Electromagnetic Properties of Polyaniline Co-Doped with CSA and Ni2+

2011 ◽  
Vol 194-196 ◽  
pp. 2268-2271
Author(s):  
Shi Bu Zhu ◽  
Man Jiang ◽  
An Zhao ◽  
Wei Wei ◽  
Zuo Wan Zhou

In this work, polyaniline co-doped with (IS)-(+)-10-camphorsulfonic acid (D-CSA) and Ni2+was synthesized viain situpolymerization. The structure, conductivity and electromagnetic parameters of the resulting polyaniline were characterized by FTIR, SZ82 digital multimeter and AV3618 network analyzer. The conductivity of polyaniline at room temperature increases with increasing of Ni2+loading. Moreover, the resulting polyaniline co-doped with Ni2+displays obvious magnetic loss at the microwave frequency. So, we suppose that this conducting polymer can be used as microwave absorbing material with wide-range and good effect.

2013 ◽  
Vol 834-836 ◽  
pp. 187-190
Author(s):  
Ming Ming Wang ◽  
Zhong Lun Zhang ◽  
Wan Jun Hao ◽  
Guo Yan Hou ◽  
Zhi Jun Xin ◽  
...  

CIP particles first were coated with SiO2 shell by the Stober process , then grafted the polyaniline by in-situ polymerization to prepare CIP/SiO2/PANI core-shell composites. The CIP/SiO2/PANI composites are composed the dielectric loss properties with the the magnetic loss properties, the morphologystructure and electromagnetic properties are characterized by SEMXRD and vector network analyzer, respectively. It is observed that SiO2 and PANI are on the surface of CIP particles, XRD patterns further confirm that the CIP/SiO2/PANI composites are synthesized successfully, and that interaction between components exist in the polymerization. In comparison with CIP, the complex permittivity of CIP/SiO2/PANI composites have certain enhancement in 2-18GHz frequency range, but it has a very small impact on the complex permeability.


2019 ◽  
Vol 2019 ◽  
pp. 1-9
Author(s):  
Di Zhang ◽  
Huaiyin Chen ◽  
Ruoyu Hong

In this paper, the magnetite/polyaniline (PANI) nanocomposite was prepared by the novel reverse in situ polymerization method. Fe3O4 magnetic nanoparticles were synthesized in situ in PANI chloroform solution to form a suspension containing the Fe3O4/PANI nanocomposite. It overcame the disadvantage of oxidation of the Fe3O4 by the oxidant in conventional method. The Fe3O4/PANI chloroform suspension and the Fe3O4/PANI powder were characterized by FT-IR, TEM, XRD, vibrating sample magnetometer, Gouy magnetic balance, conductivity meter, and vector network analyzer. It is demonstrated that the Fe3O4/PANI suspension has a good electrical conductivity that is up to 2.135 μS/cm at the optimal ratio of reactants. The Fe3O4 nanoparticles are well dispersed in the PANI network with a particle size of about 10 nm. Fe3O4/PANI powder has high saturation magnetization and magnetic susceptibility, as well as a broad application prospect in the field of electromagnetic devices. The Fe3O4/PANI powder exhibits an excellent microwave absorption behavior, which can be an outstanding candidate for the rapid development of broadband shielding materials.


2020 ◽  
Vol 186 ◽  
pp. 03006
Author(s):  
Lan Tian ◽  
Dong Lichao ◽  
Li Nan ◽  
Zhang Chunbo ◽  
Zhang Hao ◽  
...  

Microwave absorbing material was prepared using epoxy resin as matrix and spherical carbonyl iron powder (s-CIP), flaky carbonyl iron powder (f-CIP) as absorbing agent. Microwave absorbing, mechanical properties and structure of the composites containing different kinds of carbonyl iron powder (CIP) were investigated. The results show that the microwave absorber with flaky CIP have better electromagnetic properties than composites with spherical CIP. With concentration of spherical CIP increasing the electromagnetic properties of composites becomes better, except for the mechanical performance. The flaky CIP/epoxy resins composites with a loading of 79 wt% plate-like CIP has attenuation constant of 25.443 dB/cm in 3 GHz. The absorber prepared using flaky CIP has homogenous, dense structure and has excellent mechanical properties.


2011 ◽  
Vol 295-297 ◽  
pp. 249-255
Author(s):  
Ke Yu Chen ◽  
Meng Xi Sun ◽  
Liang Chao Li ◽  
Feng Xu ◽  
Qiu Shi Xiao

The poly(o-toluidine)/BaFe10Al2O19 (POT/BFA) composites were synthesized by in-situ polymerization of o-toluidine in the presence of BaFe10Al2O19 particles. The structure, composition and morphology and electromagnetic property of the obtained samples were characterized by means of modern testing techniques. The results indicated that BFA particles were coated effectively by POT polymer chain and some interactions between POT and BFA particles were existed in the composites. The conductivity and saturation magnetization of POT/BFA composites were smaller than those of pure polymers and pure BFA respectively. The POT/BFA composites had excellent magnetic loss (μ′′) and dielectric loss (ε′′) in the range of 1 MHz~3 GHz because of their intrinsic properties and synergistic effect between components. Hence, they could be recommended as candidates for electromagnetic wave absorption and shielding materials.


2018 ◽  
Vol 7 (6) ◽  
pp. 487-492 ◽  
Author(s):  
Bashir Ahmad Dar ◽  
Zahed Zaheer ◽  
Samreen Fatema ◽  
Mazahar Farooqui

Abstract An easy and efficient scheme is described and designed for the preparation of 4,5-dihydro-1,2,4-oxadiazole using recyclable Cu(OH)x-clay heterogeneous catalyst at room temperature. The cycloaddition reaction is carried out between imine and oxime using an easy protocol where nitrile oxides are produced in situ from aldoximes and reacted with imines to form 1,2,4-oxadiazolines in good yield and tremendous purity. Cu(OH)x-clay catalyst shows excellent catalytic activity for the formation of 1,2,4-oxadiazole. This technique is practically uncomplicated, inexpensive, and excellent with a wide range of functional group tolerance to generate structurally different 1,2,4-oxadiazoles. The prepared catalyst was investigated by X-ray diffraction and scanning electron microscopy techniques. The final products of the synthesized compound were characterized by Fourier transform infrared, mass, and nuclear magnetic resonance spectroscopies.


2017 ◽  
Vol 268 ◽  
pp. 297-301 ◽  
Author(s):  
Yau Thim Ng ◽  
Wei Kong ◽  
Sivanesan Appadu ◽  
Ing Kong

Magnetite (Fe3O4)-graphene nanohybrids having three different weight ratios of magnetite to graphene were synthesized by a facile in-situ deposition method. The combination of dielectric properties of graphene and magnetic properties of magnetite makes the nanohybrids an ideal choice of material for microwave absorption applications. In regards to that, the electromagnetic properties and microwave absorbing characteristics were investigated in a frequency range of 1-18 GHz. The reflection loss (RL) reaches a minimum of-40.44 dB at 6.84 GHz with a thickness of 7 mm for the sample containing 73 wt·% of Fe3O4. The bandwidth corresponding to the RL below-10 dB is 7.05 GHz. The as-prepared Fe3O4-graphene nanohybrids showed good microwave absorption ability in the low frequency band (C-band) which can be ascribed to improved impedance matching characteristics, enhanced interfacial polarizations as well as the magnetic loss contributions. Moreover, the frequency related to minimum RL could be tuned by varying the weight ratios of magnetite to graphene.


2013 ◽  
Vol 329 ◽  
pp. 18-21 ◽  
Author(s):  
P. Cao ◽  
Y. Bai

Zinc oxide materials with outstanding performance are the broadband gap semiconductor, and make it a number of important subjects and a wide range of applications. In this paper, a Co-doped ZnO film grown by electrodeposition shows room-temperature ferromagnetic properties after the ammine plasma treatment. The XPS spectra show that the Co ions have a chemical valence of 2+ and a few nitrogen atoms was incorporated into ZnCoO film during the treatment process to occupy oxygen positions. The electronic properties also give evidence that nitrogen is incorporated into ZnCoO film. So the ferromagnetism is mediated though the p-d exchange interaction between nitrogen induced carriers and Co atoms.


2014 ◽  
Vol 1081 ◽  
pp. 308-312
Author(s):  
Jun Ji Wei ◽  
Zi Cheng Wang ◽  
Hai Long Tang ◽  
Xiao Bo Liu

A new kind of organic prepolymer containing cobalt phthalocyanine ring (Co-FOM) was prepared by reaction from ferrocenyl organic magnetic prepolymer (FOM) and cobalt chloride. The structure of Co-FOM was characterized by Fourier transform infrared spectroscopy (FTIR) and ultraviolet-visible spectrophotometry (UV-vis). The magnetic properties of Co-FOM exhibited stronger magnetism than FOM at room temperature. The maximum saturation magnetization of Co-FOM reached to 15.8 emu/g at the magnetic field of 5000 Oe. Meanwhile, Co-FOM had one resonance peak for dielectric loss and two resonance peaks for magnetic loss in 0.5-18 GHz. Furthermore, this kind of magnetic material had a strong reflection loss at higher frequency (around 17 GHz). So Co-FOM will have potential application in electromagnetic shielding area.


2007 ◽  
Vol 534-536 ◽  
pp. 1449-1452 ◽  
Author(s):  
Byoung Yoon Lee ◽  
Jae Wook Lee ◽  
Yeo Chun Yun ◽  
In Bum Jeong ◽  
Joo Ho Moon

The synthesis of silver coated iron base alloy (Sendust : Fe-Si-Al) powder having the both effects of shielding and suppressing of electromagnetic wave was studied. Depending on thickness of silver coating layer, the electromagnetic properties of the dispersed particles complexed with organic binder were examined. EDS-SEM, XRD, ohm meter, network analyzer (PNA8364A) measurements were used to characterize the electromagnetic properties. The silver coated powders have a better microwave absorbance than non coated powder in the low frequency range of below 1.0GHz, which is due to a high dielectric constant and dielectric loss of the silver in microwave frequencies magnetic loss in addition to conduction loss. Reflection loss of the 5% silver containing composite was found to be –6 dB at 1.0GHz with 1.0mm thickness. It is, therefore, successfully proposed that the silver coated sendust flake powders with controlled electrical properties and thickness can be used as thin microwave absorbers in quasi-microwave frequency band.


Author(s):  
Ernest L. Hall ◽  
J. B. Vander Sande

The present paper describes research on the mechanical properties and related dislocation structure of CdTe, a II-VI semiconductor compound with a wide range of uses in electrical and optical devices. At room temperature CdTe exhibits little plasticity and at the same time relatively low strength and hardness. The mechanical behavior of CdTe was examined at elevated temperatures with the goal of understanding plastic flow in this material and eventually improving the room temperature properties. Several samples of single crystal CdTe of identical size and crystallographic orientation were deformed in compression at 300°C to various levels of total strain. A resolved shear stress vs. compressive glide strain curve (Figure la) was derived from the results of the tests and the knowledge of the sample orientation.


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