CN105062092A - Chiral poly(Schiff base) salt ternary composite wave absorbing material - Google Patents

Abstract

The invention relates to a chiral poly(Schiff base) salt ternary composite wave absorbing material. 100 Parts by mass of an absorbing medium comprise 11-17 parts by mass of carbon nanotubes, 45-65 parts by mass of cobalt-nickel ferrite and 18-44 parts by mass of a chiral poly(Schiff base) salt. A mass ratio of the absorbing medium to the chiral poly(Schiff base) salt ternary composite wave absorbing material is 1:2-4:5, and a mass ratio of a paraffin matrix to the chiral poly(Schiff base) salt ternary composite wave absorbing material is 1:2-5. The composite wave absorbing material has the advantages of lightweight, thin layer, wide absorption frequency band, large absorption intensity and good stability, has a good wave absorbing effect in a frequency band of 8-18GHz, and has important application values in electromagnetic pollution treatment and radar stealth.

Description

A kind of chirality gathers Schiff salt tri compound absorbing material

Technical field

The present invention is that a kind of chirality gathers Schiff salt tri compound absorbing material, and particularly a kind of carbon nanotube/cobalt nickel ferrite/chirality gathers the absorbing material of Schiff salt tri compound, is a kind of Radar Stealth Composites, belongs to absorbing material technical field.

Background technology

Absorbing material refers to and can absorb the electromagnetic wave energy projecting its surface, and makes electromagnetic wave energy be converted into a class material of the energy of heat energy or other form by the dielectric loss of material.The features such as absorbing material general requirement absorbs by force, bandwidth, quality are light and structure properties is stable under used environment, conventional absorbing material mainly contains: ferrite, metal fine powder, semiconductor material, conduction high polymer, carbon fiber, polycrystalline iron fiber etc.At present, traditional both at home and abroad invisible coating exists a large amount of outstanding problem to be had to be solved: narrower absorption frequency range cannot resist the comprehensive scouting of wide-band radar wave; The density of material thickness that is large and coating is large, adds system weight, the maneuvering ability of influential system.Publication number is CN101203127A, a kind of rare earth Fe basis suction wave material by name and preparation method thereof, and the matching thickness that this material uses when absorbing the most by force is up to 6mm, there is the shortcoming that coat-thickness is large; Publication number is CN1206204A, a kind of novel wave-absorbing material by name and manufacture method thereof, disclose the treated electromagnetic wave absorbent material made such as a kind of ferrite magnetic material and zinc, cobalt, copper, this material has stronger microwave absorbing property at low-frequency range 0.6GHz – 5GHz, 93.7% is reached in the specific absorption of mid-frequency 3.5GHz, but poor at high band 8 – 18GHz wave-absorbing effect, and material is made up of metal oxide and metal, density is large; Publication number is CN101914722A, and a kind of electromagnetic wave absorbent material by name, discloses a kind of Nd _1-xsm _xfe ₁₄b and matrix material mix the matrix material that the process of merga pass magnetic field orientating is made, this material has strong absorption at low-frequency range 1 – 8GHz, and poor at high band 8 – 18GHz wave-absorbing effect, and material has main component to be rare-earth iron-boron alloy, there is the shortcoming that density is large equally.Publication number is CN103555270A, a kind of chirality polyShiff base salt/ferrite wave-absorbing material by name and preparation method thereof, disclose a kind of chirality binary composite wave-suction material, this material has reflection loss at 8 – 18GHz to hertzian wave, maximum reflection loss is-17.2dB, but suction intensity of wave is still little.

Chirality absorbing material, compared with conventional absorbing material, has three distinguishing features: one is the cross polarization of electromagnetic field, strengthens electromagnetic absorption intensity; Two are adjustment chirality parameters than adjust dielectric parameter and magnetic permeability easy, no reflection events requirement can be met on wider frequency band; Three be chiral material frequency sensitivity than specific inductivity and magnetic permeability little, easily realize wideband absorb.Therefore inhale in ripple frequency band in raising absorbing property, expansion there is very large potential.Chirality tri compound absorbing material in the present invention has most strong reflection loss-33.3dB at frequency 13.2GHz, thickness 1.5mm place, and the suction ripple frequency range that reflection loss reaches below-5dB is 7.6GHz (10.4 – 18GHz).Contrast above-mentioned several patent, chirality tri compound absorbing material thickness in the present invention is little, have strong absorption at high band 8 – 18GHz, absorb the most by force and can reach-33.3dB, and contained chirality to gather Schiff be low-density organic materials, solve that usual absorbing material thickness is large, high band 8 – 18GHz absorption difference, problem that density of material is large, therefore this chirality composite wave-suction material has the performance more excellent than existing absorbing material.

Summary of the invention

In order to overcome above-mentioned the deficiencies in the prior art, the invention provides a kind of chirality and gathering Schiff salt tri compound absorbing material.The absorbing medium of described composite wave-suction material gathers Schiff salt three by carbon nanotube, cobalt nickel ferrite and chirality and forms, and the mass ratio that carbon nanotube, cobalt nickel ferrite, chirality gather Schiff salt and absorbing medium is respectively 11 ~ 17:100,45 ~ 65:100 and 18 ~ 44:100; The mass ratio that absorbing medium and chirality gather Schiff salt tri compound absorbing material is 1:2 ~ 4:5, and the mass ratio that paraffin matrix and chirality gather Schiff salt tri compound absorbing material is 1:2 ~ 5.

Preparation process is as follows:

(1) carbon nanotube and mixing acid are according to the ratio of 1g/100mL, in carbon nanotube, add mixing acid, ultrasonic disperse 30 minutes, heat, stir, reflux 4 hours at 70 DEG C; Reaction terminates rear ice-water bath and is cooled to no longer include red cigarette and emerges, and leaves standstill 24 hours thereafter, and after pouring out supernatant liquid, suction filtration, with deionized water wash to filtrate pH=7, gained filter cake at 100 DEG C dry 24 hours, obtains the carbon nanotube of purifying.

(2) CoCL2 6H2O, six water nickelous chlorides and Anhydrous Ferric Chloride are dissolved in deionized water by the mol ratio of 1:1:4, add the carbon nanotube of sodium oleate and purifying more respectively, stir 1 hour, then 75 DEG C are warming up to, condensing reflux, and slowly drip sodium hydroxide solution to pH value of solution=11, continue reaction 1 hour; Be transferred to by reaction solution in water heating kettle, react after 12 hours at 180 DEG C, then standing cooling filters, and after filter cake uses water, absolute ethanol washing to pH=7 respectively, then obtains carbon nanotube/cobalt nickel ferrite after dry 12 hours at 70 DEG C.

(3) by 1B and KOH in molar ratio 1:1 add in dehydrated alcohol, after 50 DEG C of lower magnetic force stirring and dissolving, slowly drip the ethanol solution of para benzoquinone again, maintain reaction system under the condition of 80 DEG C of water-baths, nitrogen protection and condensing reflux, magnetic agitation adds silver nitrate aqueous solution after reacting 22 hours, continues reaction 6 hours; Carry out suction filtration after reaction terminates, filter cake 75 DEG C of dryings 7 hours, obtains chirality and gathers Schiff salt after using deionized water, absolute ethanol washing 3 times respectively.

(4) carbon nanotube/cobalt nickel ferrite, chirality are gathered Schiff salt and added in dehydrated alcohol, supersound process 6 hours, reheat solvent evaporated, thereafter the dryings in 12 hours more respectively at 70 DEG C, the milled processed of 20 minutes, carbon nanotube/cobalt nickel ferrite/the chirality obtained is gathered Schiff salt tri compound and is inhaled ripple medium and paraffin body material according to mass ratio 7:3, heated and stirred mixes, and obtained chirality gathers Schiff salt tri compound absorbing material.

Described mixing acid is the mixture of the vitriol oil and concentrated nitric acid, and the volume ratio of the vitriol oil and concentrated nitric acid is 3:1.

The mol ratio of described 1B, para benzoquinone and Silver Nitrate is 1:1:1.5.

Described chirality gathers mass ratio 1:1 ~ 5 of Schiff salt and carbon nanotube/cobalt nickel ferrite.

Advantage of the present invention

The present invention has that light weight layer is thin, absorption band is wide, the advantages such as absorption intensity is large, good stability.It is a kind of containing chirality conductive polymers that chirality gathers Schiff salt, and the conductivity of poly-Schiff can carry out dielectric loss to hertzian wave, and the spirane structure of chiral material can cause electromagnetic cross polarization, easily realizes wideband absorb by regulating chirality parameter.Carbon nanotube/cobalt nickel ferrite is the absorbing material having resistive losses and magnetic loss concurrently, chirality is gathered Schiff salt and carbon nanotube/cobalt nickel ferrite compound can realize electromagnetic impedance match, by their synergistic function, at frequency range 8 – 18GHz, there is good wave-absorbing effect, in improvement electromagnetic pollution and radar invisible, there is important using value.

Accompanying drawing explanation

Fig. 1 is the wave-absorbing effect figure of the embodiment of the present invention 1;

Fig. 2 is the wave-absorbing effect figure of the embodiment of the present invention 2;

Fig. 3 is the wave-absorbing effect figure of the embodiment of the present invention 3.

Embodiment

Embodiment 1

(1) get 2.00g carbon nanotube and be placed in there-necked flask, add 200mL nitration mixture (dense H ₂sO ₄/ dense HNO ₃=3:1), ultrasonic disperse 30 minutes, heats, stirs, refluxes 4 hours at 70 DEG C.After reaction terminates, reaction solution to be poured in beaker and be put in ice-water bath and cool, add cold water until no longer include red cigarette and emerge.Leave standstill 24 hours, pour out supernatant liquid, suction filtration with deionized water repetitive scrubbing to filtrate pH=7, to put at 100 DEG C, baking oven dry 24 hours, obtain the carbon nanotube of purifying.

(2) 4.87g Anhydrous Ferric Chloride, 1.78g CoCL2 6H2O, 1.78g six water nickelous chloride is got, be dissolved in 150mL deionized water, be to be dissolvedly placed in 500mL there-necked flask, add 0.125g sodium oleate, add the carbon nanotube of 0.75g purifying, stir 1 hour.Then be warming up to 75 DEG C, condensing reflux, slowly drip the sodium hydroxide solution of 3mol/L to pH value of solution=11, continue reaction 1 hour.Reaction solution to be transferred in water heating kettle at 180 DEG C and to react 12 hours, with water and dehydrated alcohol repetitive scrubbing to pH=7, at 70 DEG C dry 12 hours, obtain carbon nanotube/cobalt nickel ferrite matrix material.

(3) in 250mL there-necked flask, add 1.46gmolL-Methionin and 0.56gmolKOH, be dissolved in 20mL dehydrated alcohol, 50 DEG C of lower magnetic force stirring and dissolving.Ethanol solution 30mL being dissolved with 0.01mol para benzoquinone is slowly added drop-wise in above-mentioned mixed solution, stirs 22 hours at the condition lower magnetic force of 80 DEG C of water-baths, nitrogen protection and condensing reflux.Add the aqueous solution that 5mL is dissolved with 2.55g Silver Nitrate afterwards, continue reaction 6 hours.Suction filtration, filter cake deionized water and absolute ethanol washing 3 times, be placed in 75 DEG C of air dry ovens and dry 7 hours, obtain chirality and gather Schiff salt.

(4) get 3.20g carbon nanotube/cobalt nickel ferrite and 0.80g chirality to gather Schiff salt and be placed in beaker, add dehydrated alcohol ultrasonic 6 hours, heating solvent evaporated, to put at 70 DEG C, baking oven dry 12 hours, then grind 20 minutes, then stir with 1.71g heating paraffin and be mixed to get carbon nanotube/cobalt nickel ferrite/chirality and gather Schiff salt composite wave-suction material.

(5) this material is pressed in particular manufacturing craft the annulus of external diameter 7mm, internal diameter 3mm, thickness 2mm, with the electromagnetic parameter of HP-8722ES vector network analyzer test material, test frequency scope is 1 – 18GHz.Its absorbing property is estimated according to equation below: $\left(1\right)---Zin=\sqrt{\mathrm{\μ}r/\mathrm{\ϵ}r}\tanh \[j(2\mathrm{\π}fd/c)\sqrt{\mathrm{\μ}r\mathrm{\ϵ}r}\];$ (2)R _L(dB)＝20log|(Zin－1)/(Zin+1)|。This material, when thickness 1.5mm, has the reflection loss being less than-10dB within the scope of frequency 11.9 – 15.2GHz, obtains most strong reflection loss-33.2dB at frequency 13.2GHz place, and the wave-absorbing effect that this material simulation calculates is illustrated in fig. 1 shown below.

Embodiment 2

(1) step is with embodiment 1.

(2) step is with embodiment 1.

(3) step is with embodiment 1.

(4) get 3.20g carbon nanotube/cobalt nickel ferrite and 1.60g chirality to gather Schiff salt and be placed in beaker, add dehydrated alcohol ultrasonic 6 hours, heating solvent evaporated, to put at 70 DEG C, baking oven dry 12 hours, then grind 20 minutes, then stir with 2.06g heating paraffin and be mixed to get 6.86g carbon nanotube/cobalt nickel ferrite/chirality and gather Schiff salt composite wave-suction material.

(5) this material is pressed in particular manufacturing craft the annulus of external diameter 7mm, internal diameter 3mm, thickness 2mm, with the electromagnetic parameter of HP-8722ES vector network analyzer test material, test frequency scope is 1 – 18GHz.Its absorbing property is estimated according to equation below: $\left(1\right)---Zin=\sqrt{\mathrm{\μ}r/\mathrm{\ϵ}r}\tanh \[j(2\mathrm{\π}fd/c)\sqrt{\mathrm{\μ}r\mathrm{\ϵ}r}\];$ (2)R _L(dB)＝20log|(Zin－1)/(Zin+1)|。This material, when thickness 1.5mm, has the reflection loss being less than-10dB within the scope of frequency 12.6 – 15.6GHz, obtains most strong reflection loss-26.4dB at frequency 13.7GHz place, and the wave-absorbing effect that this material simulation calculates is illustrated in fig. 2 shown below.

Embodiment 3

(1) step is with embodiment 1

(2) step is with embodiment 1

(3) step is with embodiment 1

(4) get 2.40g carbon nanotube/cobalt nickel ferrite and 1.80g chirality to gather Schiff salt and be placed in beaker, add dehydrated alcohol ultrasonic 6 hours, heating solvent evaporated, to put at 70 DEG C, baking oven dry 12 hours, then grind 20 minutes, then stir with 1.80g heating paraffin and be mixed to get 6.00g carbon nanotube/cobalt nickel ferrite/chirality and gather Schiff salt composite wave-suction material.

This material is pressed in particular manufacturing craft the annulus of external diameter 7mm, internal diameter 3mm, thickness 2mm, with the electromagnetic parameter of HP-8722ES vector network analyzer test material, test frequency scope is 1 – 18GHz.Its absorbing property is estimated according to equation below: $\left(1\right)---Zin=\sqrt{\mathrm{\μ}r/\mathrm{\ϵ}r}\tanh \[j(2\mathrm{\π}fd/c)\sqrt{\mathrm{\μ}r\mathrm{\ϵ}r}\];$ (2)R _L(dB)＝20log|(Zin－1)/(Zin+1)|。This material, when thickness 1.3mm, has the reflection loss being less than-10dB within the scope of frequency 15.8 – 18.0GHz, obtains most strong reflection loss-18.2dB at frequency 17.3GHz place, and the wave-absorbing effect that this material simulation calculates is illustrated in fig. 3 shown below.

Note: this patent is subsidized by national natural science fund subsidy project (21264011) and aviation fund (2014ZF56020).

Claims (4)

1. a chirality gathers Schiff salt tri compound absorbing material, it is characterized in that the absorbing medium of described composite wave-suction material gathers Schiff salt three by carbon nanotube, cobalt nickel ferrite and chirality and forms, the mass ratio that carbon nanotube, cobalt nickel ferrite, chirality gather Schiff salt and absorbing medium is respectively 11 ~ 17:100,45 ~ 65:100 and 18 ~ 44:100; The mass ratio that absorbing medium and chirality gather Schiff salt tri compound absorbing material is 1:2 ~ 4:5, and the mass ratio that paraffin matrix and chirality gather Schiff salt tri compound absorbing material is 1:2 ~ 5;

Preparation process is as follows:

(1) carbon nanotube and mixing acid are according to the ratio of 1g/100mL, in carbon nanotube, add mixing acid, ultrasonic disperse 30 minutes, heat, stir, reflux 4 hours at 70 DEG C; Reaction terminates rear ice-water bath and is cooled to no longer include red cigarette and emerges, and leaves standstill 24 hours thereafter, after pouring out supernatant liquid, and suction filtration, with deionized water wash to filtrate pH=7, gained filter cake at 100 DEG C dry 24 hours, obtains the carbon nanotube of purifying;

(2) CoCL2 6H2O, six water nickelous chlorides and Anhydrous Ferric Chloride are dissolved in deionized water by the mol ratio of 1:1:4, add the carbon nanotube of sodium oleate and purifying more respectively, stir 1 hour, then 75 DEG C are warming up to, condensing reflux, and slowly drip sodium hydroxide solution to pH value of solution=11, continue reaction 1 hour; Be transferred to by reaction solution in water heating kettle, react after 12 hours at 180 DEG C, then standing cooling filters, and after filter cake uses water, absolute ethanol washing to pH=7 respectively, then obtains carbon nanotube/cobalt nickel ferrite after dry 12 hours at 70 DEG C;

(3) 1B and KOH in molar ratio 1:1 add in dehydrated alcohol, after 50 DEG C of lower magnetic force stirring and dissolving, slowly drip the ethanol solution of para benzoquinone again, maintain reaction system under the condition of 80 DEG C of water-baths, nitrogen protection and condensing reflux, magnetic agitation adds silver nitrate aqueous solution after reacting 22 hours, continues reaction 6 hours; Carry out suction filtration after reaction terminates, filter cake 75 DEG C of dryings 7 hours, obtains chirality and gathers Schiff salt after using deionized water, absolute ethanol washing 3 times respectively;

(4) carbon nanotube/cobalt nickel ferrite, chirality are gathered Schiff salt and added in dehydrated alcohol, supersound process 6 hours, reheat solvent evaporated, thereafter the dryings in 12 hours more respectively at 70 DEG C, the milled processed of 20 minutes, carbon nanotube/cobalt nickel ferrite/the chirality obtained is gathered Schiff salt tri compound and is inhaled ripple medium and paraffin body material according to mass ratio 7:3, heated and stirred mixes, and obtained chirality gathers Schiff salt tri compound absorbing material.

2. a kind of chirality according to claim 1 gathers Schiff salt tri compound absorbing material, it is characterized in that described mixing acid is the mixture of the vitriol oil and concentrated nitric acid, and the volume ratio of the vitriol oil and concentrated nitric acid is 3:1.

3. a kind of chirality according to claim 1 gathers Schiff salt tri compound absorbing material, it is characterized in that the mol ratio of described 1B, para benzoquinone and Silver Nitrate is 1:1:1.5.

4. a kind of chirality according to claim 1 gathers Schiff salt tri compound absorbing material, it is characterized in that: described chirality gathers mass ratio 1:1 ~ 5 of Schiff salt and carbon nanotube/cobalt nickel ferrite.