EPDM is the designation given for a saturated polymer chain of the polymethylene type, consisting of ethylene, propylene, and diene. It has been and continues to be one of the most widely used and rapidly growing synthetic rubbers. Technology development has been driven by novel catalysts and processes that have expanded the range of products while delivering improvements in manufacturing such as energy efficiency and environmental footprint. A broad overview of the EPDM process and product technology is presented with focus on more recent developments. The range of topics includes polymer chemistry and physics, characterization, applications, and the manufacturing process. Technology platforms based on both the Ziegler–Natta catalysts and metallocene catalysts are compared and contrasted.

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Hall measurements and four‐point probe resistivity measurements were used to determine the concentration profile of boron in doped semiconductor silicon ingots grown by Czochralski and Bridgman techniques. The concentration profiles were fitted to the normal segregation equation and the effective segregation coefficient, knormaleff , was calculated. The average value of knormaleff for boron was 0.786±0.036 in Czochralski single crystals and 0.803±0.036 in Bridgman polycrystals.

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Durch Reduktion von SiO2 mit Kohle im 100 kW Lichtbogenofen dargestelltes Si besitzt eine B‐Verunreinigung von 1.8 ppma.