Abstract: An improved chromate catalyst on a highly porous silica support having high surface area and total pore volume, a method of using same to produce high performance polyethylene products, and the high performance polyethylene products, such as polyethylene pipe, produced thereby.

Abstract: An improved chromate catalyst on a highly porous silica support having high surface area and total pore volume, a method of using same to produce high performance polyethylene products, and the high performance polyethylene products, such as polyethylene pipe, produced thereby.

Abstract: A process is disclosed for producing polyethylene resin of broad molecular weight distribution, when formed into a film, high barrier to moisture (low MVTR (Moisture Vapor Transmission Rate) for the film). The resin is formed by polymerizing ethylene, preferably in a gas phase process or in a slurry process, using a post-titanated catalyst, that is, a catalyst wherein after initial formation of a catalyst comprising Cr—Ti-inorganic refractory support, further titanium is added to the catalyst in a post-titanation step, preferably to increase the titanium content of the catalyst to a final level preferably between 7 and 9.5 wt. %.

Abstract: A process is disclosed for producing polyethylene resin of broad molecular weight distribution, when formed into a film, high barrier to moisture (low MVTR (Moisture Vapor Transmission Rate) for the film). The resin is formed by polymerizing ethylene, preferably in a gas phase process or in a slurry process, using a post-titanated catalyst, that is, a catalyst wherein after initial formation of a catalyst comprising Cr—Ti-inorganic refractory support, further titanium is added to the catalyst in a post-titanation step, preferably to increase the titanium content of the catalyst to a final level preferably between 7 and 9.5 wt. %.

Abstract: A polymerization process is provided comprising contacting under polymerization conditions a catalyst, a taming agent, ethylene and optionally a comonomer, wherein the catalyst comprises chromium oxide, titanium oxide and an inorganic refractory oxide, wherein the taming agent is selected from the group consisting of water, alcohols, aldehydes, ketones, esters, and organic acids and mixtures thereof. The process is especially suited for polymerizing ethylene resins suitable for blow molding use.

Abstract: Disclosed is a process for making polyethylene resin by reacting ethylene or ethylene and a C.sub.3 -C.sub.8 alpha-olefin in the presence of a CrO.sub.3 /TiO.sub.2 catalyst on a silica support in a gas-phase polymerization reactor and in the presence of a catalyst productivity reduction agent such as oxygen. The resin in one embodiment has a melt flow ratio between 65 and 140 and a melt index between 0.1 and 0.6 g/10 min. The resin is particularly suitable for use in blow-molding applications.

Abstract: Apparatus is provided to feed controlled quantities of a catalyst slurry to an olefin polymerization reactor in a controlled time sequence. The apparatus includes a feed line for continuously feeding an inert hydrocarbon liquid such as hexane or isobutane to the reactor. A bypass loop is provided in the feed line and is equipped with auxiliary apparatus to charge the loop with a predetermined quantity of catalyst slurry. At preselected timed intervals, the hydrocarbon feed is fed through the bypass loop to sweep the charge of catalyst slurry to the polymerization reactor.