title: Donor/Acceptor Metallocenes: A New Structure Principle in Catalyst Design.
abstract: Suitable as highly effective polymerization catalysts is the new class of donor/acceptor metallocenes in which the rotation of the two pi ligands is restricted through the formation of a dative D(+)-->A(-) bond (see picture). Specifically optimized substitution patterns yield excellent properties for the synthesis of high-melting, highly crystalline thermoplastic materials, amorphous thermoplastic materials with high glass transition temperatures as well as polyolefin elastomers with low glass T(g).
authors.affiliation: Bayer AG, Zentrale Forschung, Wissenschaftliches Hauptlaboratorium, D-51368 Leverkusen (Germany).
authors.lastname: Ostoja Starzewski KA
authors.initials: WM
authors.lastname: Kelly
authors.initials: A
authors.lastname: Stumpf
authors.initials: D
authors.lastname: Freitag