JPH0762105A - Fullerene-organosilane copolymer - Google Patents

Abstract

PURPOSE:To allow patterning with fullerene's optical functions by producing the title compound, soluble in THF, processable into films, and having the structure of a copolymer of a fullerene and a specific organosilane compound, the optical functions being exhibited by photosensitivity of the film. CONSTITUTION:A fullerene, such as C60 or C70, and an alkali metal are treated with ultrasonic waves after being dispersed in tetrahydrofuran to be mixed with each other, or treated by constant-potential electrolysis with an electrolyte and platinum electrodes, the electrolyte consisting of methylene chloride as the supporting salt, (C4H9)4NPF6 as the solvent and fullerene, to produce a fullerene anion. A divalent fullerene is preferable. The most preferable fullerene to alkali ratio is 1/2 mol/mol for the former method, and the most preferable potential for the latter method is intermediate between the divalent and trivalent redox potentials. This solution is polymerized with a dihaloorganosilane compound added dropwise, which compound has hydrocarbon groups directly bonded to Si and an Si to hydrocarbon ratio of 1/2, to produce a fullerene-organosilane copolymer represented by the formula wherein R1 represents a fullerene group; R2 and R3 represent each a hydrocarbon group; and n is preferably 1 to 20.

Description

Detailed Description of the Invention

[0001]

FIELD OF THE INVENTION The present invention relates to a fullerene-organosilane copolymer.

[0002]

2. Description of the Related Art Fullerenes represented by C ₆₀ have been attracting attention as new functional materials in recent years because they have optical and electrical properties due to their special electronic system. If it can be formed into a pattern having different physical properties such as electrical properties, it can be expected to be applied to an optical waveguide or a semiconductor circuit.

However, fullerenes are mainly limited to non-polar solvents such as toluene as a solvent showing good solubility. Further, since fullerenes exist as powders, the film forming method is limited to the vapor deposition method and the like, and there is a problem in film forming property.

In order to solve this problem, a fullerene-containing polymer having a repeating unit represented by the following chemical formula (6), that is, a polyamide having a fullerene skeleton in its side chain has been synthesized (J. Am. Chem. Soc). .1992,114,10656-10
657), such a polymer has improved film forming properties. However, in order to realize an optical element, an electric element, or the like that fully exerts the function of the fullerene as described above, it is necessary to pattern the obtained film into a desired shape to obtain optical and electric properties. It is necessary to form patterns with different physical properties. From such a viewpoint, in a film formed using the polyamide, it is difficult to form patterns having different physical properties, and therefore, an optical element, an electric element, or the like that fully exerts the function of fullerene is realized. Was not enough for.

[0005]

[Chemical 1]

[0006]

As described above, in the conventional fullerene-containing polymer, although the film forming property is good, it is difficult to form a pattern having different physical properties on the film obtained after the film formation. Therefore, it is still insufficient to realize an optical element, an electric element, or the like that fully exerts the function of fullerene. The present invention solves such problems and provides a photosensitive fullerene-organosilane copolymer capable of forming a pattern having different physical properties in a film obtained by using a fullerene-containing polymer in a simple process. With the goal.

[0007]

The present invention has a silicon atom and a substituted or unsubstituted hydrocarbon group directly bonded to the silicon atom, and the silicon atom / hydrocarbon group ratio is 1 / It is a fullerene-organosilane copolymer having a copolymer structure of the organosilane compound of 2 and fullerene.

The present invention will be described in detail below. The fullerene-organosilane copolymer in the present invention is more specifically a polymer having a repeating unit represented by the following general formula (1).

[0009]

[Chemical 2]

This fullerene-organosilane copolymer produces, for example, anions of fullerenes, and Cl, Br, I in which the anions of fullerenes and silicon atoms are bonded.
Can be obtained by polymerizing a dihaloorganosilane compound having a halogen atom such as

The above-mentioned fullerenes include C ₆₀ , C ₇₀ and C
_There is no particular limitation as long as it is ₇₂ fullerenes, and these may be used alone or in admixture of two or more. The fullerene anions can be produced by two methods, that is, a method using ultrasonic treatment and a method of performing potentiolytic decomposition.

First, in the method using ultrasonic treatment, fullerene and an alkali metal are dispersed and mixed in a solvent of THF (tetrahydrofuran), and then ultrasonic treatment is carried out at a reaction temperature of −90 to 200 ° C. for 0.5. The anion of the fullerene is generated by performing the treatment for not less than an hour, more preferably at 0 to 50 ° C. for not less than 2 hours.

