A composition comprising an ethylene-based polymer, which comprises the following properties: a) (Mw(abs)/Mw(conv)2.00)*(100,000 g/mol/Mw(abs))*CDF?IR #191 (MW10,000 g/mol)0.030; and b) a melt index (I2) from 0.30 to 2.50 g/10 min.

The present invention relates to a continuous high-pressure polymerization process for the preparation of a liquid ethylene copolymer which comprises in polymerized form ethylene; and more than 10 wt % of a reactive acrylate which is selected from glycidyl acrylate and glycidyl methacrylate, where a monomer feed comprising the ethylene and the reactive acrylate is polymerized in the presence of at least 2 wt % of a chain transfer agent.

A process or apparatus for producing polyethylene with improved film thinning and handleability involves polymerizing high-pressure ethylene using an autoclave-type reactor in the presence of a polymerization initiator. The reaction zone of the reactor has at least two different temperature sections; the polymerization initiator and the ethylene are supplied to the upstream temperature section in the reaction zone and the ethylene is polymerized to generate polyethylene; unreacted ethylene and the polyethylene generated at the upstream temperature section in the reactor flow into the downstream temperature section in communication with the upstream temperature section, so that additional polyethylene is generated at the downstream temperature section. A difference (T [ C.]) between a temperature (T1 [ C.]) of the temperature section positioned upstream and a temperature (T2 [ C.]) of the temperature section positioned downstream in the reaction zone that receives the polymerization initiator and is in the autoclave-type reactor is 2.1 C. to 8.4 C.

Disclosed are high-pressure polymerization methods and systems using optimized operation sequence logic established at least partly from an analysis of a database containing data of previous operations. The optimized operation sequence logic and collected current process and system data are used to automate the operation of a high pressure ethylene polymerization process and unit.

One embodiment of the present specification provides a method for preparing a latex composition for dip-forming, the method including: (a) preparing a monomer mixture including a conjugated diene-based monomer, a farnesene monomer, an ethylenically unsaturated nitrile monomer, and an ethylenically unsaturated acid monomer; (b) adding an additive including an emulsifier and an inorganic solvent to the monomer mixture; and (c) polymerizing the monomer mixture to prepare a copolymer latex, wherein a weight ratio of the farnesene monomer to a total weight of the conjugated diene-based monomer and the farnesene monomer is 5 to 55%.

A branched propylene-based polymer having the following properties (1) to (5): property (1): MFR of 10 g/10 min to 100 g/10 min; property (2): Mw/Mn is 2.5 or more and less than 3.5; Mz/Mw is 3.0 to 4.7; and Mz is 50.0?10.sup.4 to 94.0?10.sup.4; property (3): in an integral molecular weight distribution curve obtained by GPC, a percentage of a component having a molecular weight of 100?10.sup.4 or more, is 1.5 mass to 4.0 mass %; property (4): in a molecular weight distribution curve obtained by 3D-GPC, a branching index g(100?10.sup.4) at an absolute molecular weight M.sub.abs of 100?10.sup.4 is more than 0.70 and 0.85 or less; and property (5): a ratio [?*(0.01)?*(100)] between a complex viscosity ?*(0.01) and a complex viscosity ?*(100) in dynamic viscoelasticity measurement, is 4.0 to 20, and ?*(0.01)/?*(100) and the MFR satisfy specific relations.

This disclosure relates to systems and processes for cooling polymer product mixtures manufactured at high pressure. The processes of the invention involve cooling and then subsequently reducing the pressure of the product mixture from the reactor. In the systems of the invention, a product cooler is located downstream of the high pressure reactor and upstream of a high pressure let down valve.

Controlling the shutdown of a polyethylene reactor system that includes a secondary compressor, a reactor, a high pressure let down valve (HPLDV), a high-pressure separator, and a high-pressure recycle gas system is provided. After a partial or complete shutdown of secondary compressor, HPLDV opens to a pre-set open position until the reactor pressure reduces to either a pre-set reduced pressure limit or a until the slope of the reactor gas density to reactor pressure exceeds 0.15. The HPLDV controls the pressure to a pressure set point.

The present application provides a catalyst for copolymerization of ethylene and methyl methacrylate and an application thereof. The catalyst includes a main catalyst, and the main catalyst is obtained by compounding a compound of formula (I) and a compound of formula (II); a mole ratio of the compound of formula (I) to the compound of formula (II) is (1:49) to (49:1). The catalyst has an excellent catalytic activity, and a copolymer of ethylene and methyl methacrylate with a high molecular weight can be obtained, with a weight average molecular weight of not less than 1?10.sup.5 g/mol.

A process for polymerizing ethylene in a high-pressure polymerization system having a continuously operated polymerization reactor and a reactor blow down system having an emergency valve, a reactor blow down vessel containing an aqueous medium and a reactor blow down dump vessel, wherein the process includes the steps of monitoring the polymerization system for a disturbance, opening the emergency valve when a disturbance occurs to allow the content of the polymerization system to expand into the reactor blow down vessel, contacting the content of the polymerization system in the reactor blow down vessel with the aqueous medium to obtain an aqueous polymer slurry, separating the polymer slurry and gaseous components, and transferring the polymer slurry to the reactor blow down dump vessel.