Engineering PLA-MXene nanocomposite with balanced mechanical properties for enhanced shape memory effect

Abstract

Poly(lactic acid) (PLA) as shape memory material has gained attention due to its biocompatibility, biodegradability, and ease of processing by 3D printing. PLA's environmentally friendly nature makes it an attractive candidate for sustainable and recyclable shape memory applications. However, PLA's slow shape recovery rate and low shape fixation percentage hinder its applicability as shape memory material. In the present study, we report MXene-modified PLA (PLA/Mx) nanocomposite with enhanced shape memory effect. Solution processing methods mediated the loading of the MXene in the PLA matrix. Different samples were prepared by varying the weight% of the MXene in the PLA matrix. The structure and morphology of samples were analyzed by XRD and TEM characterization. Thermogravimetric analysis was performed to measure the thermal stability of the composite. Compared with pure PLA, with MXene loading, the PLA/Mx composites show an increase in thermal. The shape recovery study on PLA/Mx samples used temperature as an external stimulus. The PLA/Mx composite exhibited a significantly improved shape memory effect than the PLA alone. The study exhibits that a shape memory effect can be improved by tuning the MXene additive loading in the PLA matrix. The material shape recovery effect was validated by fabricating the spiral structure. The fast shape recovery time 3s and shape fixation/recovery of > 95% was observed for 1 wt% of PLA/Mx. The PLA/Mx composite is expected to contribute significantly to implementing innovative shape memory applications, particularly in the biomedical field for sutures, controlled drug release, and minimally invasive devices.