The following checklist provides several characteristics that should be considered when specifying an elastomeric compound. In addition to knowing which physical, mechanical, and chemical resistance properties are required, it is important to know that a material is compounded and tested to meet any necessary industrial specifications, such as UL, ASTM, SAE, FDA, NSF International, and U.S. Military Standards. The following are brief summaries of the properties of seven of the most versatile polymers. While the list is not exhaustive, a majority of sealing, gasketing, and weather stripping needs can be met using these popular materials.
Silicone features excellence resistance to ozone, sunlight, and oxidation, and is very color stable.
It also maintains excellent flexibility at low temperatures, has outstanding resistance to high heat, has low compression set, and is a very good electrical insulator. However, it is not recommended for applications that require abrasion resistance, tear and cut-growth resistance, and high tensile strength. Nor is it recommended for resistance to oil, gasoline, solvents, alkalis, and acids. It is not recommended for resistance to oil, gasoline, and hydrocarbon solvents. EPDM is found in a wide range of applications and is good for outdoor use.