JP2014108998A - Method of producing carbonaceous material-polymer composite material and carbonaceous material-polymer composition material - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a method of producing a carbonaceous material-polymer composition material being obtainable by a simple process and allowing grafting of a polymer onto the surface diamond or carbon nano-tubes.SOLUTION: A method of producing a carbonaceous material-polymer composite material consisting of diamond or a carbon nano-tube grafted with a polymer includes a step of mixing diamond or a carbon nano-tube with a decomposable monomer whose polymer is decomposed by heating to form a radical and change into the monomer or oligomers or a polymer of the decomposable monomer or a polymer forming a radical near the decomposition temperature to obtain a mixture and a step of putting the mixture in a non-opened container and heating to a first temperature range equal to or higher than the ceiling temperature and equal to or lower than the decomposition initiation temperature.

Description

  The present invention relates to a method for producing a composite material obtained by grafting a polymer to diamond or carbon nanotubes. More specifically, the present invention relates to a depolymerizable monomer, a polymer of the monomer, or a polymer that forms radicals near the decomposition temperature; The present invention relates to a method for producing a composite material obtained by grafting a polymer to diamond or carbon nanotubes by mixing and heating diamond or carbon nanotubes.

  Conventionally, various composite materials of various inorganic materials including carbonaceous materials such as carbon nanotubes and polymers have been proposed. By combining the inorganic material and the polymer, physical properties that cannot be obtained alone can be expressed. As such a composite material, a material obtained by dispersing an inorganic material in a polymer, a material obtained by bonding a polymer to the surface of an inorganic material, and the like are known.

  For example, Patent Document 1 below discloses a method for producing conductive composite fibers containing carbon nanotubes in a high ratio. In this production method, carbon nanotubes are dispersed in a vinyl alcohol homopolymer or copolymer solution in the presence of a stabilizer covalently or non-covalently bonded to the carbon nanotubes to obtain a dispersion. The dispersion is poured into a coagulation solution to form a pre-fiber, and the pre-fiber is dried to obtain a conductive conjugate fiber. As the stabilizer, polyethylene glycol or the like is used, and the polyethylene glycol group is grafted to the nanotube.

  On the other hand, the following Patent Document 2 includes a modified material containing inorganic particles made of a metal hydroxide or an oxide, and a surface modifier connected to the inorganic particles through a urethane bond and having an ethylenically unsaturated end group. Quality inorganic particles are disclosed. Here, the modified inorganic particles are produced by dispersing the modified inorganic particles in a reactive solvent such as styrene or methyl acrylate, and coating the surface of the inorganic particles with a polymer composed of a material constituting the reactive solvent. A method is disclosed.

JP 2010-281024 A JP 2009-138178 A

  Conventionally, various composite materials made by mixing carbonaceous materials such as graphite and carbon nanotubes and polymers have been proposed, but the physical properties are improved because the carbonaceous materials are simply dispersed in the polymer. There was a limit. In the method for producing a conductive conjugate fiber described in Patent Document 1, a polyethylene glycol group or the like derived from the stabilizer is grafted on the surface of the carbon nanotube, whereby a high proportion of the carbon nanotube is contained in the homopolymer or copolymer of polyvinyl alcohol. It is possible to contain. However, even in this method, the carbon nanotubes can only be highly filled in the polymer.

  On the other hand, in the method for producing modified inorganic particles described in Patent Document 2, a surface modifier is bonded to a metal hydroxide or metal oxide surface via a urethane bond, and the ethylenic unsaturation of the surface modifier is performed. End groups and reactive solvents such as styrene and methyl acrylate are bonded by crosslinking. In this method, the bond strength between the inorganic particles and the polymer coating layer comprising a reactive solvent can be increased. However, there are restrictions on the combination of the surface modifier and the reactive solvent for forming the polymer layer. In addition, it has been difficult to control the chain length of the polymer in the obtained polymer layer.

  An object of the present invention is to provide a carbonaceous material-polymer composite material production method capable of grafting various polymers onto the surface of diamond or carbon nanotubes by a simple process, and a carbonaceous material-polymer obtained by the production method. It is to provide a composite material.

