JPH0365319A - Manufacture of composite molded product - Google Patents

Abstract

PURPOSE:To integrate even a composite molded product having a three- dimensional or complicated shape with good productivity by molding an olefinic polymer and/or a hydrocarbon type thermoplastic elastomer into a layer forming material by vacuum molding or pressure molding and subsequently supplying norbornene type reaction solution for bulk polymerization to cure the same. CONSTITUTION:For example, a polypropylene sheet is cut into a proper size while the cut sheet is heated to be rapidly placed on a female mold and a mold is evacuated from the vacuum hole provided to the lower part thereof the bring the sheet into close contact with the mold surface. After layer forming material is molded into a box shape by vacuum molding, the mold is clamped and both of a reaction liquid containing an activator and a norbornene type monomer and a reaction solution containing a metathesis catalyst and the norbornene type monomer are mixed to be injected in the mold and polymerization reaction is performed to obtain a box-shaped composite molded product consisting of the polymer base material and the PP layer.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a method for manufacturing a composite molded article, and more specifically, to a method for manufacturing a composite molded article, and more specifically, a method for manufacturing a composite molded article, and more specifically, a method for manufacturing a composite molded article, and more specifically, a method for manufacturing a composite molded article, and a method for manufacturing a composite molded article. ) in the same mold, and by using a specific combination of layer forming material and base material,
The present invention relates to a method for manufacturing composite molded products with high productivity and excellent adhesion.

[Prior art] Plastic sandwich boards, which are made by laminating plastic as a core material and metal or hard plastic as a surface material, are widely used as lightweight composite materials. Productivity is low because it is manufactured by hot pressing using an adhesive.

Recently, a method has been proposed for manufacturing plastic sandwich plates by injecting a reaction solution containing a norbornene monomer and a metathesis catalyst between the surface materials using the RIM method and polymerizing the mixture (JP-A-62-122718). )
. However, in this method, the surface material is a metal plate or hard plastic plate (epoxy resin, phenolic resin,
Because a plastic plate made of unsaturated polyester reinforced with glass fiber, etc., is used, its adhesion to the core polymer tends to be insufficient. It is difficult to freely control the thickness of the material, or to laminate surface materials to suit the shape of the core when the shape is complex.

On the other hand, molded products obtained by bulk polymerizing norbornene-based monomers in a mold using the RIM method usually have a back color or brown color, and even if pigments are added and colored, the color tone will change over time. Easy to occur. Even if attempts were made to modify the surface condition of molded products by laminating colored plastic sheets or printed sheets, this method is still impractical due to the bulk polymers of norbornene monomers and poor adhesion. Composite materials have not been obtained.

Therefore, the present inventors developed a composite material in which a base material made of a bulk ring-opened electrolyte of a norbornene monomer is provided with a shoe made of an olefin polymer and/or a hydrocarbon thermoplastic elastomer. We proposed this and filed a patent application (Japanese Patent Application No. 171038/1983). This composite material has good front adhesion, the right color of the surface layer can be adjusted freely, weather resistance is improved, there is no sinkage, etc.
It has excellent properties.

By the way, this composite material is produced by bulk ring-opening polymerization by supplying a reaction stock solution containing a tricyclic or higher norbornene monomer and a metathesis catalyst to a mold equipped with a layer-forming material made of an olefin polymer, etc. However, in the case of complex shapes, it is necessary to place a layer-forming material obtained by forming a film, sheet, etc. into a specific shape by vacuum forming in advance in a mold. However, with this method,
The layer forming material formed by vacuum forming is removed from the mold and placed in the RIM mold, which is a complicated operation.Moreover, when the layer forming material is thin, removing the mold is troublesome and it is difficult to maintain the shape. be.

[Problem to be solved by the invention]

SUMMARY OF THE INVENTION An object of the present invention is to provide a method for manufacturing a composite molded article in which a layer-forming material and a bulk polymer are combined with each other with good operability.

As a result of intensive research in order to overcome the above-mentioned problems, the present inventors have found that an olefinic polymer and/or a hydrocarbon-based thermoplastic elastomer is used as the polymer material constituting the layer forming material, and a bulk polymer is also used. A polynorbornene-based resin is selected as the material, and the layer forming material is formed by vacuum forming or pressure forming, and the bulk polymer that becomes the base material is formed by reaction injection molding in the same mold. The present inventors have discovered that even composite molded products having a complex shape or shape can be manufactured in an integrated manner with good productivity, and based on this knowledge, the present invention has been completed.

