JPH0641508B2 - Method for producing crosslinked polymer molded product and raw material for molding material - Google Patents

Description

TECHNICAL FIELD The present invention relates to a method for producing a novel polymer molded product having an improved cyclopentadiene-based polymer, and a molding material raw material therefor. More specifically, it relates to a method for producing a crosslinked polymer molded article by bulk-polymerizing a monomer containing dicyclopentadiene using a metathesis polymerization catalyst, and a molding material raw material therefor.

[Prior Art] Dicyclopentadiene (hereinafter sometimes abbreviated as "DCP") is a thermodynamically-determined cyclopentadiene that is one of the main components of the C ₅ fraction when ethylene or the like is produced by naphtha cracking. It is obtained as a stable dimer and can be said to be a rich petrochemical raw material.

Conventionally, DCP has been used as a raw material for obtaining petroleum resins and the like by thermal radical polymerization or cationic polymerization. However, recently, a technique has been developed in which two polymerized bonds in the ring of DCP are subjected to ring-opening polymerization by an olefin metathesis polymerization catalyst system to obtain a crosslinked polymer compact from DCP at once (for example, JP-A-58-129013). See the bulletin). This technology is that a large-sized molded product can be easily obtained from the above-mentioned rich petrochemical raw materials by the reaction molding method, and the molded product has excellent physical properties with a good balance of rigidity and impact resistance. Is industrially valuable in that

By the way, the metathesis catalyst system used in the above reaction molding method is generally activated as a catalyst system by a combination of a transition metal salt catalyst such as tungsten, rhenium or tantalum and an organometallic compound such as aluminum or tin for activating it. Expressed. The above method takes advantage of this point, and the polymerization is not started in a state where both the catalyst component and the activator component are mixed in the DCPs separately separated, but by rapidly mixing the two, the metathesis Polymerization is disclosed, and it is devised so that reaction molding proceeds and molded articles are obtained all at once.

Such a metathesis catalyst system is very reactive with both of the above components, not only easily reacts with oxygen and water, but also easily reacts with other polar components in the monomer, and has a catalytic ability. Is known to deactivate. Therefore, DCP used as a monomer in such a reaction molding method
Is required to be free of impurities that inhibit such a metathesis catalyst system, and it is extremely difficult to selectively remove only such catalysts. Therefore, DCP having a high degree of purification is generally used. To be By the way, D
As the degree of purification of CP increases, the freezing point rises above 33 ° C. Although the freezing point is lowered to some extent by dissolving the catalyst system components as the reaction liquid for polymerization for reaction molding, it is often the case that the freezing point of 20 ° C. or higher is generally reached as the liquid, and the reaction liquid becomes slightly lower at room temperature. It has been found that there is a problem in that it freezes and cannot be used as it is as a liquid reaction solution.

On the other hand, in the polymerization reaction liquid, each component is very active even when the catalyst system component is divided into two liquids, and it is found that the activity decreases in a relatively short time at a temperature of 30 ° C. or higher. It has also been found that it is difficult to keep the polymerization reaction solution warm and keep it in a liquid state so that it can be used immediately. That is, it turned out that there is a very troublesome problem that the reaction solution for reaction molding must be purposely dissolved by heating while preparing the solution and immediately before use. did.

As a countermeasure, in order to cause a freezing point depression in DCP, it is possible to add a component that does not inhibit the activity of the catalyst system, but the component does not polymerize, and as a low molecular component,
When it remains in the crosslinked polymer molded product, it may impair the properties of the polymer molded product, may be easily ignited, and may cause various inconveniences.

[Problems to be Solved by the Invention] Therefore, the present inventor is capable of causing a freezing point effect by being mixed with DCP which is a liquid at room temperature, has metathesis polymerizability, and is compatible with DCP. We have conducted intensive research to find compounds that can be polymerized.

Furthermore, in the case of the metathesis polymerization of DCP described above, the polymerizability is such that it can be practically used, but depending on the conditions, the monomer may remain and it may have a peculiar odor. It is desirable that the above-mentioned compound for copolymerization has stronger polymerizability. In addition to the above requirements, the present inventor has conducted earnest research to find a compound for copolymerization with DCP that can also satisfy this requirement.

[Means for Solving the Problems] That is, the present inventor may sometimes abbreviate to 5-alkylidenebicyclo [2.2.1] hept-2-ene (hereinafter referred to as “ABH”) represented by the following general formula [I]. ) Was focused on.