  The production method of the present invention is a production method of a carbonaceous material-polymer composite material in which a polymer is grafted to diamond or carbon nanotubes. The polymer is decomposed by heating with diamond or carbon nanotubes to generate radicals and monomers. And a step of mixing a depolymerizable monomer to be oligomerized or a polymer of the monomer, or a polymer that forms a radical near the decomposition temperature to obtain a mixture, and the mixture is placed in a non-open container, and the temperature is higher than the ceiling temperature. And a step of heating above a first temperature range not higher than the decomposition start temperature.

  The step of heating above the first temperature range above the ceiling temperature and below the decomposition start temperature will be abbreviated as A operation as appropriate. In addition, the decomposition start temperature here refers to the temperature at which 10% by weight of the polymer is decomposed when TGDTA measurement is performed in a nitrogen atmosphere. The definition of the ceiling temperature is described in “Radical Polymerization Handbook”, page 112 (issued by NTS).

  In a specific aspect of the method for producing a carbonaceous material-polymer composite material according to the present invention, the polymer is a functional group-containing polymer. In this case, it can introduce | transduce into the material containing the said functional group, and can express the physical property derived from a functional group.

  In another specific aspect of the method for producing a carbonaceous material-polymer composite material according to the present invention, a temperature at which 10% by weight of the polymer is decomposed is a decomposition start temperature, and 90% by weight of the polymer is decomposed. When the temperature is set as the decomposition completion temperature, the heating step includes a step of heating in a second temperature range not less than the decomposition start temperature and not more than the decomposition completion temperature. This heating process is hereinafter abbreviated as B operation. As another form of this method, the method includes a step of repeating the heat treatment in the first temperature range and the second temperature range, and suppresses a polymer graft to diamond or carbon nanotube and a decrease in the molecular weight of the polymer. Enable. The decomposition completion temperature here refers to a temperature at which 90% by weight of the polymer is decomposed when TGDTA measurement is performed in a nitrogen atmosphere.

  In a specific aspect of the method for producing a carbonaceous material-polymer composite material according to the present invention, the heating step may include a step of heating to a third temperature range higher than the decomposition completion temperature. Hereinafter, the process of heating to the third temperature range is abbreviated as C operation as appropriate. Another form of this method includes a case where a medium temperature heating step of heating to a second temperature range below the decomposition completion temperature and a high temperature heating step of heating to a third temperature range higher than the decomposition completion temperature are repeated. Thus, the graft rate can be increased.

  Since the operation A is a temperature region where radical generation due to thermal decomposition occurs slowly, the graft ratio of the polymer is relatively low, but the length of the grafted polymer can be increased.

  Since the B operation is a temperature region in which the thermal decomposition of the polymer is actively caused than the A operation, the graft ratio can be increased.

  Since the C operation is a temperature region in which thermal decomposition is actively caused more than the A and B operations, the number density of graft points can be improved.

  In another specific aspect of the carbonaceous material-polymer composite material according to the present invention, the minimum weight of the decomposition residue in the third temperature range higher than the decomposition completion temperature of the polymer is R, and the polymer in the first temperature range is When the maximum weight of A is A (weight not including adsorbed water, adsorbed gas and solvent), X is the polymer weight at the decomposition start temperature, and Y is the polymer weight at the decomposition completion temperature, the decomposition start temperature is The temperature at which (X−R) / (A−R) = 0.9 is established, and the decomposition completion temperature is the temperature at which (Y−R) / (A−R) = 0.1. As described above, the decomposition start temperature and the decomposition completion temperature are determined according to the above formulas even when a decomposition residue is generated or no decomposition residue is generated when the polymer is heated to the third temperature range. Can be determined. The decomposition start temperature and decomposition completion temperature can be read from the TGDTA measurement under a nitrogen atmosphere.

  Further, in still another specific aspect of the method for producing a carbonaceous material-polymer composite material according to the present invention, as the monomer or polymer, two or more monomers or a mixture of two or more monomers is used as a starting material. When the obtained polymer or a polymer already polymerized is mixed and used, it is possible to read the decomposition start temperature and decomposition end temperature from the TGDTA pattern of this mixture and perform the graft treatment according to the above operating method. .

