Ziegler-Natta catalyst component - prepd. by reacting titanium tetra:chloride with phenylene ester and then with magnesium alcoholate

摘要

Modified Ti component for a Ziegler-Natta system is prepd. by bringing together 100 pt. vol. TiCl4 and 1-20 pt. vol. phenyl(ene) ester or acid of formula R3-Ph-CuH2n-COOR4 (I) (where R3 is H, 1-4C alkyl or 1-4C alkoxy; R4 is H or 1-4C alkyl and n is 0-3), maintaining the mixt. at 30-100 deg.C until a homogeneous liq. is formed; adding a magnesium alcoholate (II) of formula Mg(OD)2 (where D is a monovalent satd. aliphatic and/or aromatic 1-8C hydrocarbon gp.) with a particle diameter of 0.05-5.0 mm to the liq. in a mol. ratio of (I):(II) of 1:12-1:1, stirring the mixt. continuously for 0.2-4 hrs. at 40-180 deg.C, sepg. off the solids, mixing 100 pt. wt. TiCl4, 0.2-100 pt. wt. solid prod. from above and opt. up to 15 pt. wt. (I) for 1-5 hrs. at 40-180 deg. and separating off the final prod. The component can be in catalyst systems which esp. at relatively high polymerisation temps. influence morphological properties of the polymer e.g. uniform particle size, reducing the amt. of fines, high bulk density and/or flow without reducing stereoregularity and yield.