Published: April 1980
Commercial production of polypropylene is based on the use of Ziegler-Natta type coordination catalysts. Polymerization is carried out In either the liquid phase with polymer forming as a slurry of particles, or the gas phase with polymer forming dry solid particles. Current process development is strongly orientated toward improving catalyst productivity and stereospecificity to make it unnecessary to remove catalyst residues and atactic polymer from the product.
In this report, the new high-productivity-catalyst processes of Miteui Petrochemlcal/Montedison and of Solvay are evaluated. Their economics are compared with updated economics of the Dart and BASE' processes evaluated in previous PEP Reports (Nos. 19A and B).
The production of both homopolymer and of ethylene-propylene block copolymer is considered for the Mitsui P.C./Montedison and Solvay processes.