JPH0762064B2 - Thermosetting resin manufacturing method - Google Patents

Description

TECHNICAL FIELD The present invention relates to a method for producing a thermosetting resin by bulk polymerization of norbornene-based monomers, and more particularly to a method for producing a crosslinked thermosetting resin having a high heat distortion temperature. Regarding

BACKGROUND ART A method for ring-opening polymerization of a norbornene-based monomer such as dicyclopentadiene or methyltetracyclodecene in a mold is known.

For example, Japanese Patent Laid-Open No. 58-129013 discloses a reaction injection molding method (RI
Method M) discloses a process for preparing a thermosetting dicyclopentadiene (DCP) homopolymer using a metathesis catalyst system, and in a preferred embodiment, the homopolymer is a halogenated tungsten, oxyhalogenated tungsten. One solution consisting of a mixture of the catalytic component of such a metathesis catalyst system and a monomer (DCP), and the other solution consisting of a metathesis catalyst activator such as an alkylaluminum halide and a monomer (DCP). Combine the solutions in a reaction injection molding (RIM) machine, then
Manufactured by pouring into a mold.

JP-A-59-51911 discloses a ring-opening polymerization method in which a cyclic olefin containing a norbornene ring is bulked by a method using a metathesis catalyst system in the RIM method. For prolongation, it has been proposed to use alkoxyalkylaluminum halide or aryloxyalkylaluminum halide cocatalysts as cocatalysts (activators).

The ring-opening polymers and compositions comprising the ring-opening polymers and elastomers according to these disclosed methods have impact resistance,
It has relatively good performance in various physical properties required for engineering plastics such as high elastic modulus and heat resistance, but it cannot be said that it is still sufficient in view of the severely required performance in recent years. For example, the DCP homopolymer obtained by these methods usually has a glass transition temperature of about 90 ° C., which is slightly insufficient as a material in the field requiring heat resistance.

By the way, in this case, as the norbornene-based monomer used becomes polycyclic, that is, as the number of cyclic structural units in the monomer increases, the heat distortion temperature of the obtained polymer rises. However, high-purity polycyclic monomers are difficult to obtain, and because they are often solid, RIM
It becomes difficult to inject into the mold by the method.

In JP-A-61-179214, in order to increase the glass transition temperature (Tg) of the polymer product and improve the heat distortion temperature, a norbornene-based monomer such as DCP and, for example, trimethylolpropane-tris- (5-norbornene- 2-carboxylates) such as comonomers having two or more reactive dipolymeric bonds that are cleaved during polymerization to increase the number of crosslinks.
Disclosed is a copolymerization method with a comonomer having 4 or more rings in the monomer structure, such as 1,4,5,8-dimethano-1,4,4a, 5,8,8a-octahydronaphthalene. ing. However, these special comonomers have the drawback of being economically difficult to obtain.

Problems to be Solved by the Invention As a result of intensive studies to overcome the above problems, the inventors have obtained a mixture of a norbornene-based monomer and a specific crosslinkable monomer in a mold having a predetermined shape, It was found that a thermosetting resin composition having good reactivity and having a high glass transition point and improved heat resistance can be obtained by bulk polymerization in the presence of a metathesis catalyst system, and the present invention is based on this finding. Has been completed.

Means for Solving the Problems That is, the gist of the present invention is a method for producing a thermosetting resin by bulk polymerization of a mixture of a norbornene-based monomer and a crosslinkable monomer in a mold in the presence of a metathesis catalyst system, Of the thermosetting resin characterized by using 1,4,5,8-dimethano-1,4,4a, 4b, 5,8,8a, 9a-octahydro-9H-fluorenes as the crosslinking agent monomer It is in the manufacturing method.

Hereinafter, the components of the present invention will be described in detail.

(Norbornene-based monomer (b)) The norbornene-based monomer that can be bulk-polymerized according to the production method of the present invention is a substituted or unsubstituted norbornene, dicyclopentadiene, dihydrodicyclopentadiene, tricyclopentadiene, tetracyclopentadiene, or tetracyclopentadiene. Cyclododecene and the like, and specific examples include dicyclopentadiene, methyltetracyclododecene, 2-norbornene, 5-methyl-2-norbornene, 5,6-dimethyl-2-norbornene, 5-ethyl-
2-norbornene, 5-butyl-2-norbornene, 5
-Hexyl-2-norbornene, 5-octyl-2-norbornene, 5-dodecyl-2-norbornene and the like.

