Studies of poly(lactic acid) based calcium carbonate nanocomposites

The effect of nano-calcium carbonate on chain linked poly(lactic acid) was investigated. In order to improve inorganic nanofillers/polymer compatibility CaCO3 nanoparticle surface was treated by stearic acid. The nanocomposites were prepared by means of solution blending and further studied by using dynamic mechanical analysis, fourier transform infrared spectroscopy, scanning electron microscopy and thermogravimetric analysis. Morphological analysis performed on nanocomposites fractured surfaces has revealed that the CaCO3 modification induces homogeneous and fine dispersion of nanoparticles into polymer as well as strong interfacial adhesion between the two phases. An increase in the Tg and storage modulus of the resulting nanocomposites was observed with the increase of calcium carbonate ratio. Thermogravimetric results showed a lower degradation temperature with the increase of calciium carbonate ration in the polymer matrix.