US Patent 7799243 Shape memory main-chain smectic-C elastomers

Shape memory main-chain smectic-C elastomers are described, as are methods for their preparation and monomers used in such methods. The elastomers are prepared by hydrosilylation of a reaction mixture including a liquid crystalline diene, a crosslinking agent, and a bis(silyl hydride) compound. The elastomers exhibit shape-memory properties and spontaneously reversible shape changes. They are useful for fabrication of shape memory articles including, for example, implantable medical devices, contact lenses, reversible embossing media, and Fresnel lenses.