A process to prepare an ethylene-based polymer, said process comprising polymerizing a mixture comprising ethylene, at a pressure greater than, or equal to, 100 MPa, in the presence of at least one free-radical initiator; and in a reactor system comprising at least one reactor and at least one Hyper-compressor, and wherein at least one oil formulation, optionally comprising one or more lubrication agents, is added to the Hyper-compressor; and wherein at least one of the following steps takes place: A) thermally treating the one or more lubrication agents, in an oxygen-free atmosphere, to achieve a peroxide level ≤10 ppm, based on the weight of the lubrication agent(s), and then adding said agent(s) to the oil formulation, prior to adding the oil formulation to the Hyper-compressor; or B) thermally treating the oil formulation, in an oxygen-free atmosphere, to achieve a peroxide level ≤10 ppm, based on the weight of the oil formulation, prior to adding the oil formulation to the Hyper-compressor; C) a combination of A and B.

A process to prepare an ethylene-based polymer, said process comprising polymerizing a mixture comprising ethylene, at a pressure greater than, or equal to, 100 MPa, in the presence of at least one free-radical initiator; and in a reactor system comprising at least one reactor and at least one Hyper-compressor, and wherein at least one oil formulation, optionally comprising one or more lubrication agents, is added to the Hyper-compressor; and wherein at least one of the following steps takes place: A) thermally treating the one or more lubrication agents, in an oxygen-free atmosphere, to achieve a peroxide level ≤10 ppm, based on the weight of the lubrication agent(s), and then adding said agent(s) to the oil formulation, prior to adding the oil formulation to the Hyper-compressor; or B) thermally treating the oil formulation, in an oxygen-free atmosphere, to achieve a peroxide level ≤10 ppm, based on the weight of the oil formulation, prior to adding the oil formulation to the Hyper-compressor; C) a combination of A and B.

According to the present disclosure, a catalyst composition capable of preparing a polyolefin having excellent mechanical stability, while exhibiting excellent process stability and high polymerization activity during the preparation of a polyolefin in a slurry process, and a method for preparing a polyolefin using the same is provided.

According to the present disclosure, a catalyst composition capable of preparing a polyolefin having excellent mechanical stability, while exhibiting excellent process stability and high polymerization activity during the preparation of a polyolefin in a slurry process, and a method for preparing a polyolefin using the same is provided.

A flow improver comprising a plurality of core-shell particles that can be formed by emulsion polymerization. The core of the core-shell particles can include a drag reducing polymer, while the shell of the particles can include repeat units of a hydrophobic compound and an amphiphilic compound. The flow improver can demonstrate increased pumping stability over conventionally prepared latex flow improvers.

A method for controlling the start up conditions in a gas phase polymerization process is provided. An inventory can be calculated for each monomer, comonomer, and hydrogen sufficient to produce a polyethylene polymer having desired properties, such as, a certain melt index and/or density.

A method for controlling the start up conditions in a gas phase polymerization process is provided. An inventory can be calculated for each monomer, comonomer, and hydrogen sufficient to produce a polyethylene polymer having desired properties, such as, a certain melt index and/or density.

Provided is a method of predicting fouling during a process of preparing polyolefin. According to the present invention, occurrence of fouling may be predicted in real-time with high reliability during a copolymerization process of preparing polyolefin. Therefore, productivity of the polyolefin preparation process may be further increased.

Provided is a method of predicting fouling during a process of preparing polyolefin. According to the present invention, occurrence of fouling may be predicted in real-time with high reliability during a copolymerization process of preparing polyolefin. Therefore, productivity of the polyolefin preparation process may be further increased.

A process for preparing vinyl acetate-ethylene copolymers in the form of an aqueous dispersion. The process includes providing an aqueous dispersion of vinyl acetate-ethylene copolymers and subjecting the aqueous dispersion of vinyl acetate-ethylene copolymers to radically initiated emulsion polymerization in a continuously operated tubular-reactor. Where one or more dividing plates bearing liquid-permeable openings that are mounted within the tubular-reactor transverse to the flow direction of the reactor contents.