Poly(lactic acid) and layered silicate nanocomposites prepared by melt mixing: Thermomechanical and morphological properties

Poly(lactic acid) (PLA) nanocomposites were prepared by melt mixing technique in a Haake batch mixer. The clay dispersion within the PLA matrix during melt mixing was well explained through the morphological characterization. Morphological characterizations were studied by X-ray diffraction and transmission electron microscopy. The exfoliation/intercalation of the clay particles within the polymer matrix during melt mixing depends on the mixing torque generated during the preparation of nanocomposites. The significance of processing temperature and the mixing time in melt mixing were studied for PLA/C93A and PLA/C30B nanocomposites. The structure and properties of the nanocomposites were also characterized by differential scanning calorimetry, thermogravimetric analysis, dynamic mechanical analysis, and mechanical properties by standard tensile testing. The incorporation of nanoclays into the PLA matrix enhanced the mechanical properties and thermal stability of the PLA nanocomposites. This may be due to the reinforcing effect of nanoclays within the polymer matrix. POLYM. COMPOS., 2012. (C) 2012 Society of Plastics Engineers