Ziegler, << TSEE gluhr, >> Karl (1898-1973), a German scientist, improved methods of producing plastics that resulted in many of the materials that revolutionized life in the 1900’s. Italian chemist Giulio Natta further developed Ziegler’s processes, and they were jointly awarded the Nobel Prize for chemistry in 1963 (see Natta, Giulio ).
Ziegler was born in Helsa, Germany, and received his Ph.D. from the University of Marburg. After numerous academic appointments he became head of the Kaiser Wilhelm Institute (now the Max Planck Institute) for Coal Research at Mulheim. He remained there until his retirement in 1969. In the mid-1900’s, Ziegler made his most important contribution–the discovery of the process of polymerization. He was studying reactions involving the gas ethylene (see Ethylene ). By chance, a trace of nickel was left in his apparatus from previous experiments. Ziegler found that the ethylene molecules were joined together to form a longer chain of carbon atoms. This chaining together of simpler molecules to form longer ones is called polymerization, and the product is a polymer. Plastics and rubber are examples of polymers. Ziegler found that certain compounds containing carbon and metal–especially aluminum–catalyzed (promoted) the polymerization of ethylene at atmospheric pressure and a little above room temperature. Previous polymerization processes required high pressures and temperatures, and the molecules produced could be branched or irregularly shaped in other ways. The polymers produced by Ziegler’s new process had a regular structure, and they were more rigid and less easily melted than the polymers produced by older methods. Ziegler’s process became the basis of polymer manufacture for numerous products.
