摘要 |
A catalyst suitable for the polymerization of ethylenically unsaturated compounds. A bidentate ligand with general formula (I) in which X = P, As, Sb, n = 0 or 1, R1, R2 = alkyl, alkoxy, aryloxy, cycloalkyl or a substituted or non-substituted (cyclo)aliphatic, (cyclo)olefinic or aromatic group with 1-24 C-atoms, or R1 and R2 may form together a substituted or non-substituted cycloaliphatic, cyclo-olefinic or aromatic group, R3, R4, R7, R8 = H, alkyl, alkoxy, aryloxy, cycloalkyl or a substituted or non-substituted (cyclo)aliphatic, (cyclo)olefinic or aromatic group with 1-24 C-atoms, and if n = 1:R5 and/or R6 = H, alkyl, alkoxy, aryloxy, cycloalkyl or a substituted or non-substituted (cyclo)aliphatic, (cyclo)olefinic or aromatic group with 1-24 C-atoms, and C' and C'' together with R3 and R6 may form a substituted or nonsubstituted (cyclo)aliphatic, (cyclo)olefinic or aromatic group, R4 and R5 being absent in this case, or C' and C'' may form an olefinic bond, R4 and R5 being absent in this case, with a source of cations of a metal of group 8, 9 or 10 of the Periodic Table of Elements and an acid having a pKa of less than 4. |