CN104744728A - Method for crystallizing and coating polymer on carbon-based nano material surface - Google Patents
Method for crystallizing and coating polymer on carbon-based nano material surface Download PDFInfo
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Abstract
The invention discloses a method for crystallizing and coating polymer on a carbon-based nano material surface. The method comprises the following steps: (1) adding carbon-based nano powder and an organic solvent into a reaction container, performing ultrasonic treatment at 5-35 DEG C to obtain a dispersion fluid; adding polymer monomer and an alpha-diimine palladium catalyst into the dispersion fluid and continuously reacting for a certain time at 5-40 DEGC through stirring or ultrasonic field action to obtain a reaction product, wherein the polymer monomer is alicyclic-ring olefin; (2) centrifuging or performing vacuum suction on the reaction product obtained in the step (1) to remove residues of excessive polymer monomer and the alpha-diimine palladium catalyst, and drying to obtain the carbon-based nano powder, surface of which is crystallized and coated with polymer. According to the method, in-situ synthesis of hypocrystalline polymer and an induced crystallization process of the hypocrystalline polymer on the carbon-based nano material surface are synchronously completed, and the method has the advantages of being gentle in condition, simple in process, wide in scope of application, and the like.
Description
Technical Field
The invention relates to a non-covalent coating modification method for a polymer on the surface of a carbon-based nano material.
Background
Carbon-based nanomaterials (including C60, carbon nanotubes and graphene, corresponding to 0, 1 and 2 dimensional structures, respectively), all sp2Hybridized carbon atomThe structure has been a hot material in the field of nano-material research in recent years. The carbon nano tube and the graphene respectively have unique one-dimensional and two-dimensional structures, show excellent performances such as electric conduction, heat conduction, mechanics and optics, and have wide application prospects in the fields of energy conversion and storage, advanced composite materials, photoelectric devices and the like.
However, to realize the application of carbon nanotubes and graphene in the above-mentioned fields, the following problems must be solved first: firstly, high-concentration stable dispersion of carbon nanotubes or graphene in a specific medium is realized; secondly, introducing a required functional group on the surface of the graphene or the carbon nano tube to realize surface functional modification; and thirdly, modifying the surface of the graphene or the carbon nano tube to promote the uniform dispersion of the graphene or the carbon nano tube in various matrixes and obtain a strong interface effect.
The modification of the surface of graphene (carbon nanotubes) with an organic polymer (hereinafter referred to as "polymer") is an effective way to solve the above problems. To date, a series of techniques for graphene (carbon nanotube) surface polymer modification have been reported. According to the nature of the polymer and graphene (carbon nanotube) surface interaction, two broad categories can be divided into covalent method and non-covalent method. In the concept of covalent method, polymer molecular chains with specific structures can be covalently grafted on the surface of graphene (carbon nano tube) by the technologies of grafting to, grafting from or coupling reaction and the like; the method has the advantages that: the polymer is firmly combined with the surface of the graphene (carbon nano tube), but the structure of the graphene (carbon nano tube) is easy to be damaged in the modification process, so that the conductivity of the graphene (carbon nano tube) is obviously reduced. In the non-covalent method, the non-covalent grafting of the polymer on the surface of the graphene (carbon nano tube) is realized mainly by utilizing various non-covalent actions (typical actions such as pi-pi stacking action, CH-pi action, electrostatic action, charge transfer action, hydrophilic-lipophilic action and the like) of the polymer and the surface of the graphene (carbon nano tube); the method has the advantages that the original structural integrity and performance advantages of graphene (carbon nano tube) can be effectively retained in the modification process, but the surface effect of the polymer and the graphene (carbon nano tube) is weak, and the interface structure is unstable.
In the presence of graphene (carbon nano tube), based on the principle of in-situ induced crystallization, the semi-crystalline polymer can be subjected to in-situ induced crystallization on the surface of the former polymer, and the graphene (carbon nano tube) hybrid material coated by the polymer crystal on the surface is obtained. In the special non-covalent modification method, the polymer crystal layer formed on the surface of the graphene (carbon nano tube) has stable structure and more stable interface action compared with the interface action obtained by other non-covalent methods; meanwhile, the crystallization condition is selected and controlled, the crystallization form of the polymer on the surface of the graphene (carbon nano tube) can be effectively regulated, and a specific functional group can be introduced to the surface of the graphene (carbon nano tube) through the design of the structure and the composition of the polymer, so that various functional applications of the graphene (carbon nano tube) are realized. Related researches have been reported in many documents so far, but the following defects still exist in summary: (1) the modification process is generally carried out in two steps, firstly semi-crystalline polymers such as polyethylene, nylon, polyacrylonitrile and the like are obtained through synthesis, and then the polymers are slowly precipitated in a solution system containing graphene (carbon nano tubes) to realize the surface induced crystallization of the polymers; (2) the crystallization conditions required in the induced crystallization process are harsh, and for example, the crystallization process of solution precipitation needs to be performed at a constant temperature for a long time. The above features are not conducive to scale application of the technology.
Therefore, how to realize the induced crystallization coating of the semi-crystalline polymer on the surface of the graphene (carbon nano tube) by simple process steps under mild conditions to promote various applications of the carbon-based nano material still remains an important technical problem to be solved in the field.
Disclosure of Invention
The invention aims to provide a carbon-based nano material surface polymer induced crystallization coating method, in the method, the in-situ synthesis of a semi-crystalline polymer and the induced crystallization process of the semi-crystalline polymer on the surface of the carbon-based nano material are synchronously completed, and the method has the advantages of mild conditions, simple process, wide application range and the like.
The technical solution adopted by the present invention is specifically explained below.
