JP2009191152A - HONEYCOMB STRUCTURE COMPRISING DENDRITIC pi-CONJUGATED BASED POLYMER AND METHOD OF MANUFACTURING THE SAME - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a novel approach to obtain a honeycomb structure without chemical modification such as copolymerization with other monomer unit or the formation of derivative by the introduction of side chain by applying Breath Figure method (BF method) to a π-conjugated based polymer such as poly(para-phenylene vinylene). <P>SOLUTION: In the honeycomb structure comprising a dendritic π-conjugated polymer and a method of manufacturing the same, the honeycomb structure comprising π-conjugated polymer is obtained by applying BF method using the π-conjugated polymer having a dendritic structure. A cured material or carbonaceous material having the honeycomb structure is obtained by photocuring or heat-treating a honeycomb structure comprising a dendritic aromatic π-conjugated polymer, particularly dendritic poly(phenylene vinylene). <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to a honeycomb structure made of a dendritic π-conjugated polymer, particularly dendritic poly (phenylene vinylene), and a method for producing the same. The present invention also relates to a cured product having a honeycomb structure excellent in heat resistance and solvent resistance obtained from the structure, and a carbonaceous material having a honeycomb structure.

  In 1994, a honeycomb film (pores were formed from polystyrene-b-polyparaphenylene (PS-b-PP) or star-shaped PS, which is a rod coil type block copolymer, by the Breath Figure method (hereinafter abbreviated as BF method). It was reported that a film regularly opened in a hexagonal shape (see the lower part of FIG. 1) can be produced (see Non-Patent Document 1). The BF method is a method for producing a cast film under high humidity in order to produce a honeycomb structure. Under high humidity, small water droplets are condensed on the cooled organic solvent by evaporating away the heat of vaporization. These water droplets are packed into a hexagonal shape that is energetically stable as the number increases and becomes crowded, and it becomes a mold and finally remains in the form of pores in the polymer film after the organic solvent has evaporated (Fig. (See 1 top). The reason why the small water droplets do not merge when packing is that the water droplets are covered with a thin polymer solution. So far, the pore size of the honeycomb film obtained by the BF method is 150 nm to several tens of μm. The pore size can be controlled by the casting conditions (humidity, polymer concentration, etc.).

  In recent years, in various fields using functional polymer materials ranging from electronics to medicine, it is required to process fine patterns and structures on the surface of the materials. In the field of microfabrication, in addition to the top-down technique such as the conventional photolithography method, various bottom-up techniques utilizing physical properties such as self-organization phenomenon and self-assembly of the material itself are used. Technology has been developed and reported. The application of the above-described BF method has also been studied as one of such bottom-up surface patterning techniques, and a conductive polymer or a light-emitting polymer (for example, non-patented) has been used by the BF method so far. It has been reported that honeycomb films (structures) can be produced from various functional polymers including biodegradable polymers (see, for example, Patent Document 1).

  However, the BF method is based on the premise that an organic solvent that does not mix with water used as a template is used for the casting solution. As organic solvents that do not mix with water, carbon disulfide, chloroform, dichloromethane, toluene, benzene, xylene and the like have been used. On the other hand, since the BF method is a kind of casting method, in principle, it can be applied only to a polymer that is soluble in a solvent. Therefore, it is difficult to apply the BF method as it is for many functional polymers.

  Furthermore, a beautiful honeycomb film is not always obtained just because it dissolves in these solvents. For example, when the solvent is carbon disulfide, it is known that a clean honeycomb film can be obtained with a star-shaped PS, whereas a honeycomb film cannot be obtained when only a linear PS is used. Although the reason is not clearly known, it is empirically known that a clean pattern is easily formed from a rod coil type block copolymer, a star polymer, and an amphiphilic polymer.

