JPH05262881A - Polysilane having both molecular ends chlorinated and its production - Google Patents

Abstract

PURPOSE:To facilitate the synthesis of the title polysilane which has a degree of polymn. of 5 or higher, esp. 10 or higher, into which various functional groups can be introduced, and which is suitable as a material for producing a copolymer with another polymer. CONSTITUTION:A soln. of a high-mol.-wt. polysilane in a chlorinated hydrocarbon solvent is irradiated with ultraviolet rays in an inert gas atmosphere to give the title polysilane of the following formula: wherein R<1>, R<2>, R<3>, and R<4> are each independently a 1-12C alkyl group or an optionally substd. aryl group; and 0<=n<=10, 0<=m<=10, n+m>=10, and k>=1.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a chloropolysilane having both terminals which can introduce various functional groups and is suitable as a raw material for producing a copolymer with another polymer, and a method for producing the same.

[0002]

2. Description of the Related Art Conventionally, the problems to be solved by the invention
A general industrial production method of polysilane is described in “Journal of Polymer Science: Polymer Chemistry Edition, Vol. 22, 159-170 (1).
984) "," Journal of Organometallic Chemistry, Vol. 300, p327 (198).
6) ”,“ Journal of Polymer Science:
Polymer Letter Edition, Vol. 21, p8
19 (1983) ”, it was a production method utilizing a coupling reaction of a dihalogenosilane using an alkali metal.

Since the polysilane obtained by this production method is a mixture of a cyclic polymer and a polymer having a terminal of a halogen atom or a hydrogen atom, it is difficult to quantitatively obtain a polymer whose terminal is modified from this mixture. .

Regarding the synthesis of the polysilane modified at one end, living polymerization from a polymer containing a disilane unit has been studied by Sakurai et al. In addition to introducing hydrogen and carboxylic acid, PMMA (polymethylmethacrylate) has been introduced. ) Has been reported (Chemicals and Industry, Vol. 42, No. 4, p. 744).

However, this manufacturing method has some problems in industrialization, such as limited substituents and difficulty in obtaining monomers.

Regarding both-end or one-end-reactive polysilanes, see “Journal of Organometallic Chemistry, Vol. 2, p474-484 (196).
4) ”,“ Journal of Organometallic Chemistry, Vol. 23, p63-69 (197).
0) ”, a terminal chlorooligosilane is obtained by reacting permethyloligosilane with acetyl chloride in the presence of aluminum chloride, and a terminal phenyloligosilane is treated with hydrogen chloride or chlorosilane in the presence of aluminum chloride. The terminal chlorooligosilane can be obtained by the reaction. However, the terminal chloropolysilane obtained by this production method has a low degree of polymerization.

The present invention has been made in view of the above circumstances,
The degree of polymerization is large, various functional groups can be introduced, and both-terminal chloropolysilane suitable as a raw material for producing a copolymer with another polymer and both-terminal chloropolysilane can be easily produced. It is intended to provide a manufacturing method.

[0008]

Means and Actions for Solving the Problems As a result of earnest studies for achieving the above-mentioned object, the present inventor found that "Applied Organometallic Chemistry, Vol.
p7-14 (1987) ", focusing on the reaction that polysilane has a low molecular weight due to the formation of highly reactive silylene and silyl radicals from polysilane decomposed by ultraviolet rays, a chlorinated hydrocarbon as a solvent that easily extracts chlorine. It was found that by irradiating a high molecular weight polysilane with ultraviolet rays in this chlorinated hydrocarbon and photodecomposing it, chloro radicals having a large degree of polymerization can be obtained by the generated silyl radicals.

That is, the high molecular weight polysilane obtained by the coupling reaction of dichlorosilane with an alkali metal is a mixture of a cyclic polymer and a polymer having a chlorine atom or a hydrogen atom at the end. When irradiated, the cyclic polymer opens at the same time by photolysis to become chloropolysilanes at both ends,
Further, when the terminal is a halogen atom, it does not react, but when the terminal is a hydrogen atom, the hydrogen atom is replaced by a chlorine atom by light or heat, and as a result, a high molecular weight polysilane is reduced in both molecular weight chloropolysilane at both ends. It was discovered that the molecular weight at this time was dependent on the irradiation dose of ultraviolet rays, and the present invention was completed.

Therefore, the present invention is characterized by being represented by the following formula (1):

[0011]

[Chemical 2] (In the formula, R ¹ , R ² , R ³ and R ⁴ have the same or different carbon number 1
To 12 alkyl groups or substituted or unsubstituted aryl groups, n, m, and k are 0 ≦ n ≦ 10, 0 ≦ m ≦ 10, n + m
It is a number that satisfies ≧ 10 and k ≧ 1. ) And irradiating a chlorinated hydrocarbon solution of a high molecular weight polysilane with an ultraviolet ray in an inert gas atmosphere, there is provided a method for producing chloropolysilane having both terminals.

The present invention will be described in more detail below. The chloropolysilane having both ends at the present invention is represented by the following formula (1).

