Abstract: A single-site olefin polymerization catalyst is described. The catalyst comprises an activator and an inorganic compound comprising iron and a tridentate N-(2-ethylamino)-2-pyridylmethanimino or N,N-bis(2-pyridylmethyl)amino ligand. The late transition metal catalyst is active in olefin polymerization.

Abstract: An olefin polymerization catalyst system and method of making it are disclosed. The catalyst system comprises an activator and an organometallic complex. The complex comprises a Group 3 to 10 transition or lanthanide metal, M, and at least one anionic 1,3-diboretanyl ligand that is bonded to M. Molecular modeling results indicate that catalysts from organometallic complexes that incorporate anionic 1,3-diboretanyl ligands will rival the performance of traditional metallocenes.

Abstract: A single-site olefin polymerization catalyst and method of making it are disclosed. The catalyst comprises an activator and an organometallic complex. The complex comprises a Group 3 to 10 transition metal, M, and at least one anionic heterocyclobutenyl ligand that is bonded to M. Molecular modeling results indicate that single-site catalysts based on anionic heterocyclobutenyl ligands will have advantages compared with the performance of catalysts based on cyclopentadienyl and substituted cyclopentadienyl ligands.

Abstract: Single-site catalysts useful for polymerizing olefins are disclosed. The catalysts incorporate a Group 3 to 10 transition, lanthanide, or actinide metal and an anionic thiopyran dioxide ligand. Because a wide variety of thiopyran dioxides are easy to prepare from commercially available starting materials, the invention enables the preparation of a new family of single-site catalysts.

Abstract: A process for making ethylene copolymers is disclosed. Ethylene copolymerizes with an &agr;-olefin in the presence of a catalyst system comprising an activator and a silica-supported, bridged indenoindolyl metal complex having “open architecture.” The supported complex incorporates comonomers with exceptional efficiency, and the process gives ethylene copolymers having high molecular weights (Mw>100K) and very low densities (<0.910 g/cm3). Open architecture catalysts that include bridging through the indolyl nitrogen of the indenoindolyl framework are also described.

Abstract: The oxidation of a polymer is inhibited by adding to the polymer about 0.

Abstract: A catalyst system useful for polymerizing olefins is disclosed. The catalyst system comprises an activator and a complex that incorporates a Group 3 to 10 transition metal and at least one chelating dianionic bis(allyl) or bis(benzyl) ligand. The ligands are often easy to make, and they are readily incorporated into transition metal complexes. By modifying the structure of the dianionic ligand, polyolefin makers can control comonomer incorporation, catalyst activity, and polymer properties.

Abstract: A propylene polymerization process is disclosed. The process gives polypropylene having isotactic and atactic stereoblock sequences. The process is performed in the presence of a non-bridged bisindenoindol-based single-site catalyst. The polypropylene produced has an isotactic pentad (mmmm) content within the range of about 10 mole % to about 70 mole %.

Abstract: A catalyst system useful for polymerizing olefins is disclosed. The catalyst system comprises an activator and a complex that incorporates a Group 3 to 10 transition metal and at least one chelating dianionic bis(allyl) or bis(benzyl) ligand. The ligands are often easy to make, and they are readily incorporated into transition metal complexes. By modifying the structure of the dianionic ligand, polyolefin makers can control comonomer incorporation, catalyst activity, and polymer properties.

Abstract: A single-site olefin polymerization catalyst and method of making it are disclosed. The catalyst comprises an activator and an organometallic complex. The complex comprises a Group 3 to 10 transition or lanthanide metal, M, and at least one chelating N-oxide ligand that is bonded to M. Molecular modeling results indicate that single-site catalysts based on certain chelating N-oxide ligands (e.g., 2-hydroxypyridine) will rival the performance of catalysts based on cyclopentadienyl and substituted cyclopentadienyl ligands.

Abstract: Disclosed is a solution that comprises (A) a solvent; (B) about 0.001 to about 20 wt % of a terpolymer that comprises the condensation reaction product of (1) an aromatic compound that contains a benzene or naphthalene ring substituted with the group OR or SR, where R is hydrogen, alkyl from C1 to C15, or aryl, alkaryl, or aralkyl from C6 to C15; (2) about 0.1 to about 10 moles of a carbonyl compound per mole of said aromatic compound; and (3) about 0.1 to about 10 moles of a thiourea per mole of said aromatic compound (C) about 1 to about 5 wt % of a base; (D) about 0.1 wt % to saturation of a salt; and (E) 0 to about 20 wt % of an alcohol. Also disclosed is a method of making the terpolymer in the absence of an acid catalyst and a method of inhibiting the formation of scale on reactor components in contact with polymerizing vinyl chloride monomer.