(Metathesis Catalyst System) The catalyst used in the present invention may be any metathesis catalyst system known as a catalyst for bulk polymerization of norbornene-based monomers (for example, JP-A Nos. 58-127728 and 58-12).
9013, 59-51911, 60-79035, 60-186511
No. 61-126115, etc.), but there is no particular limitation.

As the metathesis catalyst, tungsten, molybdenum,
Halides such as tantalum, oxyhalides,
Examples thereof include oxides and organic ammonium salts. Suitable examples are tungsten hexachloride, tungsten oxytetrachloride, tungsten oxide, tridodecyl ammonium tungstate, methyl tricapryl ammonium tungstate, tri (tridecyl) ammonium tungstate. , Tungsten compounds such as trioctyl ammonium tungstate: Molybdenum compounds such as molybdenum pentachloride, molybdenum oxytrichloride, tridodecyl ammonium molybdate, methyl tricapryl ammonium molybdate, tri (tridecyl) ammonium molybdate, trioctyl ammonium molybdate : There are tantalum compounds such as tantalum pentachloride. Among them, it is preferable to use a catalyst that is soluble in the norbornene-based monomer used in the reaction, and organic ammonium salts are preferred from the viewpoint. When the catalyst is a halide, the catalyst can be solubilized by pretreatment with an alcohol compound or a phenol compound. If necessary, Lewis base such as benzonitrile or tetrahydrofuran, acetylacetone,
A chelating agent such as alkyl acetoacetate can be used in combination, which can prevent premature polymerization.

Examples of the activator (cocatalyst) include alkylaluminum halides, alkoxyalkylaluminum halides, aryloxyalkylaluminum halides, organic tin compounds, and the like. Suitable examples are ethylaluminum dichloride, diethylaluminum monochloride, ethylaluminum. Sesquichloride, diethyl aluminum iodide, ethyl aluminum diiodide, propyl aluminum dichloride, propyl aluminum diiodide, isobutyl aluminum dichloride, ethyl aluminum dibromide, methyl aluminum sesqui chloride, methyl aluminum sesquibromide, tetrabutyl tin, alkyl aluminum halide and Preliminary reaction products with alcohol, etc.

Among these activators, alkoxyalkylaluminum halides and aryloxyalkylaluminum halides have an appropriate pot life at room temperature even when the catalyst components are mixed, and thus are advantageous in operation (for example,
JP-A-59-51911). In the case of alkylaluminum halide, there is a problem that polymerization will start immediately when a catalyst is mixed, but in that case, an activator and a regulator such as ethers, esters, ketones, nitriles and alcohols are used together. By doing so, the initiation of polymerization can be delayed (see, for example, JP-A Nos. 58-129013 and 61-120814).
issue). If these regulators are not used, it is necessary to give consideration to the equipment and operation so that even those with a short pot life can be used. In addition to the catalyst and activator, halogenated hydrocarbons such as chloroform, carbon tetrachloride and hexachlorocyclopentadiene may be used in combination (for example, JP-A-60-79035).

The metathesis catalyst represents 1 mol of the total amount of all monomers,
Usually, it is used in the range of about 0.01 to 50 mmol, preferably 0.1 to 10 mmol. The activator (cocatalyst) is generally 0.1 to 200 (molar ratio), preferably 2 to 2 with respect to the catalyst component.
Used in the range of 10 (molar ratio).

Both the metathesis catalyst and the activator are preferably used by dissolving them in the monomer, but they may be used by suspending or dissolving them in a small amount of solvent as long as the properties of the product are not substantially impaired.

(Crosslinkable Monomer) The crosslinkable monomer used in the present invention is 1,4,5,8-dimethano-1,4,4a, 4b, represented by the following formula (1).
5,8,8a, 9a-octahydro-9H-fluorene (hereinafter referred to as DMO
Abbreviated as F. ) Or its alkyl substitution
It is class F.

Any position of DMOF may be substituted with an alkyl group such as a methyl group or an ethyl group.

