JPH07149910A - Condensed polycyclic aromatic pendant polysilane, its production, and conductive polymer - Google Patents

Abstract

PURPOSE:To obtain the polysilane useful as a photoconductive or conductive material by reacting a diorganodihalogenosilane with a condensed polycyclic arom. dihalogenosilane in an inert solvent in the presence of an alkali metal. CONSTITUTION:The polysilane is represented by the formula: [(R<1>R<2>Si)k(R<3>R<4> Si)m]nd {wherein R<1>, R<2>, R<3>, and R<4> are each H or a monovalent hydrocarbon group provided at least either R<3> or R<4> is a monovalent hydrocarbon group having a condensed polycyclic arom. group of the formula: R<5>-CpH2p (wherein R<5> is a condensed polycyclic arom. group; and p is an integer of 1-12); and 0<=k<1, 0<m<=1, k+m=1, and n is an integer of 6 or higher} and is obtd. by reacting a diorganodihalogenosilane of the formula: R<1>R<2>SiX2 with a condensed polycyclic arom. dihalogenosilane of the formula: R<3>R<4>SiX2 (wherein X is halogen).

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to novel polycyclic fused aromatic group pendant polysilanes useful as photoconductive materials, conductive materials, etc., a method for producing the same, and a conductive polymer.

[0002]

PRIOR ART AND PROBLEMS TO BE SOLVED BY THE INVENTION Conventional polysilanes are mainly those having an alkyl group represented by a methyl group or a phenyl group as a substituent (RW).
est et al. J. Am. Chem. So
c. , 103 , 7352 (1981)).

After that, polysilane having a substituent containing hydrogen as a substituent or a reactive carbon-carbon double bond and polysilane having a halogenated alkyl group have been synthesized, and the polysilane can be crosslinked. As a result, the expectations for application have increased (R. West et
al. J. Organomet. Chem. , 30
0 , 327 (1986)).

In recent years, it has been reported that polysilane having a silyl group introduced as another substituent (Japanese Patent Laid-Open No. 63-12636) or polysilane having a phenolic substituent introduced into a resist material. (Japanese Patent Laid-Open No. 63-113021).

The present inventors have paid attention to the photoconductivity and electroconductivity of polysilane, and have developed a polysilane whose photodegradability is suppressed by introducing a substituent containing a carbazolyl group into polysilane, and previously proposed it. (JP-A-5-4370)
No. 2).

However, there is a demand for polysilanes which have higher electric conductivity and can be effectively used as photoconductive materials and conductive materials.

[0007]

Means and Actions for Solving the Problems The present inventors have
As a result of further studies to meet the above-mentioned demand, a diorganohalogenosilane represented by the following general formula (2) and a polycyclic fused aromatic group-containing dihalogenosilane represented by the following general formula (3), or the following general formula A novel polycyclic fused aromatic aromatic compound represented by the following general formula (1) is obtained by reacting a polycyclic fused aromatic group-containing dihalogenosilane of the formula (3) in the presence of an alkali metal in an inert solvent. The group-pendant polysilanes are obtained, and the electrical conductivity of the polycyclic condensed aromatic group-pendant polysilanes doped with an oxidizing dopant such as iodine is, for example, 10 ⁻⁴ to 10 ⁻⁵ S /.
The electric conductivity of dibutylpolysilane (3.5 × 10 ⁻⁸ S / cm) or methylphenylpolysilane (1.3 × 10 ⁻⁶ S / cm), which is about cm and does not have polycyclic fused aromatic groups, is obtained. The present invention has also been improved, and accordingly, the present invention has been completed by finding that it can be effectively used as a photoconductive material or a conductive material.

