The present invention relates to an ultra-high molecular weight polyethylene (UHMWPE) powder having a BET specific surface area of ≥0.50 m.sup.2/g as determined in accordance with ISO 9277 (2010). Such UHMWPE powder allows for preparation of a gel solution comprising the powder to a desired swelling ratio at moderate temperatures within a reduced swelling period.

The present invention relates to an ultra-high molecular weight polyethylene (UHMWPE) powder having a BET specific surface area of ≥0.50 m.sup.2/g as determined in accordance with ISO 9277 (2010). Such UHMWPE powder allows for preparation of a gel solution comprising the powder to a desired swelling ratio at moderate temperatures within a reduced swelling period.

A process of preparing a solid catalyst component for the production of polypropylene includes a) dissolving a halide-containing magnesium compound in a mixture, the mixture including an epoxy compound, an organic phosphorus compound, and a hydrocarbon solvent to form a homogenous solution; b) treating the homogenous solution with an organosilicon compound during or after the dissolving step; c) treating the homogenous solution with a first titanium compound in the presence of a first non-phthalate electron donor, and an organosilicon compound, to form a solid precipitate; and d) treating the solid precipitate with a second titanium compound in the presence of a second non-phthalate electron donor to form the solid catalyst component, where the process is free of carboxylic acids and anhydrides.

A process of preparing a solid catalyst component for the production of polypropylene includes a) dissolving a halide-containing magnesium compound in a mixture, the mixture including an epoxy compound, an organic phosphorus compound, and a hydrocarbon solvent to form a homogenous solution; b) treating the homogenous solution with an organosilicon compound during or after the dissolving step; c) treating the homogenous solution with a first titanium compound in the presence of a first non-phthalate electron donor, and an organosilicon compound, to form a solid precipitate; and d) treating the solid precipitate with a second titanium compound in the presence of a second non-phthalate electron donor to form the solid catalyst component, where the process is free of carboxylic acids and anhydrides.

The present disclosure provides methods for producing an olefin polymer by contacting a C.sub.3-C.sub.40 olefin, ethylene and a diene with a catalyst system including an activator and a metallocene catalyst compound comprising a substituted or unsubstituted indacenyl group and obtaining a C.sub.3-C.sub.40 olefin-ethylene-diene terpolymer typically comprising from 1 to 35 mol % of ethylene, from 98.9 to 65 mol % C.sub.3-C.sub.40 olefin, and, optionally, from 0.1 to 10 mol % diene. Preferably, a propylene-ethylene-ethylidene norbornene is obtained.

The present disclosure provides methods for producing an olefin polymer by contacting a C.sub.3-C.sub.40 olefin, ethylene and a diene with a catalyst system including an activator and a metallocene catalyst compound comprising a substituted or unsubstituted indacenyl group and obtaining a C.sub.3-C.sub.40 olefin-ethylene-diene terpolymer typically comprising from 1 to 35 mol % of ethylene, from 98.9 to 65 mol % C.sub.3-C.sub.40 olefin, and, optionally, from 0.1 to 10 mol % diene. Preferably, a propylene-ethylene-ethylidene norbornene is obtained.

The present application relates to a process for producing ethylene polymer in a polymerization process comprising polymerisation of ethylene, optionally with comonomers selected from C.sub.3-C.sub.20-alpha-olefins, preferably selected from C.sub.4-C.sub.10-alpha-olefins, in the presence of a Ziegler-Natta catalyst under polymerisation conditions in at least one polymerisation stage carried out in a solution, slurry or gas-phase reactor or in combinations thereof, wherein the Ziegler-Natta catalyst comprises (A) a solid Ziegler-Natta catalyst component and (B) a cocatalyst, wherein the solid Ziegler-Natta catalyst component (A) comprises a solid support of a Mg compound, a transition metal of Group 4 to 6 and an internal electron donor.

The present application relates to a process for producing ethylene polymer in a polymerization process comprising polymerisation of ethylene, optionally with comonomers selected from C.sub.3-C.sub.20-alpha-olefins, preferably selected from C.sub.4-C.sub.10-alpha-olefins, in the presence of a Ziegler-Natta catalyst under polymerisation conditions in at least one polymerisation stage carried out in a solution, slurry or gas-phase reactor or in combinations thereof, wherein the Ziegler-Natta catalyst comprises (A) a solid Ziegler-Natta catalyst component and (B) a cocatalyst, wherein the solid Ziegler-Natta catalyst component (A) comprises a solid support of a Mg compound, a transition metal of Group 4 to 6 and an internal electron donor.

Supported chromium catalysts containing a solid oxide and 0.1 to 15 wt. % chromium, in which the solid oxide or the supported chromium catalyst has a particle size span from 0.5 to 1.4, less than 3 wt. % has a particle size greater than 100 μm, and less than 10 wt. % has a particle size less than 10 μm, can be contacted with an olefin monomer in a loop slurry reactor to produce an olefin polymer. Representative ethylene-based polymers produced using the chromium catalysts have a HLMI of 4 to 70 g/10 min, a density from 0.93 to 0.96 g/cm.sup.3, from 150 to 680 ppm solid oxide (such as silica), from 1.5 to 6.8 ppm chromium, and a film gel count of less than 15 catalyst particle gels per ft.sup.2 of 25 micron thick film and/or a gel count of less than or equal to 50 catalyst particles of greater than 100 μm per five grams of the ethylene polymer.

Supported chromium catalysts containing a solid oxide and 0.1 to 15 wt. % chromium, in which the solid oxide or the supported chromium catalyst has a particle size span from 0.5 to 1.4, less than 3 wt. % has a particle size greater than 100 μm, and less than 10 wt. % has a particle size less than 10 μm, can be contacted with an olefin monomer in a loop slurry reactor to produce an olefin polymer. Representative ethylene-based polymers produced using the chromium catalysts have a HLMI of 4 to 70 g/10 min, a density from 0.93 to 0.96 g/cm.sup.3, from 150 to 680 ppm solid oxide (such as silica), from 1.5 to 6.8 ppm chromium, and a film gel count of less than 15 catalyst particle gels per ft.sup.2 of 25 micron thick film and/or a gel count of less than or equal to 50 catalyst particles of greater than 100 μm per five grams of the ethylene polymer.