JP2002187138A - Method for manufacturing norbornene polymer molding - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a method for manufacturing a norbornene polymer molding having excellent mold releasability and productivity. SOLUTION: The method for manufacturing the norbornene polymer molding comprises the steps of introducing a resin composition 3 containing a norbornene monomer and a polymerization catalyst, as main components to an air gap part formed of an outer mold 1 and inner molds 2 and 21 made of a material having smaller linear expansion coefficient than that of a norbornene polymer; polymerizing the composition, molding the composition to the molding; then removing the mold 1; and releasing the molds 2 and 21 in a state in which a temperature of the molding is higher than a polymerization temperature of the composition 3.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

[0001] The present invention relates to a method for producing a norbornene-based polymer molded article.

[0002]

2. Description of the Related Art Conventionally, a method of manufacturing a fiber-reinforced plastic (FRP) molded article using an inner mold such as a core has been used when manufacturing a hollow molded article such as a pipe. There is a device that makes it easier to remove the core by using a device such as a split mold or a taper.

A thermosetting resin such as an unsaturated polyester resin or an epoxy resin used for the above-mentioned FRP molded article is:
There was a problem that the volume shrinkage due to the reaction was large, and the inner mold was tightened or deformed, such as sink marks, making it difficult to remove from the inner mold.

Further, filament winding (F
W) In molding, a mandrel as a core is used. In the case of FW molding, a tension is often given to the molding material by winding, and a large residual stress remains in the molded body after molding, and the mandrel is tightened, so that the mold cannot be easily removed. Therefore, it is necessary to form a split mold or taper the mandrel. However, the split mold has a complicated structure, which increases the cost of the mold. In the case of the split mold, there is also a problem that the resin is caught in the cracks of the mold and it is difficult to remove the mold. In the case where a draft is formed by taper processing, a tapered shape which is not desired to be formed on a molded body is formed, which may impair the appearance or cause performance problems in connection with other parts. Further, there is a disadvantage that the radius of curvature of the curved portion of the molded product cannot be reduced from the viewpoint of the mold releasing property.

Japanese Patent Application Laid-Open No. 5-104571 discloses that a mandrel is extracted from a fiber preform obtained by winding fibers around a core and is impregnated with a matrix resin by reaction injection molding to obtain a molded body. . However, in this case, since the tension caused by the wound fibers and the residual stress due to the curing shrinkage of the resin are applied to the core, it is not easy to remove the core from the molded body. In addition, when the resin comes around the end face, it is more difficult to remove the mold. If the core is made into an embedded type, the core does not need to be removed, but the core cannot be reused, which increases the cost, and the core must be manufactured each time it is formed.

[0006]

SUMMARY OF THE INVENTION An object of the present invention is to provide a method for producing a norbornene-based polymer molded article having excellent demoldability and productivity.

[0007]

Means for Solving the Problems One of the methods for producing a norbornene-based polymer molded article of the present invention is to provide a method for producing a void portion formed by an outer mold and an inner mold made of a material having a smaller linear expansion coefficient than the norbornene-based polymer. Then, after introducing a resin composition containing a norbornene-based monomer and a polymerization catalyst as main components and polymerizing to form a molded body, the outer mold is removed, and the temperature of the molded body is higher than the polymerization temperature of the resin composition. It is characterized in that it is released from the inner mold.

[0008] Another production method according to the present invention is a method for producing a molded product by polymerizing a reinforcing material impregnated with a resin composition containing a norbornene-based monomer and a polymerization catalyst as main components in a state of being laminated or wound on the surface of a molding die. After that, the molding is released from the molding die in a state where the temperature of the molding is higher than the polymerization temperature of the resin composition.

The norbornene-based polymer can be obtained by subjecting a norbornene-based monomer to metathesis polymerization using a polymerization catalyst, and is a polymer having excellent impact resistance, heat resistance, and chemical resistance. In addition, since the norbornene-based monomer is polymerized by ring-opening polymerization using a metathesis polymerization catalyst, residual stress is less likely to remain because the volume shrinkage is smaller than when a normal thermosetting resin is used. It has the characteristic of being small.