[0008]

[Chemical 1] (However, in the formula, R ¹ , R ² , R ³ and R ⁴ are each a hydrogen atom or a monovalent hydrocarbon group, and at least one of R ³ and R ⁴ is
One is a monovalent hydrocarbon group containing a polycyclic fused aromatic group represented by the following formula. Further, k, m, and n are 0 ≦ k <1,0
<M ≦ 1, k + m = 1, n ≧ 6. X is a halogen atom. )

R ⁵ —C _p H _2p — (wherein R ⁵ is a polycyclic fused aromatic group, p is 1 ≦ p ≦
It is an integer of 12. )

Therefore, the present invention provides the polycyclic fused aromatic group pendant polysilanes represented by the general formula (1), the diorganohalogenosilane represented by the general formula (2) and the general formula (3). The polycyclic fused aromatic group-containing dihalogenosilane represented by the formula or the polycyclic fused aromatic group-containing dihalogenosilane of the formula (3) is reacted in the presence of an alkali metal in an inert solvent. Provided are a method for producing polysilanes, and a conductive polymer obtained by doping the polysilanes with an oxidizing dopant.

The present invention will be described in more detail below. The novel polycyclic fused aromatic group pendant polysilanes of the present invention are represented by the following general formula (1).

[(R ¹ R ² Si) _k (R ³ R ⁴ Si) _m ] _n (1) (wherein R ¹ , R ² , R ³ and R ⁴ are each a hydrogen atom or a monovalent group) A hydrocarbon group, but at least one of R ³ and R ⁴
One is a monovalent hydrocarbon group containing a polycyclic fused aromatic group represented by the following formula. Further, k, m, and n are 0 ≦ k <1,0
<M ≦ 1, k + m = 1, n ≧ 6. )

R ⁵ —C _p H _2p — (wherein R ⁵ is a polycyclic fused aromatic group, p is 1 ≦ p ≦
12, preferably an integer of 1 ≦ p ≦ 6. )

The monovalent hydrocarbon group of R ¹ and R ² has 1 to 12 carbon atoms, particularly 1 to 6 carbon atoms, specifically, alkyl groups such as methyl, ethyl, propyl and butyl, and cyclohexyl. Examples thereof include a cycloalkyl group such as a group and an aryl group such as a phenyl group. R ³ and R ⁴ are a hydrogen atom, a monovalent hydrocarbon group similar to R ¹ and R ² , or R ⁵
-C _p H _2p - at and at least one of R ^3, R ⁴ is R ⁵ -
C _p H _2p −, and the polycyclic fused aromatic group of R ⁵ includes naphthyl group, anthracenyl group, phenanthrenyl group, benzophenanthrenyl group, pyrenyl group, chrysenyl group, naphthacenyl group and picenyl group. , A perenyl group,
Examples thereof include a coronenyl group and an ovalenyl group, and the polycyclic fused aromatic group may be unsubstituted or substituted with a monovalent hydrocarbon group or the like.

Although n is an integer of 6 or more, preferably 10 to 10,000, more preferably 100 to 1
When it is used as a photoconductive material or a conductive material, the polymerization degree is preferably high in order to fully exhibit its characteristics. The weight average molecular weight is usually 5,000 to 5,000,000 in terms of polystyrene.
0, especially 10,000 to 2,000,000.

The polysilanes of the above formula (1) include the diorganohalogenosilane represented by the following general formula (2) and the polyhalogenated condensed aromatic group-containing dihalogenosilane represented by the following formula (3), or the formula ( It can be synthesized by reacting the polycyclic fused aromatic group-containing dihalogenosilane of 3) in the presence of an alkali metal in an inert solvent.

R ¹ R ² SiX ₂ (2) R ³ R ⁴ SiX ₂ (3) (wherein R ^{1 to} R ⁴ have the same meanings as described above, and X is a halogen atom).

The chlorosilanes containing a polycyclic fused aromatic group may be either monopendant type or dipendant type, and the polycyclic fused aromatic group may be unsubstituted or substituted with an organic group. . Further, although one-dimensional polymers or cyclics are produced by using dihalosilanes, it is also possible to obtain network-like polysilanes by using trifunctional trihalosilanes. Furthermore, it is also possible to use halosilanes containing a carbon-carbon unsaturated bond in the main chain skeleton in advance.

The above dihalogenosilane is used in an inert solvent,
The reaction is carried out in the presence of an alkali metal, but as the inert solvent, one or more kinds of xylene, toluene, dodecane, ethers, esters and the like are used, and Na and the like are used as the alkali metal. In this case, the amount of the alkali metal used is preferably 2 to 3 times the mol of the dihalogenosilane.