  It is known that a π-conjugated polymer has a π electron that spreads along the main chain of the polymer, and thus functions as a conductive polymer or a light-emitting polymer. Examples of such a polymer include polyacetylene, polythiophene, polypyrrole, polyparaphenylene, polyparaphenylene vinylene (PPV), and the like. Since these have the advantage of being lighter and easier to process than metallic electronic materials, their application to lithium ion batteries, aluminum electrolytic capacitors, antistatic films and the like has been put into practical use. In recent years, application of organic EL (Electroluminescence) or organic LED (Light-Emitting Diode) to a light-emitting layer has been studied, and it is expected that a honeycomb film (structure) will be obtained by applying the BF method thereto. ing.

However, a conventional linear π-conjugated polymer, for example, a rigid linear homopolymer having an aromatic ring such as PPV in the main chain skeleton is insoluble in most solvents, and as it is, application of the BF method Is difficult. Up to now, the BF method has been applied to the PPV block copolymerized with PS or the derivative derived by introducing a long alkyl chain for solubilization as a side chain to produce a honeycomb film. (For example, refer nonpatent literatures 2-4). However, since these are not PPVs consisting of pure π-conjugated moieties, the performance and stability as a conductive polymer or a light-emitting polymer may be impaired.
Widawski, G. et al., Nature 369, 387-389 (1994) de Boer, B. et al., Adv. Mater. 12, 1581-1583 (2000) de Boer, B. et al., Polymer 42, 9097-9109 (2001) Govor, LV et al., Adv. Mater. 13, 588-591 (2001) JP 2001-157574 A

  An object of the present invention is to apply a BF method to a π-conjugated polymer such as PPV to obtain a honeycomb structure, such as block copolymerization with other monomer units or derivatization by introducing side chains. To provide a new approach without chemical modification.

  The present inventors have found that a honeycomb structure can be obtained by the BF method by employing a π-conjugated polymer having a dendritic structure instead of the conventional linear one. Furthermore, a honeycomb structure made of a dendritic π-conjugated polymer, particularly an aromatic π-conjugated polymer such as dendritic poly (phenylene vinylene), is subjected to photocuring or heat treatment, thereby maintaining an excellent honeycomb structure. The present inventors have found that a cured product or carbonaceous material having the above characteristics can be provided.

  (1) A honeycomb structure made of a dendritic π-conjugated polymer.

  (2) A hydrophobic organic solvent solution containing a dendritic π-conjugated polymer is cast on a mold or a substrate, held under high humidity, and minute water droplets are condensed on the solution or simultaneously with the condensation. A honeycomb structure obtained by evaporating an organic solvent and removing the fine water droplets.

  (3) The dendritic π-conjugated polymer has the following formula:

The honeycomb structure according to the above (1) or (2), comprising a structural repeating unit of an aromatic π-conjugated system selected from the above.

  (4) The dendritic π-conjugated polymer has the following formula (I):

The honeycomb structure according to any one of the above (1) to (3), which is a dendritic poly (phenylene vinylene) composed of structural repeating units represented by:

  (5) The dendritic π-conjugated polymer is represented by the following formula (Ia) or (Ib):

The honeycomb structure according to any one of the above (1) to (4), which is a dendritic poly (phenylene vinylene) represented by:

  (6) A cured product having a honeycomb structure obtained by photocuring the honeycomb structure according to any one of (1) to (5).

  (7) A carbonaceous material having a honeycomb structure obtained by heat-treating the honeycomb structure according to any one of (1) to (5).

(8) (a) a step of dissolving the dendritic π-conjugated polymer in a hydrophobic organic solvent,
(B) a step of casting the solution obtained in step (a) on a mold or a substrate;
(C) holding under high humidity, condensing fine water droplets on the solution, or evaporating the organic solvent at the same time as condensing; and (d) removing the fine water droplets;
A method for manufacturing a honeycomb structure, comprising:

  The present invention provides a honeycomb structure made of a π-conjugated polymer, which has heretofore been difficult to produce with a linear π-conjugated polymer. The honeycomb structure made of a dendritic π-conjugated polymer of the present invention does not require chemical modification that hinders the conjugated system in the π-conjugated polymer, so that the performance as a conductive polymer or a light-emitting polymer is achieved. And stability is expected.

