Preparation and characterization of PLA/PBAT/CNC blend nanocomposites

Abstract

In this study, the effect of cellulose nanocrystals (CNCs) on the properties of polylactide (PLA)/poly(butylene adipate-co-terephthalate) (PBAT) blends was investigated. Samples were prepared via (i) solution casting (SC) and (ii) combination of solution casting and melt mixing through twin-screw extruder (mTSE). Scanning electron microscopy images revealed the effect of CNC content on the droplet morphology of PBAT dispersed phase. Rheological analysis showed that 3 wt% of CNC formed a strong network in PLA by SC method. Differential scanning calorimetry results depicted the heterogeneous nucleation effect of CNC on PLA's crystallization in samples prepared by mTSE. Dynamic mechanical analysis illustrated that CNC enhanced the modulus beyond the glass transition temperature of PLA regardless of the preparation method. The tensile and impact properties also elucidated that the existence of any possible residual solvent in blends could dramatically avoid achievement of improvements in ductility and impact properties.