Abstract:
The invention relates to novel bridged biphosphole ligands according to the general formula: 1 where R2, R3, R4 are chosen from hydrogen, alkyl, aryl or silyl, R1 is chosen from hydrogen, alkyl, aryl or halogen, R1 possibly being replaced with a direct bond between the two phosphorus atoms and T is a divalent group. The invention also relates to metallocenes obtained from these ligands. These metallocenes are useful as catalytic components for the polymerization of olefins.
Abstract:
A microencapsulated catalyst is prepared by dissolving or dispersing a catalyst in a first phase (for example an organic phase), dispersing the first phase in a second, continuous phase (for example an aqueous phase) to form an emulsion, reacting one or more microcapsule wall-forming materials at the interface between the dispersed first phase and the continuous second phase to form a microcapsule polymer shell encapsulating the dispersed first phase core and optionally recovering the microcapsules from the continuous phase. The catalyst is preferably a transition metal catalyst and the encapsulated catalyst may be used for conventional catalysed reactions. The encapsulated catalyst may recovered from the reaction medium and re-cycled.
Abstract:
A discrete polyolefin catalyst activator is disclosed. A salient feature of invention borate-based activators is that at least one of the ligands on the borate non-coordinating anion (NCA) comprises a fluorinated aryl group linked to the boron atom through an acetylenic group appropriate pairing of invention activators with olefin polymerization. Catalyst precursors yield increased catalytic activity. Polymerization results are disclosed.
Abstract:
The present invention relates to a catalyst for homo-polymerization or co-polymerization of ethylene, or more particularly to a solid complex titanium catalyst for homo-polymerization or co-polymerization of ethylene. The catalyst may be produced by preparing a magnesium solution by contact-reacting a magnesium halide compound with an alcohol. Reacting the solution with an ester compound and a boron compound. Then reacting the solution with a mixture of a titanium compound and a silicon compound.
Abstract:
Process for preparing an olefin polymerisation catalyst component in the form of particles having a predetermined size range, said process comprising the steps of a) preparing a solution of a complex of a Group 2 metal and an electron donor by reacting a compound of said metal with said electron donor or a precursor thereof in an organic liquid reaction medium; b) adding said solution of said complex to at least one compound of a transition material to produce an emulsion, the dispersed phase of which contains more than 50 mol % of the Group 2 metal in said complex; c) agitating the emulsion, optionally in the presence of an emulsion stabilizer, in order to maintain the droplets of said dispersed phase within the average size range 5 to 200 m; d) solidifying said droplets of the dispersed phase; and e) recovering the solidified particles of the olefin polymerisation catalyst component, wherein a turbulence minimizing agent (TMA) is added to the reaction mixture before solidifying said droplets of the dispersed phase, said TAM being inert and soluble in the reaction mixture under the reaction conditions.
Abstract:
A modified aluminum oxy compound (A) obtained by reacting an aluminum oxy compound (a), water (b) and a compound having a hydroxyl group (c); a polymerization catalyst component comprising the modified aluminum oxy compound; a polymerization catalyst obtained by contacting said modified aluminum oxy compound (A), a transition metal compound (B) and optionally an organoaluminum compound (C) and a specified boron compound; and a process for producing an olefin polymer or an alkenyl aromatic hydrocarbon polymer with the polymerization catalyst.
Abstract:
Group 4 metal complexes useful as addition polymerization catalysts of the formula: 1 G1 is a group containing from 1 to 40 atoms not counting hydrogen; T is a divalent bridging group of from 10 to 30 atoms not counting hydrogen, selected from mono- or di-aryl-substituted methylene or silylene groups or mono- or di-heteroaryl-substituted methylene or silylene groups, wherein at least one such aryl- or heteroaryl-substituent is substituted in one or both ortho-positions with a secondary or tertiary alkyl-group, a secondary or tertiary heteroalkyl group, a cycloalkyl group, or a heterocycloalkyl group, G2 is a C6-20 heteroaryl group containing Lewis base functionality, M is the Group 4 metal, Xnullnull is an anionic, neutral or dianionic ligand group, xnullnull is a number from 0 to 5, and bonds, optional bonds and electron donative interactions are represented by lines, dotted lines and arrows respectively.
Abstract:
A solid catalyst for asymmetric hydrogenation reactions is disclosed comprising a chiral cationic metal-ligand complex immobilised on a mesoporous alumino-silicate support. The catalyst is formed by ion exchange with the acid sites of the support. The catalyst is reusable, and maintains its activity after use.
Abstract:
Metal-ligand complexes that are useful as precursors to catalysts for the polymerization of olefins are provided. Certain of the catalysts are particularly effective at polymerizing ethylene and styrene into copolymers having novel properties, including a low molecular weight and close comparison between vinyl and methyl end groups.
Abstract:
A subject of the present invention is new compounds having a lanthanide and having a tridentate ligand, a process for their preparation and their use in particular as polymerization catalysts.