JPH11262927A - Reactive polymerization molding method and tubular molded object - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a tubular molded object having excellent characteristics such as high rigidity, impact resistance or the like and capable of realizing connection excellent in the hermetic sealability and water stopping properties of a connection part. SOLUTION: Resin members 7, 7 are arranged to an almost cylindrical mold 2 along the inner surfaces of both end parts of the mold 2 in the axial direction of the mold 2 and a reactive raw soln. is charged in the mold 2 and subjected to reactive polymn. by applying centrifugal force to the reactive raw soln. by rotating the mold 2 to produce a tubular molded object having a resin member 7 integrally. The end surfaces of a plurality of the tubular molded objects thus produced are mutually abutted to be heated and the opposed resin members 7 are mutually heated and fused to mutually connect tubes.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a reactive polymerization molding method and a tubular molded article, and more particularly, to a method in which a reaction stock solution is put into a mold, and the mold is rotated to apply a centrifugal force to the reaction stock solution. The present invention relates to a reactive polymerization molding method in which a reaction polymerization is carried out under a condition, and a tubular molded article produced by the method.

[0002]

2. Description of the Related Art In the present specification, the term "reactive polymerization molding method" broadly means a method in which a reaction stock solution is reacted and polymerized in a mold.
As an embodiment, there is a reaction injection molding (RIM) method.

The RIM method is a manufacturing method in which two or more undiluted reaction solutions are mixed in a mixing chamber, fed into a cavity of a mold apparatus, and subjected to injection molding while reacting in the mold apparatus. This RIM method is suitably used for forming a polymer (molded article) from a norbornene-based monomer. Since the RIM molded body has the characteristics of excellent impact resistance, low molding pressure, and easy molding, it has been studied for use in various technical fields.

[0004] However, forming a molded article having a hollow interior such as a tube by the conventional reaction injection molding requires a nesting mold or the like in a portion corresponding to the hollow portion, which is extremely difficult. It was difficult. In addition, when a nesting mold or the like is placed in a portion corresponding to the hollow portion, the reaction injection molded resin that comes into contact with the nesting mold is cooled during molding, and there is a possibility that poor curing may occur.

Further, when the molded article is used as a tube or the like, it is required that the inner surface of the tube be smooth because the fluid flows through the tube, so that the occurrence of defects on the inner surface of the tube is minimized. There is a need.

Incidentally, in the case of a tube-shaped molded article formed by a usual extrusion molding method using polyethylene or the like, the rigidity of the molded article is low and the molding requires a long time, so that the productivity is poor.

[0007] Further, the reaction stock solution is mixed and put into a rotating mold, and the mold is rotated to apply a centrifugal force to the reaction stock solution to cause the reaction stock solution to react and polymerize inside the mold. Accordingly, a technique for manufacturing a tubular molded body has been proposed (see US Pat. No. 4,808,364). In the centrifugal molding as disclosed in this publication, since molding is performed while applying a centrifugal force to the reaction solution, it is expected that bubbles contained in the solution will be reduced.

[0008]

In the case of relatively large-diameter pipes buried underground, such as pipes for water supply and sewage and other pipes, it is necessary to sequentially connect and connect the tubular moldings to each other. In order to prevent leakage of the fluid flowing through the inside, the connecting portions need to be excellent in sealing performance and waterproofness. In addition, since the connection work is performed on site, it is also required that the connection work be easy.

However, since the molded article obtained by the above-mentioned reactive polymerization molding method is a thermosetting resin and the like, the end portions thereof are joined by heat fusion, which are generally used for connecting a polyethylene pipe or the like. In many cases, it is difficult to make a connection by butt joining. In addition, it is often difficult to integrate them by bonding using a normal adhesive. Therefore, it is necessary to use a method using a flange pipe joint. However, in this method, since the flange portion becomes an obstacle, the pipe work by the propulsion method of burying the tube by axially propelling the tube in soil such as reki or sand. Not suitable for

[0010] Japanese Patent Application Laid-Open No. 3-69357 discloses that
Using a polyethylene tube having adhesiveness to the molded body as a mold, a reactive polymerization reaction is performed while rotating the polyethylene tube around the axis, and a reactive polymer molded body layer is formed on the inner surface of the polyethylene tube. A technique for manufacturing a molded article is disclosed.

However, this technique is an excellent technique in that the polyethylene pipe has a low rigidity and is reinforced by a reactive polymer molded article layer. However, since the polyethylene pipe is used as a mold, the mold is not used. Since the thickness of the polyethylene tube must be sufficiently resistant to centrifugal force during molding, it cannot be reduced inevitably, and the entire outer periphery of the tube has a certain thickness of polyethylene. Since it is a layer, there is a drawback that there are many restrictions on forming a tube-shaped molded product that sufficiently reflects the excellent properties of the reactive polymer molded product, such as high rigidity and impact resistance.

The present invention has been made in view of such circumstances, has excellent characteristics such as high rigidity and impact resistance, and
It is an object of the present invention to provide a tubular molded body capable of realizing a joint having excellent sealing properties and waterproofness of a connecting portion, and a method for producing the same. Another object of the present invention is to provide a tubular molded body suitable for plumbing work by a propulsion method.

[0013]

According to the reactive polymerization molding method of the present invention for achieving the above object, a resin member is arranged along an inner surface of at least one axial end of a substantially cylindrical mold. A reaction solution is put into the mold, and the reaction polymerization is performed while rotating the mold to apply a centrifugal force to the reaction solution. Note that the cylindrical shape is not limited to a cylindrical shape, and includes a cylindrical shape having a rectangular or other cross-sectional shape.

According to this method, it is possible to obtain a tubular reactive polymer molded article having a resin member integrally at at least one end in the axial direction. As this resin member,
Depending on the intended use of the tube-shaped molded article, for example, a material having a heat-fusing property, a material having good adhesiveness with an adhesive, a material having a water swelling property, or a material having a combination of these properties is adopted. can do.