Considering synthesizing a linear fullerene-organosilane copolymer, it is preferable to generate anions of divalent fullerenes. For this reason,
The molar ratio of fullerene to alkali metal is 1: 0.
The ratio is preferably 8 to 30, more preferably 1: 1.8 to 4, and most preferably 1: 2 in consideration of the yield. Also, the reaction time is preferably set appropriately according to the particle size of the alkali metal used.

On the other hand, in the method of performing potentiostatic decomposition,
Anions of fullerenes are generated near the electrode on the reduction side by subjecting the electrolytic solution obtained by dissolving the fullerenes and the supporting salt in a solvent to potentiostatic decomposition. As the supporting salt at this time, it is inactive at the electrolysis potential when performing potentiostatic decomposition, does not react with the anions of fullerenes, and an amount sufficient to give the necessary conductivity to the electrolytic solution is the solvent. A compound soluble in water is used.

The solvent must be one that dissolves fullerenes and fullerene anions to some extent. The electrode used in the constant potential electrolysis is not particularly limited, but as the reduction-side electrode, a conductive substance that is difficult to react at the constant potential is used to prevent the reacted electrode from mixing as an impurity in the electrolytic solution. It is preferable to use. On the other hand, for the electrode on the oxidation side, it is desirable to use a reactive electrode such as aluminum in order to activate the electrolytic reaction. Further, since the impurities generated on the oxidation side are not mixed with the anions of the fullerenes, the oxidation side and the reduction side may be separated by a glass filter or the like. Specifically, the following combinations are preferable as the supporting salt, the solvent, and the reducing-side electrode.

[0016]

[Table 1]

The electrolytic potential varies depending on the solvent and supporting salt used in the electrolytic solution, but as described above, since the anion of the divalent fullerene is desired, it is lower than the divalent redox potential and is trivalent. It is desirable to be higher than the redox potential of.

As described above, in the present invention, anions of fullerenes are usually produced in a solution by these methods. Further, as the dihaloorganosilane compound,
The number of silicon atoms and the like are not particularly limited as long as the silicon atom is bonded to a substituted or unsubstituted hydrocarbon group in addition to the halogen atom as described above. However, when the dihaloorganosilane compound is a polymer having a high degree of polymerization, the fullerene-organosilane copolymer to be synthesized may have poor fullerene properties. Therefore, the number of Si in the main chain is preferably 1 or less. 30 or more
The number is less than or equal to 1, more preferably 1 or more and 20 or less.

The hydrocarbon group has 6 to 14 carbon atoms.
The aryl group or the alkyl group having 1 to 4 carbon atoms is preferable. This is because if the molecular weight of the hydrocarbon group becomes large, steric hindrance may occur and the degree of polymerization of the synthesized fullerene-organosilane copolymer may not be sufficiently increased.

The dihalooligosilane having a plurality of silicon atoms is, for example, 1,3-dichloro-1,1,2,
In the case of 2,3,3-hexaalkyltrisilane, 1,3-diphenyl-1,1, is obtained by reacting dichlorodialkylsilane with 2 equivalents of phenyldialkylsilyllithium.
It can be obtained by synthesizing 2,2,3,3-hexaalkyltrisilane and then substituting the phenyl group with the chloro group by a suitable acid catalyst. Further, instead of the dichlorodialkylsilane, the obtained 1,3-
By using dichloro-1,1,2,2,3,3-hexaalkyltrisilane, 1,5-dichloro-1,
1,2,2,3,3,4,4,5,5-octalkylpentasilane can be obtained. In this way, the desired dihaloorganosilane compound can be obtained. Further, in the present invention, such dihaloorganosilane compounds may be used alone or in combination of two or more.

In the present invention, the solution of the dihaloorganosilane compound is added dropwise to the solution containing the anion of the fullerene obtained as described above to cause a polymerization reaction, and the fullerene-organosilane compound of the present invention is added. A polymer is synthesized. At this time, the compounding ratio of the fullerene and the dihaloorganosilane compound is 1: 0.5 to 2.
0 or even 1: 0.8 to 1.2, most preferably 1: 1. This is because if the compounding ratio is extremely different, the degree of polymerization of the fullerene-organosilane copolymer to be synthesized may not be sufficiently increased.

After the polymerization reaction, it is desirable to cap the remaining reaction active site. At this time, trimethylchlorosilane having one reaction active site may be used.

