Chapter 3 Kinetics of Polymerization Initiated by Ziegler—Natta and Related Catalysts

摘要: Publisher Summary The kinetic studies on polymerizations using coordination catalysts present considerable difficulties owing to their complexity and variability, the incomplete understanding of reaction mechanisms, problems in handling highly reactive many cases heterogeneous systems. It is essential, for a proper appreciation kinetics data, that there should be some knowledge catalyst structures polymerization mechanism. Ziegler Natta exhibit great variations stability activity, polymer yield varies greatly with different monomers. Ziegler-Natta are difficult study experimentally, particularly those based insoluble transition metal compounds. They also complicated by interaction concurrent chemical reactions physical processes may have either accelerating or retarding influences polymerization. presence absence monomer during preparation Catalyst stoichiometry can major effects; loss activity usually ascribed decomposition organo-transition complex. Organo-transition compounds vary stability, but frequently stabilized complexation other adsorption halides. nature groupings attached pronounced influence stability.