JPH07300529A - Polysilane and its production - Google Patents

Abstract

PURPOSE:To produce, at a high yield under mild conditions, a polysilane which exhibits a high electric conductivity when doped and is suitable as a photoelectric conversion material or a conductive material by subjecting a specific trihydrosilane to condensation by dehydration. CONSTITUTION:A trihydrosilane of formula I [wherein X is halogen, alkyl, fluoroalkyl, alkoxy. (substd.) amino, acyl, or an aldehyde group; Y is H, halogen, alkyl, fluoroalkyl, (substd.) amino, acyl, or an aldehyde group provided that X and Y may combine with each other to form an alkylene or heteroalkylene group and that when Y is H, then X is not alkyl nor fluoroalkyl; m is 1-5; and k is 0-4 provided k+m is 1-5] is subjected to condensation by dehydration to give a polysilane of formula II (wherein X, Y, m, and k each is the same as described above; and n>=3). Thus, a polysilane exhibiting a high electric conductivity when doped and suitable as a photoelectric conversion material, an electric conductive material, etc., is obtd. at a high yield under relatively mild conditions.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a novel polysilane useful as a photoelectric conversion material, a conductive material, a ceramic precursor and the like, and a method for producing the same.

[0002]

2. Description of the Related Art Conventionally, the problems to be solved by the invention
The Wurtz reaction is often used for the synthesis of polysilanes, but there are many difficulties in obtaining polysilanes containing a functional group due to severe reaction conditions. Also, Hayase et al. ((A)
R. Horiguchi, Y. Onishi, S .; Ha
yase, Macromolecules, (199
2), 25 , 3825. (B) S. Hayase, R .;
Horiguchi, Y. Onishi, Macrom
olecules, (1989), 22 , 2933.
(C) C.I. H. Yuan, R .; West, Macrom
olecules, (1993), 26 , 2654. )
Reports a polysilane with alcohol or phenol functionality using a trialkylsilyl protecting group.
It is necessary to devise the type of protecting group and reaction conditions, and delicate adjustment of reaction conditions is required for elimination of the protecting group, and thus their synthesis is not easy. Furthermore, Seki et al. (T. Sek
i, T. Tamaki, K .; Ueno, Macromo
lecules, (1992), 25 , 3825. )
Reported the introduction of an ammonium functional group after synthesizing a polysilane, but the two-step modification of the polymer had problems in stability and reaction rate,
It was difficult to obtain these compounds in high yield and high purity.

On the other hand, in the synthesis of polysilane by the dehydrogenative condensation method, the improvement of the degree of polymerization is conventionally considered to be a problem, and the main focus of the research is to raise the activity of the catalyst to obtain a high polymer. Application to the introduction of substituents has low functionality such as methyl group and trifluoromethyl group (J.
P. Banovetz, H .; Suzuki, R .; M. W
AYOUTH, Organometallics,
(1993), 12 , 4700. ) Was only reported.

[0004]

Means and Actions for Solving the Problems The present inventor has conducted extensive studies on polysilane useful as a photoconversion material and a conductive material. As a result, the functional group-substituted phenyltrihydrosilane represented by the following general formula (2) It was found that the polysilane having a functional group-substituted phenyl group and a side chain hydrogen group represented by the following general formula (1) can be obtained under a relatively mild condition by subjecting the formula (1 ) Polysilane shows high conductivity by doping with an oxidizing substance such as iodine, is useful as a light conversion material and a conductive material, and is also useful as a ceramic precursor, and forms the present invention. I arrived.

[0005]

[Chemical 3] (In the formula, X represents a halogen atom, an alkyl group, a fluoroalkyl group, an alkoxy group, a substituted or unsubstituted amino group,
It represents an acyl group or an aldehyde group, and Y represents a hydrogen atom, a halogen atom, an alkyl group, a fluoroalkyl group, a substituted or unsubstituted amino group, an acyl group or an aldehyde group. Alternatively, X and Y together form a divalent alkylene group or heteroalkylene group. However, when Y is a hydrogen atom, X is not an alkyl group or a fluoroalkyl group. m is an integer of 1 to 5 and k is an integer of 0 to 4, and k + m =
1 to 5, and n represents an integer of 3 or more. )

Therefore, the present invention provides a polysilane represented by the general formula (1) and a polysilane represented by the general formula (1), characterized by dehydrogenative condensation of the trihydrosilane represented by the general formula (2). A manufacturing method is provided.

