JP2005089318A - Phenyleneethynylenes and nanoparticle composition containing the same - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a composition which has solubility in a general-purpose solvent, can easily form a film by coating its solution, and effectively exhibits the properties of a metal and semiconductor nanoparticles to be incorporated as the bulk properties of the film. <P>SOLUTION: Phenyleneethynylenes are represented by formula (1) (wherein R<SP>1</SP>and R<SP>2</SP>may be different from each other and each is a 10-500C hydrocarbon residue; X is a thiol group, a phosphate group, a carboxy group, a sulfo group, an amino group or a hydroxy group; and n is an integer of 1-4). <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

  The present invention relates to phenyleneethynylene having a specific hydrocarbon side chain. The phenylene ethynylene of the present invention has a terminal functional group at the molecular end. A self-assembled composition (nanocomposite) containing metal or semiconductor nanoparticles at a high concentration can be easily obtained by utilizing the ability of the terminal functional group to bind to a transition metal element or oxide thereof. Such a nanocomposite contains a dopant substance capable of interacting with a pi-electron conjugated system as necessary, exhibits high conductivity, and has solvent solubility and coating film-forming ability. Therefore, it is used for paints, inks, conductive films and the like having both conductivity and coating properties.

  The phenylene ethynylene skeleton is a pi-electron conjugated system in which an acetylene structure and a benzene ring are bonded. Since the acetylene bond is rigid, even if there is free rotation of a single bond with the benzene ring, the pie electron cloud overlaps due to the free rotation like a phenylene vinylene skeleton (bond of carbon-carbon double bond and benzene ring). It is hard to produce change of. Therefore, it can be said that the chemical structure has the possibility of most stably expressing the conductivity of the pi-electron conjugated system regardless of the external environment and the substituent effect.

  As a conductive polymer having coordination ability to nanoparticles containing a transition metal element, solvent solubility and melt flowability, Patent Document 1 discloses that a mercapto group (thiol group) is present at both ends and dendron is on the side. Polyphenylene ethynylene having a chain (degree of polymerization of 5 to 500) is disclosed. The patent document discloses a composition comprising such polyphenylene ethynylene and metal or semiconductor nanoparticles (number average particle diameter is 1 to 50 nm).

  This composition exhibits conductivity by using conductive metal nanoparticles such as gold and silver, and if necessary, containing a dopant substance such as iodine. However, since the molecular weight of polyphenylene ethynylene is large, the concentration of the terminal thiol group of the conductive polymer that forms a bond with the metal nanoparticles, which is a necessary condition for high conductivity, is small. Therefore, even if a large amount of metal nanoparticles are contained in the composition, the number of metal nanoparticles that bind to the terminal thiol group and effectively work for conductivity is extremely limited. There were restrictions.

Even when, for example, a II-VI compound semiconductor (such as zinc oxide) that generates a bond with a thiol group is used as a nanoparticle, the semiconductor property is expressed as a bulk physical property of the composition. There was a limitation for the same reason as sex.
JP 2002-322348 A

  Provided is a composition that has solubility in a general-purpose solvent, can be easily formed into a thin film by application of the solution, and effectively expresses the properties of the contained metal or semiconductor nanoparticles as the bulk physical properties of the thin film. That is true.

(1) The molecular weight of the high molecular weight phenylene ethynylenes having terminal functional groups, which is a conventional technique, is improved to the minimum and the concentration of the terminal functional groups is significantly improved, thereby effectively utilizing metal and semiconductor nanoparticles at high concentrations. It has become possible.
(2) Necessary while satisfying the effective use of metal and semiconductor nanoparticles described in the general formula (1) at a high concentration by keeping the carbon number of the side chain of the phenyleneethynylene structure within a certain range. Secure solvent solubility.
(3) The specific thing represented by the thiol group was discovered as an effective thing of the terminal functional group as described in General formula (1) postscript.
(4) In particular, in the preparation of phenylene ethynylenes having the most effective thiol group as the terminal functional group, the deacetylation process of the compound in which the thiol group as a precursor is protected with an acetyl group is studied and supported. It has been found that a method via a disulfide phenylene ethynylene oligomer is very preferable.

The present invention has been achieved by the means described above.
That is, the first gist of the present invention resides in phenyleneethynylenes represented by the following general formula (1).

However, in the general formula (1), R ¹ and R ² represent a hydrocarbon residue having 10 to 500 carbon atoms which may be different from each other, and X is a function having a binding ability to a transition metal element or an oxide thereof. The group is any one of a thiol group, a phosphoric acid group, a carboxyl group, a sulfonic acid group, an amino group, and a hydroxyl group, and n represents an integer of 1 to 4.
The second gist of the present invention resides in a disulfide phenylene ethynylene oligomer represented by the following general formula (2).

However, the general formula (2) R ¹ and R ² is a hydrocarbon residue is a good 10 to 500 carbon atoms which may be different from each other, n represents an integer of 1 to 4, p is from 2 to 20 Represents an integer.
The third gist of the present invention resides in a method for producing the phenylene ethynylenes, characterized in that the disulfide phenylene ethynylene oligomer is reduced.
The fourth gist of the present invention resides in a composition comprising the phenylene ethynylenes and metal or semiconductor nanoparticles.

  The fifth gist of the present invention resides in a thin film-like molded body comprising the above composition.

The nanocomposite of the present invention has the following characteristics.
(1) Dissolve in a solvent.
(2) A solution coating can be formed.
(3) Thin film molding by compression molding is possible.
(4) It has conductivity.

[Phenyleneethynylenes]
The phenylene ethynylenes in the present invention are represented by the general formula (1). However, in the general formula (1), R ¹ and R ² represent a hydrocarbon residue having 10 to 500 carbon atoms which may be different from each other, and X is a function having a binding ability to a transition metal element or an oxide thereof. The group is any one of a thiol group, a phosphoric acid group, a carboxyl group, a sulfonic acid group, an amino group, and a hydroxyl group, and n represents an integer of 1 to 4.

The lower limit of the number of carbon atoms of R ¹ and R ^{2 in} the general formula (1) is preferably 20 and more preferably 30 in terms of solvent solubility, while the upper limit of the carbon number of the phenyleneethynylenes is small. In terms of suppression, it is preferably 450, and more preferably 400.
R ¹ and R ^{2 in} the general formula (1) are preferably dendrimers from the viewpoint of solvent solubility. The dendrimer here is a hydrocarbon residue having a regular hyperbranched structure with a certain branched repeating unit. Specifically, polybenzyl ether dendrimers (J. Am. Chem. Soc., 112, 7638 (1990)) developed by Frechet et al. And having a repeating unit of 3,5-dihydroxybenzyl alcohol residue and aliphatic Polyether dendrimers (J. Am. Chem.
Soc., 120, 12996 (1998)), polyamidoamine dendrimers developed by Tomalia et al. (Described under the trade name “Star Burst” in the reagent catalog of Aldrich), polyether amide dendrimers developed by Newkome et al. Macromolecules, 24, 1443 (1991)), aromatic polyetherketone dendrimers developed by Morikawa (Macromolecules, 32, 1062 (1999)), polypropylene imine dendrimers (manufactured by DSM and listed in the Aldrich reagent catalog. Examples are those described under the trade name “DAB”). Of these, aliphatic polyether dendrimers and aromatic dendrimers such as polybenzyl ether dendrimers and aromatic polyether ketone dendrimers are preferred in terms of solvent solubility. Among them, polybenzyl ether dendrimers are easy to synthesize. Most preferred.

Although the dendrimer has a perfectly regular branched structure, a hyperbranched polymer having a hyperbranched structure that is less strict than this is also effective as the structure of R ¹ and R ^{2 in} the general formula (1). Examples of such structures include the aliphatic hyperbranched polymers described in Macromolecules, 32, 6380 (1999) and Macromolecules, 32, 6881 (1999).

The effect of the hyperbranched structure typified by a dendrimer is that the densely branched hyperbranches effectively coat the phenylene ethynylene main chain to impart solvent solubility. This is an advantage over a linear molecule having an equivalent molecular weight and a similar repeating unit, but there is no limitation on the branched structure of R ¹ and R ^{2 in} the general formula (1).
In the general formula (1), X is a functional group having an ability to bind to a transition metal element or an oxide thereof present on the surface of a metal or semiconductor nanoparticle that is an essential component of the composition described later. Is any of a thiol group, a phosphate group, a carboxyl group, a sulfonic acid group, an amino group, and a hydroxyl group. A plurality of X may be the same or different, but the same is preferable. The bond formed by these functional groups with the transition metal element or oxide thereof is usually a covalent bond, an ionic bond or a coordinate bond, but there is no limitation on the form thereof, and the phenylene ethynylene main chain is formed through the functional group. It is only necessary to play a role of bonding to the surface of the metal or semiconductor nanoparticle. Preferred functional groups are a thiol group, a phosphate group, a carboxyl group, and an amino group in terms of bonding strength. The thiol group is most preferable because it exhibits a strong binding force to a wide range of transition metal elements. Phosphoric acid groups form strong bonds to transition metal oxides (eg, zinc oxide, titanium oxide, zirconium oxide, etc.) through acid-base reactions and are therefore very effective for nanoparticles with transition metal oxide surfaces. .

In the general formula (1), n represents an integer of 1 to 4, and is preferably 1 or 2 and most preferably 1 from the viewpoint of suppressing the molecular weight of the phenyleneethynylenes to be small and ease of synthesis.
[Disulfide phenylene ethynylene oligomer]
In producing the phenylene ethynylenes, a disulfide phenylene ethynylene oligomer represented by the following general formula (2) is useful as a precursor.

However, in the general formula (2), R ¹ , R ² and n are the same as those in the general formula (1), and p represents an integer of 2 to 20. The upper limit of p is preferably 15 and more preferably 10 from the viewpoint of the reaction yield in which the disulfide phenylene ethynylene oligomer produces the phenylene ethynylene by the reduction reaction described later, and the lower limit of p is disulfide phenylene. In view of chemical stability and ease of synthesis of the ethynylene oligomer, it is preferably 3, and more preferably 4.

  Such a disulfide phenylene ethynylene oligomer is prepared from phenylene ethynylene having a terminal thiol group protected by a protecting group A represented by the following general formula (3). The protecting group A is not limited as long as it does not cause chemical changes in other parts of the molecular structure of the general formula (3) under the deprotection conditions. For example, an acyl group such as an acetyl group or a benzoyl group is preferable. Used. As the acyl group, an acetyl group is most suitable because deprotection is easy.

When the protecting group A in the general formula (3) is an acetyl group, as a suitable method for deacetylation, an excess equivalent (usually 5 to 100 equivalents) of an inorganic strong base such as sodium hydroxide is added to an aqueous organic solvent (for example, tetrahydrofuran). / Aqueous system etc.) can be exemplified.
The disulfide phenylene ethynylene oligomer is converted into the phenylene ethynylene by a reduction reaction. In the reduction reaction, two hydrogen atoms are supplied to one disulfide bond (—S—S—) to generate two thiol groups. There is no limitation on the reducing agent used in such a reduction reaction. For example, borohydride salts such as lithium borohydride, sodium borohydride, potassium borohydride, lithium aluminum hydride, sodium aluminum hydride, potassium aluminum hydride And aluminum hydride salts such as Of these, borohydride salts such as sodium borohydride are preferred, and the reaction conditions are, for example, by dissolving disulfide phenylene ethynylene oligomer in a mixed solvent of ethanol and tetrahydrofuran and adding an excess equivalent amount of borohydride salt (usually 10 ~ 300 equivalents) at room temperature.

[Nanoparticle composition]
The composition comprising phenyleneethynylenes and metal or semiconductor nanoparticles is soluble in a general-purpose solvent, and a thin film can be formed by applying the solution to a substrate. The thin film exhibits conductivity or semiconductivity. It will be a thing. Such a nanoparticle-containing composition may contain a dopant substance capable of interacting with the pi-electron conjugated system, if necessary, for the purpose of improving electrical conductivity.

  The nanoparticle in the present invention is a particle having an average particle diameter of 3 to 100 nm. The upper limit is preferably 70 nm, more preferably 50 nm, and most preferably 30 nm in terms of increasing electrical characteristics (conductivity or semiconductivity) and increasing the light transmittance of the composition (that is, reducing light scattering). The lower limit is preferably 5 nm, and more preferably 7 nm, from the viewpoint of ensuring electrical properties with sufficient crystallinity as the metal or semiconductor of the nanoparticle itself.

  The dopant substance has a function of coordinating with an acetylene bond in the phenylene ethynylene structure to cause polarization of the pi electron cloud to generate a charge. This effect is well known as a means for improving conductivity in a conductive polymer. As a dopant substance, known substances such as halogen simple molecules such as iodine and bromine, camphorsulfonic acid and p-toluenesulfonic acid are known. And organic sulfonic acids and the like. Among these, iodine is particularly effective in terms of doping properties in a thin film-like molded body to be described later.

