Surface characterization of chitin by inverse gas chromatography

The surface properties of a chitin (degree of deacetylation was 33.6%) were quantificationally analyzed by inverse gas chromatography (IGC) in this work. Four n-alkanes (C5, C6, C7, and C8) were chosen as apolar probes to characterize the dispersive component of free energy. Trichloromethane (CHCl3), acetone, ether and tetrahydrofuran (THF) were chosen as polar probes to detect the Lewis acid–base parameters. It was found the dispersive component of free energy was 37.58, 42.12, 45.70, and 51.69 mJ/m2 at 40, 50, 60, and 70 °C, respectively. The Lewis acidic number Ka was 0.0793, and the basic number Kb was 0.7936. The result means the chitin is a Lewis basic polymer.