Plastic valves are made from plastic materials and are used in applications that require corrosion resistance and/or chemical handling. They are made from acetal polymers, polyvinyl chloride (PVC), chlorinated PVC (CPVC), polytetrafluoroethylene (PTFE), polyethylene (PE), polypropylene (PP), and polyvinylidene fluoride (PVDF). Acetal polymers offer excellent lubricity, fatigue resistance, and chemical resistance. PVC provides good flexibility, smooth surfaces, and nontoxic qualities. CPVC is suitable for high temperature applications and is used in hot water distribution. PTFE exhibits a high degree of chemical resistance and a low coefficient of friction. PE is a soft, flexible and tough plastic with outstanding electrical properties but poor temperature resistance. It is prone to stress cracking and has poor resistance to ultraviolet (UV) light. PP is similar to PVC, but can be used in exposed applications because of its resistance to UV, weathering and ozone. PVDF has good wear resistance and excellent chemical resistance, but does not perform well at elevated temperatures.