[In the formula, R ₁ and R ₂ represent a hydrogen atom or an alkyl group having 3 or less carbon atoms, but R ₁ and R ₂ are not hydrogen atoms at the same time. The compound represented by the general formula [I] has a 5-alkylidene-norbornene ring having a strain larger than that of a normal norbornene ring, and is expected to have strong metathesis polymerizability. However, on the other hand, it has an acyclic olefin group, and when it participates in the metathesis reaction, it acts as a terminal terminating agent, and there is a risk that a sufficiently high polymer is obtained.

However, when the present inventors actually carried out the metathesis polymerization, it is considered that the acyclic olefin group is involved in the metathesis reaction, although it is considered that the acyclic olefin group is substituted by at least three alkyl groups. Moreover, it was found that the norbornene ring exhibited strong polymerizability as expected, and the present invention was achieved. Furthermore, the ABHs are cyclopentadiene and conjugated chain diene,
For example, butadiene and Diels Alde
r) It can be easily obtained by the isomerization reaction of 5-alkenylnorbornene produced by the reaction, and some of them are industrially produced and easily available.

Further, the obtained copolymer not only has a performance comparable to that of the DCP homopolymer, but the portion of the ABH chain is a chain having almost no crosslinkage and has a non-reactive property. It has also been found that, because it has a cyclic olefin, it has the possibility of exhibiting superior performance depending on the method of use.

The present invention has been achieved based on the above facts, (1) in the presence of a metathesis polymerization catalyst system cycloalkenes, as a raw material monomer in the method of polymerizing to obtain a crosslinked polymer molded article, Dicyclopentadiene 99-50 mol%
And 5-alkylidene bicyclo [2.2.1] hept-2-
Another aspect of the present invention is a method for producing a crosslinked polymer molded article, which comprises using a monomer mixture consisting essentially of 1 to 50 mol% of ene. A reactive solution of a cyclic olefin compound (solution A) containing at least one compound having two cyclic olefin groups in one molecule containing a metathesis polymerization catalyst system catalyst, b. Containing a metathesis polymerization catalyst system activator A reactive solution of a cyclic olefin compound containing at least one compound having two cyclic olefin groups in one molecule (solution B), which is a combination of at least reactive solutions, wherein the solution A and the solution B are cyclic. The composition of both olefin compounds is 99-50 mol% dicyclopentadiene and 5-
Alkylidene bicyclo [2.2.1] hept-2-ene 1-5
It is a raw material for a molding material, which is a monomer mixture substantially consisting of 0 mol%.

The DCP used in the present invention is preferably highly purified as described above. DCP is generally obtained by separating and purifying from a C ₅ fraction by-produced by naphtha cracking. More specifically, the separated C ₅ fraction is heat-treated to dimerize cyclopentadiene to cause a difference in boiling point from other C ₅ fractions, and the method is generally purified by distillation. However, by this method alone, dienes having 4 to 6 carbon atoms other than cyclopentadiene, such as butadiene, isoprene, piperylene, etc. and cyclopentadiene Diels
Diels Alder reaction adduct such as isopropenyl norbornene is produced as a by-product, and since these have little boiling point difference with DCP, they cannot be mixed. The resulting DCP is dissociated into monomers by heating, and the difference in the dissociation reaction rate of adducts at that time is used to preferentially recover cyclopentadiene, further redimerization, and purification. Things are also done.

The DCP used in the present invention generally has a DCP purity of 95%.
As a matter of course, it is preferable that the content is 97% or more, and the impurities do not inhibit the activity of the metathesis catalyst system, but it is preferable that the impurities have metathesis polymerizability. The content of polar compounds such as alcohols, carboxylic acids, and carbonyl compounds that inhibit metathesis polymerization is preferably as low as possible.

The ABHs used in the present invention are preferably those similarly purified. ABHs include 5-ethylidenebicyclo [2.2.1] hept-2-ene (ENB) and 5-isopropylidenebicyclo [2.2.1] hept-2-ene (PN).
B) is preferable, and ENB is particularly preferable.

As the raw material monomer used in the present invention, as described above, D
A mixture containing CP and ABH as a main component is used, but a metathesis-polymerizable monomer other than the above may be added and used as the third component. The third component monomer may generally be present in a small amount as a contaminant in DCP or ABH, but it is generally DCP and ABH as long as the characteristics of the present invention are not impaired in the crosslinked polymer of the present invention. The mixture can be used by copolymerizing preferably in an amount not exceeding 20 mol% with respect to the mixture, and a cross-linked polymer obtained by copolymerizing the third component monomer is also produced by the present invention.

