摘要 |
<p>Process for the preparation of a solid olefin polymerisation catalyst system, comprising an organometallic compound of a transition metal of Group 3 to 10 of the Periodic Table (IUPAC 2007) in the form of solid particles comprising the steps of
a) preparing a solution (A) comprising
a1) a transition metal compound of formula (I)
€ƒ€ƒ€ƒ€ƒ€ƒ€ƒ€ƒ€ƒ L n R n MX q €ƒ€ƒ€ƒ€ƒ€ƒ(I)
wherein
"M" is a transition metal of anyone of the groups 3 to 10 of the periodic table (IUPAC 2007), preferably a transition metal of anyone of the groups 4 to 6 of the periodic table (IUPAC 2007), more preferably titanium (Ti), zirconium (Zr) or hafnium (Hf), i.e. zirconium (Zr) or hafnium (Hf),
each "X" is independently a monovalent Ã-ligand,
each "L" is independently an organic ligand which coordinates to the transition metal (M),
"R" is a bridging group linking said organic ligands (L),
"m" is 2 or 3, preferably 2,
"n" is 0, 1 or 2, preferably 1,
"q" is 1, 2 or 3, preferably 2,
m+q is equal to the valency of the transition metal (M),
a2) a cocatalyst comprising an element of group 13 of the Periodic Table (IUPAC 2007), preferably a cocatalyst (Co) comprising a compound of AI and
a3) a solvent (A-1),
b) preparing a liquid/liquid emulsion system by dispersing the solution (A) in a solvent (B) wherein
b1) the solvent (B) constitutes the continuous phase of the emulsion and comprises a nonreactive fluorinated synthetic oil like a perfluoropolyether, a polytrichlorofluoroethylene, a fluorosilicone, or combinations thereof, having a viscosity at 20°C of at least 10 cSt according to ASTM D445
b2) the solution (A) constitutes in the form of droplets the dispersed phase and
b3) the transition metal compound of formula (I) and the cocatalyst (Co) are present in the droplets,
c) solidifying said dispersed phase to convert said droplets to solid particles and
d) optionally recovering said particles to obtain said catalyst system.</p> |