JPH06297593A - Production of crosslinked polymer molded article having curved surface - Google Patents

Abstract

PURPOSE:To simply obtain a molded article having a curved surface of every kind corresponding to a purpose using a common mold by transferring a crosslinked polymer molded article to a shaping mold having a curved surface from a mold to shape and cool the same. CONSTITUTION:In a method for extremely easily obtaining a molded article having a curved surface by simultaneously performing the polymerization and molding of a metathesis polymerizable cyclic olefin in the presence of a metathesis polymerization catalyst using an inexpensive mold, a common mold for molding a planar plate is used in a first stage to obtain a flat molded article. This molded article is transferred to an extremely inexpensive shaping mold having a necessary curved surface in a hot state in a second stage and shaped to be cooled. The proper surface temp. of a crosslinked polymer molded article is 35--40 deg.C with respect to glass transition temp.

Description

Detailed Description of the Invention

[0001]

FIELD OF THE INVENTION The present invention relates to a method for producing a crosslinked polymer molding (hereinafter referred to as a molding) by simultaneously polymerizing and molding a metathesis-polymerizable cyclic olefin in a mold in the presence of a metathesis polymerization catalyst. At, it relates to a method for inexpensively and easily obtaining a molded article having a curved surface.

The molded article having a curved surface obtained by the present invention can be used for a curved concrete panel (hereinafter referred to as a control panel).

[0003]

It is known that cyclic olefins give ring-opening polymers by means of metathesis polymerization catalysts. Therefore,
A method has been proposed in which a liquid metathesis-polymerizable cyclic olefin, such as dicyclopentadiene, which can be obtained at low cost, is polymerized and molded in one step in a mold with a metathesis polymerization catalyst to obtain a polymer molded product. That is, the fact that the metathesis polymerization catalyst system is composed of two components, that is, a catalyst component such as tungsten chloride and an activator component such as an alkylaluminum halide is used, and two kinds of liquids consisting of these two components and a monomer are used. A method of obtaining a crosslinked polymer molded product (hereinafter referred to as a molded product) by a reaction injection molding method by collision mixing has been proposed (see, for example, JP-A-58-129013).

Such a method is industrially very attractive because a large-sized molded product having good performance can be obtained by using an inexpensive low-pressure molding die. In this method, as the mold usually used, metal spray mold such as nickel electroforming mold or zinc alloy, aluminum, metal casting mold such as zinc alloy,
There is a resin type. The mold used in this method is a thermoplastic resin injection molding mold or unsaturated polyester (SMC, etc.)
Although it is cheaper and more advantageous than the pressure-molding die, it is necessary to make a die corresponding to each shape if the shape of the molded article is different in any molding method. Therefore, when the required number of molded products of the same shape is small, the ratio of the depreciation cost of the mold price to the price of the molded products becomes large, and the merit of resinification decreases.

On the other hand, most of the control panel materials are made of steel. Besides, wood and resin are used. As a problem of these materials,
Steel is heavy and easily rusts. When wood is used, it causes environmental damage as represented by tropical rainforests, and with resin, it is necessary to prepare a mold according to the shape of the molded product as described above. . Especially for resin, reduction of mold cost including molding method is an important issue.

[0006]

SUMMARY OF THE INVENTION It is an object of the present invention to provide a method for easily obtaining a molded article having various curved surfaces from a common mold according to the purpose.

[0007]

MEANS FOR SOLVING THE PROBLEMS The present inventor has developed a metathesis-polymerizable cyclic olefin in the presence of a metathesis polymerization catalyst,
In the method of obtaining a molded article having a curved surface by simultaneously performing polymerization and molding in a mold, as a result of diligent examination of a molding method for reducing the mold cost and obtaining it very easily, Using a common mold for molding the plate, a flat plate molded product was obtained, and while it was still hot, it was transferred to an extremely inexpensive shaping mold having the necessary curved surface as the second stage, where it was shaped. It was found that a molded product having a desired curved surface can be obtained easily and inexpensively by shape cooling, and the present invention has been achieved.