[Means for Solving the Problems] Thus, according to the present invention, a bulky reaction liquid is supplied and cured into a mold having a split structure in which a layer forming material is disposed, and the layer forming material is cured. In producing a composite molded product in which the self-bond is integrated, a sheet or film made of an olefinic polymer and/or a hydrocarbon thermoplastic elastomer is closely adhered to at least one split mold by vacuum forming or pressure forming to form a predetermined shape. After forming into a layer forming material,
A method for producing a multi-named molded article is provided, which is characterized by supplying a reaction solution for bulk polymerization containing a tricyclic or higher norbornene monomer hymetathesis catalyst system to a cavity in a mold and curing it. The components of the invention will be explained in detail.

(Lumpy composite material reaction liquid) In the composite molded article of the present invention, the bulky composite material serving as the base material is a polynorbornene resin.

Molded products made from polynorbornene resin are produced by mixing two or more types of low-viscosity raw materials that react with photoresistivity and quickly producing polymers, then feeding the mixture into a closed mold (mold) and hardening it inside the mold. It can be manufactured by the so-called RIM method. For example, a reaction solution containing an activator, a hinorbornene monomer, and a metathesis catalyst, a reaction solution containing a hinorbornene monomer, are used as the reaction solution, and both solutions are mixed and supplied into a mold to perform bulk ring-opening polymerization. A polynorbornene resin molded product is obtained.

Molding of polynorbornene resin using the RIM method requires significantly lower injection pressure than injection molding of ordinary thermoplastic resins, so it is possible to use inexpensive and lightweight molds, and it also improves the fluidity of raw materials within the mold. It is preferable for producing large molded products or molded products with complicated shapes.

The polynorbornene resin that serves as the base material in the present invention is
Manufactured using tricyclic or higher polycyclic norbornene monomers. By having a tricyclic or higher polymer, a polymer having a high heat distortion temperature can be obtained and the heat resistance required as a composite material can be satisfied. Furthermore, in the present invention, the produced polymer can be thermosetting, and for this purpose at least 10% by weight, preferably 30% by weight or more of crosslinking monomers based on the total monomers may be used.

Examples of norbornene monomers having tricyclic or higher types include bicyclics such as dicyclopentadiene and dihydrodicyclopentadiene, tetracyclics such as tetracyclododecene, pentacyclics such as tricyclopentadiene, Heptacyclics such as tetracyclopentadiene, alkyl-substituted products (e.g., methyl, ethyl, propyl, butyl substituents, etc.), alkylidene-substituted products (e.g., ethylidene-substituted products, etc.), aryl-substituted products (e.g., phenyl-substituted products, etc.), , tolyl, naphthyl substituted products, etc.).

Among these, bicyclics to pentacyclics are preferred from the viewpoint of ease of availability, reactivity, heat resistance, etc.

The crosslinking monomer is a polycyclic norbornene monomer having two or more reactive double bonds, and specific examples thereof include dicyclopentadiene, tricyclopentadiene, and tetracyclopentadiene. therefore,
When the norbornene monomer and the crosslinking monomer are the same, it is not necessary to use any other crosslinking monomer.

Note that bicyclic norbornene monomers such as 2-norbornene or monocyclic cycloolefins such as cyclobutene, which can undergo ring-opening polymerization together with one or more of the tricyclic or more norbornene monomers mentioned above, may impede the purpose of the present invention. Can be used together within the range.

The catalyst used may be any metathesis catalyst system known as a catalyst for ring-opening polymerization of norbornene monomers, and specific examples include halides, oxyhalides, oxides, and organic ammoniums such as tungsten, molybdenum, and tantalum. Metathesis catalysts such as salts may be mentioned, and specific examples of activators (cocatalysts) include alkyl aluminum halides, alkoxyalkylaluminum halides, aryloxyalkylaluminum halides, organotin compounds, and the like.

The amount of the metathesis catalyst is usually about 0.01 to 50 mmol, preferably 0.01 to 50 mmol per mol of the norbornene monomer.
．． It is used in a range of 1 to 10 mmol. The activator (cocatalyst) is preferably used in an amount of 2 to 10 (molar ratio) based on the catalyst component.

Both the metathesis catalyst and the activator are preferably used after being dissolved in a monomer, but they may also be used after being suspended or dissolved in a small amount of a solvent as long as the properties of the product are not essentially impaired.

In a preferred method for producing polynorbornene resins, a norbornene monomer having three or more rings is divided into two liquids, placed in separate containers, a metathesis catalyst is added to one, and an activator is added to the other, and two types of stable monomers are added. Prepare a reaction solution. These two types of reaction solutions are mixed, and then a mold or formwork of a predetermined shape (
Both are injected into a mold (together referred to as a mold), where ring-opening polymerization takes place in bulk.

Additives such as antioxidants, fillers, reinforcing materials, foaming agents, pigments, colorants, and elastomers can be added to the polynorbornene resin. These additives are usually
It is blended by being dissolved or dispersed in the reaction solution, but it may also be placed in a mold.

