Question

Discuss the effect of the change in structure of the metallocene catalyst on the tactility and molecular weight of resultant polymer

Answer 1

metallocene catalysts open the possibility to synthesize polymers with highly defined microstructure, tacticity, and steroregularity, as well as long-chain branched, or blocky copolymers with excellent properties

metallocene are more homogeneous both in molecular weight, in tacticity, and tacticity distributions; chains resemble one another much more than when using Ziegler-Natta catalysts because of the presence of only one active center in metallocene catalysts

large molecular weights are more difficult to obtain in metallocene polyolefins. Due to these features the applications of these newer polyolefins have been significant in the elastomeric, low tacticity types than in the high isotactic, high-melting point ones