When the solution containing the fullerene-organosilane copolymer synthesized after this is subjected to ultrasonic treatment as described above, unnecessary substances such as alkali metals are filtered out, and potentiostatic electrolysis is performed. Is distilled off the solvent and extracted with a solvent capable of dissolving the obtained polymer such as toluene. Then, the filtrate or extract is concentrated under reduced pressure, the concentrated solution is reprecipitated, and the precipitate is filtered off and dried under vacuum to have the repeating unit represented by the general formula (1), The fullerene-organosilane copolymer of the present invention in which fullerene and organosilane are alternately bonded can be obtained.

The preferred molecular weight of the fullerene-organosilane copolymer of the present invention is preferably 1,500 20,000,000, more preferably 5,000 200,000. This is because if the molecular weight is small, the properties as a polymer cannot be sufficiently exhibited, and if the molecular weight is too large, the solubility in a solvent may decrease.

The fullerene-organosilane copolymer of the present invention has a high solubility in THF and the like, and can be easily formed into a film by applying it as a THF solution to a substrate and drying it.

Further, the fullerene-organosilane copolymer of the present invention has a function as a photosensitive resin because it has a silicon atom in the main chain. Therefore, as described above, by forming a film on the substrate and then exposing it with an exposure device,
It becomes possible to form desired patterns having different physical properties. That is, after the fullerene organosilane copolymer composition film of the present invention, when exposed through a mask having a desired pattern, the organosilane skeleton is oxidized in the exposed portion to generate an organosiloxane skeleton, and thus, for example, electric conductivity or It is fully expected to realize optical fibers and optical computers that can form patterns with different physical properties such as refractive index and that exhibit the optical functions of fullerenes.

[0027]

【Example】

Example 1 12 mg of metallic lithium was dispersed in 10 ml of THF to prepare a dispersion liquid, 500 mg of C ₆₀ was added to the dispersion liquid, and ultrasonic treatment was performed in the atmosphere at 15 ° C. for 5 hours.

A solution prepared by dissolving 125 mg of 1,2-dichloro-1,2-dimethyl-1,2-diphenyldisilane in 3 ml of THF was added dropwise to the ultrasonically treated dispersion liquid,
The reaction was continued for 10 hours. Subsequently, 0.3 g of trimethylchlorosilane was added and the reaction was continued for another 1 hour.

After the reaction was completed, unreacted lithium and unnecessary substances such as lithium chloride were filtered off, and the filtrate was concentrated under reduced pressure. Next, this concentrated solution is poured into methanol to precipitate the formed polymer, and then the precipitate is filtered off and dried under vacuum to obtain the fullerene-organosilane of the present invention having a repeating unit represented by the following chemical formula (2). A copolymer was obtained (yield 3%, average molecular weight 10,000). The peaks of the IR and NMR spectra of the obtained polymer are shown below.

[0030]

[Chemical 3] IR (KBr, cm ^-1 ) 2965 (m), 2869
(M), 1432 (s), 1282 (w), 700
(M), 572 (m), 522 (m) 1H NMR (270 MHz, C ₆ D ₆ ) δ −
0.3-1.2 (b), 6.5-7.8 (b) Next, the obtained fullerene-organosilane copolymer was dissolved in THF to prepare a 1 wt% THF solution, This solution was spin-coated on a glass substrate at a rotation speed of 1500 rpm to form a film of fullerene-organosilane copolymer having a film thickness of 50 nm.

A high pressure mercury lamp with an output of 7 mW / cm ² was used for the film of this fullerene-organosilane copolymer.
As a result of time exposure, the infrared absorption spectrum of the exposed part showed an increase in absorption at around 1100 cm ⁻¹ compared to the unexposed part, and the organosilane skeleton was oxidized by the exposure to form an organosiloxane skeleton. I knew that.
Further, as a result of measuring the refractive index of each of the exposed portion and the unexposed portion, a pattern having different physical properties is formed, such as 1.59 in the unexposed portion and 1.31 in the exposed portion, which is applicable to, for example, an optical waveguide. I was able to confirm that.

Further, after the formation of this pattern, the unexposed portion was dissolved and removed by washing with toluene, and it was possible to perform patterning into a desired shape. When the obtained pattern shape was observed with a microscope, it was 100 μm.
m lines and spaces were resolved and had sufficient resolution.

This is because the polysilane has a phenyl group and a methyl group in the side chain of silicon so that the polysilane having a phenyl group and a methyl group is crosslinked by light irradiation in the fullerene-organosilane copolymer of the present invention. Also, in the case of a methyl group, since it is cross-linked by irradiation with light, it is considered that only the exposed portion becomes insoluble in toluene as described above.