  Further, since the BF method is applicable only to a polymer soluble in a solvent because of its principle, the honeycomb structure obtained conventionally has a problem of solvent resistance. The honeycomb structure comprising the dendritic π-conjugated polymer of the present invention, particularly a dendritic aromatic π-conjugated polymer such as dendritic poly (phenylene vinylene), is surprisingly subjected to a photocuring treatment. A cured product having an unprecedented solvent structure and excellent honeycomb structure can be provided. The cured product having such a honeycomb structure is expected to be applied to a mold or a filtration membrane that requires solvent resistance.

  Furthermore, since the conventional porous carbonaceous material represented by activated carbon uses the natural material derived from a plant etc. as a raw material, the hole diameter and the arrangement | sequence of the hole were not uniform. In recent years, many attempts have been made to synthesize highly functional porous carbon materials, which require these, but they require a template of a porous material such as zeolite or mesoporous silica, and finally the template is removed. This is a complicated process. On the other hand, according to the present invention, a honeycomb structure composed of a dendritic π-conjugated polymer, especially a dendritic aromatic π-conjugated polymer such as poly (phenylene vinylene), is subjected to heat treatment, and thus is fixed by an extremely simple method. It is possible to provide a porous carbonaceous material having a regular pore size and a regular arrangement.

  The present invention relates to a honeycomb structure made of a dendritic π-conjugated polymer. The honeycomb structure in the present invention is a porous molded product made of a dendritic π-conjugated polymer, and preferably means a thin film (film or sheet-like) and has fine pores (diameter of about 0.1 to 100 μm) means that the honeycomb structure is provided in a regular arrangement in a honeycomb shape, that is, in a honeycomb shape, on at least one surface (plane). The thickness of the thin film is about 0.1 to 100 μm, preferably about 0.1 to 50 μm. The holes may penetrate the film in the vertical direction, and the surrounding holes adjacent to the plane direction and the inside of the film. You may communicate with.

  Examples of the dendritic π-conjugated polymer in the present invention include dendrimers or hyperbranched polymers, which are oligomers or polymers having a dendritic structure in which the branching unit is composed of π-conjugated constituent repeating units. Dendrimers and hyperbranched polymers are distinguished by molecular symmetry and are synthesized with a high degree of symmetry through rigorous reaction operations.They are called dendrimers, and those that show partial asymmetry based on random branches are hyperbranched. It is called a polymer.

  The dendritic π-conjugated polymer of the present invention is a known compound or can be easily produced according to a known method. In general, dendritic polymers (dendrimers or hyperbranched polymers) are synthesized in advance by a divergent method in which molecules are combined for each generation (generation) from the core of the central molecule to the outside. Finally, it can be produced by a known method such as a convergent method of reacting with the core, or a one-step synthesis method using a self-polymerization reaction of ABx type monomers having two types of terminal functional groups A and B that can react with each other. . The former two methods are suitable for synthesizing dendrimers having higher molecular symmetry, and the latter method is suitable for synthesizing hyperbranched polymers that partially exhibit asymmetry.

  When the dendritic π-conjugated polymer of the present invention is a dendrimer, the central molecule (core) may be appropriately selected according to the size, function, etc. of the desired dendritic π-conjugated polymer, and there is no particular limitation. The core may be the same as or different from the π-conjugated repeating unit constituting the branching unit, but is preferably the same as the π-conjugated repeating unit. In the dendritic π-conjugated polymer of the present invention, the structural repeating unit of the π-conjugated system that constitutes the branching unit may be any unit that includes a structural unit of π-conjugated system, such as acetylene, phenylene, thiophene, pyrrole, Examples include phenylene vinylene, phenylene ethynylene, and phenylene butadienylene. Preferably, the following formula:

A structural repeating unit of an aromatic π-conjugated system selected from phenylene, phenylene vinylene, phenylene ethynylene, and phenylene butadienylene, particularly preferably represented by the following formula (I):

It is phenylene vinylene represented by these.

