JPS6136762B2 - - Google Patents

Description

[Detailed description of the invention]

The present invention relates to a method for producing an acetylene polymer gel having good moldability. It is already known that acetylene polymers obtained by polymerizing acetylene using so-called Ziegler-Natsuta catalysts, which are composed of transition metal compounds and organometallic compounds, are organic semiconductor materials useful as electronic and electrical devices. . However, the acetylene polymer obtained in this way does not melt even when heated, and is easily subjected to oxidative deterioration under heating, so that the molding method used for ordinary thermoplastic resins cannot be used. Furthermore, a solvent that dissolves this acetylene high polymer has not yet been found.
Therefore, methods for producing practical molded articles of acetylene polymers have been limited to the following two methods. (a) A method of pressure molding a powdered acetylene polymer. (b) A catalyst solution prepared by dissolving a catalyst system consisting of a transition metal compound and an organometallic compound in an aromatic hydrocarbon such as toluene or an aliphatic hydrocarbon such as hexadecane and the interface near the free surface of gaseous acetylene or on a solid surface. A method for producing membranous and fibrous acetylene polymers by polymerizing on the surface coated with this catalyst solution (Japanese Patent Publication No. 1973-
No. 32581). However, with the former method (a), only a molded product with low mechanical strength can be obtained, and with the latter method (b), not only the shape is limited to membrane-like and fibrous-like shapes, but also the thickness is limited, and essentially only thin-walled membrane-like and fibrous molded products can be obtained. Therefore, in recent years, ^a new method for producing acetylene polymers that does not have these problems has been studied, and acetylene ^is
cyclopentadienyl)−tris(η−
cyclopentadienyl) dititanium (Ti−Ti)
It was proposed that a gel-like acetylene high polymer could be obtained by polymerizing using a catalyst [(C ₅ H ₄ )(C ₅ H ₅ ) ₃ Ti ₂ ] and hexane as a solvent [S・L・Hsu
et al., J. Chem. Phys., 69(1), 106-111.
(1978)]. However, since this method uses a very special catalyst, the ratio of catalyst cost to production cost is disadvantageous when industrially producing acetylene polymer gel. In view of the above points, the present inventors conducted various studies on a method for producing a gel-like acetylene polymer with good moldability without using a special catalyst, and as a result, they arrived at the present invention. That is, the present invention provides a method for producing an acetylene polymer by polymerizing acetylene using a catalyst system containing a transition metal compound and an organometallic compound as main components.
The catalyst system is added to a polymerization solvent in which acetylene is dissolved in advance, or the acetylene is dissolved in a polymerization solvent containing one of the catalyst components of the catalyst system. The present invention relates to a method for producing a gel-like product of an acetylene polymer, which is characterized in that the polymerization is carried out by adding other catalyst components. The gel-like material referred to in the present invention is a material in which fibrous microcrystals (fibrils) of acetylene high polymer are entangled,
It is in a state swollen in a solvent, and is essentially different from a normal crosslinked gel. According to the method of the present invention, a gel-like product of acetylene polymer can be easily obtained using a catalyst system already widely used in the industry. It is extremely useful industrially because uniform molded products of any shape and wall thickness with excellent mechanical strength can be easily produced. The present invention will be explained in detail below. The transition metal compounds used in the present invention include titanium, vanadine, chromium, iron, cobalt,
Tungsten and molybdenum metal halogen atoms or alkyl groups, alkenyl groups, aryl groups, aralkyl groups, alkoxide groups, phenoxide groups, carboxylic acid residues, cyclopentadienyl groups, acetylacetone with at most 20 carbon atoms residue, a compound having carbon monoxide (carbonyl group), and a complex of this compound with an electron-donating compound such as pyridine, triphenylphosphine, and dipyridyl. Among transition metal compounds, titanium, vanadine,
Compounds of iron, chromium and cobalt are preferred;
Particularly preferred are titanium compounds. Representative examples of preferred transition metal compounds include transition metal compounds whose general formulas are represented by formulas (1) to (3). Ti(OR) ₄ (1) (R is an alkyl group or allyl group (aryl) having at most 20 carbon atoms) M(acac) ₃ (2) MO(acac) ₂ (3) [(acac) is acetyl acetonate group, M is a transition metal of titanium, vanadine, iron, chromium, and cobalt. Typical examples of these transition metal compounds include, for example, tetramethoxytitanium, tetraethoxytitanium, tetran-propoxytitanium,
Tetraisopropoxytitanium, tetra n-butoxytitanium, tetraisobutoxytitanium, tetraoctadecyloxytitanium, tetraphenoxytitanium, trisacetylacetonate titanium, trisacetylacetonate vanadium, trisacetylacetonate iron, trisacetylacetonate Examples include chromium, cobalt trisacetylacetonate, titanium oxyacetylacetonate, vanadium oxyacetylacetonate, and the like. The organometallic compound used in the present invention is an organometallic compound containing at least one metal from group A, B, B, and B of the periodic table, and the general formula of some of them is represented by the following formula. It is something. MRn [However, M is A, B, B, or a metal from Group B of the periodic table, and R is a metal with a maximum number of carbon atoms.
