Molecular Assembly between Weak Crosslinking Cyclodextrin Polymer and trans-Cinnamaldehyde for Corrosion Inhibition towards Mild Steel in 3.5% NaCl Solution: Experimental and Theoretical Studies

Abstract

Constructing molecular assembly between a soluble cyclodextrin polymer (SCDP) and an anticorrosive component is conducive to increasing the availability of a corrosion inhibitor with low molecular polarity in aqueous solution. The SCDP was prepared via the weak crosslinking effect of glutaraldehyde using β-cyclodextrin as the subunit, whose structure was confirmed by proton nuclear magnetic resonance spectra (1H NMR), X-ray diffraction and morphology. An assembly between SCDP (host) and trans-cinnamaldehyde (guest, CA) was constructed, and the intermolecular interactions were disclosed by Fourier transform infrared spectra (FTIR). The corrosion inhibition of SCDP/CA assembly for mild steel in 3.5% NaCl solution was assessed through electrochemical and surface analyses. 1H NMR results showed that exterior hydroxyls of β-cyclodextrin were the active sites for crosslinking. Hydrogen bonds might be the binding force between SCDP and CA according to FTIR analyses. Electrochemical measurements revealed that SCDP/CA assembly could suppress both cathodic and anodic reactions and enhance the polarization impedance for mild steel in the corrosive medium with a maximum efficiency of 92.2% at 30 °C. Surface analyses showed that CA molecules could be released from the assembly followed by the energy competition mechanism, and solely adsorb on the steel surface in parallel form, which was further evidenced by theoretical modeling.

Síntesis De Una Base De Schiff A Partir De Dopamina Y Cinamaldehído

“…El espectro IR del CA, Figura 1, se registró una banda intensa a 1665 cm −1 , característica de la frecuencia de tensión simétrica del grupo carbonilo, υ s C = O, y una banda fina de intensidad media a 1449 cm −1 , asignada a la tensión υ C−H en el plano, del grupo aldehído [42,43]. El espectro IR de BS-DA-CA, registró una señal de baja intensidad a 1603.76 cm −1 , que se asignó a la vibración de tensión υ C=N ; la señal de baja intensidad a 1449 cm −1 propia de la vibración de torsión υ C−H del aldehído, presentó un desplazamiento a 1437 cm −1 en la imina sintetizada.…”

Preparation and Anti-Corrosive Properties of Waterborne Epoxy Composite Coating Containing Graphene Oxide Grafted with Sodium Tripolyphosphate

“…EIS is an effective technique to evaluate and predict the barrier and corrosion resistance of organic coatings [33,34]. Figure 6 shows the Nyquist and Bode plots of coatings at different immersion times in 3.5 wt.% NaCl solution.…”

Synthesis, Anti-microbial, Flameretardance and Anti-corrosive Activity of Some New Heterocycles Incorporating Coumarin moiety

“…A mixture of (3) (0.01 mol) and benzoylchloride (0.01 mol) in (20ml) dry benzene was heated under reflux for 6 hrs., The solid was collected after concentration, washed with diethylether, dried and purified by recrystallization from ethanol to give (14).…”

“…Similarly, compound (3) was reacted with benzoyl chloride in boiling dry benzene to afford the corresponding N-(4-(2-chlorophenyl)-3cyano-6-(7-hydroxy-2-oxo-2H-chromen-3-yl) pyridin-2-yl)benzamide (14). IR spectrum showed absorption bands at 3431 , 1700,1624 cm -1 , attributed to NH , , CO-amide.…”

“…Corrosion can lead to failure of metal structures which have serious consequences for humans and the environment. Thus, the study of mild steel corrosion and the inhibition of mild steel corrosion of have invited the attention of scientists and technocrats to devise ways to control the corrosion [14][15][16].…”