Sulfur blocks, molded

Terrel, et al (33,3A 35). Another approach uses SC to fabricate various block shapes and is aimed at a variety of uses particularly suited for the Middle East. Until recently, all attempts to develop a cold, press-mold sulfur-based technology have been unsuccessful. However, this barrier appears to have been broken with the promising technology being developed at the University of Washington, Seattle. Through careful formulation,... 

The materials selected for evaluation included three materials currently being used in these applications Biomer (Thoratec Laboratories Corporation, Emeryville, CA), representative of segmented ether-type polyurethanes Avcothane-51 (Avco Everett Research Laboratory, Inc., Everett, MA), a block copolymer of 10% silicone rubber and 90% polyurethane and Hexsyn (Goodyear Tire and Rubber Company, Akron, OH), a sulfur vulcanized hydrocarbon rubber that is essentially a polyhexene. Also selected, because of their easy availability, were Pellethane (Upjohn Company, North Haven, CT), an ether-type of polyurethane capable of being extruded in sheet form, and a butyl rubber formulation, compounded and molded at the National Bureau of Standards. The material thickness varied, but the sheets were generally about 1 mm thick. 

When molten pig iron is poured into molds of a desired shape (engine blocks, brake drums, transmission housings), it is called cast iron. However, pig iron and cast iron contain too much carbon and other impurities for most uses. The structurally stronger material known as steel is obtained by removing the phosphorus, sulfur, and silicon impurities and decreasing the carbon content. 

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