POLYMERs
Polymers include the familiar plastic and rubber materials. Many of them are organic compounds that are
chemically based on carbon, hydrogen, and other nonmetallic elements (O,N, and Si).
Furthermore, they have very large molecular structures, often chain-like in nature that have a backbone of
carbon atoms.
These materials typically have low densities, whereas their mechanical characteristics are generally dissimilar
to the metallic and ceramic materials—they are not as stiff nor as strong as these other material but more
ductile to deform.
In general, they are relatively inert chemically and unreactive in a large number of environments. One major
drawback to the polymers is their tendency to soften and/or decompose at modest temperatures,
which, in some instances, limits their use. Furthermore, they have low electrical conductivities and are
nonmagnetic.