Born: 26 November 1898, Helsa, Germany
Died: 12 August 1973, Mülheim, West Germany (now Germany)
Affiliation at the time of the award: Max-Planck-Institut für Kohlenforschung (Max-Planck-Institute for Carbon Research), Mülheim/Ruhr, Federal Republic of Germany
Prize motivation: "for their discoveries in the field of the chemistry and technology of high polymers"
Field: industrial chemistry, polymer chemistry
Prize share: 1/2
Synthetic materials like plastics are common in today's world. Plastic consists of very large molecules comprised of long chains of smaller molecules. In 1953 Karl Ziegler developed a method for creating these molecular chains using aluminum compounds as catalysts, which sped up the reaction without forming part of the end-products. The aluminum's electrons are grouped so that active molecules are drawn to them and wedge themselves in between the molecular chain and the aluminum atom. Thus, the chain is lengthened step by step.