  An example of a dendritic poly (phenylene vinylene), which is a dendritic π-conjugated polymer composed of “phenylene vinylene” units particularly preferred in the present invention, is hyperbranched poly (phenylene vinylene) (hereinafter also referred to as hypPPV), Specific examples include those having a 1,3,5-hypPPV or 1,2,4-hypPPV structure as shown in the following formula (Ia) or (Ib) depending on the substitution position of the phenyl group and the vinyl group. .

The synthesis of these hypPPVs is, for example, a one-step synthesis method using 1-bromo-2,4-divinylbenzene or 1-bromo-3,5-divinylbenzene as AB ₂ monomer according to the method described in the following examples. Can be achieved.

  The weight average molecular weight (Mw) of the dendritic π-conjugated polymer of the present invention is appropriately selected according to the desired characteristics of the honeycomb structure, the solubility of the dendritic π-conjugated polymer used, and the like. It is preferably from 1,000 to 200,000, particularly from about 1,000 to 20,000.

  The honeycomb structure comprising the dendritic π-conjugated polymer of the present invention comprises: (a) a step of dissolving the dendritic π-conjugated polymer in a hydrophobic organic solvent; and (b) a solution obtained in step (a). A step of casting on a mold or a substrate, (c) a step of evaporating the organic solvent after or at the same time as condensing the fine water droplets on the solution, and (d) the fine water droplets. The method can be manufactured according to the method characterized by including the process of removing.

  In the method for manufacturing a honeycomb structure of the present invention, step (a) is a step of preparing a hydrophobic organic solvent solution in which a dendritic π-conjugated polymer is dissolved in a hydrophobic organic solvent. The hydrophobic organic solvent that can be used in the present invention may be any hydrophobic organic solvent as long as it has a degree of hydrophobicity that can retain the water droplets condensed in the step (c). Further, the solvent preferably has a boiling point of 10 to 150 ° C., particularly a temperature of about the same as normal temperature to the boiling point of water under atmospheric pressure, specifically 20 to 70 ° C. Examples of such hydrophobic organic solvents include halogenated hydrocarbons such as carbon tetrachloride, dichloromethane and chloroform, aromatic hydrocarbons such as benzene, toluene and xylene, esters such as ethyl acetate and butyl acetate, and methyl isobutyl. Hydrophobic ketones such as ketones, carbon disulfide and the like can be mentioned, and they are appropriately selected depending on the solubility in the dendritic π-conjugated polymer used.

  The solution may be prepared by dissolving the dendritic π-conjugated polymer so as to be 0.01 to 50 g / L, preferably 1 to 10 g / L with respect to the hydrophobic organic solvent. The concentration can be appropriately determined according to the desired characteristics, physical properties of the honeycomb structure and the solvent used, and may exceed the above range.

  In the method for manufacturing a honeycomb structured body of the present invention, step (b) is a step of casting the solution obtained in step (a) onto a mold or a substrate. The material of the mold or the substrate may be any material generally used for plastic molding by casting, and examples thereof include inorganic materials such as glass and metal, or organic materials having solvent resistance such as polyethylene, polypropylene, and silicone. Can be, but is not limited to. What is necessary is just to select the shape of a type | mold or a board | substrate suitably according to the shape of a desired honeycomb structure. If desired, the surface of the mold or the substrate may be modified according to a known method using a silane coupling agent or the like.

  The method of casting (injecting or casting) the solution obtained in the step (a) onto a mold or a substrate is not only a method of directly injecting or casting the solution, but also a bar coating method, a dip coating method, and a spin coating method. What is necessary is just to select suitably from well-known methods, such as. The cast thickness is appropriately set according to the desired thickness of the honeycomb structure, the concentration of the solution used for casting, and the like, but is preferably in the range of about 1 μm to 10 mm from the viewpoint of the formation efficiency of the holes constituting the honeycomb structure. .

