Environmentally compatible polymerization of olefins by the use of metallocene catalysts

Polyolefins belong to the most non-polluting mass polymers since they consist of carbon and hydrogen, only. Additionally the pure polymers can be easily reused, they can be decomposed into their monomer building blocks or they can be burned to carbon dioxide and water under production of energy. With metallocene catalysts the efficiency of the polymerization compared to the common "Ziegler-Natta" catalysts can be increased by the factor of 10-100. Therefore, resources are saved and energy costs decreased. The metallocene catalysts allow in a so far unknown fashion the synthesis of polymers in a very distinctive way. By variation of the ligand structure it is possible to influence as well the microstructure of the polymers as the stereo- and regio-selectivity and the tacticity in a broad range. Therefore, the production of polymers with outstanding mechanical properties becomes possible, so far these were reserved for highperformance polymers, which can be only made with high efforts and less environmentally compatible. (C) 2001 Elsevier Science Ltd. All rights reserved.