For example, if a resin member having a heat-fusing property is used, the resin members of the obtained tubular molded body and other similarly molded tubular molded bodies are brought into contact with each other, and heated to the opposite resin. By fusing the members together, the tubular molded body can be easily and integrally connected to another tubular molded body. In addition, by appropriately selecting the material and properties of the resin member in relation to the adhesive used for the connection in consideration of the adhesiveness, it is possible to realize a connection excellent in the sealing property of the connection portion, for example, inexpensive general By selecting a commonly used adhesive and selecting a resin member in relation to this, cost reduction can be achieved at the same time.

When a resin member having water swelling properties is used, it is possible to improve the water stopping property of the connecting portion when a plurality of the obtained tubular moldings are connected to each other.

Although the resin member used in the present invention is not particularly limited, polyethylene (PE), polypropylene, polybutylene, polystyrene, ethylene / vinyl acetate copolymer (EVA), etc. are used as the resin member having heat-fusibility. When connection by an adhesive is considered, polyvinyl chloride (PVC), polyacetal, acrylic resin, nylon, polyethylene terephthalate, or the like can be used. When a reaction solution containing a norbornene-based monomer described below is used as the reaction solution, a polyethylene or ethylene-vinyl chloride copolymer (PVC) having good bonding properties with a molded article formed by using the reaction solution is used. In which 8% by weight or more of PE is contained).

Examples of the water-swellable resin member include sodium polyacrylate, potassium polyacrylate, starch-polyacrylate graft copolymer, acrylic acid-vinyl alcohol copolymer, modified polyethylene oxide, and polyvinyl oxide. Alcohol-maleic acid ester copolymer, 1 mole of isobutylene and maleic anhydride:
One mole of alternating copolymer, polyacrylate fiber, sodium carboxymethylcellulose, or the like can be used. When a reaction stock solution containing a norbornene-based monomer described below is used as the reaction stock solution, an acrylic acid-vinyl alcohol copolymer, an alternating copolymer of isobutylene and maleic anhydride at a mole of 1 mole: 1 mole is particularly preferable. .

The shape of the resin member is not particularly limited, but its cross section (cross section cut along the plane including the central axis of the mold) is circular, elliptical, rectangular, trapezoidal, or any other shape, and the whole is circular. An endless member having a ring shape, a rectangular ring shape, or another shape having a shape along the inner surface of the mold can be employed. This resin member can be disposed at one end and / or the other end of the axial ends of the mold. Further, if necessary, it can be arranged at an intermediate portion in the axial direction of the mold. Further, the resin member may be in the form of a film or a sheet.

In the method of the present invention, when forming a tube-shaped molded body, there is no need to insert a nesting mold or the like, as compared with the conventional RIM molding method. There is no danger of the resin being cooled upon contact with the nesting mold and causing poor curing of the resin. Also,
Since the reaction polymerization is performed while applying the centrifugal force, bubbles in the reaction solution are removed by the centrifugal force, so that a molded article having few voids is obtained, and a tubular molded article having good mechanical strength and durability of the molded article is manufactured. can do.

In the present invention, the inside of the mold can be subjected to the reaction polymerization under a positive pressure state, whereby a molded article with less voids can be obtained. The pressure in this case may be at least atmospheric pressure. This positive pressure state can be achieved by supplying dried air into the mold, but other gases can also be used, and it is particularly desirable to use an inert gas such as nitrogen gas. This is to prevent the alkylaluminum catalyst from reacting with oxygen and lowering the polymerization activity.

In the present invention, the lower limit of the acceleration based on the centrifugal force is not particularly limited, but is preferably 0.5 G or more, more preferably 1 G or more, and particularly preferably 1.2 G or more.
Acceleration of G or more is good. If the acceleration is too low, the undiluted solution tends not to adhere uniformly to the inner peripheral surface of the mold, and a molded article having a uniform thickness tends to be hardly obtained.

In the present invention, the upper limit of the acceleration is not particularly limited, but when obtaining a large molded product, the acceleration is preferably 5 G or less, more preferably 4 G or less.

A filler can be mixed into the reaction stock solution. In this case, before the centrifugal force of a predetermined acceleration is obtained, the mold is rotated with a centrifugal force such that the acceleration becomes 1 G or less. (Preparation rotation) is preferable. This is for sufficiently mixing the filler and the reaction solution before molding by the polymerization reaction. From such a viewpoint, the time required for the preparation rotation is
It is preferable that the time is up to the pot life (pot life).

In the present invention, the undiluted reaction solution is placed in a mold in advance, and then the centrifugal force is applied by rotating the mold, or the undiluted reaction solution is rotated after the rotation of the mold. Can be injected.

Reaction stock solution The composition of the reaction stock solution is not particularly limited, but examples thereof include urethane, urea, nylon, epoxy, unsaturated polyester, phenol and norbornene systems, with norbornene systems being particularly preferred. The temperature of the reaction solution before it is put into the mold is preferably 20 to 80 ° C., and the viscosity of the reaction solution at, for example, 30 ° C. is preferably 50 to 1500 cps, more preferably 100 to 1 cps.
It is about 200 cps.

If the viscosity of the reaction solution is too low, the reaction solution tends to stay at the bottom without centrifugal force acting on the solution.
If the viscosity is too high, free-form molding using acceleration tends to be difficult.

As described above, a filler can be mixed in the reaction solution. The filler is not particularly limited, but may also serve as a reinforcing agent or a flame retardant. For example, as a fibrous material, aramid fiber,
Organic fiber such as carbon fiber, ultra high molecular weight polyethylene fiber, polypropylene fiber, cotton, acrylic fiber, vinylon fiber and inorganic fiber such as glass fiber, metal fiber, aluminum coated glass fiber, boron fiber, silicon carbide fiber, alumina fiber, etc. Can be mentioned. Granular or block fillers include silica sand,
Examples include milled glass, carbon black, talc, clay (aluminum silicate), diatomaceous earth, calcium carbonate, aluminum hydroxide, mica, potassium titanate, calcium sulfate, and the like. The filler may be put in a mold before putting the undiluted solution.

The reaction stock solution is mixed with various additives such as an antioxidant, a pigment, a colorant, a sliding agent, an elastomer, a dicyclopentadiene-based thermopolymerized resin and a hydrogenated product thereof together with the filler. Is also good. The properties of the resulting polymer can be modified by adding additives.

