Patent classifications
C08F4/65922
METHODS OF STABILIZING HYDROGENATION CATALYSTS
Provided is a hydrogenation catalyst solution comprising a solid catalyst precursor and an activator mixed in a solvent solution where propylene or another alpha-olefin or combination thereof is then added to this solution to prevent the formation of solids and stabilize the solution. The hydrogenation catalyst solution can then be combined with a polymerization catalyst such as Ziegler-Natta catalyst in a polymerization reactor so as to remove excess hydrogen from the reactor during a polymerization process. Hydrogen is eliminated by converting a portion of the olefins (propylene and ethylene) present into alkanes (propane and ethane).
Borate-activated metallocene catalysts
Catalyst system, the catalyst system comprising (i) at least one metallocene complex of formula (I), (I) wherein Mt1 is Hf, X is a sigma-donor ligand, R.sup.1, R.sup.2, R.sup.3 are the same or different from each other and can be hydrogen or a saturated linear or branched C.sub.1-C.sub.10 alkyl, whereby the alkyl group can optionally contain up to 2 heteroatoms belonging to groups 14-16 of the periodic table, or R.sup.1 and R.sup.2 or R.sup.2 and R.sup.3 can form a ring having 4 to 6 C-atoms and 1 to 3 double bonds, R.sup.4 and R.sup.5 are the same or different from each other and can be saturated linear or branched C.sub.1-C.sub.10 alkyl, C.sub.5-C.sub.10 aryl, C.sub.6-C.sub.20 alkylaryl or C.sub.6-C.sub.20 arylalkyl groups, which can optionally contain up to 2 heteroatoms belonging to groups 14-16 of the periodic table, n can be 1 to 5, Ar is a C.sub.6-C.sub.20-aryl or -heteroarylgroup, which can be unsubstituted or substituted by 1 to 5 linear or branched C.sub.1-C.sub.10 alkyl group(s), and (ii) a boron containing cocatalyst. ##STR00001##
OLEFIN POLYMERIZATION METHOD USING ANTISTATIC AGENT FOR METALLOCENE OLEFIN POLYMERIZATION PROCESS
Disclosed is an antistatic agent for a metallocene olefin polymerization process and a polymerization method using the same, by which discontinuity event due to sheeting or drooling occurring in the olefin polymerization process can be effectively reduced, enabling continuous operation for a long time, and the obtained final product can be applied to various applications including food contact use. The present disclosure includes an olefin polymerization method, which comprises forming a mixture in which an antistatic agent containing diglycerol oleate is mixed with a low molecular weight hydrocarbon, supplying the antistatic agent mixture and a metallocene-based catalyst composition comprising a metallocene catalyst and aluminoxane to two or more polymerization reactors, and polymerizing one or more alpha-olefins in the presence of the antistatic agent mixture and catalyst composition.
Catalyst Systems and Processes for Poly Alpha-Olefin Having High Vinylidene Content
A process for making a poly alpha-olefin (PAO) having a relatively high vinylidene content (or combined vinylidene and tri-substituted vinylene content) and a relatively low vinyl and/or di-substituted vinylene content, as well as a relatively low molecular weight. The process includes: contacting a feed containing a C.sub.2-C.sub.32 alpha-olefin with a catalyst system comprising activator and a bis-cyclopentadienyl metallocene compound, typically a cyclopentadienyl-benzindenyl group 4 transition metal compound.
Transition Metal Compound and Catalyst Composition Comprising Same
A novel transition metal compound and a catalyst composition including same are disclosed herein. In some embodiments, the transition metal compound is represented by formula 1 disclosed herein. In some embodiments, the catalyst composition comprises the transition metal compound represented by formula 1. The catalyst composition may be useful for preparing an olefin-based polymer having a high molecular weight in a low density region, and may be useful for preparing an olefin-based polymer having a low melting index (MI) in high temperature conditions and a high molecular weight.
Polyethylene and Its Chlorinated Polyethylene
There are provided a polyethylene capable of improving tensile strength while maintaining excellent processability and Mooney viscosity characteristics when preparing a chlorinated polyethylene compound by implementing a molecular structure having a low content of low molecular weight and a high content of high molecular weight, and a chlorinated polyethylene prepared using the same.
Transition Metal Compound for a Catalyst for Olefin Polymerization and Catalyst for Olefin Polymerization Comprising the Same
The present invention relates to a transition metal compound for a catalyst for olefin polymerization and to a catalyst for olefin polymerization comprising the same. Specifically, the present invention relates to a transition metal compound for an olefin polymerization catalyst in which an allyltrimethylsilane substituent is introduced into the cyclopentadienyl group and to a catalyst for olefin polymerization comprising the same.
Polyethylene and chlorinated polyethylene thereof
The polyethylene according to the present disclosure has a molecular structure having a narrow particle distribution and a low content of ultra-high molecular weight, so that a chlorinated polyethylene having excellent chlorination productivity and thermal stability may be prepared by reacting the polyethylene with chlorine. And, a PVC composition including the same with improved impact strength may also be prepared.
POLYMERIZATION OF ETHYLENE IN SOLUTION PROCESSES USING A ZIEGLER-NATTA CATALYST AND A HYDROGENATION CATALYST
The catalyst system includes a heterogeneous procatalyst and a hydrogenation procatalyst. The heterogeneous procatalyst includes a titanium species, an aluminum species, and a magnesium chloride component. The hydrogenation procatalyst has the formula Cp.sub.2TiX.sub.2, In formula Cp.sub.2TiX.sub.2, each Cp is a cyclopentadienyl substituted with at least one R.sup.1, wherein R.sup.1 is (C.sub.1-C.sub.10)alkyl; and each X is independently a halogen atom.
Methods and systems for olefin polymerization
Methods and systems for olefin polymerization are provided. The method for olefin polymerization can include flowing a catalyst through an injection nozzle and into a fluidized bed disposed within a reactor. The method can also include flowing a feed comprising one or more monomers, one or more inert fluids, or a combination thereof through the injection nozzle and into the fluidized bed. The feed can be at a temperature greater than ambient temperature. The method can also include contacting one or more olefins with the catalyst within the fluidized bed at conditions sufficient to produce a polyolefin.