JPH11138647A - Manufacture of hollow construction - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a method of a hollow construction that can remove a core readily and improve productivity. SOLUTION: This comprises the steps of a first process for winding reinforcing fiber 13 round the outer peripheral surface of a core 11 consisting of a biodegradable polymer, a second process for applying and then curing uncured resin or fused resin 14 to the reinforcing fiber 13 and forming a resin layer 12 reinforced with the reinforcing fiber 13 round the outer peripheral surface of the core 11, and a third process for introducing and subsequently decomposing a biological active substance 17 to the core 11 consisting of the biodegradable polymer.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for producing a composite product reinforced with reinforcing fibers, for example, a hollow structure such as a container or a tubular body.

[0002]

2. Description of the Related Art Carbon fiber reinforced plastic (hereinafter referred to as CF)
RP), glass fiber reinforced plastic (hereinafter, G
Composite products reinforced with reinforcing fibers such as FRP)
For example, when manufacturing a hollow structure having an undercut, a method shown in FIG. 5 is conventionally used.

[0003] That is, a metal split mandrel 1 consisting of an outer shell 1a shaped like a shape to be formed and a core 1b is prepared, and CRFP or GFRP is laminated on the outer peripheral surface of the outer shell 1a of the split mandrel 1. The reinforcing fiber reinforced resin layer 2 is formed. After the reinforcing fiber reinforced resin layer 2 is heated or cured at room temperature, the outer shell 1 of the split mandrel 1
The hollow structure 3 is formed by mechanically decomposing (separating) the core material 1a and the core material 1b and extracting the hollow material from the inside of the reinforcing fiber reinforced resin layer 2.

In the case where the shape of the hollow structure to be molded is complicated and it is difficult to mechanically disassemble and remove the metal mandrel after molding, the mandrel is formed of a metal having a low melting point. As described above, after the CRFP or GFRP is laminated on the outer peripheral surface of the mandrel to form a reinforcing fiber reinforced resin layer and cured at room temperature, the mandrel is heated at an appropriate temperature to melt and remove the mandrel. .

[0005] Further, the mandrel is formed of a material that is melted by a drug, or formed of collapsible gypsum.
A method of crushing and removing collapsed gypsum is also known. As shown in FIG. 6A, the manufacturing method as described above
As shown in FIG. 4B, the cylindrical member 5 having bent portions 5a at both ends as shown in FIG.

[0006]

However, the above-mentioned split mandrel is difficult to manufacture and causes an increase in cost. Further, when the shape is complicated, it is difficult to manufacture and separate the molded mandrel after molding, and it is impossible to form a molded product. It may be deformed or damaged by excessive force.

[0007] Further, the method of heating and melting the mandrel, the method of melting and removing the mandrel with a chemical, and the method of crushing and removing collapsible gypsum all require man-hours. In some cases, it is difficult to completely remove all corners. When the core is made of aluminum, sodium hydroxide is used as a solvent for the chemical. However, it is not preferable because the cost of dissolving it as a waste liquid is high.

The present invention has been made in view of the above circumstances, and an object of the present invention is to easily remove a core as a mandrel after molding even a hollow structure having a complicated shape. It is an object of the present invention to provide a method of manufacturing a hollow structure which can improve productivity and does not apply excessive force to the hollow structure when removing the core, and can prevent deformation and breakage. .

[0009]

In order to achieve the above object, the present invention has a first step of winding a reinforcing fiber around an outer peripheral surface of a core made of a biodegradable polymer; A second step of applying an uncured resin or a molten resin to the reinforcing fibers and curing the resin to form a resin layer reinforced with reinforcing fibers on the outer peripheral surface of the core; and a core comprising the biodegradable polymer. And a third step of introducing and decomposing a biochemically active substance into the hollow structure.