  The said metal nanoparticle is a nanoparticle which makes a transition metal element simple substance or its multiple types of alloy a composition. As such a metal composition, a transition metal such as gold, platinum, silver, palladium, rhodium, zinc, copper, nickel, iron, or an alloy of these transition metals (containing non-transition metal elements such as carbon, magnesium, aluminum, etc.) May be exemplified). Among these, noble metals such as gold, platinum, silver, and copper are preferable because they are less likely to cause electrical reactions and chemical reactions such as oxidation, and gold and platinum are optimal in terms of chemical stability.

As the composition of the semiconductor nanoparticles, SnO ₂ , Sn (II) Sn (IV) S ₃ , SnS ₂ ,
Compound of periodic table group 14 element and periodic table group 16 element such as SnS, SnSe, SnTe, PbS, PbSe, PbTe, etc., periodic table of GaN, GaP, GaAs, GaSb, InN, InP, InAs, InSb, etc. Compound of Group 13 element and Group 15 element of periodic table (or III-V compound semiconductor), Ga ₂ S ₃ , Ga ₂ Se ₃ , Ga ₂ Te ₃ , In ₂ O ₃ , In ₂ S ₃ ,
Compound of periodic table group 13 element and periodic table group 16 element such as In ₂ Se ₃ and In ₂ Te ₃ , ZnO, ZnS, ZnSe, ZnTe, CdO, CdS, CdSe, CdTe, HgS, HgSe, HgTe, etc. A periodic table group 12 element and a periodic table group 16 element compound (or II-VI group compound semiconductor), Cu ₂ O, Cu ₂ Se, etc. periodic table group 11 element and periodic table group 16 element Compound of periodic table group 11 element and periodic table group 17 element such as CuCl, CuBr, CuI, AgCl, AgBr, etc., Compound of periodic table group 10 element and periodic table group 16 element such as NiO , CoO, CoS periodic table group 9 element and periodic table group 16 element compound, α-Fe ₂ O ₃ , γ-Fe ₂ O ₃ , Fe ₃ O ₄ , FeS periodic table group 8 Compounds of elements and group 16 elements of the periodic table Periodic table compounds of group 7 element and Periodic Table Group 16 element such as MnO, the compounds of the periodic table group 6 element and Periodic Table Group 16 element such as _{MoS 2, WO 2, VO,} VO 2, Ta Compound of periodic table group 5 element and periodic table group 16 element such as ₂ O ₅ , TiO ₂ , Ti ₂ O ₅ , Ti ₂
Titanium oxides such as O ₃ and Ti ₅ O ₉ (the crystal type may be any of rutile type, rutile / anatase mixed crystal type, or anatase type), CdCr ₂ O ₄ , CdCr ₂ Se ₄ , CuCr ₂ S ₄ And chalcogen spinels such as HgCr ₂ Se ₄ , BaTiO _{3 and the} like. Among these semiconductor compositions, preferred are ZnO, ZnS, ZnSe, ZnTe, CdO, CdS, CdSe, CdTe and other II-VI group compound semiconductors, and the periodic table Group 4 elements such as the above-mentioned titanium oxides. A II-VI group compound semiconductor composition containing Zn and a group 16 element is most preferable. In such a semiconductor composition, for example, Al, Mn, Cu, Zn, Zr, Sn, Ag, Cl, Ce, Eu, Tb, Er, etc. are used as trace amounts of doping substances (meaning impurities intentionally added) as necessary. An element may be added, and by using such a doped substance, for example, ZnS: Mn, ZnS: Tb (where the element after “:” is a doped substance) and the like, a preferable light emitting ability in the visible region or the like can be obtained. In some cases, excellent light-resistant stability such as TiO ₂ : Zr may be imparted.

Examples of the semiconductor nanoparticles include A.I. R. Kortan et al. Am. Chem. Soc. 112, p. 1327 (1990) or US Pat. No. 5,985,173 (1999), for the purpose of improving the electronic excitation characteristics of the semiconductor crystal, it consists of an inner core (core) and an outer shell (shell). The so-called core-shell structure is suitable when the exciton absorption / emission band is used because the quantum effect stability of the semiconductor crystal forming the core may be improved. In this case, it is generally effective to form an energy barrier by using a shell semiconductor crystal having a forbidden band width (band gap) larger than that of the core. This is presumed to be due to a mechanism that suppresses the influence of an undesirable surface level due to the influence of the external world such as impurities and crystal lattice defects on the crystal surface. Although the composition of the semiconductor crystal suitably used for such a shell depends on the band gap of the core semiconductor crystal, the bulk band gap is 2.0 eV or more at a temperature of 300 K, for example, BN, BAs, GaN And III-V compound semiconductors such as GaP,
II-VI group compound semiconductors such as ZnO, ZnS, ZnSe, ZnTe, CdO, and CdS are preferably used. Among these, a semiconductor crystal composition that is a more preferable shell is a III-V group compound semiconductor such as BN, BAs, or GaN, or I such as ZnO, ZnS, ZnSe, or CdS.
The bulk state band gap of a group I-VI compound semiconductor, etc. is 2.3 eV or more at a temperature of 300 K, and the most preferred is the bulk state band gap of BN, BAs, GaN, ZnO, ZnS, ZnSe, etc. Is 2.5 eV or more at a temperature of 300K.

The optimum mixing ratio of the phenylene ethynylenes and the nanoparticles varies depending on the average particle size of the nanoparticles (that is, the surface area bonded to the phenylene ethynylenes), but is usually 9/1 to 1/9 by weight. The weight ratio is preferably 7/3 to 3/7.
Although there is no restriction | limiting in the method of mixing the said nanoparticle with phenylene ethynylene, Usually, a nanoparticle is previously coat | covered with the organic ligand in order to prevent aggregation. Such organic ligands must be displaceable by the thiol end groups of the phenylene ethynylenes of the present invention. Examples of such organic ligands include alkanethiols having 4 or more carbon atoms such as n-butanethiol, n-hexanethiol, n-octanethiol, and n-dodecanethiol, and total carbons such as trioctylphosphine oxide and tributylphosphine oxide. Examples thereof include trialkylphosphine oxides having a number of twelve or more, alkylamines having twelve or more carbon atoms having active hydrogen such as dodecylamine and hexadecylamine, and long-chain fatty acids such as oleic acid and stearyl acid.

In the composition comprising the phenyleneethynylenes of the present invention and metal or semiconductor nanoparticles, if necessary, various known additives used for resin materials, such as heat stabilizers, antioxidants, radical scavengers, etc. UV absorbers, plasticizers, mold release agents, reinforcing materials (glass fibers, glass beads, glass flakes, carbon fibers, mica, talc, kaolin, clay minerals, etc.) may be added.

[Thin-film shaped body]
The composition comprising the phenylene ethynylenes and metal or semiconductor nanoparticles is a method of coating and drying the solution on a substrate (hereinafter sometimes referred to as a casting method), a compression molding method, an extrusion molding or an injection molding. It is useful to form a thin film-like molded body by a known molding means such as a thermoplastic molding method.

  The film thickness of such a thin film-shaped molded body is usually 0.1 to 500 μm, and when the light transmittance of the thin film is necessary, such as when used for an electrode of a device that transmits light such as a display or a solar cell, the upper limit is preferably 100 μm, more preferably 80 μm. On the other hand, the lower limit is preferably 0.3 μm, more preferably 0.5 μm, in terms of electrical characteristics (conductivity or semiconductivity) and thin film strength.

Although there is no restriction | limiting in the board | substrate of this thin film-like molded object, As the material, glass (semiconductor etc.), metal (aluminum, SUS, etc.), carbon material (graphite etc.), resin (PET film, polycarbonate resin film, Examples thereof include polyethylene, polypropylene resin films, vinyl chloride resin films, and the like.
When the thin film-shaped molded product is produced by the casting method, the solvent used is not limited, but as the solvent, hydrocarbons such as toluene and hexane, ethers such as tetrahydrofuran (THF) and ethyl cellosolve, acetone and methyl ethyl ketone Ketones such as chloroform, halogenated hydrocarbons such as methylene chloride and chlorobenzene, amides such as N, N-dimethylformamide and N-methylpyrrolidone, methanol, ethanol, n-propanol, isopropyl alcohol, n-butanol and the like These alcohols, water and the like are exemplified, and these may be used in combination of a plurality of kinds as required. When a polybenzyl ether dendrimer having excellent solubility is used as the side chain of phenylene ethynylene, a suitable solvent is THF or chloroform, and THF is most excellent in terms of environmental safety.

The concentration of the composition containing the phenylene ethynylenes and metal or semiconductor nanoparticles in the solution of the casting method is usually 0.01 to 50% by weight, and the lower limit is preferably 0.1 in terms of productivity. The upper limit is preferably 40% by weight, more preferably 30% by weight in terms of solution viscosity (applicability).
When the thin film-like molded product of the present invention is molded by the compression molding method, the molding temperature is not limited, but is usually 0 to 200 ° C., preferably 10 to 150 ° C. in terms of moldability and thermal deterioration prevention, and more preferably. It is the range of 20-120 degreeC.

When the thin film-like molded product of the present invention is molded by the thermoplastic molding method, the molding temperature is not limited, but is usually 50 to 300 ° C., preferably 80 to 270 ° C., more preferably in terms of moldability and thermal deterioration prevention. Is in the range of 90-250 ° C.
EXAMPLES Specific embodiments of the present invention will be described in more detail with reference to the following examples, but the present invention is not limited to these examples unless it exceeds the gist.

[Measurement equipment and conditions]
(1) Nuclear magnetic resonance spectrum (NMR): JSX GSX500 type, LA500 type magnetic field strength: 11.75 Tesla, ¹ H (500 MHz), ¹³ C (125 MHz), mainly deuterated chloroform. Measured at room temperature.
(2) Mass spectrometry: [1] MALDI-TOF-MS measurement was performed by Applied Biosystems Voyager Elite-DE. [2
] DCI (EI) -MS measurement is JMS-700 / Mstation manufactured by JEOL.
(3) GPC: Shimadzu high performance liquid chromatograph (LC-VP series). Solvent (mobile phase) is chloroform (Kanto Chemical), column is Shodex GPC K-806, GPC Shim-Pack 802C, temperature is 4
A calibration curve was prepared using monodisperse polystyrene (Showa Denko: Shodex standar d) having a molecular weight of 0 ° C., a flow rate of 1.00 mL / min, a detector of UV (254 nm), and a known molecular weight.
(4) Scanning electron microscope Hitachi, Ltd. S-5200 Resolution 0.5nm (30KV), 1.8nm (1KV)
(5) Photo-excitation emission spectrum RF-5300PC spectrophotometer manufactured by Shimadzu Corporation, measured with quartz cell
(6) Absorption spectrum UV-3150 made by Shimadzu Corporation UV / visible spectroscopic analysis, measured by quartz cell
(7) Electrochemical measurement: Power supply Keithley SourceMeter 2400
(8) Electrochemical measurement: Tester Keithley Multimeter 2000
(9) Film thickness measuring device: Tokyo Seimitsu Co., Ltd. SURFCOM 1400D
[Conductivity measurement method]
Using a commercially available hydraulic press tablet forming machine (inner diameter 2.5 mm), a well-dried 2-3 mg sample was formed into a disk shape. Insulating film of tetrafluoroethylene-hexafluoropropylene copolymer (film thickness: 25 μm) with two gold glass-deposited glass substrates (15 mm × 30 mm) as electrodes, with a circular hole (diameter 3 mm) between them A sample molded into the disk shape was placed in the hole of the insulating film. The sample was sandwiched between clips and then heated and dried under reduced pressure (100 ° C., 3 hours or more). After measuring the film thickness, the sample was placed in a 300 mL three-necked flask, wired to the electrode, sealed, and repeatedly deaerated inside the flask and replaced with dry argon gas several times, and then measured at room temperature.

[Iodine doping treatment method]
The electrode substrate with the sample was placed in a 50 mL three-necked flask that had been repeatedly degassed and replaced with dry argon gas, and a portion of iodine was further sealed. The vacuum line was pulled once, the decompression was stopped, and the mixture was left for 30 minutes. Thereafter, the electrode was taken out and adjusted by reassembling the electrode, and the conductivity measurement was performed.

