Abstract: An ethylene oligomerization catalyst which contains a bridged diphosphine ligand having the formula (R1)m(X1)nP1-bridge-P2(R2)X2 wherein R1 and R2 are independently selected from the group consisting of hydrocarbyl and heterohydrocarbyl; X1 is selected from the group consisting of halogen, hydrocarbyl and heterohydrocarbyl; m is 1 or 2; n is 0 or 1; m+n=2; bridge is a divalent bridging group bonded to P1 and P2; and X2 is halogen. The present ligands differ from prior diphosphine ligands used in olefin oligomerization processes in that at least one halide substituent is directly bonded to at least one P atom of the ligand.

Abstract: Olefin polymerization is carried out with a supported phosphinimine catalyst which has been treated with a long chain substituted amine compound.

Abstract: Olefin polymerization is carried out with a supported phosphinimine catalyst which has been treated with a long chain substituted amine compound.

Abstract: Olefin polymerization is carried out with a supported phosphinimine catalyst which has been treated with a long chain substituted amine compound.

Abstract: Olefin polymerization is carried out with a supported phosphinimine catalyst which has been treated with a long chain substituted amine compound.

Abstract: Olefin polymerization is carried out with a supported phosphinimine catalyst which has been treated with a long chain substituted amine compound.

Abstract: Polyethylene films having a good balance of optical and mechanical properties are disclosed. The films are derived from ethylene copolymer compositions made with a suitably substituted phosphinimine catalyst. The ethylene copolymers have very narrow molecular weight distributions and broadened comonomer distributions.

Abstract: This invention enables the “bulk” oligomerization of ethylene (i.e. the oligomerization of ethylene in the presence of the oligomer product) using a catalyst system comprising 1) a very low concentration of a chromium catalyst and 2) a three part activator. The chromium catalyst contains a diphosphine ligand, preferably a so called P—N—P ligand. The activator includes an aluminoxane, trimethyl aluminum, and triethyl aluminum.

Abstract: Ethylene copolymers having a relatively high melt flow ratio and a multimodal profile in a temperature rising elution fractionation (TREF) plot are disclosed. The copolymers can be made into film having good dart impact values and good stiffness properties under decreased extruder pressures.

Abstract: Ethylene copolymers having a relatively high melt flow ratio and a multimodal profile in a temperature rising elution fractionation (TREF) plot are disclosed. The copolymers can be made into film having good dart impact values and good stiffness properties under decreased extruder pressures.

Abstract: Compounds 1,3,4-(SiMe3)(C6F5)(alkyl)C5H3 are made using a simplified synthetic strategy which is readily scalable. On reaction with a suitable transition metal species, a 1,3,4-(SiMe3)(C6F5)(alkyl)C5H3 molecule provides an organotransition metal complex comprising a 1,2-(C6F5)(alkyl) substituted cyclopentadienyl ligand, which is active toward olefin polymerization.

Abstract: Olefin polymerization is carried out with a supported phosphinimine catalyst which has been treated with a long chain substituted amine compound.

Abstract: The oligomerization of ethylene using a chromium catalyst and an aluminoxane activator is well known. The undesired formation of polyethylene as a by-product is also known to occur during prior oligomerization processes. We have discovered that the use of an aluminoxane that is prepared by non-hydrolytic means provides a highly productive activator (co-catalyst) for ethylene oligomerization and mitigates the undesired formation of by-product polyethylene.

Abstract: Polyethylene films having a good balance of optical and mechanical properties are disclosed. The films are derived from ethylene copolymer compositions made with a suitably substituted phosphinimine catalyst. The ethylene copolymers have very narrow molecular weight distributions and broadened comonomer distributions.

Abstract: A new P—N—P ligand is useful in ethylene oligomerizations. In combination with i) a source of chromium and ii) an activator such as methylalumoxane; the ligand of this invention may be used to prepare an oligomer product that contains a mixture of hexenes and octenes. The hexenes and octenes produced with this ligand contain very low levels of internal olefins when produced under preferred reaction conditions.

Abstract: A new P-N-P ligand in which each phosphorus atom is bonded to two ortho-fluorine substituted phenyl groups is useful in ethylene oligomerizations. In combination with i) a source of chromium and ii) an activator such as methalumoxane; the ligand of this invention may be used to prepare an oligomer product that contains a mixture of hexenes and octenes. The hexenes and octenes produced with this ligand contain very low levels of internal olefins when produced under preferred reaction conditions.

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: The oligomerization of ethylene using a chromium catalyst having a bridged diphosphine ligand can produce a selective product distribution (to predominantly hexene or predominantly octene/hexene) when activated with an aluminoxane. The oligomerization reaction also produces polymer by product—particularly when the aluminoxane is provided in a non-aromatic solvent. The present invention mitigates this problem.

Abstract: An ethylene oligomerization catalyst which contains a bridged diphosphine ligand having the formula (R1)m(X1)nP1-bridge-P2(R2)X2 wherein R1 and R2 are independently selected from the group consisting of hydrocarbyl and heterohydrocarbyl; X1 is selected from the group consisting of halogen, hydrocarbyl and heterohydrocarbyl; m is 1 or 2; n is 0 or 1; m+n=2; bridge is a divalent bridging group bonded to P1 and P2; and X2 is halogen. The present ligands differ from prior diphosphine ligands used in olefin oligomerization processes in that at least one halide substituent is directly bonded to at least one P atom of the ligand.

Abstract: The oligomerization of ethylene using a chromium catalyst having a phosphorus-nitrogen-phosphorus (“P—N—P”) ligand is typically activated with an aluminoxane. The addition of an alkyl zinc, particularly diethyl zinc, has been fund to improve the productivity of certain oligomerization reactions. In particular, the addition of diethyl zinc to an oligomerization reaction that is activated by methylaluminoxane (MAO) improves the productivity of the reaction.