  In the method for manufacturing a honeycomb structure of the present invention, the step (c) is performed after the cast mold or substrate obtained in the step (b) is held under high humidity, and minute water droplets are condensed on the solution. Alternatively, it is a step of condensing and evaporating the organic solvent. Under high humidity means under an atmosphere with a relative humidity of 30% or higher, preferably 50% or higher. The cooling can be performed by the heat of vaporization accompanying the evaporation of the hydrophobic organic solvent. If necessary, the cast mold obtained in step (b) or the substrate itself can be placed in a cool place (however, the freezing point of the solution). You may stand still at the above temperature. Evaporation proceeds almost simultaneously with the condensation of fine water droplets. The substrate or the mold may be kept under high humidity until the evaporation is completed, but may be taken out from the high humidity before the evaporation is completed or after the condensation is completed.

  Evaporation can be performed by natural drying under normal temperature and normal pressure, forced drying by airflow, reduced pressure at which water droplets do not evaporate or forced drying under heating conditions. Properties such as boiling point and volatility of the used hydrophobic organic solvent Although it is appropriately selected according to the above, it is preferable to perform natural drying or forced drying by airflow. Therefore, the step (c) is obtained in the step (b), for example, under an air flow having a relative humidity of 30% or more, preferably 50% or more and a flow rate of 0.1 to 100 L / min, preferably 1 to 50 L / min. The mold or the substrate after casting is allowed to stand, so that fine water droplets are condensed on the solution and at the same time the hydrophobic organic solvent is evaporated. The pore diameter can be adjusted by appropriately setting the conditions such as the relative humidity and the flow rate of the airflow according to the boiling point and volatility of the hydrophobic organic solvent to be used, the concentration and specific gravity of the solution, the cast thickness, and the like.

  In the method for manufacturing a honeycomb structure of the present invention, step (d) is a step of removing the minute water droplets. After evaporation of the hydrophobic organic solvent, water droplets that act as a template and remain in the formed holes may be removed by a known method such as drying under reduced pressure. Next, the mold or the substrate may be removed from the obtained honeycomb structure as desired. The honeycomb structure made of the dendritic π-conjugated polymer of the present invention has appropriate strength and self-supporting property.

  Furthermore, the present invention provides a photopolymerization treatment of a honeycomb structure comprising a dendritic π-conjugated polymer obtained as described above, particularly a dendritic aromatic π-conjugated polymer such as dendritic poly (phenylene vinylene). The present invention also relates to a cured product having a honeycomb structure obtained by attaching. The photocuring treatment can be performed by irradiating the honeycomb structure with UV light having a wavelength of 200 to 400 nm, preferably 250 to 370 nm, for about 2 to 30 minutes, preferably about 2 to 10 minutes. Dendritic aromatic π-conjugated polymers such as dendritic poly (phenylene vinylene) contain many double bonds in their molecular structure, and thus are crosslinked by UV irradiation. The obtained cured product of the present invention has the honeycomb structure as it is, but acquires solvent resistance to various solvents that dissolve dendritic aromatic π-conjugated polymers such as dendritic poly (phenylene vinylene). Can do.

  Furthermore, the present invention provides a honeycomb structure comprising a dendritic π-conjugated polymer obtained as described above, particularly a dendritic aromatic π-conjugated polymer such as dendritic poly (phenylene vinylene), by subjecting it to a heat treatment. The present invention relates to a carbonaceous material having a honeycomb structure. The heat treatment can be performed by subjecting to a thermal decomposition treatment at about 400 to 1200 ° C., preferably about 500 to 700 ° C., under an inert gas atmosphere such as nitrogen. The obtained carbonaceous material maintains the honeycomb structure although the weight and the pore diameter are reduced by about 30 to 50% with respect to the honeycomb structure before processing. Therefore, the honeycomb structure comprising a dendritic aromatic π-conjugated polymer such as dendritic poly (phenylene vinylene) of the present invention is useful as a precursor of a porous carbonaceous material having a constant pore size and a regular arrangement. It is.

  The following examples illustrate the details of the present invention, but these examples are not intended to limit the present invention.

[Synthesis Example] Synthesis of hypPPV
The synthesis of hypPPV was performed according to the following scheme 1 with reference to the description of Macromolecules 39, 9-11 (2006).