[Synthesis Examples, Examples and Comparative Examples]
Synthesis Example 1: Synthesis of S-acetyl-4-iodothiophenol A mixture of water (230 mL) and concentrated sulfuric acid (40 mL) was ice-cooled, and 4-iodobenzenesulfonyl chloride (10 g) and zinc powder (13.6 g) were added. The mixture was stirred for 30 minutes and then heated to reflux for 6 hours. After completion of the reaction, water (50 mL) and saturated aqueous ammonium chloride solution (170 mL) were added, the product was extracted with diethyl ether, and the obtained organic phase was washed with saturated aqueous sodium chloride solution and dried over sodium sulfate. The organic phase was concentrated under reduced pressure and purified by silica gel column chromatography to obtain a mixture of the desired 4-iodobenzenethiol and the corresponding disulfide. It was found that 4-iodobenzenethiol easily converted to a disulfide form when left in the atmosphere. In the present invention, after actively converting 4-iodobenzenethiol to a disulfide form, the reduction of the disulfide and the acetylation of the thiol produced by the reduction are performed simultaneously in Org. Lett. 26, 4295 (2001) was used. That is, the disulfide of 4-iodobenzene thiol N, the N- dimethylformamide (DMF) solution, a reducing agent which is separately adjusted at room temperature _{[(n-C4H9) 3 PH} ] BF 4 and diisopropylethylamine 1: One mixed solution and about 1 equivalent of water were added and stirred, and then acetic anhydride was added to obtain a terminal group component S-acetyl-4-iodothiophenol in which the thiol was protected with an acetyl group.

Synthesis Example 2: Synthesis of diethynylenebenzene bonded with polybenzyl ether dendrimer According to the method described in J. Am. Chem. Soc., 112, 7638 (1990), the phenyl group has a branched terminal structure. Third generation polybenzyl ether dendrimers were prepared. However, 3,5-bis [3,5-bis (benzyloxy) benzyloxy] benzyl bromide (abbreviated as [G-2] -Br) which is a second-generation bromide dendron supplied from Tokyo Kasei Co., Ltd. as a raw material. It was used. That is, [G-2] -Br (2.05 equivalent) and 3,5-dihydroxybenzyl alcohol (Aldrich; 1.0 equivalent) were freshly ground in a mortar with potassium carbonate (2.5 equivalent) and 18 -A 3rd generation dendron [G-3] -OH was obtained by conducting an etherification reaction in which acetone was used as a solvent in the presence of crown-6 ether (0.2 equivalents) and condensed by heating and stirring at 60 ° C. This was recrystallized and purified from a methanol / ethyl acetate mixed solvent, and brominated with carbon tetrabromide (1.25 equivalents) and triphenylphosphine (1.25 equivalents) in a dry THF solvent. 3rd generation bromide dendron [G-3] -Br was obtained. This [G-3] -Br was also recrystallized and purified from a methanol / ethyl acetate mixed solvent, and its structure and purity were confirmed by NMR and FT-IR spectra being consistent with those described in the above literature. Using the thus obtained [G-3] -Br, a diethynylenebenzene having a dendrimer bonded thereto was synthesized as follows. That is, cuprous chloride (0.05 equivalent) and dichlorobis (triphenylphosphine) palladium (II) (0. 0 equivalent) to 1,4-dihydroxy-2,5-diiodobenzene (1.0 equivalent) with stirring. 05 equivalents) were sequentially added at room temperature, and evacuation and nitrogen substitution in the container were repeated. Trimethylsilylacetylene (3.0 equivalents) and diisopropylamine (3.0 equivalents) were sequentially added thereto, reacted at 60 ° C. for 4 hours, diluted with toluene, and filtered to remove solids. This was purified by silica gel column chromatography to obtain 1,4-dihydroxy-2,5-bis (trimethylsilylethynyl) benzene. Next, this was stirred with methanol in excess of anhydrous potassium carbonate at room temperature for one day, and purified by silica gel column chromatography using methanol / methylene chloride as an effluent solvent to obtain 1,4-dihydroxy-2,5-diethynyl. Benzene was obtained. The chemical structure of these products was confirmed by 1H-NMR. Further, the third-generation bromide dendron [G-3] -Br (2.1 equivalent) synthesized above, 1,4-dihydroxy-2,5-diethynylbenzene (1.0 equivalent), anhydrous potassium carbonate (5 (0.0 equivalent) was repeatedly evacuated and purged with nitrogen, dried DMF was added thereto, and the mixture was stirred at 60 ° C. for 6.5 hours. The reaction solution was poured into a large excess of ice water with good stirring, and the resulting solid was filtered off and purified by silica gel column chromatography to bind the desired third-generation polybenzyl ether dendron side chain with diethynylenebenzene ( Hereinafter, [G-3] 2E2) was obtained. The structure of this product is that the signals attributed to the dendrimer-derived (benzylic position and benzene ring), ethynyl group, and benzene ring to which the ethynyl group binds were clearly observed, and their integration. The value ratio was confirmed.

Synthesis Example 3: Synthesis of phenylene ethynylene having an S-acetyl group terminal to which a third-generation polybenzyl ether dendron side chain is bonded (hereinafter, phenylene ethynylene having an S-acetyl group terminal is abbreviated as PhE-SAc).
Chem. Eur. J. et al. ; The following reaction was performed with reference to Volume 23, 5118 (2001). Diethynylenebenzene [G-3] 2E2 (350 mg, 1 equivalent), triphenylphosphine (0.41 equivalent), dibenzylideneacetone palladium (3 equivalents) to which the third generation polybenzyl ether dendron side chain obtained in Synthesis Example 2 was bonded. 0) (0.1 eq), copper iodide (0.2 eq), S-acetyl-4-iodothiophenol (3.25 eq) are added to the glass reactor and the reactor is evacuated and argon gas. After repeating the substitution several times, dry THF was added as a solvent, then diisopropylethylamine (8.2 equivalents) was added, and the mixture was stirred at 50 ° C. overnight. The reaction solution was concentrated with an evaporator, and the product was extracted with chloroform and washed with water. The chloroform solution was dried over magnesium sulfate, concentrated again, and silica gel column chromatography (eluent: dichloromethane / n-hexane / diethyl ether = 10/1 /
Separation and purification in 1), and further purification by reprecipitation method in which components dissolved in dichloromethane are added to ethanol, and the target PhE-SAc (hereinafter referred to as G3-PhE-SAc) bound to the third-generation polybenzyl ether dendron side chain. Abbreviated). The structure of the compound was confirmed by nuclear magnetic resonance spectrum, MALDI-TOF MS analysis, ultraviolet-visible absorption spectrum measurement, and fluorescence spectrum measurement.

