About two years ago, Stockwell Elastomerics’ Applications Engineering team began a sun, weather, and age test of 37 different gasket materials attached to a board and placed on the roof of the main office building. (View the blog post about the start of that test and the post about the results after one year.) The materials endured temperatures ranging from below freezing to over 100°F, high winds, and precipitation including rain, snow, and sleet.
The experiment tested samples of advanced materials such as silicone sponge, silicone foam, solid silicone, fluorosilicone and PORON® microcellular urethane foam, along with other polymers such as neoprene (polychloroprene), EPDM (ethylene propylene di-monomer), ECH (epichlorohydrin) and SBR (styrene-butadiene rubber).
Here is how the materials are compare after two years of exposure to the environment.
Some of the materials performed far better than others when subject to the same conditions. Silicone materials, such as HT-6240 and R10470M, saw much less deterioration from UV exposure and weather than polyurethane foams like Poron. The neoprene and blended sponges, such as 4119-N and 4022 OCS, fared the worst as they were lost or destroyed over the course of the test. The graphic below demonstrates how each material held up after two years of exposure to the environment.
This experiment helps demonstrate how long term exposure to the UV, weather, and varying temperatures affect different gasket materials. The materials have performed as expected. Silicone has excellent resistance to aging, UV, ozone, and temperature extremes, and therefore survived much longer than the urethane foams and blended materials. Urethane foams such as Poron have great compression set and shock absorbing properties that make them excellent for indoor applications but endure severe cracking and embrittlement when exposed to the elements for prolonged periods of time. It is important to consider all of these factors during material selection to ensure the long term success of the gasket.
Stockwell Elastomerics’ Applications Engineers often provide engineering technical tips to customers that consider exposure to weather, sun and temperature extremes, based on their knowledge and experience about these gasket materials. Contact Stockwell Elastomerics for further assistance.