Epoxidized Palm Oil Plasticized Polylactic Acid/Fatty Nitrogen Compound Modified Clay Nanocomposites: Preparation and Characterization

Fatty nitrogen compounds (FNCs); fatty amides (FAs), fatty hydroxamic acids (FHAs), and N,N′-carbonyl difatty amides (CDFAs), which were synthesized from palm oil, have been used as organic compounds to modify a natural clay (sodium montmorillonite). The clay modification was carried out by stirring the clay particles in an aqueous solution of FAs, FHAs, or CDFAs by which the clay layer distance increased from 1.23 to 2.69, 2.89 and 3.21 nm, respectively. The modified clay was then used in the preparation of the epoxidized palm oil (EPO) plasticized polylactic acid (PLA) nanocomposites. The interaction of the modifier in the clay layer was characterized by X-ray diffractometry (XRD) and Fourier transform infrared spectroscopy (FTIR). Elemental analysis was used to estimate the presence of these FNCs in the clay. The nanocomposites were synthesized by solution casting of the modified clay and a PLA/EPO blend at the weight ratio of 80/20, which has the highest elongation at break. The nanocomposites were then characterized using XRD, transmission electron microscopy (TEM), thermogravimetric analysis (TGA), and tensile properties measurements. The XRD and TEM results confirmed the production of nanocomposites. PLA/EPO modified clay nanocomposites show higher thermal stability and significant improvement of mechanical properties in comparison with those of the PLA/EPO blend.