20 alkyl groups, alkenyl groups, allyl groups, aralkyl groups, alkoxide groups,
An organic group selected from the group consisting of a phenoxy group and a cyclopentadienyl group, or a hydrogen atom or a halogen atom, which may be the same or different, but at least one of them is a hydrogen atom or the organic group. , n is the highest valence number of the metal or a positive integer less than that.] Other organometallic compounds include complexes of the above organometallic compound and equimolar amounts of pyridine, triphenylphosphine, or diethyl ether; Mention may be made of reactants of 1 mol of said organometallic compound with at most 2.0 mol of water as well as double salts of two of said organometallic compounds. Among the organometallic compounds used in the present invention, typical ones include those containing magnesium, calcium, zinc, boron, aluminum, gallium, silicon, and tin. Organometallic compounds of aluminum and tin are preferred, and organoaluminium-based compounds are particularly preferred. Typical examples of the organoaluminum compounds include triethylaluminum, triisobutylaluminum, trihexylaluminum, diethylaluminum chloride, di-n-butylaluminum chloride, ethylaluminum sesquichloride, diethylaluminium butoxide, and the reaction of triethylaluminum with water. The product [reaction ratio 1:0.5 (molar ratio)] is mentioned. Examples of other organoaluminum compounds include aluminum siloxalene compounds, aluminum amide compounds, dialmoxalene compounds, and double salts containing the above organoaluminum compounds. The general formula of the aluminum-siloxalene compound used as the organometallic compound in the present invention is shown by the following formula. [However, R ¹ , R ² and R ³ may be the same or different and are a halogen atom or an alkyl group or alkoxy group having at most 10 carbon atoms, and R ⁴ is an alkyl group having at most 10 carbon atoms. and R ⁵
is a halogen atom, an alkyl group or alkoxy group having at most 10 carbon atoms, or a general formula of

[expression] or

[Formula] (However, R ⁶ , R ⁷ and R ⁸ may be the same or different, and are the same as R ¹ , R ² and R ³ above, and n is
(a positive integer of 10 or less)] Representative examples of the aluminum-siloxalene compounds used in the present invention include trimethyldimethyl-siloxalene, trimethyldiethyl-siloxalene, and trimethyldi-n
-Propyl-siloxsalene, trimethyl-diisobutyl-siloxsalene, trimethyldioctyl-
Mention may be made of siloxsalene, trichlorodimethyl-siloxsalene, dimethylethyldiethyl-siloxsalene, trimethoxydimethyl-siloxsalene, triethyldimethyl-siloxsalene, trimethyldimethoxy-siloxsalene, trimethyldimethoxy-siloxsalene and trimethoxydichloro-siloxsalene. Further, the general formula of the aluminum amide compound used as the organometallic compound in the present invention is shown by the following formula. (However, R ¹ , R ² and R ³ may be the same or different and are a hydrogen atom or an alkyl group having at most 10 carbon atoms, and R ⁴ is a halogen atom or an alkyl group having at most 10 carbon atoms. Among the aluminum amide compounds used in the present invention, typical examples include diethylaluminum dimethylamide, diethylaluminum diethylamide, dimethylaluminum dimethylamide, dimethylaluminum di-n
-butyramide, diethylaluminium di-n-
butylamide, dichloroaluminum dimethylamide, dimethylaluminum dioctylamide,
Mention may be made of diisobutylaluminum di-n-butylamide and dihexylaluminum dioctylamide. The general formula of the dialxane compound used as the organometallic compound in the present invention is shown by the following formula. (However, R ¹ , R ² and R ³ may be the same or different and are a halogen atom or an alkyl group or alkoxy group having at most 10 carbon atoms, and R ⁴ is an alkyl group having at most 10 carbon atoms. Among the dialmoxane compounds used in the present invention, representative ones include tetramethyldialumoxane, tetraethyldialumoxane, tetraisobutyldialumoxane, and 1.1-
Dimethyl-3,3-diethyldialumoxane, tetraisobutyldialumoxane, 1,1-dimethyl-3,3-diisobutyldialumoxane, tetradecyldialumoxane, trimethyldialumoxane chloride and triethyldialumoxane chloride can give. Among the organometallic compounds used in the present invention, typical examples of organometallic compounds other than organoaluminum compounds include diethylmagnesium, ethylmagnesium chloride, methylmagnesium iodide,
Allyl magnesium chloride; normal propylmagnesium chloride, tertiary-butylmagnesium chloride, phenylmagnesium bromide, diphenylmagnesium, ethyl ethoxymagnesium, dimethylzinc, diethylzinc, diethoxyzinc, phenylcalcium iodide, dibutylboron chloride, diborein, trimethylboron, triethylsilane, silicon tetrahydride, triethylsilicone hydride, tetramethyltin, tetraethyltin, trimethyltin chloride, dimethyltin dichloride, trimethyltin hydride, ethylmagnesium bromide and ethyl ether Complexes and reaction products of diethylzinc and water [H ₂ O/Zn(C ₂ H ₅ ) ₂
