JPH0959355A - Multi-branched polymer and its production - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain a multi-branched polymer composed of a specific recurring unit, exhibiting a high solubility without introducing a substituent, having excellent film-forming property and capable of giving an electrically conductive polymer film by doping a film of the polymer with an electron-accepting reagent, etc. SOLUTION: This polymer is composed of the recurring unit of formula I or formula II. It can be produced e.g. by dropping a hexane solution of n- butyllithium to a tetrahydrofuran solution of 1,3.5-tris(p-halogenophenyl)benzene or 1,3,5-tris(5'-halogeno-2'-thienyl)benzene at -78 deg.C, dropping an ether solution of a halogenated magnesium etherate to the obtained reaction liquid to obtain a solution containing a compound of formula III or formula IV, dropping the obtained solution to a tetrahydrofuran solution of nickel acetylacetonate and polymerizing the components by Grignard reaction under refluxing.

Description

Detailed Description of the Invention

[0001]

TECHNICAL FIELD The present invention relates to a hyperbranched polymer and a method for producing the same, and more particularly to a soluble polymer and a method for producing the same.

[0002]

2. Description of the Related Art Polymers having a π-conjugated system as a skeleton
It is known that conductivity is exhibited by doping an electron-accepting or electron-donating reagent. Such polymers, called conductive polymers, can be used in batteries, semiconductor devices,
It has attracted attention as a conductive material used for light emitting devices and the like. However, such a high-molecular polymer has insolubility and infusibility and thus is inferior in processability, and it is difficult to apply it to an actual device. For example, a linear high molecular polymer using a π-conjugated skeleton of a thiophene ring or a benzene ring is hardly soluble in an organic solvent.

It is known that the solubility is improved by introducing a substituent such as an alkyl group.

[0004]

In order to improve the solubility of a conductive polymer having a linear conjugated chain in an organic solvent by the conventional method, it is necessary to introduce a substituent such as an alkyl group. is there. However, the molecular structure is regulated by introducing a substituent that does not participate in conductivity.

An object of the present invention is to provide a technique for obtaining a highly soluble polymer without introducing a substituent.

[0006]

According to one aspect of the present invention, a general formula

[0007]

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There is provided a polymer comprising a repeating unit represented by: This polymer is soluble in tetrahydrofuran. A polymer film can be produced by coating a glass substrate with a solution prepared by dissolving a polymer in tetrahydrofuran and drying the solution.

According to another aspect of the invention, the general formula

[0010]

[Chemical 6]

There is provided a conductive polymer in which a polymer having a repeating unit represented by the formula (3) is doped with an electron-accepting reagent to impart conductivity. According to another aspect of the invention, a general formula

[0012]

[Chemical 7]

There is provided a method for producing a polymer, which comprises a step of polymerizing a compound represented by the formula (1) by a Grignard reaction. The polymer obtained by this method has a high degree of branching and 3
It has a dimensional spread. It is also soluble in tetrahydrofuran.

[0014]

BEST MODE FOR CARRYING OUT THE INVENTION A first embodiment of the present invention will be described with reference to FIGS. First, a method for producing 1,3,5-tris (p-bromophenyl) benzene which is a raw material of a polymer will be described. The manufacturing method described below is based on Young H. Kim and Richard Beckerbauer (Macromolecules 1994, 2
7 , 1968-1971).

14.40 g (72.3 mmol) of p-
70 ml of toluene was added to bromoacetophenone and dissolved. 0.1 ml of trifluoromethanesulfonic acid was added as a catalyst, and the reaction was carried out under reflux in the reaction vessel. The water generated during the reaction was removed by a Dean Stark type water trap. After refluxing for 17 hours, the reaction solution was cooled to room temperature, whereby an orange precipitate was generated.

After further concentrating, the precipitate was separated by filtration, washed with toluene, and dried under vacuum at 55 ° C. for 3 hours. Weight 8.87g
(Yield 66.3%) yellow needle crystals were obtained. The melting point of needle crystals is 265 to 268 ° C. (literature values 259 to 261).
℃).

FIG. 1 shows an ultraviolet-visible absorption spectrum of the obtained needle crystal. The horizontal axis represents the wavelength in the unit of nm, and the vertical axis represents the molar extinction coefficient in the unit of mM ⁻¹ cm ⁻¹ . Wavelength 263
Absorption due to π-π ^* transition is observed at nm.
The molar extinction coefficient at this time was 78 mM ⁻¹ cm ⁻¹ .