  Moreover, these several monomers or polymers can also be processed sequentially. In this case, a plurality of types of polymers can be sequentially grafted onto the carbonaceous material. In this case, after grafting with a monomer or polymer having a higher decomposition temperature, the grafting process may be repeated by adding another monomer or polymer having a relatively lower decomposition temperature and mixing them. preferable. By this method, different types of polymers can be grafted onto diamond or carbon nanotubes, and composite materials having various physical properties such as amphiphilic properties can be easily provided.

  In still another specific aspect, carbon dioxide or water in a supercritical state is mixed in the heat treatment.

  In still another specific aspect of the method for producing a carbonaceous material-polymer composite material according to the present invention, the mixture does not contain a polymerization initiator. Even without using a polymerization initiator, according to the present invention, the monomer or polymer can be grafted to diamond or carbon nanotubes by radicals generated by spontaneous decomposition of the polymer.

  Details of the present invention will be described below.

(Carbonaceous material)
In the present invention, diamond or carbon nanotube is used as the carbonaceous material. The surface of a carbonaceous material such as diamond or carbon nanotube has radical trapping properties. Therefore, the polymer comprising the depolymerizable monomer can be grafted with high efficiency according to the production method of the present invention.

(Depolymerizable monomer or polymer of the monomer)
In the production method of the present invention, the diamond or carbon nanotube is mixed with a depolymerizable monomer, a polymer obtained by polymerizing the monomer, or a polymer that forms a radical near the decomposition temperature to obtain a mixture. When this depolymerizable monomer is heated in the first temperature range described above in a non-open container, radicals are spontaneously generated and polymerization proceeds. In addition, the polymerized polymer also undergoes slow depolymerization. Examples of such monomers include polystyrene, polymethyl methacrylate, methyl α-ethyl acrylate, methyl α-benzyl acrylate, methyl α- [2,2-bis (carbomethoxy) ethyl] acrylate, dibutyl itaconate, and itacon. And monomers such as α-substituted acrylic acid ester composed of dimethyl acid, dicyclohexyl itaconate, α-methylene-δ-valerolactone, α-methylstyrene, α-acetoxystyrene.

  A polymer obtained by polymerizing these depolymerizable monomers as raw materials undergoes a slight decomposition reaction in the first temperature range, and undergoes a decomposition reaction in such a manner that the average degree of polymerization decreases in the second temperature range. In the temperature range, the decomposition reaction proceeds to a low molecule close to the monomer as a unit unit of the polymer. A polymer held in such a temperature range in a non-open state will not drop as dramatically as an open system even if the heating time is kept long. This is a phenomenon completely different from the decomposition reaction in an open system. From this phenomenon, it is assumed that radical species are generated continuously because the degree of polymerization does not decrease rapidly by high-temperature heating in a non-open system.

  As the polymer that forms radicals near the decomposition temperature, most organic polymers generate radicals at the decomposition temperature. However, monomers such as ethyl acrylate, butyl acrylate, 2-ethylhexyl acrylate, and benzyl acrylate, and polymers made from them are used as raw materials. Examples include monomers formed by polymerizing vinyl groups such as alkyl (meth) acrylates, polypropylene, polyvinylphenol, polyphenylene sulfide, and polyphenylene ether, and polymers made from such monomers.

  In addition, polymers containing halogen elements such as chlorine such as polyvinyl chloride, chlorinated vinyl chloride, ethylene fluoride resin, vinylidene fluoride, or vinylidene chloride resin can also be used.

  Ethylene vinyl acetate copolymer (EVA), polyvinyl acetal, polyvinyl pyrrolidone and copolymers thereof can also be used.

  Polymers obtained by cationic polymerization such as polyisobutylene and polyalkylene ether can also be used.

  Polyurethane, polyepoxy, modified silicone, silicone resin, etc. made by crosslinking oligomers can also be used.

  When polyallylamine or the like is used, an amino group can be grafted onto the carbon material. When polyvinylphenol or polyphenols are used, phenolic OH can be grafted onto the carbon material. Further, when a polymer having a phosphate group is used, the phosphate group can be grafted.

