Fabrication and Characterization of PVA/PEO/CB Nanocomposite Films

In this paper, we report the fabrication of polyvinyl alcohol (PVA) and polyethylene oxide (PEO) blended polymer nanocomposite (PNC) films loaded with different percentages of carbon black (CB) using the stencil printing method. The effect of the PEO-PVA blend weight ratio on the existence of the dual-phase was studied. The fabricated films were characterized using the high-resolution scanning electron microscope (HRSEM), the surface profilometer, and the four-point probe resistive measurements. HRSEM analysis showed the homogenous dispersion of carbon black fillers in the polymer blend matrix. It has also revealed the formation of carbon black agglomerations in the polymer matrix. The topographical properties of the films such as the surface roughness and thickness were obtained. The CB concentration in the polymer blend had been varied from 0 to 14wt%. A typical PNC film loaded with 14wt% CB had a thickness of 120 ± 0.24 µm. The I-V characteristics of the PNC films were obtained to investigate the effect of thickness and CB content variation. An electrical conductivity of 0.417 S/m was achieved with 14wt% CB loading. The percolation threshold and critical exponent of the PNC films was estimated to be 0.2 vol% and 1, respectively. The latter indicated the presence of a two-dimensional conductive network. In general, the CB-polymer composite films with improved structural and electrical properties were fabricated and characterized for potential sensor applications.