Of all polymerization methods, catalytic polymerization offers the broadest scope of microstructure control. Stereoregularity, comonomer incorporation and sequences, molecular weights, and molecular weight distributions can be controlled by the catalyst structure. Polyolefins are produced on a vast scale of nearly 100 million tons annually, predominantly by catalytic polymerization. High-densit...

Gas phase polymerization of propylene was carried out in a semi-batch minireactor using a commercially supported Ziegler–Natta (ZN) catalyst. The influence of variables including monomer partial pressure, external electron donor, reaction temperature and time on the particle morphology and size distribution was investigated. Generally, more uniform fragmentation and particle densities were obta...

50 years ago, Karl Ziegler and Giulio Natta were awarded the Nobel Prize for their discovery of the catalytic polymerization of ethylene and propylene using titanium compounds and aluminum-alkyls as co-catalysts. Polyolefins have grown to become one of the biggest of all produced polymers. New metallocene/methylaluminoxane (MAO) catalysts open the possibility to synthesize polymers with highly ...