Patent EP-0225452-A1 (EP)
Inventor: VOGT HEINZ DR
IPC: C08F4/64
Filed: 1986-10-16
Abstract: 1. A process for preparing a copolymer of ethylene with a minor amount of a C3 -C8 -monoolefin by polymerization of the monomers at from 30 to 200 degrees C and from 1 to 200 bar by means of a Ziegler catalyst system composed of (1) a titanium-containing catalyst component and (2) an aluminum-containing catalyst component of the formula AlR3 , where R3 is C1 -C12 -hydrocarbyl, with the proviso that (i) the atomic ratio of titanium in catalyst component (1) : aluminum in catalyst component (2) is within the range from 1:5 to 1:700 and (ii) the titanium-containing catalyst component (1) used is the solid-phase product (VI) obtained by (1.1) initially bringing into contact with each other (1.1.1) a finely divided, porous, inorganic oxide substance (I) which has a particle diameter of from 1 to 1,000 mu m, a pore volume of from 0.3 to 3 cm**3 /g, a surface area of from 100 to 1,000 m**2 /g and the formula SiO2 .aAl2 O3 , where a is from 0 to 2, and (1.1.2) a solution (II) as obtained on adding together (IIa) 100 parts by weight of alcohol of the formula R**1 -OH, where R**1 is saturated C1 -C8 -hydrocarbyl, (IIb) from 0.01 to 6 parts by weight (calculated at titanium) of a titanium trichloride of the formula TiCl3 .nAlCl3 , where n is from 0 to 0.5, and (IIc) from 0.01 to 4 parts by weight (calculated as magnesium) of magnesium chloride (MgCl2 ), to form a dispersion (III), with the proviso that the weight ratio of inorganic oxide substance (I) : titanium in titanium trichloride (IIb) is within the range from 1:0.01 to 1:0.2 and the weight ratio of inorganic oxide substance (I) : magnesium in magnesium chloride (IIc) is within the range from 1:0.01 to 1:0.25, evaporating the dispersion (III) at a temperature which is below 200 degrees C and above the melting point of the alcohol (IIa) used until dry, to form a solid-phase intermediate (IV), and (1.2) then bringing into contact with each other (1.2.1) the solid-phase intermediate (IV) obtained from stage (1.1) and (1.2.2) an aluminum component (V) containing C1 -C12 -hydrocarbyl as well as aluminum, dissolved in an inert hydrocarbon, to form a dispersion wherein the solid-phase product (VI) resulting as the dispersed phase is titanium-containing catalyst component (1), which comprises using as the titanium-containing catalyst component (1) the solid-phase product (VI) which has been obtained from stage (1.2) by using therein as an aluminum component (V) an aluminum component consisting (1.2.2.1) to an extent of from 25 to 100 mol % of a complex which is soluble in the inert hydrocarbon and has the empirical formula  see diagramm : EP0225452,P11,F1  or  see diagramm : EP0225452,P11,F2  where m is 1 or 2, n is 1, 2 or 3 R**2 and R**3 and R**4 and R**5 are each C1 -C12 -hydrocarbyl and R**6 is C1 -C12 -hydrocarbyl or chlorine and (1.2.2.2) to an extent of from 0 to 75 mol % of an aluminum compound which is soluble in the inert hydrocarbon and has the formula  see diagramm : EP0225452,P11,F3 where R**4 and R**5 are each C1 -C12 -hydrocarbyl and R**6 is C1 -C12 -hydrocarbyl or chlorine, with the proviso that (i) the mol % under (1.2.2.1) and (1.2.2.2) add up to 100 and (ii) the atomic ratio of titanium in the solid-phase intermediate (IV) : aluminum in aluminum component (V) is within the range from 1:1 to 1:30.