Studies on the physicochemical properties of modified starch-based wood nanocomposites

Bio-based nanocomposites were prepared from starch and soft wood with water as the solvent via a green route with great engineering aspects. Methyl methacrylate (MMA) modified starch, dimethyloldihydroxyethyleneurea (DMDHEU), wood flour, glycerol, and montmorillonite clay (MMT) were employed to prepare the wood starch nanocomposites (WSNC). Three different percentages of MMT were employed to prepare the starch composites and the properties of MMT modified starch composites were studied through limiting oxygen index test (LOI), mechanical and thermogravimetric analysis (TGA). The delamination of silicate layers and morphology of clay incorporated nanocomposites were explained by X-ray diffractometry (XRD), scanning electron microscopy (SEM), and transmission electron microscopy (TEM). WSNC with 3 phr (parts per hundred) MMT showed better properties compared to composites containing 1 and 5 phr MMT. The nanocomposites with 3 phr MMT enhanced the flexural strength and tensile strength by 28% and 112%, respectively, compared to MMT free composites. The WSNC having 3 phr MMT also exhibited an outstanding improvement in thermal stability, water resistance, and flame retardancy properties.