Member since: 2019
Organization: IMP INSA lyon
Good results in combination with Acquity APC from Waters
Application Area: Polymers from polycondensation polyesters and polyamides
"microViscoStar is easy to use, with good results and reproductibility. It was purchased to be used with Acquity APC from Waters and results obtained are good."
When coupled with UHPLC size-exclusion chromatography and a compatible concentration detector such as the Optilab UT-rEX, the microViscoStar derives the intrinsic viscosity (IV) of polymers, rapidly and with minimal sample and solvent consumption. An inherently valuable physico-chemical property in itself, IV is best utilized together with molar mass information from a µDAWN multi-angle light scattering (SEC-MALS-IV) to derive the hydrodynamic radius, conformation, and branching ratio of a macromolecule in solution.
Key benefits of the microViscoStar:
SEC-IV without MALS?
Yes, as much as we love MALS for optimal polymer analysis, it's true that there are occasions when it just won't fit the bill.
Universal calibration is a parallel technique to SEC-MALS for determining molecular weight, commonly used to characterize linear polymers. While universal calibration overcomes some of the problematic issues associated with column calibration by reference molecules, it does not account for non-ideal column behavior caused by chemical solute-column interactions or hyperbranching.
Universal calibration is particularly-well suited to replace MALS for:
The Mark-Houwink-Sakurada relationship makes use of empirical relationships between intrinsic viscosity and molar mass, specific to each polymer and solvent, to estimate molar mass from SEC-IV measurements. Of course, the best way to determine MHS coefficients is to measure them using SEC-MALS-IV and ASTRA!