Abstract: Single-site catalyst systems useful for polymerizing olefins are disclosed. The catalyst systems comprise an organometallic complex and an activator. The complex includes a Group 3-10 transition metal, M, and at least one indenoindolyl ligand that is pi-bonded to M. The activator is a reaction product of an alkylaluminum compound and an organoboronic acid. Catalyst systems of the invention significantly outperform known catalyst systems that employ a metallocene complex and similar aluminoboronate activators.

Abstract: A single-site olefin polymerization catalyst and method of making it are disclosed. The catalyst comprises an activator and an organometallic complex. The complex comprises a Group 3 to 10 transition or lanthanide metal, M, and at least one chelating N-oxide ligand that is bonded to M. Molecular modeling results indicate that single-site catalysts based on certain chelating N-oxide ligands (e.g., 2-hydroxypyridine) will rival the performance of catalysts based on cyclopentadienyl and substituted cyclopentadienyl ligands.

Abstract: A propylene polymerization process is disclosed. The process gives polypropylene having isotactic and atactic stereoblock sequences. The process is performed in the presence of a non-bridged bisindenoindol-based single-site catalyst. The polypropylene produced has an isotactic pentad (mmmm) content within the range of about 10 mole % to about 70 mole %.

Abstract: Single-site catalysts useful for polymerizing olefins are disclosed. The catalysts incorporate a Group 3 to 10 transition, lanthanide, or actinide metal and an anionic thiopyran dioxide ligand. Because a wide variety of thiopyran dioxides are easy to prepare from commercially available starting materials, the invention enables the preparation of a new family of single-site catalysts.

Abstract: Disclosed is a catalyst composition and a method of polymerizing vinyl chloride using it. The catalyst composition is a mixture of a vanadyl (V) catalyst having the formula and about 0.5 to about 15 moles of an alkyl aluminum cocatalyst having the formula (R′)mAl(X′)3−m per mole of said catalyst, where R is a group containing 1 to 14 carbon atoms, each X is independently selected from halogen or OR, each R′ is independently selected from alkyl from C1 to C10, each X′ is independently selected from halogen, R1 is alkyl from C1 to C10, haloalkyl from C1 to C10, alkoxyalkyl where each alkyl group is independently selected from C1 to C10, or aryl from C6 to C14, m is 1 or 2, and n is 1 to 100. Also disclosed is a method of polymerizing vinyl chloride comonomer using this catalyst.

Abstract: A bimetallic olefin polymerization catalyst is described. The catalyst comprises an organometallic compound, and optionally, an activator. The organometallic compound comprises a Group 3-5 transition or lanthanide metal, M1, a Group 6-10 transition metal, M2, and a multidentate ligand characterized by a cyclopentadienyl group that is covalently linked to two Group 15 atoms, wherein the cyclopentadienyl group is &pgr;-bonded to M1 and the two Group 15 atoms are coordinated to M2. The bimetallic catalyst is useful for producing copolymers from ethylene without using a co-monomer by oligomerizing ethylene and simultaneously polymerizing ethylene and the co-formed oligomer.

Abstract: Novel polymer stabilizers are disclosed. The novel stabilizers have the general formula (R)qSn-(MR″-OCH2-R′CH]m-OT)4-q, P-[(OCH2-R′CH)mOT]3′ wherein M is O or S and R″is (CH2)pCO-, CO-(CH3)p, or CO(CH2)p-. About 0.005 to about 65 phr of the stabilizer can be used in a polymer having a halogen-containing repeating unit, such as poly(vinyl chloride), to reduce yellowing of an article made from the polymer after the article has been exposed to gamma radiation.

Abstract: Catalyst systems useful for olefin polymerization are disclosed. The catalyst systems include an activator and an organometallic complex. The complex, which incorporates at least one Group 3-10 transition or lanthanide metal, is uniquely prepared from an indenoindolyl dianion or its synthetic equivalent. A diverse array of monomeric, dimeric, polymeric, or zwitterionic complexes are available from the dianion or its equivalent.

Abstract: A method of preparing a sterile article is disclosed. A polymer having a halogen-containing repeating unit is prepared that contains about 0.