Gel Permeation Chromatography (GPC) is a separation method for the determination of molecular weight averages (Mn) and molecular weight distribution (PDI=Mw/Mn). The testing report can include calibration plot, chromatogram, number average molecular weight and PDI of the polymer.
GPC separates molecules on the basis of hydrodynamic size rather than molecular weight. The large molecules move more rapidly through the GPC column, and in this way the mixture can be separated. The elution volume of a molecule is related to its hydrodynamic volume. To relate the elution volume to the molecular weight of a polymer, a calibration with molecular weight standards is needed.
- Solvent: trichlorobenzene (TCB)
- MW range: 100-1,000,000 Da
- Temperature range: 40-220°C
- Suitable for high temperature polymers (such as polyolefins)
- Calibration standard: polystyrene (PS)
- Detector: refractive index (RI)