Preparation of CIP/SiO2/PANI Composites and Design of Electromagnetic Wave Absorption Coating in X-Band

2013 ◽  
Vol 846-847 ◽  
pp. 1905-1910
Author(s):  
Ming Ming Wang ◽  
Wan Jun Hao ◽  
Zhong Lun Zhang ◽  
Guo Yan Hou ◽  
Zhi Jun Xin ◽  
...  

CIP particles first have been coated with SiO2 shell by a Stober process , then grafted the polyaniline by in-situ polymerization to prepare CIP/SiO2/PANI core-shell composites, and the composites are composed the dielectric loss properties with the magnetic loss properties. It is observed that PANI are on the surface of CIP/SiO2 particles from the SEM image, XRD patterns further confirm that the CIP/SiO2/PANI composites are synthesized successfully. In comparison with CIP, the complex permittivity of CIP/SiO2/PANI composites have certain enhancement in 8-12 GHz frequency range, but it has a very small impact on the complex permeability. On the basis of the Electromagnetic Wave Absorbing Theory, the composites could prepare high-performance absorbing coating based on λ/4 type design, and the coating is below-10dB in the whole X-band, which could be used for architectural space electromagnetic radiation protection.

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.


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.


2008 ◽  
Vol 8 (8) ◽  
pp. 3967-3972 ◽  
Author(s):  
Juanjuan Huang ◽  
Yong Qin ◽  
Jiangong Li ◽  
Xingdong Jiang ◽  
Fei Ma

The Ni nanoplatelets with an average diameter of 75 nm and an average thickness of 10 nm are coated with MnO2 by a simple solution phase chemical method. The MnO2-coated Ni nanoplatelets are dispersed in paraffin wax to form the composite samples of the magnetic filler dispersed in the nonmagnetic insulating matrix. The effect of the Ni nanoplatelet volume fraction on the complex permittivity, complex permeability, and microwave absorption of the composites has been studied in the frequency range of 0.1–10 GHz. The complex permittivity of the composites with different volume fractions of the Ni nanoplatelets is almost constant in the 0.1–10 GHz frequency range. The complex permeability of the composites shows several resonance peaks. Besides the natural resonance peak, the exchange resonance peaks are observed. The composite with 17% volume fraction of Ni nanoplatelets has excellent microwave absorption properties of a minimum reflection loss value −31 dB at 9.1 GHz for a thickness of 2 mm and a broad absorption bandwidth of 2.3–10 GHz (R < −10 dB). The Ni nanoplatelets are a possible candidate as high performance microwave absorption filler. For the Ni nanoplatelet composites, the magnetic loss is the dominant term for microwave absorption.


Author(s):  
Xiaojuan Shen ◽  
Xuan Zhang ◽  
Tongfei Wang ◽  
Songjun Li ◽  
Zhaoqiang Li

In this study, a novel 3D porous Si-based supercapacitor electrode was developed by the simple solution method, which involved firstly the in-situ polymerization of polyaniline particles (PANI) on the Si...


2019 ◽  
Vol 361 ◽  
pp. 897-907 ◽  
Author(s):  
Jingchun Lv ◽  
Peiwen Zhou ◽  
Linping Zhang ◽  
Yi Zhong ◽  
Xiaofeng Sui ◽  
...  

2021 ◽  
Vol 31 (4) ◽  
pp. 249-255
Author(s):  
Zuoqun Zhang ◽  
Chaoshan Yang ◽  
Hua Cheng ◽  
Xiaohan Huang ◽  
Yuhao Zhu

Now there’re many researches on the electromagnetic radiation protection function of the cement-based electromagnetic wave absorbing materials, such materials have been widely used in various types of buildings. This paper proposed an idea for preparing a cement-based composite material by mixing functional aggregates with high content of Fe2O3 and SiC, that is, adding Fe3O4 powder and nano-SiC of different contents in the clay, and then sintering at 1190℃; the prepared aggregates showed obvious magnetic loss and dielectric loss to electromagnetic waves, and the numerical tube pressure could reach 16.83MPa. The double-layer reflectivity test board made of functional aggregates showed excellent electromagnetic wave absorption performance, its reflection loss was less than -10dB in the frequency range of 8~18GHz (corresponding to energy absorption greater than 90% EM), and its maximum RL reached -12.13dB. In addition, the compressive strength of the cement-based composite material at the age of 28 days reached 50.1 MPa, which can meet the strength requirements of building materials.


Polymers ◽  
2019 ◽  
Vol 11 (6) ◽  
pp. 985 ◽  
Author(s):  
Yidong Liu ◽  
Lingfeng Jian ◽  
Tianhua Xiao ◽  
Rongtao Liu ◽  
Shun Yi ◽  
...  

CO2 has been regarded as one of the most promising blowing agents for polystyrene (PS) foam due to its non-flammability, low price, nontoxicity, and eco-friendliness. However, the low solubility and fast diffusivity of CO2 in PS hinder its potential applications. In this study, an attapulgite (ATP)/polypyrrole (PPy) nanocomposite was developed using the in situ polymerization method to generate the hierarchical cell texture for the PS foam based on the supercritical CO2 foaming. The results demonstrated that the nanocomposite could act as an efficient CO2 capturer enabling the random release of it during the foaming process. In contrast to the pure PS foam, the ATP/PPy nanocomposite reinforced PS foam is endowed with high cell density (up to 1.9 × 106) and similar thermal conductivity as the neat PS foam, as well as high compression modulus. Therefore, the in situ polymerized ATP/PPy nanocomposite makes supercritical CO2 foaming desired candidate to replace the widely used fluorocarbons and chlorofluorocarbons as PS blowing agents.


2013 ◽  
Vol 774-776 ◽  
pp. 747-752 ◽  
Author(s):  
Yue Fang Zhang ◽  
Wan Jun Hao ◽  
Bao Yi Li ◽  
Yu Ping Duan ◽  
Shun Hua Liu

This paper reported that, using the method of double layer composite successfully prepared high performance of electromagnetic wave absorption materials. Such a composite is composed of a cement matching layer filled with expanded polystyrene (EPS) beads and an absorbing cement layer made of EPS beads and carbon black. The samples were tested by arching method in the frequency range of 8~18GHz. The reflectivities were revealed to be excellent, the lowest being-17dB. The new material can be used for building indoor electromagnetic radiation protection.


2014 ◽  
Vol 989-994 ◽  
pp. 164-167
Author(s):  
Rui Feng

An in-situ polymerization method was used for the preparation of a novel stir bar based on neodymium magnet (Nd2Fe14B) powders. The processes were carried out by several steps including the enwrapping of Nd2Fe14B, the modification of the enclosed Nd2Fe14B, and the form of organic polymers on the surface of the modified powders. It was successfully used to enrich the plasticizers in water sample by stir bar sorptive extraction (SBSE). The experimental conditions for SBSE, such as the choice of extraction sorvents, salt concentration, extraction and desorption time were optimized in detail. Coupled to high performance liquid chromatography (HPLC), the recoveries of dibutyl phthalate (DBP), dimethyl phthalate (DMP), diethyl phthalate (DEP) were 89.2%~92.1%, 91.9%~96.6% and 94.3%~96.7%, respectively; the linear relationships between the concentration 5 μg/L and 800 μg/L for DBP were obtained; the limits of detection ranged from 0.09 μg/L to 0.21 μg/L in the optimal conditions.


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