[Synthesis Example 1] Synthesis of 1,3,5-hypPPV 1) Synthesis of Compound (2) 10 g of 1-bromo-3,5-dimethylbenzene (1), N-bromosuccinimide (NBS, Tokyo Chemical Industry Co., Ltd.) )) 23 g, azodiisobutyronitrile (AIBN) 50 mg, and CCl ₄ (manufactured by Kanto Chemical Co., Inc.) 250 mL were refluxed for 5 hours. After cooling to room temperature, the solid was removed by filtration. The resulting filtrate was concentrated and the residue was diluted again with 200 mL of dichloromethane. The organic layer was washed twice with saturated Na ₂ CO ₃ solution and twice with distilled water. The organic layer was dried over MgSO ₄ , concentrated and recrystallized from hexane to obtain pure 1,3,5-compound (2) (clear needle crystal, yield 23%).
¹ H NMR (400 MHz, CDCl ₃ ): δ 7.47 (s, 2H), 7.34 (s, 1H), 4.41 (s, 1H)

2) Synthesis of compound (3) A mixture of 3.7 g of 1,3,5-compound (2), 8.6 g of PPh ₃ and 70 mL of benzene was refluxed for 5 hours, cooled to room temperature, and a solid was obtained by filtration. It was. This was washed with diethyl ether and dried in vacuo to give 1,3,5-compound (3) (white powder, 83% yield). This was used in the next step without further purification.
¹ H NMR (400 MHz, CDCl ₃ ): δ 7.83-7.63 (m, 30H), 6.95 (s, 2H), 6.72 (s, 1H), 5.63 (d, 4H, J = 14.6 Hz)

3) Synthesis of Compound (4) A solution of EtOH containing 2.1 g of t-BuOK was slowly added dropwise to a solution of 6.0 g of 1,3,5-compound (3), 1.4 g of formalin and 46 mL of CHCl _3. And stirred at room temperature for 5 hours. The organic layer was washed twice with distilled water, dried over MgSO ₄ , concentrated, and purified by silica gel column chromatography (hexane) to give 1,3,5-compound (4) (clear oil, yield) 48%).
¹ H NMR (400 MHz, CDCl ₃ ): δ 7.44 (s, 2H), 7.31 (s, 1H), 6.64 (dd, 2H, J = 28.4, 6.78 Hz), 5.76 (d, 2H, J = 17.6 Hz ), 5.31 (d, 2H, J = 11.0 Hz)

4) Synthesis of 1,3,5-hypPPV In a flask containing 13 mg of dry Pd (OAc) ₂ and 35 mg of tri-o-tolyl-phosphine, 300 mg of 1,3,5-compound (4) was added under a nitrogen atmosphere. A solution containing 12 mL of DMF (dehydrated) was added followed by 0.5 mL of NEt ₃ (dehydrated). After stirring at 95 ° C. for 6 hours, the mixture was cooled to room temperature and precipitated by adding MeOH. This precipitate was purified by reprecipitation using CHCl ₃ and MeOH to obtain 1,3,5-hypPPV (light brown powder, 15% yield).
¹ H NMR (400 MHz, DMSO): δ 7.9-7.2, 6.79, 5.94, 5.34

The ¹ HNMR, UV-Vis spectrum, and fluorescence spectrum of the obtained 1,3,5-hypPPV coincided with the results of the above-mentioned document (Macromolecules 39, 9-11 (2006)). The molecular weight of 1,3,5-hypPPV obtained from the measurement results of GPC (polystyrene standard sample) was Mn = 1,400, Mw = 1,700, and PDI = 1.2.

[Synthesis Example 2] Synthesis of 1,2,4-hypPPV Synthesis Example 1 except that 1-bromo-2,4-dimethylbenzene was used instead of 1-bromo-3,5-dimethylbenzene as a starting material. 1,2,4-hypPPV was obtained in the same manner as described in 1. The ¹ HNMR, UV-Vis spectrum, and fluorescence spectrum of the obtained 1,2,4-hypPPV agreed with the results of the above-mentioned document (Macromolecules 39, 9-11 (2006)).

