Room temperature vulcanizing (RTV) silicone sealants are discussed in-terms of the curing chemistry and the relation of the chemistry to the physical properties. Individual properties such as adhesion and modulus characteristics and their relations to overall sealant performance are also discussed. The paper describes a new group of silicone sealants having properties such as high strength, “knotty tear,” primerless adhesion, noncorrosiveness to copper, flame retardancy, and low modulus; pressure-sensitive adhesives are also discussed. These newly developed properties, coupled with the excellent performance characteristics of silicones and the ideal handling properties of RTV sealants, account for the increasing utilization of silicones in applications once served exclusively by organic sealants.