FIG. 2 shows an infrared absorption spectrum of the obtained needle crystal. The horizontal axis represents the wave number in units of cm ⁻¹ , and the vertical axis represents the transmittance in units of%. Wave number 810 cm ^-1 , 888 cm
Characteristic absorption peaks appear at ^-1 , 1008 cm ^-1 , and 1490 cm ^-1 . Absorption peak at a wavenumber of 810 cm ^-1 corresponds to the C-H out-of-plane deformation vibration of 1,4-substituted benzene, the absorption peak at a wavenumber of 888 cm ^-1 is 1,
Corresponding to C-H out-of-plane bending vibration of 3,5-substituted benzene,
The absorption peak at a wave number of 1008 cm ^-1 corresponds to the C-H in-plane bending vibration of 1,4-substituted benzene, and the wave number of 1490 cm ^-1.
The absorption peak at ^-1 corresponds to the C = C stretching vibration of the benzene ring. Also, the wave number 1674c that was characteristic of the raw material
No peak corresponding to the stretching vibration of carbonyl at m ^-1 is seen.

1 and 2 support that the acicular crystals produced are 1,3,5-tris (p-bromophenyl) benzene. The structural formula of 1,3,5-tris (p-bromophenyl) benzene is shown below.

[0020]

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Next, a method of polymerizing 1,3,5-tris (p-bromophenyl) benzene produced by the above method to produce a polymer will be described. The following reactions were carried out in an argon gas atmosphere in order to prevent the reagents from reacting with oxygen or water.

After removing the resinous component soluble in hot methanol from the 1,3,5-tris (p-bromophenyl) benzene obtained by the above-mentioned method, 80 m per 4.8 g was removed.
l Toluene was added, and the insoluble matter was filtered off at 90 ° C. and recrystallized for purification. 0.215 g (0.4 mmol) of 1,
3,5-tris (p-bromophenyl) benzene was added to 2.
It was dissolved in 5 ml of tetrahydrofuran (THF). T
HF is distilled by adding calcium hydride.

The solution was cooled to -78 ° C., and 0.25 ml (0.4 mmol) of a 1.6 mol / l n-butyllithium hexane solution was added dropwise with stirring while stirring. A white precipitate was formed at the beginning of the dropping, but it was dissolved with continued stirring to become a yellow transparent solution.

To this reaction solution, 0.137 g (0.5 mmol) of magnesium bromide etherate dissolved in 0.5 ml of ether was added dropwise. The ether was obtained by predrying with calcium chloride overnight, adding calcium hydride, and distilling. When magnesium bromide etherate was added dropwise, a white precipitate was generated, but it dissolved as the reaction solution was returned to room temperature and became a yellowish brown transparent solution. By dropping magnesium bromide etherate, the halogen group of 1,3,5-tris (p-bromophenyl) benzene is converted to magnesium halide.

This solution was dropped into a solution of 18.3 mg (0.07 mmol) of nickel acetylacetonate dissolved in 10 ml of THF and refluxed, and polymerization was carried out by Grignard reaction. The reaction liquid became transparent blue shortly after starting the reflux. After 19 hours, the reaction was stopped by adding 0.05 ml of water.

The solvent was distilled off and the remaining viscous product was removed by 50
Unreacted components were removed by washing with 70 ml of acetone at 70 ° C. Further, 20 ml of acetone at 50 ° C. and 10 ml of 1N hydrochloric acid are added.
The product was washed twice with 10 ml of water, twice with 10 ml of water, and three times with 10 ml of methanol, and dried at 80 ° C. for 30 minutes to obtain the desired product as a white powder. The yield was 33.1 mg (yield 21.9.
%), And the melting point was 315 to 355 ° C.

FIG. 3 shows the infrared absorption spectrum of this desired product. The absorption peak at 812 cm ⁻¹ corresponds to the C—H out-of-plane bending vibration of 1,4-substituted benzene, and is 885 cm.
^-1 absorption peak is C-H of 1,3,5-substituted benzene
Corresponding to out-of-plane bending vibration, 1005 cm ^-1 and 1073
The absorption peak at cm ^-1 corresponds to the C-H in-plane bending vibration of benzene.

