Abstract: Mixing vinyl-containing polydiorganosiloxane, an organosilicon compound containing silicon-bonded hydrogen atoms, a platinum catalyst, and an amidosiloxane provides a composition which exhibits improved adhesion to many substrates without the use of a primer when heat cured in contact with the substrate. An example of the amidosiloxane is ##STR1## The compositions have self-adhering properties and also exhibit an extended pot life. The compositions can be prepared by mixing the polydiorganosiloxane, platinum catalyst, and amidosiloxane into one package of a two package product and the organosilicon compound forms the other package. The two packages are mixed before use to form a curable product.

Abstract: Mixing vinyl-containing polyorganosiloxane, a silicon-bonded hydrogen containing organosilicon compound, a platinum catalyst, a polysiloxane having at least one silicon-bonded vinyl radical and at least one silicon-bonded hydroxyl radical and an epoxy-containing, alkoxy silane provides a composition which exhibits improved adhesion to many substrates without the aid of a primer when heat cured in contact with the substrate. An example of the polysiloxane is a hydroxyl endblocked polymethylvinylsiloxane and an example of the epoxy silane is ##STR1## The compositions not only have self-adhering properties but also exhibit an extended pot life. The compositions can be prepared by mixing the polysiloxane and epoxy silane at room temperature and thereafter adding the mixture to the other ingredients. The remaining ingredients can be in the form of a two package product in which the polysiloxane-epoxy mixture is added to one package before the packages are mixed to form a curable product.

Abstract: Organopolysiloxane compositions suitable for use in a liquid injection molding process of elastomeric articles are produced by mixing a vinyl-endblocked polydiorganosiloxane fluid copolymer containing dimethylsiloxane units and methyl-3,3,3-trifluoropropylsiloxane units, a treated, reinforcing silica filler, a platinum-containing catalyst, a curing agent comprising dimethylhydrogensiloxane units as the only source of silicon-bonded hydrogen atoms and, as an inhibitor for the platinum-containing catalyst, certain olefinic siloxanes and/or acetylenic siloxanes. These compositions are especially suited for liquid injection molding because they can be stored at room temperature for days and can be injected into a hot mold with pressures less than 352 kg./sq.cm. (5,000 psi) whereon they cure rapidly to an elastomeric article having a tensile strength greater than 42 kg./sq.cm., and elongation at break greater than 300 percent and a tear strength greater than 7 kg./cm.