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Polystyrene Composites (polystyrene + composite)
Selected AbstractsOne-Step Ionic-Liquid-Assisted Electrochemical Synthesis of Ionic-Liquid-Functionalized Graphene Sheets Directly from Graphite,ADVANCED FUNCTIONAL MATERIALS, Issue 10 2008Na Liu Abstract Graphite, inexpensive and available in large quantities, unfortunately does not readily exfoliate to yield individual graphene sheets. Here a mild, one-step electrochemical approach for the preparation of ionic-liquid-functionalized graphite sheets with the assistance of an ionic liquid and water is presented. These ionic-liquid-treated graphite sheets can be exfoliated into functionalized graphene nanosheets that can not only be individuated and homogeneously distributed into polar aprotic solvents, but also need not be further deoxidized. Different types of ionic liquids and different ratios of the ionic liquid to water can influence the properties of the graphene nanosheets. Graphene nanosheet/polystyrene composites synthesized by a liquid-phase blend route exhibit a percolation threshold of 0.1 vol % for room temperature electrical conductivity, and, at only 4.19 vol %, this composite has a conductivity of 13.84,S m,1, which is 3,15 times that of polystyrene composites filled with single-walled carbon nanotubes. [source] Thermal and dielectric properties of fiber reinforced polystyrene compositesPOLYMER COMPOSITES, Issue 11 2008Suzhu Yu Thermal and dielectric properties of polymer composites are important for many applications such as microelectronic packaging. In this work, glass fiber, alumina fiber, and carbon fiber reinforced polystyrene composites have been prepared with melt blending. The thermal conductivity, thermal expansion, and dielectric properties of the composites have been systematically studied as a function of fiber fraction. It is found that all the three types of the fibers, particularly the carbon fiber, can significantly increase the thermal conductivity and decrease the thermal expansion of the polymer. Moreover, the incorporation of the glass or alumina fibers does not have obviously adverse effect on the dielectric constant of the polymer. The thermal conductivities of the fibers reinforced composites have also been analyzed with Agari's model to reveal the conductive enhancement nature of the fibers to the polymer. POLYM. COMPOS., 2008. © 2008 Society of Plastics Engineers [source] Influence of Ca[(Li1/3Nb2/3)0.8Ti0.2]O3-, filler on the microwave dielectric properties of polyethylene and polystyrene for microelectronic applicationsPOLYMER ENGINEERING & SCIENCE, Issue 3 2010Sumesh George Ceramic reinforced polyethylene and polystyrene composites were prepared by melt mixing and hot molding techniques. Temperature stable low-loss Ca[(Li1/3Nb2/3)0.8Ti0.2]O3-, (CLNT) ceramic was used as the filler to improve the dielectric properties of the polymers. The relative permittivity and dielectric loss in the microwave frequency range were increased with increase in the ceramic loading. As the filler content increased from 0 to 0.50 volume fraction, the relative permittivity increased from 2.3 to 9 and dielectric loss tangent from 0.0006 to 0.005 for polyethylene-CLNT composite. In the case of polystyrene-CLNT composite, the relative permittivity and dielectric loss tangent increased from 2.1 to 10.5 and 0.0005 to 0.0032 respectively with increase in filler content from 0 to 0.50 volume fractions. The thermal stability of the relative permittivity of polymer ceramic composites was also investigated. The experimentally observed relative permittivity was compared with theoretical models. POLYM. ENG. SCI., 2010. © 2009 Society of Plastics Engineers [source] |