CN1234746C - Multi-carboxyl polymer grafted water-soluble carbon nanometer tube and preparation method thereof - Google Patents

Abstract

The invention provides a water-soluble carbon nanotube grafted with polycarboxy polymers generated in situ and a preparation method thereof. After the carbon nanotubes are treated, the surface has a specific initiator group; then the atom transfer radical polymerization is used to initiate the polymerization of the tert-butyl methacrylate monomer, and then the poly-tert-butyl methacrylate is hydrolyzed to make it The tert-butyl group is removed to form a carboxyl group, thereby becoming a water-soluble polymethacrylic acid, and obtaining a water-soluble carbon nanotube grafted with a polycarboxylate polymer. This preparation method is simple and easy to operate, with strong controllability; the obtained product shows good solubility in water, and can be used as a special additive for water-soluble polymer materials; at the same time, due to its nano-scale size, it can be used as a nano-device with special functions ; It can also be used as a carrier for material transfer and transfer between different systems; thus it has great application prospects in nanoscience, material science and biomedicine.

Description

More carboxyl polymer grafted water-soluble carbon nanometer tube and preparation method thereof

Technical field: the present invention relates to a kind of preparation method of water-soluble carbon nanometer tube, particularly more carboxyl polymer grafted water-soluble carbon nanometer tube and preparation method thereof.

Background technology: carbon nanotube (Cabon Nanotube is called for short CNT) is just found a kind of novel carbon structure in 1991, is the body that is rolled into by the Graphene lamella that carbon atom forms.Carbon nanotube be divided into Single Walled Carbon Nanotube (Single-wall Nanotube, SWNT) and multi-walled carbon nano-tubes (Multi-wall Nanotube, MWNT).Its preparation method mainly contains catalyse pyrolysis, arc-over, template and laser evaporation etc.

Because diameter is very little, length-to-diameter ratio is big, carbon nanotube is regarded as quasi-one-dimensional nanometer material.Confirmed now that carbon nanotube has peculiar electric property, superpower mechanical property, good adsorption property, thereby caused very big attention in the material field.The transistor and the indicating meter that have now had carbon nanotube to make come out.

Along with the development of nano science and technology, various carbon nanotubes with specified property cause people's interest gradually.The acid treatment that people such as Richard E.Smalley scrutinized carbon nanotube in 1998, obtained the products distribution situation under the different treatment condition, this has laid good basis (Science, 1998,280 (22): 1253-1255) for further studying later on.Afterwards, various modified carbon nano-tubes and composite structure thereof are produced out.Such as carbon nanotube with solvent solubility, have carbon nano tube device of molecular detection function or the like.

On the other hand, Sawamoto and Matyjaszewski have almost simultaneously found that independently transition metal-catalyzed " activity " controllable free-radical polymerisation of a kind of usefulness is atom transfer radical polymerization (ATRP).This method becomes the research focus of polymer chemistry in the world soon, and is described as " the recent studies on method of 21 century ".This method is to the control of target product with keep and be better than traditional polymerization greatly aspect the lower molecular weight distributing index, also avoided in the traditional method the harsh requirement to the polymerization environment.Simultaneously, because the popularity of initiator, especially, can in product, introduce functional group easily, also can synthesize multiple block polymer with the participation of the initiator of functional group.

Along with science and technology development, have the nanostructure of unique texture and function and the attention that nano-device has obtained people gradually, the annual report that a large amount of this respects are all arranged.Utilize the advantage of ATRP method, the combined carbon nanotube just can synthesize various carbon nano tube devices with ad hoc structure, and the application that this can expand above method and material greatly promotes the development of this science and technical field.

Summary of the invention: the objective of the invention is to utilize methods such as atom transfer radical polymerization by molecular designing, preparation more carboxyl polymer grafted water-soluble carbon nanometer tube satisfies the needs in different application field.