  Further, in the case of condensation polymers such as polyester and polyamide, the decomposition product is grafted although the radical concentration obtained at the decomposition temperature is low.

  Preferably, the polymer is a functional group-containing polymer. In that case, the functional group can be introduced into the composite material, and physical properties derived from the functional group can be expressed. Such a functional group is not particularly limited, and examples thereof include poval, epoxy group-containing methacrylate resin, poly (meth) acrylic acid, polyhydroxyethyl (meth) acrylic acid and the like. Among these, as the epoxy group-containing methacrylate resin, MMA and GMA (glycidyl methacrylate) copolymers are preferable.

  The first to third temperature ranges will be described with reference to FIG. 1, taking polystyrene as an example. FIG. 1 is a graph showing the relationship between the heating temperature and the relative weight of the polymer when polystyrene is used as the polymer. As shown in FIG. 1, polystyrene hardly decomposes in the first temperature range, but when heated beyond the first temperature range, the weight of the polystyrene decreases, that is, the polymer starts to decompose and generates radicals. . When the temperature exceeds the second temperature range, the decomposition is completed, and polystyrene is decomposed into styrene to be styrene. Moreover, when it cools slowly from the 3rd temperature range over the 2nd temperature range to the 1st temperature range, an unreacted styrene monomer will superpose | polymerize again and will become polystyrene.

  In each temperature range, polystyrene was heated and stored in a closed solution, and the molecular weight decreased due to the high temperature as in the open system. However, even when the heating time was increased, the molecular weight increased more rapidly as the open system. There will be no decline.

  In the present invention, a mixture may be obtained by mixing diamond or carbon nanotubes and the monomer, or a mixture may be obtained by mixing the diamond or carbon nanotubes and a polymer of the monomer. In the above mixing, an appropriate mixing method such as an ultrasonic dispersing device, a homogenizer, a planetary stirrer or the like can be used, and until the heating step described later, it may be mixed at normal pressure, As described later, it is desirable to pressurize under a pressure at which the monomer does not volatilize. Thereby, the volatilization of the monomer can be suppressed, and a sufficient amount of polymer can be grafted onto diamond or carbon nanotube.

  As the gas for applying pressure, carbon dioxide gas or water is preferable. By bringing the pressure to a high pressure with these gases, grafting is possible at a lower temperature than when these gases are not used.

  When the above polymer is used as a raw material, it is desirable to prepare a mixture by kneading the polymer with diamond or carbon nanotubes under heating. Accordingly, the mixture can be plasticized, and the contact probability between the generated diamond or carbon nanotube and the generated radical can be further increased in the heating process.

  The blending ratio of the diamond or carbon nanotube and the monomer is not particularly limited, but it is desirable that the weight ratio is 50-50 to 0.1: 99.9. Moreover, when using the said polymer as a raw material, it is desirable that the mixture ratio of the said diamond or carbon nanotube and the said polymer shall be 50: 50-0.5: 99.5 by weight ratio.

  Two or more monomers or polymers may be used, thereby making it possible to obtain a composite material obtained by combining a plurality of types of polymer alloys with diamond or carbon nanotubes. In this case, two or more types of monomers may be used, two or more types of polymers may be used, and one or more types of monomers and one or more types of polymers may be used.

(Heating process)
In the present invention, when a mixture of a depolymerizable monomer and diamond or carbon nanotube is used as the mixture, the decomposition is in a second temperature region exceeding the ceiling temperature in a non-open container where the monomer does not volatilize. Heat to near start temperature. Accordingly, radicals can be generated and the monomer can be polymerized while suppressing the volatilization of the monomer. The non-open container means a container in which the above-mentioned monomer and polymer decomposition products do not leak out of the container.

  Furthermore, the thermal decomposition radical obtained by decomposition | disassembly is grafted on a diamond or a carbon nanotube by heating more than the decomposition start temperature which is a 2nd temperature range. In this case, the decomposition of the polymer starts not less than the above decomposition start temperature, and the molecular weight of the polymer grafted to diamond or carbon nanotube also decreases.

