Influence of electron beam radiation on structural and mechanical performance of thermoplastic cassava starch

This study aims to investigate changes in the structural, morphological, thermal and mechanical properties of thermoplastic cassava starch caused by electron beam radiation at 25, 50, 75 and 100 kGy. The influence of electron beam radiation increased moisture resistivity by up to 10% compared to unirradiated thermoplastic cassava starch. Electron beam radiation also induced crosslinking formation, shown by the increase in normalized gel mass fraction. Furthermore, the tensile and thermal properties improved, as did the strength of the irradiated thermoplastic cassava starch; this improved by up to 3.2 MPa, respectively at 25 kGy. Structural findings based on the FTIR analysis showed the formation of carboxylate and carbonyl groups after the irradiation process. Despite this, the morphological analysis from the SEM showed a smooth and less granular formation upon the electron beam radiation. This is due to the fragmentation and dissolution of the cassava starch granule from the electron beam radiation. Hence, this study concludes that the electron beam radiation improved performance of the thermoplastic cassava starch by the radiation inducing a crosslinking formation.