Biobased polylactide (PLA) nanocomposites

Three types of polylactide (PLA) composites, namely, PLA/nanoclay, PLA/core-shell rubber, and PLA/nanoclay/core-shell rubber were melt compounded via a co-rotating twin-screw extruder. The effects of two types of organically modified nanoclay (i.e., Cloisite®30B and 20A), two types of core-shell rubber (i.e., Paraloid EXL2330 and EXL2314), and the combination of nanoclay and rubber on the mechanical properties of the composites were investigated. In comparison with pure PLA, both types of PLA/5wt% nanoclay composites showed an increased modulus, a slightly reduced tensile strength, a similar impact strength, and a significantly reduced strain at break. PLA/EXL2330 composites with a rubber loading level of 10wt% or higher exhibited much higher impact strength but lower modulus and strength when compared to pure PLA. The simultaneous addition of 5wt% nanoclay (Cloisite®30B) and 20wt% EXL2330 resulted in a PLA composite with a 134% increase in impact strength, a 6% increase in strain at break, a similar modulus, and a 28% reduction in tensile strength as compared to pure PLA.