Comparison of the effects of calcified green macroalga (Halimeda macroloba Decaisne) and commercial CaCO3 on the properties of composite starch foam trays

The calcified green macroalga, Halimeda macroloba, is a source of bio-based calcium carbonate which can be used as a filler in starch foam tray. In the first part of this study, the composition and structure of calcium carbonate of this species were investigated using Fourier transform infrared spectrometry (FTIR), X-ray diffraction (XRD), Energy dispersive X-ray spectroscopy (EDX) and Scanning election microscopy (SEM). The morphology of the macroalgal powder particles was rod-like and organic materials (e.g. polysaccharide) and calcium carbonate (aragonite form) were present. The second part of the study investigated the effects of calcium carbonate from H. macroloba on the properties of starch foam tray and compared them with the properties of starch foam tray filled with commercial CaCO3. Interestingly, the composites starch foam trays with macroalgal powder had better impact strength than starch/commercial CaCO3 composite foam trays. Moreover, the macroalgal powder affected the thermal properties of the starch foam tray equally as well as commercial CaCO3. However, the macroalgal powder caused more significant changes in the color parameters and the whiteness values of starch foam tray than commercial CaCO3.