That is, the present invention comprises a monomer solution (solution B) consisting of a metathesis polymerizable cyclic olefin containing a catalyst component of a metathesis polymerization catalyst system and a metathesis polymerizable cyclic olefin containing an activator component of a metathesis polymerization catalyst system. And a monomer liquid (solution A) is mixed, and the mixture is injected into a mold and polymerized to obtain a cross-linked polymer molded product having a surface temperature T (° C.) of Tg−40 ≦ T ≦ Tg + 35 [where Tg is It represents the glass transition temperature (° C) of a crosslinked polymer molded product. ], The crosslinked polymer molded product is transferred from the inside of the mold to a shaping mold having a curved surface and subjected to shape cooling, and the crosslinked polymer molded product having a curved surface is produced. The surface temperature T (° C.) of the crosslinked polymer molded product when the crosslinked polymer molded product is transferred to the shaping mold is more preferably Tg−35 ≦ T ≦ 30.

The metathesis-polymerizable cycloolefin used in the present invention has a metathesis-polymerizable cycloalkene group of 1
The one containing ~ 2 is used. Preferred is a compound having at least one norbornene skeleton in the molecule.

Specific examples of these include dicyclopentadiene, tricyclopentadiene, cyclopentadiene, methylcyclopentadiene co-dimer, 5-ethylidene norbornene, norbornene, norbornadiene, 5
-Cyclohexenyl norbornene, 1,4,5,8-dimethano-1,4,4a, 5,6,7,8,8a-octahydronaphthalene, 1,4-methano-1,4,4a,
5,6,7,8,8a-octahydronaphthalene, 6-
Ethylidene-1,4,5,8-dimethano-1,4,4
a, 5,6,7,8,8a-octahydronaphthalene,
6-ethylidene-1,4,5,8-dimethano-1,4
4a, 5,7,8,8a-heptahydronaphthalene,
1,4,5,8-dimethano-1,4,4a, 5,8,8
a-Hexahydronaphthalene-1, ethylenebis (5-
Norbornene) and the like, and mixtures thereof can also be used. In particular, a solution mainly composed of dicyclopentadiene or a mixture containing 50 mol% or more thereof is preferably used.

If necessary, a metathesis-polymerizable cyclic olefin having a polar group containing a different element such as oxygen or nitrogen can be used for the copolymerization. Such a copolymerizable monomer also preferably has a norbornene structural unit, and the polar group is preferably an ester group, an ether group, a cyano group, an N-substituted imide group, a halogen group or the like. Specific examples of such a copolymerizable monomer include 5-
Methoxycarbonylnorbornene, 5- (2-ethylhexyloxy) carbonyl-5-methylnorbornene, 5
-Phenyloxymethyl norbornene, 5-cyanonorbornene, 6-cyano-1,4,5,8-dimethano-1,
4,4a, 5,6,7,8,8a-octahydronaphthalene, N-butyl nadic acid imide, 5-chloronorbornene and the like can be mentioned.

The molding in the present invention is carried out by a monomer solution (solution A) consisting of a metathesis-polymerizable cyclic olefin containing a catalyst component of a metathesis polymerization catalyst system, and a metathesis polymerization cyclic compound containing an activator component of a metathesis polymerization catalyst system. Mixing with a monomer liquid (solution B) consisting of olefin,
Although it is a method of injecting into the mold, a method of dividing the solution into three or more is also possible.

Salts such as halides of metals such as tungsten, rhenium, tantalum and molybdenum are used as the catalyst component in the metathesis polymerization catalyst system in such molding, but tungsten compounds are particularly preferable. The tungsten compound is preferably tungsten hexahalide, tungsten oxyhalide, or the like, and more specifically, tungsten hexachloride,
Tungsten oxychloride and the like are preferable. Also,
Organic ammonium tungsten salts and the like can also be used. Such a tungsten compound may start cationic polymerization immediately when added directly to the monomer, and the tungsten compound is suspended in an inert solvent such as benzene, toluene or chlorobenzene in advance, and a small amount of an alcohol compound and / or a phenol compound. It is preferable to use it after solubilizing it by adding a compound.