[0010] A second step of winding and laminating a prepreg on the outer peripheral surface of a core made of a biodegradable polymer, and heating the core having the prepreg wound thereon to form a resin in the prepreg A second step of forming a resin layer reinforced with reinforcing fibers on the outer peripheral surface of the core, and a third step of introducing a biochemically active substance into the core made of the biodegradable polymer to decompose the core. And a method for manufacturing a hollow structure.

In a third aspect, a first step of winding a reinforcing fiber around an outer peripheral surface of a core made of a biodegradable polymer, and a step of storing the core wound with the reinforcing fiber in a mold, and A second step of injecting an uncured resin or a molten resin into a mold to form a resin layer reinforced with reinforcing fibers on the outer peripheral surface of the core, and taking out the resin layer reinforced with reinforcing fibers from the molding die And introducing a biochemically active substance into a core made of a biodegradable polymer to decompose the core.

By manufacturing the core from a biodegradable polymer, the hollow structure to be formed can be easily manufactured even if it has a complicated shape.
It can be degraded by the action of biochemically active substances such as enzymes. It is also useful in protecting the global environment.

[0013]

Embodiments of the present invention will be described below with reference to the drawings. FIG. 1 shows a first embodiment,
A method for producing a container as a hollow structure will be described. FIG.
Reference numeral 11 in (a) denotes a core, which is a biodegradable polymer, for example, a microbial biopol (trade name of Monsart Co.), which is composed of a copolymer of hydroxybutyrate and valerate or a biosynthetic bionole (Showa Polymer Co., Ltd.) is a polymer composed of aliphatic polyester, succinic acid and polyester of butanediol / ethylene glycol, etc., and decomposed by the action of biochemically active substances such as bacteria and enzymes. The core 11 is formed by blow molding, injection molding, or the like, and has a substantially spherical core body 11a having a narrow opening 11b.

The outer peripheral surface of the core 11 is CFRP or G
The resin layer 12 of FRP is formed. As means for forming the resin layer 12, first, as shown in FIG. 2B, a reinforcing fiber 13 made of carbon fiber or glass fiber is provided on the outer peripheral surface of the core 11. It is wound substantially uniformly (first step). next,
As shown in FIG. 3C, after adding a catalyst to the reinforcing fibers 13, the reinforcing fibers 13 are uncured resin such as unsaturated polyester, epoxy resin, phenol resin or the like.
Is applied (second step).

As a means for adding the uncured resin or the molten resin 14, the uncured resin or the molten resin 14 stored in the tray 15 may be attached to the roller 16 and applied on the reinforcing fiber 13. Although not necessary, the core 11 may be immersed in the molten resin tank together with the core 11, and the uncured resin or the molten resin 14 is impregnated into the reinforcing fibers 13 to form the resin layer 12 having a certain thickness.

In the present embodiment, unsaturated polyester, epoxy resin, or phenol resin is used as the uncured resin or the molten resin 14, and a catalyst is added before coating. Cured when left in place. Before the resin layer 12 is cured, the periphery is wrapped with a film, and the inside of the film is evacuated to vacuum, so that the film adheres to the resin layer 12 and the outer peripheral surface becomes a smooth resin layer 12.

As shown in FIG. 1D, after the resin layer 12 is hardened, biochemically active substances 17 such as bacteria and enzymes, specifically muddy water containing microorganisms, are passed through the opening 11 b of the core 11. The core 11 is decomposed (mainly carbon dioxide and water) when injected into the core 11 and left for several days to several weeks (third step).

After the core 11 has been disassembled, the residue is discharged, as shown in FIG.
The container 18 made of resin reinforced by the above process is completed, and even if the inner peripheral surface of the container 18 has a complicated shape, the residue of the core 11 does not remain, and the core 11 can be easily removed. No unreasonable external force is applied to 18.

