The use of fillers in both thermoplastic and thermoset polymers has been common. The practice of filling polymers is motivated both by cost reduction and by the need to obtain altered or enhanced properties. Nanostructured dielectric materials have demonstrated advantages over micro-filled polymer dielectrics. However, this is a need to improve these nanocomposites such that they can be adapted for use in such situations as electrical insulation for low or medium voltage cables. This invention is directed to a nanocomposite material that is adapted for electrical insulation including a polymer having compounded therein a substantially homogeneously distributed functionalized dielectric nanoparticle filler. The nanocomposite material is suitable for the formulation of electrical insulation, such as power cables, cable accessories, and the like, for highlowmedium AC voltage and high DC voltage.