GAS-PHASE ETHYLENE POLYMERIZATION - PRODUCTION PROCESSES, POLYMER PROPERTIES, AND REACTOR MODELING

A review of relevant macroscopic and microscopic processes of gas phas e ethylene polymerization, both chemical and physical, is given. The c ommercial technology development of gas-phase ethylene polymerization processes is illustrated through a selective survey of the patent lite rature. Both advantages and disadvantages of gas phase polymerization processes are addressed, and the challenges of laboratory studies of g as phase polymerization are also outlined. Physicochemical phenomena o f ethylene polymerization using heterogeneous catalysts are discussed, including examination of catalyst preparation, polymer morphological development, and elementary chemical reactions. Metallocene-based cata lysts and their kinetic performance for olefin polymerizations are als o discussed. The current state of the art for reactor modeling of poly merization rate, molecular weight development, reactor dynamics, and r esin grade transition strategies is illustrated on the basis of the mo st recent academic studies. Finally, relationships between resin prope rties and polymer microstructures as well as characterization methods are described briefly. In particular, temperature-rising elution fract ionation technology is emphasized for characterization of ethylene cop olymers. The fundamental issues involved in gas phase ethylene polymer ization and their interrelationships are also discussed in some detail .