Technical scheme of the present invention is as follows:

By molecular designing, carbon nano tube surface is handled, make it to have the required active group of ATRP polyreaction, thereby can cause the polymerization that contains double bond monomer; At first in the presence of catalyzer and part, cause the tert-butyl methacrylate monomer polymerization, obtain the special butyl ester grafted of polymethyl acrylic acid carbon nanotube with atom transition free radical polymerization reaction; With the special butyl ester grafted of polymethyl acrylic acid carbon nanotube, then in the presence of catalyzer to processings that be hydrolyzed of the special butyl ester of polymethyl acrylic acid, make it to slough tertiary butyl, the generation carboxyl, thereby become water miscible polymethyl acrylic acid, then obtain more carboxyl polymer grafted water-soluble carbon nanometer tube.

The concrete preparation method of more carboxyl polymer grafted water-soluble carbon nanometer tube of the present invention is as follows:

Step (a): 1 weight part exsiccant carbon nanometer tube material and 0.1～100 weight part acid with strong oxidizing property, with 40～100kHz ultrasonication, 0.1～100hr post-heating to 20～200 ℃, reaction 0.5～100hr, use the filter membrane suction filtration, repetitive scrubbing repeatedly to neutral, obtains the acidifying carbon nanotube behind 0～180 ℃ of vacuum-drying 10～30hr;

Step (b): add step (a) gained acidifying carbon nanotube 1 weight part and acylating agent 1～100 weight part, behind 40～100kHz ultrasonication, 10～1000min, be heated to 20～200 ℃, reaction 0.5～100hr down stirs and refluxes, suction filtration and repetitive scrubbing are removed acylating agent, obtain acylated carbon nano-tube;

Step (c): add step (b) gained acidylate carbon nanotube 1 weight part and polyvalent alcohol or polyamine 1～50 weight part, sealing, take out inflated with nitrogen repeatedly three times, behind 40～100kHz ultrasonication, 10～1000min, react 1～20hr down at 20～200 ℃, suction filtration is behind the repetitive scrubbing, 0～180 ℃ of vacuum-drying obtains the carbon nanotube that the surface has hydroxyl or amido;

Step (d): add carbon nanotube 1 weight part and alpha-halogen carboxylic acid halides 1～50 weight part that step (c) gained surface has hydroxyl or amido, sealing, take out inflated with nitrogen repeatedly three times, behind 40～100kHz ultrasonication, 10～1000min, react 1～20hr down at 20～200 ℃, suction filtration is after the washing, 0～180 ℃ of vacuum-drying obtains the carbon nanotube that the surface has initiating group;

Step (e): add 0.01～1 weight part catalyzer, 0.01～5 weight part part, the surface that adds step (d) gained again has carbon nanotube 1 weight part of initiating group, and solvent 0～50 weight part fills Ar or N after the sealing ₂1～100min, add tert-butyl methacrylate monomer 0.01～80 weight part, continue inflated with nitrogen or argon gas 1～100min, react 0.01～1000hr down at 0～150 ℃, after viscosity is significantly increased, stopped reaction precipitates in poor solvent, and the gained precipitation heavily is dissolved in good solvent, suction filtration, washing, 0～180 ℃ of vacuum-drying obtains the special butyl ester grafted of polymethyl acrylic acid carbon nanotube;

Step (f): add the special butyl ester grafted of step (e) gained polymethyl acrylic acid carbon nanotube 1 weight part, solvent 0.01～100 weight part, catalyzer 0.01～100 weight part, airtight back is reacted 0.01～1000hr down at 0～100 ℃, solvent and catalyzer are removed, obtained more carboxyl polymer grafted water-soluble carbon nanometer tube.

Used carbon nanotube is the single wall or the multi-walled carbon nano-tubes of catalyse pyrolysis, arc-over, template and the preparation of laser evaporation method in the inventive method step (a).

The used acid with strong oxidizing property of the inventive method step (a) comprises 0.1～70% weight acid concentration nitric acid, 0.1～100% weight acid concentration sulfuric acid, 1/100～100/1 mol ratio nitric acid and sulfuric acid mixed solution, 1/100～100/1 mol ratio potassium permanganate and sulfuric acid mixed solution, 1/100～100/1 mol ratio potassium permanganate and hydrochloric acid mixed solution, 1/100～100/1 mol ratio potassium permanganate and nitric acid mixing solutions, 1/100～100/1 mol ratio H ₂O ₂With sulfuric acid mixed solution, 1/100～100/1 mol ratio H ₂O ₂With hydrochloric acid mixed solution, 1/100～100/1 mol ratio H ₂O ₂With the nitric acid mixing solutions.