[0028] 1436cm ^-1, 1490cm ^-1, and 1
The absorption peak at 594 cm ^-1 corresponds to the C = C stretching vibration of benzene. FIG. 3 shows that the product is (C ₂₄ H ₁₅ ) _n B
It supports r _{n + 2} . When the elemental analysis of the product was performed, C: 70.54, H: 3.71, Br:
It was 26.63. From this, it is considered that the average of n in the above general formula is 6. The average degree of polymerization of the product is 6, but the actual polymer is a mixture of products with different degrees of polymerization. The resulting polymer is believed to be primarily a mixture of products with a degree of polymerization of 5-10.

The product (C ₂₄ H ₁₅ ) ₆ Br ₈ is TH
It was soluble in F. 10 for 1 ml of THF
When a polymer in which mg of the product was dissolved was applied onto a glass substrate kept at 30 to 40 ° C. and naturally dried, a colorless and transparent film having a thickness of 10 μm could be obtained.

The polymer film and antimony pentafluoride were placed in an evacuated container for doping. The conductivity of the polymer film increased with the lapse of doping time, and the conductivity after 91 hours was 1.03 × 10 ⁻⁴ S / c.
It became m. Thus, a conductive polymer film could be prepared by preparing a polymer film using a soluble polymer and doping the polymer film with an electron accepting reagent.

Next, referring to FIGS. 4 to 8, the second embodiment of the present invention will be described.
An example will be described. First, 1, which is the raw material of the polymer
A method for producing 3,5-tris (5'-bromo-2'-thienyl) benzene will be described.

14.84 g (72.4 mmol) of 2-
70 ml of toluene was added to acetyl-5-bromothiophene and heated to 40 ° C. to dissolve. Then 0.1 ml
Of trifluoromethanesulfonic acid was added, and the mixture was reacted under reflux for 24 hours. Water generated by the reaction was removed using a trap. After the solvent was distilled off from the obtained brown reaction solution, dichloromethane was added to extract the soluble component. Further, the components were separated by column chromatography on a silica gel carrier using cyclohexane as a developing solvent, and recrystallized with hexane to obtain 1,3,5-tris (5′-bromo-2′-thienyl) benzene.

The yield was 1.12 g (yield 8.3%). The obtained 1,3,5-tris (5′-bromo-2 ′)
-Thienyl) benzene was a white needle crystal and its melting point was 186-189 ° C.

FIG. 4 shows an ultraviolet-visible absorption spectrum of the obtained white needle crystal. The horizontal axis represents the wavelength in nm,
The vertical axis represents the molar extinction coefficient in the unit of mM ⁻¹ cm ⁻¹ . Wavelength 3
Absorption due to π-π ^* transition is observed at the position of 05 nm. The molar extinction coefficient at this time was 62 mM ⁻¹ cm ⁻¹ .

FIG. 5 shows the infrared absorption of the obtained white needle crystals.
The spectrum is shown. Horizontal axis is wave number in cm^-1Is expressed as
The axis represents the transmittance in%. Wave number 786 cm^-1, 855
cm ^-1, 1449 cm^-1, And 1591 cm^-1Place
Has a characteristic absorption peak. Wave number 786 cm^-1
The absorption peak of is the C-H plane of 2,5-disubstituted thiophene.
Corresponding to external bending vibration, wave number 855 cm^-1Absorption peak of
Is the C-H out-of-plane bending vibration of 1,3,5-trisubstituted benzene.
Corresponding to movement, wave number 1449 cm^-1And 1591 cm^-1of
The absorption peaks of the benzene ring and thiophene ring are
It corresponds to C = C stretching vibration. From Figure 5
You can check the generation.

FIG. 6 shows an NMR (nuclear magnetic resonance) spectrum of a white needle crystal. The horizontal axis represents the deviation of the resonance frequency from the reference frequency in ppm. The analysis result of FIG. 6 is
It is as follows. That is, δ 7.07 (d, J (3-4) 3.8 Hz, 3H, H ^{3 '}
orH ^{4 ′} ) δ 7.12 (d, 3H, H ^{4 ′} orH ^{3 ′} ) δ 7.51 (s, 3H, H ² andH ⁴ andH ⁶ ). Here, δ is a chemical shift, the next number is the frequency (ppm) of the resonance frequency shift, d is the doublet, s is the singlet, J is the coupling constant, the next number is the frequency difference between the doublets, and H is the hydrogen atom. , H indicates the binding position. The peak at 7.25 ppm is considered to be due to non-deuterated CHCl ₃ mixed in CDCl ₃ used as the solvent.

FIG. 7 shows the hydrogen corresponding to the NMR spectrum.
It is a structural formula showing the position of an atom. H ⁿIs n of the benzene ring
Hydrogen atom bonded to the position^{n '}Is the n-position of thiophene
Represents a hydrogen atom bonded to the position.