When the base material is a foam, a foaming agent is added to the reaction solution,
Inject this into the mold. Preferred blowing agents are normally liquid, easily volatile, low-boiling organic compounds, such as hydrocarbons such as pentane, hexane, methylene chloride,
Examples include halogenated hydrocarbons such as trichlorofluoromethane and dichlorodifluoromethane, and inert gases such as nitrogen and argon.

(M-forming material) The polynorbornene-based resin of the base material on the layer-forming material needs to have good mutual adhesiveness. Therefore, in the present invention, a sheet or film made of an olefin polymer and/or a hydrocarbon thermoplastic elastomer is selected and used as the polymer material for the layer forming material.

Any desired thickness of the film or sheet can be used as long as the film or sheet can be vacuum-formed or pressure-formed.

Additionally, if you use sheets that have been colored in any color by adding pigments, printed sheets, or sheets that have been patterned by embossing, etc., you can obtain composite molded products with the desired surface condition. . When a transparent sheet or film is used as the surface layer, a composite molded product that retains the color tone of the base material can be obtained.

Specific examples of olefin polymers include high density polyethylene (PE), medium density PE, low density PE, ethylene-propylene copolymer, ethylene-butene-1 copolymer, polypropylene (pp), and polybutene. -1, polybentene-1, poly4-methylpentene-1, boristine, ethylene-propylene rubber (EPR), ethylene-propylene-diene terpolymer (EPDM), etc., or ethylene-vinyl acetate copolymer Examples include copolymers with ester monomers containing olefin monomers as a main component, such as ethylene-acrylic acid ester copolymers. The elastomer in the above olefinic polymer is used in the form of a crosslinked polymer or partially crosslinked polymer.

Among these olefin polymers, plastics have better adhesiveness to the substrate than crosslinked elastomers. However, a mixture consisting of a partially crosslinked elastomer such as EPR or EPDM and an appropriate amount of a plastic such as PE or PP has the properties of a thermoplastic elastomer; It is possible to obtain a layer with elastomeric properties without impairing its adhesive properties.

In addition, specific examples of hydrocarbon-based thermoplastic elastomers include various blocks composed of vinyl aromatic compounds represented by ethylene (S) and conjugated dienes such as isobutinone (■) and butadiene (B). Examples include copolymers,
Specifically, type S-I, type S-B, type 5-I-3, type 5-
Examples include B=S type, S-I-5-I-S type, and hydrides thereof. These hydrocarbon thermoplastic elastomers can be used alone or in combination of two or more.

Furthermore, these hydrocarbon-based thermoplastic beads are
It can be used by mixing with the body olefin polymer in any proportion.

(Method for manufacturing a composite molded product) In the method for manufacturing a composite molded product of the present invention, a mold with a split mold structure is used. , or both, and a bulk polymerization reaction solution is supplied into the mold and cured.

In this case, the layer forming material is provided by closely adhering a sheet or film made of a polymeric material to at least one split mold by vacuum forming or pressure forming to form a layer forming material in a predetermined shape. Thereafter, a composite molded article is manufactured by supplying a reaction liquid for bulk polymerization into the void in the mold and curing it.

The mold may be made of metal, resin, etc., or may be a simple mold. However, if the layer-forming material is a thin film, it is preferable to use a metal mold; if a resin mold is used, it is difficult to obtain a smooth surface.

In addition, at least one split mold (e.g., core or cavity) has a structure provided with vacuum holes and/or exhaust holes, compressed air introduction holes, etc., so that vacuum forming or pressure forming can be performed. .

Vacuum forming or pressure forming can be performed according to a conventional method. In vacuum forming, the sheet is cut to an appropriate size, heated and softened in advance, clamped onto a male mold and/or female mold, and the gap between the mold and the sheet is quickly evacuated. The sheet is molded in close contact with the inner surface of the mold. In pressure molding, both a male mold and a female mold are used, a sheet that has been heated and softened in advance is sandwiched between the two molds, one mold is evacuated, and the other mold is heated with compressed air for 5 to 6 k.
Apply a pressure of g/Cd to bring the sheet into close contact with the inner surface of one mold.

In normal vacuum forming or pressure forming, the molded product is removed from the mold after molding, but in the present invention, the layer forming material molded into a predetermined shape is kept in close contact with the mold, and if the split mold is open, it can be split. A composite molded article is produced by fitting the molds together, closing the molds, and then supplying a reaction liquid for bulk polymerization into the voids in the molds and curing them. Therefore, for example, when vacuum forming a layer forming material into a box shape using a cavity mold, the core mold is moved to close the mold, and then a reaction liquid is supplied into the mold and cured. It is possible to produce a composite molded article having a structure in which a layer forming material is in close contact with the surface layer of a box-shaped bulk polymer. Furthermore, when pressure forming is performed with the mold closed, a composite molded article can be produced by supplying the reaction liquid to the voids of the mold and curing it.

