The other half of the vinyl polymer is based on the natural element chlorine.
Chlorine gives vinyl two advantages.
Thus, vinyl is less sensitive to fluctuations in the world oil market than are totally oil dependent polymers. Second, chlorine has excellent inherent flame retardant properties. These properties are passed on directly to vinyl end-products, making vinyl an excellent choice for applications such as electrical conduit and wiring that require high resistance to ignition and flame spread. This versatility is yet another reason why vinyl claims such a large share of the plastics market. It is the only plastic that can be made thin and flexible enough for wallcoverings, yet rigid and tough enough for siding on buildings.