FIG. 2 shows a second embodiment, which differs from the first embodiment in the method of forming the resin layer. That is, FIG.
As shown in (a), core 1 made of a biodegradable polymer
After the prepreg 19 is wound around the outer peripheral surface of the prepreg 1 (first step), the core 11 on which the prepreg 19 is wound is housed inside the autoclave 20 as shown in FIG. The resin in the prepreg 19 is cured by heating to form a resin layer 12 reinforced with reinforcing fibers on the outer peripheral surface of the core 11.
Is formed (second step). After the resin layer 12 is hardened, biochemically active substances 17 such as bacteria and enzymes are injected into the core 11 through the opening 11b of the core 11, and the core 11 is decomposed by leaving it for several days to several weeks. (Third
Is the same as in the first embodiment.

Before the resin layer 12 is cured, the periphery is wrapped with a film, and the inside of the film is evacuated to vacuum, whereby the film comes into close contact with the resin layer 12 and the outer peripheral surface becomes a smooth resin layer 12.

FIG. 3 shows a third embodiment, in which the shape of the core is different from the first and second embodiments. That is, FIG.
As shown in (a), a core 2 made of a biodegradable polymer is used.
Reference numeral 1 denotes a plurality of cylindrical or columnar core elements 21a.
, And these core elements 21a are connected by a connector 22 provided at the axis thereof. Therefore, the core elements 21a are connected at predetermined intervals in the axial direction.

Using the core 21, a reinforcing fiber 23 made of carbon fiber or glass fiber is wound substantially uniformly around the outer peripheral surface of the core 21 (first step). In this case, a prepreg may be wound as shown in the second embodiment. Next, as shown in FIG. 2B, after adding a catalyst to the reinforcing fibers 23, the core 21 wound with the reinforcing fibers 23 is formed into a cylindrical shape of a forming die 26 including an upper die 24 and a lower die 25. Is set inside the cavity 27.

In this state, when an uncured resin such as unsaturated polyester, epoxy resin, phenol resin or the like or a molten resin 28 is injected under pressure from the resin injection port 26a of the mold 26, the uncured resin or the molten resin 28
A resin layer 29 filled in the gap between the core 7 and the core 21 and between the cores 21 and having the reinforcing fibers 23 embedded therein is formed (second step).

After the resin layer 29 is cured at room temperature or by heating, the core 21 having the resin layer 29 is taken out of the mold 26. In this case, the core elements 21a constituting the core 21.
Since the biochemically active substance 17 such as bacteria and enzymes is injected into the core 11 at one end, the biochemically active substance 17 is
1a, the connector 22, the core element 21a, and the core 2
1 is decomposed (third step).

Therefore, as shown in FIG. 1C, an independent cylindrical hollow portion 30a is provided at a predetermined interval in the axial direction.
Is obtained. This composite molded product 3
Reference numeral 0 denotes a partition wall 30b formed by the resin layer 29 filled between the core elements 21a.
Ob serves as a bamboo node, resulting in a composite molded article 30 having excellent strength.

FIG. 4 shows a fourth embodiment, in which a wing of an aircraft as a hollow structure is manufactured by an RTM (resin transfer molding) method. FIG.
As shown in (a), grooves 32 are provided in the vertical and horizontal directions for forming ribs by machining on a top surface and a bottom surface of a core 31 made of a biodegradable polymer shaped like an aircraft wing.

Using the core 31, a reinforcing fiber 33 made of carbon fiber or glass fiber is wound substantially uniformly on the outer peripheral surface of the core 31 (first step). In this case, a prepreg may be wound as shown in the second embodiment. Next, as shown in FIG. 3B, after adding a catalyst to the reinforcing fiber 33, the core 31 wound with the reinforcing fiber 33 is formed into a wing shape of a forming die 36 composed of an upper die 34 and a lower die 35. It is set inside the cavity 37.

In this state, when an uncured resin such as unsaturated polyester, epoxy resin, phenol resin or the like or a molten resin 38 is injected under pressure from the resin injection port 36a of the molding die 36, the uncured resin or the molten resin 38 is filled with the cavity 3
The gap between the core 7 and the core 31 and the groove 32 are filled to form the resin layer 39 in which the reinforcing fibers 33 are embedded (second step).