Examples of the norbornene-based monomer include bicyclics such as 2-norbornene and norbornadiene, tricyclics such as dicyclopentadiene and dihydrodicyclopentadiene, tetracyclododecene, ethylidenetetracyclododecene, and phenyltetracyclododecene. Such as tetracyclic, pentacyclic such as tricyclopentadiene, heptacyclic such as tetracyclopentadiene, and their alkyl-substituted (eg, methyl, ethyl, propyl, butyl-substituted etc.), alkylidene-substituted (eg, , Ethylidene-substituted), aryl-substituted (for example, phenyl and tolyl-substituted), epoxy group, methacrylic group, hydroxyl group, amino group, carboxyl group, cyano group, halogen group, ether group and ester bond-containing group. And derivatives having the formula: In particular, dicyclopentadiene has an excellent balance of physical properties such as reactivity and heat resistance when polymerized,
It is preferable because it has excellent impact resistance. These may be used alone or in combination of two or more.

A ring-opening polymerizable monocyclic cycloolefin such as cyclobutene, cyclopentene, cyclopentadiene, cyclooctene, cyclooctadiene, cyclododecene, cyclododecatriene, or indene, cumarone, or one or more of norbornene monomers. A cyclic monomer such as a coumarone-indene comonomer can be used as long as the object of the present invention is not impaired. A crosslinkable cyclic monomer such as tetrahydroindene may be used in combination.

Examples of the polymerization catalyst for the norbornene-based monomer include a metathesis polymerization catalyst, and include halides, oxyhalides, such as tungsten, molybdenum, tantalum, ruthenium, rhenium, osmium, and titanium.
Oxides, organic ammonium salts and the like.

As the polymerization catalyst, in addition to the above-mentioned ones, the following ones having excellent stability against air and moisture can be mentioned, and they are advantageous when they are combined with a reinforcing material or applied to various processes as in the present invention. It is. Specifically, a ruthenium carbene catalyst represented by the following general formula [I] and a ruthenium vinylidene catalyst represented by the following general formula [II] are preferable.

[0014]

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[0015]

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Wherein R ₁ and R ₂ independently of one another are hydrogen, C2-C20-alkenyl, C1-C20-alkyl, aryl, C1-C20-carboxylate, C1
-C20-alkoxy, C2-C20-alkenyloxy, aryloxy, C2-C20-alkoxycarbonyl, C1-C20-alkylthio, C1-C20-alkylsilyl, arylsilyl, thioaryl, thioalkyl (alkyl portion is C1-C20), Oxyaryl, oxyalkyl (the alkyl part is C1 to C20)
(These are C1-C5-alkyl, halogen, C1-C5
By C5-alkoxy or optionally C1-C
It may be optionally substituted by 5-alkyl, halogen, phenyl substituted by C1-C5-alkoxy. ), A ferrocene derivative, X ₁ and X ₂ independently of one another and any desired anionic ligand, L ₁ and L ₂ independently of one another and any desired neutral electron donor And two or three of X ₁ , X ₂ , L ₁ and L ₂ may further form together a polydentate chelating ligand. ]

A more preferred structure of the catalyst is represented by the general formula [I]
And in the general formula [II], R ₁ and R ₂ are each independently hydrogen, methyl, ethyl, phenyl, ferrocenyl,
Or vinyl optionally substituted by methyl, ethyl, ferrocenyl, X ₁ and X ₂ are each independently Cl, Br, and L ₁ and L ₂ are each independently trimethylphosphine, triethylphosphine, toluene. Phenylphosphine, triisopropylphosphine or tricyclohexylphosphine.

Since the amount of the metathesis catalyst varies depending on the activity of the catalyst, it cannot be specified unconditionally, but is preferably 1/5 to 1 / 500,000 molar equivalents relative to all monomers. When the amount is more than 1/5 equivalent, the molecular weight of the obtained polymer does not increase, and when the amount is less than 1 / 500,000 equivalent, the polymerization rate is undesirably reduced. A more preferable addition amount is 1/100 to 1 with respect to all monomers.
/ 100,000 molar equivalents. The mixing ratio of the catalyst may be set based on the necessary pot life and curing time in this range.

The above norbornene-based monomers may include, if necessary, an antioxidant, a filler, a foaming agent, an antifoaming agent, a thixotropic agent, an antistatic agent, a molecular weight modifier, a polymer modifier, a flame retardant, Various additives such as a plasticizer, a pigment, a dye, a colorant, a surface treatment agent, a dispersant, and an elastomer can be blended.

