Polymer-graphene composites by the photocuring of a system containing benzophenone macromer

Abstract

Formulations incorporating benzophenone-oligodimethacrylate (BP-DMA) and graphene structures, i.e., graphene oxide (GO) and reduced graphene oxide (RGO), were exposed to UV-Vis irradiation or a femtosecond laser beam to achieve hybrid composites. All structures were characterized through various methods, including 1H-NMR and FTIR spectroscopies, optical microscopy, TEM, ESEM/EDAX analysis and DSC/XRD techniques. The photopolymerization of BP-DMA in the monomer compositions with and without GO or RGO was investigated by photo-DSC and FTIR methods to determine the kinetic parameters of the polymerization. The photopolymerization experiments revealed a good photoreactivity of the monomers (degree of conversion: 65-77 %) after 1 min exposure to UV-Vis irradiation and the addition of graphene (up to 0.5 %), whereas the polymerization rate varied between 0.14 and 0.1 s-1. Moreover, two-photon photopolymerization of the formulations in the presence/absence of GO or RGO nanosheets (0.1 wt. %) generated 2D microstructures by the direct laser writing procedure. Furthermore, the morphology and the properties of composites materials were analyzed.