GETTING A CHARGE OUT OF PLASTICS

Static-charge buildup can be a serious problem for plastic parts, causing sparking and surface-dust pickup. But new families of plastics have been specifically designed for electrical conductivity. They combine the traditional low-cost flexibility in design of plastic parts with the ability to dissipate static charges. The charge-dissipation process, which involves ion migration from surface to surface, or surface to air, is extremely slow in nonconductive plastics. To speed up the process, conductive fillers such as carbon-black powder, carbon fibers, and metallic fibers are incorporated.