A photocatalyst can be regenerated with increasing efficiency, turnover number and turnover frequency in the presence of air by irradiating the photocatalyst with a first range of wavelengths of light that excite the photocatalyst to an intermediate and irradiating the intermediate with a second range of wavelengths of light that turns the intermediate to the photocatalyst.

The present disclosure provides catalyst compounds including a nonsymmetric bridged amine bis(phenolate), catalyst systems including such, and uses thereof. Catalyst compounds, catalyst systems, and processes of the present disclosure can provide high comonomer content and high molecular weight polymers having narrow Mw/Mn values, contributing to good processability for the polymer itself and for the polymer used in a composition.

A system and method for producing 1-butene and ultra-high-molecular-weight polyethylene (UHMWPE), including feeding a catalyst, an antifouling co-catalyst, and ethylene to a reactor, and dimerizing ethylene into 1-butene and polymerizing a relatively small portion of the ethylene into UHMWPE. A product slurry including 1-butene and UHMWPE is discharged from reactor and UHMWPE is removed from the product slurry as a coproduct of the product 1-butene. The coproduct UHMWPE may be a byproduct that is a relatively small amount of the product slurry. The quantity of UHMWPE produced may be small in comparison to the quantity of 1-butene produced.

In one aspect, oligomeric and polymeric species are described herein exhibiting new architectures and associated properties. In some embodiments, such species are synthesized by oligomerization or polymerization of diene monomer via cycloaddition in the presence of a transition metal complex. Oligomers described herein, for example, comprise cyclobutane units in the oligomer backbone. Similarly, a polymers described herein comprise cyclobutane units in the polymer backbone.

A system and method for producing 1-butene and ultra-high-molecular-weight polyethylene (UHMWPE), including feeding a catalyst, an antifouling co-catalyst, and ethylene to a reactor, and dimerizing ethylene into 1-butene and polymerizing a relatively small portion of the ethylene into UHMWPE. A product slurry including 1-butene and UHMWPE is discharged from reactor and UHMWPE is removed from the product slurry as a coproduct of the product 1-butene. The coproduct UHMWPE may be a byproduct that is a relatively small amount of the product slurry. The quantity of UHMWPE produced may be small in comparison to the quantity of 1-butene produced.

The present disclosure provides catalyst compounds including a nonsymmetric bridged amine bis(phenolate), catalyst systems including such, and uses thereof. Catalyst compounds, catalyst systems, and processes of the present disclosure can provide high comonomer content and high molecular weight polymers having narrow Mw/Mn values, contributing to good processability for the polymer itself and for the polymer used in a composition.

Disclosed herein are mixed catalyst systems including iron-containing catalyst compounds having a carbene ligand and another catalyst compound, as well as at least one activator. The iron-containing catalyst compounds can be asymmetric, while the other catalyst compound can be symmetric. In some embodiments, the other catalyst compound can be an iron-containing catalyst with a bisiminopyridyl ligand, which does not typically incorporate comonomers in copolymer synthesis. Processes for production of an ethylene alpha-olefin copolymers using these mixed catalyst systems are also disclosed. Ethylene-alpha-olefin copolymers so formed can have at least a portion of their alpha-olefin comonomer distribution increasing with increasing molecular weight, indication orthogonal compositional distribution.

In one aspect, oligomeric and polymeric species are described herein exhibiting new architectures and associated properties. In some embodiments, such species are synthesized by oligomerization or polymerization of diene monomer via cycloaddition in the presence of a transition metal complex. Oligomers described herein, for example, comprise cyclobutane units in the oligomer backbone. Similarly, a polymers described herein comprise cyclobutane units in the polymer backbone.

A photocatalyst can be regenerated with increasing efficiency, turnover number and turnover frequency in the presence of air by irradiating the photocatalyst with a first range of wavelengths of light that excite the photocatalyst to an intermediate and irradiating the intermediate with a second range of wavelengths of light that turns the intermediate to the photocatalyst.