Highly exfoliated eco-friendly thermoplastic starch (TPS)/poly (lactic acid)(PLA)/clay nanocomposites using unmodified nanoclay

• Biodegradable TPS/PLA/clay nanocomposites have been prepared by melt compounding.
• The unmodified NaMMT was highly exfoliated into the TPS matrix.
• A considerable decrease in water absorption was evident in the nanocomposites.
• The mechanical properties were highly improved in the nanocomposites.

Highly exfoliated, biodegradable thermoplastic starch (TPS)/polylactic acid (PLA)/sodium montmorillonite (NaMMT) nanocomposites were prepared by an eco-friendly approach, involving in-situ gelatinization of potato starch in presence of dispersed nanoclay followed by melt mixing with PLA. The morphological analysis revealed that the NaMMT was selectively dispersed into the TPS in a highly delaminated manner. An increase in mechanical as well as thermomechanical properties was evident in the presence of PLA and more influenced in the presence of clay. The water absorption was significantly decreased in the presence of PLA (∼8%) itself and both PLA and clay (∼8–12%) in the nanocomposites. The improved mechanical properties along with its biodegradability might lead to a new green material in the area of packaging.