used in various ways.

A portion of a pipe that dries or gets wet due to the ebb and flow of seawater, such as an iron pipe in the sea, is extremely rust easily. Moreover, this part is often damaged by ships. By the method of the present application, a long semi-cylindrical body having the same inner diameter as the outer diameter of the iron pipe is made, a sealing material of butyl rubber, for example, is placed on the inner surface thereof, two of these are put on the iron pipe, and one end of the pipe in the water is placed in the water. Pressure from the outside of the steel pipe, the seawater on the iron pipe is expelled to the top with a sealing material, then pressure is applied to the next part sequentially, and this is repeated until the other end,
Seawater and air are forced to the top and almost disappear. After this, the pipe will not rust. This is because the molded body of the present application has elasticity, so that a uniform pressure can be applied with the butyl rubber sealing material, and seawater and oxygen disappear from the surface of the iron pipe. It can also be constructed. According to the method of the present invention, a long plate-like body having irregularities on four sides is formed, and this is bent and joined into a circular shape. You can make a combination of shapes. This cylindrical body also has irregularities on the upper and lower parts, and it is possible to make a bottom and a lid using this to make a container. Since the molded article of the present application is composed of a smooth skin and a core having good elasticity and has good moldability, it is possible to form a strong joint simply by joining it, and there is no water leakage. Although a sealing material or an adhesive may be used for the contact portion, it is not usually used. This cylindrical body becomes a cylindrical container, and the half-cylindrical body connected to the half-cylinder also serves as a waterproof wall of the tunnel. Next, examples of the present invention will be described. [Example 1]

High density polyethylene, density 0.96 g / c
c, a powder having a storage elastic modulus of 1 × 10 ⁴ (Pa) at an angular frequency of 1 (rad / s) at 190 ° C., a low-density polyethylene, a density of 0.92 g / cc, and a dicumyl peroxide of MI1.5. .8PHR, azodicarbonamide 15P
HR was kneaded into a cube with a side of 5 mm.
The amount shown in the table was put into a mold (wall thickness 5 mm) of 200 × 20025 mm in inner method. This mold has a diameter of 5mm at the center of the bottom.
There was a hole, a Teflon tube was attached to this, the tip inside the mold was covered with a small hole in the Teflon sheet, one end was positioned substantially in the center of the mold, and the other end was out. . This was heated at 230 ° C. for 30 minutes using a biaxially rotating hot air heating molding machine. The rotation speed was 10 rpm for one and 5 rpm for the other. The temperature of the removed mold is 200 ° C
Then, this was quenched in water and a molded body was taken out. The obtained molded body is a molded body as shown in FIG. 1 according to the shape of a mold having a smooth surface, without burrs, the skin and the foam are clearly separated,
The foaming phase is composed of two layers of granular material, and the foaming phase and the skin are well adhered to each other. The properties are as shown in Table 1. It is excellent in heat insulation, moisture absorption resistance, mechanical strength, and does not shrink over time. Was something. The amount of water absorption was determined by heating the molded body to 90 ° C
After soaking for days, the increase in weight was measured.

[Table 1] [Example 2]

In No. 2 of Example 1, 0.5 PHR of dicumyl peroxide, 0.5 PHR of trimethylolpropane triacrylate, and azodicarbonamide were added to low-density polyethylene instead of high-density polyethylene powder. 0PHR, foaming aid zinc stearate 0.1
100 g of the fine granules obtained by kneading the PHR into a cube having a side of 1.0 mm and 35 g of the foaming compound of Example 1 were added.
Rotational molding was performed in the same manner as in Example 1. As shown in FIG. 2, the obtained molded body had a foamed skin, and had a density of 0.6.
5 g / cc, skin thickness 2.9 mm, minimum skin thickness 2.
4mm, foam density 0.033g / cc, cell diameter 0.4
mm, the thermal conductivity of the molded body is 0.28 Kcal / mh ° C.
The water absorption rate was 0.01% and there was no void. The skin and the foam were firmly adhered to each other, and the heat insulating property was extremely good. [Example 3]

The fine granules for the skin of Example 2 were weighed to 75 g, and instead, 50 g of the high-density polyethylene powder of Example 1 was charged, and this was rotationally molded in the same manner as in Example 1. The skin thickness of the obtained molded body is 2.4 mm, and the minimum thickness is 2.0 mm.
mm, foam density 0.033 g / cc, foam cell diameter 0.4 mm, thermal conductivity 0.36 Kcal / mh ° C, water absorption 0.01%, no voids and distortion in the core, and the skin is foamed The molded body as shown in FIG. 3 was composed of two phases with an unfoamed skin, and had good heat insulating properties, a smooth and beautiful surface. [Example 4]

