GPC/Light Scattering/Viscometry also known as Triple Detection GPC is the most comprehensive chromatography technique for polymer characterization. It employs Refractive Index Detector (with or without UV Detector), Dilute Solution Viscometry and Light Scattering all in series to determine molecular weights, distribution and related solution parameters. The triple detection GPC method is independent of calibration standards. Refractive Index Detector provides concentration profile and Refractive Index Increment (dn/dc), Light Scattering measures absolute Molecular Weight (MW) and Radius of Gyration (Rg), and Viscometer reveals Intrinsic Viscosity (i.e., molecular density) ([η]), Mark-Houwink-Sakurada Constants (α and KMHS), and Hydrodynamic Radius (Rh).
Intrinsic Viscosity, [η], a solution viscosity parameter, relates directly to the molecular mass of macromolecules in solution by the Mark-Houwink-Sakurada (M-H-S) equation: