ZnO nanoparticle-grafted PLA thermoplastic composites for 3D printing applications: Tuning of thermal, mechanical, morphological and shape memory effect

Abstract

The zinc oxide (ZnO)-grafted polymers have emerged as a prominent material for fabrication of 3D printed biosensor due to its inherent antibacterial, antifungal, room temperature ferromagnetic magnetic behaviour, crystallinity, high thermal conductivity and high exaction binding energy. In this study, ZnO (nanoparticles (NPs)) were grafted with polylactic acid (PLA) using twin-screw compounder for preparations of feedstock filaments. The filaments were prepared by varying input parameters of twin-screw compounder such as ZnO concentration in PLA (0–2%), forced loading (10–15 kg) and torque (0.1–0.2 Nm). Further tests were conducted for thermal properties (on differential scanning calorimetry set-up), mechanical properties (on ultimate tensile testing set-up, Shore D surface hardness, optical photomicrograph-based porosity analysis) and shape memory effect (with stimulus as water under different temperature conditions). The results of the study show that inducing 1% ZnO in PLA led to the formation of highly responsive composite with water as stimulus (at 25°C temperature), mechanically weak, porous, soft surface, while incorporation of 2% ZnO in PLA headed to less porous, harder and responsive composite to the water as stimulus (at 40°C temperature). The proposed combination of ZnO NPs and PLA shows encouraging range of crystallinity, tensile properties and shape memory effect, which made it an eligible candidate for 3D printing applications.

Exploring the Journey of Zinc Oxide Nanoparticles (ZnO-NPs) toward Biomedical Applications

“…This observation led to the development of a 3D printed customized wound-healing template made of ZnO-NPs that were uniformly scattered within an alginate template, which can be easily created and contour-printed to the exact size and depth of a wound. 3D printing consist of the adding of material layer by layer, allowing for the fabrication of unique shapes and customizability, which are crucial in biomedical areas such as tissue engineering and pharmaceuticals [ 141 ].…”

Investigation of the Shape-Memory Properties of 3D Printed PLA Structures with Different Infills

“…The mechanical properties of the most often used polymers, such as PLA or acrylonitrile butadiene styrene (ABS), and the surface waviness are often the factors limiting possible applications [ 11 , 12 , 13 , 14 ]. Several research groups thus aim at increasing the mechanical properties, e.g., by embedding nanoparticles, nanofibers, microfibers, chemical or heat treatment [ 15 , 16 , 17 ]. Alternatively, PLA or also flexible FDM polymers can be used to create sandwiches with other objects, e.g., with textile fabrics which can be used to increase the elastic modulus [ 18 , 19 , 20 ].…”

Pressure Orientation-Dependent Recovery of 3D-Printed PLA Objects with Varying Infill Degree

“…On the other hand, the most frequently used 3D printing materials for the fused deposition modeling (FDM) technique, i.e., acrylonitrile butadiene styrene (ABS), poly(lactic acid) (PLA) and a few others, often cannot reach the desired mechanical properties and the low surface roughness and waviness which are necessary in some applications [ 7 , 8 , 9 ]. Typically, the reduced mechanical properties are counteracted by heat post-treatments, by integrating nanofibers or nanoparticles [ 10 , 11 , 12 ] or continuous fibers [ 13 , 14 ].…”