High energy density capacitors and compounds for use in their preparation

The present invention relates to high energy density capacitors and the dielectric materials used therein. It particularly relates to dielectric materials of polymerized (alpha-substituted)acrylate monomers or use in a thin film capacitor, such as a polymer multilayer capacitor. A high energy density capacitor comprising an organic polymeric dielectric material having a dielectric constant of at least about 7; wherein the organic polymeric dielectric material comprises polymerized alkyl (alpha-substituted)acrylate monomers having at least one dipole group; wherein when the monomers are polymerized, the dipole group is attached to the main polymeric chain through a heteroatom-containing linking group.