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Title: Corrosion Protective Coatings from Poly(heterocyclic diphenylamine): Polyaniline Analogues
This study explores conducting polymers with side chains containing long, branched alkyl groups as candidates for corrosion suppression coatings. These polymers, containing carbazole, phenothiazine, and phenoxazine cores, may be considered as analogues to polyaniline, which is often employed in corrosion control applications. The polymers are prepared from the corresponding dibrominated carbazole, phenothiazine, and phenoxazine monomers with 2,5-dimethyl-1,4-phenylenediamine by the Buchwald−Hartwig coupling reaction. The effectiveness of these coatings for corrosion suppression was tested by potentiodynamic polarization studies and electrochemical impedance spectroscopy. The morphology of the coatings was characterized by scanning electron microscopy (SEM) and atomic force microscopy (AFM). Corrosion testing of coated AISI 4130 steels in 3.5 wt % NaCl showed that the phenothiazine- and carbazole-containing polymers display excellent corrosion resistance. The protection efficiency (PE) of 95.9% for phenothiazine outperformed the other polymers, including polyaniline coating. SEM images indicate that the polymers are still uniformly coated with stable morphology after 24 h of exposure to corrosive media. These results suggest that phenothiazine and carbazole-based PANI analogues may be candidates for protective organic coatings in transportation, aviation, marine, and oil and gas industrial applications.  more » « less
Award ID(s):
1945503
PAR ID:
10497662
Author(s) / Creator(s):
; ; ; ;
Publisher / Repository:
pubs.acs.org/acsapm
Date Published:
Journal Name:
ACS applied polymer materials
ISSN:
2637-6105
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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