Mechanical properties of triple composites of polycarbonate, single-walled carbon nanotubes and carbon fibres

The present work was undertaken to study the mechanical properties of reinforced polycarbonate systems, where the filler material consists of single-walled carbon nanotubes (SWCNTs), of carbon fibres (CF) or of both. The SWCNTs were taken from different sources, laser ablation and arc discharge, and carefully characterized before their incorporation into the matrix system. The loadings of the reinforcement material were varied from 1 to 35.5 wt% in the thermoplastic polymer. All composites were produced by melt extrusion. Experimental results show that small amounts of carbon nanotubes randomly distributed in thermoplastic matrix systems do not inevitably enhance the mechanical stability. Higher mechanical improvements could be attained by adding CF to the composite system. A triple composite of polycarbonate, PC/SWCNTs/CF reveals synergy effects in mechanical and electrical aspects. The composites were investigated by stress–strain measurements, dynamical mechanical analysis and hardness probing.