Used acylating agent comprises phosphorus trichloride, phosphorus pentachloride, thionyl chloride, phosphorus tribromide, phosphorus pentabromide, thionyl bromide in the inventive method step (b).

Polyvalent alcohol or polyamine material used in the inventive method step (c) comprise ethylene glycol, quadrol, glycerol, third triamine, 1, the 2-propylene glycol, 1,2-propylene diamine, 1, ammediol, 1,3-propylene diamine, 1,4-butyleneglycol, 1,4-butanediamine, 1,2-butyleneglycol, 1,2-butanediamine, 1,3 butylene glycol, 1,3-butanediamine, trihydroxybutane, fourth triamine, polyoxyethylene glycol, polyethyene diamine.

Used alpha-halogen carboxylic acid halides comprises alpha-brominated butyryl bromide, alpha-brominated isobutyl acylbromide, alpha-brominated propionyl bromide, alpha-chloro butyryl chloride, alpha-chloro isobutyryl chloride, alpha-chloro propionyl chloride in the inventive method step (d).

Do not use solvent among the inventive method step (c), (d) or with dimethyl sulfoxide (DMSO), N, dinethylformamide, N,N-dimethylacetamide, N-N-methyl-2-2-pyrrolidone N-, chloroform, tetrahydrofuran (THF), ethyl acetate, acetone, acetonitrile, butanone, triethylamine, pyridine, dimethylamino pyridine are that solvent or the mixed solvent that contains these solvents are reaction medium.

Catalyst system therefor is the metallic compound that contains Cu (I), Fe (II), Mo (V), Re (V), Ru (II), Ni (I), Pb (II) such as cuprous chloride, cuprous bromide, iron protochloride, ferrous bromide, lithium molybdate, ReO in the inventive method step (e) ₂I (PPh ₃) ₂, RuCl ₂, Ni (NCN) Br, Pd (OAc) ₂Used part is 2-dipyridyl, Tetramethyl Ethylene Diamine, pentamethyl--diethyl triamine, hexamethyl-triethyl tetramine, oxalic acid, propanedioic acid, Succinic Acid, phthalic acid, triphenylphosphine, tri-n-butyl phosphine; Solvent for use is dimethyl sulfoxide (DMSO), N, dinethylformamide, N,N-dimethylacetamide, N-N-methyl-2-2-pyrrolidone N-, chloroform, methylene dichloride, ethylene dichloride, tetrahydrofuran (THF), ethyl acetate, acetone, butanone, acetonitrile, propyl alcohol, ethanol, methyl alcohol or contain the mixture of these solvents.

Be that solvent or the mixed solvent that contains these solvents are reaction medium with water, methyl alcohol, ethanol, methylene dichloride, trichloromethane, tetracol phenixin, tetrahydrofuran (THF), ethyl acetate, acetone, acetonitrile, butanone, triethylamine, pyridine, dimethylamino pyridine in the inventive method step (f); With hydrochloric acid, sulfuric acid, phosphoric acid, nitric acid, trifluoroacetic acid and composition thereof as catalyzer.

Preparation method provided by the invention is simple, and controllability is strong; Gained more carboxyl polymer grafted water-soluble carbon nanometer tube shows good solubility owing to have a large amount of wetting ability carboxylic groups in water; This solvability has been improved the workability of carbon nanotube greatly, can be used as the specialist additive of water-soluble high-molecular material; Owing to its nano level size, can be used as the nano-device of specific function simultaneously, construct specific quantum structure; Also can be used as the carrier of material transfer and transfer between different system, realize specific purpose; Thereby have purposes widely at nano science, Materials science and biomedical aspects, wide application prospect is arranged.

Description of drawings:

Fig. 1: more carboxyl polymer grafted water-soluble carbon nanometer tube ¹H NMR spectrogram

Fig. 2: more carboxyl polymer grafted water-soluble carbon nanometer tube infrared spectrum

Fig. 3: the solvability photo of more carboxyl polymer grafted water-soluble carbon nanometer tube in water and chloroform

Embodiment: the following examples are to further specify of the present invention, rather than limit the scope of the invention.

Embodiment 1: the multi-walled carbon nano-tubes with the catalytic pyrolysis method preparation is an initial raw material; acidified; after the acidylate, connect ethylene glycol, again with alpha-brominated isobutyryl bromine reaction; with the special butyl ester PtBA of ATRP method grafted polyacrylic acid); then in the presence of catalyzer to processings that be hydrolyzed of the special butyl ester of polyacrylic acid, make it to slough tertiary butyl, the generation carboxyl; thereby become water miscible polyacrylic acid, then obtain more carboxyl polymer grafted water-soluble carbon nanometer tube.

Step (a): in the single neck round-bottomed flask of the 100mL that the magnetic agitation rotor is housed, add 2g exsiccant carbon nanometer tube material and 20mL 60% weight ratio concentration concentrated nitric acid, with 40kHz ultrasonication 30min post-heating to 120 ℃, reaction 24hr down stirs and refluxes, with φ 0.22 μ m tetrafluoroethylene millipore filtration suction filtration, repeatedly to neutral, obtain acidifying carbon nanotube behind 80 ℃ of vacuum-drying 24hr with the deionized water repetitive scrubbing;

Step (b): in the single neck round-bottomed flask of the 100mL that the magnetic agitation rotor is housed, add step (a) gained acidifying carbon nanotube 1.5g and thionyl chloride 8g, behind 40kHz ultrasonication 30min, be heated to 60 ℃, reaction 24hr down stirs and refluxes, suction filtration and repetitive scrubbing are removed thionyl chloride, obtain acylated carbon nano-tube;

Step (c): in the single neck round-bottomed flask of the 100mL that the magnetic agitation rotor is housed, add step (b) gained acidylate carbon nanotube 1.3g and ethylene glycol 25g, seal with the turned welt soft rubber ball, take out inflated with nitrogen repeatedly three times, behind 40kHz ultrasonication 30min, react 24hr down at 100 ℃, suction filtration is removed unreacted reactant and byproduct of reaction, with behind the deionized water wash, 80 ℃ of vacuum-dryings obtain the carbon nanotube that the surface has hydroxyl repeatedly;

Step (d): in the single neck round-bottomed flask of the 100mL that the magnetic agitation rotor is housed, adding step (c) gained surface has the carbon nanotube 1.1g and the alpha-brominated isobutyl acylbromide 1g of hydroxyl, seal with the turned welt soft rubber ball, take out inflated with nitrogen repeatedly three times, behind 40kHz ultrasonication 30min, at 20 times reaction 1～20hr, suction filtration is removed unreacted reactant and byproduct of reaction, with behind the deionized water wash, 80 ℃ of vacuum-dryings obtain the carbon nanotube that the surface has initiating group repeatedly;

Step (e): in the single neck round-bottomed flask of the 50mL that the magnetic agitation rotor is housed, add 0.6g CuBr, 0.7g part PMDETA (pentamethyl--diethyl triamine), the surface that adds step (d) gained again has the carbon nanotube 1g of initiating group, and solvent DMF 10mL fills N after the sealing ₂10min adds the special butyl ester monomer of vinylformic acid 10mL, continues to fill N ₂10min reacts 20hr down at 100 ℃, after viscosity is significantly increased, and stopped reaction, after the chloroform dilution, suction filtration, unreacted monomer and catalyzer etc. are removed in washing, and 80 ℃ of vacuum-dryings obtain the special butyl ester grafted of polyacrylic acid carbon nanotube, obtain material 2.8g;

Step (f): add the special butyl ester grafted of step (e) gained polyacrylic acid carbon nanotube 1g, methylene dichloride 10mL, CF ₃COOH 0.5g, airtight after stirring reaction 24hr at room temperature, wait the generation post precipitation, solvent and catalyzer are removed, obtain more carboxyl polymer grafted water-soluble carbon nanometer tube 0.7g.

