Abstract: A composition comprising a polyethylene wherein the composition is enriched in polymer molecules having topological variations by an enrichment factor ? and wherein the composition displays a long chain branching frequency of greater than about 0.5 long chain branches per 1000 total carbon atoms. A composition comprising an isolated Ziegler-catalyzed polyethylene having a long chain branching frequency of greater than about 0.5 long chain branches per 1000 total carbon atoms at the high molecular weight end.

Abstract: A composition comprising a polyethylene wherein the composition is enriched in polymer molecules having topological variations by an enrichment factor ? and wherein the composition displays a long chain branching frequency of greater than about 0.5 long chain branches per 1000 total carbon atoms. A composition comprising an isolated Ziegler-catalyzed polyethylene having a long chain branching frequency of greater than about 0.5 long chain branches per 1000 total carbon atoms at the high molecular weight end.

Abstract: Polymer fractions such as polyethylene fractions can be produced that have a PDI less than about 2.3 and a Mw greater than about 1,000,000 g/mol, 3,000,000 g/mol, or 6,000,000 g/mol. Such polyethylene fractions are separated from a UHMWPE parent polymer by first dissolving the parent polymer in a relatively good solvent. The conditions employed for such dissolution are selected to reduce the degradation of the parent polymer. The resulting parent solution is transported into a fractionation column in which a support is disposed. The fractionation column is thereafter operated at conditions effective to form a precipitate on the support comprising the desired polyethylene fraction. The polyethylene fraction may then be recovered from the fractionation column by repeatedly displacing a solvent/non-solvent mixture into the column to dissolve the polyethylene fraction. The relative concentrations of the solvent and the non-solvent are based on a solvent gradient profile of the polyethylene parent polymer.

Abstract: Polymer fractions such as polyethylene fractions can be produced that have a PDI less than about 2.3 and a Mw greater than about 1,000,000 g/mol, 3,000,000 g/mol, or 6,000,000 g/mol. Such polyethylene fractions are separated from a UHMWPE parent polymer by first dissolving the parent polymer in a relatively good solvent. The conditions employed for such dissolution are selected to reduce the degradation of the parent polymer. The resulting parent solution is transported into a fractionation column in which a support is disposed. The fractionation column is thereafter operated at conditions effective to form a precipitate on the support comprising the desired polyethylene fraction. The polyethylene fraction may then be recovered from the fractionation column by repeatedly displacing a solvent/non-solvent mixture into the column to dissolve the polyethylene fraction. The relative concentrations of the solvent and the non-solvent are based on a solvent gradient profile of the polyethylene parent polymer.

Abstract: Polymer fractions such as polyethylene fractions can be produced that have a PDI less than about 2.3 and a Mw greater than about 1,000,000 g/mol, 3,000,000 g/mol, or 6,000,000 g/mol. Such polyethylene fractions are separated from a UHMWPE parent polymer by first dissolving the parent polymer in a relatively good solvent. The conditions employed for such dissolution are selected to reduce the degradation of the parent polymer. The resulting parent solution is transported into a fractionation column in which a support is disposed. The fractionation column is thereafter operated at conditions effective to form a precipitate on the support comprising the desired polyethylene fraction. The polyethylene fraction may then be recovered from the fractionation column by repeatedly displacing a solvent/non-solvent mixture into the column to dissolve the polyethylene fraction. The relative concentrations of the solvent and the non-solvent are based on a solvent gradient profile of the polyethylene parent polymer.

Abstract: Polymer fractions such as polyethylene fractions can be produced that have a PDI less than about 2.3 and a Mw greater than about 1,000,000 g/mol, 3,000,000 g/mol, or 6,000,000 g/mol. Such polyethylene fractions are separated from a UHMWPE parent polymer by first dissolving the parent polymer in a relatively good solvent. The conditions employed for such dissolution are selected to reduce the degradation of the parent polymer. The resulting parent solution is transported into a fractionation column in which a support is disposed. The fractionation column is thereafter operated at conditions effective to form a precipitate on the support comprising the desired polyethylene fraction. The polyethylene fraction may then be recovered from the fractionation column by repeatedly displacing a solvent/non-solvent mixture into the column to dissolve the polyethylene fraction. The relative concentrations of the solvent and the non-solvent are based on a solvent gradient profile of the polyethylene parent polymer.