Estudo da grafitização de espuma leve de carbono obtida através da pirólise de Polietileno Tereftalato (PET)

Abstract

Due to its versatility and excellent cost-effectiveness, plastic materials are widely used for numerous applications and, currently, most of them are improperly discarded after consumption. This residue ends up accumulating in the soil and oceans, where it remains for many years, suffering slow degradation and causing various environmental problems. The problem is growing and the prospects for growth in plastic consumption and disposal are worrying. Seeking to remove this environmental liability from the environment, a graphene production technique was developed and patented from polyethylene terephthalate (PET), one of the most used plastics today. This transformation technology brings economic and social benefits, as it produces a material that is increasingly used, graphene, with a wide range of applications in engineering and industry, high added value, low cost, and, above all, that contributes to sustainability. In this work, starting from the mentioned patent, the pyrolysis of PET assisted by chemical compounds was tested with the objective of acting as expansion agents of the carbon precursor during this process. Furthermore, the effect of heat treatment on the post-pyrolysis material was studied, in order to evaluate possible improvements in its crystalline structure, and aspects related to electrical conductivity, aiming at its application in energy storage devices. The materials produced with the aid of expanding agents were compared with those produced without agents. After the characterizations, it was observed that the best results were obtained using melamine and urea as expanding agents, since they presented results more similar to graphene, among those studied. Regarding heat treatment, significant improvements in electrical conductivity were observed. Some of the materials were tested as supercapacitors and, despite the low capacitance results, they showed potential for application, provided that some improvements are made that need to be studied. In view of this, the material produced has the potential to be a solution to the problem caused by plastic as an environmental liability, since it can be applied, if properly improved, in higher value-added applications, bringing economic bias to the material.