Abstract: A method for manufacturing filler materials for minerally bonded structural elements with thermal treatment of the starting materials to be used as filler materials involves subjecting comminuted high-polymer materials comprised of natural or synthetic origin materials to a shock-like heat radiation treatment by passing the materials under an irradiation unit to provide a temperature gradient of at least 20K per mm of travel distance of the materials beneath the irradiation unit in which an iron temperature of more than 600.degree. C. can be measured whereby the materials are inertized and are activated by heat in the range of a molar energy of 60 to 170 kJ*mol.sup.-1 and then placing the resulting activated materials in a crystal-forming solution of inorganic substances that enter into a permanently adhesive bond with a basic matrix of a composite material to be formed therefrom.