End-functionalized polyethylene oxide coated silica particles for packed capillary column supercritical fluid chromatography

Surface-Initiated Radical Polymerization on Porous Silica

“…8 This method has also found use in supercritical fluid chromatography, where the reduced porosity of the silica gel decreases zone broadening and analysis time; 9 however, degradation of the polymer film can occur under the harsh condition in supercritical fluids. 10 The second method is to graft polymers to the surface by forming a covalent bond between the polymer and the surface. This has been accomplished in many ways, including the use of thiol-derivatized polymer for grafting to gold, 11 the grafting of peptides 12 and dendritic polymers 13 through an amide linkage to the surface, and attaching a silane coupling agent to the terminus of a polymer to allow grafting to a silica surface.…”

Synthesis and Evaluation of an Aromatic Polymer-Coated Zirconia for Reversed-Phase Liquid Chromatography

“…The best way to combine rigid and porous metal oxides with versatile organic polymers is to make a material comprised of an inorganic skeleton modified by either a physically sorbed or chemically bonded polymer layer. Polybutadiene, , polystyrene, − poly(ethylene oxide), and polysiloxane , are often used for coating metal oxides. Schomburg developed a method to coat polybutadiene on silica, and the resulting stationary phase gave excellent chromatographic separations .…”

Performance of polyethylenimine-coated particles in packed capillary column supercritical fluid chromatography

“…Figure 2 shows the results obtained with these Sidiol-HMDS-PEI particles. Although some improvements in peak shape and retention were obtained, the a-phenylethylamines still showed severe peak tailing, which was much worse than that obtained _2c 100 220 atm with a capillary column packed with diol-bonded and PEO-NH,-coated particles [5]. These results suggest that the N-H groups in the repeatable units of the PEI molecular chains interact with the alkylamines.…”

“…4) such as a-phenylethylamines, which permanently remained in the column. It was also found that coating other basic polymers such as aminoterminated polyethylene oxides (PEO-NH,) on the diol-bonded silica surface could modify the particle surface suitable for analyzing alkylamines [5]. This modification contributed to a neutralizing interaction between the basic NH, group in the PEO-NH, polymer and the acidic residual silanol groups on the bonded silica surface.…”

“…4). The previous study also demonstrated that basic aminoterminated polyethylene oxide (PEO-NH,) coated particles could be used for the separation of alkylamines [5]. However, unacceptable peak tailing of primary alkylamines and the limited stability of the PEO-NH, coating necessitates further study of basic polymer-coated particles.…”