JPH05262822A - Polymerization of norbornene monomer - Google Patents

Abstract

PURPOSE:To provide a process for polymerizing a norbornene monomer in the presence of a metathesis catalyst which, when dissolved in a norbornene monomer solution, can give a stable solution which can be stored for a long time, therefore can be advantageously applied to reaction injection molding, and can give a polymer of a high Tg at high conversion. CONSTITUTION:The title process comprises polymerizing a norbornene monomer in the presence of a metathesis catalyst system essentially consisting of a metathesis catalyst and a metathesis cocatalyst. The metathesis catalyst comprises a complex of an antioxidant containing at least one aromatic ring or an ultraviolet absorber containing at least one aromatic ring with a halide of molybdenum.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for polymerizing norbornene-type monomers using a metathesis catalyst system, and more specifically, using a complex of a halide of molybdenum and a specific Lewis base as a metathesis catalyst, It relates to a method for polymerizing a norbornene-based monomer.

[0002]

2. Description of the Related Art Halides of molybdenum and tungsten, which are the main catalysts of the metathesis catalyst system, easily cause cationic polymerization of dicyclopentadiene (DCP) by themselves, so that a solution of DCPs in which the catalyst is dissolved cannot be formed. It is difficult to store for a long period of time and, in effect, reaction injection molding (RI
It is difficult to use for M).

JP-A-58-129013 and US Pat. No. 4,568,660 disclose dicyclopentadiene (DCP) with a solvent such as toluene by reacting a halide of molybdenum or tungsten with an alcohol or a phenol compound. )), And a norbornene-based monomer polymerization method using a compound to which a Lewis base or a chelating agent is added in order to suppress the cationic polymerization of DCPs as a metathesis catalyst has been proposed. Here, examples of the Lewis base include nitriles such as benzonitrile and ethers such as tetrahydrofuran. In addition, as a chelating agent, acetylacetones,
Acetoacetates, dibenzoylmethane and the like.

In the above-mentioned proposed known technique, the operation of reacting a halide of molybdenum or tungsten with a phenol to form a phenolate compound is complicated. Further, a solvent such as toluene, which has no metathesis polymerizability, a chelating agent, and a Lewis base function as a plasticizer for the polymer obtained by the metathesis polymerization, lower the glass transition temperature (Tg), and generate an odor. There are difficulties such as doing.

Further, it is desired that the polymer obtained by using the metathesis catalyst has a high Tg and a polymerization conversion rate,
Therefore, it has been proposed to use various activators in combination with the metathesis catalyst. However, the techniques proposed so far have not obtained satisfactory Tg and conversion, and higher levels of Tg and conversion are desired.

[0006]

The object of the present invention is to allow a solution of a norbornene-based monomer in which a catalyst is dissolved to be stored for a long period of time, and to advantageously apply it to reaction injection molding, and
It is to provide a method for polymerizing a norbornene-based monomer using a metathesis catalyst, which can obtain a polymer having a high level of Tg at a high conversion rate.

[0007]

Thus, according to the present invention, in a method of polymerizing a norbornene monomer using a metathesis catalyst essentially consisting of a metathesis catalyst and a metathesis cocatalyst, at least one metathesis catalyst is used. Provided is a method for polymerizing a norbornene-based monomer, which comprises using a complex of an antioxidant having one aromatic ring or an ultraviolet absorber having at least one aromatic ring and a halide of molybdenum (Mo).

The polymerization method of the present invention will be described in detail below. (Norbornene-based monomer) The norbornene-based monomer used in the present invention is a polycyclic cycloolefin having at least one norbornene group, and may or may not have a substituent.

Specific examples of preferable norbornene-based monomers include dicyclopentadiene, tetracyclododecene, methyltetracyclododecene, ethylidenetetracyclododecene, hexacycloheptadecene, methylhexacycloheptadecene, tricyclopentadiene and norbornene. Methyl norbornene, ethylidene norbornene, vinyl 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-
Examples thereof include norbornene and 5-dodecyl-2-norbornene. These norbornene-based monomers may have a polar group such as a cyano group, an ester bond, an ether bond, a pyridyl group and a halogen atom as a substituent.