  By rapidly cooling the reaction system heated at a high temperature, the carbonaceous material-polymer composite material of the present invention in which the polymer is grafted onto diamond or carbon nanotubes can be recovered. Further, when slowly cooled to the first temperature range, the unreacted monomer is polymerized again, so that the ratio of the polymer adsorbed on the diamond or the carbon nanotube can be increased.

  When the polymer is used as a raw material, the polymer is heated to the upper limit of the first temperature range. When the polymer reaches the second temperature range, the polymer starts to decompose, generating radicals, and the active species is It is believed to be grafted to diamond or carbon nanotubes.

  More preferably, a high temperature heating step of heating to a third temperature range higher than the decomposition completion temperature is performed, and then an intermediate temperature heating step of heating to the second temperature range is performed. As a result, a large amount of active radicals are generated from the polymer by thermal decomposition and grafted onto the graphite, but unreacted monomers are polymerized in the subsequent intermediate temperature heating step, and the average chain length of the adsorbed polymer can be increased. Alternatively, the chain length can be further increased by repeating the high temperature heating step and the intermediate temperature heating step.

  Depending on the polymer, a hardly thermally decomposable residue is generated at a temperature higher than the decomposition completion temperature. In this case, the decomposition start temperature and the decomposition completion temperature can be identified as follows. That is, when the weight of the decomposition residue is R, the maximum weight of the polymer in the first temperature range is A, the weight of the polymer at the decomposition start temperature is X, and the weight of the polymer at the decomposition completion temperature is Y, the decomposition start temperature is , (X−R) / (AR) = 0.9, and the decomposition completion temperature is (Y−R) / (A−R) = 0.1.

  As an example, FIG. 2 shows the relationship between the heating temperature and the relative weight of polymethyl methacrylate as a polymer in a system in which a residue after persistent decomposition remains. As shown in FIG. 2, the decomposition rate of the polymer is slow in the first temperature range, but when heated to the second temperature range, the polymer begins to decompose, becomes a monomer, and generates radicals. Furthermore, when heated to the third temperature range, the polymer is decomposed into monomers and decomposition residues. Let R be the relative weight of this decomposition residue. In consideration of the weight R of the decomposition residue, the decomposition start temperature and the decomposition completion temperature may be defined by the above formula.

  In the above formula, R is 0 when no decomposition residue is produced even when the polymer is heated to the third temperature range. Therefore, the above-described equations for determining the decomposition start temperature and the decomposition completion temperature can be applied to a polymer that does not generate a decomposition residue.

  In addition, it is necessary to perform the said heating process under the pressure which a monomer does not volatilize as mentioned above. Under such pressure, depending on the volatility of the monomer used, when using the above-mentioned styrene, (meth) acrylic acid alkyl ester or polypropylene, and also considering the amount of monomer contained in the container and the container, The pressure is preferably 50 mPa or less, and if a container is selected, it is preferably 10 mPa or less. Therefore, the above heating step can be easily performed using an existing pressure vessel.

  Preferably, in order to increase the contact probability between the generated radical and diamond or carbon nanotube, it is also desirable to supply an inert gas during the heating step. Examples of such an inert gas include nitrogen, carbon dioxide gas, and argon gas. Furthermore, it is also desirable to carry out the heating step by supplying a fluid that becomes supercritical by heating to the mixture. Thereby, the contact probability between the generated radical and diamond or carbon nanotube can be further increased. Examples of such a supercritical fluid include carbon dioxide and water that become supercritical by heating and have no radical trapping properties.

  Furthermore, in order to increase the contact probability between the radical and diamond or carbon nanotube, the heat treatment maintained in the second temperature range and the third temperature range may be repeated.

  The carbonaceous material-polymer composite material according to the present invention is obtained by the production method of the present invention.

  According to the method for producing a carbonaceous material-polymer composite material according to the present invention, diamond or carbon nanotubes and the above depolymerizable monomer or polymer of the monomer are mixed and heated to obtain diamond or carbon nanotubes. It is possible to achieve grafting of polymers. Therefore, it is possible to obtain a diamond or carbon nanotube polymer composite material only by controlling the temperature in the heating step, that is, without performing a long graft polymerization step. Moreover, since the diamond or the carbon nanotube of the present invention can be performed in a solvent-free process, the volatile organic compound to be discharged can be reduced.

