Patent DE-2838989-A1 (DE)
Inventor: KLAERNER PETER DIPL CHEM DR
IPC: C08F4/64
Filed: 1978-09-07
Abstract: 1. Process for the preparation of homopolymers and copolymers of C2 -C6 -alpha-monoolefines by polymerization of the monomer or monomers at temperatures of 30 to 200 degrees and pressures of 0.1 to 200 bar by means of a Ziegler catalyst system comprising (1) a titanium-containing catalyst component which has been obtained using (i) a finely divided, porous, inorganic-oxidic substance (Ib), which has a particle diameter of 1 to 1000 mu m, a pore volume of 0.3 to 3 cm**3/g and a surface area of 100 to 1000 m**2/g and has the formula SiO2 . aAl2 O3 , wherein a represents a number in the range from 0 to 2, and (ii) a solution (II) which results on bringing together (IIa) 100 parts by weight of an alcohol, in the form of an individual compound or of a mixture of two or more individual compounds, of the general formula Z-OH wherein Z represents a saturated C1 - to C8 -hydrocarbon radical, (IIb) 0.01 to 6 parts by weight (calculated as titanium) of a titanium trihalide, wherein the halogen can be chlorine and/or bromine, and (IIc) 0.001 to 4 parts by weight (calculated as magnesium) of a magnesium compound, in the form of an individual compound or of a mixture of two or more individual compounds, which is soluble in the alcohol (IIa), with the provisos that the weight ratio of inorganic-oxidic substance (Ib) : titanium in the titanium trihalide (IIb) is in the range from 1:0.01 to 1:0.2 and the weight ratio of inorganic-oxidic substance (Ib) : magnesium in the magnesium compound (IIc) is in the range from 1:0.01 to 1:0.25, and (2) a metal compound of the general formula MeAm-n Xn wherein Me represents the metals aluminium, magnesium or zinc, A represents a C1 - to C12 -hydrocarbon radical, X represents chlorine, bromine, iodine or hydrogen, m represents the numerical value of the valency of the metal Me and n represents a number from 0 to m-1, with the proviso that the atomic ratio of titanium from the catalyst component (1) : metal (Me) from the catalyst component (2) is in the range from 1:0.1 to 1:500, characterized in that the titanium-containing catalyst component (1) employed is the solid-phase substance from a suspension which has been obtained by (1.1) in a first stage initially (1.1.1) bringing into contact a suspension (I), which is obtained on bringing together (Ia) 100 parts by weight of a hydrocarbon which is liquid under normal conditions and is inert towards Ziegler catalyst systems and (Ib) 0.1 to 100 parts by weight of the finely divided, porous, inorganic-oxidic substance (Ib) and (1.1.2) the solution (II) - with the proviso that the alcohol (IIa) contained therein must be liquid under normal conditions and be soluble to the extent of less than 10 per cent by volume in the hydrocarbon (Ia) - to form a dispersion (III), thereafter (1.2) in a second stage, subjecting the dispersion (III) obtained from stage (1.1) - if appropriate with supplementation of the hydrocarbon (Ia) - to azeotropic distillation at a temperature of between 10 and 140 degrees C, with formation of a suspension, until alcohol no longer passes over in the distillate, and thereafter (1.3) in a third stage, adding to the suspension obtained from stage (1.2) a metal compound (IV) of the general formula MtGs-t Et wherein Mt represents the metals aluminium or silicon, G represents a C1 - to C12 -hydrocarbon radical, E represents chlorine, bromine, iodine, hydrogen or a -OD radical, D represents a C1 - to C12 -hydrocarbon radical, s represents the numerical value of the valency of the metal Mt and t represents a number from (a) 0 to s-1, if Mt is aluminium or (b) 0 to 4, if Mt is silicon, whilst maintaining the state of a suspension, and with evolution of a gas, the addition being continued until no more gas is evolved.