In the center of the 2000 × 500 mm side of a mold for forming a molded body of 2000 × 1000 × 500 mm,
A projection of 00 × 100 × 50 mm was made and a recess of the same dimensions was made on the opposite side. 21 Kg of the powdered plastic of Example 1 and 15 Kg of the foaming compound were placed in this mold and molded under the same rotation conditions and temperature. The surface temperature of the removed mold was 205 ° C., and the completed molded body was in the shape of the mold, and the material used was small. Therefore, the skin was 3 mm, the phase of the foam was about 100 mm, and the center of the molded body was about 1800 ×
There is a 800 x 300 hollow part, there is strength, buoyancy,
It was never overturned on the water, and was suitable as a floating pier that could be connected using unevenness. Since both the convex portion and the concave portion of the molded body were made of the skin and the foam, they were extremely strongly bonded, and the bonded product was not easily removed. only,
As a precautionary measure, a bolt was embedded in the molded body, and this was connected with a wire or the like. [Example 5]

The foamed compound of Example 1 was 4 mm in diameter.
, And was coated thereon with the low-density foaming compound of Example 2 to a thickness of 2 mm, which was cut into a length of 8 mm. 50 parts of the compound and the skin material of Example 1 were used.
It was placed in a 0 × 500 × 25 mm mold and heated and foamed under the same conditions as in Example 1. As shown in FIG. 5, the obtained foamed composite has vertical and horizontal sections with a double expansion ratio in the core, a thickness of about 3 mm, and foamed particles arranged in two stages. It was a durable thing that a person wearing high heels could walk on with a heat insulating flooring material of about 30 mm and having extremely good compression strength and impact strength. [Example 6]

The size is 2000 × 1000 × 50 mm, and 2000 × 20 × 10 m
There are concave and convex m
21 kg of the powdered plastic of Example 1 and 29 kg of the foaming compound were added thereto, and a rubber particle (with an average particle diameter of about 1) was added thereto.
(0 mm), and 50 Kg was added thereto, followed by rotational molding in the same manner as in Example 4. The obtained molded body is a molded body as shown in Fig. 6, which is durable, self-supporting, does not break even when subjected to impact, has good shock absorption and weather resistance, and is constructed without causing injury to people even if it hits However, it was easy to simply hold the upper and lower parts to the holding plate, and it was the best one for a baseball stadium. [Example 7]

26 kg of the foaming compound for the skin of Example 2 and 11.5 kg of the foaming compound for the core of Example 2 were placed in a 2000 × 1000 × 200 mm mold, and were rotationally molded in the same manner as in Example 1. The obtained molded body had a skin thickness of 0.
5mm, density 0.5g / cc, foam thickness is about 50
mm, density 0.05g / cc, about 1800x in the center
It had a hollow part of 800 x 100 mm, was durable, had good cushioning and heat insulating properties, could be washed with water, could be repeatedly disinfected, and was good as a hospital mattress for infection prevention. Example 8

An iron angle was assembled into a box shape, and a 1000 × 1000 × 1000 mm space was formed using four 1050 × 1000 × 50 mm foam composite plates. In this, a 1100 × 1100 × 50 mm foam composite plate is used as a packing by placing a 2 mm thick crosslinked polyethylene foam sheet (expansion ratio 5 times) on all portions where the plate and the plate are in contact with each other, A screw hole was made in the angle, and pressure was applied to the foam plate with a bolt to compress the packing so as to be airtight. The finished heat insulation box has no water leakage, is durable, has excellent heat insulation, is easy to disassemble and assemble, and can be used repeatedly.It is suitable as a live fish transport box and does not deteriorate even after long-term use. Met. [Example 9]

Through-holes with skins are provided at the time of molding on the right and upper sides of the 1000 face of the foam plate of 1050 × 1000 × 50 mm, and the 1000 × 50 mm face on the opposite left side and the 1050 × 50 mm upper and lower faces are formed. Four plates with two nuts embedded at both ends of the surface are made and connected with bolts to form four sides, 1000 × 1000 × 10
A space of 00 mm was created. 1100 × 110 above and below
A heat insulating box was made by bolting a 0 × 50 mm foam plate having eight through holes on the surface as a bottom and a lid. This box was lightweight, durable and excellent in heat insulation, was easy to disassemble and assemble, could be washed with water, and was extremely useful as an insulation box for transporting food. [Example 10]

