Triple tandem catalyst mixtures for the synthesis of polyethylenes with varying structures.

Tandem catalysis in a single medium presents challenges and opportunities for creating novel synthetic protocols. Thus far, only two homogeneous catalysts have been used in tandem. Herein, we report that it is possible to coordinate the action of three well-defined homogeneous catalysts to produce a wide range of branched polyethylenes from a single monomer.

Alternating Ethene/Propene Copolymerization with a Metallocene Catalyst.

A small variation in the substituent R' on the metallocene catalyst employed in the copolymerization of ethene and propene leads to a highly alternating (81-83%) structure (1) rather than a statistical copolymer. Such copolymers were until recently only accessible by hydrogenation of polyisoprene or 1,4-poly(pentadiene).