| abstract |
High melting-point polyolefins can be produced as such, in solution, suspension or gas phase, metallocene compounds of formula (I) or π-complex compounds of formulas (I) or (XIII) being used as catalysts. In said formulas: CpI and CpII represent carbanions with a structure containing cyclopentadienyl; πI and πII represent charged or electrically neutral π-systems; D represent a donator atom and A an acceptor atom, D and A being linked by a reversible, co-ordinative bond such that the donator group adopts a positive (partial) charge and the acceptor group a negative (partial) charge; M stands for a transitional metal of the IIIrd, IVth, Vth or VIth subgroup of the periodic system of elements (Mendeleev's table) including lanthanides and actinoides; X stands for an anion equivalent; and n, depending on the charge of M, stands for the figure nought, one, two, three or four. |