As the antioxidant, there are various antioxidants for plastics and rubbers such as phenol type, phosphorus type and amine type. Examples of the elastomer include natural rubber, polybutadiene, polyisoprene, styrene-butadiene copolymer (SBR), styrene-butadiene-styrene block copolymer (SBS), styrene-isoprene-styrene block copolymer (SIS), and ethylene- Examples include propylene-diene terpolymer (EPDM), ethylene vinyl acetate copolymer (EVA) and hydrides thereof. The additive is usually mixed in advance with one or both of the reaction solutions.

[0031] In the mold present invention, a resin member disposed on the inner surface of the mold, was placed the reaction stock solution in the interior of the mold, such that it can apply a centrifugal force to the reaction stock solution inside the mold It has a structure.
For example, a mold is rotatable around one axis or multiple axes. By rotating the mold, an acceleration due to centrifugal force acts on the reaction solution inside the mold.

When the inside of the mold is made to have a positive pressure, it is necessary that the mold has a sealable structure and that a gas supply port for supplying gas from a gas supply device or the like be provided. Pressurization in the mold is performed by supplying gas at a constant pressure from gas supply means. In addition, the pressure in the mold can be controlled to be constant by the gas supply device, or a gas of a predetermined pressure is supplied by the gas supply device, and when the pressure in the mold becomes equal to or higher than a certain pressure, the pressure is increased by the relief valve. And the inside of the mold may be maintained at a constant pressure.

The temperature of the mold is preferably from 10 to 150
° C, more preferably 20 to 120 ° C, still more preferably 30 to 100 ° C. Temperature control of the mold is not necessarily required in the present invention, but when performing temperature control while rotating the mold, as a heating means,
It is preferable to use a lamp, warm air, or the like.

Before injecting the unreacted solution into the mold,
Warm air is circulated inside the mold, and after at least the inside of the mold cavity is heated to a predetermined temperature, the circulation of the warm air is stopped, and the reaction stock solution is poured into the cavity of the mold apparatus to perform molding. Is also good.

The material of the mold used in the present invention is as follows.
Although not particularly limited, a material having good adhesiveness to the mold and a material that is non-adhesive to the molded body is preferable in order to obtain a molded body having a smooth outer peripheral surface, for example, cast iron,
Metals such as iron, stainless steel, aluminum and nickel electroformed are preferred. However, as long as the material is non-adhesive to the molded body, a synthetic resin or another material may be used. Reactive polymerization molding can be performed at relatively low pressure, so it is not always necessary to use a high-rigidity mold. It is necessary to design the pressure resistance of the mold.

When the mold is made of a synthetic resin, the synthetic resin may be a fiber-reinforced plastic (FRP), phenol, polyester, P
It is preferable to use a polar resin such as VC because the resin is not integrated with the reactive polymer molded article, and the mold apparatus can be removed and used repeatedly for each reactive polymer molding.

As the mold, a split mold that can be divided is preferable because it can be formed into a free shape, but a cylindrical mold that is not divided may be used. In the case of a cylindrical mold, it is necessary to adopt a configuration that does not hinder the work of disposing (mounting) the resin member in the mold, and it is necessary to pull out the obtained molded body. In order to improve the moldability, it is also preferable to apply a wax, a lubricant, or the like in advance along the inner peripheral surface of the mold before injecting the stock solution. When the molded body is pulled out, the temperature of the molded body is lower than the glass transition temperature (Tg) of the molded body, preferably (Tg-50) ° C.
It is preferable to start drawing the molded body after the temperature reaches the following. That way, the shape of the molded body will not collapse,
This is because workability is good.

[0038]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be described below based on embodiments shown in the drawings.

FIGS. 1A and 1B are schematic perspective views of a mold used in a reactive polymerization molding method according to one embodiment of the present invention.
FIG. 2C is a schematic sectional view of the mold, FIG. 2 is a side view of a drive unit for rotating the mold, FIG. 3 is a plan view of the drive unit, and FIG. Figure, (B) is (A)
(C) is a cross-sectional view taken along the line cc of (A), FIG. 5 is an enlarged cross-sectional view of a connecting portion of the piping tube, and FIG. It is an outline sectional view of a metallic mold used for a reactive polymerization molding method concerning an embodiment.

First Embodiment In this embodiment, a method for producing a pipe tube by reacting and polymerizing a reaction solution containing a norbornene-based monomer will be described. In this embodiment, a mold 2 shown in FIGS. 1A, 1B, and 1C is used to apply a centrifugal force to the reaction stock solution.

The mold 2 is attached to the outer periphery of both ends of the mold 4 from the axial direction in a state in which the mold 4 can be divided into two along the dividing surface 3 in the vertical direction. And a pair of rolling rings 8. The split mold 4 is made of, for example, an aluminum casting, and the rolling ring 8 is made of cast iron.

It is preferable that a sealing material is mounted on the split surface 3 of the split mold 4. By installing the sealant, it is possible to prevent inconvenience such as leakage of the undiluted reaction solution from the split surface 3. Suitable sealing materials used in the present embodiment include:
There is no particular limitation, and a silicone rubber sealing material or the like can be used.

An inner peripheral surface is formed inside the split mold 4 combined with the split surface 3, and a reaction stock solution having a predetermined viscosity is pressed against the inner peripheral surface by centrifugal force having a predetermined acceleration. It is supposed to be. End plates 6 and 6 are formed at both ends in the axial direction of the split mold 4 so that the through holes 5 are formed.
A nozzle for supplying the undiluted reaction solution is inserted from the through hole 5, so that the undiluted reaction solution can be supplied into the mold 2.

