Catalyst support and catalyst for the polymerization of alpha-olefins; processes for obtaining them and polymerization of alpha-olefins in presence of the catalyst
AssigneeSolvay (Soci et e Anonyme)
InventorsJean-Louis Costa, Vincent Laurent, Philippe Francois, Dirk Vercammen
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Abstract
Catalyst support containing an .alpha.-olefin polymer which is in the form of particles of mean size from 5 to 350 .mu.m in which the pore volume generated by the pores of radius from 1,000 to 75,000 .ANG. is at least 0.2 cm.sup.3 /g. Catalyst usable for the polymerization of .alpha.-olefins, including a compound containing at least one transition metal belonging to groups IIIb, IVb, IVb and VIb of the Periodic Table, bound in or on this support.
Claims3
A catalyst support comprising at least one .alpha.-olefin polymer which is in a form of particles of mean size from 5 to 350 .mu.m, in which a pore volume generated by pores of radius from 1,000 to 75,000 .ANG. is at least 0.2 cm.sup.3 /g, said support being obtained by polymerization of one or more .alpha.-olefins by means of a catalytic system (S) containing a catalytic compound (a) which is obtained by heat treatment, in a presence of a halogen-containing agent, of a liquid material resulting from placing titanium tetrachloride (TiCl.sub.4) pretreated with an electron-donor compound into contact with a composition (D) corresponding to a general formula of
- AlR.sub.p (Y).sub.q X.sub.3-(p+q) (II)
- in which
- R denotes a hydrocarbon radical;
- Y denotes a group chosen from OR', --SR' and --NR'R" in which each of R' and R" denotes a hydrocarbon radical or a hydrogen atom;
- X denotes a halogen;
- p is any number such that 0.ltoreq.p2.5;
- q is any number such that 0.5<q<3, the sum (p+q) being such that 0.5<(p+q).ltoreq.3 and an activator chosen from organoaluminium compounds in such a way that a quantity of catalyst residue, expressed as g of compound (a) per kg of support, is at least approximately 5 and smaller than or equal to 170.
Dependencies are inferred from the claim text.