The present invention is directed to norbornene, methylnorbornene, vinylnorbornene, ethylidene norbornene, dicyclopentadiene, tetracyclododecene, methyltetracyclododecene, ethylidenetetracyclododecene, hexacycloheptadecene, methylhexacycloheptadecene and tricyclopentadecene. It is particularly suitable for preparing homopolymers, copolymers and terpolymers of cyclopentadiene. Among them, dicyclopentadiene (DCP) is favored because of its easy availability. These norbornene-based monomers may be used alone or 2
It is also possible to use a mixture of two or more species.

At least one copolymerizable monomer may be used together with the norbornene-based monomer in the range of about 20% by weight or less. Specific examples of such comonomers are mono- and dicycloolefins having 4 to 12 carbon atoms, examples of which include cyclobutene, cyclopentene, cyclopentadiene, cycloheptene, cyclooctene, 1,5-cyclooctadiene, cyclodecene, cyclododecene,
Examples thereof include cyclododecadiene and cyclododecatriene.

(Metathesis Catalyst System) The metathesis catalyst system used in the present invention essentially consists of a metathesis catalyst and a metathesis cocatalyst. The main feature of the present invention is that a complex of a halide of molybdenum (Mo) with an antioxidant having at least one aromatic ring or an ultraviolet absorber having at least one aromatic ring is used as a metathesis catalyst. ..

Antioxidants having at least one aromatic ring and UV absorbers having at least one aromatic ring are
It can be appropriately selected from commercially available antioxidants known to exhibit an antioxidant action on norbornene-based polymers and commercially available ultraviolet absorbers. Generally, these are compounds having a lone pair of atoms, such as oxygen, nitrogen, sulfur, and phosphorus, in the molecule, and a compound in which the atom having the lone pair of electrons and an aromatic hydrocarbon are bonded. .. These compounds require low volatility for their intended use and generally have a molecular weight of about 150 or higher.

Specific examples of the above antioxidant and ultraviolet absorber include β-phenylethylene acetate, p- (N,
Ethyl N'-diethylaminoethylene) aminobenzoate, 3,5-di-t-butyl-4-hydroxyphenyl-3,5-di-t-butyl-4-hydroxybenzoate, n-octadecyl-3- (4 ' -Hydroxy-
3 ', 5'-di-t-butylphenol) propionate, tetraxy [methylene-3 (3,5-di-t-butyl-4-hydroxyphenyl) propionate] methane, phenylsulfate, ethyl-2-cyano- Three
Carboxylic acid ester compounds having an aromatic ring such as 3-diphenyl acrylate and methyl-2-carbomethoxy-3- (paramethoxy) acrylate; tris (nonylphenyl) phosphite, triphenylphosphite,
A phosphite compound having an aromatic ring such as diphenyldecyl phosphite; phenyl-α-naphthylamine, phenyl-β-naphthylamine, diphenylamine, triphenylamine, phenothiazine, phenylenediamine, 2-ethylhexyl-2-cyano-3- Aromatic amine compounds such as phenylcinnamate phenothiazine, 4,4'-tetramethyl-diaminodiphenylmethane; and aromatic amide compounds such as N, N'-diphenyloxamide. It should be noted that the so-called alkyl group-substituted phenol compound such as 2,6-di-t-butyl-4-hydroxytoluene (BHT) and 2,2'-methylenebis (4-methyl-6-t-butylphenol) has the object of the present invention. Is not achieved.

Examples of the halogen compound of molybdenum include molybdenum trichloride, molybdenum tetrachloride and molybdenum pentachloride, and molybdenum pentachloride is particularly preferable. To form a complex, an antioxidant or an ultraviolet absorber is added to an organic solvent solution of a halogen compound of molybdenum to form a complex, and then the solvent is removed. When the antioxidant and the ultraviolet absorber are liquid, they may be mixed directly, and when they are solid, they are preferably dissolved in an organic solvent and added. When the halogen compound of molybdenum and the antioxidant or the ultraviolet absorber form a charge transfer complex, the color of the solution obviously changes, so that the complex formation can be easily recognized.

