Patent ID: 7649061

Claim:
A process for preparing a poly-1-olefin by polymerizing a 1-olefin of formula R 4 CH═CH 2 , wherein R 4 is hydrogen or an alkyl radical comprising from 1 to 10 carbon atoms, in suspension, solution, or gas phase, at a temperature of from 20 to 200° C. and a pressure of from 0.5 to 50 bar, in presence of a catalyst comprising: a component (a) comprising a reaction product of a magnesium alkoxide with a transition metal compound; and a component (b) comprising an organometallic compound; the process comprising: dry milling in a mill under inert conditions an initial magnesium alkoxide powder comprising a mean particle size, expressed as d 50 , ranging from 100 to 1000 μm to produce a finer magnesium alkoxide powder comprising a mean particle size, expressed as d 50 , of less than 15 μm; suspending the finer magnesium alkoxide powder in an inert hydrocarbon, wherein the finer magnesium alkoxide powder is insoluble in the inert hydrocarbon to produce a magnesium alkoxide powder suspension; and immediately reacting, without further pretreatment, the magnesium alkoxide powder suspension with a transition metal compound comprising titanium, zirconium, vanadium or chromium to produce component (a).