Abstract: A dual reactor solution process gives high density polyethylene compositions containing a first ethylene copolymer and a second ethylene copolymer and which have good processability, toughness, and environmental stress crack resistance combined with good organoleptic properties. The polyethylene compositions are suitable for compression molding or injection molding applications and are particularly useful in the manufacture of caps and closures for bottles.

Abstract: A scavenger is used to indirectly control the ratio of polymer components in a polyethylene composition made using a combination catalyst comprising an inorganic chromium catalyst, and a group 4 single site catalyst.

Abstract: Resins suitable for rotomolded articles comprise a bimodal polyethylene copolymer comprising from 0.1 to 5 weight % of one or more C6-8 alpha olefins and the balance ethylene, comprising from 20 to 50 weight % of a higher molecular weight polymer component having an Mw greater than 120,000 and correspondingly from 80 to 50 weight % of a lower molecular weight polymer component having an Mw less than 100,000 having a density greater than 0.942 g/cc [but less than 0.965 g/cc] and a bent strip ESCR as determined by ASTM D 1693 in 100% Igepal® CO-630 (ethoxylated nonylphenols) for conditions A and B of greater than 1000 hours. The resulting articles have a very good balance of properties and significant ESCR.

Abstract: A scavenger is used to indirectly control the ratio of polymer components in a polyethylene composition made using a combination catalyst comprising an inorganic chromium catalyst, and a group 4 single site catalyst.

Abstract: The present invention provides a method to calibrate a NIR analyzer to measure monomer concentrations at one or more locations in a reactor system. The regression coefficients for the NIR analyzer are transferable between reactors using the same process (solution polymerization to solution polymerization) and may be used to control the reaction, or calibrate flow meters on line.

Abstract: A dual reactor solution polymerization process gives high density polyethylene compositions containing a first ethylene copolymer and a second ethylene copolymer and which have high dimensional stability, excellent processability as well as good organoleptic properties and reasonable stress cracking resistance. The polyethylene compositions are suitable for compression molding or injection molding applications and are useful, for example, in the manufacture of caps and closures for bottles, and for example, in bottles containing non-pressurized liquids.

Abstract: In the high pressure of polymerization of ethylene homopolymer or copolymers conditions in the reactor may become unstable leading to the decomposition (“decomp”) of the reaction mixture. Monitoring temperature excursions traveling through the reactor over close thermocouples (a roller) to detect changes in the mean temperature and the moving temperature front for a group of thermocouples detects conditions potentially leading to a decomp.

Abstract: A scavenger is used to indirectly control the ratio of polymer components in a polyethylene composition made using a combination catalyst comprising an inorganic chromium catalyst, and a group 4 single site catalyst.

Abstract: Resins suitable for rotomolded articles comprise a bimodal polyethylene copolymer comprising from 0.1 to 5 weight % of one or more C6-8 alpha olefins and the balance ethylene, comprising from 20 to 50 weight % of a higher molecular weight polymer component having an Mw greater than 120,000 and correspondingly from 80 to 50 weight % of a lower molecular weight polymer component having an Mw less than 100,000 having a density greater than 0.942 g/cc [but less than 0.965 g/cc] and a bent strip ESCR as determined by ASTM D 1693 in 100% Igepal® CO-630 (ethoxylated nonylphenols) for conditions A and B of greater than 1000 hours. The resulting articles have a very good balance of properties and significant ESCR.

Abstract: Carbon dioxide is used to control the ratio of polymer components in a polyethylene composition made using a combination catalyst comprising a chromium catalyst, a single site catalyst and one or more activators.

Abstract: A dual reactor solution process gives high density polyethylene compositions containing a first ethylene copolymer and a second ethylene copolymer and which have good processability, toughness, and environmental stress crack resistance combined with good organoleptic properties. The polyethylene compositions are suitable for compression molding or injection molding applications and are particularly useful in the manufacture of caps and closures for bottles.

Abstract: In the high pressure of polymerization of ethylene homopolymer or copolymers conditions in the reactor may become unstable leading to the decomposition (“decomp”) of the reaction mixture. Monitoring temperature excursions traveling through the reactor over close thermocouples (a roller) to detect changes in the mean temperature and the moving temperature front for a group of thermocouples detects conditions potentially leading to a decomp.

Abstract: The present invention provides a method to calibrate a NIR analyzer to measure monomer concentrations at one or more locations in a reactor system. The regression coefficients for the NIR analyzer are transferable between reactors using the same process (solution polymerization to solution polymerization) and may be used to control the reaction, or calibrate flow meters on line.

Abstract: The oligomerization of ethylene using a chromium catalyst having a heteroatomic ligand may be used to provide oligomerization products that are selective towards hexene and/or octene. However, such processes also typically produce some polymer as an undesirable by product. The present invention is directed towards improvements in the selective oligomerization of ethylene.

Abstract: Carbon dioxide is used to control the ratio of polymer components in a polyethylene composition made using a combination catalyst comprising a chromium catalyst, a single site catalyst and one or more activators.

Abstract: In a solution polymerization process the increase in gel content in the solution at one or more locations may be detected by monitoring the structure of a spectrum obtained by analyzing the reaction at said one or more locations using a spectrometer selected from the group consisting of infrared spectrometers, near infrared spectrometers and Raman spectrometers.

Abstract: In a solution polymerization process the increase in gel content in the solution at one or more locations may be detected by monitoring the structure of a spectrum obtained by analyzing the reaction at said one or more locations using a spectrometer selected from the group consisting of infrared spectrometers, near infrared spectrometers and Raman spectrometers.