A method for coating a polymer on the surface of a carbon-based nano material by induced crystallization specifically comprises the following steps:
(1) adding carbon-based nano powder and an organic solvent into a reaction container, and obtaining a dispersion liquid by ultrasonic treatment at 5-35 ℃; further adding a polymerization monomer and a Pd-diimine palladium (Pd-diimine) catalyst into the dispersion liquid, and then continuously reacting for a certain time under the action of a stirring or ultrasonic field at 5-40 ℃ to obtain a reaction product; the organic solvent adopts one of the following analytically pure or chemically pure solvents: chlorobenzene, dichloromethane, trichloromethane; the polymerized monomer adopts alicyclic olefin;
(2) and (2) carrying out centrifugation or vacuum filtration on the reaction product obtained in the step (1) to remove redundant polymerized monomers and residues of the alpha-diimine palladium catalyst, and drying to obtain carbon-based nano powder coated with surface polymer crystals.
The carbon-based nano powder can adopt carbon nano tube powder with different specifications and surface properties, namely the carbon nano tube with the unmodified surface and the carbon nano tube with the chemically modified surface are both suitable, and one of the following sources can be specifically adopted: the surface of the single-arm carbon nano tube is not chemically modified, the surface of the multi-arm carbon nano tube is not chemically modified, the surface of the single-arm carbon nano tube is chemically modified, and the surface of the multi-arm carbon nano tube is chemically modified; the length of the carbon nano tube is controlled to be 0.1-500 mu m, preferably 0.1-100 mu m; the inner diameter of the carbon nanotube is controlled to be 2-30 nm, the outer diameter is controlled to be 5-100 nm, and the inner diameter is preferably 5-20 nm, and the outer diameter is preferably 10-50 nm. The purity of the carbon nano tube is controlled to be 50-100%, and preferably 80-100%; the specific surface area of the carbon nano tube is controlled to be 50-500 m2A concentration of 100 to 400m is preferred2/g。
The carbon-based nano powder can also adopt graphene powder with various specifications and surface properties, and specifically can adopt one of the following sources: graphene prepared by mechanical exfoliation, graphene prepared by chemical oxidation-reduction, graphene obtained by CVD, graphene obtained by chemical synthesis, and graphene obtained by various other possible methods; the surface of the graphene can be modified by a chemical method or not; the thickness of the graphene is controlled to be 1-10 layers, and 1-5 layers are preferred; the transverse size of the graphene is controlled to be 0.1-100 mu m, and preferably 0.2-50 mu m.
The organic solvent in the step (1) may be one of the following analytically pure or chemically pure solvents: chlorobenzene, dichloromethane, trichloromethane, preferably trichloromethane or dichloromethane.
The reaction vessel in the step (1) may be a glass vessel of various shapes or specifications, and specifically may be one of the following: test tube, column glass bottle, three-neck flask, single-neck flask, Schlenk reaction flask, beaker. The volume of the reaction container is controlled to be 0.005-20L, preferably 0.01-5L.
The dispersion liquid in the step (1) can be prepared by ultrasonic treatment, wherein the ultrasonic temperature is controlled to be 5-35 ℃, and preferably 15-30 ℃; controlling the ultrasonic power to be 25-300W, preferably 50-250W; the ultrasonic time is controlled to be 0.5-8 h, preferably 0.5-5 h.
The polymerized monomer in the step (1) can adopt various alicyclic olefins, and can be specifically selected from one of the following: cyclopropene, cyclobutene, cyclopentene, cyclohexene, cycloheptene.
The catalyst in the step (1) adopts an alpha-diimine palladium (Pd-diimine) catalyst, which can be selected from one of the following catalysts: an acetonitrile group Pd-diimine catalyst (denoted as catalyst 1) shown in formula (1), a cyclic Pd-diimine catalyst (denoted as catalyst 2) shown in formula (2) and containing a methyl ester group, and a cyclic Pd-diimine catalyst (denoted as catalyst 3) shown in formula (3) and containing isobutyryl bromide:
the above catalysts 1-3 can all be synthesized in the laboratory with reference to the following documents:
[1]Johnson L.K.,Killian C.M.,Brookhart M.J.Am.Chem.Soc.,1995,117,6414；[2]JohnsonL.K.,Mecking S.,Brookhart M.J.Am.Chem.Soc.,1996,118,267；[3]Zhang K.,Ye Z.andSubramanian R.Macromolecules,2008,41,640.
the polymerization reaction in the step (1) is carried out at a constant temperature, the temperature is controlled to be 5-40 ℃, the preferred temperature is 15-35 ℃, and the total polymerization reaction time is controlled to be 0.5-200 h, the preferred time is 2-120 h; the polymerization reaction can be carried out under the magnetic stirring or mechanical stirring of a constant speed, the stirring speed is controlled between 50 rpm and 1000rpm, preferably 100 rpm to 500rpm, the polymerization reaction can also be carried out under the action of an ultrasonic field, and the ultrasonic power is controlled between 50W and 500W, preferably 50W to 300W.
In the polymerization reaction system in the step (1), the feeding concentration of the carbon-based nano powder is controlled to be 0.001-100 mg/mL, preferably 0.005-50 mg/mL; the feeding amount of the polymerization monomer is controlled to be 1.0 multiplied by 10 per 1mg of carbon-based nano powder-5About 20mol, preferably adding 1.0X 10-410mol to 10 mol; the dosage of the alpha-diimine palladium catalyst is controlled to be 1.0 multiplied by 10 added per 1mg of carbon-based nano powder-5About 1.0mmol, preferably 1.0X 10-4～0.1mmol。
The polymerization reaction in the step (1) is carried out under the protection of inert atmosphere, and one of the following inert atmospheres can be adopted: nitrogen, helium, argon, preferably nitrogen.
