Karl Ziegler. Portrait of the German chemist and Nobel Laureate, Karl Ziegler (1898-1973). Ziegler became director of the Kaiser Wilhelm Institute for Coal Research in 1943. There he showed how polymerization occurred and discovered catalysts that polymerized the reaction of ethene molecules to form polythene (polyethylene). He later found catalysts that formed this plastic polymer at room temperature and atmospheric pressure. Ziegler shared the Nobel Prize for Chemistry with Giulio Natta in 1963 for this work.