Examples of the third component include cyclopentadiene-methycyclopentadiene / codimer, norbornene, dihydrodicyclopentadiene, 5-phenylnorbornene, 5-
Hydrocarbon-based cycloalkenes such as isobutylnorbornene, 5-cyanonorbornene, 5-methyl-methoxycarbonylnorbornene, cycloalkenes containing different elements such as N-hexylnadic acid imide dibromophenylnorbornene can be given.

In the present invention, the ratio of DCP and ABH used is 99: 1.
Although a range of up to 50:50 (mol%) is used. ABH is preferably 3 to 10 mol% for the purpose of mainly lowering the melting point of DCP, and when it is intended to use the properties of ABH such as increasing the polymerization rate, the range of ABH is 20 to 45 mol% is preferable. Even if ABH is copolymerized to a considerable extent, the thermal properties, such as the second-order transition point, are not greatly impaired, and if post-reactivity is used, it can be improved rather depending on the treatment method. is there.

As is generally known, the metathesis polymerization catalyst system comprises a two-component system consisting of a main catalyst component and an activator component. Therefore, the activator component is first added to the monomer mixture, then the main catalyst component is added, the polymerization is initiated, and the mixture is shaped until it loses fluidity to obtain a crosslinked molded product, or the main catalyst is added to the monomer mixture. A component and an activator component may be added simultaneously to obtain a crosslinked product in the same manner. However, the metathesis polymerization reaction is generally an exothermic reaction, and once the polymerization is started, the system is further heated to accelerate the reaction and complete the reaction at a very high speed. With such a method, it is often difficult to shape before losing fluidity.

Therefore, as described above, together with the monomer mixture, two solutions, that is, a solution containing the main catalyst component of the metathesis catalyst system (solution A) and a solution containing the activator component (solution B) are prepared in advance and subjected to collision mixing. (RIM method), a static mixer, or the like, rapid mixing, immediate injection into a mold, shaping, and curing in the mold to obtain a molded product can be suitably applied. In that case, the composition of the monomer mixture does not necessarily need to be the same in both liquids, and can be arbitrarily changed. In particular, when attempting to utilize the melting point lowering, in general, when the activator solution (solution A) uses a monomer having the same composition, the freezing point may be higher than that of the catalyst solution (solution B). Since the amount is large, it is possible to adopt a method in which the mixing ratio of ABH is increased in this solution.

Such a method for producing a molded product by a two-liquid mixing method of monomers mainly containing DCP is basically disclosed in, for example, Japanese Patent Laid-Open No. 58-129013.

Salts such as halides of tungsten, rhenium, tantalum, etc. are used as the catalyst component in the metathesis polymerization catalyst system in the above-mentioned molding method, but tungsten compounds are particularly preferable. As such a tungsten compound, tungsten halide, tungsten oxyhalide and the like are preferable, and more specifically, tungsten hexachloride, tungsten oxychloride and the like are preferable. It has been found that when such a tungsten compound is directly added to the monomer, it immediately starts cationic polymerization, which is not preferable. Therefore, it is preferable that such a tungsten compound is previously suspended in an inert solvent such as benzene, toluene, chlorobenzene and the like, and a small amount of an alcohol compound or a phenol compound is added thereto to be solubilized and used.

Further, as described above, in order to prevent undesired polymerization, it is preferable to add about 1 to 5 mol of Lewis base or chelating agent to 1 mol of the tungsten compound. Examples of such additives include acetylacetone, acetoacetic acid alkyl esters, tetrahydrofuran, benzonitrile and the like. By doing so, a DCP solution containing tungsten compound (solution A
(Corresponding to) will have sufficient stability in practical use.

On the other hand, the activator component in the metathesis polymerization catalyst system is preferably an organometallic compound centered on an alkylated compound of a metal of Group I to Group III of the Periodic Table, particularly tetraalkyltin, an alkylaluminum compound, an alkylaluminum halide compound, Specific examples thereof include diethyl aluminum chloride, diethyl aluminum chloride, trioctyl aluminum, tetrabutyl tin, and the like. By dissolving the organometallic compound as the activator component in DCP or the DCP-containing mixed monomer, the other solution (corresponding to solution B) is formed.

In the present invention, basically, a crosslinked polymer molded product can be obtained by mixing the solution A and the solution B, but the polymerization reaction may start very quickly depending on the temperature of the mold. Therefore, curing may occur before it is sufficiently poured into the molding mold, and therefore an activity modifier can be used.