The purification of the reaction product in the step (2) can be carried out by a centrifugal method, wherein the centrifugal speed is controlled to be 2000-15000 rpm, preferably 3000-10000 rpm; the centrifugation time is controlled to be 5 min-2 h, preferably 10 min-1 h; in order to remove the residue of the incompletely reacted polymerized monomer and catalyst in the product, the obtained centrifugal product can be dispersed in the corresponding fresh organic solvent again, and centrifuged again under the same centrifugal condition, and the washing process can be repeated for a plurality of times as required.
The reaction product in the step (2) can be purified by a vacuum filtration method, and the average pore diameter of a required filter membrane is 0.01-0.5 μm, preferably 0.02-0.25 μm; the membrane material can be selected from one of polytetrafluoroethylene, polyvinylidene fluoride or alumina; in order to remove the incompletely reacted polymerized monomers and catalyst residues from the product, the resulting filtered product may be further rinsed with a corresponding fresh organic solvent several times.
After the reaction product in the step (2) is purified, the drying of the obtained product can be carried out according to the following process: vacuum drying at room temperature to 80 ℃ for 0.5 to 48 hours; the preferred process comprises the following steps: the temperature is between room temperature and 50 ℃, and the time is 0.5 to 8 hours.
The surface polymer crystal coated carbon-based nano powder prepared by the invention can be further used for preparing various high-performance polymer/carbon nano tubes or polymer/graphene composite materials.
Compared with the prior art, the invention has the following outstanding advantages and beneficial effects:
first, in the present invention, the synthesis of semicrystalline polymer and its induced crystallization on the surface of carbon-based nanopowder are simultaneously completed, while in the same technology, it is usually necessary to synthesize the polymer in advance and then induce the crystallization of the polymer on the surface of carbon nanopowder under strictly controlled conditions. Thus, the present invention requires fewer process steps than the same technology.
Secondly, in the present invention, the in-situ synthesis of the polymer and the induced crystallization thereof on the surface of the carbon nanopowder can be carried out at a relatively mild temperature, and the applicable temperature range is wide, whereas in the same kind of technologies, the in-situ synthesis of the polymer and the induced crystallization thereof can be realized only under the conditions of a higher temperature and a strict constant temperature, so that the technology has the advantages of simpler process control and milder conditions.
Thirdly, the polymer crystallization coating technology provided by the invention is not only suitable for various one-dimensional carbon nanotube powders, but also suitable for various two-dimensional graphene powders, and the polymer crystallization coating structure on the surface of the carbon nanotube powder can be conveniently and effectively regulated and controlled through process control, so that the technology has the advantages of wide application range and controllable product structure.
Fourth, in the present invention, the polymer crystal coating layer formed on the surface of the carbon nano-powder can resist higher temperature, and can resist various organic solvents to keep stable structure, which is helpful for further functional treatment and related applications of the obtained composite powder.
Drawings
FIG. 1 is a process flow diagram of a coating method of in-situ induced crystallization of a polymer on the surface of carbon-based nanopowder according to the present invention;
FIG. 2 is a transmission electron microscope photograph of the samples obtained in comparative example 1 and example 1: (a) comparative example 1; (b) example 1;
FIG. 3: (a) is a transmission electron micrograph of the sample obtained in comparative example 2; (b) is a transmission electron micrograph of the sample obtained in example 2; (c) is a scanning electron micrograph of the sample obtained in comparative example 2; (d) is a scanning electron micrograph of the sample obtained in example 2;
FIG. 4 is a transmission electron microscope photograph of samples obtained in comparative example 3 and example 3: (a) comparative example 3; (b) example 3; (c) comparative example 3; (d) example 3;
FIG. 5: (a) and (b) is a TEM image of the sample obtained in example 4; (c) TGA profiles of the samples obtained in example 4 and comparative example 4;
FIG. 6 is a TEM picture of the samples obtained in comparative example 5 and example 5: (a) comparative example 5; (b-d) example 5;
fig. 7 is a TEM picture of samples obtained in comparative example 6 and example 6: (a) comparative example 6; (b) example 6;
FIG. 8 is a TEM picture of the samples obtained in comparative example 6 and example 7: (a) comparative example 6; (b) example 7;
FIG. 9 is a TEM picture of the samples obtained in comparative example 7 and example 8: (a) comparative example 7; (b) example 8.
Detailed Description
The present invention will be described in further detail with reference to the following examples and drawings, but the embodiments of the present invention are not limited thereto.
Example 1 and comparative example 1
1. Preparation of samples
(1) Example 1
Step 1: under the protection of nitrogen, 150mg (feeding concentration: 5mg/mL) of multi-arm carbon nano-tubes (MWCNTs, product of Chinese institute of organic chemistry, purity 95%, average outer diameter about 30nm, average inner diameter about 10nm, average length 30-50 μm, specific surface area 233m2/g) was added to a Schlenk reaction flask of 50mL size together with 24mL of anhydrous dichloromethane, and the initial dispersion of MWCNTs was obtained by sonication (power 75W, time 2h) at room temperature; 6mL of a polymerization monomer cyclopentene (4.76g, charge concentration 4.67X 10) was further added to the obtained dispersion－4mol/mg MWCNTs) and 50mg Pd-diimine catalyst 3 (the feeding concentration is 3.2 multiplied by 10)-4mmol/mg MWCNTs), followed by a reaction continued for 8h at constant temperature (25 ℃) and magnetic stirring speed (200rpm) to obtain the reaction product.
Step 2: and (3) centrifuging the reaction product obtained in the step 1 (9000rpm, 15min), removing the upper solution, collecting the lower product, performing ultrasonic washing by using fresh dichloromethane solvent (40mL), performing centrifugal separation again, repeating the washing step for 3 times, and performing vacuum drying on the obtained product at room temperature for 8 hours to obtain the final product.
(2) Comparative example 1
Comparative analyses were performed directly using the starting MWCNTs feedstock used for the preparation of sample 1 above.