<2.0 (molar ratio)]. Further, as the organic compound used in the present invention, double salts of two types of the above-mentioned organic compounds (for example, lithium aluminum tetrahydride,
calcium (tetraethylzinc). In carrying out the present invention, these organometallic compounds may be used alone or in combination of two or more. Although the ratio of the organometallic compound to the transition metal compound used is not particularly limited, it is generally preferable that the ratio of the organometallic compound to the transition metal of the transition metal compound is within the range of 1 to 100 in terms of molar ratio. A third component can be used in combination with these transition metal compounds and organometallic compounds, if necessary, to control the polymer yield, polymerization rate, etc. Third
Typical examples of the components include oxygen-containing compounds such as alcohols, peroxides, carboxylic acids, acid anhydrides, acid chlorides, esters, and ketones, as well as other nitrogen-containing compounds, sulfur-containing compounds,
Halogen-containing compounds, molecular iodine, other Lewis acids, etc. can also be used. The amount of the third component used is at most 20 times the mole of the transition metal. The polymerization solvent used in the present invention includes:
Any organic solvent can be used as long as it does not react with and deactivate the catalyst system. Specific examples of these organic solvents include aliphatic or aromatic hydrocarbons, aliphatic or aromatic ether compounds,
Examples include halogenated aliphatic or halogenated aromatic hydrocarbons, aliphatic or aromatic carboxylic acid esters, alicyclic compounds, and heterocyclic compounds, among which aliphatic or aromatic hydrocarbons, aliphatic It is particularly preferable to use aromatic ether compounds, alicyclic compounds and heterocyclic compounds. Typical examples of these compounds include pentane, hexane, heptane, octane, nonane, decane, dodecane, cyclohexane, tetrahydrofuran, dioxane, diethyl ether, ethyl methyl ether, benzene, toluene, xylene, ethylbenzene, methyl phenyl ether. (anisole), ethyl phenyl ether, diphenyl ether, dimethoxybenzene,
Examples include 1,3,5-trimethoxybenzene, chlorobenzene, dichlorobenzene, methyl benzoate, and ethyl benzoate. These compounds may be used alone or in combination of two or more. In order to obtain the acetylene polymer gel of the present invention, the concentration of the transition metal compound in the catalyst system should be in the range of 0.0001 to 0.1 mol, preferably 0.001 to 0.1 mol, based on 1 mol of the polymerization solvent. Polymerization is necessary, and if the concentration of the transition metal compound is 0.1 mol or more per 1 mole of polymerization solvent, it is difficult to obtain a gel-like material with good moldability. If the amount is less than 0.0001 mol per 1 mol of the polymerization solvent, most of the acetylene high polymer will be in powder form. The catalyst solution may be homogeneous or non-uniform, but from the viewpoint of easy catalyst removal, it is preferable that the catalyst solution be homogeneous. The order of addition of the catalyst system and acetylene in the polymerization reaction of the present invention is as follows. That is, the catalyst system is added to a polymerization solvent in which acetylene has been dissolved in advance, or the acetylene is dissolved in a polymerization solvent containing one of the catalyst components of the catalyst system, and then the other catalyst component is added, Next, acetylene to be polymerized is blown into the system to cause a polymerization reaction, thereby obtaining a gel-like product of an acetylene high polymer. Regardless of the above method, if a catalyst system is added to a polymerization solvent in which acetylene is not dissolved and acetylene gas is blown into it, a film-like or lump-like acetylene high polymer will be formed, and the acetylene high polymer will be It is difficult to obtain a gel-like material. The amount of acetylene dissolved in the polymerization solvent is not particularly limited, but it is preferable to dissolve the acetylene up to a saturated amount in the polymerization solvent. The polymerization temperature is not particularly limited, but is usually -
