Analysis of adsorption energy distribution in selected hydrophilic-interaction chromatography systems with amide, amine, and zwitterionic stationary phases.

Adsorption mechanisms of caffeine, quercetin, and phenol as test substances in various chromatographic systems have been analyzed. The investigations were conducted using three different chromatographic columns packed with polar bonded stationary phases, that is, amide, amine, and zwitterionic. Methanol-water and acetonitrile-water systems with different organic solvent contents have been used as mobile phases.

Brillouin study of photopolymerization process of two-monomer systems.

The results of Brillouin scattering investigations of two-component system: 2,2-bis[4-(2-hydroxy-3-methacryloxypropoxy)phenyl]propane/polyethylene glycol methacrylate (bis-GMA/PEGMM) containing 0, 30, 50, 70, 85 and 100 mol% of PEGMM are presented. For the first time the Brillouin spectroscopy was used to monitor the progress of the polymerization process. The polymerization was initiated by ultraviolet radiation (λ=365 nm), at temperature 20°C and 40°C.

Elastic properties of some selected two-monomer systems as studied by Brillouin spectroscopy.

We present results obtained by Brillouin scattering method for four two-component systems comprising of a high viscosity monomer and a low viscosity monomer. The monomers used were crosslinking (divinyl) or linear (monovinyl) ones. The investigated systems were: divinyl/divinyl-bis-GMA/TEGDM; divinyl/monovinyl-bis-GMA/PEGMM; monovinyl/divinyl-bis-MGMA/TEGDM and monovinyl/monovinyl-bis-MGMA/PEGMM; they were formulated at various molar ratios.