Preparation And Electrical Conductivity Of Polyether Ether Ketone/Carbon Nanotube Composite

The composite of PEEK/CNT was fabricated by hot-pressing the mixture of PEEK/CNT which was prepared by evaporating the mixture of CNT suspension and PEEK particle suspension. The successful delivery of CNT electrical conductance to the insulating PEEK matrix was achieved, and the factors influencing electrical conductivity was studied. The critical concentration of this system is around 3 wt.%, which is lower than those acquired by the simple melt blending method. This is due to the excluded volume effect available for the hot-pressed composite. The reisistivity of composite with 5 wt.% loading is 104.7?·cm, as the resisitivity of PEEK is > 1015?·cm.The dispersion of CNTs was achieved by the ultrasonication and the use of dispersant SDS. With low-power ultrasonication, low concentration of SDS would optimize the conductivity of PEEK/CNT composite. However, with high-power ultrasonication, the presence of SDS was detrimental to the conductivity of PEEK/CNT composite. This could probably be attributed to the combination of dynamic mixing of CNTs and PEEK particles and the CNTs being tangled but loose reflected by TEM characterization. In addition, the fact that the conductivity of composite increases with the ultrasonication time in studied range also confirmed this assumption. The electrical conductivity increases with the PEEK particle size because of the fact that the exluded volume gains as the deformability of PEEK particle during the hot-pressing. The SEM micrographs of PEEK/CNT mixture powder and fracture surface of PEEK/CNT composite visualize the dispersion state of CNTs on PEEK particles and throughout the PEEK matrix respectively, and help the understanding of conducting network formation of CNTs in the matrix. Furthermore, we proposed the uniformity coefficient based on the electrical conductivity of CNT/polymer to evaluate the uniforimity of CNTs throughout the PEEK matrix. And the UC of this composite system is low (1/6) due to the combination of high critical concentration and good dispersion of CNTs on the surfaces of PEEK particles.Finally, the composite of PEEK/CNT was achieved, but there are studies left for this type of composites, including the research of mechanical properties, crystallinity influenced by the presence of CNTs and further melt blending of PEEK/CNT mixture.