As shown in FIGS. 2 and 3, a pair of flanged drive rollers 12 is engaged with one of the rolling rings 8 of the mold 2, and the other of the rolling rings 8 has no pair of flanges. Drive rollers 14 are engaged with each other. These drive rollers 12 and 14 are connected to a transmission 16 and a constant torque inverter motor 18 and all rotate at substantially the same rotational speed. When these drive rollers 12 and 14 are all rotated at substantially the same rotational speed, the rolling ring 8 engaged with them is also rotated around its axis, and the mold 2 composed of the split dies 4 and 4 is also rotated. At the same time, it rotates around the axis. The driving rollers 12, 14,
The transmission 16 and the motor 18 are mounted on a base 20. The reason why the one driving roller 12 in the axial direction is provided with a flange is that the flange restricts the axial movement of the rolling ring 8, thereby restricting the axial movement of the mold 2. The drive rollers 12, 14 in both axial directions may be provided with flanges, but only one of them can sufficiently limit the axial movement of the mold 2.

As a preparation before performing the reactive polymerization molding in this embodiment, a plurality of resin members having a shape indicated by reference numeral 7 in FIG. 1 (C) are prepared. The resin member 7 is, for example, a member formed by using a resin material having a heat-fusing property (thermoplasticity) and a resin material having good adhesiveness and bonding property with an adhesive, and is not particularly limited. In the case of using a solution containing a norbornene-based monomer as the undiluted reaction solution, polyethylene (PE) or ethylene vinyl chloride can be used.

In this embodiment, the shape of the resin member 7 is as follows.
Each of the dies 4 and 4 has a cylindrical shape having an outer peripheral surface along the inner peripheral surface, and a cut surface cut along a plane including the central axis thereof is substantially rectangular. However, the resin member 7 is not limited to such a shape, and the cut surface may be a trapezoid, a circle, an ellipse, or any other shape, and a cut surface cut along a plane perpendicular to the center axis thereof. May be rectangular or other shapes in consideration of the relationship with the shape of the inner peripheral surface of the mold as well as a circle. The resin member 7 may be in the form of a film or a sheet.

Next, a method for forming a tube by the reactive polymerization molding method using the mold 2 will be described.

First, as shown in FIGS. 1 (B) and 1 (C), resin members 7, 7 are respectively attached to both ends of the split dies 4, 4 along the inner peripheral surfaces of the split dies 4, 4 and the inner surface of the end plate 6. After being arranged, the split dies 4 and 4 are combined. Then, as shown in FIG. 1 (A), rolling rings 8 and 8 are attached to both ends of the combined split dies 4 and 4, Assemble 2. Next, the mold 2 is placed on the drive rollers 12 and 14 shown in FIGS.
Place it rotatably.

Thereafter, reactive polymerization molding is performed. The reactive polymerization molding performed in the present embodiment is a molding using a norbornene-based monomer. Specific examples of the norbornene-based monomer to be used include bicyclics such as norbornene and norbornadiene; dicyclopentadiene (cyclopentadiene dimer). ), Tricyclics such as dihydrodicyclopentadiene; tetracyclics such as tetracyclododecene; pentacyclics such as cyclopentadiene trimers; heptacyclics such as cyclopentadiene tetramers; methyl, ethyl, Substitutes such as alkyl such as propyl and butyl, alkenyl such as vinyl, alkylidene such as ethylidene and the like such as aryl such as phenyl, tolyl and naphthyl; and further substituted compounds having a polar group such as an ether group and a halogen atom. You. These monomers may be used in combination of one or more kinds. Tricyclic, tetracyclic, or pentacyclic monomers are preferred from the viewpoint of easy availability, excellent reactivity, and excellent heat resistance of the obtained resin molded product.

The ring-opening polymer to be formed is preferably of a thermosetting type. For this purpose, among the above norbornene-based monomers, it has two or more reactive double bonds such as cyclopentadiene trimer. Those containing at least a crosslinkable monomer are used. The proportion of the crosslinkable monomer in all the norbornene monomers is preferably from 2 to 30% by weight.

It should be noted that, within a range not to impair the object of the present invention,
Monocyclic cycloolefins such as cyclobutene, cyclopentene, cyclopentadiene, cyclooctene and cyclododecene, which can be ring-opening copolymerized with norbornene monomers,
It may be used as a comonomer.

The metathesis catalyst which can be used in molding using a norbornene-based monomer is a norbornene-based catalyst such as tungsten hexachloride, or an organic ammonium molybdate such as tridodecyl ammonium molybdate or tri (tridecyl) ammonium molybdate. There is no particular limitation as long as it is a known metathesis catalyst as a catalyst for bulk polymerization of monomers, but an organic ammonium molybdate is preferred.

As the activator (co-catalyst), JP-A-58-1983
127728, JP-A-4-226124,
JP-A-58-129003, JP-A-4-1452
There is no particular limitation as long as it is a known activator as disclosed in Japanese Patent No. 47, for example, alkyl aluminum halides such as ethyl aluminum dichloride and diethyl aluminum chloride, organic aluminum compounds such as alkoxyalkyl aluminum halides, and organic tin. And the like.

As preparation for molding, a molding material mainly composed of a norbornene-based monomer, a metathesis catalyst and an activator was mixed with a liquid B composed of a norbornene-based monomer and a metathesis catalyst, and the aforementioned norbornene-based monomer and activator. The liquid is divided into two stable liquids and the liquid A, each of which is placed in a separate tank.

When a filler is added, a filler such as silica sand having an average particle size of about 0.1 to 2.0 mm is put in the mold in advance. The filling ratio of the filler is not particularly limited, but is preferably about 10 to 100% by weight when the total weight of the reaction stock solution put in the mold is 100% by weight.

To start molding, control the mixer,
The solution A and the solution B from the tank are mixed, and the mixed solution is used as a reaction stock solution by using a nozzle or the like to form the through-hole 5 of the mold 2.
From the mold 2. The viscosity of the reaction solution supplied into the mold 2 is 50 cps to 15 at 30 ° C.
00 cps.

In the present embodiment, the mold 2 does not necessarily need to be heated, but may be heated using a heating medium or hot air from the viewpoint of facilitating the polymerization reaction.