The reaction temperature is 50 to 200 ° C., especially 100 to
The temperature is preferably 150 ° C., and the reaction time is usually 1 to 1
It's 0 hours.

After the reaction, methanol or the like is added to deactivate the alkali metal, the organic layer is collected, and after concentration, the target polysilane is precipitated with acetone or the like to collect the polysilane.

The polycyclic fused aromatic group pendant polysilanes of the present invention thus obtained have a high electric conductivity when doped with an oxidizing dopant, and are therefore suitable as a photoconductive material or a conductive material. Used for.

That is, as the oxidative dopant for making the polysilane conductive, halogens such as chlorine, bromine and iodine, tin chloride, transition metal chlorides such as ferric chloride, antimony pentafluoride, Lewis acids such as arsenic pentafluoride are effective, but it is preferable to dope with iodine or ferric chloride that is safe and easy to handle. The doping method includes (1) so-called vapor phase (or dry type) doping in which a vapor atmosphere of iodine, ferric chloride, etc. is exposed, and (2) a solution in which iodine, ferric chloride, etc. are dissolved in an inert solvent. Wet doping, in which the polymer is immersed in (3) When the polymer is dissolved in a solution in which iodine, ferric chloride, etc. are dissolved, the film is formed into a film or coating by dry film formation from this solution, and at the same time, doping is performed. A method such as simultaneous doping is used.

In this case, the inert solvent used in the wet doping or co-doping of (2) and (3) is a solvent which does not deactivate the ability as an electron-accepting compound by reacting with iodine or ferric chloride. And hydrocarbons such as hexane, octane and cyclohexane, aromatics such as toluene, xylene and nitrobenzene, ethers, ethers such as tetrahydrofuran, esters such as ethyl acetate, methanol, Alcohols such as ethanol, dimethylformamide,
Examples include aprotic polar solvents such as dimethyl sulfoxide and hexamethylphosphoric triamide, and nitromethane and acetonitrile.

Among them, a solvent such as tetrahydrofuran is particularly suitable for co-doping because it dissolves the polymer very well. According to this co-doping method, a polymer can be dissolved in a solution containing a dopant, and the solution can be cast and dried to obtain a doped conductor. The drying temperature is usually 0 to 1.
It is preferably carried out at 50 ° C., atmospheric pressure or reduced pressure.

However, in the wet method and the simultaneous doping method,
Often the polymer is degraded by the dopant and may gel or decompose. On the other hand, the vapor phase doping of (1) is particularly useful because it does not use a solvent, is easy to dry, and has high conductivity.

In vapor phase doping, the doping rate can be controlled by controlling the temperature and pressure of the dopant atmosphere. Here, in the case of doping with iodine or antimony pentafluoride, the temperature is generally -30 ° C to 2 ° C.
It is preferably carried out in the range of 00 ° C. At lower temperatures, the doping rate is slower, and at higher temperatures, polymer degradation may occur during doping. Also,
The pressure of the dopant atmosphere is 0.001 mmHg-38.
It is preferably performed in the range of 00 mmHg. At a lower pressure than that, the doping rate is slow, and at a higher pressure, it is difficult to expect an increase in the doping rate even if the pressure is increased. In addition,
With iodine and antimony pentafluoride, doping proceeds rapidly at room temperature and atmospheric pressure, but in the case of ferric chloride, the doping conditions differ from those of iodine and antimony pentafluoride because of the low vapor pressure. Ferric chloride doping is generally preferably performed at a temperature in the range of 50 ° C to 300 ° C. If the temperature is lower than that, the doping rate is slow, and if the temperature is higher than that, deterioration of the polymer may occur during doping. The pressure is preferably 0.001 mmHg to 760 mmHg. At lower pressures, it takes a long time to reach that pressure, which is not economical, and at higher pressures, the doping rate becomes very slow. More preferably, the ferric chloride doping is performed at a pressure of 0.1 mmHg to 10 mmHg and a temperature range of 50 ° C. to 200 ° C. in order to effectively increase the conductivity of the polymer. According to this method, a conductive material can be produced by using ferric chloride, which is less toxic, without using a flammable solvent by a very simple operation.

