摘要:
This invention relates to catalyst compositions, methods, and polymers encompassing a Group 4 metallocene with bridging θ5-cyclopentadienyl-type ligands, in combination with a cocatalyst and an activator-support. The compositions and methods disclosed herein provide ethylene polymers with low levels of long chain branching.
摘要:
This invention relates to catalyst compositions, methods, and polymers encompassing a Group 4 metallocene with bridging η5-cyclopentadienyl-type ligands, in combination with a cocatalyst and an activator-support. The compositions and methods disclosed herein provide ethylene polymers with low levels of long chain branching.
摘要:
This invention relates to catalyst compositions, methods, and polymers encompassing a Group 4 metallocene with bridging η5-cyclopentadienyl-type ligands, in combination with a cocatalyst and an activator-support. The compositions and methods disclosed herein provide ethylene polymers with low levels of long chain branching.
摘要:
This invention relates to catalyst compositions, methods, and polymers encompassing at least one first Group 4 metallocene compound comprising bridging η5-cyclopentadienyl-type ligands, in combination with at least one second Group 4 metallocene with non-bridging η5-cyclopentadienyl-type ligands, typically in combination with at least one cocatalyst, and at least one activator. The compositions and methods disclosed herein provide ethylene polymers with a bimodal molecular weight distribution.
摘要:
Multiple components are selected, conveyed, and measured in a polymerization system. A control system adjusts the system variables to the desired values. Portions of the components can be fed to a pre-contactor before introduction into the polymerization reactor. The catalyst component concentrations and residence times are tightly controlled in the pre-contactor to affect product properties. The pre-contactor can be a single or multiple combinations of a CSTR or plug flow pre-contactors.