Ethene-norbornene copolymerization with homogeneous metallocene and half-sandwich catalysts: Kinetics and relationships between catalyst structure and polymer structure. 3. Copolymerization parameters and copolymerization diagrams

摘要

The copolymerization parameters of the ethene-norbornene copolymerization using various metallocene and half-sandwich catalysts were determined on the basis of composition data with linear graphical methods: Aside from r(1) and r(2), values for r(11) and r(21) could be determined in the case of alternating copolymerizations. In this connection, r(21) differs significantly from catalyst to catalyst and reflects the different tendency of each catalyst to produce copolymers with an alternating monomer sequence. The maximum norbornene contents in the copolymer could be achieved by use of sterically less hindered metallocene catalysts. As an exception to this, the half-sandwich catalysts produced copolymers with surprisingly low norbornene contents. [References: 14]