Example 1 Production of Honeycomb Film Consisting of 1,3,5-hypPPV 100 μL of 1,3,5-hypPPV chloroform solution (5 mg / mL) obtained in Synthesis Example 1 was applied to a glass substrate (18 mm × 18 mm). A honeycomb film having a thickness of 50 μm (maximum thickness) was produced by spraying moist air previously bubbled in water from 10 cm above at 10 L and evaporating chloroform.

  The hole diameter and its standard deviation were calculated from SEM (Scanning electron microscope, Keyence, VE 7800) photographs of 10 areas randomly selected from two independent samples. SEM photographs were taken at an acceleration voltage of 1.0 kV. Prior to photographing, about 5 nm of Pt was deposited on the sample (JEOL, JFC-1600). The sample was attached to the holder with carbon tape. The optical microscope (OM) image was observed with BX51 (Olympus). The objective lens mainly used 20 times and 40 times. A laser scanning confocal microscope (LSCM) was observed using Lasertech and Keyence (VK-9700).

  An OM and SEM photograph of the obtained honeycomb film are shown in FIG. FIG. 2a shows a film (50 μm × 50 μm) observed by OM. The holes were packed in a close-packed hexagonal shape like a single crystal, and the color of the film was light brown.

  Using SEM or high-performance LSCM, it was possible to clearly observe every single hole (FIG. 2b). From the SEM photograph, the average pore diameter was 860 nm ± 120 nm (mean ± S.D.). Since LSCM scans with a laser, 3D information is obtained. The depth of the hole from LSCM was 1.4 μm.

[Example 2] Production of honeycomb film made of 1,2,4-hypPPV Using 1,2,4-hypPPV obtained in Synthesis Example 2, the thickness of about 50 μm was obtained in the same manner as described in Example 1. A (maximum thickness) honeycomb film was prepared. An SEM photograph of the obtained film is shown in FIG.

[Example 3] Preparation of cured product having honeycomb structure The honeycomb film (1 cm x 1 cm) obtained in Example 1 was irradiated with UV light at 254 nm and 365 nm for 1 to 30 minutes. A xenon light source device (LAX-Cute, Asahi Spectra, Band Pass Filters: UVB300-400 or UVB240-300, Optical Filters: HQBP365-UV or HQBP254-UV) was used for UV light irradiation. During irradiation, the sample was placed 1 cm away from the light source.

  The honeycomb film not irradiated with UV was immediately dissolved in a solvent such as chloroform, dimethylformamide, tetrahydrofuran and the like. On the other hand, the honeycomb film irradiated with UV light having wavelengths of 254 nm and 365 nm for 30 minutes became insoluble in these solvents. When the irradiation time was changed with UV light having a wavelength of 365 nm, most of the honeycomb structure was insoluble in 2 minutes and completely insoluble in 5 minutes. With UV irradiation, the honeycomb structure did not collapse.

[Example 4] Production of a carbonaceous material having a honeycomb structure The honeycomb film (1 cm x 1 cm) obtained in Example 1 was set on an OM with a hot stage (Linkam, THMS 600) and heated in a nitrogen atmosphere. Observed on the spot. The honeycomb structure did not break even when heated to 600 ° C., which is the temperature rise limit of the hot stage (the upper part of FIG. 4). When heated to 600 ° C. and taken out from the hot stage, the film that was originally light brown turned to glossy black and became a carbonaceous film having a honeycomb structure (bottom of FIG. 3). The average diameter of the pores after carbonization was reduced by about 30% to 620 nm ± 80 nm (mean ± SD). Then, as a result of observing with a laser microscope equipped with a hot stage capable of raising the temperature to a higher temperature, it was confirmed that the honeycomb structure was maintained at least up to 680 ° C.

