@article {46836,
	title = {Enhancing the mechanical properties of 3D printed polylactic acid using nanocellulose},
	journal = {Polymer Engineering and Science},
	volume = {60},
	year = {2020},
	month = {AUG},
	pages = {1842-1855},
	type = {Article},
	abstract = {<p>We report here a systematic investigation of the mechanical properties of polylactic acid (PLA) processed by fused filament fabrication (FFF) 3D printing vs PLA processed by compression molding. Our results show that the tensile strength and modulus of FFF-PLA is 49\% and 41\% lower, respectively, than compression molded samples of PLA. We also demonstrate here an approach to augment the mechanical properties of 3D printed PLA using nanocellulose. Incorporation of a small quantity (1 wt\%) of cellulose nanofibers (CNF) was found to enhance the tensile strength and modulus of 3D printed PLA by 84\% and 63\%, respectively. X-ray microtomography was used to probe the morphology of 3D printed PLA and PLA/CNF composites. 3D printed PLA/CNF composites had significantly lesser voids as compared to neat 3D printed PLA. Differential scanning calorimetry study revealed that CNF can accelerate the nucleation and crystallization of 3D printed PLA leading to enhanced crystallinity. The thermal stability of 3D printed PLA/CNF composites was not compromised by the addition of CNF. The enhanced mechanical properties of 3D printed PLA/CNF composites can be ascribed to higher crystallinity and lesser defects.</p>
},
	keywords = {3D printing, Biocomposites, composites, fused filament fabrication (FFF), Nanocellulose, polylactic acid (PLA)},
	issn = {0032-3888},
	doi = {10.1002/pen.25421, Early Access Date = JUN 2020},
	author = {Ambone, Tushar and Torris, Arun and Shanmuganathan, Kadhiravan}
}
@article {48790,
	title = {Luminescent 3D printed poly(lactic acid) nanocomposites with enhanced mechanical properties},
	journal = {Polymer Engineering and Science},
	volume = {63},
	year = {2023},
	month = {JUL},
	pages = {2059-2072},
	type = {Article},
	abstract = {<p>
	The three-dimensional (3D) printing of functional composite materials has gained tremendous interest in recent years. Nevertheless, research on 3D printing of luminescent composite materials is very limited, and the mechanical properties of such 3D-printed composites are poor. Herein, we report the preparation and characterization of a poly(lactic acid) (PLA) composite that, when 3D printed, exhibits enhanced toughness and high solid-state fluorescence quantum yield. Incorporation of only 1 wt\% pyrene butyric acid modified cellulose nanofibers (PBA-m-CNF) and l0 wt\% thermoplastic polyurethane (TPU) into PLA led to 223\% increase in toughness and 21\% increase in tensile modulus of PLA. Scanning electron microscopy (SEM) and X-ray microcomputed tomography (mu-CT) analysis of the fractured cross-sections of 3D printed composites revealed a ductile failure mode. The PLA/PBA-m-CNF1/TPU10 3D printed composite also exhibited a high solid-state fluorescence quantum yield of 38.35\%. To the best of our knowledge, this is the first report to show both enhanced mechanical properties and high solid-state fluorescence emission for 3D printable PLA. Such functional PLA composites could have potential applications in the fabrication of complex-shaped sensors, optical light pipes, etc.</p>
},
	keywords = {3D printing, Composite, fluorescence, Nanocellulose, poly(lactic acid), toughness},
	issn = {0032-3888},
	doi = {10.1002/pen.26345},
	author = {Kothavade, Premkumar Anil and Yadav, Prashant and Nidhankar, Aakash D. and Torris, Arun and Pol, Harshawardhan and Kafi, Abdullah and Bateman, Stuart and Sukumaran, Santosh Babu and Shanmuganathan, Kadhiravan}
}
