New viscoelastic composite materials that simultaneously combine high stiffness and high loss

The stiffness modulus and loss tangent are usually mutually exclusive properties so it is a technological challenge to develop materials that simultaneously combine high stiffness and high loss. Here, inspired by our recent finite element numerical predictions, we achieve this unusual balance of properties by filling a solid polymer matrix with rigid inorganic spheres coated by a sub-micron layer of a viscoelastic material with a high level of internal friction.