DMOFs can be easily obtained by subjecting DCPs and cyclopentadiene, which are easily available, to a Diels-Alder reaction as shown in the following formula (2) and separating from the reaction mixture by means such as distillation. Even if the DMOFs are not necessarily high in purity, they may be the distillate from the Diels-Alder reaction mixture and the crude DMOFs containing 50% by weight or more of DMOF as a main component. Good. In this reaction, 4,9,5,8-dimethano-3a, 4,4a,
5,8,8a, 9,9a-octahydro-1H-benzoindene (DMO
B) is mainly a byproduct.

The mixing ratio of this DMOF is 100% norbornene-based monomer.
It is 1 to 30 parts by weight, preferably 2 to 20 parts by weight, per part by weight. When the proportion of DMOFs used is low, the effect of raising the glass transition point is small, and when it is excessively high, the impact resistance of the polymer decreases, and it is not economical.

(Polymerization conditions) In the present invention, a polymerization method in which DMOFs of norbornene-based monone and a crosslinkable monomer are introduced into a mold having a predetermined shape, and bulk polymerization is performed in the mold in the presence of an elastomer and a metathesis catalyst system, A thermosetting resin composition is manufactured. It suffices if it is substantially bulk polymerization, and a small amount of an inert solvent may be present.

In a preferred method for producing a thermosetting resin composition, a mixture of a norbornene-based monomer and DMOFs is divided into two liquids and placed in another container, a metathesis catalyst is added to one of them, and an activator is added to the other. Prepare a stable reaction solution of the kind. In addition,
DMOFs may be added to either one of these two types of reaction solutions.

These two kinds of reaction solutions are mixed and then poured into a molding die kept at a high temperature, where ring-opening polymerization by a lump is started to obtain a thermosetting resin composition.

In the present invention, a collision mixing device conventionally known as a RIM molding device can be used for mixing two kinds of reaction solutions. In this case, the containers containing the two types of reaction solutions serve as separate flow sources. Two kinds of flow RI
The mixture is mixed instantaneously with a mixing head of an M machine, and then poured into a hot molding die, where it is immediately bulk polymerized to obtain a thermosetting resin composition.

Thus, impingement mixing devices can be used, but the invention is not limited to such mixing means. When the pot life at room temperature is as long as 1 hour, even after injection or injection into the preheated mold once or several times after the mixing of the two reaction solutions in the mixer is completed. Good (see, for example, JP-A-59-51911). In the case of this method, compared to the collision mixing device,
It has the advantage that the device can be miniaturized and can be operated at low pressure.

Further, the present invention is not limited to the case of using two kinds of reaction solutions. As those skilled in the art can easily understand,
For example, various modifications are possible such as putting the reaction solution and the additive in the third container and using it as the third flow.

The mold temperature is 50 ° C or higher, preferably 60 to 200 ° C, particularly preferably 90 to 130 ° C. Mold pressure is usually 0.1 ~ 100Kg / cm
It is within the range of ² .

The polymerization time may be appropriately selected, but is usually shorter than about 20 minutes, preferably 5 minutes or less, but may be longer than that.

The polymerization reaction components must be stored and operated under an atmosphere of an inert gas such as nitrogen gas. The molding die may or may not be sealed with an inert gas.

(Properties of Thermosetting Resin Composition) The bulk polymer composition obtained by the production method of the present invention is a thermosetting resin composition which becomes a hard solid when cooled.
The glass transition point (Tg) is 100 ° C. or higher, preferably 110 ° C. or higher, and has a high heat distortion temperature.

(Arbitrary component) The properties of the thermosetting resin of the present invention can be modified by incorporating various additives such as a filler, an antioxidant, a pigment, a colorant, and a polymer modifier.

The additives are mixed in advance with either one or both of the reaction solutions, or placed in the cavity of the mold.

Fillers include inorganic fillers such as glass, carbon black, talc, calcium carbonate and mica.

Polymer modifiers include elastomers and thermopolymerized DCP resins. For example, blending an elastomer can increase the impact strength of the thermosetting resin, and blending a thermopolymerized DCP resin can further improve the flexural modulus. The polymer modifier is usually added to the reaction solution and dissolved before use.