  In addition, the obtained composite material can be used to graft various polymers, which have been difficult to be grafted, to diamond or carbon nanotubes. In addition, it is possible to graft different types of polymers, and the filler can have a characteristic function such as amphiphilicity.

FIG. 1 is a graph showing the relationship between the heating temperature and the relative weight of the polymer when polystyrene is used as the polymer. FIG. 2 is a graph showing the relationship between the heating temperature and the relative weight of the polymer when polymethyl methacrylate is used as the polymer. FIG. 3 is a diagram showing a TG measurement result of the pretreated CNT obtained in Comparative Example 1. FIG. 4 is a diagram showing a TG measurement result of the solid residue as the CNT-polymer composite material obtained in Example 1. FIG. 5 is a diagram showing a TG measurement result of the CNT-methacrylate resin composite material obtained in Example 2. 6 is a diagram showing the TG / DTA measurement results of the diamond-methacrylate resin composite material obtained in Example 3. FIG.

  Specific examples and comparative examples of the present invention will be described below. In addition, this invention is not limited to a following example.

〔Evaluation method〕
About the Example and comparative example which are mentioned later, it evaluated using either of the following evaluation methods 1) and 2).

Evaluation Method 1): TG / DTA Measurement 2-10 mg of diamond or carbon nanotube was precisely weighed, and TG / DTA was measured using TG / DTA6300 manufactured by SII Nano Technology.

  The initial temperature was 25 ° C., and the temperature was raised to 1000 ° C. at a rate of 10 ° C. per minute.

  The decomposition start temperature, decomposition start temperature, and decomposition completion temperature were measured under a nitrogen gas atmosphere with a gas flow path of 50 ml / min.

  The polymer graft rate was measured under an air atmosphere with a gas flow path of 50 ml / min.

  In addition, when the standard homopolymer was obtained and the decomposition start temperature and the decomposition completion temperature were measured according to the above measurement method, the following results were obtained. However, these values may vary depending on the molecular weight of the polymer.

  The ceiling temperature of polystyrene is reported to be 250 ° C. according to “Radical Polymerization Handbook”, page 112 (issued by NTS, published on September 10, 2010). However, when measured as described above for commercially available polystyrene (manufactured by Wako Pure Chemical Industries, Ltd., trade name: styrene polymer, polymerization degree 2000), the decomposition start temperature was around 350 ° C., and the decomposition completion temperature was around 390 ° C. .

  The ceiling temperature of PMMA is reported to be 155.5 ° C. according to the above literature. When the decomposition start temperature and the decomposition completion temperature were measured according to the above evaluation method (trade name: PMMA, MW 350,000, manufactured by Aldrich), the decomposition start temperature was around 300 ° C. and the decomposition completion temperature was around 350 ° C.

  The decomposition start temperature of polypropylene (manufactured by Nippon Polypro Co., Ltd., trade name: Novatec PP, MA3H) was around 350 ° C., and the decomposition completion temperature was around 400 ° C.

  The decomposition start temperature of polyethylene terephthalate (manufactured by DuPont, trade name: SELAR, PT7001) was around 360 ° C., and the decomposition completion temperature was around 400 ° C. when the residue was heated to 500 ° C. However, the decomposition completion temperature based on the residue when heated to 1000 ° C. was estimated at around 600 ° C. The second temperature range in this case is defined as 360 ° C to 600 ° C.

  The decomposition start temperature and the decomposition completion temperature were measured in a nitrogen gas atmosphere, and the gas flow rate was 50 ml / min.

  The polymer graft ratio was measured under an air gas atmosphere, and the gas flow rate was 50 ml / min.

Evaluation Method 2): Measurement of Polymer Adsorption Rate on Diamond or Carbon Nanotube 1 to 10 g of a sample containing diamond or carbon nanotube subjected to a high-pressure heating reaction treatment is dissolved in a solvent 50 times or more. Dispersion treatment was performed at room temperature for 30 minutes at an output of 45 kHz and 100 W using an ultrasonic device.

