Chromatographic and adsorption properties of poly(1-trimethylsilyl-1-propyne) and their stabilization by adding poly(1-phenyl-1-propyne)

Abstract

The chromatographic and adsorption properties of poly(1-trimethylsilyl-1-propyne) (PTMSP), a high permeable glassy polymer, were studied in the course of long-term usage of the Chromosorb P NAW+10wt% PTMSP adsorbent on a packed column in the temperature range of 30-180 °C. The structural changes in PTMSP related to a decrease in free volume and partial oxidation of the polymer were shown to substantially affect the adsorbent's properties. After the first 1.5 years (7000 h) of the column operation, the elution order of compounds changed, peak symmetry and efficiency of the column increased, the retention parameters as well as heats of adsorption of light hydrocarbons showed considerable changes. In order to stabilize the chromatographic properties of PTMSP, another disubstituted polyacetylene, poly(1-phenyl-1-propyne) (PPP), was added to the initial polymer, and a new mixed stationary phase, 97% PTMSP+3% PPP, was obtained and characterized. The resulting adsorbent, Chromosorb P NAW+10 wt% (97% PTMSP+3% PPP), is effective for solving a wide range of chromatographic problems, such as simultaneous detection of hydrocarbons and sulfur-containing inorganic gases, analysis of chlorine-substituted methanes in CCl4 and thiophene in benzene, separation of hydrocarbons and aromatic compounds. The chromatographic properties of the Chromosorb P NAW+10 wt% PTMSP (97% PTMSP+3% PPP) adsorbent were shown to remain stable in the course of its long-term operation (for at least 1.5 years, or 7000 h) on a packed column in the temperature range of 30-180 °C.