A 500 × 500 × 50 mm plate is 500 ×
A molding having 500 × 30 × 10 mm protrusions formed on two adjacent surfaces of 50 mm and concave portions of the same dimensions provided on the remaining two surfaces of 500 × 50 mm was molded using the powdered plastic of Example 1 and a foaming compound. Thus, a foam composite having a foam density of 0.03 g / cc with a skin of 2 mm was produced. This insulation board can be easily fitted, is self-supporting just by fitting, is firmly connected, does not come off easily, has excellent heat insulation and is good as a floor material, wall material and ceiling material for a freezer warehouse. Met. [Example 11]

A stainless steel drum containing radioactive waste and hardened with glass has a diameter of 200 mm and a height of 200 mm.
A large drum was made of a compact consisting of skin and foam (skin thickness 5 mm, foam density 0.12 g / cc, thickness 50 mm). Three 100 mm-thick bricks were placed on the bottom of the container, and a radioactive waste drum was placed thereon. The gap between the container and the drum was filled with polyisobutylene which did not flow at room temperature but flowed at 100 ° C. Then, a lid made of the same foamed composite was closed, a hole was made in the lid so that there was no gap at the top, and polyisobutylene was injected again. This container protects the stainless steel drum with four layers of skin material, foam, skin material, and rubber. It does not break even if it receives an impact and does not enter water at all. It did not rust at all even after passing through, and even if it was subjected to an impact, only the outermost skin was broken, and the contents did not change. [Example 12]

A semi-cylindrical foamed composite having a diameter of 1,000 mm, a length of 2,000 mm and a thickness of 30 mm (skin 3 mm, foaming ratio 10 times, thickness 24 mm) was produced. The apparent density is 0.1
It was 4 g / cc. Protrusions and recesses having a thickness of 10 mm and a length of 10 mm are formed on the circumference at both ends in the length direction of this half cylinder so that they can be connected with each other, and within 25 mm from both ends and the circumference end. Four 10 mm bolts were buried in the place where they entered, and the structure was partially exposed. After the connection, the bolts and bolts were fixed with wires. This semi-cylindrical oil dike was submerged halfway with a weight, and was placed concavely offshore so that the water surface was at the center of the cylinder. In this dike, oil accumulates in this concave part, cannot pass through from above and below, and
It was easy to recover oil, and it was not necessary to use it twice in an extremely excellent oil dike. Example 13

A half-cylinder made of a foamed composite having a diameter of 300 mm and a length of 2000 mm was made with a thread cut at both ends, and when two were combined, the structure was such that these screws were sequentially connected. This cylinder is a composite of 2 mm skin and 30 times foam and is 46 mm thick. It is airtight just by screwing, it does not enter water at all, it does not come off easily, it has good heat insulation,
It was strong, easy to install and remove, and extremely convenient as a hot spring pipe. When this duct was made to be flame-retardant, and it was covered with tinplate or the like, it became more flame-retardant. However, when the duct was installed with a gap between it and the cylinder, the flame-retardancy became complete. [Example 14]

A heat insulating tank having a height of 2,000 mm, a width of 700 mm and a depth of 400 mm is covered with a skin of 3 mm, a foam of 30 times,
It was made with a foam thickness of 44 mm. It consists of a container and a lid, and the lid has holes at the four corners of the flat plate and is bolted to the container.
A hot water inlet was provided at the top, and a hot water outlet was provided at a location 10 mm above the bottom. 3 hot water inlets and outlets
With a plastic skin of mm thickness, inner diameter is 25mm
I made it. A heater was attached to the lower half of this container so that it could be used at any time. This insulated container did not take up much space even when placed under the eaves, had a simple structure and had good heat insulating properties, and did not deteriorate even after years of use. [Example 15]

A foam composite having a thickness of 100 mm (skin 2 m
m, foaming ratio 30 times, thickness 94mm)
He built a chair with both elbows integrated with a nut in the center of the lower part of the seat. This chair is lightweight, cushioning and self-supporting, and is made of a foam composite except for nuts, so if it is used in a chair for a vehicle such as an aircraft or a Shinkansen, no one will be hurt in the event of an accident. there were. [Example 16]

A two-seater boat having a skin thickness of 2 mm and a foam density of 0.03 g / cc was produced by the method of the present invention by the method of [Example 1]. This boat weighed 10 kg, was lightweight and could be carried by one person, did not sink even when capsized, and could be returned to normal by one person in water, making it extremely suitable for beginners. Further, metal fittings are attached to the boat, surf-in and the like, and oars and the like are attached. [Example 17]