Examples of the filler include calcium carbonate, aluminum hydroxide, magnesium carbonate, sodium hydrogen carbonate, clay, talc, mica, kaolin, fly ash, montmorillonite, glass balloon, silica balloon, thermally expandable vinylidene chloride particles and the like. Can be

Examples of the elastomer include natural rubber, polybutadiene, polyisoprene, styrene-butadiene-styrene block copolymer, styrene-isoprene-styrene block copolymer, EPDM, ethylene-vinyl acetate copolymer and hydrides thereof. No.

Examples of the material having a lower linear expansion coefficient than the norbornene-based polymer include copper, nickel, aluminum, iron, and stainless steel. For example, if the linear expansion coefficient of polydicyclopentadiene obtained by polymerizing dicyclopentadiene is about 8.5 × 10 ⁻⁵ and the inner die has a linear expansion coefficient of 3 × 10 ⁻⁵ or less, molding The mold can be easily removed in a state where the body temperature is high, and the productivity can be improved.

Further, when the inner mold is cooled by circulating cooling water at the time of demolding by using an inner mold having a cooling pipe provided therein, the inner mold shrinks and the removability can be further improved. It is preferred.

The reinforcing material used in the invention of claim 2 includes:
It may be a continuous fiber such as roving, roving cloth or chopped strand mat, or may be a long or short fiber such as chopped strand or milled fiber. Fiber types include inorganic fibers such as glass fiber, carbon fiber, and metal fiber, and organic fibers such as aramid fiber, nylon fiber, shoot fiber, kenaf fiber, bamboo fiber, polyethylene fiber, drawn polyethylene fiber, polypropylene fiber, and drawn polypropylene fiber. Fiber.

Next, an example of a method for producing a norbornene-based polymer molded article according to claim 1 will be described with reference to the drawings. 1 to 3 show steps of manufacturing a branch joint for piping. An outer mold 1 that can be divided into two as shown in FIG.
And a resin composition 3 comprising a norbornene-based monomer and a polymerization catalyst are injected into a gap formed between the inner mold 2 having a smaller coefficient of linear expansion than the norbornene-based polymer, and the resin composition 3 is polymerized in that state. By curing, the polymer molded body 31 is obtained. When the molded body 31 is removed from the mold, the outer mold 1 is first released to release the molded body 31 from external restraint, and when the temperature of the molded body 31 is higher than the polymerization temperature of the resin composition 3, the inner mold 2 is removed. A gap is generated between the inner mold 2 and the molded body 31 due to the difference in the coefficient of linear expansion between the molded body 31 and the molded body 31, and the releasability is greatly improved.

The polymerization temperature of the resin composition is preferably as low as possible in comparison with the time of demolding. This is due to the fact that the shape of the polymer is almost fixed during the polymerization and curing stages, the temperature difference from the temperature during the subsequent demolding increases, and the difference in the amount of linear expansion between the inner mold and the molded body increases, resulting in more demolding. This is because the moldability is improved.

The temperature difference between the temperature at which the resin composition is polymerized and the temperature at which the resin composition is removed from the molded product is preferably 20 ° C. or more. If this temperature difference is smaller than 20 ° C., it is difficult to create a sufficient space for demolding.

Next, an example of the manufacturing method according to claim 2 will be described with reference to FIGS. FIGS. 7 and 8 are cross-sectional views showing steps of manufacturing a bathtub. A resin-impregnated fiber mat 8 impregnated with a resin composition containing a norbornene-based monomer and a polymerization catalyst as main components is laminated on the surface of a mold 7. Is obtained, a bath 81 made of a norbornene-based polymer reinforced with fibers is obtained. When removing the bathtub 81, the temperature of the bathtub 81 is set to a temperature higher than the temperature at the time of polymerization of the resin-impregnated fiber mat 8. Accordingly, a gap is formed between the molding die 7 and the bathtub 81 due to a difference in the amount of linear expansion therebetween, and the resistance when the mold is released is extremely small. In the manufacturing method in this case, it is possible to reduce the radius of curvature of the corner part and eliminate the taper with a shape like a bathtub or a waterproof pan, and to improve the watertightness of the fitting part of the bathroom unit. Is possible.