As such a regulator, Lewis bases are generally used, and ethers, esters, nitriles and the like are used. Specific examples thereof include ethyl benzoate, isopropyl ether, 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.

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 DCP mixed monomer is about 1000: 1 to about 15000, preferably 2000: 1. When the alkylaluminum is used as the activator component, the ratio of the aluminum compound to the DCP mixed monomer is about 100: 1 to about 2 on a molar basis.
Around 000 to 1, preferably about 200 to 1 to about 500 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.

Various additives may be added to the crosslinked polymer molded product according to the present invention in order to improve or maintain its properties in practical use. Such additives include fillers, pigments, antioxidants, light stabilizers, 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 simplest method is to add it to either or both of the solution A and the solution B in advance. In that case, a catalyst component having a strong reactivity in the solution or activation It must be a substance that does not react with the components of the agent for practical purposes and does not hinder the polymerization. In any case, if the reaction is unavoidable but coexistence does not substantially inhibit the polymerization, it can be mixed with the monomer to prepare the third liquid, and mixed and used immediately before the polymerization. . Further, in the case of a solid filler, both components are mixed, and immediately before the initiation of the polymerization reaction or during the polymerization, those having a shape capable of sufficiently filling the voids, in the molding mold, It is also possible to fill it.

Reinforcing agents or fillers as additives are effective in improving the bending modulus. Examples thereof include glass fiber, mica, carbon black, wollastonite and the like. Those obtained by surface-treating these with a so-called silane coupler can also be suitably used.

In addition, it is preferable to add an antioxidant to the crosslinked polymer molded product of the present invention. Therefore, it is desirable to add a phenol-based or amine-based antioxidant to the solution in advance. Specific examples of these antioxidants include 2,6-t
-Butyl-P-cresol, N, N'-diphenyl-P
-Phenylenediamine, tetrakis [methylene (3,5-di-t-butyl-4-hydroxycinnamate)], methanemethylene-4,4'-bis (3,5-di-t-butylphenol), etc. .

Further, in the polymer molded product of the present invention, another polymer may be added 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. Examples of elastomers used for such purpose include a wide range of elastomers such as styrene-butadiene-styrene triblock rubber, styrene-isoprene-styrene triblock rubber, polybutadiene, polyisoprene, butyl rubber, ethylene propylene-diene terpolymer.

As described above, the polymer molded product of the present invention is produced by simultaneously performing polymerization and molding. Therefore, it is preferably manufactured by the so-called RIM method. In the RIM molding, as described above, the monomer solution in which the catalyst component and the activator component are separately dissolved (that is, the solution A and the solution B) is rapidly mixed in the mixing head portion of the RIM machine to form the mold. A general method is to obtain a molded product by injecting the mixture into the inside and polymerizing and molding it.

The injection pressure into the mold can be relatively low, so it is possible to use inexpensive molds.

The injection pressure to the mold can be used at a relatively low pressure, and therefore, it is possible to use an inexpensive mold. Further, when the polymerization reaction in the mold starts, the temperature in the mold rapidly rises due to the reaction heat, and the polymerization reaction ends in a short time.
Unlike the case of polyurethane-RIM, it is easy to release from the mold, and a special release agent is often unnecessary.

The surface of the molded product is polar, probably because an oxide layer is formed on the surface of the molded product, and it has good adhesion to commonly used paints such as epoxy and polyurethane.

[Advantages of the Invention] As described above, the polymer molded product according to the present invention has improved workability in terms of the melting point of the liquid, the polymerizability, etc., as compared with the case of the DCP homopolymer. Various molded products can be advantageously produced. Further, it is possible to raise the softening point by post-treatment or the like by utilizing the reactivity of the chain-like unsaturated bond remaining in the system. Therefore, it can be said that it is a combination of a method for producing an improved crosslinked polymer molded article and a molding material raw material which are extremely industrially advantageous.

The molded product thus obtained can be used in a wide range of applications, centering on large molded products such as members of various transportation equipment including automobiles, housings of electric and electronic devices.

[Examples] The present invention is described in detail below with reference to Examples. It should be noted that the embodiment is for the purpose of explanation, and the present invention is not limited to this.

Examples 1 to 7 and Comparative Example 1 Commercially available dicyclopentadiene was purified by distillation in a nitrogen stream under reduced pressure to obtain purified dicyclopentadiene having a freezing point of 33.4 ° C. 99 for purity measurement by gas chromatography
The purity is over%. Meanwhile, commercially available 5-ethylidene bicyclo [2.2.1] hept-2-ene was similarly distilled,
A purity of 98.5% or more was obtained by the purity measurement by gas chromatography.

