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Zhao X.,Jiangsu Polytechnic University | Zhao X.,Key Laboratory of Polymer Materials | Long R.,Jiangsu Polytechnic University | Chen Y.,Jiangsu Polytechnic University | Chen Z.,Jiangsu Polytechnic University
Microelectronic Engineering | Year: 2010

SiO2 ultrafine spheres are prepared by sol-gel method using tetraethylorthosilicate and ammonia as raw materials. CeO2-coated SiO2 (CeO2@SiO2) composite nanoparticles are also synthesized through chemical precipitation method. X-ray diffraction (XRD), scanning electron microscopy (SEM), transmission electron microscopy (TEM), X-ray photoelectron spectrometer (XPS) and dynamic light scattering (DLS) are used to characterize the CeO2@SiO2 composite particles. Silicon wafer covered by thermal oxide film is polished by CeO 2@SiO2 composite abrasives, and the polishing behavior of novel composite abrasives is characterized by atomic force microscope (AFM). The results indicate that the phases of the as-prepared CeO2@SiO 2 composite particles are composed of cubic fluorite CeO2 and amorphous SiO2. CeO2@SiO2 composite particles have excellent spherical morphologies and uniform particle size of 150-200 nm. The particle size of CeO2 as shell is about 10 nm. After coating, the chemical state of SiO2 is changed due to the formation of Si-O-Ce bond. The root-mean-square (RMS) roughness within 10 × 10 μm2 area of thermal oxide film after polished by CeO 2@SiO2 composite abrasives is 0.428 nm, and material removal rate can reach 454.6 nm/min. © 2009 Elsevier B.V. All rights reserved. Source


Chen Y.,Jiangsu Polytechnic University | Chen Y.,Key Laboratory of Polymer Materials | Long R.-W.,Jiangsu Polytechnic University | Chen Z.-G.,Jiangsu Polytechnic University | And 2 more authors.
Mocaxue Xuebao/Tribology | Year: 2010

Polystyrene (PS) microsphere prepared by soap-free emulsion polymerization was coated with CeO2 by chemical precipitation. As-prepared samples were analyzed by X-ray diffraction (XRD), transmission electron microscopy (TEM), selected area electron diffraction (SAED), field emission scanning electron microscopy (FESEM), energy dispersive analysis of X-rays (EDAX). Thermal oxide film on top of silicon wafer was polished by PS/CeO2 composite abrasives. The polished silicon wafer surface by novel composite abrasives was characterized by atomic force microscopy (AFM). The results indicated that core-shell PS/CeO2 composite particles with the diameters of 250~300 nm possessed a 10~20 nm thin shell that was composed of uniformly packed CeO2 nanoparticles (particle diameter of 5~10 nm). Ra and RMS(root-mean-square) within 5 μm × 5 μm area of thermal oxide film surface polished by PS/CeO2 composite abrasives were 0.188 nm and 0.238 nm, respectively. The material removal rate was 461.1 nm/min. Source


Chen Y.,Jiangsu Polytechnic University | Chen Y.,Key Laboratory of Polymer Materials | Long R.-W.,Jiangsu Polytechnic University | Chen Z.-G.,Jiangsu Polytechnic University
Zhongguo Youse Jinshu Xuebao/Chinese Journal of Nonferrous Metals | Year: 2010

The SiO2 nanoparticles prepared by the hydrolyzing tetraethylorthosilicate were directly coated with CeO2 by chemical precipitation technique. The as-prepared samples were analyzed with X-ray diffractometry(XRD), transmission electron microscope, X-ray photoelectron spectrometer, dynamic light scatter and Zeta potential analyzer. The thermal oxide film covered silicon wafer was polished by CeO2-coated SiO2 composite abrasives, and the polishing behavior of the novel composite abrasives was characterized by atomic force microscope (AFM). The results indicate that the monodisperse, spherical CeO2-coated SiO2 particles have a particle size of 150-200 nm and are uniformly coated by the CeO2 nanoparticles. The isoelectric point of CeO2-coated SiO2 nanoparticles is about 6.2, which displays a significant shift toward pure CeO2. The shell CeO2 is chemically bounded with SiO2 core, and the Si-O-Ce bond forms between them. The surface roughness within 2 μm×2 μm area of thermal oxide film polished by CeO2-coated SiO2 composite abrasives is 0.281 nm, and the material removal rate reaches 454.6 nm/min. Source


Bai W.,Fujian Normal University | Xiao X.,Fujian Normal University | Chen Q.,Key Laboratory of Polymer Materials | Xu Y.,Fujian Normal University | And 2 more authors.
Progress in Organic Coatings | Year: 2012

By grinding cardanol and anhydrous FeCl 3 powder using a glass pestle in a mortar at ambient and solvent-free condition, a novel cross-linked polymer from cardanol, a renewable resource, was synthesized in high yield up to 80% in 5 min. The products were characterized through UV-vis, FT-IR, and 1H NMR; and the solvent-free grinding polymerization was consisted of Friedel-Crafts reaction, etherification reaction, and oxidative coupling reaction. The effect of these different techniques on spectral, thermal, optical, electrical, and morphological properties of polycardanol were investigated. © 2012 Elsevier B.V. Source


Bai W.,Fujian Normal University | Bai W.,Key Laboratory of Polymer Materials | Lin J.,Fujian Normal University | Lin J.,Key Laboratory of Polymer Materials
Progress in Organic Coatings | Year: 2011

Novel anti-ultraviolet UFP/MPA/SiO2 nanocomposite coatings were prepared from urushiol formaldehyde polymer (UFP) and multihydroxyl polyacrylate resin (MPA) via the sol-gel process. FT-IR spectroscopy was employed to reveal the nanocomposite structure between UFP/MPA and nano-SiO2. TEM was used to observe the size scale and the distribution of nanoparticles throughout the polymer matrix. Simultaneously, the dynamic mechanical properties were characterised through dynamic mechanical thermal analysis (DMTA). The influence of the SiO2 content on the physical mechanical and anticorrosive properties of UFP/MPA/SiO2 nanocomposites was investigated. Moreover, the 1000 h anti-ultraviolet tests showed that the ultraviolet resistance of UFP/MPA/SiO2 coatings improved. The best anti-ultraviolet and anticorrosive properties were achieved when the SiO2 content was 5 wt.%. © 2011 Elsevier B.V. All rights reserved. Source

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