Study of changes in polymer-probe interactions with stabilization temperature of a column contained polyacrylonitrile by using inverse gas chromatography

A column filled with chromosorb W (45-60 mesh) coated with polyacrylonitrile (PAN) was conditioned at different temperature, 150, 175, 200, 225, 260, and 275degreesC under nitrogen current. After each stabilization the specific retention volumes, V-g(0), of probes were determined by using inverse gas chromatography (IGC) techniques for acetone, acetonitrile, p-xylene, n-propanol, pyridine, and n-hexane as probes in the temperature range 50-150degreesC. When temperature changed from 150 to 275degreesC specific retention volumes, V-g(0), and values of probes were increased. Also, V-g(0) values of polar probes were higher than those of unpolar probes. A film of PAN homopolymer was heated in an oven at 150, 175, 200, 225, 260, and 275degreesC under nitrogen current (the conditions are the same as those of coated PAN in the column). After each heating event, PAN films were used for Fourier transform infrared spectroscopy (FT-IR) measurements. The FT-IR spectra of PAN film (when temperature increased from 150 to 275degreesC), showed some new peaks at the 740-3350cm(-1) region and increased intensity of some peaks between 2900-3500cm(-1) and 1100-1700cm(-1). According to differential scanning calorimeter (DSC) analysis, the glass transition temperature of PAN found to be 130degreesC.