Negative thermal coefficient behaviour, dielectric and mechanical properties of poly(vinyl chloride)/poly(vinyl alcohol) blends

Polyvinyl alcohol (PVA) in polyvinyl chloride (PVC) blends were prepared by using extrusion molding technique in various weight percentages. The prepared blends were characterized by FTIR and SEM for structural and surface morphology study. Further, the DC conductivity was studied by two probe method and found that the 6% of PVC-PVA blends shows high conductivity of 8.34×10−7 S cm−1. This increase in conductivity may be due to the extended chain length of blends, which is confirmed by the negative thermal coefficient graphs. The AC conductivity of blends increases with increase in applied frequency. Among all blends, 6 wt % shows high conductivity of 2.59×10−6 S cm−1 and low tangent loss of 0.9 Ω. The PVC with PVA blends enhances the mechanical strength and modulus property as the percentage of elongation increases up to ~660, hence these polymer blends can be used in many applications like solar cells and gas sensor encapsulation device, low k-dielectric materials, food packing and other electronic devices.