Influence of nanofibrillated cellulose on the mechanical and thermal properties of poly(lactic acid)

Abstract

In this work, we used a twin-screw extruder – as an alternative to other, more energy-intensive mechanical methods – to produce nanofibrillated cellulose. Scanning electron microscopy and thermogravimetric analysis were employed to determine morphology and thermal properties of the nanofibrillated cellulose. Further, we prepared poly(lactic acid)/nanofibrillated cellulose (PLA/NFC) composites by melt blending followed by injection molding, and subsequently characterized them using mechanical testing, size exclusion chromatography and differential scanning calorimetry. Our results showed that nanofibrillated cellulose produced in a twin-screw extruder can be used as reinforcement for poly(lactic acid). Adding only 5 wt% nanofibrillated cellulose yielded improvements in the crystallization behavior of PLA. An increase in elastic modulus was observed for all PLA/NFC composites compared to neat PLA.