Silica composites and supported chromium catalysts having a bulk density of 0.08 to 0.4 g/mL, a total pore volume of 0.4 to 2.5 mL/g, a BET surface area of 175 to 375 m.sup.2/g, and a peak pore diameter of 10 to 80 nm are disclosed herein. These silica composites and supported chromium catalysts can be formed by combining two silica components. The first silica component can be irregularly shaped, such as fumed silica, and the second silica component can be a colloidal silica or a silicon-containing compound, and the second silica component can act as a glue to bind the silica composite together.

Silica composites and supported chromium catalysts having a bulk density of 0.08 to 0.4 g/mL, a total pore volume of 0.4 to 2.5 mL/g, a BET surface area of 175 to 375 m.sup.2/g, and a peak pore diameter of 10 to 80 nm are disclosed herein. These silica composites and supported chromium catalysts can be formed by combining two silica components. The first silica component can be irregularly shaped, such as fumed silica, and the second silica component can be a colloidal silica or a silicon-containing compound, and the second silica component can act as a glue to bind the silica composite together.

An object of the present invention is to provide a multi-component polar olefin copolymer which has sufficiently improved solvent solubility without impairing mechanical properties and the like. The present invention relates to a multi-component polar olefin copolymer containing: one kind of unit of nonpolar monomer (X1) that is ethylene or an α-olefin having 3 to 10 carbon atoms; one or two or more kinds of units of polar monomers (formula (1), Z1); and structural unit(s) of one or two or more kinds of units of nonpolar monomers (X2) that are different from the above X1 and/or one or two or more kinds of units of polar monomers (formula (2), Z2):
H.sub.2C═CH—COOQT1  (1)
H.sub.2C═CH-T2  (2).

Processes of polymerizing olefin monomers. The process comprising reacting ethylene and optionally one or more olefin monomers in the presence of a catalyst system, wherein the catalyst system comprises: an activator; hydrocarbyl-modified methylaluminoxane having less than 25 mole percent trihydrocarbyl aluminum compounds AlR.sup.A1R.sup.B1R.sup.C1 based on the total moles of aluminum, where R.sup.A1, R.sup.B1, and R.sup.C1 are independently linear (C.sub.1-C.sub.40)alkyl, branched (C.sub.1-C.sub.40)alkyl, or (C.sub.6-C.sub.40)aryl; and one or more metal-ligand complexes according to formula (1):

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A production method for a cyclic olefin copolymer which is capable of efficiently producing a cyclic olefin copolymer by copolymerizing monomers including a norbornene monomer and ethylene while suppressing the formation of a polyethylene-like impurity, and a catalyst composition for the copolymerization of a norbornene monomer and ethylene. Monomers including a norbornene monomer and ethylene are polymerized in the presence of a metal-containing catalyst, and the metal-containing catalyst has a structure in which a nitrogen atom is bonded to a transition metal of Group 4 of the periodic table and an atom of Group 15 of the periodic table.

A method of producing bimodal ethylene-based polymer includes reacting ethylene monomer and C.sub.3-C.sub.12 α-olefin comonomer in the presence of a first catalyst in an agitated reactor to produce a first polymer fraction, and outputting effluent from the agitated reactor. A second catalyst is added to the effluent downstream of the agitated reactor and upstream from a non-agitated reactor, the second catalyst facilitates production of a second polymer fraction having a density and melt index (I.sub.2) different from the first polymer fraction. The second catalyst and effluent are mixed in at least one mixer. The second catalyst, second polymer fraction, and the first polymer fraction are passed to the non-agitated reactor; and additional ethylene monomer, additional C.sub.3-C.sub.12 α-olefin comonomer, and solvent are passed to the non-agitated reactor to produce more second polymer fraction and thereby the bimodal ethylene-based polymer.

The system provides new methods and processes for the reaction of polymeric/oligomeric substrates with reactants comprising alkyne/alkene and/or protic nucleophilic moieties to afford functionalized polymeric/oligomeric products through the utilization of homogenous and/or heterogenous gold catalysis. More specifically, the system provides routes for reaction of polymeric/oligomeric substrates comprising varying degrees of aromatic character with alkyne/alkene bearing molecules to afford a functionalized polymeric/oligomeric product. The system additionally provides pathways wherein the inverse methodology is realized, providing functionalized materials from the reaction of polymeric substrates bearing alkyne/alkene moieties with aromatic and/or protic nucleophilic reagents. Furthermore, in a tangential methodology, the system affords functionalized polymeric materials from the reaction of polymeric substrates bearing protic nucleophilic substituents with alkyne/alkene containing molecules. The system provides pathways for the facile modification of commodity polymer materials in order to produce value-added materials utilizing current polymer infrastructure, commodity polymer feedstocks, and post-consumer plastic waste.

The present disclosure discloses a catalyst composition for polymerization of an α-olefin and preparation and use thereof. The catalyst composition comprises boron trifluoride and at least one protic cocatalyst; the protic cocatalyst has a structural formula of X—(CH.sub.2).sub.n—OH, where n is an integer selected from 1 to 10; X is selected from nitro, halogen, cyano, sulfonic acid group, aldehyde group, acyl, carboxyl and amino. The catalyst can be used in production of a poly(α-olefin) synthetic base oil, and is particularly suitable for a low viscosity poly(α-olefin) synthetic base oil with high selectivity of the target product.

A modified Ziegler-Natta procatalyst that is a product mixture of modifying an initial Ziegler-Natta procatalyst with a molecular (pro)catalyst, and optionally an activator, the modifying occurring before activating the modified Ziegler-Natta procatalyst with an activator and before contacting the modified Ziegler-Natta procatalyst with a polymerizable olefin. Also, a modified catalyst system prepared therefrom, methods of preparing the modified Ziegler-Natta procatalyst and the modified catalyst system, a method of polymerizing an olefin using the modified catalyst system, and a polyolefin product made thereby.

Silica composites and supported chromium catalysts having a bulk density of 0.08 to 0.4 g/mL, a total pore volume of 0.4 to 2.5 mL/g, a BET surface area of 175 to 375 m.sup.2/g, and a peak pore diameter of 10 to 80 nm are disclosed herein. These silica composites and supported chromium catalysts can be formed by combining two silica components. The first silica component can be irregularly shaped, such as fumed silica, and the second silica component can be a colloidal silica or a silicon-containing compound, and the second silica component can act as a glue to bind the silica composite together.