Abstract: The invention is directed to swellable seals and their use. In accordance with the invention there is provided an elastomeric seal for sealing bore holes and the like comprising a fluid-swellable elastomer composition, which comprises an elastomer matrix, at least one fluid-soluble compound and at least one type of fiber.

Abstract: The invention is directed to elastomeric polymer materials having controllable swellable properties and to the use of such materials. The invention provides an elastomer composition that comprises an elastomer matrix and a precursor for a swellable compound, which precursor has limited solubility in a fluid such as water and which may be converted into a compound that is soluble in said fluid such as water. The compositions of the invention may be used in a process that comprises bringing the composition to a desired location and converting said precursor into a fluid-soluble compound, while allowing said composition to be in contact with said fluid, prior to, during and/or after said converting of said precursor.