¹ H NMR (CDCl ₃ ) d 2.25 (s, 6H,), 4.90-4.92 (m, 16H,), 4.98 (s, 32H), 5.01 (s, 4H
), 6.52-6.55 (m, 14H), 6.60-6.61 (m, 8H), 6.65 (m, 16H), 6.79 (s, 2H), 7.03 (s, 2H), 7.15 (d, 4H, J = 8.2 Hz), 7.27-7.41 (m, 40H), 7.50 (d, 4H, J = 8.6Hz). Mass spectrometry: Ions (m / z: 3634) added with sodium were detected.
Synthesis Example 4 Synthesis of PhE-SAc with First-Generation Polybenzyl Ether Dendron Side Chains In Synthesis Example 3, instead of diethynylenebenzene with the third-generation polybenzyl ether dendron side chains, first-generation polybenzyls The synthesis was carried out in the same procedure using dietinylene benzene (prepared in the same manner by applying the procedure of Synthesis Example 2) to which an ether dendron side chain was bonded. The reaction product of Synthesis Example 3 was excellent in solvent solubility, but in this Synthesis Example, a product that was hardly soluble in solvents such as tetrahydrofuran and chloroform was given. Purification was performed by thoroughly washing the hardly soluble product solid with water to remove inorganic components, collecting insoluble matter dispersed in chloroform with a filter paper, and drying. The structure of the compound was confirmed by nuclear magnetic resonance spectrum (solvent: deuterated dimethylformamide-d ₇ ) and MALDI-TOF MS analysis, and PhE-SAc (hereinafter referred to as “the first generation polybenzyl ether dendron side chain”) bound thereto. (Abbreviated as G1-PhE-SAc).

Synthesis Example 5 Synthesis of PhE-SAc with Second Generation Polybenzyl Ether Dendron Side Chains In Synthesis Example 3, the second generation polybenzyl was used instead of the diethylene benzene with the third generation polybenzyl ether dendron side chains attached. The synthesis was carried out in the same procedure using a diethylene benzene bonded with an ether dendron side chain. The reaction product of this synthesis example was slightly more crystalline than the reaction product of synthesis example 3, but the solvent solubility was equivalent. Purification was carried out in the same manner as in Synthesis Example 3. The structure of the compound was confirmed by nuclear magnetic resonance spectrum (NMR) and MALDI-TOF MS analysis, and the target PhE-SAc (hereinafter abbreviated as G2-PhE-SAc) bound to the second-generation polybenzyl ether dendron side chain was obtained. Obtained.

Synthesis Example 6: Synthesis of PhE-SAc having an n-hexyloxy side chain First, 1,4-diethynyl-2,5-bishexyloxybenzene as an intermediate was synthesized. 1,4-dihydroxy-2,5-diethynylbenzene (304 mg, 1 eq), 1-iodohexane (2.2 eq) and calcium carbonate (5 eq) are added to the glass reactor and the reactor is evacuated. After repeating the argon gas replacement several times, dry acetone was added as a solvent and the mixture was stirred at 60 ° C. overnight. The reaction solution is concentrated with an evaporator, and the product is extracted with chloroform. The organic phase is washed with water, dried over magnesium sulfate, concentrated again, and separated and purified by silica gel column chromatography (eluent: chloroform / n-hexane = 1/1). A white powder of 1,4-diethynyl-2,5-bishexyloxybenzene was obtained. 1,4-diethynyl-2,5-bishexyloxybenzene (132 mg, 1 equivalent), triphenylphosphine (0.41 equivalent), dibenzylideneacetone palladium (0) (0.1 equivalent), iodination thus obtained Copper (0.2 eq) and S-acetyl-4-iodothiophenol (3.25 eq) were added to the glass reactor, and after evacuation and argon gas substitution in the reactor were repeated several times, dry THF was added. As a solvent, diisopropylethylamine (8.2 equivalents) was further added with stirring. This was stirred at 50 ° C. all day and night. The reaction solution was concentrated with an evaporator, the product was extracted with chloroform, and the organic phase was washed with water. This organic phase is dried over magnesium sulfate, concentrated again, and separated and purified by silica gel column chromatography (eluent: chloroform). Further, the chloroform solution is poured into ethanol for reprecipitation, and the desired n-hexyloxy side chain is removed. The obtained PhE-SAc (hereinafter abbreviated as Hex-PhE-SAc) was obtained as a pale yellow solid. The molecular structure of this compound was confirmed by nuclear magnetic resonance spectrum and mass spectrometry together with the intermediate.

Synthesis Example 7: Synthesis of gold nanoparticles The following operations were performed based on the two-phase reduction method described in Brush et al .; J. Chem. Soc. Chem. Commun., Page 801 (1994). An aqueous solution of chloroauric acid (HAuCl ₄ ) (30 mmol / dm ^−)
3 ) 15 mL and 40 mL of a tetraoctylammonium bromide toluene solution (50 mmol / dm ⁻³ ) as a phase transfer catalyst were mixed and stirred, and when the red gold component moved to the toluene phase, hexanethiol (0.6 mL) And stirred for about 10 minutes until the organic layer became cloudy. To this, an aqueous solution of sodium borohydride (400 mmol / dm ^-3 ) was added at once and stirred. Care must be taken because it foams at this time. The organic layer immediately turned brown and stirring was continued for about 3 hours. After concentrating the toluene phase with an evaporator to a volume of several mL, ethanol was added and reprecipitated at −25 ° C. to remove unreacted alkanethiol and tetraoctylammonium bromide. The precipitate was collected with a filter paper, dissolved in a small amount of toluene again, ethanol was added, and the second reprecipitation was performed. This reprecipitation operation was further repeated three times. Finally, the precipitate was collected and dried to obtain a black powder of gold nanoparticles having hexanethiol as a ligand. By performing the same operation using dodecanethiol instead of hexanethiol, gold nanoparticles having dodecanethiol as a ligand could be prepared. The structure was confirmed with a scanning electron microscope (SEM), a transmission electron microscope (TEM), and a nuclear magnetic resonance spectrum (NMR: confirmation of the presence of hexanethiol).

Reference experiment 1: Spectrum in solution of G3-PhE-SAc The absorption spectrum of the THF solution of G3-PhE-SAc obtained in Synthesis Example 3 shows an absorption band derived from polybenzyl ether dendron around 280 nm. Absorption bands derived from the phenylene ethynylene structure were given respectively. When the absorption band of polybenzyl ether dendron was excited at 278 nm, an emission band derived from phenylene ethynylene was observed around 420 nm. Thus, only light emission derived from phenylene ethynylene was observed, so that it was confirmed that effective energy transfer from the polybenzyl ether dendron side chain to the phenylene ethynylene skeleton occurred.

Reference experiment 2: G3-PhE-SAc thin film spectrum The thin film was prepared by casting a THF solution on a quartz plate and evaporating the solvent. As a result of measuring the ultraviolet-visible absorption spectrum and the emission spectrum, the spectrum in the solution of Reference Experiment 1 was similar in many respects, but the emission band appeared near 450 nm and shifted to the longer wavelength side than the solution.

