Anh Mai Nguyen

Preparation of Macroporous Monoliths for Use in Liquid Chromatography: New Approaches Anh Mai Nguyen

High performance liquid chromatogarphy (HPLC) is one of the major techniques in separation sciences. Faster separation and higher efficiency are required to meet ever-growing demands. Despite numerous efforts on improving mass transfer in particulate packings discontinuity seems to be the cornerstone. Macroporous continuous beds or monoliths are, therefore, a promising alternative to the particle medium. The work deals with the preparation of new monoliths used as support for HPLC stationary phase. Two different approaches were developed: one based on the polycondensation of epoxy resins which were dispersed in aqueous polyamine phase with the aid of a surfactant. The other involved a traverse of linear polyamides solutions around their upper critical solution temperatures (UCST). The polymers, dissolved in a solvent at temperatures higher than their UCSTs followed by slow cooling to below these temperatures to precipitate the polymers. Partly re-established hydrogen bonds resulted in the formation of crystallites that interconnected into a network structure. The study also deals with surface modifying for chromatographic applications.