The present invention will be described in more detail below. The polysilane of the present invention is represented by the following general formula (1).

[0008]

[Chemical 4]

Here, X is a halogen atom such as Cl or Br, a methyl group, an ethyl group or the like, preferably having 1 to 2 carbon atoms.
0, especially 1 to 6 C _m F _{2m + 1} such as an alkyl group or trifluoropropyl group (m is preferably 1 to 20, particularly 1 to 3)
And preferably a C1-20, especially C1-6 alkoxy group such as a fluoroalkyl group, a methoxy group, an ethoxy group, a substituted or unsubstituted amino group, an acyl group, or an aldehyde group. Y represents a hydrogen atom, the same halogen atom as described above, an alkyl group, a fluoroalkyl group, a substituted or unsubstituted amino group, an acyl group, or an aldehyde group. In this case, when Y is a hydrogen atom, X does not become an alkyl group or a fluoroalkyl group. Examples of the substituted amino group include an alkylamino group in which one or two hydrogen atoms of the amino group are substituted with an alkyl group having 1 to 20 carbon atoms, particularly 1 to 4 carbon atoms. Or
X and Y together form a divalent alkylene group or heteroalkylene group, for example, an aromatic ring or a heterocycle such as a phenyl group. Thus the X- (C ₆ H ₃₎ -Y include, for example, polynuclear aromatic or heterocyclic rings such as naphthyl. Further, m represents an integer of 1 to 5 and k represents an integer of 0 to 4, and k + m = 1.
~ 5.

Further, in the formula (1), n is an integer of 3 or more, preferably 6 or more, more preferably 10 or more, and the upper limit thereof is not particularly limited, but it is usually large as long as it is soluble in a solvent. It is preferable.

The weight average molecular weight of the polysilane of the above formula (1) is preferably 400 or more, particularly 600 or more from the viewpoint of film-forming property.

The polysilane of the formula (1) can be obtained by dehydrogenative condensation of trihydrosilane represented by the following general formula (2).

[0013]

[Chemical 5] (However, X, Y, m, and k have the same meanings as above.)

Here, as the trihydrosilane of the formula (2), for example, p-dimethylaminophenylsilane, β
Examples include -silylnaphthalene, p-anisylsilane, and 3,4-methylenedioxyphenylsilane.

The above dehydrogenative condensation reaction of trihydrosilane can be carried out at room temperature or under heating conditions using a catalyst for dehydrogenative condensation reaction. As the catalyst, any catalyst used in a general dehydrogenative condensation reaction can be used, but a zirconocene or titanocene-based catalyst is particularly preferable. The amount of the catalyst used is a usual amount of catalyst, and is 0.001 to 20% by weight, particularly 0.01 to 1% by weight, based on the silane.
It is preferable that

A solvent is not essential for this reaction, but an aprotic solvent that does not react with hydrosilanes, such as tetrahydrofuran (THF), toluene,
It is preferable to use hexane or the like. Reaction temperature is 0 ℃
The temperature is preferably 200 ° C., particularly room temperature to 110 ° C., and the reaction time is generally 3 to 240 hours, particularly 12 to 70 hours.

The polysilane of the formula (1) according to the present invention is used as a ceramic precursor and is doped with an oxidizing substance such as iodine or ferric chloride to obtain a concentration of 10 ^{-2 -1.}
Since it has a high conductivity of about 0 ⁻⁵ S / cm, it is suitably used as a photoelectric conversion material and a conductive material.

[0018]

EXAMPLES The present invention will be specifically described below by showing Examples and Comparative Examples, but the present invention is not limited to the following Examples.

The average molecular weights of the following polymers are GP
The polystyrene equivalent weight average molecular weight by C is shown.

Example 1 2.626 g (17.35 mmol) of p- (N, N-dimethylanilino) silane was added to T
In HF, in the presence of 3 mg of a zirconocene catalyst represented by the following formula,
When the reaction was carried out at 105 ° C for 72 hours in a sealed tube, the yield was 9
A polymer of M _w = 1330 and M _n = 1260 was obtained at 4.3%.

[0021]

[Chemical 6]

It was confirmed by the IR spectrum shown in FIG. 1 that this polymer retains the basic structure of aromatic tertiary amine, para-substituted phenyl, Si--H, etc., and it was confirmed that the polymer was a polysilane of the following formula. It was IR spectrum: 2973 C-H 2078 Si-H 1593,1508 p-substituted aromatic C-C 1352 aromatic tertiary amine C-N.