Fig. 1 has provided product more carboxyl polymer grafted water-soluble carbon nanometer tube ¹H NMR spectrogram, main polymer chain (CH ₂-: δ=2.7～2.9ppm;-CH-: δ=2.0～2.3ppm) and reactive hydrogen (proof of COOH: δ=9.1～9.4ppm) polyacrylic structure.The infrared spectrum of product (Fig. 2) has clearly proved carbonyl (～1730cm ^-1) and reactive hydrogen (3200～3700cm ^-1).Fig. 3 has provided the solvability photo of product more carboxyl polymer grafted water-soluble carbon nanometer tube in water and chloroform, can find out intuitively that from figure product can well dissolve in water and disperse, and can not dissolve in organic solvent.

Claims (10)

1. the preparation method of the water-soluble carbon nanotube of polycarboxyl polymer grafting, it is characterized in that concrete preparation method is as follows: Step (a): 1 weight part of dry carbon nanotube raw material and 0.1 to 100 weight parts of strong oxidizing acid, ultrasonic treatment at 40 to 100 kHz for 0.1 to 100 hours, heating to 20 to 200 ° C, reaction for 0.5 to 100 hours, and filtering Suction filtration, repeated washing several times until neutral, vacuum drying at 0-180°C for 10-30 hours to obtain acidified carbon nanotubes; Step (b): adding 1 part by weight of the acidified carbon nanotubes obtained in step (a) and 1-100 parts by weight of an acylating agent, ultrasonic treatment at 40-100 kHz for 10-1000 min, heating to 20-200 ° C, stirring and reflux React for 0.5-100 hours, filter with suction and wash repeatedly to remove the acylating agent, and obtain acylated carbon nanotubes; Step (c): adding 1 part by weight of the acylated carbon nanotubes obtained in step (b) and 1 to 50 parts by weight of polyol or polyamine, sealing, repeatedly pumping and filling nitrogen three times, and after ultrasonic treatment at 40 to 100 kHz for 10 to 1000 minutes, React at 20-200°C for 1-20 hours, filter with suction, wash repeatedly, and dry in vacuum at 0-180°C to obtain carbon nanotubes with hydroxyl or amine groups on the surface; Step (d): adding 1 weight part of carbon nanotubes with hydroxyl or amino groups on the surface obtained in step (c) and 1 to 50 weight parts of α-halogenated acyl halides, sealing, and repeatedly pumping nitrogen gas three times, at 40 to 100 kHz After ultrasonic treatment for 10 to 1000 minutes, react at 20 to 200°C for 1 to 20 hours, suction filter, wash, and vacuum dry at 0 to 180°C to obtain carbon nanotubes with initiator groups on the surface; Step (e): adding 0.01 to 1 weight part of catalyst, 0.01 to 5 weight parts of ligand, and then adding 1 weight part of carbon nanotubes with initiating groups on the surface obtained in step (d), and 0 to 50 weight parts of solvent, After sealing, fill with Ar or N ₂ for 1 to 100 minutes, add 0.01 to 80 parts by weight of tert-butyl methacrylate monomer, continue to fill with nitrogen or argon for 1 to 100 minutes, and react at 0 to 150 ° C for 0.01 to 1000 hours, and the viscosity is obvious After the increase, stop the reaction, precipitate in a poor solvent, redissolve the obtained precipitate in a good solvent, suction filter, wash, and vacuum dry at 0-180°C to obtain carbon nanotubes grafted with poly-tert-butyl methacrylate; Step (f): Add 1 part by weight of carbon nanotubes grafted with poly-tert-butyl methacrylate obtained in step (e), 0.01 to 100 parts by weight of solvent, and 0.01 to 100 parts by weight of catalyst; After reacting for 0.01-1000 hours, the solvent and the catalyst are removed to obtain water-soluble carbon nanotubes grafted by polycarboxylate polymers. 2. the preparation method of the water-soluble carbon nanotube of polycarboxylate polymer grafting according to claim 1 is characterized in that the carbon nanotube used in the step (a) is selected from catalytic pyrolysis, arc discharge, template method or Single-walled or multi-walled carbon nanotubes prepared by laser evaporation method. 1 3. the preparation method of the water-soluble carbon nanotube of polycarboxy polymer grafting according to claim 1 is characterized in that the used strong oxidative acid of step (a) is selected from nitric acid, sulfuric acid, nitric acid and sulfuric acid mixed acid, adds Hydrochloric acid, nitric acid, sulfuric acid or their mixed acids with potassium permanganate _{or H2O2} . 4. The preparation method of the water-soluble carbon nanotubes grafted by polycarboxy polymers according to claim 1 is characterized in that the acylating agent used in the step (b) is selected from phosphorus trichloride, phosphorus pentachloride, Sulfuryl chloride, phosphorus tribromide, phosphorus pentabromide or thionyl bromide. 5. the preparation method of the water-soluble carbon nanotube of polycarboxyl polymer grafting according to claim 1 is characterized in that used polyalcohol or polyamine material are selected from ethylene glycol, ethylenediamine in step (c) , glycerol, glycerine triamine, 1,2-propanediol, 1,2-propanediamine, 1,3-propanediol, 1,3-propanediamine, 1,4-butanediol, 1,4-butane Diamine, 1,2-butanediol, 1,2-butanediamine, 1,3-butanediol, 1,3-butanediamine, butanetriol, butanetriamine, polyethylene glycol or polyethylene diamine. 6. The preparation method of the water-soluble carbon nanotubes grafted by polycarboxy polymers according to claim 1 is characterized in that the α-haloacyl halide used in the step (d) is selected from α-bromobutyryl bromide, α-bromoisobutyryl bromide, α-bromopropionyl bromide, α-chlorobutyryl chloride, α-chloroisobutyryl chloride or α-chloropropionyl chloride. 7. the preparation method of the water-soluble carbon nanotube of polycarboxyl polymer grafting according to claim 1 is characterized in that step (c), (d) do not use solvent or use dimethyl sulfoxide, N, N-dimethylformamide, N,N-dimethylacetamide, N-methyl-2-pyrrolidone, chloroform, tetrahydrofuran, ethyl acetate, acetone, acetonitrile, butanone, triethylamine, pyridine, dimethyl One of the aminopyridines is used as a solvent or a mixed solvent containing these solvents is used as a reaction medium. 8. the preparation method of the water-soluble carbon nanotube of polycarboxy polymer grafting according to claim 1 is characterized in that used catalyst is selected from cuprous chloride, cuprous bromide, protochloride in step (e) Iron, ferrous bromide, lithium molybdate, ReO ₂ I(PPh ₃ ) ₂ , RuCl ₂ , Ni(NCN)Br or Pd(OAc) ₂ ; Amines, pentamethyl-diethyltriamine, hexamethyl-triethylenetetramine, oxalic acid, malonic acid, succinic acid, phthalic acid, triphenylphosphine or tri-n-butylphosphine; Solvent used is selected from dimethylsulfoxide, N,N-dimethylformamide, N,N-dimethylacetamide, N-methyl-2-pyrrolidone, chloroform, dichloromethane, dichloroethane, Tetrahydrofuran, ethyl acetate, acetone, methyl ethyl ketone, acetonitrile, propanol, ethanol or methanol or mixtures containing these solvents. 9. the preparation method of the water-soluble carbon nanotube of polycarboxyl polymer grafting according to claim 1 is characterized in that in step (f) with water, methyl alcohol, ethanol, methylene dichloride, chloroform, tetrachloromethane Carbon dioxide, tetrahydrofuran, ethyl acetate, acetone, acetonitrile, butanone, triethylamine, pyridine or dimethylaminopyridine as a solvent or a mixed solvent containing these solvents as a reaction medium; hydrochloric acid, sulfuric acid, phosphoric acid , nitric acid or trifluoroacetic acid or a mixture thereof as a catalyst. 10. The water-soluble carbon nanotubes grafted with polycarboxy polymers, characterized in that the water-soluble carbon nanotubes grafted with polycarboxy polymers are obtained by the preparation method according to any one of claims 1-9.

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