Inductive Thermal Effect on Thermoplastic Nanocomposites with Magnetic Nanoparticles for Induced-Healing, Bonding and Debonding On-Demand Applications

Abstract

In this study, the heating capacity of nanocomposite materials enhanced with magnetic nanoparticles was investigated through induction heating. Thermoplastic (TP) matrices of polypropylene (PP), thermoplastic polyurethane (TPU), polyamide (PA12), and polyetherketoneketone (PEKK) were compounded with 2.5–10 wt.% iron oxide-based magnetic nanoparticles (MNPs) using a twin-screw extrusion system. Disk-shape specimens were prepared by 3D printing and injection molding. The heating capacity was examined as a function of exposure time, frequency, and power using a radio frequency (RF) generator with a solenoid inductor coil. All nanocomposite materials presented a temperature increase proportional to the MNPs’ concentration as a function of the exposure time in the magnetic field. The nanocomposites with a higher concentration of MNPs presented a rapid increase in temperature, resulting in polymer matrix melting in most of the trials. The operational parameters of the RF generator, such as the input power and the frequency, significantly affect the heating capacity of the specimens, higher input power, and higher frequencies and promote the rapid increase in temperature for all assessed nanocomposites, enabling induced-healing and bonding/debonding on-demand applications.

The Influence of Thermoplastic Composite Recycling on the Additive Manufacturing Process and In-Use Phase as Candidate Materials for Wearable Devices Applications

“…The PA thermoplastic matrix was chosen due to its strong adhesion with textiles for the production of 3D-printed wearable devices [ 23 ] with pertinent specifications while providing the required stiffness at the same time. Additionally, MNPs were added into the thermoplastic matrix to offer either self-healing properties that can repair minor damages, like scratches or cracks [ 24 ], or heating induction [ 25 ] in order to advance the durability of the final ski boot. Moreover, iron MNPs have also been investigated as additives for 3D-printed magnets and soft-robotics applications [ 26 ].…”

Leaching of Nano-Additives as a Method for Life-Cycle Suitability: A Study on 3D-Printed Nanocomposites for Wearables Applications

“…CCFs were introduced [8][9][10] in matrices since they enhance the mechanical properties of the final 3D-printed parts. Furthermore, in order to increase the durability and reliability of the final 3D-printed wearable devices, SPIONs were incorporated within the thermoplastic matrix offering self-healing properties repairing minimal damages such as scratches or cracks when external magnetic field [12] ore even heating induction is applied [13].…”

“…Furthermore, other nanomaterials such as superparamagnetic iron oxide nanoparticles (SPIONs) have been developed as novel drug delivery vehicles and have found application in magnetic resonance imaging (MRI) and magnetic hyperthermia [11]. Upon activation of an external magnetic field [12] or even heating induction [13], SPIONs can promote self-healing to wearable devices via magnetic attraction. Exposure to SPIONs could potentially lead to toxic side effects such as membrane leakage of lactate dehydrogenase, impaired mitochondrial function, and DNA damage [14].…”

Integrating Exposure Assessment and Process Hazard Analysis: The Nano-Enabled 3D Printing Filament Extrusion Case

“…Local melting enabled polymer chains' interdiffusion, which allowed facile bonding/debonding. Several polymer matrices reinforced with Fe 3 O 4 nanoparticles, including TPU and PA12 under study in the present work, have been investigated for their induced heating and healing ability [33]. All thermoplastic nanocomposites with MNP concentrations from 2.5-10 wt%, resulted in induced heating after a short period of exposure to the alternating magnetic field.…”