Waterborne acrylic–polyaniline nanocomposite as antistatic coating: preparation and characterization

Eco-Friendly AMPS-Doped Polyaniline/Urethane-Methacrylate Coating as a Corrosion Protection Coating: Electrochemical, Surface, Theoretical, and Thermodynamic Studies

In this study, 2-acrylamido-2-methylpropanesulfonic acid (AMPS)-doped polyaniline (PANI) fibers were used as polymerizable smart anticorrosive agents to prepare eco-friendly UV-curable anticorrosive coatings. For this purpose, AMPS-doped PANI fibers were synthesized through chemical oxidative interfacial polymerization. The size and chemical structure of the prepared conducting fibers were characterized by scanning electron microscopy, ¹H NMR, and Fourier transform infrared (FTIR) analyses. As a binder for the prepared conducting fibers, an eco-friendly fluorinated urethane-methacrylate dispersion was synthesized and fully characterized using FTIR analysis. Subsequently, various amounts of the synthesized fibers were mixed with the fluorinated binder to prepare UV-curable anticorrosive coatings. The physicochemical interactions between the PANI fibers and UV-curable binder were studied thoroughly using differential scanning calorimetry and thermogravimetric analyses and measurement of the gel contents and adhesion strength of the prepared composite coatings. The corrosion resistance performance of the prepared coatings was evaluated using electrochemical impedance spectroscopy analysis, and the obtained results revealed that the presence of 2 wt % of the AMPS-doped PANI fibers significantly enhanced the corrosion resistance of the obtained coating. In addition, the corrosion layers of the coatings were analyzed using X-ray photoelectron spectroscopy, which indicated that the AMPS-doped PANI fibers changed the composition of the corrosion product layer. To expand these attempts, this study also explores the interaction of AMPS-doped PANI fibers with the Fe(100) surface using density functional theory as well as atom in molecule calculations. All of the obtained results proved that the outstanding corrosion protection performance of the prepared composite coatings originated from exceptional chemical interactions between the unsaturated doping agents of the prepared PANI fibers and the UV-cured polymer.

A short review on polyaniline (PANI) based nanocomposites for various applications: enhancing the electrical conductivity

This short review has summarized the significance of polyaniline (PANI) advanced polymer that focusing into their modification strategy, electrical conductivity and various potential applications. PANI is one type of conductive polymer that was synthesized by oxidative aniline polymerization with varied concentration of acid dopant. In recent year, many researches has been conducted specifically to enhance the electrical conductivity of PANI. There have been numbers of studies involving PANI that specially reported the electrical conductivity could be improved through proper dopant (acid) selection and robust composite strategy. The PANI based nanocomposite shows higher electrical conductivity by integrating it with nanofiller due to the filler-matrix interface contact. Therefore, by modifying the PANI properties, it could be benefited for various potential application in the future.

Preparation and Characterization of Low Infrared Emissive Aluminum/Waterborne Acrylic Coatings

An aluminum/waterborne acrylic coating was developed by orthogonal experiments, and the gloss, emissivity, chromatic distortion, hardness, adhesion, impact resistance, and corrosion resistance of the coatings were examined. The results showed that the effect of drying time on the infrared emissivity of coatings was more significant than that of the Al powder concentration and nano-silica slurry. When the drying time was prolonged from 0.5 to 6.0 min, the gloss of the coating decreased slowly and the gloss remained low. The infrared emissivity first decreased and then increased. The infrared emissivity of coatings dried for 2.0 min was better. The L’ value gradually decreased and showed a small change of range. With the increasing of the drying time, the hardness of the coating gradually decreased and was the highest at 0.5–2.0 min. The drying time had no effect on the adhesion level. The impact resistance of the coating was better during the drying period of 1.0–3.0 min. The corrosion resistance of the coating was better at 2.0 min. When the drying time was 2.0 min, the waterborne coating showed the better comprehensive performance. This study provides new prospects in using low infrared emissive coatings for infrared stealth and compatibility with visible light.

Formation and behavior of negative ions in low pressure aniline-containing RF plasmas

This paper is focused on the formation mechanisms and the general behavior of negative ions in low pressure radio-frequency (RF) plasmas operated in a mixture of argon and aniline vapor. This type of plasma is mostly used for the synthesis of polyaniline, one of the most studied conductive polymers. Experiments based on mass spectroscopy measurements reveal the necessity to have a thin layer of plasma synthesized polyaniline on the electrodes to produce negative ions through complex surface reactions. In addition, thin-films deposited using this type of discharge are analyzed by means of Near Edge X-ray Absorption Fine Structure spectroscopy (NEXAFS). The material analysis gives a first indication about the possible contribution of negative ions to polyaniline deposition.