ViscoStar Differential Viscometer for GPC

The ViscoStar^® is an on-line differential viscometer for GPC that measures the intrinsic viscosity (IV) of polymers. It is best used in conjunction with the DAWN^® or miniDAWN^® multi-angle light scattering (MALS) detectors in SEC-MALS-IV analysis to determine absolute molar mass, size, molecular conformation, branching ratio and Mark-Houwink parameters.

The ViscoStar may also be used for traditional online IV applications, such as Universal Calibration or Mark-Houwink analyses of molecular weight and size, all supported by Wyatt’s ASTRA^® chromatography software.

The ViscoStar incorporates several innovations that make it the most advanced differential viscometer available: automated thermal bridge tuning to ensure perfect bridge balance every run, a patented pump pulse suppression system that eliminates pressure fluctuations due to the GPC pump without loss of chromatographic resolution, and dual-Peltier thermal control for optimal isolation of the temperature-sensitive bridge from room temperature variations.

Features

Sensitivity: 100 ng of 100 kDa polystyrene in THF at 1 mL/min, with a standard 7.8 x 300 mm GPC column

Differential pressure noise: < 0.05 Pa

Differential pressure range: 6.9 kPa

Dynamic range: 135,000:1 for measuring small and large peaks simultaneously

Solvent compatibility: compatible with most aqueous and organic solvents

Capillary bridge autobalance: 10-min thermal, leak-free mechanism

Delay volumes: 8.1, 5.4 or 2.7 mL standard; 16.2 mL optional

Temperature control: 4 – 70 °C

Touch-panel display for immediate access to data, diagnostics and settings

Software: ASTRA chromatography software provides comprehensive analyses and user-friendly features including HPLC control, “One-click MW” and user-designed reports. Optional 21CFR11 support for GMP.

Applications

Polymers: absolute molar mass and size (distributions and moments), conformation and branching, Mark-Houwink parameter determination

Linear or branched polymers, co-polymers

Polymers not amenable to SEC-MALS analysis dissolved in semi-opaque or refractive-index-matched solvents, or polymers that fluoresce at the MALS laser wavelength

Most aqueous and organic solvents