Further, as described above, in order to prevent undesired polymerization, about 1 to about 1 mol of the tungsten compound is used.
It is preferred to add 5 moles of Lewis base or chelating agent. Such additives include acetylacetone,
Acetoacetic acid alkyl esters, tetrahydrofuran,
Examples thereof include benzonitrile. When a polar monomer is used, it may be a Lewis base itself as described above, and it may have its action even if the above compound is not added. Thus, the monomer solution containing the catalyst component (Solution A) has substantially sufficient stability.

On the other hand, the activator component in the metathesis polymerization catalyst system is an organometallic compound centered on a metal alkylated compound of Group I to III of the periodic table, particularly tetraalkyltin,
Alkyl aluminum compounds, alkyl aluminum halide compounds are preferable, specifically, diethyl aluminum chloride, diethyl aluminum chloride, trioctyl aluminum, dioctyl aluminum iodide,
Tetrabutyltin etc. can be mentioned. By dissolving the organometallic compound as the activator component in the monomer, the other solution (corresponding to the solution B) is formed.

In the present invention, a molded article can be obtained basically by mixing the solution A and the solution B, but with the above composition as it is, the polymerization reaction is initiated very quickly, so that the molded article is molded. Curing may occur before it is sufficiently poured into the mold, and therefore it is preferable to use an activity modifier.

As such a regulator, Lewis bases are generally used. Among them, ethers, esters,
Nitriles and the like are used. Specific examples thereof include ethyl benzoate, butyl ether, diglyme and the like. Such a regulator is generally used by adding it to the solution side of the component of the activator of the organometallic compound. When a monomer having a Lewis base is used as described above, it can also serve as a regulator.

The amount of the metathesis polymerization catalyst system used is, for example, when a tungsten compound is used as the catalyst component, the ratio of the tungsten compound to the raw material monomer is about 1000: 1 to 15000: 1, preferably 2: 1.
It is around 000: 1, and when an alkylaluminum is used as the activator component, the ratio of the aluminum compound to the raw material monomer is about 10 on a molar basis.
0 to 1 to 2000 to 1, preferably about 200 to 1 to 50
A neighborhood of 0 to 1 is used. Further, as described above, the masking agent and the adjusting agent can be appropriately adjusted and used depending on the amount of the catalyst system used by experiments.

The molded product obtained according to the present invention may further contain various additives in order to improve or maintain its properties in practical use. Such additives include fillers, pigments, antioxidants, light stabilizers, flame retardants, polymer modifiers and the like. Such additives cannot be added after the crosslinked polymer of the present invention has been molded, and therefore, when added, it is necessary to add them to the above-mentioned raw material solution in advance.

The easiest method is the solution A described above.
And a solution B may be added in advance to either or both of them, but in that case, they do not react to a certain extent with the catalyst component and activator component having strong reactivity in the liquid and do not react to some extent. Moreover, it must be one that does not inhibit polymerization. If the reaction does not substantially inhibit the polymerization even when the reaction is unavoidable, it is possible to prepare a third liquid by mixing with the monomer and mix and use it immediately before the polymerization. A method in which the polymerization catalyst or activator is used as the third liquid and the above additives are added to solution A or solution B not containing the third liquid is also considered. Furthermore,
In the case of a solid filler, when the two components are mixed and the shape is such that the voids can be sufficiently filled immediately before starting the polymerization reaction or during the polymerization, it is filled in the mold. It is also possible. Reinforcing agents or fillers as additives are effective in improving the bending modulus. Examples of such a material include glass fiber, mica, carbon black, and wollastonite. Those obtained by surface-treating these with a so-called silane coupler can also be suitably used.

The molded product obtained by the present invention is
It is preferable to add an antioxidant, and therefore,
It is desirable to add a phenol type or amine type antioxidant to the solution in advance. Specific examples of these antioxidants include 2,6-t-butyl-p-cresol, N,
Examples thereof include N'-diphenyl-p-phenylenediamine and tetrakis [methylene (3,5-di-t-butyl-4-hydroxycinnamate)] methane.

