Dow Global Technolgoies LLC

Alexander W DeGroot

David T Gillespie

James C Stevens

Edmund M Carnahan

Daniel D VanderLende

Jeffrey D Weinhold

Sylvie Y Desjardins

Colin Li Pi Shan

Lonnie G Hazlitt

Peter B Arnoudse

Charles Allen Williams

Charles A Williams

A polymer composition that has a backbone chain; and a plurality of long chain branches connected to the backbone is described. The polymer composition also has a value ofg'-g&#x2032;g&#x2032;-g&#x2032;that is less than about 0.22, whereg&#x2032;g&#x2032;is the long chain branching index for a fraction of the composition having a Mof 100,000 andg&#x2032;g&#x2032;is the long chain branching index for a fraction of the composition having a Mof 500,000.

High melt strength polymers and method of making same

A process of making a polymer is described. The process includes contacting one or more olefinic monomers in the presence of at least a high molecular weight (HMW) catalyst and at least a low molecular weight (LMW) catalyst in a polymerization reactor system; and effectuating the polymerization of the one or more olefinic monomers in the polymerization reactor system to obtain an olefin polymer, wherein the LMW catalyst has an R, defined as wherein [vinyl] is the concentration of vinyl groups in the olefin polymer produced by the low molecular weight catalyst expressed in vinyls/1,000 carbon atoms; [vinylidene], [cis] and [trans] are the concentration of vinylidene, cis and trans groups in the olefin polymer expressed in the number of the respective groups per 1,000 carbon atoms, of greater than 0.12, and wherein the HMW catalyst has a reactivity ratio, r1 of about 5 or less.

Apparatus for GPC/TREF and TREF/GPC characterization of a polymer sample. The apparatus provides for the automated and integrated use of multiple TREF columns and a GPC system employing a multiple flow through detectors. In addition, a method for TREF/GPC characterization of a polymer sample by GPC analysis of TREF fractions at increasing TREF elution temperatures from multiple TREF columns operated in a coordinated and synchronized temperature cycle for increased sample throughput. Also, a method for GPC/TREF characterization of a polymer sample by GPC fractionation followed by TREF fractionation of the GPC fractionations.

Apparatus and method for polymer characterization

A polymer composition comprises: (a) a high molecular weight, branched component; and (b) a low molecular weight, branched component. Some polymer compositions are characterized by a substantial absent of amyl or methyl branches and a melt strength (MS) that satisfies the following relationship:where x is greater than or equal to about 12.5 and y is greater than or equal to about 3. Some polymers are characterized by a melt strength (MS) that satisfies the following relationship:where x is greater than or equal to about 3 and y is greater than or equal to about 4.5 and a molecular weight distribution of greater than 3. A process for making polymers is also disclosed.

A polymer composition that has a backbone chain; and a plurality of long chain branches connected to the backbone is described. The polymer composition also has a value ofg'-g&#x2032;that is less than about 0.22, whereg&#x2032;is the long chain branching index for a fraction of the composition having a Mof 100,000 andg&#x2032;is the long chain branching index for a fraction of the composition having a Mof 500,000.

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Lake Jackson, TX, United States of America

Alexander W DeGroot