The rotation speed of the mold 2 is 1 G or more and 5
G or less, and it depends on the diameter of the inner peripheral surface of the mold 2.
When the thickness is set to about 600 mm, the rotational speed of the mold 2 around the axis is preferably about 80 to 150 rpm. Mold 2
The initial start-up (preparation rotation) time required to rotate at a constant rotation speed around the axis is about several seconds to 30 seconds. During this preparation rotation time, the reaction stock solution and the filler are
An acceleration of about 1 G or less is applied, and the unreacted solution and the filler are uniformly mixed. Then, increase the rotation speed of the mold,
At a constant rotation speed, an acceleration of about 1 G to 5 G is applied to the reaction solution and the filler in the mold. After the mold 2 is rotated around the axis thereof at a constant rotation speed, a nozzle may be inserted through the through-hole 5 to supply the reaction solution.

By rotating the mold 2 around the axis thereof at a constant rotational speed, the unreacted solution supplied into the mold 2 is centrifuged to cause the inner peripheral surface of the mold 2 and the resin member 7 to move. Will be stuck to the inner peripheral surface of the tube. Also, when a filler is added, the filler is dispersed in the reaction stock solution to those having a larger specific gravity than the reaction stock solution to the outside and those having a smaller specific gravity to the inside. The state, for example,
By holding for 10 minutes, the reaction in the reaction stock solution proceeds, and bulk polymerization is performed.

Then, after the rotation of the mold 2 is stopped and the mold 2 is cooled, the rolling ring 8 is removed from the state shown in FIG. 1A to the state shown in FIG. , Split mold 4,4
By opening, a tubular molded body 10 as shown in FIG. 4A can be obtained. This tubular molded body 10
Is mainly composed of a reactive polymer molded product of a norbornene-based monomer, and as shown in FIGS. 4 (A) and 4 (B), has resin members 7 integrally at the outer peripheral portions at both ends. Although the thickness of the obtained molded body 10 is not particularly limited, in the present embodiment, it is about 10 to 30 mm, and the thickness of the resin member 7 is about 2 to 10 mm.

In the method according to the present embodiment, by applying a centrifugal force to the reaction stock solution, bubbles are separated from the reaction stock solution by the centrifugal force during molding, and voids are eliminated in the obtained molded product.

The inner peripheral surface of the tubular molded body 10 shown in FIG. 4A obtained by the method of this embodiment is a surface obtained by centrifugal force without touching anything in the molding process. Therefore, there is no inconvenience such as poor curing of the reaction stock solution during molding, and the inner peripheral surface is smooth. The obtained tubular molded body is used, for example, as a fluid pipe or the like, and a fluid flows through the pipe. Therefore, it is convenient to use the pipe as a pipe having a smooth inner peripheral surface.

The tubular molded article obtained by the method according to the present embodiment is a polymer obtained by utilizing a bulk polymerization reaction of a norbornene-based monomer. Excellent mechanical properties. Further, according to this method, even a relatively large-diameter tubular molded body can be molded relatively easily.

Further, in the present embodiment, the split dies 4 are used, the rolling rings 8 are mounted on the outer periphery thereof, and the die 2 is attached to the shaft center by using the rolling rings 8. Since it is rotated around, it is possible to realize both the free-form molding of the molded body by using the split mold and the rotation using the ring with little rotational fluctuation. In addition, if rotational blur occurs, the rotational blur can be suppressed by shaving the outer circumference of the rings 8 during rotation. Further, replacement of the rings 8, 8 is also easy.

The use of the tube-shaped molded article obtained by the present embodiment is not particularly limited. Particularly, as a pipe having a large diameter (400 mm or more, 1000 to 2000 mm), a sewage pipe, a water pipe for an agricultural road, a pipe for a dam, etc. It can be suitably used as a water pipe, a water distribution pipe for building land development, and other pipes. In addition, since the resin members 7 are integrally disposed on the outer periphery of both ends of the tubular molded body, the occurrence of burrs and the like on the end surface of the tube is small, and the contact surface when connecting with another tube is reduced. Good adhesion.

In the case where the tube-like formed body thus manufactured is used as a pipe, as shown in FIG. 5, a plurality of tube-shaped formed bodies (piping tubes) 10 manufactured by the above-described method are sequentially arranged. It will be connected and connected. The connection work is performed on the piping tubes 10 and 10 to be connected.
Of the resin members 7, 7
Against each other.

When a heat-fusing material such as polyethylene is used as the resin member 7, the tubes 10 are integrally connected by heating to fuse the resin members 7 together. . Further, the EF joint (pipe) 11 can be positioned outside the resin members 7, 7 and energized to be integrally fused. Furthermore, the large-diameter pipe joint currently used can be diverted as it is. In addition, EF (elec
A tro fusion joint (electro-fusion joint) is a pipe made of polyethylene or polybutylene containing a nichrome wire, which is melted by the heat generated by energizing the nichrome wire, and heat-fused with the pipe arranged inside. It is intended to be worn.

When a material such as polyvinyl chloride is used as the resin member 7, the piping tubes 10, 10
Can be connected by applying an adhesive to the end surfaces of the tubes and butting them together, or by applying an adhesive to the outer surfaces of the tubes 10 and 10 and positioning a PVC collar (11).

Since the tubular molded body 10 obtained by the reactive polymerization molding method of the present embodiment has the resin members 7 having the heat-sealing property at both ends thereof, it was molded in the same manner as the other. By abutting the resin members 7 of the tubular molded body 10 to each other and performing heat fusion or the like, a plurality of tubular molded bodies can be easily integrated.

As described above, the tubular molded body 10 obtained by the method of the present embodiment can be easily connected by heat fusion or an adhesive, and can have mechanical properties such as impact resistance and durability. And a molded body having excellent inner surface smoothness and excellent sealing performance of a connection portion when used as a pipe.
In addition, since there is no need to use a flange pipe joint and the flange portion (projection) does not become an obstacle, the pipe work by the propulsion method of burying by propelling the tube in the axial direction in the soil such as rubble, sand, etc. It is suitable for.

Second Embodiment In this embodiment, a mold 22 and a resin member 2 shown in FIG.
Except for using 7, a reaction solution containing a norbornene-based monomer is reacted and polymerized in the same manner as in the first embodiment.

