Polymeric nanocomposites from polycaprolactone and carbon nanotubes: electrospinning parameters optimization

Abstract

In the last decades, electrospinning via polymeric solutions has been widely used to produce ultrathin and nano-scaled fibers, which have found many applications in the tissue engineering field. In this context, carbon nanotubes (CNT) have been considered an excellent choice as reinforcing agents due to its impressive properties, such as mechanical, electrical and physical-chemical. This project has as the main goal the optimization of the electrospinning parameters of polycaprolactone/multi-walled carbon nanotubes (PCL/MWCNT) solutions. Furthermore, all nanocomposites will be characterized in order to evaluate the dependence of their final properties with the MWCNT content. MWCNT will be produced at the Associated Sensors and Materials Laboratory (LAS), located at the National Space Research Institute (INPE). For this, we will use a chemical deposition system via thermal vapor deposition (CVD), followed by purification in acid bath. Next, the MWCNT will be functionalized by a chemical route (nitric and sulfuric acids) aiming at attaching oxygen-containing groups at their surface, therefore generating a final material with enhanced polarity. In sequence, the nanocomposites will be produced by electrospinning from solutions containing PCL (at 12 wt%), a biocompatible and biodegradable polymer, and varied acid-functionalized MWCNT contents (0-3 wt%). All electrospun materials will be further characterized by morphological and structural techniques, such as Scanning Electronic Microscopy (SEM), Transmission Electronic Microscopy (TEM), Raman Spectroscopy, Attenuated Total Reflectance Infrared Fourier Transform Infrared Spectroscopy (ATR-FTIR), Differential Scanning Calorimetry (DSC) and X Ray Diffraction (XRD). At the end of this project, we expect to achieve optimal electrospinning conditions, which in turn will allow us to produce defect-free electrospun materials at a wide range of MWCNT content. Moreover, the physical and chemical properties of all materials will be carefully evaluated, aiming at future applications in the biomedical and tissue engineering fields. (AU)