The present study proposes an alternative eco-friendly method to prepare a thin composite coating based on graphene embedded in siloxane polymers which can be used as application for the corrosion protection of steel. The nanocomposite coatings were elaborated by a dielectric barrier discharge using a nebulized colloidal suspension of graphene nanosheets (GNs) dispersed in hexamethyldisiloxane (HMDSO) used as the precursor for the polymer matrix. After obtaining a stable colloidal solution, it was nebulized into the plasma reactor to form a plasma polymer (pp) coating from HMDSO (ppHMDSO) in which GNs were incorporated (GN@ppHMDSO) on the mild steel substrate. The chemical structure of the hybrid coatings was characterized by X-ray photoelectron spectroscopy and Fourier transform infrared spectrometry. Raman spectra of GNs and GN@ppHMDSO coatings suggest the existence of charge transfer between the GNs and the HMDSO matrix. Furthermore, scanning electron microscopy confirms the synthesis of micro/nanocomposite with a fairly homogeneous dispersion of the GNs in the polymer matrix. The corrosion resistance of the samples was evaluated by electrochemical impedance spectroscopy which showed that the hybrid coatings GN@ppHMDSO deposited by a one-step atmospheric pressure plasma process, presented excellent anticorrosion performance with 99.99% of protection efficiency.

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In this work, the surface modification of ultra‐high‐molecular‐weight polyethylene (UHMWPE), a linear polymer, by a helium transporting discharge at atmospheric pressure was investigated by means of FTIR, AFM, XPS, ToF‐SIMS, and contact angle measurements. Two types of discharge configurations, that is, jet and glow of the transporting discharge for the surface treatment of polymer substrates were studied. The results show that the position of the UHMWPE polymer substrates plays an important role in the surface modification and stability of the treatment. The polymer substrates placed inside the transporting discharge tube present more stable wettability and surface modification. In addition, the transporting discharge was used to modify the inner surface of the high density polyethylene tube.