Optimum loading level of nanoclay in PLA nanocomposites

Abstract

Biodegradable polymer nanocomposites of poly(lactic acid) and nanoclay (Cloisite 30B) samples were prepared with compositions of 0%, 1%, 2%, 3%, 4%, and 5% (by mass) nanoclay using extrusion followed by injection molding. An exfoliated morphology was observed using x-ray diffraction. The nanocomposites were investigated for their mechanical properties using dynamic mechanical analysis (DMA) and tensile testing. The combination with 3% nanoclay was found to be optimum as a result of having the greatest mechanical strength. The fracture surfaces of the samples were also observed with the help of a scanning electron microscopy, and the images obtained complied with the experimental values attained for the samples, indicating more ductile fractures for those samples with greater mechanical strength. The thermal properties of the composites were studied with the help of differential scanning calorimetry and DMA data, and it was found that the trend followed by the glass transition temperature values obtained by both the methods was the same.