The molded product obtained according to the present invention may have another polymer added thereto in the state of a monomer solution. As such a polymer additive, the addition of an elastomer is effective in enhancing the impact resistance of the molded product and controlling the viscosity of the solution. Elastomers used for such purpose include styrene-butadiene-styrene triblock rubber, styrene-isoprene-styrene triblock rubber, polybutadiene, polyisoprene, butyl rubber, ethylene propylene-diene terpolymer,
A wide range of elastomers such as nitrile rubber can be mentioned.

In the first-stage molding according to the present invention, once the polymerization reaction is started in the mold, the temperature of the monomer is rapidly increased by the reaction heat, and the polymerization reaction is completed in a short time. This temperature rise reaches the glass transition temperature or higher of the obtained molded product, and at this point the molded product is still soft when taken out. In normal molding, the molded product is further held in the mold, and even if the molded product is taken out, the mold cavity is opened and the molded product is opened after a low temperature state in which the mold cavity is not deformed. That is, in the prior art, there was no idea that a molded product was taken out while it was soft at high temperature because of deformation. In the present invention, the molded product is taken out into a soft place at a high temperature, which has not been considered in the prior art, and the second stage is molded and cooled in a very inexpensive shaping mold.

According to the present invention, the first stage is 3 to 5 kg /
The relatively expensive mold capable of withstanding a pressure of about cm ² is mainly for obtaining a flat plate-shaped molded product, not for obtaining the final shape, and thus can be commonly used. Further, the pressure resistance of the second-stage type is almost unnecessary, and for example, wooden can be sufficiently used and can be manufactured at an extremely low cost. Therefore, it is extremely advantageous in industrial production that a mold, which must be prepared in large numbers in order to obtain molded products having various shapes according to various uses, can be manufactured at an extremely low cost.

When carrying out the two-step molding method of the present invention, the temperature of the molded product obtained by the first-step molding is an important factor when moving to the second-step molding. That is, the surface temperature of the molded product (glass transition temperature of the molded product) at this time is -40 ° C or higher,
Control below + 30 ° C. If this temperature is too high, the molded product becomes too soft, and it becomes difficult to remove it from the first-stage molding die and move it to the second-stage molding die. On the other hand, if the temperature is too low, the molded product becomes too hard and does not bend, and the shaping in the second stage molding cannot be sufficiently performed.

[0026]

According to the present invention, it is possible to inexpensively and easily obtain a molded article having a curved surface according to the purpose by using one common mold.

Further, the molded product of the present invention is smooth on both the front and back surfaces, has excellent aesthetic properties, and is lightweight with no residual distortion. Therefore, it can be used in a wide range of applications, mainly for large-scale products such as exterior members of various devices. Can be used. Among them, in particular, since it has excellent concrete resistance and good mold releasability from the concrete after hardening, the molded product advantageously obtained by the molding method of the present invention may have a curved surface, and thus it is used as a control panel. Can be recommended.

[0028]

EXAMPLES The present invention will be described below with reference to examples. It should be noted that the embodiments are for explanation, and the present invention is not limited thereto.

[0029]

[Example 1] Cavity size, width 500 mm, length 50
A mold having a film gate of 0 mm, a depth of 10 mm and a length of 500 mm and having a surface made of chrome-plated steel and capable of heating was used for the first stage molding. At the time of molding, a flat plate-shaped spacer having a thickness of 4 mm was placed in the mold cavity, and the inner depth of the cavity dimension was set to 6 mm.

The shaping cooling mold for the second stage molding has a width of 500.
A veneer plate having a size of mm, a length of 500 mm and a thickness of 5 mm was bent in the width direction to a diameter of 250 mm to obtain a shape having a chamfered curved surface, which was reinforced by a wooden board so as not to be deformed. I made a corresponding female mold in the same way.

(Monomer solution) A solution of T02 manufactured by Teijin Hercules Co., Ltd. containing mainly dicyclopentadiene, an elastomer, trioctylaluminum and dioctylaluminum iodide was used as a solution A.
Further, a solution B of T02 manufactured by Teijin Hercules Co., Ltd. containing mainly dicyclopentadiene, an elastomer and tungsten hexachloride was used as a solution B.