2. Characterization and testing
Transmission Electron Microscope (TEM) analysis was carried out on a high-resolution transmission electron microscope (acceleration voltage 300kV) of the type Tecnai G2F30S-Twin, manufactured by Philips-FEI, the Netherlands. A small sample (about 5mg) was ultrasonically dispersed in Tetrahydrofuran (THF) and then a small amount of the resulting suspension was dropped onto the copper mesh surface (containing the porous carbon support film) and allowed to evaporate for analysis.
3. Result comparison and analysis
Fig. 2 compares the high resolution TEM results of the corresponding samples of example 1 and comparative example 1. In which FIG. 2(a) corresponds to comparative example 1, the sample is MWCNTs raw material which is not modified by polymer surface coating, as shown in the figure, MWCNTs before modification have smooth surface, outer diameter of about 30nm and inner diameter of about 10 nm. FIG. 2(b) corresponds to example 1, in which the MWCNTs surface has been polymerized at room temperature for 8h with cyclopentene monomer catalyzed by Pd-diimine catalyst 3, as shown in the figure, the resulting MWCNTs surface becomes significantly rougher than before modification, with a polymer coating layer similar to a shark skin (shown as white circles in the figure). The above results confirm that: by utilizing the process, the semi-crystalline polycyclopentene can be crystallized and coated on the surface of the MWCNTs, and the MWCNTs hybrid material coated by the polycyclopentene crystals on the surface is obtained.
Example 2 and comparative example 2
1. Preparation of samples
(1) Example 2
Step 1: under the protection of nitrogen, 150mg (feeding concentration: 5mg/mL) of multi-arm carbon nano-tubes (MWCNTs, product of Chinese institute of organic chemistry, purity 95%, average outer diameter about 30nm, average inner diameter about 10nm, average length 30-50 μm, specific surface area 233m2/g) was added to a Schlenk reaction flask of 50mL size together with 24mL of anhydrous dichloromethane, and the initial dispersion of MWCNTs was obtained by sonication (power 75W, time 2h) at room temperature; further, 6mL of the resulting dispersion was addedPolymerization of monomeric cyclopentene (4.76g, charge concentration 4.67X 10－4mol/mg MWCNTs) and 100mg Pd-diimine catalyst 3 (the feeding concentration is 6.4 multiplied by 10)-4mmol/mg MWCNTs), followed by a reaction continued for 4h at constant temperature (25 ℃) and magnetic stirring speed (200rpm) to obtain the reaction product.
Step 2: and (3) centrifuging the reaction product obtained in the step 1 (9000rpm, 15min), removing the upper solution, collecting the lower product, performing ultrasonic washing by using fresh dichloromethane solvent (40mL), performing centrifugal separation again, repeating the washing step for 3 times, and performing vacuum drying on the obtained product at room temperature for 8 hours to obtain the final product.
(2) Comparative example 2
The only difference is that the polymerization time is changed from 4h to 2h, as described above in connection with example 2.
2. Characterization and testing
(1) TEM analysis
Refer to example 1 and comparative example 1.
(2) Scanning Electron Microscope (SEM) analysis
The test was carried out on a scanning electron microscope of HITACHIS-4700 type manufactured by Hitachi, Japan. A small amount of samples are uniformly laid on the surface of a sample table (fixed by conductive adhesive), and the samples are analyzed after gold spraying on the surface.
3. Result comparison and analysis
FIG. 3 compares TEM and SEM results for samples corresponding to example 2 and comparative example 2. In both the embodiment 2 and the comparative example 2, the MWCNTs are subjected to surface polymer crystallization coating modification by adopting the process method disclosed by the invention, and the adopted process parameters are consistent except for different polymerization time. Of these, comparative example 2 corresponds to a shorter polymerization time (2h), while example 2 corresponds to a longer polymerization time (4 h). FIG. 3(a) is a TEM image of a sample corresponding to comparative example 2 (polymerization time 2h), showing that the resulting MWCNTs sample has a very low proportion of surface polymers, substantially similar to the surface state before modification; FIG. 3(b) TEM image corresponding to example 2 (polymerization time 4h) shows that the surface polymer ratio of the resulting MWCNTs is significantly increased with the extension of the polymerization time to 4h, and the overall MWCNTs are in a uniform wrapped state. Fig. 3(c) and (d) correspond to SEM results of the above two samples, respectively, and similar conclusions can be obtained by comparison. The above results show that: the polymerization process can realize the crystallization coating of the polycyclopentene on the surface of the MWCNTs, and meanwhile, the polymer coating proportion on the surface of the carbon tube can be effectively regulated and controlled through the change of the polymerization time.
Example 3 and comparative example 3
1. Preparation of samples
(1) Example 3
Step 1: under the protection of nitrogen, 150mg (feeding concentration: 5mg/mL) of multi-arm carbon nano-tubes (MWCNTs, product of Chinese institute of organic chemistry, purity 95%, average outer diameter about 30nm, average inner diameter about 10nm, average length 30-50 μm, specific surface area 233m2/g) was added to a Schlenk reaction flask of 50mL size together with 24mL of anhydrous dichloromethane, and the initial dispersion of MWCNTs was obtained by sonication (power 75W, time 2h) at room temperature; 6mL of a polymerization monomer cyclopentene (4.76g, charge concentration 4.67X 10) was further added to the obtained dispersion－4mol/mg MWCNTs) and 75mg Pd-diimine catalyst 3 (the feeding concentration is 4.8 multiplied by 10)-4mmol/mg MWCNTs), followed by a reaction continued for 8h at constant temperature (25 ℃) and magnetic stirring speed (200rpm) to obtain the reaction product.
Step 2: and (3) centrifuging the reaction product obtained in the step 1 (8000rpm, 20min), removing an upper layer solution, collecting a lower layer product, performing ultrasonic washing by using a fresh dichloromethane solvent (40mL), performing centrifugal separation again, repeating the washing step for 3 times, and performing vacuum drying on the obtained product at room temperature for 8 hours to obtain a final product.