The elemental analysis results of the white needle crystals are C: 38.58, H: 1.67, S: 10.04,
It was Br: 41.94. This is 1,3,5-tris (5′-bromo-2′-thienyl) benzene (C ₁₈ H
It almost agrees with the calculated value of ₉ S ₃ Br ₃ ). 1,3,3
The structural formula of 5-tris (5′-bromo-2′-thienyl) benzene is shown below.

[0039]

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Next, a method of polymerizing 1,3,5-tris (5'-bromo-2'-thienyl) benzene produced by the above method to produce a polymer will be described. The following reactions were carried out in an argon gas atmosphere in order to prevent the reagents from reacting with oxygen or water.

0.223 g (0.4 mmol) of 1,
3,5-Tris (5'-bromo-2'-thienyl) benzene was dissolved in 2.5 ml THF. THF is distilled by adding calcium hydride.

The solution was cooled to −78 ° C., and 0.25 ml (0.4 mmol) of a 1.6 mol / l n-butyllithium hexane solution was dropped with a syringe while stirring. After stirring for 10 minutes, 0.138 g (0.5 mmol) of magnesium bromide etherate dissolved in 0.5 ml of ether was added dropwise, and the temperature was returned to room temperature with stirring. The ether was obtained by predrying with calcium chloride overnight, adding calcium hydride, and distilling.
When magnesium bromide etherate was added dropwise, a white precipitate was produced, but it dissolved as the reaction solution was returned to room temperature and became a brown transparent solution.

This solution was added dropwise to a solution of 16.4 mg (0.06 mmol) of nickel acetylacetonate dissolved in 10 ml of THF and refluxed for polymerization.
After 23 hours, the reaction solution was returned to room temperature, and 0.05 ml of water was added to stop the reaction.

The solvent was distilled off using a rotary evaporator, and the remaining viscous product was washed with 80 ml of acetone at 50 ° C. to remove unreacted monomers. Furthermore, 20 ml of acetone at 50 ° C. and 10 ml of 1N hydrochloric acid were used twice, and 10 m of water was added.
It was washed twice with 1 times and twice with 10 ml of methanol, and dried under vacuum at 50 ° C. for 1 hour to obtain the desired product as a brown powder. Yield 69.9 mg (yield 43.8%), melting point 230-
It was 300 ° C. and contained an infusible component.

FIG. 8 shows the infrared absorption spectrum of this desired product. The absorption peak at 790 cm ⁻¹ corresponds to the C—H out-of-plane bending vibration of the 2,5-substituted thiophene, 854c
The absorption peak at m ^-1 is C of 1,3,5-substituted benzene.
-H corresponds to out-of-plane bending vibration.

The absorption peaks at 1447 cm ^-1 and 1588 cm ^-1 are C = C of the thiophene ring or benzene ring.
Supports stretching vibration. FIG. 8 shows that the product is (C ₁₈ H ₉
S ₃ ) _n Br _{n + 2} . When the elemental analysis of the product was performed, C: 50.48, H: 2.3
5, S: 22.40, Br: 25.17. From this, it is considered that n in the above general formula is 6. The average degree of polymerization of the product is 6, but the actual polymer is a mixture of products with different degrees of polymerization. The resulting polymer is believed to be primarily a mixture of products with a degree of polymerization of 5-10.

The product (C ₁₈ H ₉ S ₃ ) ₆ Br ₈ is
It was soluble in THF. In the second embodiment, the polymerization temperature is set to the boiling point of THF, that is, 65 to 67.
Although the temperature was set to 0 ° C, when the polymerization was carried out at a polymerization temperature of 45 to 55 ° C, 46.1 mg (yield 14.3%) of brown powder could be obtained. The melting point of this brown powder is 162-
It was 320 ° C.

FIG. 9 shows an infrared absorption spectrum of the brown powder obtained at a polymerization temperature of 45 to 55 ° C. 791c
The absorption peak of m ⁻¹ is C—H of 2,5-substituted thiophene.
Corresponding to out-of-plane bending vibration, the absorption peak at 858 cm ^-1 is
It corresponds to the C-H out-of-plane bending vibration of 1,3,5-substituted benzene.

