Magnetically activated 3D printable polylactic acid/polycaprolactone/magnetite composites for magnetic induction heating generation

Abstract

Additive manufacturing technology has attracted the attention of industrial and technological sectors due to the versatility of the design and the easy manufacture of structural and functional elements based on composite materials. The embedding of magnetic nanoparticles in the polymeric matrix enables the development of an easy manufacturing process of low-cost magnetically active novel polymeric composites. In this work, we report a series of magnetic composites prepared by solution casting method combining 5 to 60 wt.% of 140 $$\pm$$ ± 50 nm commercial Fe3O4 nanoparticles, with a semi-crystalline, biocompatible, and biodegradable polymeric blend made of polylactic acid (PLA) and polycaprolactone (PCL). The composites were extruded, obtaining 1.5 $$\pm$$ ± 0.2 mm diameter continuous and flexible filaments for fused deposition modelling 3D printing. The chemical, magnetic, and calorimetric properties of the obtained filaments were investigated by differential scanning calorimetry, thermogravimetric analysis, magnetometry, and scanning electron microscopy. Furthermore, taking advantage of the magnetic character of the filaments, their capability to generate heat under the application of low-frequency alternating magnetic fields (magnetic induction heating) was analyzed. The obtained results expose the versatility of these easy manufacturing and low-cost filaments, where selecting a desired composition, the heating capacity can be properly adjusted for those applications where magnetic induction plays a key role (i.e., magnetic hyperthermia, drug release, heterogeneous catalysis, water electrolysis, gas capture, or materials synthesis). Graphical Abstract This paper presents the manufacture of novel magnetically activated 3D printable filaments, low cost and easy to manufacture, whereby selecting the desired composition, the heating capacity (ρ) generated under the application of an alternating magnetic field (Happ) can be adjusted to the needs of the user.

3D-printable composites for magnetic refrigeration based on Ni-Mn-In-Co magnetic shape memory alloys

“…A considerable shift of the PCL decomposition to lower temperatures is, in turn, observed as a consequence of the addition of MPs. This is in accordance with previous results [31,42,43] where the increase in the pyrolysis of PCL chains has been ascribed to the limitation of the movement of polymeric chains caused by the incorporation of magnetic particles. Nevertheless, the composite decomposition is well above the usual printing temperatures in FDM 3D printing, so no influence whatsoever is expected in any elaboration or operation step.…”

“…As indicated, the very large endothermic peak observed around 330 K corresponds to the melting of the PCL matrix whereas the exothermic one around 300 K is linked to the polymer crystallization taking place on subsequent cooling. The calculated enthalpies for melting and crystallization in the composite are 25.0 J/g and 26.4 J/g, respectively, which in both cases represent around 38% of the pure PCL enthalpies (∆𝐻 𝑚𝑒𝑙𝑡 𝑃𝐶𝐿 = 66𝐽/𝑔 and ∆𝐻 𝑐𝑟𝑦𝑠𝑡 𝑃𝐶𝐿 = 69𝐽/𝑔 [31]), a slightly higher value than the nominal 30% PCL weight concentration. On the other hand, the much smaller enthalpy change associated to the MT in the metallic MPs (~ 20 times lower) makes the corresponding peaks to be hardly detected in the thermogram.…”

“…In order to obtain polymer-based composites suitable for the development of magnetocaloric devices, high filler loadings are desirable to partially offset the inherent low thermal conductivity of the polymers. Polycaprolactone (PCL) showing low melting point and high ductility close to ambient temperature appears as a good candidate for the development of high filling-factor composites for MCE applications [29][30][31]. On this basis, in the present work a Ni-Mn-In-Co/PCL magnetic composite with a high proportion of active microparticles (MPs), able to feed standard and cheap FDM 3D printers, has been elaborated and characterized.…”

Taguchi design and optimization of the PLA/PCL composite filament with plasticizer and compatibilizer additives for optimal 3D printing

“…This indicates that the heterogeneous nucleation effect enhances the crystallization ability of the PLA/PCL composite. 62,63 In the heating curve (B), the PLA curve exhibits a double melting peak, where the lower melting peak is attributed to the incomplete melting of the α 0 crystals due to a slow heating rate. 41 The melting temperatures (T m ) of PCL and PLA in the PLA/PCL composite do not show significant variations compared to their respective pure components, indicating that the fatty chains of PCL exhibit better thermal stability in the presence of other polymers and particles.…”

Three-Dimensional Printing of Lignocellulose Structures: Improving Mechanical Properties and Shape Fidelity

“…Three-dimensional (3D) printing, or additive manufacturing (AM) technology, creates physical objects from 3D models, usually layer-upon-layer patterns . This technology can quickly fabricate micro-to-macro-scale freestanding 3D structures without mold using single or multiple materials. , Depending on the materials, various AM techniques can be selected for fabricating 3D structures, including fused deposition molding (FDM), extrusion printing (EP), inkjet bioprinting, and powder fusion printing. − FDM and EP are the most attractive for printing thermoplastic, thermoset, and biopolymer composites among different AM techniques. In FDM, thermoplastic filaments of polycarbonates, polylactic acid, and acrylonitrile butadiene styrene melt at the nozzle into a semiliquid state and are extruded in a layerwise pattern to fabricate 3D structures. , In contrast, EP techniques can print precisely various materials, including thermosets and highly viscous wood-derived polymers such as nanocellulose under ambient conditions in a layerwise pattern …”