Abstract: Granular stereoregular butene-1 polymers having a high isotactic content, and an extractables content of no more than about 15 weight percent in boiling ethyl ether, are produced over a continuous extended period of time in a low pressure gas phase fluidized bed process, in the absence of liquid diluent components, with a stereospecific olefin polymerization catalyst under a selected set of operating conditions.

Abstract: A titanium trichloride catalytic component and a method for homo- or co-polymerization of an .alpha.-olefin. In separating a titanium trichloride catalytic component from a solution prepared by dissolving titanium tetrachloride, an organic ether compound and an organo-aluminum compound in a solvent, the above stated solvent is a mixed solvent prepared by allowing 20.about.70% by volume of an aromatic hydrocarbon halide to be concomitant with a saturated aliphatic hydrocarbon and/or an alicyclic hydrocarbon in the presence of an olefin; the organo-aluminum compound, the titanium tetrachloride and the organic ether compound are added to the mixed solvent at a solvent temperature not exceeding 55.degree. C.; then, the solvent temperature is raised to a temperature between 45.degree. and 150.degree. C.

Abstract: Polyolefin granules having an average particle size diameter greater than 600 microns, preferably about 1000 microns or greater are obtained by polymerizing monoolefins in the presence of a titanium catalyst having an average particle size diameter of greater than about 35 microns and preferably 40 to 65 microns. The titanium catalysts are obtained by reducing titanium tetrahalide in the presence of a suitable organometallic reducing compound such as diethylaluminum chloride under controlled conditions of temperature, reduction rate and concentrations to obtain a titanium halide reduced solids product seeds having an average particle size diameter of about 20 microns or greater and thereafter simultaneously and without interruption adding to the seeds containing system titanium tetrahalide and organometallic reducing compound such as diethylaluminum halide at a rate such that the reduction of titanium tetrahalide to titanium trihalide is about 6.times.10.sup.-4 to about 0.

Abstract: A titanium trichloride catalytic component obtained by separating it out of a solution consisting of titanium tetrachloride, an organic ether compound and an organo-aluminum compound dissolved in a solvent. The solvent is a mixture consisting of a saturated aliphatic hydrocarbon and/or an alicyclic hydrocarbon with 20 to 70% by volume of a concomitant aromatic hydrocarbon halide included therein. The organo-aluminum compound, the titanium tetrachloride and the organic ether compound is added to this mixed solvent at a solvent temperature not exceeding 55.degree. C. Following this, the solvent temperature is raised up to a value between 45.degree. and 150.degree. C. over a period of 10 minutes to 24 hours with an organic ether compound and/or titanium tetrachloride further added during this temperature raising process to obtain thereby a titanium trichloride catalytic component having average particle diameter between 10 and 1000.mu.. Then homo- or co-polymerization of .alpha.

Abstract: A catalyst for the polymerization of olefins is described wherein a titanium(IV) compound is reduced with an organoaluminum compound in the presence of atactic poly-.alpha.-olefin. Polymerization with the catalyst is also disclosed.

Abstract: A titanium trichloride-catalyzed process for stereospecific polymerization of alpha-olefins, particularly propylene, to produce polymers of relatively high bulk density comprises employing as the TiCl.sub.3 catalyst component, used with an aluminum alkyl cocatalyst, a 0.1 to 30 millimicron fraction of a TiCl.sub.3 composition produced by(a) reacting TiCl.sub.4 with a complexing agent in a molar ratio of from 1:0.3 to 1:2;(b) reacting an organo-aluminum compound with a complexing agent in a molar ratio of at most 1:0.25;(c) reducing the complexed TiCl.sub.4 with the complexed organo-aluminum compound over a period of less than one hour at a temperature within the range 60.degree. to 110.degree. C. to produce TiCl.sub.3 particles having an average particle size of from 50 to 500 .mu.m;(d) subjecting the TiCl.sub.3 particles to a treatment to reduce the average particle size thereof to less than 50 .mu.m, and(e) classifying the TiCl.sub.

Abstract: An improved method for the polymerization of vinyl chloride or a monomer mixture mainly composed of vinyl chloride in an aqueous polymerization medium is proposed in which a water-insoluble polymerization initiator, being solid at room temperature as dispersed in the aqueous medium and having a particle size distribution of 50 .mu.m or finer, is added to the polymerization mixture which is maintained at a temperature where the half-life period of the initiator is 120 minutes or longer or, alternatively, over a duration equal to or shorter than one-tenth of the half-life period of the initiator at the temperature of the polymerization mixture. By this method the polymerization can be homogeneously proceeded to produce vinyl chloride polymers having a uniform particle size distribution, excellent heat stability and much less fish-eyes when fabricated into sheets.

Abstract: Process for the preparation of a porous, pure silica which is particularly suitable as a catalyst support for a chromium-oxide catalyst used in polymerizing of olefins. The process comprises the steps of converting a silicon-halogen compound to a silica and then admixing with water to form a silica gel. The gel is then spray-dried to achieve the required particle size and pore volume.The silica can then be made into a catalyst by placing on the support a chromium compound and then heating in a non-reducing atmosphere.

Abstract: Process for the preparation of a porous, pure silica which is particularly suitable as a catalyst support for a chromium-oxide catalyst used in polymerizing of olefins. The process comprises the steps of converting a silicon-halogen compound to a silica and then admixing with water to form a silica gel. The gel is then dried and ground to a predetermined particle size. The silica can then be made into a catalyst by placing on the support a chromium compound and then heating in a non-reducing atmosphere.

Abstract: Solid catalytic complexes are useful for stereospecific polymerization of .alpha.-olefins to solid crystalline polymers. The complexes are formed by reducing TiCl.sub.4 with an alkylaluminum, treating thus-obtained reduced solid with a complexing agent and contacting the resultant with TiCl.sub.4. They have a specific surface greater than 75 m.sup.2 /g.

Abstract: Gas-phase polymerization of an .alpha.-olefin, especially propylene, in a stirred or fluidized bed of substantially uniform and approximately spherical carrier particles of an .alpha.-olefin polymer of diameter 100-500 .mu.m, using a catalyst comprising an organo-metallic compound and a solid transition metal compound which has a particle size of less than 5 .mu.m, produces a propylene polymer having unexpectedly good powder flow characteristics. The transition metal compound is conveniently a titanium trichloride-containing material which has been treated with a dialkyl ether solution.

Abstract: Organic peroxide compositions suitable for free radical polymerization, the compositions comprising a mixture of a shock-sensitive peroxide and a diluent, the diluent being a monomeric material containing olefinic unsaturation which does not readily homopolymerize.

Abstract: Solid titanium trichloride in the form of fine granules having low aluminum compound content, which is suitable as a catalyst for polymerization of .alpha.-olefins, especially, propylene is obtained as a precipitate by heating liquefied titanium trichloride in the presence of a liberating agent, and separating the thus formed precipitate. The liquefied titanium trichloride is preferably prepared with an reducing titanium tetrachloride by organic aluminium compound in the presence of ether and hydrocarbon.

Abstract: Polymerization of ethylene using a transition metal hydrocarbyl complex, especially zirconium tetrabenzyl, supported on alumina consisting of substantially spherical particles having diameters in the range 20-150 .mu.m. The particulate polymer produced by the process contains substantially no "fines" (i.e. particles <100 .mu.m diameter) and has improved pourability.