A long semi-cylindrical body having the same inner diameter as the outer diameter of the iron pipe is formed by the method of the present invention in a portion of the underwater iron pipe which is dried or wet by the ebb and flow of seawater, and a butyl rubber sealing material is further formed thereon. (Thickness: 5 mm), put the two pieces on a pipe, apply pressure to the entire circumference from the outside of one end of the molded body in water, expel seawater and air on the pipe to the top, and then Was sequentially applied to this part, and this was repeated until the other end. By this work, the seawater and air that had been on the pipe were expelled by the sealing material, after which the pipe rust stopped. The molded article was strong and shock-absorbing, so that it was not damaged even when the vessel collided. [Example 18]

By the method of [Example 1], a long plate having irregularities on four sides and capable of being joined was produced, this was bent into a circular shape and both ends were joined, and then the next long body was bent first. The tip was joined while being joined to the object, and the tip was joined. This was repeated to form a long cylindrical shape, and a disk having a concave and a convex on the circumference was joined to the bottom and the lid. This molded article had no water leakage, had heat insulating properties and elasticity, and did not come off once bonded, so that it could be used as a container for brewing. Also, the half cylinder made by this method could be used as a waterproof material for a tunnel. [Example 19]

500 × 500 × 25 manufactured by the method of the present application
A 300 × 25 mm projection was formed at the center of each side of the foamed plate having a thickness of mm. (A) 590 x 300 x 25 mm foamed plate, 300 mm
20mm away from the edge on one side
A hole of 0x25mm was made, and the other side of 300mm was cut off 50x50mm from the top and bottom, and 200x in the center.
A 25 mm convex portion was formed, and a 300 × 25 mm hole was formed in the center of the lower side at a distance of 20 mm from the end. (B) The convex portions of A and B are slightly narrower toward the tip, so that they can be easily inserted into the hole, and there is a step at the position where the hole has been completely inserted. When B is fitted on each side of A and the protrusions and holes of B are respectively connected, 500 × 500 × 300 mm
This box has strength and heat insulation, and can be easily assembled and disassembled. For the trip, put the fish and use it as a box,
The return can be brought back on a plate, which is extremely preferable as a fish box.

[Effects of the Invention] As described above, a thick plastic mold is used, and powdered plastic and foamable granules larger than this are used. 15% of mold volume including compound
Heat it evenly from the outside while rotating it biaxially so as not to apply centrifugal force to generate a skin with a uniform thickness, and form a foamed granular material on this skin. The temperature of the mold and the temperature of the skin material are set to the decomposition temperature of the foaming agent, and the foam is blown all at once, and then rapidly cooled. According to this production method, a molded body composed of a skin and a foam can be produced in one step, and the molded body is lightweight, strong, has excellent heat insulating properties, does not absorb moisture to reduce heat insulating properties, and has cushioning properties. Is very useful because

[Brief description of the drawings]

Fig. 1 Skin and foam insulation

Fig. 2 Foam skin and foam insulation

FIG. 3 Insulation material of skin, foam skin and foam

FIG. 4 is a heat insulating material comprising a skin, a foam, and a hollow portion.

FIG. 5: Insulation material consisting of skin, foam and compartment

FIG. 6 is a thermal insulator made of a granular material of skin, foam, rubber, and plastic.

[Explanation of symbols]

 (1) Skin (2) Foam (3) Foamed skin (4) Hollow (5) Compartment (6) Rubber and plastic granules

──────────────────────────────────────────────────の Continued on the front page (51) Int.Cl. ⁷ Identification symbol FI theme coat ゛ (reference) // B29C 44/00 B29C 67/22 B29K 105: 04 105: 24 F term (reference) 4F074 AA05 AA16 AA18 AA20 AA97 AA98 AC02 AC06 AE01 AE04 AG01 AG06 AG10 AG12 BA01 BA13 BA28 BB02 BB25 BB27 CA28 CC04X CC04Y CC05Z CC06Y CC30W CC32Y CC33W CC43 CC44 CC46 CC47 CC62 CD07 DA02 DA03 DA07 DA08 DA23 DA32 DA33 DA34 DA05 A03 AB03 AB03 AB03 AB03 AB25 AC01 AC04 AD03 AD05 AD16 AG03 AG07 AG20 AH17 AH59 AR06 FB01 FB11 FB22 FF01 FF05 FF06 FN12 FN15 FQ15 4F212 AA03 AA04 AA50 AB01 AB02 AB03 AB05 AB11 AB12 AB18 AB25 AC04 AG03 AG05 AG20 AG23 AG28 AH07 AUH UAH UN06 UN08 4J002 AA00W AA01W AA02W BB00X BB03W BB03X DA038 EK007 EK037 EQ016 FA048 FD018 FD099 FD139 FD147 FD159 FD189 FD326

