Patent classifications
C08F2/002
METHODS FOR FORMING ULTRA HIGH MOLECULAR WEIGHT POLYETHYLENES AND METHODS FOR REDUCING CONTAMINANT CONTENT IN SUCH
According to one or more embodiments disclosed herein, the amount of one or more contaminants in an initial ultra high molecular weight polyethylene composition may be reduced by a method including contacting the initial ultra high molecular weight polyethylene composition with an acid to form a processed ultra high molecular weight polyethylene composition. The initial ultra high molecular weight polyethylene composition may include at least 0.02 wt. % of one or more contaminants. The contacting of the acid with the initial ultra high molecular weight polyethylene composition may be for a time, at a pressure, and at a temperature sufficient to reduce the amount of the one or more contaminants in the initial ultra high molecular weight polyethylene.
ALKANE-SOLUBLE NON-METALLOCENE PRECATALYSTS
A compound of formula (1) as drawn herein, wherein M is a Group 4 metal and each R independently is a silicon-free organic solubilizing group. A method of synthesizing the compound (1). A solution of compound (1) in alkane solvent. A catalyst system comprising or made from compound (1) and an activator. A method of polymerizing an olefin monomer with the catalyst system.
ALKANE-SOLUBLE NON-METALLOCENE PRECATALYSTS
A compound of formula (1) as drawn herein, wherein M is a Group 4 metal and each R independently is a silicon-free organic solubilizing group. A method of synthesizing the compound (1). A solution of compound (1) in alkane solvent. A catalyst system comprising or made from compound (1) and an activator. A method of polymerizing an olefin monomer with the catalyst system.
LOOP SLURRY PERIODOGRAM CONTROL TO PREVENT REACTOR FOULING AND REACTOR SHUTDOWNS
Methods for operating a polymerization reactor system are described, and these methods include the steps of contacting a transition metal-based catalyst system with an olefin monomer and an optional olefin comonomer in the polymerization reactor system comprising a loop slurry reactor and a reactor circulating pump under polymerization conditions to produce an olefin polymer; measuring a kW power consumption of the reactor circulating pump to generate power consumption versus time data; converting the power consumption versus time data using frequency analysis to generate intensity versus frequency data at a first frequency interval encompassing a time equal to one-half an average recirculation period in the loop slurry reactor, and intensity versus frequency data at a second frequency interval encompassing a time equal to the average full recirculation period in the loop slurry reactor; and reducing a production rate of the olefin polymer in the loop slurry reactor when a total of a first peak intensity at the first frequency interval and a second peak intensity at the second frequency interval is equal to 10,000 or more, or when the rate of change of the first peak intensity or the rate of change of the second peak intensity is equal to 5,000/hr or more.
Methods for forming ultra high molecular weight polyethylenes and methods for reducing contaminant content in such
According to one or more embodiments disclosed herein, the amount of one or more contaminants in an initial ultra high molecular weight polyethylene composition may be reduced by a method including contacting the initial ultra high molecular weight polyethylene composition with an acid to form a processed ultra high molecular weight polyethylene composition. The initial ultra high molecular weight polyethylene composition may include at least 0.02 wt. % of one or more contaminants. The contacting of the acid with the initial ultra high molecular weight polyethylene composition may be for a time, at a pressure, and at a temperature sufficient to reduce the amount of the one or more contaminants in the initial ultra high molecular weight polyethylene.
Methods for forming ultra high molecular weight polyethylenes and methods for reducing contaminant content in such
According to one or more embodiments disclosed herein, the amount of one or more contaminants in an initial ultra high molecular weight polyethylene composition may be reduced by a method including contacting the initial ultra high molecular weight polyethylene composition with an acid to form a processed ultra high molecular weight polyethylene composition. The initial ultra high molecular weight polyethylene composition may include at least 0.02 wt. % of one or more contaminants. The contacting of the acid with the initial ultra high molecular weight polyethylene composition may be for a time, at a pressure, and at a temperature sufficient to reduce the amount of the one or more contaminants in the initial ultra high molecular weight polyethylene.
Poly alpha-olefins, compositions thereof, and methods of making
The present disclosure relates to methods of making poly alpha-olefins and compositions thereof. In some embodiments, a method for making a poly alpha-olefin includes agitating in a first reaction vessel for about 30 seconds or greater a composition comprising a transition metal halide, an electron donor, a co-catalyst, and a C.sub.4-C.sub.20 alpha-olefin. The method includes transferring the composition from the first reaction vessel to a second reaction vessel. The present disclosure further relates to poly alpha-olefins and compositions thereof for reducing drag in the flow of hydrocarbons such as crude oil or refined products in pipes. In at least one embodiment, a composition includes a coated poly alpha-olefin and an inert carrier.
Method of preparing aromatic vinyl compound-vinyl cyanide compound polymer and apparatus for preparing the same
A method of preparing an aromatic vinyl compound-vinyl cyanide compound polymer includes polymerizing a reaction mixture containing an aromatic vinyl compound, a vinyl cyanide compound, and an organic solvent in a reactor and transferring the vaporized reaction mixture present in the upper space of the reactor to a heat exchanger via a pipe and condensing the vaporized reaction mixture. The condensed reaction mixture is transferred to one side of the pipe and sprayed into the pipe, the flow velocity of the reaction mixture vaporized in the reactor is reduced, and temperature is lowered. Accordingly, a phenomenon wherein polymer particles in a reactor are sucked into a heat exchanger is prevented, and occurrence of polymerization in the heat exchanger is suppressed. Therefore, productivity and quality may be improved.
Method of preparing aromatic vinyl compound-vinyl cyanide compound polymer and apparatus for preparing the same
A method of preparing an aromatic vinyl compound-vinyl cyanide compound polymer includes polymerizing a reaction mixture containing an aromatic vinyl compound, a vinyl cyanide compound, and an organic solvent in a reactor and transferring the vaporized reaction mixture present in the upper space of the reactor to a heat exchanger via a pipe and condensing the vaporized reaction mixture. The condensed reaction mixture is transferred to one side of the pipe and sprayed into the pipe, the flow velocity of the reaction mixture vaporized in the reactor is reduced, and temperature is lowered. Accordingly, a phenomenon wherein polymer particles in a reactor are sucked into a heat exchanger is prevented, and occurrence of polymerization in the heat exchanger is suppressed. Therefore, productivity and quality may be improved.
CORE-SHELL FLOW IMPROVER
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.