[0023]

[Chemical 7]

Example 2 According to Example 1, 2.022 g (14.62 mmol) of p-anisylsilane was added to TH.
10 mg in a sealed tube in the presence of 2 mg of zirconocene catalyst in F.
When reacted at 5 ° C. for 72 hours, the yield was 87.3% and M
A polysilane represented by the following formula with _w = 950 and _Mn = 890 was obtained. IR spectrum: 3059 aromatic C-H 2956,2835 C-H 2104 Si-H 1591,1498 p-substituted aromatic C-C 1030 C-O-C.

[0025]

[Chemical 8]

Example 3 According to Example 1, 1.225 g (7.74 mmol) of β-silylnaphthalene was added to TH.
10 mg in a sealed tube in the presence of 4 mg of zirconocene catalyst in F.
When reacted at 5 ° C for 72 hours, the yield was 90.8% and M
A polysilane represented by the following formula with _w = 1170 and M _n = 1140 was obtained. IR spectrum: 2080 Si-H 850,814,740 β-substituted naphthalene C-H

[0027]

[Chemical 9]

Example 4 According to Example 1, 4.595 g (36.4 mmol) of p-fluorophenylsilane in a 1: 1 mixed solvent of THF / xylene in the presence of 3 mg of a zirconocene catalyst was sealed. When the reaction was carried out at 105 ° C. for 72 hours, the yield was 88.46% and M _w = 940, M _n =
A polysilane represented by the following formula of 900 was obtained. IR spectrum: 2960,2874 C-H 2127 Si-H 1588,1496 p-substituted aromatic C-C 1235 aromatic C-F.

[0029]

[Chemical 10]

[Embodiment 5] In accordance with Embodiment 1, 3,4-
3.789 g of methylenedioxyphenylsilane (24.
105 mmol) in a 1: 1 mixture of THF / xylene in the presence of 4 mg of zirconocene catalyst in a sealed tube.
When the reaction was performed at 72 ° C for 72 hours, the yield was 72% and M _w = 8.
As a result, a polysilane represented by the following formula with 40 and M _n = 810 was obtained.

[0031]

[Chemical 11] IR spectrum: 2963,2900 C-H 2157 Si-H 1502,1480 Substituted aromatic C-C 1262,1235 C-O-C.

Reference Example 1 Poly (p-dimethylaminophenylsilane) of Example 1 (M _w = 1170, M _n = 11)
The THF solution of 30) was spin-coated on a substrate, and the conductivity was measured while performing vapor-phase iodine doping.
It was 7 × 10 ⁻³ S / cm.

Reference Example 2 Poly (β-naphthylsilane) of Example 3 (M _w = 1170, M _n = 1140) THF
The solution was spin-coated on a substrate, and the conductivity was measured while performing vapor-phase iodine doping. The result was 4 × 10 ^-4 S /
It was cm.

The electrical conductivity was measured by measuring the direct current resistance by a four-terminal method while vapor phase doping the spin-coated film, and obtaining a stable value and then using it for calculating the electrical conductivity. .

[0035]

EFFECT OF THE INVENTION The polysilane of the present invention exhibits high conductivity by doping, and is suitably used as a photoelectric conversion material, a conductive material and the like. Further, according to the manufacturing method of the present invention,
The polysilane can be produced in high yield under relatively mild conditions.

[Brief description of drawings]

1 is an infrared absorption spectrum of polysilane of Example 1. FIG.

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

Claims (2)

[Claims] 1. A polysilane represented by the following general formula (1). [Chemical 1] (In the formula, X represents a halogen atom, an alkyl group, a fluoroalkyl group, an alkoxy group, a substituted or unsubstituted amino group,
It represents an acyl group or an aldehyde group, and Y represents a hydrogen atom, a halogen atom, an alkyl group, a fluoroalkyl group, a substituted or unsubstituted amino group, an acyl group or an aldehyde group. Alternatively, X and Y together form a divalent alkylene group or heteroalkylene group. However, when Y is a hydrogen atom, X is not an alkyl group or a fluoroalkyl group. m is an integer of 1 to 5 and k is an integer of 0 to 4, and k + m =
1 to 5, and n represents an integer of 3 or more. ) 2. The method for producing a polysilane according to claim 1, wherein the trihydrosilane represented by the following general formula (2) is dehydrogenated and condensed. [Chemical 2] (However, in the formula, X and Y and m and k have the same meanings as described above.)