Amino Acid Interleaved Layered Double Hydroxides as Promising Hybrid Materials for AA2024 Corrosion Inhibition. Issue 13 (19th January 2016)

• Record Type: Journal Article
• Authors: Stimpfling, Thomas; Vialat, Pierre; Hintze‐Bruening, Horst; Keil, Patrick; Shkirskiy, Viacheslav; Volovitch, Polina; Ogle, Kevin; Leroux, Fabrice
• Other Names: Garcia Yann sponsoringEditor.; Su Bao‐Lian sponsoringEditor.
• Is Part Of: European journal of inorganic chemistry. Issue 13/14(2016)
• Page Start: 2006
• Page End: 2016
• Publication Date: 2016-01-19
• Subjects: Organic–inorganic hybrid composites -- Layered compounds -- Corrosion inhibitors -- Inorganic reservoirs -- Amino acids -- Polymer coatings; Chemistry, Inorganic -- Periodicals; Organometallic chemistry -- Periodicals; Bioinorganic chemistry -- Periodicals; Solid state chemistry -- Periodicals; 546
• DOI: 10.1002/ejic.201501161
• Languages: English
• ISSNs: 1434-1948

Abstract

Abstract: Various α‐amino acid (αAA) molecules were screened for their ability to retard the corrosion of AA2024 aluminum alloy substrate. The αAAs screened wereL ‐arginine (L ‐Arg), L ‐asparagine (L ‐Asn), L ‐cysteine (L ‐Cys), L ‐cystine, L ‐histidine (L ‐His), L ‐methionine (L ‐Met), L ‐phenylalanine (L ‐Phe), L ‐serine (L ‐ser), L ‐tryptophan (L ‐Trp), andL ‐tyrosine (L ‐Tyr). From their performances compared with that of the reference additives chromate and 2‐mercaptobenzothiazolate (MBT), L ‐Cys andL ‐Phe were selected, and their layered double hydroxide (LDH) interleaved derivatives were further scrutinized. Different LDH phases, namely, LiAl2, Mg2 Al, MgZnAl, and Zn2 Al, were tested as hosts for the inhibitor αAA substances, and the materials were characterized by XRD, FTIR spectroscopy, and SEM. The efficiencies and durable performances of the hybrid materials as an anticorrosion agents for aluminum alloy 2024 (AA2024) were demonstrated through direct current (DC) polarization measurements, and the evolution of the polarization resistance was recorded. The mechanism of inhibition focused on the most promising hybrid material LDH/L ‐Cys and was tentatively explained as anion exchange and dissolution of the inorganic framework at the cathodic and anodic corrosion zones, respectively, with the particular occurrence of Cu‐rich intermetallic zones. The obtained results evidence that the LDH/L ‐CYS assembly embedded in the polymer coating retards the corrosion process of the AA2024 substrate after a prolonged immersion time. Abstract : An assembly composed ofL ‐cysteine (L ‐Cys) intercalated into a layered double hydroxide (LDH) is used as an ion‐exchange inorganic functionalized filler dispersed in an epoxy‐based primer layer. Upon corrosion, L ‐Cys molecules are released from the LDH container either by anion exchange or platelet dissolution and retard the corrosion of aluminum alloy AA2024 efficiently.