After the resin layer 39 is cured by heating at room temperature or normal temperature, the core 31 having the resin layer 39 is taken out of the molding die 36. In this case, both ends of the core 31 in the longitudinal direction are
6 are in contact with the end faces of the core 31, so that both ends of the core 31
It is exposed from 9. Accordingly, when the biochemically active substance 17 such as bacteria and enzymes is injected into the core 31 (third step), the biochemically active substance 17 is decomposed by the core 31 and the resin layer 39 in which the reinforcing fibers 33 are embedded is embedded. Remains.

Therefore, as shown in FIG. 3C, the wing-shaped composite molded product 40 having a hollow and a rib 40a therein.
Is obtained. In this embodiment, both ends of the core 31 in the longitudinal direction are in contact with the end surface of the molding die 36 so that the resin layer 3
Although the core 31 is exposed from 9, the hollow resin layer 39 is closed at both ends by separating both ends of the core 31 in the longitudinal direction from the end surface of the molding die 36. In this case, a hole is made in a part of the resin layer 39, and the biochemically active substance 17 such as bacteria and enzymes is injected through the hole.

In the above embodiment, the method of manufacturing a composite material container, a composite molded product having an independent cylindrical hollow portion, and a composite molded product of an aircraft wing has been described. However, the present invention is not limited to this, and can be applied to the production of ducts, pots, art objects, and the like.

The biodegradable polymer is not limited to the above embodiment, but may be any of various compositions belonging to a microorganism system, a chemical synthesis system, a natural product utilization system, or a blend system.

[0033]

As described above, according to the present invention, even if the hollow structure has a complicated shape, the core can be easily removed after molding, and the productivity can be improved. In addition, when the core is removed, the hollow structure is not subjected to an excessive external force, and deformation and breakage can be prevented. Further, since no solvent or the like is used, it is also beneficial for global environmental protection.

[Brief description of the drawings]

FIG. 1 is an explanatory view showing a method for manufacturing a hollow structure according to a first embodiment of the present invention.

FIG. 2 is an explanatory view showing a method for manufacturing a hollow structure according to a second embodiment of the present invention.

FIG. 3 is an explanatory view showing a method for manufacturing a hollow structure according to a third embodiment of the present invention.

FIG. 4 is an explanatory view showing a method for manufacturing a hollow structure according to a fourth embodiment of the present invention.

FIG. 5 is an explanatory view showing a conventional method for manufacturing a hollow structure.

FIG. 6 is a perspective view of a hollow structure.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 11 ... Core 12 ... Resin layer 13 ... Reinforcement fiber 14 ... Uncured resin or molten resin 17 ... Biochemically active substance

Claims (3)

[Claims] 1. A first step of winding a reinforcing fiber around an outer peripheral surface of a core made of a biodegradable polymer, and applying an uncured resin or a molten resin to the reinforcing fiber and curing the applied fiber. A second step of forming a resin layer reinforced with reinforcing fibers on the outer peripheral surface, and a third step of introducing a biochemically active substance into a core made of the biodegradable polymer to decompose the core. A method for producing a hollow structure, which is characterized by the following. 2. A first step of winding and laminating a prepreg on the outer peripheral surface of a core made of a biodegradable polymer, and heating the core wound with the prepreg to cure the resin in the prepreg. A second step of forming a resin layer reinforced with reinforcing fibers on the outer peripheral surface of the core, and a third step of introducing a biochemically active substance into the core made of the biodegradable polymer to decompose the core. A method for producing a hollow structure, comprising: 3. A first step of winding a reinforcing fiber around an outer peripheral surface of a core made of a biodegradable polymer; and storing the core wound with the reinforcing fiber in a molding die. A second step of injecting a cured resin or a molten resin to form a resin layer reinforced with reinforcing fibers on the outer peripheral surface of the core, and taking out the resin layer reinforced with reinforcing fibers from the mold to biodegrade A third step of introducing a biochemically active substance into a core made of a conductive polymer and decomposing the same, and a method for producing a hollow structure.