Functionalized graphene nanoplatelets/poly (lactic acid)/chitosan nanocomposites: Mechanical, biodegradability, and electrical conductivity properties

Abstract

Abstract Different contents of functionalized graphene nanoplatelet (FGNP) were incorporated into the blend of poly (lactic acid)/chitosan (PLA/CS) (75/25 wt/wt), and the effect of nanoplatelet addition on mechanical properties, biodegradability behavior, and electrical conductivity of the blend was investigated. The results revealed the proper dispersion of FGNP in the blend, and the nanocomposite containing 3 phr FGNP (PLA75/CS25/FGNP3) demonstrated the finest morphology and the narrowest size distribution. The nanocomposite filled with 3 phr FGNP indicated an improvement of approximately 142% and 261% in tensile strength and Young's modulus, respectively, compared to the neat blend. Moreover, with the addition of 3 phr FGNP to the PLA/CS blend, thermal stability significantly improved. In addition, the study of biodegradability behavior demonstrated that the weight loss rate enhanced over time. From the fifth week onwards, the weight loss rate diminished because of the decrease in the number of degradable functional groups in the nanocomposite. On the other hand, the thermal conductivity of PLA75/CS25/FGNP3 showed an improvement of higher than 12 orders of magnitude compared to the neat blend. In addition, experimental data on electrical conductivity and power‐law model predictions were consistent.