This article reviews the surface science of the heterogeneous olefin polymerization catalysts. The specific focus is on how to prepare and characterize stereochemically specific heterogeneous model catalysts for the Ziegler-Natta polymerization. Under clean, ultra-high vacuum conditions, low-energy electron irradiation during the chemical vapor deposition of model Ziegler-Natta catalysts can be...

A novel imido-modified SiO2-supported Ti/Mg Ziegler-Natta catalyst for ethylene and ethylene/1-hexene polymerization is investigated. The catalyst is prepared by modification of (SiO2/MgO/MgCl2)TiClx Ziegler-Natta catalysts via supporting vanadium species followed by reaction with p-tolyl isocyanate as imido agents, to get the merits from both the SiO2-supported imido vanadium catalyst and the ...

In a survey based on the biographical sketches, obituary notes and eulogies of notable scientists, eight were identified as belonging to an elite group, having authored more than 1000 research publications, which include books, monographs and patents. They were, in chronological order, Thomas Alva Edison, Paul Karrer, Margaret Mead, Giulio Natta, Hans Selye, Herbert C Brown, Tetsuji Kametani an...

We examine the recent data and analysis of Natta et al. concerning the accretion rate on to young stars as a function of stellar mass, and conclude that the apparently steep dependence of accretion rate on mass is strongly driven by selection/detection thresholds. We argue that a convincing demonstration of a physical relationship between accretion and stellar mass requires further studies whic...

Modeling and Simulation of an Emulsion Copolymerization Process Sabrina Copelli*, Mario Dente, Marco Derudi, Giulia Bozzano, Vincenzo Torretta Università degli Studi dell’Insubria Dip. di Scienza e Alta Tecnologia Via G.B. Vico 46 21100 Varese Italy b Politecnico di Milano Dip. di Chimica, Materiali e Ingegneria Chimica “G. Natta”P.za Leonardo da Vinci 20133 Milano Italy sabrina.copelli@uninsub...