Parts to be made of Teflon® may be designed in exactly the
same manner as parts made of other materials, such as
steel, brass, lead, concrete, etc. Even the same formulas
may be used if careful attention is paid to special
characteristics of the resin. A Teflon® resin may be chosen
in preference to other materials because of its better
chemical resistance, heat resistance, friction coefficient,
dielectric strength, toughness, weather resistance, or
combination of such properties. Most materials are affected
to some extent by temperature, moisture, and environment.
Because Teflon® resins exhibit zero moisture absorption
and are unaffected by almost all environmental conditions,
designers will be interested mainly in property changes
resulting from temperature variation.