Raw Materials—Rubber Dam

Rubbers form a special class of materials characterized by a unique combination of useful properties such as elasticity, flexibility, toughness, and impermeability. The uses of rubbers include both engineering and speciality applications. The properties of rubber products depend not only on the characteristics of rubbers but also on the various additives and ingredients mixed into the basic rubber to form a rubber compound. The selection of additives and their incorporation into the rubber to improve the properties of a raw rubber is based more on experience and art than on a rational or scientific approach. The rubber industry has innovated and achieved a lot over the last few years. Service lives of rubber products have dramatically improved. None of these innovations would have been possible without an emphasis on understanding the chemistry of raw materials and compounds. Generally a tubular composites assembly is divided into an outer layer, middle layer, and an inner layer serving the function of protection, adhesion, and impermeability to the final structure. Modification in engineering aspects, that is, gauge size (thickness), has an influence on the service of the fabricated composites, but as this chapter is dedicated to raw materials for rubber dam, information on raw materials used for achieving specified properties and basic rubber compounding is described.