Thermogravimetric analysis of developing cotton fibers

In this research, thermogravimetric analysis (TGA) was used to investigate the structural changes that occur during cotton fiber development starting at 10 days post-anthesis (dpa). The percent weight losses attributed to water, non-cellulosic materials, and cellulose macromolecules were calculated from the thermograms. Valuable information was obtained related to the composition of the cell wall and the timing of the transition between the primary cell wall and the secondary cell wall. The results indicated that the two cultivars investigated (TX19 and TX55) exhibited different structural evolution. The transition phase between the primary cell wall and the secondary cell wall occurs between 17 and 18 dpa in fibers from the TX19 cultivar, while this transition occurs between 21 and 24 dpa for fibers from the TX55 cultivar. These conclusions are in agreement with the results obtained with Fourier transform infrared spectroscopy.