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.

中文翻译：

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使用纳米纤维素增强3D打印的聚乳酸的机械性能

我们在这里报告对通过熔丝制造（FFF）3D打印处理的聚乳酸（PLA）与通过压缩成型处理的PLA的机械性能的系统研究。我们的结果表明，FFF-PLA的拉伸强度和模量分别比PLA压缩成型样品低49％和41％。我们还在此处演示了一种使用纳米纤维素增强3D打印PLA力学性能的方法。发现掺入少量（1wt％）的纤维素纳米纤维（CNF）分别将3D打印的PLA的拉伸强度和模量提高了84％和63％。X射线显微照相术用于探测3D打印的PLA和PLA / CNF复合材料的形态。与纯3D打印PLA相比，3D打印PLA / CNF复合材料的空隙明显更少。差示扫描量热法研究表明，CNF可以加速3D打印PLA的成核和结晶，从而提高结晶度。添加CNF不会影响3D打印PLA / CNF复合材料的热稳定性。3D打印的PLA / CNF复合材料的增强的机械性能可以归因于较高的结晶度和较少的缺陷。