Preparation of disulfide phenylene ethynylene oligomer obtained by deacetylation of G3-PhE-SAc Chem. Eur. J. et al. 23, 5118 (2001) was applied. G3-PhE-SAc (250 mg) obtained in Synthesis Example 3 and sodium hydroxide (60 equivalents) were added to a tetrahydrofuran / water = 4/1 mixed solution and stirred overnight. The solvent was distilled off under reduced pressure, the reaction product was extracted with chloroform, the organic phase was washed with water and then with a saturated aqueous sodium chloride solution, and magnesium sulfate was added to the organic phase for drying. After distilling off the solvent under reduced pressure, a disulfide phenylene ethynylene oligomer (hereinafter abbreviated as “Oligo-G3-PhE-S”) formed by removing the acetyl group of G3-PhE-SAc was obtained. As for the molecular weight in terms of polystyrene, the weight average molecular weight Mw was 16000 and the ratio Mw / Mn to the number average molecular weight Mn was 1.6 by GPC.

Preparation of disulfide phenylene ethynylene oligomer obtained by deacetylating G2-PhE-SAc In Example 1, G2-PhE-SAc obtained in Synthesis Example 5 was used instead of G3-PhE-SAc, and the same experimental procedure was performed. Then, a disulfide phenylene ethynylene oligomer (hereinafter abbreviated as “Oligo-G2-PhE-S”) produced by removing the acetyl group was obtained. As for the molecular weight in terms of polystyrene, the weight average molecular weight Mw was 7200, and the ratio Mw / Mn to the number average molecular weight Mn was 1.6 by GPC.

Reference experiment 3: Attempt to deacetylate G3-PhE-SAc with secondary amine Based on the description of Organometallics, Vol. 14, page 4808 (1995), a solution of G3-PhE-SAc (35 mg) in chloroform solution (3 mL) Diethylamine or diisopropylamine (3 mL) was added and stirred at 50 degrees for 30 minutes to 3 hours. In this document, deacetylation of the terminal SAc group of conjugated phenyleneethylene proceeds, but hardly progressed in the system of this comparative example.
(Comparative Example 1)
Attempt to deacetylate Hex-PhE-SAc The same method as in Example 1 was performed in the same manner as in Example 1, but Hex-PhE-S having an n-hexyl group obtained in Synthesis Example 6.
Tried against Ac. Hex-PhE-SAc (26 mg) and sodium hydroxide (60 equivalents) were added to a tetrahydrofuran / water = 5/1 mixed solution and stirred. The reaction solution was poured into diethyl ether to precipitate a solid, which was washed with diethyl ether. The diethyl ether solution in which the solid was suspended was acidified by adding 3N hydrochloric acid. The organic phase was separated, washed with water and saturated aqueous sodium chloride solution and dried over magnesium sulfate. At this time, yellow hardly soluble insoluble matter gradually started to form. After distilling off the solvent, the components soluble in chloroform were confirmed by NMR. As a result, a complicated signal presumed to be an oligomer was given, and gradually insoluble components in chloroform were generated in the NMR measuring tube. As a result, subsequent nanocomposite preparation became difficult.

  From Comparative Example 1, it was found that the present invention, in which a dendrimer side chain is introduced into a conjugated rod-like molecule, exerts an effect of imparting solubility to a disulfide oligomer produced by deacetylation of a thiol group.

The following operation was performed with reference to dithiolphenylene ethynylene Tetrahedron, page 639 (2003) having a third generation dendron as a side chain. The disulfide phenylene ethynylene oligomer Oligo-G3-PhE-S (69 mg) having the third-generation dendron as a side chain obtained in Example 1 was dissolved in tetrahydrofuran (6 mL) containing 20% ethanol, and sodium borohydride was dissolved. (200 equivalents) was added and stirred overnight. The reaction solution was poured into 3N hydrochloric acid, and the organic solvent was distilled off under reduced pressure with an evaporator and extracted with chloroform. This organic phase is washed with water, dried over magnesium sulfate, and concentrated to dithiolphenylene ethynylene having the target third-generation dendron as a side chain (formula (4) below, where R is a third-generation polyphenyl having a phenyl terminal). Represents benzyl ether dendrimer residue.) As a yellow solid. This compound is hereinafter abbreviated as “G3-PhE-SH”.

¹ H NMR (CDCl ₃ ) 3.56 (s, 2H), 4.88-4.95 (m, 16H), 4.98 (s, 32H), 5.01 (s, 4H), 6.52-6.55 (m, 14H,), 6.53-6.61 (m, 8H), 6.65−6.66 (m, 16H), 6.77 (s, 2H), 7.03 (s, 2H), 7.27-7.40 (m, 40H, PhH), 7.60 (d, 4H, J = 8. 6 Hz), 7.68 (d, 4H, J = 8.6 Hz). Mass spectrometry: M + 3Na-2H (m / z: 3592) was detected.

Preparation of nanocomposite composed of G3-PhE-SH and gold nanoparticles Dithiolphenyleneethynylene G3-PhE-SH (20 mg) having the third-generation dendron obtained in Example 3 as a side chain is mixed with 20% ethanol / tetrahydrofuran. Into this, sodium borohydride (42 mg) was added and stirred for 30 minutes. To this, gold nanoparticles (13 mg) having hexanethiol obtained in Synthesis Example 7 as a ligand were added and stirred overnight. After completion of the reaction, it was thought that the ligand exchange reaction in which hexanethiol was substituted proceeded because there was a hexanethiol odor that was not present before the reaction. After evaporating the solvent under reduced pressure, extraction with chloroform yielded an organic phase, which was washed with water (twice), concentrated to a volume of several mL, ethanol was added, and the product was precipitated at -20 ° C. The solvent supernatant was removed by decantation, the precipitate was dissolved again in chloroform, ethanol was added and reprecipitation was carried out at -20 ° C. This reprecipitation operation was performed three times. The precipitate was collected and dried to obtain a target nanocomposite composed of G3-PhE-SH and gold nanoparticles. The structure is confirmed by scanning electron microscope and nuclear magnetic resonance spectrum (NMR:
Confirmation of bond formation with gold nanoparticles by thiol group).
(Comparative Example 2)
Trial of nanocomposite preparation by in-situ deacetylation reaction with aqueous ammonia Am. Chem. Soc. 117, 9529 (1995) and Chem. E
ur. J. et al. 23, 5118 (2001) avoids the formation of disulfide oligomers by the in-situ deacetylation reaction using NH ₄ OH in the production of a self-assembled film (SAM) using dithiol-terminated conjugated molecules. Therefore, the application of this method to this system was examined. G3-PhE-SAc (7 mg) obtained in Synthesis Example 3 was dissolved in tetrahydrofuran (0.5 mL) under an argon gas atmosphere, and gold nanoparticles having hexanethiol obtained in Synthesis Example 6 as a ligand were dissolved therein. (7 mg) and 25% aqueous ammonia were added and stirred, but it was confirmed by nuclear magnetic resonance spectrum (NMR) that a nanocomposite composed of dithiolphenyleneethynylene G3-PhE-SH equivalent to Example 4 and gold nanoparticles was not generated. did. Similar results were obtained even when the reaction solvent was changed to toluene.

