Certainly, the mechanical properties of gaskets and o-rings are defined by their application. Their use is more often associated with engines for such industries as the automotive, aerospace, marine, and agricultural, but sealants are also in machinery used in factories, plants, and manufacturing centers. In all likelihood, anywhere that an engine or machine is in operation it is sealed with a low or high-temperature sealant that must have the mechanical properties necessary to perform effectively in extreme environments.
Materials for seals are derived from rubber, or more precisely, elastomers, a synthetic elastic polymer. A polymer can be cured to enhance mechanical properties specific to its performance. Mechanical properties may include a need for flexibility, absorption, tensile strength, and resistance to tears, corrosive environments, or the ability to withstand extreme heat or cold. For example, elastomeric material for a high-temperature o-ring might be designed to function in an application subjected to corrosion and extreme heat, or designed for a low temperature, tear-resistant application. In each case, the engineers must know how the mechanical properties of the seal will respond to a reaction force, i.e., the temperature and how it will affect the seal in order to ensure the integrity of the component.