Gas Chromatography and Thermodynamic Characteristics of the Sorption of Model Sorbates on New Stationary Phases Based on Poly[oligo(ethylene glycol)diacrylates]

Resumo

The thermodynamic parameters of sorption of a test mixture of hydrocarbons on a new type of PEG-like stationary phases are determined from the temperature dependence of sorbate retention in the temperature range of 35–110°C. The determined entropy and enthalpy of sorption are close for all the studied stationary phases, despite the different ratios of ethylene glycol and acrylate moieties in the polymer’s phase structure. At the same time, the studied phases exhibit greatly different separation abilities, due apparently to the kinetic properties of the phases, as is indicated by differences in the efficiency of the columns with these phases and in the diffusion coefficients of sorbates on these phases.