Ring-opening polymerization (ROP) of strained ring-tilted metallocenophanes can be achieved thermally, via anionic initiation, or by the use of transition metal catalysts and provides access to a wide range of high molecular weight (Mw ˆ 10 ±10, Mn> 10 ) poly(metallocenes). These materials possess a variety of interesting properties and many are very easy to prepare. This article provides an ov...

The rheology of linear and branched metallocene polyethylenes (m-PEs) was investigated. The linear metallocenes were prepared by gas-phase polymerization, while the branched PEs were commercial resins. Molecular parameters such as Mw, branch type, and molecular weight distribution have influenced the viscoelastic behavior of both linear and branched PEs, whereas branch content (BC) had little i...

Deviating from the common growth mode of molecular films of organic molecules where the adsorbates remain intact, we observe an essentially different growth behavior for metallocenes with a low temperature scanning tunneling microscope. Ferrocene molecules adsorb dissociatively and form a two layer structure. The top layer unit cell is composed of two tilted cyclopentadienyl (cp) rings, while t...

Research on "post-metallocene" polymerization catalysis ranges methodologically from fundamental mechanistic studies of polymerization reactions over catalyst design to material properties of the polyolefins prepared. A common goal of these studies is the creation of practically useful new polyolefin materials or polymerization processes. This Review gives a comprehensive overview of post-metal...

Bis(1-methylethenyl-cyclopentadienyl)zirconium dichloride (7a) was prepared by a fulvene route. Photolysis at 0 degrees C with Pyrex-filtered UV light resulted in a rapid and complete intramolecular [2+2]cycloaddition reaction to yield the corresponding cyclobutylene-bridged ansa-zirconocene dichloride isomer (8a). This is one of the rare examples of an organic functional group chemistry that l...

We systematically assessed the cytotoxic effects of five metallocene dichlorides containing vanadium (vanadocene dichloride), titanium (titanocene dichloride), zirconium (zircodocene dichloride), molybdenum (molybdocene dichloride), and hafnium (hafnocene dichloride) as the central metal atom and 19 other vanadocene complexes. These compounds were tested against the human testicular cancer cell...