Fused filament fabrication of biodegradable polylactic acid reinforced by nanoclay as a potential biomedical material

Abstract

Fused filament fabrication (FFF) is one of the most common 3D printing techniques having considerable potential in various fields such as pharmaceutical, medical, aerospace, and automotive. One of the impediments of FFF components is their lower mechanical performance compared with those from conventional fabrication methods. This work aims to investigate the effect of adding nanoclay due to being nontoxic to the biodegradable polylactic acid (PLA) polymer matrix for medical applications. PLA granules were melt-compounded by a twin-screw extruder with nanoclay at 2 and 4 wt.%, and then, PLA and PLA/nanoclay filaments were produced using a single-screw extruder. An L9 orthogonal array of the Taguchi approach was utilized as the design of the experiment tool to study the process in detail considering nanoclay content, nozzle temperature and raster angle as material and processing parameters. The dispersion of nanoclay in the PLA matrix was assessed by X-ray diffraction test. The results indicated that the tensile strength was enhanced by 4.6% and 15.3% using the addition of 2 and 4 wt.% of nanoclay, respectively. The microscopic observations showed that the bonding between the rasters and between the contours and rasters was improved by increasing the temperature, and consequently, led to higher tensile strength values. The results revealed that the tensile strength of 38.9 MPa was obtained at the optimum condition.