(Function) According to the first aspect of the present invention, the molded body cured in the gap between the outer mold and the inner mold is released from the mold using the inner mold having a smaller linear expansion coefficient than the norbornene-based polymer. At this time, first, the outer mold is released to release the restraint from the outside, and if the temperature of the molded body is higher than the temperature at the time of polymerization, the linear expansion amount between the molded body and the inner mold is different. And the mold can be easily removed. Accordingly, there is no need to provide a taper or split mold for the inner mold, and the structure of the inner mold can be simplified. Further, the curvature at the corner of the molded body can be reduced. Since this method uses an outer mold and an inner mold, it can be applied to, for example, injection molding, BMC, and the like.

According to the second aspect of the present invention, since a mold having a smaller linear expansion coefficient than the norbornene-based polymer is used,
If the temperature of the molded body is higher than the temperature at the time of polymerization when the molded body cured on the mold surface is removed from the mold, the amount of linear expansion between the mold and the molded body is different, so a gap is created between the molds. Can be removed from the mold. Also, there is no need to provide a large taper in the molding die, and the curvature at the corners of the molded body can be reduced. According to this method, it can be applied to a molding method that does not use an outer mold. For example, it can be used for hand lay-up molding, spray-up molding, and FW molding of FRP.

[0031]

(Embodiment 1) As shown in FIG.
A cylindrical inner mold 4 for pipe production (75 mmφ × 65 cm,
Two outer molds 5 (S without taper, SUS)
US) was used. The temperature of the inner mold 4 and the outer mold 5 was 25 ° C. A solution prepared by dissolving 10 parts by weight of bis (tricyclohexylphosphine) benzylidene ruthenium dichloride in 200 parts by weight of toluene with respect to 100 parts by weight of dicyclopentadiene heated to 40 ° C. was treated with bis (tricyclohexylphosphine) benzylidene ruthenium dichloride dicyclopentadiene. It was added so that the molar ratio to pentadiene was 1/10000, and mixed to prepare a resin composition. As shown in FIG. 4, the resin composition 6 is filled in the space formed by the outer mold 5 and the inner mold 4 and heated at 80 ° C. for 30 minutes in a heating furnace (not shown). Only mold 5 was released (FIG. 5). After further heating at 80 ° C. for 10 minutes, the inner mold 4 was immediately removed from the mold. The inner mold 4 can be removed smoothly, and a pipe 61 made of norbornene-based polymer having an inner diameter of 75 mmφ and a length of 65 cm as shown in FIG. Obtained.

(Embodiment 2) A cooling pipe was disposed inside the inner mold used in the first embodiment, and the outer mold used in the first embodiment was used. The temperature of the inner mold and the outer mold was 25 ° C. And 40 ℃
A solution prepared by dissolving 10 parts by weight of a ruthenium vinylidene complex represented by the following formula [III] in 200 parts by weight of toluene with respect to 100 parts by weight of dicyclopentadiene heated to a temperature of 1 / 10,000 was used. Was added and mixed so as to obtain a resin composition. The resin composition was filled in the voids formed by the outer mold and the inner mold, and heated at 80 ° C. for 30 minutes in a heating furnace. First, only the outer mold was removed. Further, after heating at 80 ° C. for 10 minutes, cooling water at 5 ° C. was passed through the inner mold for a while, and then the inner mold was released. As a result, it was possible to remove the mold smoothly, and a pipe similar to that of Example 1 was obtained ( Not shown).

[0033]

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(Example 3) 1600 m provided with a temperature control pipe
A moulding mold 7 (nickel electroforming, draft angle of upright face 1.5 degrees, curvature of corner portion 1 mm) for preparing an m-size bathtub was prepared, and the temperature of this mold 7 was set to 25 ° C. Example 2
While impregnating the resin composition prepared in the above into a chopped strand mat of # 450, a resin-impregnated fiber mat 8 was laminated on the surface of the mold 7. After heating at 80 ° C. for 30 minutes, cooling water at 5 ° C. was passed through the mold 7 for a while, and then the mold was removed from the molded body 7.
An m-size bathtub 81 was obtained.

(Comparative Example 1) The demolding was attempted by simply heating the resin composition filled in the voids in Example 1 at 80 ° C for 30 minutes in a heating furnace. Since the outer mold was divided into two parts, it could be removed from the mold, but could not be removed from the inner mold.

