Solid-state NMR studies of Ziegler–Natta and metallocene catalysts

Abstract

Ziegler–Natta catalysts are the workhorses of polyolefin production. However, although they have been used and intensively studied for half a century, there is still no comprehensive picture of their mechanistic operation. New techniques are needed to gain more insight in these catalysts. Solid-state NMR has reached a high level of sophistication over the last few decades and holds great promise for providing a deeper insight in Ziegler–Natta catalysis. This review outlines the possibilities for solid-state NMR to characterize the different components and interactions in Ziegler–Natta and metallocene catalysts. An overview is given of some of the expected mechanisms and the resulting polymer microstructure and other characteristics. In the second part of this review we present studies that have used solid-state NMR to investigate the composition of Ziegler–Natta and metallocene catalysts or the interactions between their components.