Claims (45)

[Claims] 1. A plastic powder or fine granules and a crosslinked foamable polyolefin granule containing a decomposing and exothermic foaming agent are put into a mold so that the material can move, and heated while rotating, A skin is made, a foamable granule is adhered on the skin, and further heated to a mold temperature and then a skin temperature to a decomposition temperature of a foaming agent, and the foaming agent is decomposed and expanded to form a polyhedral foam. And then cooling the mixture. 2. A method according to claim 1, wherein a plastic powder or fine granules and a crosslinked foamable polyolefin blended with a decomposing and exothermic blowing agent are mixed with the powder or fine granules so that the material can move in a mold. Put it in a thick mold, heat it evenly while rotating, make a skin of uniform thickness, distribute and adhere the expandable granules evenly on the skin, and further heat it, The temperature and then the temperature of the epidermis are set to the decomposition temperature of the foaming agent, and the foaming agent is simultaneously decomposed and expanded to form a polyhedral foam,
A method for producing a foamed composite, comprising filling in a mold and then cooling. 3. The method according to claim 1, wherein a thermoplastic resin powder or a powder that does not completely cure the thermosetting resin is used as the plastic powder. 4. The method according to claim 1, wherein the crosslinked expandable granules are a mixture of polyolefin and an organic peroxide and a foaming agent, or a mixture of polyolefin and a foaming agent. A method using a granular material irradiated with radiation. 5. The polyolefin according to claim 1, wherein the polyolefin is 0.2 to 1.2 PHR of an organic peroxide and 5 to 40 P
A method using a crosslinked expandable granule mixed with an HR blowing agent. 6. The method according to claim 1, wherein a crosslinking aid is used together with a crosslinking agent. 7. The method according to claim 1, wherein a foaming aid is used together with a foaming agent. 8. The method according to claim 1, wherein the apparent volume of the material mixture to be placed in the mold is not more than 85% of the volume of the mold. 9. A method using a granular material. 10. The foamed composite according to claim 1, wherein the crosslinked foamable granules are adhered on the skin layer in a single layer and foamed, and the foamed granules are formed in one or two layers. How to manufacture. 11. A method according to claim 1, wherein the powdered plastic has a storage elastic modulus of 1 × 10 ³ (Pa) or more at an angular frequency of 1 (rad / s) at 190 ° C. 12. The method according to claim 1, wherein a metal plate having a thickness of 4 mm or more or a metal body having strength and heat capacity equivalent to or more than that is used for the mold. 13. A method according to claim 1, wherein a metal mold made by welding an iron plate of 5 mm or more is used. 14. A method of manufacturing a foamed composite according to claim 1, wherein the amount of heat flowing into the corners of the mold is increased so as to add a radius to the middle corner of the skin material of the completed molded body. Method. 15. The method according to claim 1, wherein one or several small holes are made in the mold, a pipe is attached to the small hole, one end is placed in the center of the mold, and the other end is taken out. A method for producing a foamed composite in which gas is released from a mold. 16. The method for producing a foamed composite according to claim 1, wherein the mold is heated by hot air, an open flame, steam, and oil passed through a metal pipe in close contact with the mold. 17. The method according to claim 1, wherein the rotation of the mold is performed by biaxial rotation or swing rotation, and the rotation speed is 1 to 20 rpm.
How to make m. 18. The method according to claim 1, wherein the temperature of the mold is 17
A molding method in which foaming is performed at 0 to 230 ° C. so that the adhesive strength between the skin and the foam is equal to or higher than the strength of the foam. 19. The method according to claim 1, wherein a foaming agent of 0.1 to 2 PHR is mixed with the plastic skin material and molded to produce a molded body of the foam foamed into spherical cells. 20. The method according to claim 1, wherein a filler, a fiber, a carbon black, a stainless steel wire, a fungicide, an antibacterial agent, a pigment and the like are mixed with the plastic powder, and the mixture is molded. A method for producing a molded article containing the same. 21. The method according to claim 1, wherein two or more plastic powders or fine particles having different sizes are used to produce a molded article having two layers or two or more skin layers. 22. The method according to claim 1, wherein a halogen-based or non-halogen-based flame retardant is added to one or both of the skin material and the foam material to produce a flame-retardant composite. 23. The method for producing a composite according to claim 1, wherein plastic waste is used for one or both of the skin material and the foam material. 