In this embodiment, a mold 22 shown in FIG. 6 is used. The mold 22 includes a split mold 24 that can be divided into two along the split surface 23 in the vertical direction, and a pair of rolls attached to the outer periphery of both ends in the axial direction in a state where the split mold 24 is combined. And a moving ring 28. The split mold 24 is made of, for example, an aluminum casting or the like.
8 is made of cast iron or the like.

It is preferable that a sealing material is mounted on the split surface 23 of the split mold 24. By installing the sealing material,
Inconveniences such as leakage of the undiluted reaction solution from the split surface 23 can be prevented. The sealing material suitable for use in the present embodiment is not particularly limited, and a silicone rubber sealing material or the like can be used.

An inner peripheral surface 24a is formed inside the split mold 24 combined with the split surface 23, and one end in the axial direction (the left end in the figure) of the inner peripheral surface is narrowed like a step. Formed,
In addition, an inner peripheral surface (small diameter portion) 24b having a reverse tapered shape is formed so that the inner diameter becomes smaller toward the end. A reaction stock solution having a predetermined viscosity is pressed against the inner peripheral surfaces 24a and 24b by a centrifugal force having a predetermined acceleration. A cutout 24c for arranging (mounting) a resin member 27 described later is formed at a boundary between the inner peripheral surfaces 24a and 24b of the dies 24, 24.

A through hole 25 is formed at one axial end of the split mold 24.
The end plate 26a is integrally formed so that a is formed. An end plate 26b having a through-hole 25b is attached to the other end in the axial direction (the right end in the figure) of the split 24. The end plate 26b is formed in a tapered shape so that its outer periphery becomes thinner toward the tip, and a through hole 29b is formed in the center.
A substantially cylindrical nesting mold 29 having the shape shown in FIG. The nesting mold 29 has a shape roughly corresponding to the small diameter portion 24a. The nesting mold 29 is made of a material having elasticity, such as rubber, soft PVC, and EVA, although not particularly limited. From the through holes 25a, 25b, 29b, nozzles for supplying a reaction solution are inserted,
A reaction solution can be supplied into the mold 22.

As a preparation for performing the reactive polymerization molding in this embodiment, a resin member having a shape indicated by reference numeral 27 in FIG. 6 is prepared. The resin member 27 in this embodiment is a resin member having water swelling property, and for example, an acrylic acid-vinyl alcohol copolymer or a 1 mol: 1 mol alternating copolymer of isobutylene and maleic anhydride is suitably used. be able to.

In this embodiment, the shape of the resin member 27 is an annular shape along the notch 24c formed at the boundary between the inner peripheral surfaces 24a and 24b of the mold 22. However, the resin member 27 is not limited to such a shape, and may have a trapezoidal shape, an elliptical shape, or any other shape cut along a plane including the central axis, and a plane orthogonal to the central axis. The cut surface cut by the method described above may be not only a circle but also a rectangle or another shape in consideration of the relationship with the shape of the inner peripheral surface of the mold. The resin member 27 may be in the form of a film or a sheet.

Next, a method of forming a tube by the reactive polymerization molding method using the mold 22 will be described.

First, after the resin member 27 is arranged along the notch 24c of the split dies 24, 24, the split dies 24, 2
4 and then the combined split molds 24, 24
Rolling rings 28, 28 are attached to both ends of the mold, and the mold 22 is assembled. Next, the mold 22 is rotatably mounted on the drive rollers 12 and 14 shown in FIGS.

Thereafter, reactive polymerization molding is performed. Through hole 2
Nozzles are inserted from 5a, 25b, and 29b to supply the undiluted reaction solution, and the mold 22 is rotated at a constant rotational speed around its axis, whereby the undiluted reaction solution supplied to the inside of the mold 22 is centrifuged. The force causes the inner peripheral surfaces 24a and 24b of the mold 22 and the resin member 27 to be attached in a tubular shape.
The reaction in the reaction stock solution proceeds, and bulk polymerization is performed.

Thereafter, the rotation of the mold 22 is stopped, and the mold 2 is rotated.
After cooling 2, the rolling ring 28 is removed, the end plate 26b and the nesting mold 29 are removed, and the split dies 24, 24 are opened, whereby a tubular shaped body 30 can be obtained. According to the method of the present embodiment, it is possible to easily form even the tubular molded body with such a joint.

The tubular molded body 30 is mainly composed of a reactive polymer molded body of a norbornene-based monomer. The tubular molded body 30 has a tapered joint insertion portion 30a at one end thereof and another end thereof. The portion has an integrally inserted reversely tapered joint insertion portion 30b. Further, the tubular forming body 30 integrally has a water-swellable resin member 27 at the base end of the joint insertion portion 30a.

[0098] A joint insertion portion 30a of another tubular shaped body 30 is inserted into the inside of the joint insertion portion 30b so as to be connectable. Plural tubular shaped bodies 3
0, the resin member 27 has a water swelling property in a piped state, so that when a water flow is circulated inside the resin member 27, the resin member 27 expands with moisture and the tubes are connected to each other. The gap between the parts will be closed.

The tubular molded body 30 obtained by the reactive polymerization molding method of the present embodiment integrally has a water-swellable resin member 27, and has a joint insertion portion 30a and a joint inserted portion 30b. Therefore, the connection operation is easy, and the connection with high waterproofness can be realized. In particular, since there is no protrusion like a flange on the outer circumference of the tube,
It is particularly suitable for plumbing work by a propulsion method in which a tube is buried by being propelled in the axial direction in soil such as rubbed sand.

Other Embodiments The present invention is not limited to the above-described embodiments, and can be variously modified within the scope of the present invention. For example, the mold that can be used in the present invention is not limited to the above-described embodiment, and can be variously modified.

Further, in the embodiment described above, the mold is
Although rotated about the axis, it may be rotated about two or more multi-axes.

[0087]

EXAMPLES Hereinafter, the present invention will be described based on more detailed examples, but the present invention is not limited to these examples.