(2) Comparative example 2
With reference to example 3 above, the only difference is that: catalyst 3 adopts a lower feeding concentration (1.6 multiplied by 10)-4mmol/mg MWCNTs)。
2. Characterization and testing
TEM analysis was performed with reference to example 1 and comparative example 1.
3. Result comparison and analysis
FIG. 4 compares TEM results of samples corresponding to example 3 and comparative example 3. In both example 3 and comparative example 3, the process of the present invention is used to perform the coating modification of the surface of MWCNTs by the polycyclopentene crystallization, and all the process parameters are consistent except for the use of different catalyst feeding concentrations. Wherein the catalyst charge concentration used in example 3 was 4.67X 10－4mol/g MWCNTs, while comparative example 3 uses a lower catalyst charge concentration (1.6X 10)-4mmol/mg MWCNTs). FIGS. 4(a) and (c), which correspond to comparative example 3, show that the resulting MWCNTs surface polymer failed to form a continuous coating due to the lower catalyst concentration. Further, as can be seen from fig. 4(b) and (d), in example 3, due to the increased catalyst charge concentration, the degree of polymer crystal coating on the surface of the MWCNTs is significantly increased, forming a continuous polymer coating layer, and the polymer coating thickness is significantly increased compared to comparative example 3. The method shows that the MWCNTs surface can be crystallized and coated by the polycyclopentene through the process, and meanwhile, the coating degree and the coating form of the carbon tube surface polymer can be effectively adjusted by changing the feeding concentration of the catalyst.
Example 4 and comparative example 4
1. Preparation of samples
(1) Example 4
Step 1: under the protection of nitrogen, 50mg (feeding concentration: 2.2mg/mL) of multi-arm carbon nano-tubes (MWCNTs, Sigma-Aldrich product, purity is 90 percent, average outer diameter is about 10-15 nm, average inner diameter is about 2-6 nm, and average length is 0.1-10 nmμ m, specific surface area 255m2/g) was added to a 30mL glass tube together with 20mL of anhydrous dichloromethane and the initial dispersion of MWCNTs was obtained by sonication (power 70W, time 2h) at room temperature; to the resulting dispersion was further added 3mL of a polymerization monomer cyclopentene (2.31g, charge concentration 4.67X 10)－4mol/mg MWCNTs) and 25mg Pd-diimine catalyst 1 (feed concentration 6.2X 10)-4mmol/mg MWCNTs), followed by a reaction continued at constant temperature (25 ℃) and magnetic stirring speed (500rpm) for 72h to obtain the reaction product.
Step 2: and (2) carrying out vacuum filtration on the reaction product obtained in the step 1, adopting a polyvinylidene fluoride filter membrane with the average pore diameter of 0.22 mu m, leaching the product for multiple times by using a fresh dichloromethane solvent (100mL) after filtration, and further carrying out vacuum drying for 8 hours at room temperature to obtain a final product.
(2) Comparative example 2
The MWCNTs starting material from example 4 above was used directly.
2. Characterization and testing
(1) TEM analysis
Reference is made to example 1 and comparative example 1.
(2) Thermogravimetric analysis (TGA)
The test was carried out on a thermogravimetric analyzer model Q50, manufactured by TA, in a nitrogen atmosphere, with a sample dose of about 5 mg; and (3) testing procedures: the temperature is rapidly increased to 100 ℃, the temperature is kept constant for 10min, and then the temperature is increased to 800 ℃ at the constant speed of 20 ℃/min.
3. Result comparison and analysis
Unlike the previous examples 1-3, in this example 4, MWCNTs of another specification (produced by Sigma-Aldrich, having smaller inner and outer diameters) were used as the starting material, and another Pd-diimine catalyst 1 was used, and cyclopentene was used as the polymerization monomer, and the surface of MWCNTs was coated and modified by the process of the present invention. TEM results of the resulting composite are shown in FIG. 5 (a-b). The graph shows that the MWCNTs surface has obvious polymer coating structures after being modified, and the polymer coating thickness is uniform from the overall view, and the surface has a shark skin-shaped appearance. Further, the TGA curve of this composite material is given in fig. 5(c), and for comparison, the TGA result of comparative example 5 (corresponding to the MWCNTs starting material before modification) is also given. As shown in the figure, the weight loss rate of the MWCNTs sample before modification at 600 ℃ is only 1.2%, resulting from a small amount of adsorbed moisture or other impurities; and the weight loss rate after modification is as high as 68.5 percent, which obviously should be derived from the poly cyclopentene coating layer on the surface of the MWCNTs. The results of fig. 5 confirm that: the MWCNTs with the specification are used as starting materials, and the surface of the MWCNTs can be subjected to crystallization coating modification by the polycyclopentene.
Example 5 and comparative example 5
1. Preparation of samples
(1) Example 5
Step 1: 150mg of MWCNTs (the source and specification are the same as those in example 4 above) and 750mg of hyperbranched polyethylene (HBPE, obtained by catalyzing ethylene coordination polymerization at 0.1MPa/35 ℃ by using a Pd-diimine catalyst 1) are added together into a cylindrical glass bottle with the size of 100mL (containing 75mL of analytically pure chloroform), ultrasonic dispersion is carried out at room temperature (power of 75W) for 0.5h, then glass wool (tightly filled in a glass tube with the diameter of 0.5cm and the height of 2cm) is filtered to remove large MWCNTs, the obtained filtrate is further subjected to vacuum filtration by using a polytetrafluoroethylene filter membrane with the diameter of 0.22 μm, leaching is carried out by using fresh chloroform (about 50mL), and the obtained filtered product is subjected to vacuum drying at room temperature for 8h to obtain MWCNTs (marked as MWCNTs-HBPE) with the surface modified by the HBPE.