  The obtained solution was filtered using a product number PTFE-T300A090C manufactured by Advantech having a hole diameter of 3 μm while suctioning with an aspirator. Further, the same amount of solvent as the amount of the solution was added and filtered again, and the unreacted polymer in the graphene was washed and filtered.

  The sample on the paper was dried in an oven to remove the contained solvent.

  TG / DTA measurement of evaluation method 1) was performed using the sample.

(Comparative Example 1)
As a carbon nanotube (CNT) raw material, product number CM250 manufactured by HANWHA was used.

  In a 500 ml flask, 300 ml of tetrohydrofuran (THF) was added, 30 g of an epoxy group-containing methacrylate resin (manufactured by NOF Corporation, trade name: Marproof G-2050M) was dissolved, and 3 g of the above CNT was further added. This CNT mixture was sonicated. The apparatus was manufactured by Honda Electronics Co., Ltd., W-113 sampler, subjected to ultrasonic treatment for 60 minutes at an output of 100 W and an oscillation frequency of 28 kHz.

  This dispersion solution was dried with a vacuum dryer. The time was 1 hour at room temperature followed by 60 ° C.

  The obtained CNT polymer mixture was pulverized and further dried under reduced pressure by heating.

  The drying temperature condition was 120 ° C. for 1 hour, followed by 150 ° C. for 1 hour.

  The resulting dry CNT mixture was pulverized. Hereinafter, this is referred to as pretreated CNT.

  The obtained mixture was subjected to TG / DTA measurement. The obtained TG measurement results are shown in FIG.

  In a 10 ml vial, 5 g of ethyl acetate and 0.5 g of an epoxy group-containing methacrylate resin (manufactured by NOF Corporation, trade name: Marproof G-2050M) were dissolved, and about 0.1 g of the above pretreated CNTs were mixed.

  After 30 minutes of sonication, a dispersed state was obtained, but a completely black CNT portion settled in 1 hour after standing.

Example 1
Pretreated CNTs were prepared in the same manner as in Comparative Example 1.

  2.5 g of the sample was put into a 5 ml internal volume pipe having a structure capable of bolting both ends of the pipe. Both ends of the pipe were bolted, put into a salt bath set at a temperature of 340 ° C., and left for 120 minutes. The pipe was poured into cold water and cooled. When the bolt was opened after cooling, a black resin mass was obtained.

  This resin mass was dissolved by immersing in 100 ml of THF and subjected to ultrasonic treatment for 30 minutes.

  The CNT dispersion solution was suction filtered, the obtained solid was washed with 100 ml of THF, the residue was vacuum-dried, and TG / DTA measurement was performed. The obtained TG measurement results are shown in FIG.

  When read from FIG. 4, the peak derived from CNT was 34%, and the part attributed to the grafted methacrylate resin was 51%. The graft rate was 60%.

  The obtained residue, that is, the CNT grafted with the methacrylate resin, that is, the CNT-polymer composite material, is very dispersible in the ethyl acetate solvent, and there is no precipitation of CNT even after 6 hours of standing. It was.

(Example 2)
Pretreated CNTs were prepared in the same manner as in Comparative Example 1.

  2.5 g of the sample was put into a 5 ml internal volume pipe having a structure capable of bolting both ends of the pipe. Both ends of the pipe were bolted, put into a salt bath set at 320 ° C., and left for 120 minutes. The pipe was poured into cold water and cooled. When the bolt was opened after cooling, a black resin mass was obtained.

  This resin mass was dissolved by immersing in 100 ml of THF and subjected to ultrasonic treatment for 30 minutes.

  The CNT dispersion solution was subjected to suction filtration, the obtained solid was washed with 100 ml of THF, the residue was dried in vacuo, and TG / DTA measurement was performed. The obtained TG measurement results are shown in FIG.

  When read from FIG. 5, the peak derived from CNT was 75%, and the part attributed to the grafted methacrylate resin was 25%. The graft rate was 25%.

  The obtained residue, that is, the CNT-methacrylate resin composite material, was very dispersible in the ethyl acetate solvent, and CNT did not settle even after 6 hours of standing.