Example 1 A mold 2 shown in FIG. 1A was prepared and set on drive rollers 12 and 14 of a mold rotating device shown in FIGS. The pair of split molds 4 and 4 were made of an aluminum casting, had an outer diameter of 500 mm, an inner diameter of 400 mm, and an axial length of 1200 mm. The inner diameter of the through hole 5 of the end plate 6 formed at both ends of the split dies 4 and 150 was 150 mm.

The split dies 4 and 4 were combined on the split surface 3.
A silicone rubber sealing material was attached to the split surface 3.

Resin members 7 were disposed (mounted) at both ends of the split dies 4 and 4 respectively. As the resin member 7, a polyethylene tube was used. The outer diameter of the resin member 7 is substantially equal to the inner diameter of the molds 4 and 4, the wall thickness is 3 mm, and the axial dimension is 1 mm.
00 mm.

The rolling rings 8, 8 were attached with the split surfaces 3 of the split dies 4, 4 sealed. Rolling ring 8,8
Was made of cast iron, its outer diameter was 700 mm, and its axial thickness was 50 mm.

The rolling rings 8, 8 are connected to the driving rollers 12, 14.
Then, 15 kg of the reaction stock solution was supplied into the mold 2 from the axial through hole 5 of the split mold using a nozzle. The preparation of the reaction stock solution was performed as follows. A mixed monomer composed of 85% by weight of dicyclopentadiene (DCP) and 15% by weight of tricyclopentadiene was used, and a styrene-isoprene-styrene block copolymer (Clayton 1170, Shell Co., Ltd.) was used based on 100 parts by weight of the total amount of the monomers. 5 parts by weight) and 2 parts by weight of Irganox 1010 (manufactured by Ciba-Geigy), which is a phenolic antioxidant, are placed in two containers, and one of them is mixed with diethyl aluminum chloride based on the mixed monomer. (DEAC) at a concentration of 40 mmol (millimolar equivalent to 1 mol of the mixed monomer is hereinafter referred to as "mmol concentration").
), N-propanol was added to a concentration of 44 mmol, and silicon tetrachloride was added to a concentration of 20 mmol (A
liquid). On the other hand, tri (tridecyl) ammonium molybdate was added to the mixed monomer at a concentration of 10 mmol (solution B).

The liquid A and the liquid B are respectively sent to the mixer by a gear pump so as to have a volume ratio of 1: 1 and then supplied from the through-hole 5 of the mold 2 to the inside of the mold 2 using a nozzle. did. The temperature of the reaction stock solution was 30 ° C., and its viscosity was 300 cps at 30 ° C.

Immediately after the completion of the supply of the reaction stock solution, the drive rollers 12, 14 were rotated, and the mold 2 was rotated around its axis. In 15 seconds, the rotation speed of the mold 2 becomes 120 rpm
And maintained that speed. The acceleration acting on the reaction stock solution was calculated to be 3G.

After maintaining this state for 5 minutes, the rotation was stopped, the mold 2 was taken out, the rolling rings 8, 8 were removed, and the split dies 4, 4 were opened. As shown in FIG. Such a tubular molded body 10 was obtained. The thickness of the molded body is
It was 10 mm.

For confirmation, the tubular molded body 10 was cut at a plurality of locations and the cross-sectional state was examined. No void was confirmed. When the inner peripheral surface of the tubular molded body 10 was observed, poor curing and the like were observed. It was confirmed that there was no defect and the surface was smooth. The bondability with the resin member 7 was also good. Further, when the roundness of the cross section of the hollow portion of the tubular molded body was measured, it was close to a perfect circle, and it was confirmed that favorable roundness was obtained.

A plurality of the tubular molded bodies 10 manufactured as described above are prepared, and the end faces are abutted with each other.
The opposing resin members 7 were heated and fused. It was confirmed that the joining property and the sealing property of the tubular molded bodies 10 were good.

Example 2 5 kg of silica sand (RS-silica manufactured by Tatsumori, average particle size: 1 mm) as a filler was put into a mold 2, and then a split mold 4 was prepared.
In the same manner as in Example 1 except that a total of 5 kg of the undiluted reaction solution was supplied to the inside of the mold 2 by using a nozzle from the axial through hole 5, a tube-shaped molding having a resin member 7 integrally therewith was performed. The body was molded.

For confirmation, the tube-shaped molded body was cut at a plurality of locations and the cross-sectional state was examined. No void was confirmed, and it was confirmed that silica sand as a filler was uniformly dispersed. . In addition, when the inner peripheral surface of the tube-shaped molded body 10 was observed, it was confirmed that there was no trouble such as poor curing and the surface was smooth. The bondability with the resin member 7 was also good. Further, when the roundness of the cross section of the hollow portion of the tubular molded body was measured, it was close to a perfect circle, and it was confirmed that favorable roundness was obtained.

Example 3 A tube-shaped molded article integrally including the resin member 7 was formed in the same manner as in Example 1 except that an ethylene vinyl chloride copolymer tube was used as the resin member 7.

For confirmation, the tubular molded body 10 was cut at a plurality of locations, and the cross-sectional state was examined. No void was confirmed, and the inner peripheral surface of the tubular molded body 10 was observed. It was confirmed that there was no defect and the surface was smooth. The bondability with the resin member 7 was also good. Further, when the roundness of the cross section of the hollow portion of the tubular molded body was measured, it was close to a perfect circle, and it was confirmed that favorable roundness was obtained.

A plurality of the tubular molded bodies 10 manufactured as described above are prepared, and the end faces are abutted to each other in a state where the adhesive is applied to the opposing end faces.
Was adhered. It was confirmed that the joining property and the sealing property of the tubular molded bodies 10 were good. As the adhesive, one obtained by dissolving a vinyl chloride resin in an organic solvent such as acetone, cyclohexanone, and tetrahydrofuran was used.

Example 4 A mold 22 shown in FIG. 6 was prepared and set on the driving rollers 12 and 14 of the mold rotating device shown in FIGS. The pair of split dies 24, 24 were made of an aluminum casting, had an outer diameter of 500 mm, an inner diameter of 400 mm, and an axial length of 1200 mm.