Step 2: under the protection of nitrogen, 150mg (feeding concentration: 5mg/mL) of MWCNTs-HBPE obtained in the step 1 and 24mL of anhydrous dichloromethane are added into a Schlenk reaction bottle with the size of 50mL, and an initial dispersion of MWCNTs is obtained by ultrasonic treatment (power of 75W, time of 2h) at room temperature; 6mL of a monomer polymer cyclopentene (4.76g, charge concentration 4.67) was further added to the obtained dispersion10－4mol/mg MWCNTs) and 50mg Pd-diimine catalyst 3 (feed concentration 3.2X 10)-4mmol/mg MWCNTs), followed by a reaction continued for 8h at constant temperature (25 ℃) and magnetic stirring speed (200rpm) to obtain the reaction product.
And 3, step 3: and (3) centrifuging the reaction product obtained in the step 2 (9000rpm, 15min), removing the upper solution, collecting the lower product, performing ultrasonic washing by using fresh dichloromethane solvent (40mL), performing centrifugal separation again, repeating the washing step for 3 times, and performing vacuum drying on the obtained product at room temperature for 8 hours to obtain the final product.
(2) Comparative example 5
The same as in step 1 of example 5 above.
2. Characterization and testing
TEM analysis was performed with reference to example 1 and comparative example 1.
3. Result comparison and analysis
The foregoing examples 1-4 all start with MWCNTs that have not been surface modified. In this example 5, the surface of MWCNTs was modified with HBPE in advance, and by virtue of the non-covalent CH-pi action on the surfaces of the MWCNTs, part of the HBPE was non-covalently adsorbed on the surface of the MWCNTs, thereby obtaining MWCNTs with the surface modified with HBPE. TGA analysis confirmed that about 25 wt% of the HBPE was adsorbed on the surface of MWCNTs in the resulting MWCNTs-HBPE. The MWCNTs-HBPE is further used as a starting material, the surface of the MWCNTs-HBPE is subjected to polymer coating modification by the process, and the TEM result of the obtained composite material is shown in FIG. 6. Wherein FIG. 6(a) corresponds to comparative example 5 (i.e., starting material MWCNTs-HBPE), showing that the MWCNTs have a very low proportion of surface polymers; in contrast, as shown in FIG. 6(c-d), MWCNTs obtained after polymerization modification have a regular polymer-wrapped structure on the surface. The above results show that: the MWCNTs after surface modification are used as starting materials, and the process can also realize the crystallization coating of the polymer on the surface of the carbon nano tube.
Example 6 and comparative example 6
1. Preparation of samples
(1) Example 6
Step 1: 640mg of natural flake graphite (Sigma-Aldrich product, product No. 332461), 320mg of HBPE (the synthesis method is the same as in example 5) and 80mL of analytically pure chloroform were sequentially added into a 100mL cylindrical glass bottle, which was sealed and placed in an ultrasonic cell (power 250W) for ultrasonic treatment at room temperature for 48 hours. The resulting product was centrifuged at 4000rpm for 45min and approximately 70mL of the upper graphene solution (containing excess HBPE) was collected. And further carrying out vacuum filtration on the obtained graphene solution by using a polytetrafluoroethylene membrane (with the aperture of 0.22 mu m), leaching by using fresh chloroform to remove excessive HBPE, adding the obtained filtration product into 30mL of fresh chloroform, and carrying out ultrasonic treatment at room temperature for 8h to obtain the graphene solution with the excessive HBPE removed (the concentration of the graphene is 0.16mg/mL through UV-Vis).
Step 2: under the protection of nitrogen, adding 7mL of the graphene solution obtained in the step 1 (the mass of the graphene is 1.14mg, and the feeding concentration is 0.11mg/mL) into a 20mL glass test tube, and performing ultrasonic treatment (the power is 250W, and the time is 2h) at room temperature to obtain an initial graphene dispersion solution; further, 3mL of monomeric cyclopentene (2.04g, charge concentration of 0.03mol/mg graphene) and 45mg of Pd-diimine catalyst 1 (charge concentration of 0.05mmol/mg graphene) were added to the obtained dispersion, followed by continuous reaction for 1h at a constant temperature (25 ℃) by ultrasonic wave to obtain a polymerization product.
And 3, step 3: the reaction product obtained in the above step 2 was subjected to vacuum filtration using a polytetrafluoroethylene membrane (pore size 0.10 μm) as a filtration membrane and rinsed with fresh chloroform (about 80 mL). And adding the obtained filtration product into 10mL of fresh chloroform, and performing ultrasonic dispersion for 2h at room temperature to obtain a final graphene dispersion sample.
(2) Comparative example 6
The same as in step 1 of example 6 above.
2. Characterization and testing
Transmission Electron Microscope (TEM) analysis was carried out on a high-resolution transmission electron microscope (acceleration voltage 300kV) of the type Tecnai G2F30S-Twin, manufactured by Philips-FEI, the Netherlands. And (3) dropwise adding a small amount of graphene dispersion liquid onto the surface of a copper mesh (containing a porous carbon supporting film), and volatilizing the solvent for analysis.
3. Result comparison and analysis
Fig. 7 compares TEM results of graphene samples obtained in example 6 and comparative example 6. In which fig. 7(a) corresponds to comparative example 6, which is a sample of graphene (containing a small amount of HBPE, adsorbed to the surface of graphene by non-covalent interaction) that has not been modified by polymer coating, as shown in the figure, the graphene has a transverse dimension of about 1 μm, and is in an electron-transparent state, indicating that the thickness is thin and the surface is smooth, except for a small amount of regions where graphene fragments overlap the surface. Fig. 7(b) corresponds to example 6, which is obtained by polymerizing cyclopentene for 1h with Pd-diimine catalyst 1, and shows that there are distinct dark regions (shown as white circles) on the graphene surface belonging to the polymer crystal coating layer compared with comparative example 6. This shows that the process and the method can realize the crystallization coating of the polycyclopentene on the surface of the graphene.