The temperature is preferably 100°C to 300°C, and particularly preferably -80°C to 200°C for ease of handling. In the present invention, the steric structure of the acetylene polymer produced can be controlled by adjusting the polymerization temperature and the preparation conditions of the catalyst system, but in general, the lower the polymerization temperature, the higher the flexible cis content. An acetylene high polymer is produced, and if the polymerization temperature is high, an acetylene high polymer with a high trans content is produced. Although there is no particular restriction on the pressure of acetylene gas during polymerization, it is practically preferable to carry out the polymerization at a pressure of 10 atmospheres or less. The catalyst can be removed from the acetylene polymer gel obtained by polymerization by the usual removal methods, such as washing with an organic solvent that dissolves the catalyst, but it does not specifically remove the catalyst. There is no problem in using it. The acetylene polymer gel obtained in this manner can be easily molded under pressure into a uniform molded article having any desired shape and wall thickness. Furthermore, a porous acetylene polymer obtained by freeze-drying a gel-like material can be pressure-molded to form a molded article having an arbitrary shape and wall thickness. By utilizing its electrical properties, the acetylene polymer obtained by the production method of the present invention is useful as an organic semiconductor material for producing parts of electronic devices such as electrical resistance elements, heat-sensitive elements, photosensitive elements, etc. It is. Hereinafter, the present invention will be explained in more detail with reference to Examples. Example 1 200 ml of toluene purified in a conventional manner as a polymerization solvent was charged into a glass reactor 1 that was completely purged with nitrogen gas. After cooling to -78°C and removing nitrogen gas from the system using a vacuum pump, 1 atm of acetylene gas was blown into the system to dissolve acetylene in a saturated amount. Next, as a catalyst, 2.94 mmol of tetrabutoxytitanium and 7.34 mmol of triethylaluminum were sequentially charged at -78°C to prepare a catalyst solution. The catalyst solution was a homogeneous solution. While the reactor remained cooled to -78°C, purified acetylene gas at a pressure of 1 atmosphere was bubbled through. At the beginning of the polymerization reaction, the entire system became agar-like. The polymerization reaction was continued for 24 hours while maintaining the acetylene gas pressure at 1 atm. The system was agar-like with a reddish-purple color. After the polymerization was completed, unreacted acetylene gas was removed, and the system was repeatedly washed four times with 200 ml of purified toluene while maintaining the temperature at -78°C. Even after washing, the solution remained slightly brownish and the catalyst was not completely removed. The gel-like acetylene polymer swollen in toluene was in the form of chips with intertwined fibrous microcrystals (fibrils), and no powder or lump-like polymer was produced. When this gel-like material was sandwiched between chromium-plated ferro plates and press-molded at room temperature under a pressure of 100 kg/cm ² , a flexible film of acetylene high polymer with a reddish-brown metallic luster was obtained. This film has electrical conductivity (DC four terminal method) of
It was a p-type semiconductor with a resistance of 9.4×10 ^-7 Ω ^-1 cm ^-1 at 20°C. Example 2 Acetylene polymerization was carried out in the same manner as in Example 1 using the same catalyst system as in Example 1, except that n-heptane was used instead of toluene as the polymerization solvent. Conduct, Example 1
A gel-like substance similar to that was obtained. The obtained gel-like material was pressure-molded in the same manner as in Example 1 to obtain a flexible film. Comparative Example 1 Acetylene was polymerized in exactly the same manner as in Example 1 using the same catalyst system as in Example 1, except that acetylene was not dissolved in toluene in advance. A thin polymer film was formed on the surface of the polymerization solvent at the initial stage of polymerization, and even after 24 hours of polymerization, only the film of acetylene high polymer on the surface of the polymerization solvent became thicker, and no gel-like material was obtained. Example 3 200 ml of anisole purified in a conventional manner as a polymerization solvent and 0.294 mmol of tetrabutoxytitanium as a catalyst were placed in a glass reactor (1) completely purged with nitrogen gas, cooled to -78°C, and vacuum-evacuated. After removing nitrogen gas from the system with a pump, 1