(Comparative Example 2) A molding die (made of epoxy resin, draft of a standing surface) for manufacturing a bathtub of 1600 mm size.
5 °, the curvature of the corner portion was 1 mm), and the temperature of the mold was 25 ° C. A mixture of 100 parts by weight of ortho-unsaturated polyester resin and 1 part by weight of methyl ethyl ketone peroxide as a curing agent was laminated on the surface of a mold while impregnating a # 450 chopped strand mat with an impregnating roller. This was heated at 80 ° C. for 1 hour and then tried to be released, but could not be released.

[0037]

According to the present invention, an inner mold or a molding die made of a material having a smaller coefficient of linear expansion than a norbornene-based polymer is used, and the inner mold or the molding die is heated at a temperature higher than the polymerization temperature of the resin composition. Since the molded article is released from the mold, the molded article can be released without resistance. In addition, there is no need to split the inner mold or the forming die or to provide a taper, so that the degree of freedom in the shape design of the formed body is improved. Further, since the workability at the time of removing the mold is greatly improved, the productivity is increased, and the damage of the product at the time of removing the mold can be reduced. Further, it is possible to manufacture a product requiring a plurality of cores or a multi-cavity production.

[Brief description of the drawings]

FIG. 1 is a perspective view showing a state in which a gap between an outer mold and an inner mold is filled with a resin composition.

FIG. 2 is a perspective view showing a state where an outer mold of FIG. 1 is removed.

FIG. 3 is a perspective view showing a molded body from which the inner mold of FIG. 2 is removed.

FIG. 4 is a perspective view showing a state in which a resin impregnated reinforcing material is wound between an outer mold and an inner mold.

FIG. 5 is a perspective view showing a state where the outer mold of FIG. 4 is removed.

FIG. 6 is a perspective view showing a pipe from which the inner mold of FIG. 4 is removed.

FIG. 7 is a cross-sectional view showing a state in which a resin-impregnated fiber mat is laminated on the surface of a mold for producing a bathtub.

FIG. 8 is a cross-sectional view showing a state in which the bathtub formed in FIG. 6 is removed from a forming die.

[Explanation of symbols]

 1,5: Outer mold 2,21,4: Inner mold 3,6: Resin composition 7: Mould 8: Resin impregnated fiber mat 31: Pipe 61: Molded body 81: Bath tub

──────────────────────────────────────────────────続 き Continued on the front page (51) Int.Cl. ⁷ Identification symbol FI Theme coat ゛ (Reference) B29K 105: 06 B29C 67/14 EF term (Reference) 4F202 AA12 AJ11 AJ12 AR06 CA01 CB01 CN05 4F204 AA12 AD16 EA03 EA04 EB01 EB11 EF01 EF05 EK15 EK17 EK24 EK25 4F205 AA12 AB03 AD16 AG08 AG29 AJ11 HA02 HA03 HA14 HA25 HA33 HA45 HB01 HK04 HK05 HK08 HK32 HM02 4J032 CA34 CA38 CB01 CD02 CE06 CG07

Claims (5)

[Claims] 1. A resin composition containing a norbornene-based monomer and a polymerization catalyst as main components is introduced into a void portion formed by an outer mold and an inner mold made of a material having a smaller coefficient of linear expansion than a norbornene-based polymer. After polymerization to form a molded body,
A method for producing a norbornene-based polymer molded article, comprising removing an outer mold and releasing the molded article from the inner mold in a state where the temperature of the molded article is higher than the polymerization temperature of the resin composition. 2. A molding obtained by laminating or winding a reinforcing material impregnated with a resin composition containing a norbornene-based monomer and a polymerization catalyst as main components on a surface of a molding die to form a molded product, and then polymerizing the resin composition. A method for producing a norbornene-based polymer molded article, comprising releasing the molded article from the mold in a state where the temperature of the molded article is higher than the temperature. 3. The method for producing a norbornene-based polymer molded article according to claim 1, wherein the inner mold or the mold is released while being cooled. 4. The norbornene-based monomer is dicyclopentadiene, and the material of the inner mold or the mold has a coefficient of linear expansion of 3
The method for producing a norbornene-based polymer molded article according to any one of claims 1 to 3, wherein the density is × 10 ^-5 or less. 5. The norbornene-based polymer according to claim 1, wherein the polymerization catalyst is a ruthenium carbene complex represented by the following general formula [I] or a ruthenium vinylidene complex represented by the following general formula [II]: A method for producing a molded article. Embedded image Embedded image