Example 7 and comparative example 6
1. Preparation of samples
(1) Example 7
Step 1: the same procedure as in step 1 of example 6 was repeated.
Step 2: under the protection of nitrogen, adding 7mL of the graphene solution obtained in the step 1 (the mass of the graphene is 1.14mg, and the feeding concentration is 0.11mg/mL) into a 20mL glass test tube, and performing ultrasonic treatment (the power is 250W, and the time is 2h) at room temperature to obtain an initial graphene dispersion solution; further, 3mL of monomeric cyclopentene (2.04g, charge concentration of 0.03mol/mg graphene) and 45mg of Pd-diimine catalyst 1 (charge concentration of 0.05mmol/mg graphene) were added to the obtained dispersion, followed by continuous reaction for 2 hours at a constant temperature (25 ℃) by ultrasonic waves to obtain a polymerization product.
And 3, step 3: the same as in step 3 of example 6.
(2) Comparative example 6
The same as in step 1 of example 6 above.
2. Characterization and testing
The Transmission Electron Microscope (TEM) analysis was the same as in example 6 and comparative example 6.
3. Result comparison and analysis
Fig. 8 shows TEM results of graphene samples corresponding to example 7 and comparative example 6. FIG. 8(a) corresponds to comparative example 6, where the graphene was obtained from HBPE by ultrasonic exfoliation of natural graphite in chloroform as described above, and the graphene sheets in this sample are shown to be more transparent, indicating a smaller thickness, with lateral dimensions of about 0.5 to 1.0 μm, and in addition, more graphene fragments are present. FIG. 8(b) corresponds to example 7, which is obtained by polymerizing cyclopentene with catalyst 1 for 2h on the basis of the sample of comparative example 6; as shown in the figure, the obtained graphene sheets have a deeper contrast and a continuous polymer layer is present on the surface of the sheets compared to comparative example 6, and the white circles indicate clear outlines of the polymer layer on the surface of the graphene, which indicates that the polymer crystalline layer on the surface of the graphene becomes more continuous than in example 6 (see fig. 7(b)) due to the relatively long polymerization time. The above results thus confirm that the crystallization coating of the polycyclopentene on the surface of the graphene can be realized by the process.
Example 8 and comparative example 7
1. Preparation of samples
(1) Example 8
Step 1: the same procedure as in step 1 of example 6 was repeated.
Step 2: under the protection of nitrogen, adding 7mL of the graphene solution obtained in the step 1 (the mass of the graphene is 1.14mg, and the feeding concentration is 0.11mg/mL) into a 20mL glass test tube, and performing ultrasonic treatment (the power is 250W, and the time is 2h) at room temperature to obtain an initial graphene dispersion solution; further, 3mL of monomeric cyclopentene (2.04g, charge concentration of 0.03mol/mg graphene) and 45mg of Pd-diimine catalyst 1 (charge concentration of 0.05mmol/mg graphene) were added to the obtained dispersion, followed by continuous reaction for 3 hours at a constant temperature (25 ℃) by ultrasonic wave to obtain a polymerization product.
And 3, step 3: the same as in step 3 of example 6.
(2) Comparative example 7
Step 1: the same as in step 1 of example 6 above.
Step 2: under the protection of nitrogen, adding 7mL of the graphene solution obtained in the step 1 (the mass of the graphene is 1.14mg, and the feeding concentration is 0.11mg/mL) into a 20mL glass test tube, and performing ultrasonic treatment (the power is 250W, and the time is 2h) at room temperature to obtain an initial graphene dispersion solution; further, 45mg of Pd-diimine catalyst 1 (charge concentration of 0.05mmol/mg of graphene) was added to the obtained dispersion, followed by continuous reaction for 3 hours at a constant temperature (25 ℃) by ultrasonic wave to obtain a polymerization reaction product.
And 3, step 3: the same as in step 3 of example 6 above.
2. Characterization and testing
The Transmission Electron Microscope (TEM) analysis was the same as in example 6 and comparative example 6.
3. Result comparison and analysis
Fig. 9 shows TEM results of example 8 and comparative example 7. In embodiment 8, firstly, HBPE is used to prepare graphene in chloroform, and on this basis, a catalyst 1 is used to catalyze cyclopentene to polymerize for 3 hours to obtain a graphene composite sample; for comparison, in comparative example 7, the process parameters and steps were the same as in example 8, except that no polymerized monomer was introduced into the system. Fig. 9(a) corresponds to comparative example 7, and as shown in the figure, no obvious existence of a polymerization layer is seen on the surface of the obtained graphene, except that residues due to catalyst decomposition exist in local areas (see white circles); fig. 9(b) corresponds to example 8, and shows that after 3h of polymerization, the obtained graphene has a distinct polymer crystalline layer on the surface, the polymer layer has a rough surface, and a plurality of black spots are present at the same time, and the black spots are derived from Pd nanoparticles formed after the catalyst is decomposed. The above results show that: through the polymerization process, the Pd-diimine catalyst 1 can be used for catalyzing polymerization of cyclopentene, and crystallization coating of the polycyclopentene on the surface of graphene is achieved.