As is clear from the foregoing, the polynorbornene resin serving as the base material can be molded by the usual RIM method by supplying a reaction solution into a metal mold and curing it. As a supply method, two or more reaction solutions are
Either the mixture is instantaneously mixed in the mixing head of an IM machine and then injected into a hot mold, or if the reaction solution has a long pot life, mixing is completed in a mixer and then preheated. It may be injected or poured into a mold once or several times. These operations are performed under an inert gas atmosphere if necessary.

[Effect]

According to the manufacturing method of the present invention, an olefinic polymer and/or hydrocarbon elastomer is used as a layer forming material in combination with a polynorbornene resin as a base material, and vacuum forming or pressure forming and reaction injection molding are performed. By using these in combination, it is possible to easily produce a composite molded product with a three-dimensional shape or a complex shape that is firmly bonded at the interface.

In a method in which a layer-forming material such as a film or sheet is separately formed into a predetermined shape by vacuum forming or the like and placed in a reaction injection mold, the layer-forming material is removed from the mold and placed in a RIM mold. The operation for disposing the layer is complicated, and when the layer forming material is thin, it is difficult to demold and maintain the shape. However, the method of the present invention does not have such problems and has high productivity. Composite molded products can be manufactured.

[Examples] The present invention will be described in more detail with reference to Examples below, but the present invention is not limited only to these Examples. Note that parts, percentages, etc. are based on weight unless otherwise specified.

[Example 1] A sheet of polypropylene (PP, Shortlex FA-110 manufactured by Showa Denko) with a thickness of 3 mm was cut into an appropriate size, heated to 200°C with a heating plate, and then immediately placed on a female mold. placed. The mold temperature was 80°C. Next, the vacuum valve was opened to evacuate through the vacuum hole provided at the bottom of the mold, and the sheet was brought into close contact with the mold surface.

The shape of the female mold is a trapezoidal box, with 200 mm at the bottom of the mold.
mmX 100mm, mold opening 300mmX 1
The length was 50 mm and the height was 100 mm. The space between the male and female molds was 6 mm.

After forming the layer forming material into a box shape by vacuum forming, the core mold was moved and the mold was closed.

2% of Irganox 259 (manufactured by Ciba Geigy), a phenolic antioxidant, was dissolved in dicyclopentadiene (hereinafter referred to as DCP).

This was placed in two containers, and to one was added diethylaluminum chloride (DEAC) at a concentration of 33 mmol, n-propanol at a concentration of 42.9 mmol, and silicon tetrachloride at a concentration of 20 mmol relative to the DCP. On the other hand, tri(tridecyl)ammonium molybdate was added to the DCP at a concentration of 4 mmol.

Both reaction solutions were mixed at a ratio of 1=1, and the layer-forming material was vacuum-formed and poured into a mold heated to 80°C. After injection, approx.
A polymerization reaction was carried out for a minute to obtain the box-shaped composite molded article consisting of a DCP polymer base material (3 mm thick) and a PP layer (3 mm thick). These series of operations were performed under a nitrogen atmosphere.

The thus obtained composite molded product had good adhesion between the base material and the PP layer, and was a molded product with no sink marks and excellent flatness. When trying to peel off the PP layer from this composite material,
No destruction was observed at the interface with the base material, and the base material layer was destroyed.

[Example 2] Instead of using a PP sheet, we used a 1mm thick polyethylene colored red! Non (PE, Shorex 108FS,
Using a sheet (manufactured by Showa Denko), preheat the sheet to 16
A composite molded article was obtained in the same manner as in Example 1 except that the temperature was 0°C.

The composite molded product with the PE sheet as the surface layer had excellent adhesive properties with no discoloration of the PE layer (if a PP sheet was used, as in the case of PP sheet), and an excellent surface condition with no sink marks.

[Effects of the Invention] According to the present invention, by performing molding of the layer forming material by vacuum forming or pressure forming and reaction injection molding of the polynorbornene resin as the base material in the same mold, three-dimensional or Even composite molded products with complex shapes can be manufactured with high productivity. Having good interfacial adhesion by the method of the present invention,
The surface layer can be colored freely, weather resistance is improved, and a composite molded product without sink marks can be obtained. This composite molded product can be used in a wide variety of applications such as automobile parts, electrical parts, and architectural parts.

Claims (1)

[Claims] (1) In producing a composite molded product in which the layer forming material and the bulk polymer are integrated by supplying the reaction liquid for bulk polymerization into a mold with a split structure in which the layer forming material is arranged and curing it, A sheet or film made of an olefin polymer and/or a hydrocarbon thermoplastic elastomer is closely attached to at least one split mold by vacuum forming or pressure forming to form a layer forming material of a predetermined shape, and then A method for producing a composite molded article, which comprises supplying and curing a bulk polymerization reaction solution containing a tricyclic or higher norbornene monomer and a metathesis catalyst system.