An elastomer is a polymer with the property of elasticity.
The term, which is derived from elastic polymer, is often
used interchangeably with the term rubber, although the latter is
preferred when referring to vulcanisates. Each of the monomers
which link to form the polymer is usually made of carbon,
hydrogen, oxygen and/or silicon. Elastomers are amorphous polymers
existing above their glass transition temperature, so that
considerable segmental motion is possible. At ambient temperature
rubbers are thus relatively soft and deformable. Their primary
uses are for seals, adhesives and molded flexible parts.