Abstract: A solid catalyst component prepared under specific conditions by reacting with a reaction product which has been obtained by suspending diethoxymagnesium in an alkylbenzene and bringing the suspension into contact with titanium tetrachloride, phthaloyl dichloride at 80.degree.-125.degree. C.

Abstract: A solid catalyst component prepared by admixing and reacting, with a reaction product which has been obtained by suspending diethoxymagnesium in an alkylbenzene and bringing the suspension into contact with titanium tetrachloride in an amount less than 1 in terms of volume ratio to the alkylbenzene, a phthaloyl dichloride at a temperature within the range between 80.degree. C. and 125.degree. C., washing the resultant solid substance with an alkylbenzene, and reacting the solid substance in the presence of an alkylbenzene with titanium tetrachloride in an amount less than 1 in terms of volume ratio to the alkylbenzene as well as an olefin polymerization catalyst which comprises (A) the above specified solid catalyst component, (B) a silicon compound of the general formula: SiR.sub.m (OR').sub.

Abstract: A catalyst for the polymerization of olefins which exhibits a high catalytic activity and is capable of producing a stereoregular polymer in a high yield. The catalyst includes a catalyst component for the polymerization of olefins prepared by subjecting a solid composition obtained by a process comprising contacting dialkoxymagnesium, diester of aromatic dicarboxylic acid, aromatic hydrocarbon and titanium halide to a heat treatment in the presence or absence of a solvent; a silicon compound; and an organic aluminum compound.

Abstract: A catalyst for the polymerization of olefins which comprises:(A) a solid catalyst component prepared by bringing a co-ground product of a substance (a) obtained by reacting magnesium with at least two molar proportion of an alkyl monohalide in the absence of a solvent but in the presence of iodine and a dialkyl phthalate (b) and optionally existing titanium tetrachloride (c) into contact with titanium tetrachloride in the presence or absence of an aromatic hydrocarbon and/or halohydrocarbon.(B) a 2,6-dialkyl- or 2,2,6,6-tetraalkyl-piperidine derivative, and(C) an organoaluminum compound selected from a trialkyl aluminum, a dialkylaluminum halide and an alkylaluminum dihalide, as well as the solid catalyst component (A) for the catalyst. This catalyst characterized by the use of the specific solid catalyst component exhibits a high polymerization activity combined with stereospecific performance over a prolonged polymerization time and is free from any problem of corrosion and odor in the resultant polymer.

Abstract: A catalyst for the polymerization of olefins comprising:(A) a catalyst component obtained by a process comprising contacting (a) a fatty acid salt of magnesium and (b) dialkoxymagnesium, (c) mono or diester of an aromatic dicarboxylic acid, (d) a halogenated hydrocarbon and (e) a titanium halide of the general formula: TiX.sub.4, wherein X represents a halogen atom;(B) a silicon compound represented by the general formula: SiR.sub.m (OR').sub.4-m, wherein R is hydrogen, alkyl group or aryl group, R' is alkyl group or aryl group, and m is represented as O.ltoreq.m.ltoreq.4; and(C) an organoaluminum compound.Polymerization of olefins by use of the catalyst provides such advantages as high polymerization activity per unit weight of the catalyst component, prolonged polymerization activity, high yield of stereoregular polymer, and a produced polymer free of such an estereal odor as in the prior art.