Effects of size and shape originated synergism of carbon nano fillers on the electrical and mechanical properties of conductive polymer composites

Abstract

In this study, microstructural features, mechanical properties, and electrical conductivity behaviors of thermoplastic composites prepared by using of cyclic olefin copolymer (COC) as matrix and various types of carbon nano materials, expanded graphite (EG), carbon nanofiber (CNF), and multi walled carbon nanotubes (CNT) as conductive fillers were investigated. Effects of using of double and triple filler combinations on the electrical properties of composites were also quantified in detail by measuring the bulk resistance of samples under alternating current with an impedance spectrometer. The electrical percolation values of fillers were found to be 20, 10, and 5 phr for the series of composites prepared with the EG, CNF, and CNT, respectively. It was obtained that the bulk resistances of percolated samples were dramatically decreased from 10 14 ohm.cm to 10 3 210 4 ohm.cm. On the other hand, it was also found that the using of double and triple filler combinations provided much lower (about 10 1 ohm.cm) bulk resistance which corresponded to higher conductivity values than the highly filled composites including of 30 and 40 phr of EG. Based on the DMA measurements and the quantifying of elastic modulus values of composites in the rubbery region, it was found that the reinforcing effects of carbon nano fillers on the elastic modulus of composites decreased in the order of CNT>CNF>EG, depending on the aspect ratio (A f ) values of fillers into the matrix.

Role of boron mineral size on thermal, microstructural and mechanical characteristic of IPP

“…Virgin IPP depicted the great extension during cold drawing while all IPP based composites failed at the strain softening regions. As seen in figure, the percent elongation of the IPP based composites containing both size of ulexites decreased with the increasing of the ulexite content in the polymer matrix, which resulted that the composite sample gradually gained brittle nature with ulexite content because the polymer matrices had considerably lower stiffness than rigid inorganic ulexite particles [47]. This presumably was caused from that the rigid properties of the ulexites presenting in the IPP matrix limited or prevented the free movements of IPP chains [48].…”

Influence of Nanoparticles on Thermal and Electrical Conductivity of Composites

“…The conductive pathways formed by the nanoparticles absorb the EM radiation and dissipate the resulting stress throughout the matrix [20]. Carbon nanotubes are excellent for providing linear contacts; however, the synergic effect is increased when combining with 1-D nanostructures such as carbon black of graphene oxide nanoparticles [21]. PEDOT:PSS is a core-shell structured conductive polymer with a high degree of mechanical flexibility and excellent dispersion in water [22].…”

Desarrollo y optimización de mezclas de alto rendimiento medioambiental basadas en poliolefinas y cargas de origen natural

“…Un ejemplo de ellos es el valor de E' obtenido para -150 ºC en el BioHDPE es de 2658 MPa mientras que con para la formulación con un 20 % en peso de piña se alcanza un valor de 2886 MPa. Un comportamiento similar ha sido obtenido por parte de diferentes autores tras incorporar diferentes subproductos de tipo lignocelulósico en diferentes matrices poliméricas [173,174].…”