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.

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.

A solution of a mixed alkaline earth alkoxide compound with an aluminum compound in an aprotic solvent, and methods of making and using them.

A solution of a mixed alkaline earth alkoxide compound with an aluminum compound in an aprotic solvent, and methods of making and using them.

This disclosure relates to rotomolded articles, having a wall structure, where the wall structure contains at least one layer containing an ethylene interpolymer product, or a blend containing an ethylene interpolymer product and an ethylene polymer, where the ethylene interpolymer product has a Dilution Index (Y.sub.d) greater than 0 and improved Environmental Stress Crack Resistance (ESCR). The ethylene interpolymer product has a melt index from about 0.5 to about 15 dg/minute, a density from about 0.930 to about 0.955 g/cm.sup.3, a polydispersity (M.sub.w/M.sub.n) from about 2 to about 6 and a CDBI.sub.50 from about 50% to about 98%. Further, the ethylene interpolymer products are a blend of at least two ethylene interpolymers; where one ethylene interpolymer is produced with a single-site catalyst formulation and at least one ethylene interpolymer is produced with a heterogeneous catalyst formulation.

This disclosure relates to rotomolded articles, having a wall structure, where the wall structure contains at least one layer containing an ethylene interpolymer product, or a blend containing an ethylene interpolymer product and an ethylene polymer, where the ethylene interpolymer product has a Dilution Index (Y.sub.d) greater than 0 and improved Environmental Stress Crack Resistance (ESCR). The ethylene interpolymer product has a melt index from about 0.5 to about 15 dg/minute, a density from about 0.930 to about 0.955 g/cm.sup.3, a polydispersity (M.sub.w/M.sub.n) from about 2 to about 6 and a CDBI.sub.50 from about 50% to about 98%. Further, the ethylene interpolymer products are a blend of at least two ethylene interpolymers; where one ethylene interpolymer is produced with a single-site catalyst formulation and at least one ethylene interpolymer is produced with a heterogeneous catalyst formulation.

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.

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.

The heterogeneous procatalyst of this disclosure includes a titanium species; a hydrocarbon soluble transition metal compound having a structure M(OR.sup.1).sub.z; a chlorinating agent having a structure A(Cl).sub.x(R.sup.2).sub.3-x, and a magnesium chloride component. M of M(OR.sup.1).sub.z is a non-reducing transition metal other than titanium, the non-reducing transition metal being in an oxidation state of +2 or +3. Each R.sup.1 is independently (C.sub.1-C.sub.30)hydrocarbyl or —C(O)R.sup.11, where R.sup.11 is (C.sub.1-C.sub.30)hydrocarbyl. Subscript z of M(OR.sup.1).sub.z is 2 or 3. Each R.sup.1 and R.sup.11 may be optionally substituted with one or more than one halogen atoms, or one or more than one —Si(R.sup.S).sub.3, where each R.sup.S is (C.sub.1-C.sub.30)hydrocarbyl. A of A(Cl).sub.x(R.sup.2).sub.3-x is aluminum or boron; R.sup.2 is (C.sub.1-C.sub.30)hydrocarbyl; and x is 1, 2, or 3; and a magnesium chloride component.

The heterogeneous procatalyst of this disclosure includes a titanium species; a hydrocarbon soluble transition metal compound having a structure M(OR.sup.1).sub.z; a chlorinating agent having a structure A(Cl).sub.x(R.sup.2).sub.3-x, and a magnesium chloride component. M of M(OR.sup.1).sub.z is a non-reducing transition metal other than titanium, the non-reducing transition metal being in an oxidation state of +2 or +3. Each R.sup.1 is independently (C.sub.1-C.sub.30)hydrocarbyl or —C(O)R.sup.11, where R.sup.11 is (C.sub.1-C.sub.30)hydrocarbyl. Subscript z of M(OR.sup.1).sub.z is 2 or 3. Each R.sup.1 and R.sup.11 may be optionally substituted with one or more than one halogen atoms, or one or more than one —Si(R.sup.S).sub.3, where each R.sup.S is (C.sub.1-C.sub.30)hydrocarbyl. A of A(Cl).sub.x(R.sup.2).sub.3-x is aluminum or boron; R.sup.2 is (C.sub.1-C.sub.30)hydrocarbyl; and x is 1, 2, or 3; and a magnesium chloride component.