Plastic Centrifugal Pumps. These centrifugal pumps are designed for use with corrosive, toxic, noxious, radio-active, and carcinogenic liquids. The pump fluid chamber is isolated from the separate external motor which drives the pump. Magnetic drives act as a link between the shaft and impeller. Similar to mag-drive pumps, except they are made from polypropylene, polyvinylidene fluoride, or similar materials.