The metathesis cocatalyst (ie activator) is selected from organoaluminum compounds, organotin compounds, organozinc compounds, organolead compounds, organosilicon compounds and the like. Examples of the organic aluminum compound include trialkylaluminum, alkylaluminum hydride, alkylaluminum halide, alkoxyalkylaluminum halide, aryloxyalkylaluminum halide and metaloxyalkylaluminum halide. The alkylaluminum halide co-catalyst starts polymerization immediately when mixed with the metathesis catalyst,
As is well known in the art, it is possible to delay the initiation of the polymerization by using a modifier selected from esters, ethers, ketones, alcohols and nitrites, in particular ethyl benzoate, butyl ether or diethylene glycol dimethyl ether.

The preferred metathesis cocatalyst is selected from alkoxyalkylaluminum halides and aryloxyalkylaluminum halides of the formula: (RO) aR ¹ bAIXc In the formula, R is selected from an alkyl group and a phenyl group, and R
¹ is selected from alkyl groups. X is halogen,
a, b and c represent the equivalent weight of each component in the cocatalyst,
The sum is 3.0. Preferred among these types of cocatalysts are alkoxyalkylaluminium chlorides, alkoxyalkylaluminium iodides, phenoxyalkylaluminium chlorides, phenoxyalkylaluminium iodides, especially propoxyethylaluminium chloride and propoxyethylaluminum sesquichloride. The alkylaluminum halide cocatalyst and alcohol can be added separately to form the final cocatalyst in the system. These cocatalysts are soluble in norbornene-based monomers, and the pot life can be adjusted by changing the amount of alcohol or phenol used for modification, that is, the amount of alkoxy or phenoxy residues. As the amount of alcohol or phenol increases, the pot life of the alkoxyalkylaluminum halide or phenoxyalkylaluminum halide cocatalyst becomes longer.

Metaloxyalkylaluminum halides of the formula: are also preferred metathesis cocatalysts. (RnMo) aR ¹ bAlXc In the formula, M is a metal selected from tin, lead and aluminum, R and R ¹ are each selected from an organic residue, especially a lower alkyl group and a phenyl group, and n is a kind of metal. 2 or 3, depending on the above, X is a halide, a, b and c represent the equivalent weight of each component in the cocatalyst, the sum of which is 3.0.

Organotin compounds are also preferred cocatalysts, and specific examples thereof include tetraalkyltin having a lower alkyl group such as tetraethyltin and tetrabutyltin, tributyltin hydride, triphenyltin hydride,
Examples thereof include trialkyltin hydride having a lower alkyl group such as trimethyltin hydride, triethyltin hydride, tripropyltin hydride, and triaryltin hydride. As the organic zinc compound, diethyl zinc, diisobutyl zinc, di-n
-Alkyl zinc such as butyl zinc, diphenyl zinc, and alkyl zinc halides such as alkyl zinc chloride. Examples of the organic lead compound include alkyl lead such as tetraethyl lead. Organosilicon compounds include alkyl silicon halides such as methyl silicon trichloride and hydrogenated triethylsilane. These cocatalysts are not sensitive to air and moisture and can be handled in air without the special precautions required with alkoxy and aryloxyalkylaluminum halides and other metathesis cocatalysts.

In addition to the metathesis catalyst and the cocatalyst, halogenated hydrocarbons such as chloroform, carbon tetrachloride and hexachlorocyclopentadiene may be used in combination (for example, JP-A-60-79035), tin tetrachloride, Halides such as silicon tetrachloride, magnesium chloride and germanium chloride may be used in combination (JP-A-63-1867).
No. 30).

The metathesis catalyst is usually used in an amount of about 0.01 to 50 mmol, preferably 0.1 to 10 mmol, relative to 1 mol of the norbornene-based monomer. The co-catalyst is usually used in the range of 0.1 to 200 (molar ratio), preferably 2 to 10 (molar ratio) with respect to the catalyst component. Both the metathesis catalyst and the cocatalyst are preferably dissolved in the monomer before use, but may be suspended or dissolved in a small amount of a solvent as long as the properties of the product are not substantially impaired.

(Polymerization Method) A typical example of the norbornene-based monomer polymerization method of the present invention is reaction injection molding (RIM).
Is a method of ring-opening polymerization of norbornene-based monomers in a mold in a lump form by a method. The RIM method may be substantially bulk polymerization, and a small amount of an inactive compound may be present. In a preferred bulk ring-opening polymerization method, a norbornene-based monomer mixture is divided into two liquids and placed in another container, a metathesis catalyst is added to one and a cocatalyst is added to the other to prepare two stable reaction stock solutions. .. These two types of reaction stock solutions are mixed and then poured into a mold of a predetermined shape,
Therefore, ring-opening polymerization by bulk is performed.

