Ana Barros-Timmons
University of Aveiro, Portugal
Title: Grafting PLA onto Graphene Oxide and its Effect on Derived Nanocomposites
Biography
Biography: Ana Barros-Timmons
Abstract
Biodegradable and biocompatible polymers are have been attracting the attention of both academia and industry due to environmental concerns and to satisfy the requirements of demanding advanced applications especially in medicine. In this context, poly(L-lactide) (PLA) has been proposed for several applications as biodegradable thermoplastic. In turn, nanostructured graphene fillers with remarkable characteristics have also been used to enhance the mechanical, thermal, electrical and optical properties of many polymers. However, the full potential of the ensuing composites tends to be hindered by aggregation of the nanofillers. In order to promote a good dispersion of graphene oxide (GO) in the PLA matrix, polymer grafting techniques have been explored to anchor PLA onto graphene oxide surface which can act as compatibilisers. For that purpose PLA with a terminal triple bond was synthesized by ring-opening polymerization. By controlling the concentration of monomer to initiator, samples with three different chains lengths have been prepared and later coupled to azide-functionalized graphene oxide using the click chemistry. These hybrids mixed with commercial PLA and cast films have been preprared. The effect of chain length and of two loads of hybrid nanofillers on the properties of the ensuing nanocomposite films was studied using UV-visible spectroscopy, X-ray diffraction (XRD), differential scanning calorimetry (DSC), and nanoidentation and the results obtained will be discussed