[0028]

INDUSTRIAL APPLICABILITY The polycyclic fused aromatic group pendant polysilanes of the present invention exhibit high electric conductivity by doping and are useful as photoconductive materials, conductive materials and the like. Further, according to the production method of the present invention, such polysilanes can be easily and surely synthesized.

The conductive polysilane of the present invention has excellent shapeability and can be easily formed as a highly conductive film or coating film, so that it can be used for battery electrodes, solar cells, electromagnetic shield casings, etc. It can be widely used in the electronic, communication fields.

[0030]

The present invention will be described in more detail with reference to the following examples, but the present invention is not limited to the following examples.

[0031]

[Chemical 2]

Metallic sodium 0.7 g under nitrogen atmosphere
15 g of xylene was added to (30 mmol), the temperature was raised to 138 ° C., and the mixture was vigorously stirred to prepare a sodium dispersion.

0.56 g (2 mm of 3- (1-naphthyl) propylmethyldichlorosilane) was added to this dispersion.
ol) and methylphenyldichlorosilane 1.91 g (1
0 mmol) was added over 2 minutes, and the mixture was stirred at 138 ° C. for 4 hours. After the completion of the reaction, the mixture was cooled to room temperature, and about 5 ml of methanol was added dropwise to deactivate the remaining sodium, followed by washing with water. The organic layer was then removed, dried over calcium chloride and the reaction mixture was concentrated. The obtained viscous substance was added to 100 ml of acetone to precipitate a polymer.
The precipitate was filtered off and dried in a vacuum to obtain 0.15 g of the target naphthyl group pendant polysilane as a white precipitate.

According to GPC analysis, the weight-average molecular weight distribution of this polymer consisted of two components and was 51 in terms of polystyrene.
It was 6,300 (10%) and 11,500 (90%). Also, the ultraviolet absorption derived from polysilane (λmax
337 nm) was confirmed.

[0035]

[Chemical 3]

0.92 g of metallic sodium under a nitrogen atmosphere
15 g of xylene was added to (40 mmol), the temperature was raised to 138 ° C., and the mixture was vigorously stirred to prepare a sodium dispersion.

1.42 g (5 mm) of 3- (1-naphthyl) propylmethyldichlorosilane was added to this dispersion.
ol) and methylphenyldichlorosilane 1.91 g (1
0 mmol) was added over 1 minute, and the mixture was stirred at 138 ° C. for 5 hours. After the completion of the reaction, the mixture was cooled to room temperature, and about 5 ml of methanol was added dropwise to deactivate the remaining sodium, followed by washing with water. The organic layer was then removed, dried over calcium chloride and the reaction mixture was concentrated. The obtained viscous substance was added to 100 ml of acetone to precipitate a polymer.
The precipitate was separated by filtration and vacuum dried to obtain 0.34 g of the naphthyl group pendant polysilane which was the target as a white precipitate.

According to GPC analysis, the weight average molecular weight distribution of this polymer consisted of two components and was 24 in terms of polystyrene.
It was 3,700 (11%) and 11,500 (89%). Also, the ultraviolet absorption derived from polysilane (λmax
336 nm) was confirmed.

[0039]

[Chemical 4]

0.7 g of metallic sodium under a nitrogen atmosphere
15 g of xylene was added to (30 mmol), the temperature was raised to 138 ° C., and the mixture was vigorously stirred to prepare a sodium dispersion.

0.67 g of 3- (1-phenanthrenyl) propylmethyldichlorosilane was added to this dispersion.
(2 mmol) and methylphenyldichlorosilane 1.9
1 g (10 mmol) was added in 2 minutes, and it stirred at 138 degreeC for 4 hours. After the completion of the reaction, the mixture was cooled to room temperature, and about 5 ml of methanol was added dropwise to deactivate the remaining sodium, followed by washing with water. The organic layer was then removed, dried over calcium chloride and the reaction mixture was concentrated. The obtained viscous substance was added to 100 ml of acetone to precipitate a polymer. The precipitate was filtered off and dried in vacuum to obtain 0.50 g of the target phenanthrenyl group pendant polysilane as a white precipitate.

