Thermal stability of poly[1‐(trimethylsilyl)‐1‐propyne] and the gas chromatographic stationary phase based on it

Abstract

The thermal stability of poly[1-(trimethylsilyl)-1-propyne] is investigated by heating the capillary column with this polymer as the stationary phase with the subsequent separation of the test mixture of light hydrocarbons. It is shown that heating of the column up to 130°C does not cause a decrease in efficiency or in the retention time of solutes. A further increase in temperature results in both decrease in column efficiency and sorbate retention. However, a decrease in column retentivity goes in one way for all the tested hydrocarbons. At the same time, the efficiency of the column is changed to a lesser degree for methane and ethane up to the temperature of polymer degradation, while for propane, butane, and iso-butane the difference is rather sharp. The most expressed decrease in efficiency was found for iso-butane: the column efficiency for this sorbate versus temperature of heating had two stages. The diffusion coefficients for sorbates in the polymeric phase were also evaluated and the sharp decrease in their values was found after the column heating.

Preparation and properties of GC capillary column with hypercrosslinked stationary phase

“…Formation of porous layer by MPIP polymers occurs due to nonregular organization of rigid MPIP molecules [18]. However, polymeric molecules in solid polymer tend to pack more densely with the time and to decrease nonequilibrium free volume [19]. This process is called "physical aging" and negatively affects chromatographic properties of PLOT column [20].…”