Abstract: A solid catalyst component for alkene polymerization comprising a magnesium halide, an electron donor and a phenoxy-titanium halide, the latter being a dihalophenoxy-titanium halide or a dialkoxyphenoxy-titanium halide in which the alkoxy groups each have from 1 to 8 carbon atoms.

Abstract: A solid catalyst component for alkene polymerization comprising a magnesium halide, an electron donor and a phenoxy-titanium halide, the latter being a dihalophenoxy-titanium halide or a dialkoxyphenoxy-titanium halide in which the alkoxy groups each have from 1 to 8 carbon atoms.

Abstract: A process for preparing an olefin polymerization catalyst which comprises halogenating a magnesium-di-(3- or 4-halo- or 3- or 4-C.sub.1 to C.sub.8 alkoxy-phenoxide) with a halide of tetravalent titanium in the presence of a halohydrocarbon, recovering the solid reaction product from the reaction mixture and combining the solid reaction product with an organo aluminium compound and an electron donor.

Abstract: A process for preparing a solid catalyst component which comprises halogenating a magnesium compound in the formula MgRR.sup.1.nCO.sub.2 in which R and R.sup.1 are the same or different alkoxy or phenoxy groups and n is a number of from 0 to 2 with a halide of tetravalent titanium in the presence of dialkylester of a dihydric aromatic carboxylic acid and an inert hydrocarbon diluent by reacting at a temperature of from 120.degree. to 136.degree. C. and recovering the solid reaction product from the reaction mixture.

Abstract: A process for preparing an olefin polymerization catalyst which comprises halogenating a magnesium-di-(3-halo- or 3- C.sub.1 to C.sub.8 alkoxy-phenoxide) with a halide of tetravalent titanium in the presence of a halohydrocarbon, recovering the solid reaction product from the reaction mixture and combining the solid reaction product with an organo aluminium compound and an electron donor.

Abstract: A process for preparing a solid catalyst component which comprises halogenating a magnesium compound in the formula MgRR.sup.1.nCO.sub.2 l in which R and R.sup.1 are the same or different alkoxy or phenoxy groups and n is a number of from 0 to 2 with a halide of tetravalent titanium in the presence of dialkylester of a dihydric aromatic carboxylic acid and an inert hydrocarbon diluent by reacting at a temperature of from 120.degree. to 136.degree. C. and recovering the solid reaction product from the reaction mixture.

Abstract: Normally sparingly soluble magnesium alkoxide is solubilized in alkanol by the additional presence of certain acidic materials. The resulting solution is used to produce a mixture of substantially spherical particles, substantially free of fines, containing an adduct magnesium alkoxide. The particles are converted by conventional methods to a procatalyst precursor of an olefin polymerization catalyst of good activity and good selectivity to stereoregular polymer whenever appropriate, which catalyst produces polymer product of good morphology.

Abstract: A process for preparing spherical particles of a compound with the general formula Mg(OR).sub.2-a (OR').sub.a is disclosed. In the process R is an alkyl group with from 2 to 8 carbon atoms, R' is an alkyl group with from 1 to 7 carbon atoms and a is a number of from 0 to 0.5. The process comprises preparing a homogeneous solution of a compound Mg(OR).sub.2 in an aliphatic alcohol with the general formula R'OH, spray-drying the solution at a temperature of from 15.degree. to 85.degree. C., suspending the spray-dried solid particles in an aliphatic alcohol with the formula ROH in which R is the same alkyl group as present in the said compound Mg(OR).sub.2, heating the suspension in order to remove an alcohol with the formula R'OH from the liquid phase by distillation and separating the solid particles from the liquid phase.

Abstract: A process for preparing spherical particles of a compound with the general formula Mg(OR).sub.2-a (OR').sub.a is disclosed. In the process R is an alkyl group with from 2 to 8 carbon atoms, R' is an alkyl group with from 1 to 7 carbon atoms and a is a number of from 0 to 0.5. The process comprises preparing a homogeneous solution of a compound Mg(OR).sub.2 in an aliphatic alcohol with the general formula R'OH, spray-drying the solution at a temperature of from 15.degree. to 85.degree. C., suspending the spray-dried solid particles in an aliphatic alcohol with the formula ROH in which R is the same alkyl group as present in the said compound Mg(OR).sub.2, heating the suspension in order to remove an alcohol with the formula R'OH from the liquid phase by distillation and separating the solid particles from the liquid phase.

Abstract: A process for the preparation of polyisoprene by polymerizing isoprene in the presence of a beta-TiCl.sub.3 containing catalyst is disclosed thereby an activator is prepared by reacting a hydrocarbylaluminum compound and a hydroxy-aromatic compound, having at both ortho-places with respect to the hydroxy-group a secondary or tertiary alkyl-group.

Abstract: Composite polymers, especially composite polyols containing active hydrogen atoms can be prepared by polymerizing one or more olefinically unsaturated compounds in the presence of a liquid polymer containing active hydrogen atoms and a modified initiator; the modification comprising the reaction between a liquid polymer containing one or more groups which can react with isocyanato groups and a compound containing two or more isocyanato groups which has been partially converted by reacting it with an organic hydroperoxide or a free-radical initiator also containing additional active hydrogen atoms. The composite polymers exhibit a stable dispersed polymer phase and can be suitably applied as starting materials for polyurethane foams.