The development of polyaniline and graphene oxide composites aims to join the unique properties of each material for aerospace applications. The present paper demonstrates an easy and quick method, compared to the ones found in the literature, to obtain a composite made with polyaniline doped with dodecylbenzenesulfonic acid, a combination commonly called polyaniline, and graphene oxide. Nowadays, the most common studied methods are electrochemistry and in situ chemical polymerization. Differently from these methods, the films were obtained by a physical mixture of equimolar suspension of graphene oxide (4 mg/mL) with 3 concentrations of polyaniline powder: 25; 50 and 75%, being compared to pure graphene oxide and polyaniline. The morphology and structure behavior of all the films were studied, besides the bonding nature between both materials. The films were analyzed by scanning electron microscopy, X-ray diffraction, Fourier transform infrared spectroscopy, and differential scanning calorimetry. The apparent interaction between graphene oxide corrugated sheets and polyaniline grains was verified by scanning electron microscopy images. It can be noticed, as the concentration of polyaniline increases, that more polymer was entrapped. To prove the formation of polyaniline/graphene oxide composite, X-ray diffraction and Fourier transform infrared spectroscopy techniques demonstrated the changes on graphene oxide crystallographic plans and on the chemical bonding between polyaniline and graphene oxide, suggesting an interaction between polyaniline and graphene oxide, especially in the composite with 50% polyaniline/50% graphene oxide. Differential scanning calorimetry was used to highlight this effect through the increase in thermal stability. The method of physical mixture was efficient to obtain the polyaniline/ graphene oxide composites.

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The carbon materials and conducting polymers are known by application in electronic devices. This work aims to study the initial steps parameters of polyaniline electrosynthesis on carbon felts annealed at 1600 K by changing the number of voltammetry cycles in aniline acid solution. The characterization was performed by Field Emission Gun – Scanning Electron Microscopy, X-ray Diffraction, Infrared Fourier Transform Spectroscopy, Raman Spectroscopy and Electrochemical Impedance Spectroscopy. Under increasing number of cycles, the growth was more intense and it was easy to observe the pores clogging. Besides, it was noticed that emeraldine formation occurred progressively, from structures less to more oxidized: the polyaniline less cycled resulted closest that leucoemeraldine; polyaniline from nine cycles resulted closest to emeraldine, but all of them showed electroactive defects related to electrical charge (polarons) and conductivity (bipolarons). It was also observed that prime layers of polyaniline, formed until three cycles, followed more intense attraction of charges in solution to layer surface. This effect was emphasized from 3rd to 6th cycles.