Magnetically active nanocomposites based on biodegradable polylactide, polycaprolactone, polybutylene succinate and polybutylene adipate terephthalate

Abstract

The development of multifunctional materials and their application in flexible electronics has shown a remarkable relevance in areas such as artificial e-skin, flexible touch sensors, health monitors or implantable devices, among others. However, conventional systems rely on polymers that are not biodegradable, generating undesired and uncontrolled waste streams directly ending into oceans or landfills. Bearing this in mind, this work reports on degradable magnetic nanocomposites based on a series of biodegradable polyesters, a prominent group of polymers recognized by their biodegradability. Thus, poly(L-lactide) (PLLA), polycaprolactone (PCL), polybutylene succinate (PBSu), and polybutylene adipate terephthalate (PBAT) have been blended with magnetic Fe3O4 nanoparticles up to 10 wt%. Differential scanning calorimetry reveals that after inclusion of the Fe3O4 nanoparticles, polymer crystallization can be boosted or restricted depending on the polymer matrix. Nanocomposite films with tuneable mechanical properties ranging from stiff and brittle to soft and ductile are obtained. A maximum Young's modulus of 2147 ± 174 MPa is obtained for the PLLA 1 wt% nanocomposite, while the PCL 10 wt% shows a relevant elongation at break of 833 ± 42%. Magnetization saturation linearly increases with Fe3O4 concentration, reaching a maximum magnetization value of 7.1 ± 0.1 emu·g−1 for the 10 wt% nanocomposite. The present work provides new paths for the fabrication of biodegradable magnetic materials and devices aimed to replace in the short and medium term durable conventional system based on petroleum-derived materials.