  The thermogravimetric analysis (TGA) of the honeycomb film obtained in Example 1 was measured using a thermal analyzer (Rigaku Thermoplus TG8120) while the heating rate was 3 ° C./min and nitrogen was flowed at 100 mL / min. The TGA curve is shown in FIG. The largest weight loss occurred at around 500 ° C., and thereafter the weight decreased gradually. At 600 ° C., the weight remained at about 60%. As the temperature was raised, film shrinkage was observed in conjunction with weight reduction, but the honeycomb structure was maintained as it was (top of FIG. 4).

  The present invention provides a honeycomb structure made of a π-conjugated polymer, which has heretofore been difficult to produce with a linear π-conjugated polymer. The honeycomb structure made of a dendritic π-conjugated polymer of the present invention does not require chemical modification that hinders the conjugated system in the π-conjugated polymer, so that the performance as a conductive polymer or a light-emitting polymer is achieved. There is expected.

  In addition, a honeycomb structure composed of a dendritic π-conjugated polymer, especially a dendritic aromatic π-conjugated polymer such as dendritic poly (phenylene vinylene) has a high photoreactivity because it has many double bonds, It does not require a photoinitiator and can be subjected to photocuring treatment. By this photo-curing treatment, a cured product having a honeycomb structure with an unprecedented solvent resistance can be provided. The cured product having such a honeycomb structure is expected to be applied to a mold or a filtration membrane that requires solvent resistance. In addition, changes such as the honeycomb structure being broken are not observed even after UV irradiation for a long time. Therefore, the obtained cured product having a honeycomb structure can be further finely processed by standard photolithography.

  Furthermore, the present invention provides a certain simple method for subjecting a honeycomb structure comprising a dendritic π-conjugated polymer, particularly a dendritic aromatic π-conjugated polymer such as dendritic poly (phenylene vinylene), to heat treatment. A porous carbonaceous material having a pore size and a regular arrangement can be provided. This is a new method for synthesizing a porous carbonaceous material without using a solid template, and further application development of the obtained porous carbonaceous material is expected.

The upper part is a schematic diagram of the BF method. The lower row is an example of a honeycomb film. (A) is an OM photograph of the honeycomb film obtained in Example 1, and (b) is an SEM photograph. 4 is a SEM photograph of the honeycomb film obtained in Example 2. The upper row is an OM photograph of the heat change of the honeycomb film obtained in Example 1. The lower left is a photograph of the appearance of the honeycomb film before the heat treatment, and the lower right is the honeycomb film after the heat treatment. 2 is a TGA curve of the honeycomb film obtained in Example 1. FIG.

Claims (8)

  A honeycomb structure comprising a dendritic π-conjugated polymer.   A hydrophobic organic solvent solution containing a dendritic π-conjugated polymer is cast on a mold or a substrate, held under high humidity, and after the minute water droplets are condensed on the solution or at the same time as the condensation, A honeycomb structure obtained by evaporating and then removing the fine water droplets. The dendritic π-conjugated polymer has the following formula:

The honeycomb structure according to claim 1 or 2, comprising a structural repeating unit of an aromatic π-conjugated system selected more. The dendritic π-conjugated polymer has the following formula (I):

The honeycomb structure according to any one of claims 1 to 3, wherein the honeycomb structure is a dendritic poly (phenylene vinylene) composed of a repeating structural unit represented by: The dendritic π-conjugated polymer is represented by the following formula (Ia) or (Ib):

The honeycomb structure according to any one of claims 1 to 4, which is a dendritic poly (phenylene vinylene) represented by:   A cured product having a honeycomb structure obtained by photocuring the honeycomb structure according to any one of claims 1 to 5.   A carbonaceous material having a honeycomb structure obtained by heat-treating the honeycomb structure according to any one of claims 1 to 5. (A) a step of dissolving the dendritic π-conjugated polymer in a hydrophobic organic solvent,
(B) a step of casting the solution obtained in step (a) on a mold or a substrate;
(C) holding under high humidity, condensing fine water droplets on the solution, or evaporating the organic solvent at the same time as condensing; and (d) removing the fine water droplets;
A method for manufacturing a honeycomb structure, comprising: