Synthesis and Microwave Absorption Characteristics of Polyaniline

2013 ◽  
Vol 327 ◽  
pp. 53-57 ◽  
Author(s):  
Ding Guo Li ◽  
Wen Hua Lu ◽  
Cong Chen ◽  
Wei Rao ◽  
Yong Hong Xiong

This paper aims at reporting the synthesis and microwave absorption characteristics of polyaniline (PANI). The PANI nanoparticles were synthesized by chemical oxidative polymerization method with ammonium persulfate ((NH4)2S2O8, APS) as oxidant and hydrochloric acid (HCl) for protonation of aniline. For APS/aniline mol ratio of 1, HCl concentration of 1 mol/L, reaction temperature of 5°C, the reaction time of 6h, the obtained PANI exhibits the highest value(30.9 S·cm-1)of the electrical conductivity. The structure and morphology of PANI were studied by X-ray diffraction (XRD), scanning electron microscopy (SEM), Fourier transform infrared spectrophotometer (FT-IR), ultraviolet-visible spectrophotometer (UV-Vis) analysis ways. Microwave absorbing performances were investigated using wave-guide method with vector network analyzer in 2–18 GHz. The results showed that there is a maximum absorption peak with RL= -12.63dB at 13.61GHz,the value of RL ≤−10 dB is maintained from 11.38GHz to 18GHz for the sample of the thickness for 2mm.

Author(s):  
R. K. Shukla ◽  
Susheel Kumar Singh ◽  
Akhilesh Tripathi

Polyaniline (PANI) is synthesized by chemical oxidative polymerization method. The, characterization were made using XRD (X-ray diffraction), FT-IR (Fourier transform spectroscopy), UV -vis (ultra-violet visible spectrophotometer) technique which confirms the synthesis of the Polyaniline. The surface morphology of Polyaniline was studied with scanning electron microscope (SEM).


2013 ◽  
Vol 631-632 ◽  
pp. 150-153
Author(s):  
Ji Wei Cai ◽  
Hai Jun Niu ◽  
Xu Duo Bai

Polypyrrole/montmorillonite (PPy/MMT) particles were synthesized using an oxidative polymerization method. Then the particles were added into polymethyl methacrylate (PMMA) as additives to prepare PPy/MMT/PMMA composite. The structures and properties of the composite were characterized by FT-IR, TGA, X-ray diffraction spectroscopy, and four–probe machine. The relationship between content of PPy/MMT and conductivity was analyzed. The result shows that the amount of PPy/MMT is a key factor for improving the conductivity of composite. Furthermore, dynamic mechanical (DM) properties of composite were studied. When the PPy/MMT content reach 0.2% of composite, the storage modulus, loss function modulus, dissipation factor get highest values.


2012 ◽  
Vol 581-582 ◽  
pp. 719-722
Author(s):  
Hui Huang ◽  
Ren Chun Fu ◽  
Zhong Cheng Guo

Polyaniline/tungsten carbide (PANI/WC) composite was synthesized by chemical oxidative polymerization of aniline using ammonium persulfate as the oxidant and thermal treated in air at 150°C, 250°C, 350°C and 450°C to 2 hours. The changes of structure, crystalline and conductivity were investigated by Fourier Transformed Infrared (FT-IR), Fourier Transformed Raman (FT-Raman), X-Ray Diffraction (XRD) and four-probe technique. The results showed that PANI/WC composite showed much-improved thermal stability compared to pure PANI. But the conductivity of PANI/WC is reduced to some extent (1.73 S/cm, the conductivity is reduced by about 82%) after thermal treated at 250°C, and dropped by 6 orders of magnitude (3.25×10-6S/cm) at 350°C. This may be explained by that only a fraction of dopant losses during thermal treatment at 250°C, but after thermal treatment at 350°C, along with cross-linking, chain scission and oxygen, resulting in destruction of crystal structure, decrease of the emeraldine sequence.


2022 ◽  
Vol 1048 ◽  
pp. 141-146
Author(s):  
Madihally Nagaraja ◽  
Geetha Thippeswamy ◽  
Sushma Prashanth ◽  
Jayadev Pattar ◽  
Mahesh Hampapatna Mahesh

Composite of polyaniline-MgCl has been synthesized using oxidative polymerization method. Synthesized samples were characterized for structural analysis using FTIR and XRD. Morphological studies were carried by SEM micrographs. Current-Voltage (I-V) properties are obtained through Kiethly source meter. FTIR spectrum of polyaniline-MgCl composite indicates all the characteristic peaks of polyaniline. X-ray diffraction patterns represented the amorphous nature of polyaniline-MgCl composite. SEM micrographs confirmed the presence of MgCl particles in polyaniline matrix. I-V characteristics have shown the ohmic type behavior of polyaniline and polyaniline-MgCl composite.


Author(s):  
Syed Shahabuddin ◽  
Norazilawati Muhamad Sarih ◽  
Muhammad Afzal Kamboh ◽  
Hamid Rashidi Nodeh ◽  
Sharifah Mohamad

The present investigation highlights the synthesis of polyaniline (PANI) coated graphene oxide doped with SrTiO3 nanocube nanocomposites through facile in-situ oxidative polymerization method for the efficient removal of carcinogenic dyes, namely, the cationic dye methylene blue (MB) and the anionic dye methyl orange (MO). The synthesised nanocomposites were characterised by field emission scanning electron microscopy (FESEM), transmission electron microscopy (TEM), thermogravimetric analysis (TGA), X-ray diffraction (XRD), and Fourier transform infrared spectroscopy (FTIR). The adsorption efficiencies of graphene oxide (GO), PANI homopolymer and SrTiO3 nanocubes-doped nanocomposites were assessed by monitoring the adsorption of methylene blue and methyl orange dyes from aqueous solution. The adsorption efficiency of nanocomposites doped with SrTiO3 nanocubes were found to be of higher magnitude as compared with undoped nanocomposite. Moreover, the nanocomposite with 2 wt% SrTiO3 with respect to graphene oxide demonstrated excellent adsorption behaviour with 99% and 91% removal of MB and MO respectively, in a very short duration of time.


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.


2008 ◽  
Vol 8 (9) ◽  
pp. 4743-4746 ◽  
Author(s):  
Haldorai Yuvaraj ◽  
Min Hee Woo ◽  
Eun Ju Park ◽  
Yeong-Soon Gal ◽  
Kwon Taek Lim

Poly(3-octylthiophene) (P3OT)-titanium dioxide (TiO2) nanocomposite powder where TiO2 was embedded with homogeneous dispersion was synthesized by in-situ chemical oxidative polymerization of 3-octylthiophene in the presence of TiO2 nanoparticles in supercritical carbon dioxide (scCO2), using ferric chloride as the oxidant. The synthesized materials could be obtained as dry powder upon venting of CO2 after the polymerization. The composites were subsequently characterized by FT-IR spectroscopy, transmission electron microscopy (TEM), X-ray diffraction studies (XRD), thermogravimetric analysis (TGA) and photoluminescence (PL). The incorporation of TiO2 in the composite was endorsed by FT-IR studies. TGA revealed enhanced thermal stability of P3OT/TiO2 nanocomposite compared to 3-octylthiophene. TEM analysis showed that well dispersed TiO2 nanoparticles in the polymer matrix. Photoluminescence quenching increased with increasing TiO2 concentration in the composite.


2019 ◽  
Vol 16 (1) ◽  
pp. 55-63
Author(s):  
Naglaa Shahin ◽  
Reham Kamal Abd El Hamid

Polyvinyl alcohol- polypyrrole (PVA-PPy) nanocomposites with metal chlorides (FeCl3, NiCl2, CuCl2 and ZnCl2) have been synthesized by chemical oxidative polymerization method. These synthesized nanocomposites are characterized by using FTIR, X-ray diffraction, Transition electron microscope (TEM) and Conductivity measurement. TEM exhibit that all of the composites have uniform sizes and morphologies.  The diameter of PVA/PPy nanocompsite is 58nm when the metals added to the PVA/PPy the diameters becomes smaller. The variation of electrical conductivity (log ?) with 1000/T for PVA/PPy nanocomposite with metal chlorides revealed that the increase in conductivity s at temperature (393K) with added metals can be attributed to the creation of induced charge carriers in PVA/PPy matrix


2021 ◽  
Vol 33 (12) ◽  
pp. 3075-3081
Author(s):  
K. Vinay ◽  
Y.T. Ravikiran ◽  
M. Revanasiddappa ◽  
A. Naveen Kumar ◽  
K. Veena ◽  
...  

In this work, the response of humidity sensing and dielectric properties of PANI/Ag/graphene/BaFe12O19 (PAGB) composite prepared by chemical interfacial oxidative polymerization method using the ammonium peroxydisulfate as an oxidant is presented. The synthesized PAGB composite was characterized by using FT-IR, XRD, SEM and EDAX techniques. The measured dielectric constant and dielectric tangent loss values were found to decrease with increase in logarithmic frequency. The electrical resistance of the composite was also found to decrease from 2500 MΩ to 7 MΩ, on exposure to a wide range of relative humidity (RH) varying between 10% and 97% RH. This observed decrease is due to capillary condensation of water molecules which cause the changes in electrical conductivity of composite. The synthesized PAGB-50% composite displayed a high sensitivity at low humidity ranging from 20% to 60% RH. The composite has been proved to be a better candidate in the design of humidity sensors. In addition, PAGB composite exhibited efficiency towards the degradation of organic anionic dye, acid orange-8, with high potential of reusability.


2018 ◽  
Vol 1 (1) ◽  
pp. 9-20 ◽  
Author(s):  
M Haridevi ◽  
S Prabu ◽  
M Lakshmi Devi ◽  
E Bhakya Lakshmi ◽  
K Mohanraj ◽  
...  

The Co3O4-PANI nanocomposites has been synthesized by chemical oxidative polymerization method using cobalt chloride. It is a simple and low cost method to prepare nanocomposite. The prepared samples were characterized by using Scanning Electron Microscope (SEM), X-ray diffraction (XRD) and Fourier Transform Spectroscopy (FTIR) to get surface morphology, idea of getting particles of nano sized range so that further characterization can be done, to study the net surface charge of the nanoparticles by Zeta potential, photoluminescence of synthesized nanocomposite and measure photocatalytic activity of the synthesized nanomaterials was successfully tested for photo degradation of dye under UV light were studied


Sign in / Sign up

Export Citation Format

Share Document