Investigation on Glass Transition Temperature of fillers in the marine sector

This study investigates the thermal behavior of three different epoxy-based marine fillers via DSC. Tg was measured using three methods: inflection point (Tgi), half-step height (Tg1/2), and equal-area method (Tga) in a range –50 °C and 100°C or –50 °C and 170 °C. The evaluation of the mean values and standard deviations of the Tg in the second scan showed a fair variability of the obtained data, and the impossibility of finding a precise correlation between them, being variable with the changing of the analyzed samples. The methods for the calculation of Tg1/2 and Tga give significantly different values depending on the change of the temperature intervals for the calculation of the baselines; on the other hand, the value of Tgi are more stable. Care must be taken about the temperature range of the first scan, in order not to alter, with too high final temperatures, the structure of the material.