CN104592933B

CN104592933B - A kind of nano combined absorbing material

Info

Publication number: CN104592933B
Application number: CN201510016139.XA
Authority: CN
Inventors: 冯丹
Original assignee: Individual
Current assignee: Yu Qiangbo
Priority date: 2015-01-12
Filing date: 2015-01-12
Publication date: 2018-04-06
Anticipated expiration: 2035-01-12
Also published as: CN104592933A

Abstract

The invention discloses a kind of nano combined absorbing material.For this method with the preparation including graphite oxide, hollow four ferric oxide nanometer particle is successfully loaded to graphene film layer surface by the step such as scattered.The method of the present invention is convenient, can prepare the excellent graphene of absorbing property/hollow ferroso-ferric oxide/polyaniline nano-composite material.

Description

A kind of nano combined absorbing material

Technical field

The present invention relates to absorbing material field, more particularly to a kind of nano combined absorbing material.

Background technology

With the development of science and technology and electronics industry, increasing electromagenetic wave radiation is present in around us, passes through Cross research to show, excessive electromagenetic wave radiation, which removes, can cause nervous system, immune system, reproductive system and blood circulation system etc. to be sent out Outside raw obstacle, in some instances it may even be possible to induce the serious disease including all kinds of cancers.It is chronically in electromagnetic wave environment, quilt in human body Electromagnetic wave damage and have not enough time to the tissue and organ of self-regeneration damage can turn into because of long term accumulation dynamic disease become, Can threat to life when serious.

Graphene, due to its unique single layer structure, to make it have ultralight density, big specific surface area, electric conductivity excellent The features such as good and high dielectric constant, become a kind of novel wave-absorbing material.In addition, oxidized graphenic surface is largely sudden and violent The chemical bond of dew is more prone to the dielectric relaxor of outer-shell electron and electromagnetic wave of decaying in the presence of electromagnetic field, exists for graphene The applications expanding in ripple field prospect is inhaled, not only can be with the hollow ferriferrous oxide nano-particle of graphenic surface carried magnetic Magnetism of material energy is improved, strengthens the magnetic loss of composite, is advantageous to the impedance matching of composite, and ferroso-ferric oxide It is in three-dimensional graphite structure that grain reduces graphene and stacked again in the drying process as spacer medium, to stablizing graphene sheet layer knot Structure plays considerable effect.

The technical problems to be solved by the invention are in view of the shortcomings of the prior art, there is provided a kind of nano combined suction ripple material Material.

Technical scheme is as follows：

A kind of nano combined absorbing material, it is characterised in that the absorbing material is laminar nano composite wave-suction material, hollow The ferroferric oxide nano granules homoepitaxial of semiglobe is on two surfaces up and down of redox graphene piece, and the one of formation The absorbing material of the multi-layer compound structure of kind nano thickness, it is about hollow the four of 20-50nm to load particle diameter on graphene sheet layer Fe 3 O particle, and polyaniline-coated is in the graphene film layer surface for being loaded with hollow Nano ferroso-ferric oxide, the suction ripple material The preparation method of material comprises the following steps：

Step 1, size is made in graphite and obtains graphite powder for 50-200 mesh, added afterwards to the salt that mass fraction is 35% In acid solution, 30min is stirred, uses deionized water to rinse repeatedly afterwards so that pH value is neutrality, drying is stand-by；

By the graphite powder above dried, potassium peroxydisulfate and P₂O₅Add in the concentrated sulfuric acid, form mixture, the mixing formed The pH value of thing is 1.5, and the mixture is stirred into 1-2h at 60 DEG C, is then warming up at 80 DEG C and stirred with 5 DEG C/min speed 2-4h, 87 DEG C of stirring 1-2h are finally warming up to 2 DEG C/min, then using the distilled water diluting mixture, by the mixture PH value is diluted to 3.6, uses distillation water filtration after placing 36h so that mixture pH value is 6-7, carries out drying at room temperature afterwards, described Graphite powder, potassium peroxydisulfate, P₂O₅Mass ratio with the concentrated sulfuric acid is 1-3:1-2:1-2:5-10；