In bulk ring-opening polymerization, RIM has been conventionally used.
An impingement mixer known as a device can be used to mix the two stock solutions of the reaction. In this case, the containers containing the two types of reaction stock solutions serve as separate flow sources. The two streams are mixed instantaneously with the mixing head of the RIM machine and then injected into the hot mold,
Then, bulk polymerization is immediately carried out to obtain a molded product.

Further, after the mixing of the two kinds of reaction stock solutions in the mixer is completed, they may be injected or injected into the preheated mold several times (for example, JP-A-59-59).
51911, U.S. Pat. No. 4,426,502) or continuously. This method has the advantage that it can be downsized compared to an impingement mixing device and can be operated at low pressure, and it also has the advantage of increasing the injection speed when the amount of reinforcement such as glass fiber is large. By slowing down, it becomes possible to uniformly impregnate the reaction stock solution into the system.

The above ring-opening bulk polymerization method is not limited to the method using two kinds of reaction stock solutions. As will be readily appreciated by those skilled in the art, various modifications are possible, such as, for example, putting the monomer and the desired additive in the third container and using it as the third stream. The mold temperature is usually room temperature or higher, preferably 40 to 200 ° C. The mold clamping pressure is usually within the range of 0.1 to 100 kg / cm ² . The reaction stock solution is usually stored and operated under an atmosphere of an inert gas such as nitrogen gas, but the molding die is not necessarily sealed with the inert gas.

(Arbitrary Ingredients) As required, antioxidants other than the above-mentioned antioxidants having an aromatic ring, fillers such as milled glass, carbon black, talc, calcium carbonate and mica, pigments, colorants and foaming agents. , Flame retardant, sliding agent,
By blending various additives such as an elastomer, a dicyclopentadiene type thermopolymer resin and a hydrogenated product thereof,
The properties of the resulting polymer can be modified. The additives are usually mixed in advance in at least one reaction solution.

[0027]

EXAMPLES The present invention will be described in more detail below with reference to Examples and Comparative Examples, but the present invention is not limited to these Examples. Further, parts and% in these examples are based on weight unless otherwise specified. Polymerizability and polymer properties were evaluated according to the following methods.

Pot life (PL): The time from the start of mixing until the reaction liquid changed from a liquid state to a pudding state was measured and defined as pot life (PL). Smoking time (SMT): The time from the start of mixing to the time when a slight amount of smoke was generated from the surface of the produced resin was measured and used as the smoking time (SMT), which was used as a guide for the end of the polymerization reaction. A series of operations for measuring PL and SMT were performed in a nitrogen gas atmosphere.

Tg and conversion rate: After completion of the polymerization, the ampoule containing the polymer was cooled to room temperature, the polymer was taken out, and the glass transition temperature (Tg) and the conversion rate of the monomer were measured. The Tg was measured by a differential scanning calorimeter. Further, the conversion was measured by the residual ratio of the weight obtained by heating from room temperature to 400 ° C. with a thermobalance.

Example 1 and Comparative Example 1 A reactor containing 1000 ppm of 2,6-di-t-butyl-4-hydroxytoluene (BHT) and a purity of 99.
3% dicyclopentadiene (DCP) and purity 96.1
% Tricyclopentadiene (TCP) was mixed at a ratio of 90:10, and 100 parts of a monomer was added. Diethyl aluminum chloride (DEA) was added to the monomer.
C) was added to the mixture at a concentration of 23 mmol / liter, and n-propanol was added at a concentration of 23 mmol / liter with good stirring, and the mixture was allowed to stand overnight for a full reaction. This solution was maintained at 35 ° C., and a DCP-TCP monomer solution of the metathesis main catalyst shown in Table 1 at a concentration of 1 mol / liter was added with good stirring so that the concentration became 6 mmol / liter.

A 1 mol / liter DCP-TCP solution of the above metathesis main catalyst was prepared as follows. After molybdenum pentachloride was dissolved in chloroform, a predetermined amount of antioxidant or ultraviolet absorber was added to form a complex. Then, after chloroform is evaporated and separated, DC
P-TCP was added and dissolved to give a predetermined concentration.

As a comparative example, Table 1 shows the results of similar polymerization using a conventionally known catalyst. The known catalyst used here was prepared as follows. Tungsten hexachloride was dissolved in a nonylphenol hexane solution in an equimolar amount, and hydrogen chloride was removed overnight by a nitrogen gas flow. Then, an equimolar amount of acetylacetone was added, and hexane was further added to give a concentration of 1 mol / liter. did.

[0033]

[Table 1] From the results shown in Table 1, it is understood that the complex catalyst used in the present invention has a high Tg and a high conversion rate.

Comparative Example 2 Molybdenum pentachloride was dissolved using a conventionally known catalyst solubilizer, and the solution was added to a mixed solution of dicyclopentadiene (DCP) and tricyclopentadiene (TCP). The change was observed. These catalyst-containing mixed liquids were prepared as follows. Experiment No. 1-12: MoCl ₅ was used in the same DC as in Example 1.
It mixed with the P-TCP mixed liquid.

Experiment No. 1-13: MoCl ₅ was dissolved in a nonylphenol hexane solution in an equimolar amount, and after removing hydrogen chloride by a nitrogen gas flow overnight, an equimolar amount of acetylacetone was added. A similar DCP-TCP mixture was added. Experiment No. 1-14: 2,6-di-t-butyl-4-, in place of the antioxidant or UV absorber used in the preparation of the 1 mol / l DCP-TCP solution of the main catalyst of Example 1. As in Example 1 except that hydroxytoluene (BHT) was used, 1 mol / liter DCP of MoCl ₅ was used.
-Prepared TCP solution.

DCP of MoCl ₅ after 2 hours from preparation
The results of observing the state of the TCP mixed solution were as follows. Experiment number 1-12: A viscous, partially solid polymer was produced. Experiment number 1-13: It became a viscous liquid. Experiment number 1-14: It became a viscous liquid. It can be seen that in all the experiments, the polymerization of the monomer occurred, and it could not be used as it is for reaction injection molding (RIM).

Example 2 The same as in Example 1-1, except that silicon tetrachloride was further added to the monomer solution prepared by adding DEAC and n-propanol to the monomer so as to have a concentration of 10 mmol / liter. The experiment was performed according to the same method as that of the example. As a result, PL takes 35 seconds, SMT takes 74 seconds,
The Tg was 160 ° C. and the conversion rate was 98.0%. From these results, it can be seen that the activity is slightly improved when the activator is added.

Example 3 An experiment was conducted in the same manner as in Example 1-1, except that DEAC and n-propanol were replaced by the cocatalysts shown in Table 2 as monomers. The results are shown in Table 2.

Example 4 In Example 1-2, metathesis was used as the main catalyst and Mo was used.
The addition of a complex of Cl ₅ and tris (nonylphenyl phosphite) to a concentration of 6 mmol / l, the addition of a complex of MoCl ₅ and tris (nonylphenylphosphite) to a concentration of 3 mmol / l and tri (dodecyl) ammonium. The experiment was conducted according to the same procedure as in the example, except that the addition was changed so that the concentration of molybdate was 3 mmol / liter. As a result, PL was 45 seconds, SMT was 90 seconds, Tg of the polymer was 153 ° C,
The conversion rate was 97.1%.

[0040]

INDUSTRIAL APPLICABILITY In the method for polymerizing a norbornene-type monomer using the specified metathesis catalyst of the present invention, a solution of the norbornene-type monomer in which the catalyst is dissolved can be stored for a long period of time, and according to this polymerization method, Polymers with high levels of Tg can be obtained with high conversion.

[Table 1 continued]

[Table 2]

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Tomio Sugawara 1-2-1 Yokou, Kawasaki-ku, Kawasaki-shi, Kanagawa Inside Zeon Corporation R & D Center

Claims (1)

[Claims] 1. A method for polymerizing a norbornene-based monomer using a metathesis catalyst system consisting essentially of a metathesis catalyst and a metathesis cocatalyst, wherein the metathesis catalyst is an antioxidant having at least one aromatic ring or at least one aromatic ring. A method for polymerizing a norbornene-based monomer, which comprises using a complex of an ultraviolet absorber having two aromatic rings and a halide of molybdenum (Mo).