A hydrogel comprising water, and a plurality of titanium-silica nanoparticle agglomerates, wherein each titanium-silica nanoparticle agglomerate is an agglomeration of titanium-silica nanoparticles, the agglomerates having an average titanium loading designated x with a coefficient of variation for the average titanium loading of less than about 1.0, wherein a silica content of the hydrogel is of from about 10 wt. % to about 35 wt. % based on a total weight of the hydrogel.

A hydrogel comprising water, and a plurality of titanium-silica nanoparticle agglomerates, wherein each titanium-silica nanoparticle agglomerate is an agglomeration of titanium-silica nanoparticles, the agglomerates having an average titanium loading designated x with a coefficient of variation for the average titanium loading of less than about 1.0, wherein a silica content of the hydrogel is of from about 10 wt. % to about 35 wt. % based on a total weight of the hydrogel.

Supported chromium catalysts with an average valence less than +6 and having a hydrocarbon-containing or halogenated hydrocarbon-containing ligand attached to at least one bonding site on the chromium are disclosed, as well as ethylene-based polymers with terminal alkane, aromatic, or halogenated hydrocarbon chain ends. Another ethylene polymer characterized by at least 2 wt. % of the polymer having a molecular weight greater than 1,000,000 g/mol and at least 1.5 wt. % of the polymer having a molecular weight less than 1000 g/mol is provided, as well as an ethylene homopolymer with at least 3.5 methyl short chain branches and less than 0.6 butyl short chain branches per 1000 total carbon atoms.

Macrocyclic polyalkene homopolymers and copolymers can be formed and converted to macrocyclic polyalkanes or macrocyclic poly(alkane-co-alkene) upon hydrogenation or, when the macrocyclic polyalkene is reacted with an alkene in the presence of an olefin metathesis catalyst, to a macrocyclic poly(alkane-co-alkene) comprising vicinal C(CR2)'s. Upon hydrogenation of a macrocyclic poly(alkane-co-alkene) comprising vicinal C(CR2)-'s, macrocyclic poly(alkane)s or poly(alkane-co-alkene)s with isolated C(CR2)- groups can be provided, depending on the degree of hydrogenation. The poly(alkane-co-alkene)s with isolated C(CR2)- units can be used to form poly(macrocyclic poly(alkane-co-alkene))s, poly(macrocyclic poly(alkane))s, and/or bi-, tri-, and/or multi-macrocyclic poly(alkane-co-alkene)s or bi-, tri-, and/or multi-macrocyclic poly(alkane)s.

Disclosed are saturated cyclic monopolymers derived from hexyne, octyne, nonyne, pentadecyne and saturated cyclic copolymers derived from acetylene and a second alkyne monomer that is hexyne, octyne, nonyne, or pentadecyne.

Disclosed are saturated cyclic monopolymers derived from hexyne, octyne, nonyne, pentadecyne and saturated cyclic copolymers derived from acetylene and a second alkyne monomer that is hexyne, octyne, nonyne, or pentadecyne.

This disclosure provides for polymerization processes of polyolefins wherein the melt index can be regulated. For example, there is provided a process for producing a polyethylene, the process comprising: (1) in a polymerization reactor, contacting (a) a polymerization catalyst, (b) ethylene, (c) an optional -olefin comonomer, and (d) (x+y) ppm by weight of an antistatic agent on an ethylene basis; and (2) applying reaction conditions to the reaction mixture suitable to produce the polyethylene having a desired set of characteristics, such as desired target melt index. The disclosed polymerization processes allow for production of polyolefins having higher melt indices, and in the alternative to produce polyolefins having a desired target melt index at lower polymerization temperatures.

Methods for reinforcing chromium catalysts by the deposition of additional silica are disclosed herein. The resultant silica-reinforced chromium supported catalysts can be used to polymerize olefins to produce, for example, ethylene based homopolymers and copolymers with higher molecular weights and additional long chain branching.

Methods for reinforcing chromium catalysts by the deposition of additional silica are disclosed herein. The resultant silica-reinforced chromium supported catalysts can be used to polymerize olefins to produce, for example, ethylene based homopolymers and copolymers with higher molecular weights and additional long chain branching.

The present disclosure generally relates to ethylene alpha-olefin copolymers and methods of making ethylene alpha-olefin copolymers. The ethylene alpha-olefin copolymers may have a density of about 0.915 g/mL to about 0.918 g/mL, a rheological polydispersity index greater than 0.8, a melt index of about 0.4 dg/10 min to about 2.0 dg/10 min, and/or a CEF T.sub.50 of 84 C. or less. The ethylene alpha-olefin copolymers may be made by combining an ethylene monomer and one or more alpha-olefin monomers in the presence of a catalyst, such as a Ziegler-Natta catalyst.