Conventional GPC Analysis

    Conventional GPC uses the response from the refractive index (concentration) detector alone and the comparative molecular weight data is obtained via a log molecular weight versus retention time calibration. The various organic solvent systems are normally calibrated with poly(styrene) or poly(methyl methacrylate) and the results are expressed as PS/PMMA equivalent molecular weights. For some common polymer types, a mathematical correction might be applied to express the results as for a specific polymer. For aqueous eluent systems, various calibrant polymer types are used.

    GPC with HFIP as the solvent is aimed specifically at the molecular weight characterization of polyamides and polyesters such as PET or PBT. Utilizing HFIP has been found to be appropriate for other difficult and complex polymer types including PEBAX and acetals.