Acetylene gas was blown at atmospheric pressure to dissolve acetylene in a saturated amount. Next, 1.50 mmol of triisobutylaluminum was charged to prepare a catalyst solution. The catalyst solution was a homogeneous solution. The temperature of the reactor was returned to room temperature, and purified acetylene gas at a pressure of 1 atmosphere was blown into the reactor. Ten minutes after starting the polymerization reaction, the entire system turned into an agar-like gel. Polymerization was continued for 24 hours while maintaining the acetylene gas pressure at 1 atm. The entire system was agar-like with a blackish brown color. After the polymerization reaction was completed, unreacted acetylene gas was removed, and the product was washed four times with 200 ml of a mixed solvent of methanol and toluene at a ratio of 1:5 (volume ratio). The obtained gel-like material was the same gel-like material as in Example 1, and when it was pressure-molded in the same manner as in Example 1, a uniform film was obtained. This film was a P-type semiconductor with an electrical conductivity of 2.5×10 ^-6 Ω ^-1 ·cm ^-1 . Example 4 A catalyst was prepared and prepared in exactly the same manner as in Example 1, except that 5.0 mmol of titanium trisacetylacetonate and 25.0 mmol of triethylaluminum were used instead of the catalyst components tetrabutoxytitanium and triethylaluminum used in Example 1. A gel-like material similar to that in Example 1 was obtained by polymerizing acetylene. Example 5 A catalyst was prepared in exactly the same manner as in Example 1, except that 5.0 mmol of iron trisacetylacetonate and 15.0 mmol of triisobutylaluminum were used instead of the catalyst components tetrabutoxytitanium and triethylaluminum used in Example 1. Then, acetylene was polymerized to obtain a gel-like material similar to that in Example 1. Example 6 Instead of the catalyst components tetrabutoxytitanium and triisobutylaluminum used in Example 3,
A gel-like material similar to Example 3 was obtained by preparing a catalyst and polymerizing acetylene in the same manner as in Example 3, except that 0.5 mmol of trisacetylacetonatochromium and 2.5 mmol of triisobutylaluminum were used. Comparative Example 2 200 ml of toluene purified in a conventional manner was charged as a polymerization solvent into the glass reaction vessel of 1, which had been completely purged with nitrogen gas, cooled to -78°C, and the nitrogen gas in the system was removed using a vacuum pump. After removing 1 atm of acetylene gas, acetylene was dissolved in a saturated amount. Next, as a catalyst, 0.01 mmol of tetrabutoxytitanium and 0.1 mmol of triethylaluminum were sequentially charged at -78°C to prepare a catalyst solution. The catalyst solution was a homogeneous solution. The reactor was cooled with liquid nitrogen, and the nitrogen gas in the system was exhausted using a vacuum pump. Purified acetylene gas at a pressure of 1 atmosphere was blown into the reactor while cooling it to -78°C. As the polymerization began, a dark brown acetylene polymer began to precipitate in the form of a powder. The polymerization reaction was carried out at -78°C for 24 hours while maintaining the acetylene gas pressure at 1 atm.
The obtained acetylene high polymer was in powder form. This powdered acetylene high polymer is purified toluene.
After repeated washing with 200 ml four times, vacuum drying was performed to obtain a powdered acetylene high polymer. When this powdered acetylene high polymer was sandwiched between chromium-plated ferro plates and press-molded at a pressure of 100 kg/cm ² at room temperature, the molded product obtained was extremely brittle and could not be obtained in the form of a film. Comparative Example 3 200 ml of toluene purified in a conventional manner as a polymerization solvent was placed in the glass container 1 that had been completely purged with nitrogen gas, cooled to -78°C, and nitrogen gas in the system was removed using a vacuum pump. After removal, 1 atm of acetylene gas was blown into the solution to dissolve acetylene in a saturated amount. Next, 40 mmol of tetrabutoxytitanium and 80 mmol of triethylaluminum were sequentially charged as a catalyst to prepare a catalyst solution. The catalyst solution was a homogeneous solution. When acetylene was polymerized using the obtained catalyst solution in exactly the same manner as in Example 1, some of the acetylene high polymer was in the form of a gel.
Most of the acetylene polymers were solid lumps with phase separation. Post-treatment was carried out in the same manner as in Example 1, and then Example 1
When pressure molding was carried out in the same manner as above, a uniform film could not be obtained.

Claims (1)

[Claims] 1. In a method for producing an acetylene polymer by polymerizing acetylene using a catalyst system containing a transition metal compound and an organometallic compound as main components, the transition metal compound is added to 1 part of the polymerization solvent.
After adding the catalyst system to a polymerization solvent used at a molar concentration of 0.0001 to 0.1 and in which acetylene has been previously dissolved, or dissolving acetylene in a polymerization solvent containing the catalyst component of one of the catalyst systems,
1. A method for producing a gel-like product of an acetylene high polymer, which comprises performing polymerization by adding other catalyst components.