The nesting mold 29 was made of cast iron, and its axial dimension (height) was 82 mm. Split mold 24, 24
The axial dimension (depth) of the small diameter portion 24b was 82 mm. The inner diameter of the through holes 25a, 25b of the end plates 26a, 26b was 150 mm.

The water-stop packing (resin member) 27 is divided into two molds.
The split plates 24, 24 are assembled with the split surface 23 in a state where the split plates 24, 24 are arranged along the cutouts 24c of the end plates 26b.
Was fixed with screws. A silicone rubber sealing material was attached to the split surface 23.

An annular ring is used as the water stopping packing 27. The outer diameter of a cross section cut along a plane including the center axis is 422 mm, and the outer diameter on a plane orthogonal to the center axis is 41.
The thing of 6 mm was used. The material of the packing 27 for waterproofing was formed from an alternating copolymer having an equimolar ratio of isobutylene and maleic anhydride in consideration of the bondability with a molded product made of a reaction stock solution containing a norbornene-based monomer. .

In this state, the rolling rings 28, 28 were attached. The rolling rings 28, 28 are made of cast iron, have an outer diameter of 700 mm, and an axial thickness of 50 mm.
Met.

The rolling rings 28, 28 are connected to the driving rollers 12,
14, and 15 kg of the undiluted reaction solution was supplied into the mold 22 from the through holes 25 a and 25 b of the mold 22 using a nozzle. The preparation of the reaction stock solution was performed as follows. A mixed monomer composed of 85% by weight of dicyclopentadiene (DCP) and 15% by weight of tricyclopentadiene was used, and a styrene-isoprene-styrene block copolymer (Clayton 1170, Shell Co., Ltd.) was used based on 100 parts by weight of the total amount of the monomers. 5 parts by weight) and 2 parts by weight of Irganox 1010 (manufactured by Ciba-Geigy), which is a phenolic antioxidant, are placed in two containers, and one of them is mixed with diethyl aluminum chloride based on the mixed monomer. (DEAC) at a concentration of 40 mmol (millimolar equivalent to 1 mol of the mixed monomer is hereinafter referred to as "mmol concentration").
), N-propanol was added to a concentration of 44 mmol, and silicon tetrachloride was added to a concentration of 20 mmol (A
liquid). On the other hand, tri (tridecyl) ammonium molybdate was added to the mixed monomer at a concentration of 10 mmol (solution B).

The liquid A and the liquid B are respectively sent to the mixer by a gear pump so as to have a volume ratio of 1: 1. Then, a nozzle is inserted into the mold 22 through the through holes 25a and 25b of the mold 22. Supplied. The temperature of the reaction stock solution is 30
° C and its viscosity was 300 cps at 30 ° C.

Immediately after the completion of the supply of the reaction solution, the drive rollers 12 and 14 were rotated, and the mold 22 was rotated about its axis. In 15 seconds, the rotation speed of the mold 22 becomes 120 r
pm and maintained that speed. The acceleration acting on the reaction stock solution was calculated to be 3G.

After maintaining this state for 5 minutes, the rotation is stopped, the mold 22 is taken out, the rolling rings 28, 28 are removed, the split dies 24, 24 are opened, and the nesting mold 29 is opened.
When the (end plate 26b) is removed, the joint insertion portion 30 is removed.
a and the tubular molded body 30 having the joint receiving portion 30b were obtained. The thickness of the molded body was 10 mm.

For confirmation, the tubular molded body 30 was cut at a plurality of locations and the cross-sectional state was examined. No void was confirmed, and the inner peripheral surface of the tubular molded body 30 was observed. It was confirmed that there was no defect and the surface was smooth. Further, when the roundness of the cross section of the hollow portion of the tubular molded body was measured, it was close to a perfect circle, and it was confirmed that favorable roundness was obtained.

A plurality of the tubular molded bodies 30 manufactured as described above are prepared, and the joint inserting section 30a of the other tubular molded body 30 is inserted into the joint inserted section 30b of one tubular molded body 30. In this way, they were sequentially connected and connected. The work was extremely simple, and when a water flow was circulated inside, it was confirmed that the water stopping property of the connection portion was good.

[0114]

As described above, according to the present invention, it has excellent characteristics such as high rigidity and impact resistance, and
It is possible to manufacture a tubular molded body capable of realizing a connection excellent in the sealing property and the water stopping property of the connecting portion. In addition, since there is no protrusion or the like on the outer peripheral portion, it is possible to manufacture a tubular molded body suitable for piping work by the propulsion method.

[Brief description of the drawings]

FIGS. 1A and 1B are schematic perspective views of a mold used in a reactive polymerization molding method according to an embodiment of the present invention, and FIG. 1C is a schematic sectional view thereof.

FIG. 2 is a side view of a driving device for rotating a mold.

FIG. 3 is a plan view of a driving device.

FIG. 4A is an external perspective view showing an example of a molded body,
FIG. 1B is a cross-sectional view taken along line bb of FIG. 1A, and FIG. 1C is a cross-sectional view taken along line cc of FIG.

FIG. 5 is an enlarged sectional view of a connecting portion of a piping tube and the vicinity thereof.

FIG. 6 is a schematic sectional view of a mold used in a reactive polymerization molding method according to another embodiment of the present invention.

[Explanation of symbols]

 2,22 ... Mold 3,23 ... Split surface 4,24 ... Split die 7,27 ... Resin member 8,28 ... Rolling ring 10,30 ... Molded body 12, 14 ... Drive roll 16 ... Transmission 18 ... Torque Inverter motor 20 ... Base

Claims (4)

[Claims] 1. A reaction stock solution is placed in a mold in which a resin member is arranged along at least one end in the axial direction of a substantially cylindrical mold, and the mold is rotated to centrifuge the reaction stock solution. A reactive polymerization molding method, wherein reaction polymerization is performed while applying force. 2. The reactive polymerization molding method according to claim 1, wherein the resin member is made of a heat-fusible resin. 3. The reactive polymerization molding method according to claim 1, wherein the resin member is made of a water-swellable resin. 4. The resin member is integrally provided on an outer peripheral surface of at least one end in a longitudinal direction.
A tubular molded article produced by the reactive polymerization molding method according to any one of the above.