24. The method for producing a composite according to claim 1, wherein plastic waste is used for the skin, and a thin plastic skin that is not a waste is formed thereon. 25. The method according to claim 1, wherein the foamed composite has a cushioning property with a skin of 1 mm or less and a foam density of 0.1 g / cc or less. 26. The method according to claim 1, wherein a small amount of material is placed in the mold, and a foamed composite having a gas phase substantially similar to the mold is formed at the center of the mold. 27. A section of a non-foamed or slightly foamed material according to claim 1, wherein the cross-linked foamed material is coated with a non-foamed or slightly foamed material. For producing a foamed composite having a texture. 28. The method according to claim 1, wherein particles of rubber, plastic, or a composite material such as rubber, plastic, or the like larger than the particles are added together with the powder and the particles to be foamed, and the particles are heated while rotating. A method for producing a foamed composite in which these particles are located at the center of the molded body and are fixed with a foam. 29. The method according to claim 1, wherein a metal fitting is attached to a mold, and a skin is also formed on the surface of the metal fitting to produce a foamed composite. 30. A method for constructing a foamed composite in which holes having skins are provided at four corners of a plate-like body produced by the method of claim 1, and the holes are bolted to a support. 31. When producing a foamed composite according to the method of claim 1, a protruding portion or a protruding portion having a step at the root of the protruding portion is formed on one of the foamed composites to form the same or different molded products. A method of joining a foamed composite, wherein a recess or a hole having the same size is formed and joined. 32. A method of connecting a long foam composite, comprising forming a long semi-cylindrical body or a cylindrical body having a male screw and a female screw at both ends by the method of [1], and screwing the formed body. 33. A method for producing a foamed composite in which a part of the skin is made thinner and a part of the skin is made thicker by the method of [1]. 34. A method for producing a foamed composite in which a part of the core is thinned and a part of the core is thickened by the method of claim 1. 35. A method of manufacturing an assembly in which a nut is embedded and a foamed composite plate having bolt holes is formed by the method of claim 1, and this is assembled. 36. A method for producing a foamed composite in which a bolt or a nut is buried substantially in the center of a molded article according to the method of claim 1 and the bolt or the nut is joined to another object. 37. In producing a plate of a molded article by the method of claim 1, a right-angled hole is provided, and a skin is formed on the surface of the hole.
A method for producing a foamed composite in which the skin is fused to the skin of the molded body and the foam. 38. A plate-like body is produced by the method of [1], and in an assembly obtained by assembling the plate-like body, pressure is applied by using packing of rubber or foamed plastic at a contact portion between the plates. Manufacturing method of foam composite assembly to be assembled. 39. The method according to claim 1, wherein a molded body made of a high-density polyethylene skin and a foam having a density of 0.1 g / cc or less is produced, and is not broken even if a car collides. A method for producing a gasoline tank made of a foamed composite that does not generate. 40. A rubber composite or oil which flows when heated between the container and the object to be rusted, but which does not flow at room temperature. Put the lid on to prevent rust. 41. A long semi-cylindrical body according to the method of claim 1,
A method of blocking oil that creates a molded body that can be joined at both ends, connects them, attaches a weight, sinks half, floats half, and turns concave to offshore. 42. A method according to claim 1, wherein a thin object such as a plastic film, a plastic composite film, a thin metal plate, a metal foil or the like is adhered and molded in a mold, and these thin objects adhere to the surface. A method for producing a foamed molded article. 43. A long semi-cylindrical body is produced by the method of [1], a sealing material is placed on the inner surface thereof, and these two are put on a pipe which is wet or dry by the ebb and flow of seawater. A method for preventing corrosion of a metal pipe, wherein pressure is applied from outside the half-cylinder to cover the pipe surface with a sealing material. 44. A plate having four irregularities on the four sides formed by the method of claim 1 is bent into a cylindrical shape or a partially chipped cylindrical shape, and the next plate is rounded while being joined. Connect to
A method for producing a cylindrical body that repeats this or a cylindrical body that is partially missing. 45. The foam composite produced by the method of claim 1 having a skin of 1 to 4 mm, a density of the foam of 0.02 to 0.14 g / cc, and even if it is overturned on water alone. Elevating material for people such as boats and surf-ins that can be easily fixed.