Demystifying Ziegler–Natta Catalysts: The Origin of Stereoselectivity

Industrial Ziegler-​Natta catalysts for polypropylene prodn. are complex formulations with a reputation of 'black boxes'. In the present paper, we report the results of an extensive study of the three latest generations with com. relevance, carried out with advanced High Throughput Experimentation tools and methods. The thus-​obtained database of structure​/properties relationships, of extraordinary width and depth, provided a high-​definition picture of the screened systems, enabling us to highlight important details of their inner workings. In particular, the delicate relation between surface coverage and lateral steric pressure on the catalytic species, and the impact of chemisorbed donor and Al-​alkyl species on said parameters for different formulations, were elucidated.