(Example 3)
In 20 ml of THF, 2.02 g of an epoxy group-containing methacrylate resin (manufactured by NOF Corporation, trade name: Marproof G-2050M) is dissolved, and diamond powder (manufactured by Sumiishi Materials Co., Ltd., nano diamond powder) is added to 41. 3 mg was added and sonication was performed for 30 minutes. The dispersion was cast on a fluorinated ethylene resin sheet and dried in a drying oven at 80 ° C. for 2 hours. A sample pipe was prepared in the same manner as in Example 1 except that the diamond-dispersed resin was put in a 7.5 ml internal volume sample pipe, which was put into a sand bath set at a temperature of 340 ° C. for 180 minutes. Heated.

  The obtained pipe was put into cold water and cooled. When the bolt was opened after cooling, a thick gray resin mass was obtained.

  This resin mass was immersed in 100 ml of tetrohydrofuran THF and dissolved. Sonication was performed for 30 minutes to prepare a coarse dispersion solution. The dispersion was taken out and the whole was filtered using PTFE-T100A090C manufactured by Advantech having a hole diameter of 1 μm while suctioning with an aspirator. In order to wash the unreacted methacrylate resin remaining in the residue, the filtration residue was redispersed with 50 ml of THF and refiltered. The filtration residue was heated in a drying oven at 100 ° C., and the remaining solvent was evaporated to dryness.

  TG / DTA measurement was performed on the obtained residue, that is, the diamond-methacrylate resin composite material. The results are shown in FIG.

  When read from FIG. 6, the peak derived from diamond was 97%, and the portion attributed to grafted PMMA was 3%. Therefore, the graft rate was 3%.

Claims (10)

A method for producing a carbonaceous material-polymer composite material in which a polymer is grafted to diamond or carbon nanotubes,
Mixing a diamond or carbon nanotube with a depolymerizable monomer that decomposes a polymer by heating to generate radicals and a monomer or oligomer, or a polymer of the monomer, or a polymer that forms radicals near the decomposition temperature. Obtaining a step;
A method for producing a carbonaceous material-polymer composite material, comprising: placing the mixture in a non-open container and heating the mixture to a first temperature range not lower than a ceiling temperature and not higher than a decomposition start temperature.   The method for producing a carbonaceous material-polymer composite material according to claim 1, wherein the polymer is a functional group-containing polymer.   When the temperature at which 10% by weight of the polymer is decomposed is the decomposition start temperature, and the temperature at which 90% by weight of the polymer is decomposed is the decomposition completion temperature, the decomposition is completed at the decomposition start temperature or more in the heating step. The manufacturing method of the carbonaceous material-polymer composite material of Claim 1 or 2 further equipped with the heating process heated to the 2nd temperature range below temperature.   The method for producing a carbonaceous material-polymer composite material according to any one of claims 1 to 3, further comprising a heating step of heating to a third temperature range higher than the decomposition completion temperature in the heating step.   The manufacturing method of the carbonaceous material-polymer composite material of Claim 4 which repeats the heating process heated to the said 2nd temperature range, and the heating process heated to the said 3rd temperature range.   The weight of the decomposition residue at a temperature higher than the decomposition completion temperature of the polymer is R, the maximum weight of the polymer in the first temperature range is A (weight not including adsorbed water, adsorbed gas, and contained solvent), and the decomposition start temperature. When the weight of the polymer is X and the weight of the polymer at the decomposition completion temperature is Y, the decomposition start temperature is a temperature at which (X−R) / (A−R) = 0.9, and the decomposition completion temperature The manufacturing method of the carbonaceous material-polymer composite material of any one of Claims 1-5 which is the temperature which is (YR) / (AR) = 0.1.   The method for producing a carbonaceous material-polymer composite material according to any one of claims 1 to 6, wherein two or more monomers or polymers are used as the monomer or polymer.   The method for producing a carbonaceous material-polymer composite material according to any one of claims 1 to 7, wherein carbon dioxide or water in a supercritical state is mixed in the heat treatment.   The method for producing a carbonaceous material-polymer composite material according to any one of claims 1 to 8, wherein the mixture does not contain a polymerization initiator.   A carbonaceous material-polymer composite material obtained by the production method according to claim 1.

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