Dried mixture is added in concentrated nitric acid and stirs 45-60min so that pH value 2-4, it is described dried The mass ratio of mixture and concentrated nitric acid is 1-4:50-100, KMnO is added for the first time at -8 DEG C after stirring₄, stirring 30min, second is cooled at -12 DEG C afterwards and adds KMnO₄, 30min is stirred, is finally cooled at -15 DEG C and adds for the third time KMnO₄, 20min, the graphite mixture pre-oxidized are stirred, the first time adds KMnO₄, second of addition KMnO₄With KMnO is added three times₄Mass ratio be 1:2:3, the dried mixture and total KMnO₄Ratio be 1-2:10-15；

After the graphite mixture pre-oxidized is filtered and dried, it is positioned in Muffle furnace and is heated, at heat The temperature of reason handles 15-20s, handles 20-30s at 1180 DEG C, expanded to handle 10-20s at 1100 DEG C at 1150 DEG C Graphite；

Step 2, the made expanded graphite of step 1 is put into incubator and is warming up to 40 DEG C, react 3h, then, added With consistent amount of first distilled water of graphite mixture volume of pre-oxidation, 2.5h is then reacted, by incubator temperature to 40 DEG C, after-fractionating water and H are added again₂O₂10-60min is reacted, the amount of the after-fractionating water is the 1-1.5 of the first distilled water Times, after-fractionating water and H₂O₂Volume ratio be 4-20:1, react and 10min is centrifuged after terminating, rotating speed 8000~ 10000r/min, product is washed with hydrochloric acid solution after centrifugation, and the volume of the hydrochloric acid solution is bulk product after centrifugation 10-50 times, finally dialyse and obtain graphite oxide in 7-8 days；N- hydroxyls are added after graphite oxide is used into dimethyl sulfoxide ultrasonic dissolution Base succimide and self-control surface conditioning agent stir 2h at 35 DEG C, and product is filtered, washed, dried, that is, obtains surface The graphite oxide of processing.

Step 3, surface grafting, the graphite oxide being surface-treated obtained by step 3 and the polymer of required grafting are mixed Close, and be heated to 80-95 DEG C and be passed through nitrogen, and add the solution containing tetravalence cerium ion, stirring reaction 2-4h, filtered, Washing, dry, obtain the polymer grafting graphite oxide, the mass ratio of the graphite oxide and the polymer of required grafting is 1-2：1-3, the polymer of required grafting is by methyl methacrylate, GMA, dimethylaminoethyl acrylate methyl Amino ethyl ester and diethylaminoethyl methacrylate composition, the methyl methacrylate, GMA, The mass ratio of dimethylaminoethyl methacrylate and diethylaminoethyl methacrylate is 1:1:2:1；

Step 4, after the graphite 1-2g of the surface grafting obtained by step 2 is freezed dried at -30 DEG C with 1- 10g PEO-PPOX-PEO triblock copolymers are put into ultrasound point in 500ml ethylene glycol in the lump Dissipate and form uniform first dispersion liquid；Simultaneously by 4-15g by Fecl₃·6H₂O、Fecl₂·4H₂O and acetyl acetone iron composition Mixture, 6~25g polyvinylpyrrolidones and 10~50g NH₄Ac, which is dissolved in 500-1000mL ethylene glycol, forms Two dispersion liquids, the first dispersion liquid and the second dispersion liquid are mixed, and adjusted with ammoniacal liquor, it is the clear of 8-10 to make pH value Clear solution, the Fecl₃·6H₂O、Fecl₂·4H₂The mass ratio of O and acetyl acetone iron is 1:1:0.5；

Step 5, the settled solution obtained by 100ml step 3 is put into reactor, after sealing, is heated to 150 DEG C, 2h is incubated, is warming up to 200 DEG C afterwards with 2-4 DEG C/min heating rate, is incubated 4h, afterwards with 3-6 DEG C/min heating speed Rate is warming up to 235 DEG C, is incubated 3h, then 200 DEG C of insulation 2h is cooled to 5-7 DEG C/min cooling rate, finally again with 3-6 DEG C/min heating rate is warming up to 235 DEG C, is incubated 7h, after the completion of question response, reactor is taken out, is allowed to be cooled to room temperature, The cooling rate is 3-6 DEG C/min, and the black powder of gained is centrifuged into 10min, 8000~10000r/min of rotating speed, adopted With absolute ethyl alcohol and deionized water, respectively washing three times, is dried in vacuo 24h at 50~70 DEG C, obtains the first product；

The products of 5g first and 5-10g aniline monomers are added into the solution of DBSA, ultrasonic disperse 65min, the second product is formed, the mass ratio of first product and DBSA is 1-1.5:8-15；

3g ammonium persulfates are dissolved in 80-120ml distilled water, are slowly dropped in the second product, stirring reaction 15h, After reaction terminates, filter, colourless to filtrate with distilled water, ethanol washed product respectively, 50~70 DEG C of 24~36h of vacuum drying, Obtain nano combined absorbing material.

Graphite oxide g described in step 2, dimethyl sulfoxide ml, N- hydroxysuccinimide g and self-control surface conditioning agent g Ratio be 0.2-0.5：20-25：2-5：0.1-05, the self-control surface conditioning agent is by dicyclohexylcarbodiimide, dodecane Base sodium sulfonate, kayexalate and polyacrylic acid composition, the dicyclohexylcarbodiimide, dodecyl sodium sulfate, gather The mass ratio of SSS and polyacrylic acid is 1:1:2:3.

The concentration of hydrochloric acid is volume ratio 1 in the described step 2:10 hydrochloric acid solution.

When graphite coupling part weak in graphite after ball milling is broken up, it is not necessary to by ultrasonic disperse, preparing Acted in journey by colding and heat succeed each other with small molecule, both atom can be peeled off, and reduce energy consumption, and production cycle so that be raw Produce cycle time 5-15h.

The preparation method of the absorbing material of the present invention passes through growth in situ of the ferroso-ferric oxide on graphene sheet layer and poly- Aniline graphene/ferriferrous oxide composite material surface in-situ polymerization, so as to realize the excellent wave-absorbing effect of material, anti- The Absorber Bandwidth penetrated below loss -10dB is 4.8-5.1GHz；

Heated up when applicant prepares pre-oxidation graphite by numerous studies step 1 of the present invention using different heating rates To required whipping temp, the stirring under different whipping temps stage by stage, and add at different temperature stage by stage Enter KMnO₄Contribute to the preparation of pre-oxidation graphite so that oxidation is more thoroughly higher than common disposable stirring and addition KMnO₄ 10-15%, and be advantageous to the formation of later stage graphene；

Further surface treatment is done for graphite oxide in step 2, using homemade surface conditioning agent, by adding After adding can enough make up graphite oxide surface for metal iron ion affinity it is low the shortcomings that, increase surface Fe ions load Amount, also cause simultaneously Fe ions below graphite surface it is scattered more uniformly, the specific surface area of its graphite reaches 35- 37m²/g；

Graphite by grafting processing just has fabulous dissolubility in the later stage, more easily added to high molecular polymer base In body, the associativity of the nano composite material formed is more prominent.

During being warming up to required temperature using different heating rates in step 5 of the present invention, by once dropping Temperature insulation, more contributes to the formation of graphene/hollow ferroso-ferric oxide so that the absorbing property of the absorbing material ultimately formed It is stronger, it is better than the performance 5-15% of the absorbing material of commonsense method formation, and the tri compound absorbing material performance formed It is more stable；

The present invention protects in preparation process without using nitrogen or oxygen, without hot conditions, can effectively drop Low synthesis cost, and dispersing uniformity of the nano particle in graphite is effectively raised, improve the performance of product.

Embodiment

Below in conjunction with specific embodiment, the present invention is described in detail.

Step 4, after the graphite 1-2g of the surface grafting obtained by step 2 is freezed dried at 30 DEG C with 1- 10g PEO-PPOX-PEO triblock copolymers are put into ultrasound point in 500ml ethylene glycol in the lump Dissipate and form uniform first dispersion liquid；Simultaneously by 4-15g by Fecl₃·6H₂O、Fecl₂·4H₂O and acetyl acetone iron composition Mixture, 6~25g polyvinylpyrrolidones and 10~50g NH₄Ac, which is dissolved in 500-1000mL ethylene glycol, forms Two dispersion liquids, the first dispersion liquid and the second dispersion liquid are mixed, and adjusted with ammoniacal liquor, it is the clear of 8-10 to make pH value Clear solution, the Fecl₃·6H₂O、Fecl₂·4H₂The mass ratio of O and acetyl acetone iron is 1:1:0.5；

The absorbing material is laminar nano composite wave-suction material, and the ferroferric oxide nano granules of hollow hemisphere structure are uniform It is grown in two surfaces up and down of redox graphene piece, a kind of suction ripple material of the multi-layer compound structure of nano thickness of formation Material, the hollow ferriferrous oxide particles that particle diameter is about 20-50nm are loaded on graphene sheet layer, and polyaniline-coated is in being loaded with The graphene film layer surface of hollow Nano ferroso-ferric oxide.

It should be appreciated that for those of ordinary skills, can according to the above description be improved or converted, And all these modifications and variations should all belong to the protection domain of appended claims of the present invention.

Claims

A kind of 1. nano combined absorbing material, it is characterised in that the absorbing material is laminar nano composite wave-suction material, hollow half The ferroferric oxide nano granules homoepitaxial of spherical structure is in two surfaces up and down of redox graphene piece, one kind of formation The absorbing material of the multi-layer compound structure of nano thickness, hollow four oxidation that particle diameter is 20-50nm is loaded on graphene sheet layer Three iron particles, and polyaniline-coated is in the graphene film layer surface for being loaded with hollow Nano ferroso-ferric oxide, the absorbing material Preparation method comprises the following steps：

Step 1, size is made in graphite and obtains graphite powder for 50-200 mesh, added afterwards molten to the hydrochloric acid that mass fraction is 35% In liquid, 30min is stirred, uses deionized water to rinse repeatedly afterwards so that pH value is neutrality, drying is stand-by；

By the graphite powder above dried, potassium peroxydisulfate and P₂O₅Add in the concentrated sulfuric acid, form mixture, the mixture formed PH value is 1.5, and the mixture is stirred into 1-2h at 60 DEG C, is then warming up to 5 DEG C/min speed at 80 DEG C and stirs 2-4h, Finally 87 DEG C are warming up to 2 DEG C/min stir 1-2h, it is then using the distilled water diluting mixture, the pH value of the mixture is dilute Release to 3.6, use distillation water filtration after placing 36h so that mixture ph 6-7, carry out drying at room temperature, the graphite afterwards Powder, potassium peroxydisulfate, P₂O₅Mass ratio with the concentrated sulfuric acid is 1-3:1-2:1-2:5-10；

Dried mixture is added in concentrated nitric acid and stirs 45-60min so that pH value 2-4, the dried mixing The mass ratio of thing and concentrated nitric acid is 1-4:50-100, KMnO is added for the first time at -8 DEG C after stirring₄, 30min is stirred, it After be cooled at -12 DEG C second and add KMnO₄, 30min is stirred, is finally cooled at -15 DEG C and adds KMnO for the third time₄, stirring 20min, the graphite mixture pre-oxidized, the first time add KMnO₄, second of addition KMnO₄Added with third time KMnO₄Mass ratio be 1:2:3, the dried mixture and total KMnO₄Ratio be 1-2:10-15；

After the graphite mixture pre-oxidized is filtered and dried, it is positioned in Muffle furnace and is heated, heat treatment Temperature handles 15-20s, 20-30s is handled at 1180 DEG C, obtain expanding stone to handle 10-20s at 1100 DEG C at 1150 DEG C Ink；

Step 2, the made expanded graphite of step 1 is put into incubator and is warming up to 40 DEG C, react 3h, then, added and pre- Consistent amount of first distilled water of graphite mixture volume of oxidation, then reacts 2.5h, by incubator temperature to 40 DEG C, then Secondary addition after-fractionating water and H₂O₂10-60min is reacted, the amount of the after-fractionating water is 1-1.5 times of the first distilled water, the Two distilled water and H₂O₂Volume ratio be 4-20:1,10min, 8000~10000r/ of rotating speed is centrifuged after terminating in reaction Min, product is washed with hydrochloric acid solution after centrifugation, and the volume of the hydrochloric acid solution is the 10-50 of bulk product after centrifuging Times, finally dialyse 7-8 days and obtain graphite oxide；N- hydroxyls fourth two is added after graphite oxide is used into dimethyl sulfoxide ultrasonic dissolution Acid imide and self-control surface conditioning agent stir 2h at 35 DEG C, and product is filtered, washed, dried, that is, is surface-treated Graphite oxide；

Step 3, surface grafting, by the graphite oxide being surface-treated obtained by step 3 and the mixed with polymers of required grafting, and It is heated to 80-95 DEG C and is passed through nitrogen, and adds the solution containing tetravalence cerium ion, stirring reaction 2-4h, filtered, washing, Dry, obtain the polymer grafting graphite oxide, the mass ratio of the graphite oxide and the polymer of required grafting is 1-2： 1-3, the polymer of required grafting is by methyl methacrylate, GMA, dimethylaminoethyl Ethyl ester and diethylaminoethyl methacrylate composition, the methyl methacrylate, GMA, methyl The mass ratio of dimethylaminoethyl acrylate and diethylaminoethyl methacrylate is 1:1:2:1；

Step 4, gather after the graphite 1-2g of the surface grafting obtained by step 2 is freezed dried at -10 DEG C with 1-10g Oxide-polypropylene oxide-PEO triblock copolymer is put into ultrasonic disperse in 500ml ethylene glycol and formed in the lump Uniform first dispersion liquid；Simultaneously by 4-15g by FeCl₃·6H₂O、FeCl₂·4H₂O and acetyl acetone iron composition mixing Thing, 6~25g polyvinylpyrrolidones and 10~50g NH₄It is scattered that Ac is dissolved in formation second in 500-1000mL ethylene glycol Liquid, the first dispersion liquid and the second dispersion liquid are mixed, and adjusted with ammoniacal liquor, it is molten to make the clarification that pH value is 8-10 Liquid, the FeCl₃·6H₂O、FeCl₂·4H₂The mass ratio of O and acetyl acetone iron is 1:1:0.5；

Step 5, the settled solution obtained by 100ml step 3 is put into reactor, after sealing, is heated to 150 DEG C, protects Warm 2h, 200 DEG C are warming up to 2-4 DEG C/min heating rate afterwards, 4h are incubated, afterwards with 3-6 DEG C/min heating rate liter Temperature is incubated 3h to 235 DEG C, then 200 DEG C of insulation 2h is cooled to 5-7 DEG C/min cooling rate, finally again with 3-6 DEG C/min Heating rate be warming up to 235 DEG C, be incubated 7h, after the completion of question response, reactor taken out, is allowed to be cooled to room temperature, the drop Warm speed is 3-6 DEG C/min, and the black powder of gained centrifuged into 10min, 8000~10000r/min of rotating speed, and use is anhydrous Respectively washing three times, is dried in vacuo 24h at 50~70 DEG C, obtains the first product for ethanol and deionized water；

The products of 5g first and 5-10g aniline monomers are added into the solution of DBSA, ultrasonic disperse 65min, shape Into the second product, the mass ratio of first product and DBSA is 1-1.5:8-15；

3g ammonium persulfates are dissolved in 80-120ml distilled water, are slowly dropped in the second product, stirring reaction 15h, reaction After end, filter, it is colourless to filtrate with distilled water, ethanol washed product respectively, 50~70 DEG C of 24~36h of vacuum drying, obtain Nano combined absorbing material；

Absorber Bandwidth of the absorbing material below reflection loss -10dB is 4.8-5.1GHz.
2. absorbing material according to claim 1, it is characterised in that graphite oxide g described in step 2, dimethyl sulfoxide Ml, N- hydroxysuccinimide g and self-control surface conditioning agent g ratio are 0.2-0.5：20-25：2-5：0.1-05, it is described from Control surface inorganic agent is made up of dicyclohexylcarbodiimide, dodecyl sodium sulfate, kayexalate and polyacrylic acid, institute The mass ratio for stating dicyclohexylcarbodiimide, dodecyl sodium sulfate, kayexalate and polyacrylic acid is 1:1:2:3.
3. absorbing material according to claim 1, it is characterised in that the concentration of hydrochloric acid is body in the described step 2 Product ratio 1:10 hydrochloric acid solution.