(Molding) The steel mold for the first-stage molding is heated to 90 ° C. for the cavity mold and 70 ° C. for the core mold, and after closing the mold, a solution is mixed therein with a mixing head using an ordinary RIM molding machine. A and solution B were collision-mixed and injected.

Thirty seconds after filling the liquid, the mold was opened, the molded product was taken out, immediately placed on the male mold of the second-stage molding wooden mold that had been left at room temperature, and the female mold was put on the male mold to manually After pressing with, the four corners were fastened with bolts and nuts. The temperature of the surface of the molded product when placed on the male mold was 153 ° C.

After 30 minutes, the mold was opened and the molded product was taken out. As a result, it had a curved surface with a diameter of 250 mm. The glass transition temperature of this molded product was 135 ° C. as measured by the DMA method.

[0035]

[Comparative Example 1] Example 1 except that the mold was opened and the molded product was taken out 15 seconds after the first-stage molding steel mold was liquid-filled.
Molding was performed under the same conditions as above. The molded product taken out of the steel mold was too soft to be mounted well on the male mold of the second-stage wooden mold. At this time, the surface temperature of the molded product was 175 ° C.

[0036]

[Comparative Example 2] A molded product was placed on the male mold of the first-stage molding steel mold and the second-stage molding wooden mold, and the surface temperature was 90 ° C.
After that, molding was performed under the same conditions as in Example 1 except that the female mold was covered and left for 30 minutes. After that, the molded product obtained by opening the mold was only deformed from the horizontal surface to the curved surface of 40 mm.

[0037]

[Example 2] The same method as in Example 1 was carried out except that the following conditions were changed to obtain a molded product having a curved surface with a diameter of 250 mm.

That is, the spacer of the steel mold for the first stage molding was removed, the cavity size was set to 10 mm in depth, and this mold was opened 40 seconds after liquid filling.

The surface temperature when the molded product was placed on the male mold of the second-stage molding wooden mold was 119 ° C. The glass transition temperature of the obtained molded product was 137 ° C. measured by DMA method.
Met.

[0040]

Example 3 The same method as in Example 1 was carried out except that the following conditions were changed to carry out molding to obtain a molded product having a curved surface with a diameter of 250 mm.

That is, a flat plate-shaped spacer having a thickness of 7 mm was placed in the first-stage steel mold cavity for molding,
The inner depth of the cavity was 3 mm. Further, this mold was opened 20 seconds after the liquid filling.

The surface temperature when the molded product was placed on the male mold of the second-stage molding wooden mold was 160 ° C. The glass transition temperature of the obtained molded product is 132 ° C. as measured by the DMA method.
Met.

[0043]

[Example 4] The inner surface of the cavity was set to 8 mm, and the mold opening time after liquid filling and the time until the molded product was pressed by the female mold of the second-stage wooden mold were adjusted to adjust the surface of the molded product. Molding was performed in the same manner as in Example 2 except that the temperature was changed variously.
At this time, finally, the degree of bending of the obtained molded product was measured.

The relationship between the two is shown in FIG.

[Brief description of drawings]

FIG. 1 shows the relationship between the surface temperature (° C.) of a molded article and the diameter of the curved surface of the molded article obtained in Example 4.

Claims (1)

[Claims] 1. A monomer liquid comprising a metathesis-polymerizable cyclic olefin containing a catalyst component of a metathesis polymerization catalyst system (solution B) and a monomer liquid comprising a metathesis-polymerizable cyclic olefin containing an activator component of a metathesis polymerization catalyst system. The surface temperature T (° C.) of the crosslinked polymer molding obtained by mixing (solution A) and injecting it into a mold and performing polymerization is Tg-40 ≦ T ≦ Tg + 35 [where Tg is the crosslinked polymer Indicates the glass transition temperature (° C) of a molded product. ], The crosslinked polymer molded product is transferred from the inside of the mold to a shaping mold having a curved surface and subjected to shaping cooling, and a method for producing a crosslinked polymer molded product having a curved surface.