According to GPC analysis, the weight average molecular weight distribution of this polymer consisted of two components and was 37 in terms of polystyrene.
It was 6,400 (11%) and 7,900 (89%). Also, the ultraviolet absorption derived from polysilane (λmax
336 nm) was confirmed.

[0043]

[Chemical 5]

0.92 g of metallic sodium under a nitrogen atmosphere
15 g of xylene was added to (40 mmol), the temperature was raised to 138 ° C., and the mixture was vigorously stirred to prepare a sodium dispersion.

1.66 g of 3- (1-phenanthrenyl) propylmethyldichlorosilane was added to this dispersion.
(5 mmol) and methylphenyldichlorosilane 1.9
1 g (10 mmol) was added over 1 minute, and the mixture was stirred at 138 ° C. for 4 hours. After the completion of the reaction, the mixture was cooled to room temperature, and about 5 ml of methanol was added dropwise to deactivate the remaining sodium, followed by washing with water. The organic layer was then removed, dried over calcium chloride and the reaction mixture was concentrated. The obtained viscous substance was added to 100 ml of acetone to precipitate a polymer. The precipitate was filtered off and dried in vacuum to obtain 1.40 g of the desired phenanthrenyl group pendant polysilane as a white precipitate.

According to GPC analysis, the weight average molecular weight distribution of this polymer consisted of two components and was 93 in terms of polystyrene.
It was 7,300 (15%) and 5,250 (85%). Also, the ultraviolet absorption derived from polysilane (λmax
336 nm) was confirmed.

[Examples 5 and 6, Comparative Examples 1 and 2] The polycyclic aromatic group pendant polysilanes obtained in Examples 2 and 4 were doped with iodine and the electrical conductivity thereof was measured.
Table 1 also shows the results of (Bu ₂ Si) _n and (MePhSi) _n as comparative examples.

[0048]

[Table 1]

The conductivity is measured by forming four terminals on a glass plate by platinum vapor deposition to form electrodes, and spin-coating a polymer solution dissolved in a solvent on the electrodes to form a thin film and conduct the conductivity. This sample was used as a rate measurement sample, and this was contacted with iodine under light-tightness and sealing, and the change in direct-current resistance with time was traced. High conductivity is also exhibited when ferric chloride is doped by the same conductivity measuring method.

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Shigeru Mori 3-2-1 Sakado, Takatsu-ku, Kawasaki-shi, Kanagawa Shin-Etsu Chemical Co., Ltd. Corporate Research Center

Claims (3)

[Claims] 1. A polycyclic fused aromatic group pendant polysilane represented by the following general formula (1). [(R ¹ R ² Si) _k (R ³ R ⁴ Si) _m ] _n (1) (wherein R ¹ , R ² , R ³ and R ⁴ are each a hydrogen atom or a monovalent hydrocarbon group) However, at least one of R ³ and R ⁴
One is a monovalent hydrocarbon group containing a polycyclic fused aromatic group represented by the following formula. Further, k, m, and n are 0 ≦ k <1,0
<M ≦ 1, k + m = 1, n ≧ 6. _{^{) R 5 -C p H 2p -}} ( provided that wherein R ⁵ is a polycyclic fused aromatic groups, p is 1 ≦ p ≦
It is an integer of 12. ) 2. A diorganohalogenosilane represented by the following general formula (2) and a polycyclic condensed aromatic group-containing dihalogenosilane represented by the following general formula (3), or a polycyclic condensed compound of the formula (3). The method for producing polysilanes according to claim 1, wherein the aromatic group-containing dihalogenosilane is reacted in an inert solvent in the presence of an alkali metal. R ¹ R ² SiX ₂ (2) R ³ R ⁴ SiX ₂ (3) (wherein R ^{1 to} R ⁴ have the same meanings as defined in claim 1, X is a halogen atom) is there.) 3. A conductive polymer obtained by doping the polycyclic fused aromatic group pendant polysilanes according to claim 1 with an oxidizing dopant.