Mechanical, Thermal and Morphological Properties of Injection Molded Poly(lactic acid)/Calcium Carbonate Nanocomposites

Abstract

In this work, mechanical and thermal properties of maleated ethylene-propylene rubber (EPR-g-MAH) toughened poly(lactic acid) (PLA)/nano-precipitated calcium carbonate (NPCC) nanocomposites were investigated. It was found that elongation at break of PLA/NPCC was increased with increasing EPR-g-MAH content up to 15 phr (parts per hundred resin). The investigations on the crystallization behaviours demonstrated that the NPCC acted as nucleating agent for the PLA. However, the degree of crystallinity of PLA was reduced by the addition of EPR-g-MAH which appears to be due to encapsulation of NPCC by the maleated rubber. Dispersion of NPCC was observed using transmission electron microscopy (TEM), and it was revealed that both nano-dispersed and agglomerates NPCC exist in the PLA matrix. Moreover, encapsulation of NPCC was favored in the presence of EPR-g-MAH.