C08F4/655

Multimodal ethylene-based polymer processing systems and methods

Embodiments of methods for producing a trimodal polymer in a solution polymerization process comprise three solution polymerization reactors organized in parallel or in series.

Cable jacket composition

The present invention relates to a cable jacket composition comprising a multimodal olefin copolymer, wherein said olefin copolymer has a density of 0.935-0.960 g/cm3 and MFR2 of 1.5-10.0 g/10 min and comprises a bimodal polymer mixture of a low molecular weight homo- or copolymer and a high molecular weight copolymer wherein the composition has ESCR of at least 2000 hours and wherein the numerical values of cable wear index and composition MFR2 (g/10 min) follow the correlation: Wear index<15.500+0.900*composition MFR2. The invention further relates to the process for preparing said composition and its use as outer jacket layer for a cable, preferably a communication cable, most preferably a fiber optic cable.

Activator-nucleator formulations

An activator-nucleator formulation comprising an activating effective amount of (A) an alkylaluminum(chloride) compound (compound (A)); and a nucleating effective amount of a compound (B) selected from at least one of compounds (B1) to (B3): (B1) calcium (1R,2S)-cis-cyclohexane-1,2-dicarboxylate (1:1); (B2) calcium stearate (1:2), and (B3) zinc stearate (1:2); wherein the compound (A) is effective for activating a Ziegler-Natta procatalyst to give a Ziegler-Natta catalyst; and wherein the compound (B) is effective for lowering isothermal crystallization peak time period of a semicrystalline polyethylene polymer made in a polymerization process by the Ziegler-Natta catalyst. A method of polymerizing ethylene, and optionally 0, 1, or more alpha-olefin comonomers, in a polymerization process conducted in a polymerization reactor, the method comprising contacting ethylene, and optionally 0, 1, or more alpha-olefin comonomers, with the Ziegler-Natta catalyst system to give a semicrystalline polyethylene polymer. The semicrystalline polyethylene polymer made by the method of polymerizing.

Process for the preparation of an UHMWPE homopolymer

A process for the preparation of an ultra-high molecular weight ethylene homopolymer having a MFR.sub.21 of 0.01 g/10 min or less, said process comprising: (I) prepolymerising at least ethylene at a temperature of 0 to 90° C. in the presence of a heterogeneous Ziegler Natta catalyst to prepare an ethylene prepolymer having an Mw of 40,000 to 600,000 g/mol; and thereafter in the presence of the prepolymer and said catalyst; (II) polymerising ethylene at a temperature of 55° C. or less, such as 20 to 55° C., to prepare said UHMW ethylene homopolymer; wherein the UHMW ethylene homopolymer comprises up to 8 wt. % of said prepolymer.

POLYMERISATION METHOD AND APPARATUS THEREFOR

A method of assembling and/or operating apparatus for undertaking a chemical reaction. The apparatus includes a housing in which a precursor of a receptacle is arranged. A fluid (F1) may be introduced into said precursor to cause the precursor to inflate.

POLYMERISATION METHOD AND APPARATUS THEREFOR

A method of assembling and/or operating apparatus for undertaking a chemical reaction. The apparatus includes a housing in which a precursor of a receptacle is arranged. A fluid (F1) may be introduced into said precursor to cause the precursor to inflate.

SOLID CATALYST FOR THE (CO)POLYMERISATION OF ALPHA-OLEFINS AND PROCESS FOR THE PREPARATION THEREOF
20170216825 · 2017-08-03 · ·

An improved solid Ziegler-Natta type catalyst for the (co)polymerisation of ethylene and α-olefins, particularly in high-temperature processes, such as for example adiabatic solution processes and high-pressure adiabatic processes with elevated productivity, is provided. Said catalyst is obtained by means of an original process comprising dissolving in hydrocarbons, compounds of titanium, magnesium and optionally a metal selected from hafnium and zirconium, and reprecipitating them in two steps in succession, the first of which is chlorination and the second reduction.

SOLID CATALYST FOR THE (CO)POLYMERISATION OF ALPHA-OLEFINS AND PROCESS FOR THE PREPARATION THEREOF
20170216825 · 2017-08-03 · ·

An improved solid Ziegler-Natta type catalyst for the (co)polymerisation of ethylene and α-olefins, particularly in high-temperature processes, such as for example adiabatic solution processes and high-pressure adiabatic processes with elevated productivity, is provided. Said catalyst is obtained by means of an original process comprising dissolving in hydrocarbons, compounds of titanium, magnesium and optionally a metal selected from hafnium and zirconium, and reprecipitating them in two steps in succession, the first of which is chlorination and the second reduction.

Spray-dried Ziegler-Natta (pro)catalyst systems

Methods of making spray-dried Ziegler-Natta (pro)catalyst systems containing titanium Ziegler-Natta (pro)catalysts, a hydrophobic silica carrier material, and tetrahydrofuran. The spray-dried Ziegler-Natta (pro)catalyst systems made by the method. Methods of polymerizing olefin (co)monomer(s) with the spray-dried Ziegler-Natta catalyst system to make polyolefin polymers, and the polyolefin polymers made thereby.

PROCESS FOR PREPARATION OF MULTIMODAL POLYOLEFIN

The invention relates to a process for the preparation of a multimodal copolymer of ethylene and a comonomer which is 1-hexene and/or 1-butene in a series of polymerization reactors comprising at least a first polymerization reactor and a second polymerization reactor, the process comprising: a) feeding ethylene, hydrogen and catalyst components (1) and a first diluent (29) to the first polymerization reactor (A) to prepare a first suspension (3) of solid particles of a first ethylene polymer in a first suspension medium, wherein the first diluent (29) comprises branched heptane and is essentially free of the comonomer; b) feeding the first suspension (3) to a flash drum (E) for vaporizing a part of the first suspension medium to obtain a hydrogen-depleted suspension (4), c) feeding the hydrogen-depleted suspension (4), ethylene and comonomer (9) and a second diluent (24 & 34) to the second polymerization reactor (H) to prepare a second suspension (11) of solid particles of a second ethylene polymer in a second suspension medium, wherein the second diluent (24 & 34) comprises branched heptane and the comonomer dissolved in the second diluent, d) processing the second suspension (11) to obtain a dry effluent (15) of the solid particles of the second ethylene polymer and a liquid stream (23) comprising branched heptane, the comonomer, and low molecular weight hydrocarbon reaction products, e) feeding at least part (25) of the liquid stream (23) to an evaporation system (Q) for separating non-volatile, low-molecular-weight hydrocarbon reaction products and subsequently to a distillation column (R) for separating the comonomer from branched heptane to obtain 1) a branched heptane liquid stream (29) essentially free of the comonomer, 2) a vapor distillate (31) comprising the comonomer and branched heptane and 3) a liquid distillate (30) comprising branched heptane and the comonomer, f) feeding the liquid distillate stream (30) to the second polymerization reactor (B) to form at least part of the second diluent (34) and g) feeding the branched heptane liquid stream (29) to the first polymerization reactor as the first diluent.