Patent ID: 6730627
Filing Date: 2004-05-04
Classification: C08F

Abstract:
A solid component of a catalyst for the (co)polymerization of ethylene and &agr;-olefins, which contains magnesium-carboxylate bonds and transition metal-carboxylate bonds; which is represented by the formulaM1Mg(0.3-20)X(2-60)Al(0-6)(Râ€”COO)(0.1-3)â€ƒâ€ƒ(I); and which is prepared by the steps of:(a) forming a solution, in an inert organic solvent, of a magnesium carboxylate or a magnesium carboxylate halogenide having the formula MgXn(Râ€”COO)2âˆ’n (II), where n ranges from 0 to 1, and at least one transition metal carboxylate or transition metal carboxylate halogenide having the formula MXm(Râ€”COO)4âˆ’m (III), where the atomic ratio between the magnesium in (II) and the transition metal in (III) is from 0.3:1 to 20:1; (b) adding to the solution an aluminum alkyl halide (IV), where the alkyl group is a linear or branched alkyl group containing 1-20 carbon atoms and the halide group is a halide other than an iodide group, to precipitate the solid component of the catalyst, where the atomic ratio between the halide in (IV) and the total carboxyl groups in (II) and (III) is from 0.3:1 to 10:1; and (c) recovering the solid component in a granular form; where M in formulas (I) and (III) is at least one transition metal selected from the group consisting of titanium or a mixture of titanium and zirconium or hafnium, with the atomic ratio between the titanium and the zirconium or hafnium being 0.25:1 to 2:1 and wherein the aluminum alkyl halide has the formula AlRâ€²pX(3âˆ’p), where Râ€² is the C1-C20 linear or branched alkyl group, X is the halide group other than the iodide group, and p is between 1 and 2; X in formulas (I), (II), (III), and (IV) is a halogen other than iodine; R in formulas (I), (II), and (III) is an aliphatic, cycloalipathic, or aromatic radical containing at least 4 carbon atoms; and m is from 0 to 2.