In order to examine the melting point lowering effect of 5-ethylidene bicyclo [2.2.1] hept-2-ene (ENB), mixed monomer liquids in which ENB was replaced with 2.5 mol%, 5 mol% and 10 mol% of DCP respectively It was found that the freezing point was lowered in proportion to the addition amount as shown in the table below.

[Preparation of catalyst component solution] 20 g of tungsten hexachloride was added to 70 ml of toluene under a nitrogen stream, and then a solution of 21 g of nonylphenol and 16 ml of toluene was added to prepare a 0.5 M tungsten-containing catalyst solution. On the other hand, nitrogen gas was purged overnight to remove hydrogen chloride gas purified by the reaction between tungsten hexachloride and nonylphenol to obtain a polymerization catalyst.

10 ml of this solution, 1.0 ml of acetylacetone mixed monomer 500
ml was mixed to prepare a solution A having a tungsten content of 0.01M.

[Preparation of Activator Component Solution] Diethyl aluminum chloride 1.8 g and isopropyl ether 3.75 ml mixed monomer 500 ml were mixed to prepare a 0.03 M solution B as an aluminum content.

When the prepared solution was kept at 25 ° C, the solution prepared only from pure dicyclopentadiene was an activator component solution,
Both the catalyst component solutions were frozen, but all of the mixed monomer solutions remained in solution.

The mixed monomer solution of Example 3 was stored in a refrigerator having an internal temperature of 7 ° C., but neither solution was frozen. The effect of lowering the freezing point is shown, and it can be seen that it is very easy to use in practical use.

Further, using a mixed monomer having an ENB content of 20 mol% (Example 4), 30 mol% (Example 5), 40 mol% (Example 6), and 48 mol% (Example 7), solution A and solution B was prepared.

The above solution was taken out into a syringe in which 10 ml of the catalyst component solution (solution A) and 10 ml of the activator component solution (solution B) were kept at an internal temperature of 25 ° C. and sufficiently replaced with nitrogen. Such a syringe was extruded at a constant speed, a liquid was injected, and the mixture was put into a microminiature RIM machine capable of being mixed in a nozzle and poured into a mold to obtain a plate-like extremely strong three-dimensional polymer molded product.

The time when the exothermic heat in the system is suddenly started after mixing the solutions and the maximum temperature reached in the system are indexes for judging whether the polymerization is carried out without being hindered.
As the proportion of B increases, the onset time tends to be shorter and the maximum temperature reached tends to be higher, which indicates that ENB has a high metathesis polymerizability.

Although it is considered that the good polymerizability was helped, the odor, which is considered to be due to the residual monomer from the molded product, was reduced, and the excellent properties of the cross-linked copolymer according to the present invention can be seen.

Further, the softening point by the TMA method, which is an index of heat resistance and chemical resistance, and the swelling ratio using toluene were measured, and the results are summarized in Tables 2 and 3. Swelling rate is pure D
It tends to increase as the copolymerization ratio of ENB increases as compared with the case of using CP, but it does not increase so much and is in a range in which there is no practical problem. On the other hand, TM
The softening point by A is almost the same (some cases are large and some are small) as compared with the case where pure DCP is used,
Also, when the softening point of the sample heated to 280 ° C. is measured again, the values are slightly higher, but the apparent softening point is no longer observed as in Example 5, and the softening point is improved by the post-treatment using the ENB component. It shows the possibility of.

Claims (2)

[Claims] 1. A method for polymerizing cycloalkenes in the presence of a metathesis polymerization catalyst system to obtain a crosslinked polymer molding, wherein dicyclopentadiene 99 to 50 is used as a raw material monomer.
A process for producing a crosslinked polymer molding, which comprises using a monomer mixture consisting essentially of 1 mol% and 5-alkylidene bicyclo [2.2.1] hept-2-ene 1-50 mol%. 2. A reactive solution (solution A) of a cyclic olefin compound containing at least one compound having two cyclic olefin groups in one molecule containing a catalyst of a metathesis polymerization catalyst system, b. A metathesis polymerization catalyst. A reactive solution of a cyclic olefin compound (solution B) containing at least one compound having two cyclic olefin groups in one molecule containing an activator of the system, The cyclic olefin compounds in Solution A and Solution B have a combined composition of 99 to 50 mol% dicyclopentadiene and 5
-Alkylidene bicyclo [2.2.1] hept-2-ene 1
A raw material for a molding material, which is a monomer mixture substantially consisting of ˜50 mol%.