Abstract: The invention relates to a delivery device for the controlled release of the therapeutically active agent gestodene, over a prolonged period of time, at a release rate of 0,1-300 &mgr;g/day, said device comprising a core comprising at least said therapeutically active agent, and a membrane encasing said core wherein said membrane is made of an elastomer. According to the invention, the elastomer is a siloxane-based elastomer comprising 3,3,3-trifluoropropyl groups attached to the Si-atoms of the siloxane units, and the release rate of said therapeutically active agent of said delivery device is regulated by the amount of said 3,3,3-trifluoropropyl groups.

Abstract: The invention relates to a delivery device for the controlled release of a therapeutically active agent, especially an androgen, over a prolonged period of time, said device including a core containing the therapeutically active agent, and a membrane encasing the core wherein the membrane is made of an elastomer. According to the invention, the elastomer is a siloxane-based elastomer which includes 3,3,3-trifluoropropyl groups attached to the Si-atoms of the siloxane units.

Abstract: The invention relates to a delivery device for the controlled release of a therapeutically active agent, especially a progestin or an estrogen, over a prolonged period of time, said device including a core which contains the therapeutically active agent, and a membrane encasing the core wherein said membrane is made of an elastomer. According to the invention, the elastomer is a siloxane-based elastomer which includes 3,3,3-trifluoropropyl groups attached to the Si-atoms of the siloxane units.

Abstract: The invention relates to a siloxane-based elastomer intended for controlling the permeation of drugs, wherein the elastomer includes 3,3,3,-trifluoropropyl groups attached to the Si-atoms of the siloxane units.The invention relates also to a method for the preparation of a siloxane-based elastomer including 3,3,3,-trifluoropropyl substituents, where the elastomer is intended for controlling the permeation of drugs.In the method eitheri) a 3,3,3,-trifluoropropyl-substituted vinyl-functional polysiloxane component and a silicon hydride-functional crosslinking agent are crosslinked in the presence of a catalyst, orii) a 3,3,3,-trifluoropropyl-substituted polysiloxane component is crosslinked in the presence of a peroxide catalyst.

Abstract: A thermoplastic elastomer is achieved by absorbing an acrylate monomer, an initiator and eventually a diacrylate into polyolefin particles, after which the temperature is raised and the acrylate polymerises into the polyolefin and forms a dispersed phase, which has been functionalized by copolymerising a functional monomer together with the acrylate. As a compatibiliser a grafter polyolefin is used, which is melt-blended after the polymerisation into the thermoplastic elastomer or before the polymerisation into the polyolefin.