Thermally stimulated currents (TSCs) of Langmuir-Blodgett films

This paper describes the thermally stimulated currents (TSCs) of acidic (AA) and polyamic acid alkylamine salts (PAAS) Langmuir-Blodgett (LB) films. The measurements were performed from room temperature to about 250°C and the temperature was increased at a rate of 0.02°C/s linearly. Peaks of TSCs are observed at about 80°C in the arachidic acid LB films and at about 80°C and 16°C in the PAAS LB films. They indicate that the peak at 80°C is resulted from alkyl group, and the other peak at 160°C is due to alkyl and C-O group in PAAS molecules. The additional large peak at about 160°C is due to dipole moments of the PAAS molecules. Differential scanning calorimetry (DSC) and thermogravimetric analysis (TGA) of the PAAS and arachidic acid molecules were measured and analyzed