Abstract: There is disclosed a process for the stereoregular polymerization of alpha-olefins or mixtures thereof with ethylene, conducted in the presence of highly active and stereospecific new catalysts. The catalysts are obtained from the reaction of a particular Al-alkyl compound which is at least in part in the form of a complex and/or a substitution reaction product with an ester of an oxygenated organic or inorganic acid, with a supported component characterized by having surface area exceeding certain values or showing a particular X-rays spectrum, and obtained by contacting a Ti halogenated compound, preferably in the form of a complex with an electron-donor compound, with a support comprising a Mg or Mn bihalide.In the catalysts the ratio between the Ti compound, expressed in Ti g-atoms, and the g moles of the ester and the electron-donor compound, when present, is lower than 0.3.

Abstract: Polymers of .alpha.-olefin such as polyethylene, polypropylene, copolymers of ethylene with propylene, butene-1 or styrene, are produced by the (co-) polymerization using a catalyst obtained by mill-mixing an oxide of a metal belonging to I, II, III, VII or VIII Group of the Periodic Table of Elements such as MgO or SiO.sub.2 or B.sub.2 O.sub.3, with a trivalent metal halide such as AlCl.sub.3, then reacting the resultant mixture with a transition metal compound such as TiCl.sub.4 in the presence of an aromatic compound such as xylene, and activating the resultant solid reaction product with an organoaluminum compound such as triethyl aluminum.In the preparation of the present catalyst, no dehydrochlorination occurs. The present catalyst has an excellent utilization efficiency of transition metal compound in the polymerization. Further, no polymer film forms on the wall surface of the polymerization vessel.

Abstract: Catalysts, especially for olefin polymerization are prepared by coating an aluminum compound on a selected high pore volume silica gel, and calcining the support at temperatures of from about 200.degree. to 2000.degree. F. The preferred catalyst is prepared with an inorganic support material as aforesaid, thereafter depositing an organophosphoryl chromium compound thereon, and activating the thus-treated support by heating in a non-reducing, preferably oxygen-containing, atmosphere at temperatures of from about 800.degree. to 2000.degree. F. The activated, supported catalyst composition may, but need not necessarily, be combined with a metallic and/or non-metallic reducing agent, to provide a catalyst system useful in the polymerization of 1-olefins.BACKGROUND OF THE INVENTIONThe modification of silica gels for catalytic activity is known as discussed in Burwell, Chemtech, pp. 370-377 (1974).The use of chromium compounds in the polymerization of olefins is well-known. U.S. Pat. Nos.

Abstract: This invention discloses an improved catalyst for the polymerization or copolymerization of olefins, and a process for preparing polyolefins which comprises polymerizing or copolymerizing olefins using the said catalyst. According to the invention there is provided a process for preparing polyolefins by polymerizing or copolymerizing olefins using as a catalyst at least one compound selected from the group consisting of a titanium compound and a vanadium compound supported on a solid carrier, and an organometallic compound, said solid carrier comprising a product obtained by treatment with SO.sub.3 of at least one member selected from the group consisting of an oxide of Group II-IV metals of the Periodic Table and a double oxide of the said oxide and other oxide, which other oxide may be another oxide of Group II-IV metals of the Periodic Table or may be an oxide of other Group metals of the same Table.

Abstract: In the method of polymerizing .alpha.-olefins by contacting an .alpha.-olefin under polymerization conditions with a stereospecific catalyst comprising a titanium trichloride component and an organoaluminium compound, the improvement wherein said titanium trichloride component is ground during or after contact with a treating agent, said treating agent being selected from at least one ofA. an alkylene oxide, andB. a lactone.

Abstract: Olefin polymerization catalysts are prepared by depositing a chromium compound and an aluminum compound on an inorganic support material and heating the support material in a non-reducing atmosphere at a temperature above about 300.degree. C up to the decomposition temperature of the support material. The supported chromium and aluminum compound is then combined with a metallic and/or non-metallic reducing agent, to provide a catalyst system useful in the polymerization of 1-olefins.

Abstract: A process for polymerizing ethylene or a mixture of ethylene and another olefin is proposed in which the polymerization can be carried out with an extremely high efficiency by using a catalyst prepared by reacting (A) a hydrocarbon-insoluble reaction product (obtained by reacting (i) a specified organomagnesium-containing hydrocarbon-soluble complex, or reaction product of (i), with (ii) a specified siloxane compound and with (iii) at least one kind of titanium or vanadium compound containing at least one halogen atom), with (B) a specified organoaluminum compound. Resultant polymers have a high molecular weight and a high rigidity and molecular weight and molecular weight distribution thereof can be easily controlled.

Abstract: Olefin polymerization catalysts are prepared by depositing a chromium compound and an aluminum compound on an inorganic support material and heating the support material in a non-reducing atmosphere at a temperature above about 300.degree.C up to the decomposition temperature of the support material. The supported chromium and aluminum compound is then combined with a metallic and/or non-metallic reducing agent, to provide a catalyst system useful in the polymerization of 1-olefins.

Abstract: A method is herein disclosed by which a polymerizable monomer or a mixture thereof can be economically and efficiently converted to polymeric substances with a high yield catalyst in a vapor phase polymerization process using a stirred-bed, quench-cooled, horizontaL reactor together with essentially total reactor off-gas recycle and melt finishing. The method is further characterized by being essentially isobaric at least up to the polymer finishing steps.