[0013]

[Chemical 3]

Here, R ¹ , R ² , R ³ and R ⁴ are the same or different C1 to C12, preferably C1 to C10 alkyl groups or substituted or unsubstituted aryl groups. Specific examples of the group include a methyl group, ethyl group and propyl group, and examples of the aryl group include a phenyl group and a tolyl group. n, m, and k are 0 ≦ n ≦ 10,0
It is a number that satisfies ≦ m ≦ 10, n + m ≧ 10, and k ≧ 1, but in order to show the properties of polysilane such as photoconductivity, k is
Is preferably 5 or more, and particularly preferably 10 or more.

In order to obtain the chloropolysilane having terminals at both ends represented by the above formula (1), first, polysilane is synthesized by a coupling reaction of dichlorosilane with an alkali metal such as sodium. In this case, dichlorosilanes other than dimethyldichlorosilane alone are used, and aromatic group-containing dichlorosilanes such as methylphenyldichlorosilane, ethylphenyldichlorosilane, etc., and dichlorosilanes containing C ₂ or more aliphatic groups. For example, methylethyldichlorosilane, methylpropyldichlorosilane, methylhexyldichlorosilane, dihexyldichlorosilane and the like can be used alone or in combination of two or more kinds.

The number average molecular weight (M
n) is preferably 1,000 or more.

The method for producing chloropolysilane having both terminals at the end of the present invention is to dissolve the polysilane thus obtained, which is generally represented by the following formula (2), in a chlorinated hydrocarbon solution, and subject it to ultraviolet light in an inert gas atmosphere. To irradiate.

[0018]

[Chemical 4] (In the formula, R ¹ , R ² , R ³ and R ⁴ have the same meanings as described above, and n ′ and m ′ are each 0 or more and 1 ≦ n ′ + m ′.)

Here, examples of the chlorinated hydrocarbon include dichloromethane, chloroform, carbon tetrachloride, and 1,2-
Dichloroethane, 1,1,2-trichloroethane, 1,
1,2,2-tetrachloroethane and the like can be mentioned, and one of these can be used alone or two or more can be used in combination.

When polysilane is dissolved in chlorinated hydrocarbon, the concentration of the solution is preferably 1 to 20% (weight%, the same hereinafter), and particularly preferably 1 to 10%. Enclose this polysilane solution in a Pyrex reaction tube or quartz tube,
Ultraviolet rays are radiated using a high pressure mercury lamp (312 nm) in an inert gas atmosphere. In this case, nitrogen gas, argon gas or the like can be used as the inert gas. Further, the ultraviolet irradiation dose can be arbitrarily selected, and the molecular weight of the resulting chloropolysilane having both terminals is dependent on the ultraviolet irradiation dose.

After irradiating a predetermined amount of ultraviolet rays, the reaction solution was concentrated to 1/2 to ⅕, and about 150 g of hexane was added to about 10 g of polysilane to add chloropolysilane having both ends (Mn ≧ 1). , 000) is precipitated, and then filtered and dried to obtain the target chloropolysilane having both terminals as a white powder.

The thus-obtained chloropolysilane having both terminals at the both ends of the present invention has reactive chlorine at both terminals, so that a hydroxyl group is introduced at both terminals by a method such as hydrolysis, and further hydroxyl groups at both terminals are introduced. A polysilane can be used to obtain a dialkylhydroxypolysilane having both ends and a dialkylvinylsiloxypolysilane having both ends, and can be used as a raw material for a copolymer with another polymer.

[0023]

EXAMPLES The present invention will be specifically described below with reference to examples, but the present invention is not limited to the following examples.

Examples 1 to 5 Methylphenylpolysilane (Mn = 24.0) obtained by the coupling reaction of methylphenyldichlorosilane with sodium.
0, Mw / Mn = 3.32) 7.0 g was added to carbon tetrachloride 13
It was dissolved in 3 g and the concentration was adjusted to 5%. In a nitrogen gas atmosphere, the polysilane solution was sealed in a Pyrex reaction tube with a diameter of 15 mm, and ultraviolet rays (312 m
m) was irradiated at 1 J / cm ² . After concentrating the reaction solution to about 50 g, 100 g of hexane was added to precipitate chloropolysilane having both terminals represented by the following formula (3),
A white powder was obtained by filtration and drying (Example 1).

The dose of ultraviolet rays is ² J / cm ² , 3 J / c
White powder was obtained in the same manner as in Example 1 except that m ² , 5 J / cm ² , and 10 J / cm ² were used (Examples 2 to 5).

Table 1 shows the measurement results of the obtained white powder.

