On investigation of flexural, morphological, and shape memory properties for 3D printed PLA-PVDF NFs-PLA interleave composite structures for smart gripper applications

Abstract

In the present study, the flexural, morphological, and shape memory properties of polylactic acid (PLA) matrix sandwiched with polyvinylidene difluoride (PVDF) Nanofibers (NFs) interleave composite structures have been investigated for applications of 4D printing such as smart grippers, and smart actuators. Firstly, an electrospinning process was carried out to form a PVDF NFs mat (thickness: 0.10–0.20 mm) under a flow rate of 3 µL/sec, an applied voltage of 12 kV, and a TCD of 100 mm. Further, the PVDF NFs mat was deposited in between the PLA layers, primed through fused filament fabrication (FFF) based 3D printing to manufacture the PLA-PVDF NFs-PLA based structures. In the next stage, the flexural properties were investigated for manufactured composite structures. The results highlight that the flexural strength of the composites was enhanced by 6.47% as compared to PLA. Results of the study are supported by a scanning electron microscope (SEM), X-ray diffraction (XRD), Fourier transform infrared (FTIR), V-I, V-R, and shape memory analysis. The finding of the study suggests that composite structures primed by higher mat thickness and zig-zag infill pattern have resulted in higher electrical resistance and better shape memory effect. However, increasing the voltage in the composite structure having higher mat thickness with a zig-zag fill pattern has resulted in a higher resistance drop.