Nanocompósitos poliméricos condutores e transparentes de poli (metacrilato de metila) e nanoestruturas de polianilina

Abstract

Polymer nanocomposites are materials which have two or more solid phases, matrix being a polymer and one of these phases should be in nano-sized scale range. When the resulting material is an electric conductor, this material is called conductive polymer nanocomposite. Polyaniline (PANI) is a conductive polymer that has considerably increased conductivity when found on the in nano-sized scale range. One method used to obtain PANI nanostructures is interfacial polymerization. Poly (Methyl Methacrylate) (PMMA) is an amorphous polymer, known for its high transparency in the visible spectrum and similarity with glass. The present work has the objective of obtaining a transparent and conductive polymer nanocomposite with potential for use in optical-electronic devices applications. For this, the synthesis of PANI nanostructures was first performed by interfacial polymerization. The films were obtained by the casting method in different volumetric fractions of PANI. The electron microscopy images performed in the PANI samples indicated that structures with different morphologies (nanofibers, nanolamines, nanoflores and plates) were obtained. The XRD showed that the obtained PANI nanostructures have high crystallinity and this crystallinity is morphologically dependent. As a function of the results, the synthesis that provided the growth of PANI nanofibers to obtain the composite was used. Considering the analyzes performed in the composites, it can be concluded that the 0.5% PANI film was shown to be more suitable for optical-electronic applications because it is the film that best combines transparency and conductivity. However, for applications in which the conductivity may be lower, films of 0.1 and 0.2% are shown as an excellent alternative, since they presented transmittance greater than 70%. Another advantage in the use of the films obtained in various applications is that they can also be presented as UVA and UVB filters in both protonated and deprotonated forms.