Chemical resistance

Many plastics have the ability to withstand attack of acids, alkalis, solvents, and other chemicals. Generally plastics have good chemical resistance. Part of the wide acceptance of plastics is from their relative compatibility to chemicals, particularly to moisture, as compared to that of other materials. Because plastics are largely immune to the electrochemical corrosion to which metals are susceptible, they can frequendy be used profitably to contain water and corrosive chemicals that would attack metals. Plastics are often used in applications such as chemical tanks, water treatment plants, and piping to handle drainage, sewage, and water supply.

Structural shapes for use under chemical and corrosive conditions often take advantage of the properties of glass fiber-thermoset RPs. Today's RP (not steel tanks) gasoline underground tanks must last thirty or more years without undue maintenance. To meet these criteria they must be able to maintain their structural integrity and resist the corrosive effects of soil and gasoline including gasoline that has been contaminated with moisture and soil.

Some plastics like HDPE are immune to almost all commonly found solvents. PTFE (polytetrafluoroethylene) in particular is noted principally for its resistance to practically all-chemical substances. It includes what has been generally identified as the most inert material known worldwide.

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