Separately from the pattern formation, pellets having a thickness of 0.1 mm were formed from the fullerene-organosilane copolymer of this example by a pressure molding machine. The pellets were washed with AsF ₅ at room temperature and a pressure of 450 torr for 5 hours.
After exposure to steam, gold was vapor-deposited on the upper and lower electrodes, and the electrical conductivity was measured according to the method described in the Handbook of Insulation Test Method (ed. As a result, 5 × 10 ⁻⁶ s · cm ⁻¹
It has been found that the pattern having the desired shape obtained by the above-mentioned method and having the desired shape can be sufficiently applied to, for example, a semiconductor circuit.

Example 2 30 mg of C ₆₀ was added to a solution of 620 mg of tetrabutylammonium perchlorate dissolved in 30 ml of methylene chloride,
Using glassy carbon on the reducing side and aluminum on the oxidizing side as electrodes, electrolysis was performed at -1.2 V (voltage lower than divalent redox potential and higher than trivalent redox potential) for 7 hours. At this time, both electrodes were separated by a glass filter.

After electrolysis, a solution prepared by dissolving 10 mg of 1,2-dichloro-1,1,2,2-tetrabutyldisilane in 1 ml of THF was added dropwise to the obtained electrolytic solution, and the mixture was reacted at 15 ° C. for 5 hours and then toluene was added. It was extracted with. The extract was concentrated under reduced pressure, the concentrate was poured into ethanol to precipitate the synthesized fullerene-organosilane copolymer, the precipitate was filtered off and dried under vacuum, and the chemical formula (3) below was used. A fullerene-organosilane copolymer of the present invention having a repeating unit represented by the following formula was obtained (yield 3%, average molecular weight 15,000).
0). The peaks of the IR and NMR spectra of the obtained polymer are shown below.

[0037]

[Chemical 4] IR (KBr, cm ^-1 ) 2935 (s), 2870
(S), 1430 (m), 1244 (s), 856
(S), 572 (s), 522 (m) ¹ HNMR (270 MHz, C ₆ D ₆ ) δ 0.6
-1.1 (b), 1.2-1.6 (b) Next, the obtained fullerene-organosilane copolymer was dissolved in THF to prepare a 1 wt% THF solution, and this solution was A glass substrate was spin-coated at a rotation speed of 1500 rpm to form a fullerene-organosilane copolymer film having a film thickness of 50 nm.

Further, the fullerene-organosilane copolymer film was exposed to light for 1 hour using a high pressure mercury lamp having an output of 7 mW / cm ² , and the infrared absorption spectrum of the exposed part was compared with that of the unexposed part. It was found that the absorption around 1100 cm ⁻¹ was increased, and that the organosilane skeleton was oxidized by exposure to form an organosiloxane skeleton. Further, as a result of measuring the refractive index of each of the exposed portion and the unexposed portion, 1.57 in the unexposed portion and 1.3 in the exposed portion.
5, it was confirmed that patterns having different physical properties were formed as in Example 1.

Example 3 As in Example 1, 12 mg of metallic lithium was added to 10 m of THF.
1 to prepare a dispersion liquid, and to this dispersion liquid, C ₆₀ 50
0 mg was added, and the mixture was sonicated in the atmosphere at 15 ° C. for 5 hours.

130 m of 1,2-dichloro-1,1,2,2-tetrabutyldisilane was added to this ultrasonically treated dispersion.
a solution prepared by dissolving 3 g of THF in 3 ml of THF was added dropwise, and further 1
The reaction was allowed for 0 hours. Then trimethylchlorosilane 0.
3g was added and it was made to react for 1 hour.

After completion of the reaction, unreacted lithium and unnecessary substances such as lithium chloride were filtered off, and the filtrate was concentrated under reduced pressure. Next, this concentrated solution is poured into ethanol to precipitate the produced polymer, and the precipitate is filtered off and dried under vacuum to obtain the fullerene-organosilane of the present invention having the repeating unit represented by the above chemical formula (3). A copolymer was obtained (yield 7%, average molecular weight 11,000). The peaks of the IR and NMR spectra of the obtained polymer are shown below. IR (KBr, cm ^-1 ) 2935 (s), 2870
(S), 1244 (s), 856 (s), 572
(S), 522 (m) 1H NMR (270 MHz, C ₆ D ₆ ) δ 0.
1 (s), 0.6-1.1 (b), 1.2-1.6
(B) Next, the obtained fullerene-organosilane copolymer was dissolved in THF to prepare a 1% toluene solution, and this solution was spin-coated on a glass substrate at a rotation speed of 1500 rpm to give a film thickness of 5
A 0 nm fullerene-organosilane copolymer film was deposited.

Further, the fullerene-organosilane copolymer film was exposed to light for 1 hour using a high pressure mercury lamp having an output of 7 mW / cm ² , and the infrared absorption spectrum of the exposed part was compared with that of the unexposed part. It was found that the absorption around 1100 cm ⁻¹ was increased, and the organosilane skeleton was oxidized by the exposure to form an organosiloxane skeleton. Further, as a result of measuring the refractive index of each of the exposed portion and the unexposed portion, 1.57 in the unexposed portion and 1.35 in the exposed portion.
It was confirmed that a pattern having different physical properties was formed as in Example 1.

1,2-dichloro-1,1,2,2-
Instead of 130 mg of tetrabutyldisilane, 1,3-
Except for using 160 mg of dichloro-1,1,2,2,3,3-hexabutyltrisilane, the fullerene-organosilane copolymerization of the present invention having the repeating unit represented by the following chemical formula (4) was performed in exactly the same manner. A coalescence was obtained (yield 3%, average molecular weight 1,2000). The peaks of the IR and NMR spectra of the obtained polymer are shown below.

[0044]

[Chemical 5] 1H NMR (KBr, cm ⁻¹ ) 2935 (s), 2
865 (s), 1428 (m), 1250 (s), 85
7 (s), 572 (s), 522 (m) 1H NMR (270 MHz, C ₆ D ₆ ) δ 0.
1 (s), 0.5-1.2 (b), 1.2-1.8
(B) Example 4 In the same manner as in Example 1, 12 mg of metallic lithium was added to 10 m of THF.
1 to prepare a dispersion liquid, and to this dispersion liquid, C ₆₀ 50
0 mg was added, and the mixture was sonicated in the atmosphere at 15 ° C. for 5 hours.

A solution prepared by dissolving 140 mg of 1,2-dichloro-1,1,2-tributyl-2-phenyldisilane in 3 ml of THF was added dropwise to this ultrasonically treated dispersion liquid,
The reaction was continued for 10 hours. Subsequently, 0.3 g of trimethylchlorosilane was added, and the reaction was further performed for 1 hour.

After completion of the reaction, unreacted lithium and unnecessary substances such as lithium chloride were filtered off, and the filtrate was concentrated under reduced pressure. Next, this concentrated solution is poured into methanol to precipitate the formed polymer, and the precipitate is filtered off and dried under vacuum to obtain the fullerene-organosilane of the present invention having a repeating unit represented by the following chemical formula (5). A copolymer was obtained (yield 5%, average molecular weight 11,000). The peaks of the IR and NMR spectra of the obtained polymer are shown below.

[0047]

[Chemical 6] 1H NMR (KBr, cm ⁻¹ ) 3060 (m), 3
040 (m), 2950 (s), 2925 (s), 14
20 (s), 1244 (s), 734 (m), 700
(S), 572 (s), 522 (m) 1H NMR (270 MHz, C ₆ D ₆ ) δ −
0.3-1.2 (b), 6.5-7.8 (b) Next, the obtained fullerene-organosilane copolymer was dissolved in THF to prepare a 1% toluene solution. The solution was spin-coated on a glass substrate at a rotation speed of 1500 rpm to give a film thickness of 5
A 0 nm fullerene-organosilane copolymer film was deposited.

Further, the fullerene-organosilane copolymer film was exposed to light for 1 hour using a high pressure mercury lamp with an output of 7 mW / cm ² , and the infrared absorption spectrum of the exposed part was compared with that of the unexposed part. It was found that the absorption around 1100 cm ⁻¹ was increased, and the organosilane skeleton was oxidized by the exposure to form an organosiloxane skeleton. Further, as a result of measuring the refractive index of each of the exposed portion and the unexposed portion, 1.60 in the unexposed portion and 1.31 in the exposed portion.
It was confirmed that a pattern having different physical properties was formed as in Example 1.

[0049]

As described above, the fullerene of the present invention
Since the organosilane copolymer has photosensitivity, it is possible to form desired film patterns having different physical properties on the obtained film by a simple process.

 ─────────────────────────────────────────────────── ─── Continuation of front page (72) Inventor Shuji Hayase 1 Komukai Toshiba-cho, Sachi-ku, Kawasaki-shi, Kanagawa Incorporated Toshiba Research and Development Center

Claims (1)

[Claims] 1. An organosilane compound having a silicon atom and a substituted or unsubstituted hydrocarbon group directly bonded to the silicon atom, wherein the silicon atom / hydrocarbon group ratio is 1/2, and fullerene. A fullerene-organosilane copolymer having a copolymer structure of