A comparative study of structure, thermal degradation, and combustion behavior of starch from different plant sources

The present study investigated the structure, degradation properties, and combustion behavior of starch from maize, sweet potato, lotus root, and tobacco. Compared with other plant starches, tobacco starch had the smallest size, the highest amylose content and the least crystallinity. Microscale combustion calorimetry (MCC) experiment demonstrated that sweet potato starch showed the maximum peak heat release rate value (888.0 W g(-1)) while tobacco starch showed the minimum value (316.0 W g(-1)) and thermogravimetric analysis coupled with Fourier transform infrared spectrometer (TG-FTIR) results showed tobacco starch had good char formability (residue mass: 15.6%) and released more incombustible gaseous products, such as H2O and CO2. These results suggest that the thermal properties of plant starches were mainly influenced by the structural features and amylose content, especially the amylose ratio, and tobacco starch was very promising for application in green flame-retardant material.