[0027]

[Chemical 5]

[0028]

[Table 1]

Example 6 Methylphenylpolysilane obtained by the coupling reaction of methylphenyldichlorosilane and sodium (Mn = 15,900, Mw / M)
0.5 g of n = 10) was dissolved in 9.5 g of dichloromethane to adjust the concentration to 5%. Diameter 1 under nitrogen gas atmosphere
A 5 mm Pyrex reaction tube was filled with a polysilane solution, and a high pressure mercury lamp was used to emit ultraviolet rays (312 nm) at a level of 0.
Irradiation was performed at 5 J / cm ² . After concentrating the reaction solution to about 2 g, 20 g of hexane was added to precipitate the target substance,
By filtration and drying, chloropolysilane having both terminals was obtained as a white powder.

[Embodiment 7] The irradiation amount of ultraviolet rays is 1 J / cm.
^A white powder was obtained in the same manner as in Example 6 except that the number was changed to ² .

Example 8 Methylphenylpolysilane obtained by the coupling reaction of methylphenyldichlorosilane and sodium (Mn = 15,900, Mw / M)
n = 10) 0.5 g to 1,2-dichloroethane 9.5 g
Was dissolved in the solution and the concentration was adjusted to 5%. Under nitrogen gas atmosphere,
The Pyrex reaction tube having a diameter of 15 mm was filled with the polysilane solution and irradiated with ultraviolet rays (312 nm) at 0.5 J / cm ² using a high pressure mercury lamp. After concentrating the reaction solution to about 2 g, 20 g of hexane was added to precipitate the desired product, and chloropolysilane having both terminals was obtained as a white powder by filtration and drying.

[Embodiment 9] The irradiation amount of ultraviolet rays is 1.5 J /
A white powder was obtained in the same manner as in Example 8 except that cm ² was used.

[Examples 10 to 12] Solvents were chloroform, 1,1,2-trichloroethane and 1,1, respectively.
Chloropolysilane having both terminals was obtained as a white powder in the same manner as in Example 6 except that 2,2-tetrachloroethane was used.

Table 2 shows the measurement results of the molecular weight and the chlorine content of the chloropolysilanes having terminals at both ends obtained in Examples 6 to 12.

[0035]

[Table 2] * Polystyrene conversion

Next, a description will be given of an example of producing a hydroxypolysilane having both terminals at the end, which is synthesized by using the chloropolysilane having both terminals at the present invention.

[Reference Example 1] 5.0 g (Mn = 7,500, Mw / Mn =) of chloromethylphenylpolysilane at both ends
1.57) was dissolved in 100 g of THF, 0.2 g of triethylamine was added, 3 g of water was added dropwise, and the mixture was stirred under reflux for 4 hours. After the completion of the reaction, 100 g of toluene was added, washing with 100 g of water was performed 3 times, and the organic layer was dried over calcium chloride overnight. After filtering off the desiccant, concentration was carried out to obtain 3.5 g of white powder.

The measurement results of the obtained white powder are shown below. From this result, it is found that the obtained white powder is hydroxymethylphenylpolysilane having both terminals.

Yield: about 75% Mn: 7,550 (in terms of polystyrene) Mw / Mn: 1.64 IR analysis: 3624 cm ⁻¹ (Si—OH) peak confirmation OH amount: 0.0260 mol / 100 g
(Calculated value 0.0265 mol / 100 g)

Reference Example 2 15.0 g (Mn = 5,600, Mw / Mn) of chloromethylphenylpolysilane at both ends
= 1.66) was dissolved in 300 g of THF, 1.2 g of triethylamine was added, 10 g of water was added dropwise, and the mixture was stirred under reflux for 4 hours. After completion of the reaction, 300 g of toluene was added, and washing with 300 g of water was performed 3 times, and the organic layer was dried over calcium chloride overnight. After filtering off the desiccant, concentration was carried out to obtain 11.3 g of white powder.

The measurement results of the obtained white powder are shown below. From this result, it is found that the obtained white powder is hydroxymethylphenylpolysilane having both terminals.

Yield: About 75% Mn: 5,620 (in terms of polystyrene) Mw / Mn: 2.09 IR analysis: 3624 cm ⁻¹ (Si—OH) peak confirmation OH amount: 0.0350 mol / 100 g
(Calculated value 0.0356 mol / 100 g)

[0043]

EFFECTS OF THE INVENTION According to the present invention, both-end chloropolysilane having a degree of polymerization of 5 or more, particularly 10 or more can be easily synthesized, and various functional groups are introduced into the obtained both-end chloropolysilane. In addition, it can be preferably used as a raw material for producing a copolymer with another polymer.

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

Claims (2)

[Claims] 1. A both-terminal chloropolysilane represented by the following formula (1): [Chemical 1] (In the formula, R ¹ , R ² , R ³ and R ⁴ have the same or different carbon number 1
To 12 alkyl groups or substituted or unsubstituted aryl groups, n, m, and k are 0 ≦ n ≦ 10, 0 ≦ m ≦ 10, n + m
It is a number that satisfies ≧ 10 and k ≧ 1. ) 2. A method for producing chloropolysilane having both terminals, which comprises irradiating a chlorinated hydrocarbon solution of a high molecular weight polysilane with ultraviolet rays in an inert gas atmosphere.