The absorption peaks at 1448 cm ^-1 and 1588 cm ^-1 are C = C of the thiophene ring or benzene ring.
Supports stretching vibration. The brown powder polymer produced by this method has a polymerization temperature of 65% in the above second embodiment.
It had a higher solubility in THF than the polymer produced at ~ 67 ° C. A polymer solution in which 10 mg of the polymer was dissolved in 1 ml of THF was applied onto a glass substrate kept at 30 to 40 ° C. and naturally dried to obtain a thickness of 8
A brown transparent film of μm could be obtained.

The polymer film and antimony pentafluoride were placed in an evacuated container for doping. The conductivity of the polymer film increases with the lapse of doping time, and the conductivity after 500 hours is 1.28 × 10 ⁻⁴ S / c.
It became m. Thus, a conductive polymer film could be prepared by preparing a polymer film using a soluble polymer and doping the polymer film with an electron accepting reagent.

In the above embodiment, the conductive polymer film was formed.
Antimony pentafluoride was used as an electron-accepting reagent for
However, other reagents may be used. For example, PF_Five, A
sF _Five, BF_Three, BCl_Three, BBr_Three, SO_ThreeLouis of etc
Sulfuric acid may be used. Also, using an electron-donating reagent
Good.

In the above examples, the case where the electron-accepting reagent is added to give conductivity after the polymer film is prepared has been described. However, the reagent is added to the polymer solution and the solution is added to the glass substrate. May be coated on to prepare a conductive film.

Further, in the above embodiment, the case where bromine is bonded to the tips of the three arms of the monomer as the polymer raw material has been described, but the monomer is not limited to bromine, and other halogen elements are bonded. May be used.

The present invention has been described in connection with the preferred embodiments.
The present invention is not limited to these. For example, it will be apparent to those skilled in the art that various modifications, improvements, combinations, and the like can be made.

[0055]

As described above, according to the present invention,
A highly π-conjugated polymer that is soluble in a solvent can be obtained without introducing a substituent. A polymer film can be produced by a simple method by coating this polymer solution on a substrate and drying. Further, by conducting doping on the film, a polymer film having conductivity can be produced.

[Brief description of drawings]

FIG. 1 is a graph showing an ultraviolet-visible absorption spectrum of 1,3,5-tris (p-bromophenyl) benzene obtained in Example 1.

FIG. 2 is a graph showing an infrared absorption spectrum of 1,3,5-tris (p-bromophenyl) benzene obtained in Example 1.

FIG. 3 is a graph showing an ultraviolet-visible absorption spectrum of the 1,3,5-tris (p-bromophenyl) benzene polymer obtained in the first example.

FIG. 4 is a graph showing an ultraviolet-visible absorption spectrum of 1,3,5-tris (5′-bromo-2′-thienyl) benzene obtained in the second example.

FIG. 5 is a graph showing an infrared absorption spectrum of 1,3,5-tris (5′-bromo-2′-thienyl) benzene obtained in the second example.

FIG. 6 is a graph showing an NMR spectrum of 1,3,5-tris (5′-bromo-2′-thienyl) benzene obtained in the second example.

FIG. 7 shows 1,3,5-tris (5′-bromo-) for explaining positions of hydrogen atoms corresponding to NMR spectra.
FIG. 3 is a structural diagram of 2′-thienyl) benzene.

FIG. 8 is a graph showing an infrared absorption spectrum of a 1,3,5-tris (5′-bromo-2′-thienyl) benzene polymer obtained in the second example.

FIG. 9 is a diagram showing a modified example of the second embodiment with 1,3,5-
3 is a graph showing an infrared absorption spectrum of tris (5′-bromo-2′-thienyl) benzene.

Front page continuation (72) Inventor Masami Awai 20-21 Higashimanabe-cho, Tsuchiura-shi, Ibaraki

Claims (7)

[Claims] 1. A compound of the general formula A polymer comprising a repeating unit represented by: 2. The polymer according to claim 1, wherein the number of repeating units is 5 to 10. 3. A compound of the general formula A conductive polymer obtained by doping a polymer having a repeating unit represented by the formula with an electron-accepting reagent to impart conductivity. 4. The conductive polymer according to claim 3, wherein the number of repeating units is 5 to 10. 5. The conductive polymer according to claim 3, wherein the electron accepting reagent is a Lewis acid. 6. A general formula: A method for producing a polymer, which comprises a step of producing a Grignard reagent from a compound represented by: and a step of polymerizing the Grignard reagent by a Grignard reaction. 7. The Grignard reagent has the general formula: The method for producing the polymer according to claim 6, which is represented by: