Weathering static exposures

Ethylene-acrylic elastomers are highly resistant to the damaging aspects of weather, ie, sun, water, oxygen, and ozone. Vulcanizates have shown little change in tensile properties and no visible signs of surface deterioration after exposure to the elements in Florida for 10 years. Samples imder 20% tensile strain (static) displayed no cracks after one week s exposnre to 100 ppm ozone in air, a concentration 100 times greater than is usually specified in qualifying tests. 

Keywords Reciprocity UV intensity Weathering Acceleration Correlation ORWET Polystyrene Irradiance Temperature Ultra-Accelerated Weathering System UA EMMA Exposure Exhapolation ASTM G90 Color Outdoor Static Dynamic Hypervolume... 

Low Movement Seaiants (Caulks). These include polybutene, polyisobutene, and oil and resin-based caulks. These low cost sealants have an approximate joint movement capacity of only 5%, a slow rate of cure (120 days), a low Shore A hardness, a relatively short service life (approximately 6 or 7 years on average), and only modest weather or chemical resistance. Therefore, low movement sealants are primarily utilized in static joints having minimal exterior exposure. 

Brennan, P Fedor, G., and Pausch, G.. Static and Rotating Xenon Arc Exposures Compared, 1 European weathering Symposium, Proceedings of the XXIII Colloquium of Danubian Countries on natural and Artificial Aging of Polymers, Prague, Sept. 2003. 

---