Microcrystalline cellulose reinforced polylactic acid biocomposite filaments for 3D printing

The aim of this study was to produce a novel microcrystalline cellulose (MCC) reinforced polylactic acid (PLA), fully degradable biocomposites for 3D printing applications. The biocomposites were produced in filament form by solvent casting and twin screw extrusion to achieve final concentrations of 1, 3, and 5 wt% of cellulose. In order to improve compatibility with the PLA, the cellulose was surface-modified using a titanate coupling agent. Influence of cellulose content and modification on the morphological, mechanical, and thermal properties of the biocomposites were studied. Differential scanning calorimetry results reveal an increase in crystallinity for all biocomposites, with 3 wt% surface-modified cellulose displaying highest values. Dynamic mechanical thermal analysis results show that storage modulus increased for all biocomposites when compared with neat PLA, with the most significant increase associated with the 3 wt% modified cellulose. The surface modification of cellulose shifted the tan delta peak of the 1 and 3 wt% biocomposite toward lower temperatures, indicating an increased mobility of the PLA chains. Finally, the extruded cellulose reinforced PLA filaments were successfully 3D printed using a fused deposition modeling technique. POLYM. COMPOS., 39:1311-1320, 2018. (c) 2016 Society of Plastics Engineers