Methods and apparatus for the preparation and use of a substrate having an array of diverse materials in predefined regions thereon. A substrate having an array of diverse materials thereon is generally prepared by delivering components of materials to predefined regions on a substrate, and simultaneously reacting the components to form at least two materials. Materials which can be prepared using the methods and apparatus of the present invention include, for example, covalent network solids, ionic solids and molecular solids. More particularly, materials which can be prepared using the methods and apparatus of the present invention include, for example, inorganic materials, intermetallic materials, metal alloys, ceramic materials, organic materials, organometallic materials, non-biological organic polymers, composite materials (e.g., inorganic composites, organic composites, or combinations thereof), etc. Once prepared, these materials can be screened for useful properties including, for example, electrical, thermal, mechanical, morphological, optical, magnetic, chemical, or other properties. Thus, the present invention provides methods for the parallel synthesis and analysis of novel materials having useful properties.

Combinatorial synthesis of novel materials

The present invention relates, inter alia, to methodologies for the synthesis, screening and characterization of organometallic compounds and catalysts (e.g., homogeneous catalysts). The methods of the present invention provide for the combinatorial synthesis, screening and characterization of libraries of supported and unsupported organometallic compounds and catalysts (e.g., homogeneous catalysts). The methods of the present invention can be applied to the preparation and screening of large numbers of organometallic compounds which can be used not only as catalysts (e.g., homogeneous catalysts), but also as additives and therapeutic agents.

Combinatorial Synthesis and Analysis of Organometallic Compounds and Catalysts

This invention is generally directed toward a supported catalyst system useful for polymerizing olefins. The method for supporting the catalyst system of the invention provides for a supported metallocene catalyst and alumoxane activator which when utilized in a polymerization process substantially reduces the reactor fouling and sheeting.

Polymerization catalyst systems, their production and use

Catalyst compositions and methods, useful in polymerization processes, utilizing at least two metal compounds are disclosed. At least one of the metal compounds is a Group 15 containing metal compound and the other metal compound is preferably a bulky ligand metallocene-type catalyst. The invention also discloses a new polyolefin, generally polyethylene, particularly a multimodal polymer and more specifically, a bimodal polymer, and its use in various end-use applications such as film, molding and pipe.

Catalyst composition, method of polymerization, and polymer therefrom

The disclosed ethylene polymer compositions have et least one homogeneously branched substantially linear ethylene/α-olefin interpolymer and at least one heterogeneously branched ethylene polymer. The homogeneously branched linear or substantially linear ethylene/α-olefin interpolymer has a density from about 0.88 to about 0.935 g/cm3 and a slope of strain hardening coefficient greater than or equal to about 1.3. Films made from such formulated compositions have surprisingly good impact and tensile properties, and have an especially good combination of modulus and toughness.

Fabricated articles made from ethylene polymer blends

A process is provided for producing a bimodal ethylene polymer blend comprising contacting in a first gas phase, fluidized bed reaction zone under polymerization conditions, a gaseous monomeric composition comprising a major proportion of ethylene and, optionally, hydrogen, with a Ziegler-Natta catalyst, the hydrogen/ethylene molar ratio (H₂/C₂ ratio) being no higher than about 0.3 and the ethylene partial pressure being no higher than about 100 psia, to produce a relatively high molecular weight (HMW) polymer associated with catalyst particles, transferring the HMW polymer associated with catalyst particles to a second gas phase, fluidized bed reaction zone into which is also fed hydrogen and a gaseous monomeric composition comprising a major proportion of ethylene, under polymerization conditions including an H₂/C₂ ratio of at least about 0.9 and at least about 8.0 times that in the first reaction zone, and an ethylene partial pressure of at least 1.7 times that in said first reaction zone, to produce a low molecular weight (LMW) polymer deposited on and within the voids of the HMW polymer/catalyst particles, the resulting bimodal polymer blend obtained from the second reaction zone having a fraction of HMW polymer of at least about 0.35.

Process for producing bimodal ethylene polymers in tandem reactors

A blend for blown film which exhibits improved MD/TD tear balance. The blend is a bimodal molecular weight ethylene resin containing two fractions of different molecular weight. The weight fraction of a higher molecular weight component of the blend is about 0.35 to 0.75.

Producing blown film and blends from bimodal high density high molecular weight film resin using magnesium oxide-supported Ziegler catalyst

A catalyst composition for copolymerizing ethylene with alpha-olefins is prepared by supporting a magnesium compound and a titanium compound on a solid, inert porous carrier, and activating the precursor with a mixture of dimethylaluminum chloride and a trialkylaluminum compound. Products with a bimodal molecular weight distribution are produced which are free of alpha-olefin oligomers.

Binary cocatalyst compositions for activating heterogeneous polymerization catalysts

A process is provided for producing a bimodal ethylene polymer blend comprising contacting in a first gas phase, fluidized bed reaction zone under polymerization conditions, a gaseous monomeric composition comprising a major proportion of ethylene and, optionally, hydrogen, with a non-prereduced supported titanium/magnesium precursor catalyst as primary catalyst component in combination with a hydrocarbyl aluminium reducing co-catalyst, the hydrogen/ethylene molar ratio (H₂/C₂ ratio) being no higher than about 0.3 and the ethylene partial pressure being no higher than about 100 psia, to produce a relatively high molecular weight (HMW) polymer associated with catalyst particles, transferring the HMW/catalyst particles to a second gas phase, fluidized bed reaction zone into which is also fed hydrogen and a gaseous monomeric composition comprising a major proportion of ethylene, under polymerization conditions including an H₂/C₂ ratio of at least about 0.9 and at least about 8.0 times that in the first reaction zone, and an ethylene partial pressure of at least 1.7 times that in said first reaction zone, to produce a low molecular weight (LMW) polymer deposited on and within the voids of the HMW polymer/catalyst particles, the resulting bimodal polymer blend obtained from the second reaction zone having a fraction of HMW polymer of at least about 0.35.

Production of bimodal ethylene polymers in tandem reactors

A process for maintaining the electrostatic charges substantially at neutral levels thereby reducing or avoiding sheeting in a fluid bed gas olefin polymerization reactor.

Ahmed Hussein Ali

Papers

Process for producing bimodal ethylene polymers in tandem reactors

Producing blown film and blends from bimodal high density high molecular weight film resin using magnesium oxide-supported Ziegler catalyst

Binary cocatalyst compositions for activating heterogeneous polymerization catalysts

Production of bimodal ethylene polymers in tandem reactors

Static control with TEOS