As the elastomer, natural rubber, polybutadiene, polyisoprene, styrene-butadiene copolymer, styrene-butadiene-styrene block copolymer, styrene-isoprene-styrene block copolymer, ethylene-
Examples include propylene-diene terpolymers, ethylene-vinyl acetate copolymers, and hydrides thereof.

When the reaction solution containing the monomer has a low viscosity by adding an elastomer or a heat-polymerized DCP resin,
The viscosity of the reaction solution can be adjusted to an appropriate value. Also, by adding these polymer modifiers, the freezing point of the monomer reaction solution can be lowered, and even if a monomer having a high freezing point is used, the monomer reaction solution does not solidify, so the operability in reaction injection molding is improved. To be done.

The blending ratio of these polymer modifiers can be appropriately determined,
With respect to 100 parts by weight of the thermosetting resin, in the case of an elastomer is usually 0.5 to 20 parts by weight, preferably 1 to 15 parts by weight,
In the case of heat-polymerized DCP resin, 0.5 to 150 parts by weight, preferably 2
0 to 50 parts by weight.

EXAMPLES The present invention will be described more specifically with reference to Examples and Reference Examples below, but the present invention is not limited to these Examples. All parts, ratios and percentages are by weight.

Reference Example 1 (Synthesis Example of DMOF) 700 g of dicyclopentadiene (DCP) having a purity of 98.5% and 500 ppm of 2,6-di-tert-butylphenol (BHT) were charged in an autoclave of 1, and nitrogen substitution was performed sufficiently, and then 190 ° C. The temperature was raised to, and the mixture was reacted for 6 hours to obtain a waxy product. The wax-like product thus obtained was further subjected to a packed column having 40 plates and a reflux ratio of 10 to obtain 72 g of distillate at 2 torr and 100 ° C.

This distillate (hereinafter referred to as crude DMOF) contained 70% DMOF. The remaining composition is 4,9,5,8-dimethano-3a,
The main component was 4,4a, 5,8,8a, 9,9a-octahydro-1H-benzoindene (DMOB).

Example 1 The crude DMOF obtained in Reference Example 1 was placed in two vessels according to the mixing ratio with DCP shown in Table 1, and in one of them, diethylaluminum chloride (DEAC) was added to the mixture in a concentration of 33 mmol, n-propanol. Was added to each to give a concentration of 4.95 mmol.

On the other hand, tri (tridecyl) ammonium molybdate was added to the mixture to a concentration of 4.0 mmol.

Both reaction solutions were mixed at a ratio of 1: 1. This mixture maintained a stable state where there was no change in viscosity at 35 ° C. for 1 hour (hereinafter referred to as pot life).

Both reaction solutions were rapidly injected into a mold heated to 90 ° C. having a space volume of 200 × 200 × 2 mm by using a gear pump and a power mixer. The injection time was about 15 seconds. Thirty seconds after the completion of injection, the reaction rapidly started with heat generation. And
The reaction was performed in the mold for a total of 3 minutes. These series of operations were carried out under a nitrogen gas atmosphere.

Table 1 shows the physical property values of the thermosetting resin composition when the mixing ratio of the crude DMOF was changed.

Example 2 A molded product was obtained in exactly the same manner as in Example 1 except that the crude DMOF content was kept constant at 5 parts and the type of norbornene-based monomer was changed. The physical properties of this molded product are shown in Table 2.

EFFECTS OF THE INVENTION According to the present invention, in the RIM method using a norbornene-based monomer such as dicyclopentadiene, by blending a specific crosslinkable monomer (DMOFs) that is easily available, a conventional polyDCP-based polymer is added. By comparison, a thermosetting resin having an excellent heat distortion temperature can be obtained, and a method for producing a thermosetting resin having excellent reactivity and excellent moldability can be provided. The thermosetting resin can be applied to various fields requiring mechanical strength such as heat resistance and flexural modulus and impact resistance.

Claims (1)

[Claims] 1. A method for producing a thermosetting resin by mass-polymerizing a mixture of a norbornene-based monomer and a crosslinkable monomer in a mold in the presence of a metathesis catalyst system, wherein 1,4, 5,8-dimethano-1,4,4a, 4b,
A method for producing a thermosetting resin, which comprises using 5,8,8a, 9a-octahydro-9H-fluorenes.