Preparation of Nanocomposite Thin Film Consisting of G3-PhE-SH and Gold Nanoparticles The nanocomposite obtained in Example 4 was dissolved in toluene and spin coated on a PET film to obtain a thin film. This thin film had the flexibility to bend following the deflection of the PET film.

Conductivity measurement of nanocomposite thin film obtained by compression molding According to the conductivity measurement method, the nanocomposite compression molded thin film obtained in Example 4 was obtained, and the conductivity was measured. The results are shown in Table 1.

Measurement of conductivity of compression-molded nanocomposite thin film doped with iodine The nanocomposite obtained in Example 4 was formed into a compression-molded thin film in the same manner as in Example 6, then subjected to the iodine doping treatment, and measured according to the method of measuring conductivity. The results are shown in Table 1.

Nanocomposite containing semiconductor nanoparticles CdSe nanoparticles and CdSe / ZnS obtained by known hot soap method (high temperature reaction using trioctylphosphine oxide as a ligand) for G3-PhE-SH obtained in Example 3 Nanocomposites can be prepared by mixing with core-shell nanoparticles or semiconductor nanoparticles capable of coordinating thiol groups, such as ZnO nanoparticles obtained by allowing zinc acetate to react with zinc acetate in ethanol. It is. The structure of this nanocomposite is confirmed by SEM observation and NMR as in Example 4.

Synthesis Example 8: Polyphenylene ethynylene having a polybenzyl ether dendrimer side chain and having a thiol terminal The diethynylenebenzene [G-3] 2E2 (1.0 equivalent) to which the third-generation dendrimer synthesized in Synthesis Example 2 was bound 1,4-diiodobenzene (1.0 eq), tetrakis (triphenylphosphine) palladium (0) (0.05 eq) are mixed, and after repeated vacuuming and nitrogen substitution in the glass container, drying is performed. THF was added as a solvent, and a solution prepared by dissolving 2.75 mmol of cuprous iodide in 1000 mL of diisopropylamine was added as cuprous iodide with stirring to 0.05 equivalent. After stirring at 50 ° C. for about 24 hours, a small amount of S-acetyl-4-iodothiophenol obtained in Synthesis Example 1 was added, and the reaction was continued for about 15 hours. The reaction solution was concentrated under reduced pressure, and purified by a reprecipitation method in which the chloroform-soluble component was poured into methanol. This product was soluble in THF, and by measuring the absorption spectrum of this solution, an absorption band derived from a polybenzyl ether dendrimer was observed around 280 nm, and an absorption band derived from a PPhE polymer main chain was observed around 432 nm. The GPC data of this polyphenyleneethynylene having an S-acetyl terminus (hereinafter abbreviated as “S-Ac-PPhE”) were Mn = 14100, Mw = 18100, Mw / Mn = 1.28.

  This S-Ac-PPhE (20 mg) was dissolved in THF (3 mL), sodium hydroxide (49 mg) and water (1 mL) were added thereto, and the mixture was stirred overnight at room temperature. The reaction solution was then concentrated, the residue was extracted with chloroform, the organic phase was washed several times with water, and finally with saturated brine. The residue obtained by concentrating the organic phase is vacuum-dried, dissolved again in chloroform (10 mL), filtered through a 0.25 μm PTFE filter, and concentrated again to give polyphenylene having a polybenzyl ether dendrimer side chain and a thiol end. Ethynylene (hereinafter abbreviated as “SH-PPhE”) was obtained.

(Comparative Example 3)
Composition of thiol-terminated polyphenylene ethynylene and gold nanoparticles The thiol-terminated polyphenylene ethynylene SH-PPhE (20 mg), THF (2.5 mL), and ethanol (0.8 mL) obtained in Synthesis Example 8 are pear types. Placed in flask (25 mL capacity) followed by addition of sodium borohydride (41 mg) and stirred for about 1 hour. Gold nanoparticles (10.6 mg) surface-coated with hexanethiol obtained in Synthesis Example 7 were added together with THF (0.5 mL), and the whole was stirred overnight. Thereafter, the solvent was distilled off under reduced pressure, the reaction product was extracted with chloroform (10 mL), washed with water (10 mL) several times, the resulting chloroform phase was concentrated to about 0.5 mL, and ethanol (20 mL) was added thereto. By pouring, a reactant dispersion was obtained, which was allowed to stand at -20 to -30 ° C to obtain a precipitate. This was collected with a filter and dried to obtain a composition. The conductivity of the nanocomposite thin film obtained by applying this chloroform solution was measured in the same manner as in Example 6. The results are shown in Table 1.

Claims (7)

Phenylene ethynylene represented by the general formula (1).

However, in the general formula (1) R ¹ and R ² is a hydrocarbon residue is a good 10 to 500 carbon atoms which may be different from each other, X is a thiol group, phosphoric acid group, a carboxyl group, a sulfonic acid group, It represents either an amino group or a hydroxyl group, and n represents an integer of 1 to 4. The phenylene ethynylene according to claim 1, wherein either R ¹ or R ² is a dendrimer. A disulfide phenylene ethynylene oligomer represented by the general formula (2).

However, the general formula (2) R ¹ and R ² is a hydrocarbon residue is a good 10 to 500 carbon atoms which may be different from each other, n represents an integer of 1 to 4, p is from 2 to 20 Represents an integer.   The method for producing a phenylene ethynylene according to claim 1 or 2, wherein the disulfide phenylene ethynylene oligomer according to claim 3 is reduced.   A composition comprising the phenyleneethynylenes according to claim 1 or 2 and metal or semiconductor nanoparticles.   6. The composition according to claim 5, comprising a dopant substance capable of interacting with a pi electron conjugated system.   A thin-film shaped article comprising the composition according to claim 5 or 6.