Claims (8)
1. A method for coating a carbon-based nano material surface by polymer induced crystallization comprises the following steps:
(1) adding carbon-based nano powder and an organic solvent into a reaction container, and obtaining a dispersion liquid by ultrasonic treatment at 5-35 ℃; further adding a polymerization monomer and an alpha-diimine palladium catalyst into the dispersion liquid, and then continuously reacting for a certain time under the action of stirring or an ultrasonic field at the temperature of 5-40 ℃ to obtain a reaction product; the organic solvent adopts one of the following analytically pure or chemically pure solvents: chlorobenzene, dichloromethane, trichloromethane; the polymerized monomer adopts alicyclic ringAn olefin; wherein the feeding concentration of the carbon-based nano powder is 0.001-100 mg/mL, and the feeding concentration of the polymeric monomer is 1.0 multiplied by 10-520mol/mg carbon-based nano powder, and the feeding concentration of the alpha-diimine palladium catalyst is 1.0 multiplied by 10-51.0mmol/mg carbon-based nanopowder;
(2) and (2) carrying out centrifugation or vacuum filtration on the reaction product obtained in the step (1) to remove redundant polymerized monomers and residues of the alpha-diimine palladium catalyst, and drying to obtain carbon-based nano powder coated with polymer crystals on the surface.
2. The method for coating the polymer on the surface of the carbon-based nano material according to claim 1, wherein in the step (1), the carbon-based nano powder is carbon nano tube powder with an unmodified surface or a chemically modified surface; or graphene with an unmodified surface or a chemically modified surface is adopted.
3. The method for coating a polymer on the surface of a carbon-based nanomaterial according to claim 2, wherein: the length of the carbon nano tube is controlled to be 0.1-500 mu m, the inner diameter is controlled to be 2-30 nm, the outer diameter is controlled to be 5-100 nm, the purity is controlled to be 50-100%, and the specific surface area is controlled to be 50-500 m2(ii)/g; the thickness of the graphene is controlled to be 1-10 layers, and the transverse dimension is controlled to be 0.1-100 mu m.
4. The method for coating the polymer on the surface of the carbon-based nano material according to any one of claims 1 to 3, wherein the polymerized monomer in the step (1) is one of the following monomers: cyclopropene, cyclobutene, cyclopentene, cyclohexene, cycloheptene.
5. The method for coating the polymer on the surface of the carbon-based nanomaterial according to any one of claims 1 to 3, wherein the alpha-diimine palladium catalyst in the step (1) is one of the following catalysts: an acetonitrile group Pd-diimine catalyst shown in a formula (1), a cyclic Pd-diimine catalyst containing a carbomethoxy group shown in a formula (2), and a cyclic Pd-diimine catalyst containing isobutyryl bromide shown in a formula (3):
wherein,
6. the method for coating the polymer on the surface of the carbon-based nano material according to claim 1, wherein in the step (1), the ultrasonic power is controlled to be 25-300W, and the ultrasonic time is controlled to be 0.5-8 h.
7. The method for coating the polymer on the surface of the carbon-based nano material according to claim 1, wherein in the step (1), the total time of the polymerization reaction is controlled to be 0.5-200 h.
8. The method for coating polymer on the surface of carbon-based nanomaterial according to claim 1, wherein the drying of the reaction product in the step (2) is performed by the following process: vacuum drying at room temperature to 80 ℃ for 0.5 to 48 hours.
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Cited By (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN106519737A (en) * | 2016-09-30 | 2017-03-22 | 宁波市鄞州烯泰新材料科技有限公司 | Preparation method of ultraviolet-curable graphene dispersion liquid |
| CN106586979A (en) * | 2016-11-01 | 2017-04-26 | 浙江工业大学 | Efficient preparation method of boron nitride nanosheet and organic dispersion liquid thereof |
| CN114478884A (en) * | 2022-03-24 | 2022-05-13 | 山东大学 | Method for preparing PAN-fullerene nano composite particles through aqueous suspension polymerization |
| CN117487439A (en) * | 2023-11-22 | 2024-02-02 | 安徽宇航派蒙健康科技股份有限公司 | Insulating heat-conducting material and preparation method thereof, insulating heat-conducting coating and preparation method thereof |
Citations (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN1829657A (en) * | 2003-08-05 | 2006-09-06 | 纳诺塞尔股份有限公司 | Polymer-based composites comprising carbon nanotubes as a filler, method for producing said composites, and associated uses |
| CN103447092A (en) * | 2013-09-13 | 2013-12-18 | 东华理工大学 | Graphene oxide supported Schiff base palladium catalyst as well as preparation method and application thereof |
-
2015
- 2015-03-09 CN CN201510101088.0A patent/CN104744728B/en active Active
Patent Citations (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN1829657A (en) * | 2003-08-05 | 2006-09-06 | 纳诺塞尔股份有限公司 | Polymer-based composites comprising carbon nanotubes as a filler, method for producing said composites, and associated uses |
| CN103447092A (en) * | 2013-09-13 | 2013-12-18 | 东华理工大学 | Graphene oxide supported Schiff base palladium catalyst as well as preparation method and application thereof |
Non-Patent Citations (2)
| Title |
|---|
| 徐飞霞等: "聚环戊烯包覆Fe3O4磁性纳米粒子的原位诱导结晶法制备及其结构表征", 《科技通报》 * |
| 贾瑛: "《轻质碳材料的应用》", 30 November 2013, 国防工业出版社 * |
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| CN106586979A (en) * | 2016-11-01 | 2017-04-26 | 浙江工业大学 | Efficient preparation method of boron nitride nanosheet and organic dispersion liquid thereof |
| CN106586979B (en) * | 2016-11-01 | 2019-12-24 | 浙江工业大学 | Boron nitride nanosheet and efficient preparation method of organic dispersion liquid thereof |
| CN114478884A (en) * | 2022-03-24 | 2022-05-13 | 山东大学 | Method for preparing PAN-fullerene nano composite particles through aqueous suspension polymerization |
| CN114478884B (en) * | 2022-03-24 | 2022-10-14 | 山东大学 | Method for preparing PAN-fullerene nano composite particles through aqueous suspension polymerization |
| CN117487439A (en) * | 2023-11-22 | 2024-02-02 | 安徽宇航派蒙健康科技股份有限公司 | Insulating heat-conducting material and preparation method thereof, insulating heat-conducting coating and preparation method thereof |
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