Director, Materials Characterization Lab
The Waters gel permeation chromatograph (GPC) is used to analyze the size of polymers based on their speed of sieving through a series of divinylbenzene (DVB) columns with different pore sizes. The polymers can then be detected or characterized by their alteration of the refractive index of the solvent and/or by their ability to scatter laser light. Refractive index detection is performed with a Waters 2414 differential refractive index detector while laser light scattering is performed using a Wyatt Dawn EOS multi-angle light scattering detector. The later has 18 detectors at different angles around the flow cell and can be used to determine the absolute size distribution of polydisperse samples as well as the radius of gyration (Rg). The instrument is mainteined with tetrahydrofuran (THF) as the primary solvent but can also be operated with chloroform with advanced notice.