A combination of materials that may be formed through an extrusion process. The resulting product has at least two layers. By coextruding multiple layers of at least two types of materials together, the final product may have improved mechanical, thermal, electrical, and other properties as compared to the original materials used. Additionally, by using an additive, filler, or doping material in at least one layer of the final product during the extrusion process, the mechanical, thermal, electrical, or other properties of the final product may be further improved.