Synthesis of Silica/Polypyrrole Nanocomposites and Application in Corrosion Protection of Carbon Steel

Abstract

Silica/polypyrrole nanocomposites without dopant (SiO2/PPy) and with oxalate dopant (SiO2/PPyOx) were synthesized using polymerization of pyrrole in the presence of nano SiO2. Synthesized SiO2/PPy and SiO2/PPyOx were characterized by FTIR, SEM, TEM and EDX and their electrical conductivities were determined by CV method through the two-point-electrode without electrolyte. The corrosion protection performance of polyvinylbutyral (PVB) coatings containing SiO2/PPyOx was evaluated and compared with that of pure PVB coatings and of PVB coatings containing SiO2/PPy by electrochemical impedance spectroscopy and adhesion measurement. The results show that electrical conductivities of SiO2/PPy and SiO2/PPyOx were 0.181 and 0.109 S/cm, respectively. The ratio of PPy on SiO2 in SiO2/PPy and SiO2/PPyOx composites was 0.77/1 and the ratio of oxalate on PPy in SiO2/PPyOx composite was 1.24/1. SiO2/PPy and SiO2/PPyOx improved corrosion resistance and adhesion of PVB coatings. The presence of oxalate in SiO2/PPyOx significantly enhanced the effect of SiO2/PPy on the protection performance of PVB coatings.

Evolução Do Curso De Engenharia De Minas Na Uemg/João Monlevade Em Seus 10 Anos De Existência

“…O polipirrol é um polímero condutor que tem sido investigado para inumeras aplicações, destacando-se sensores, baterias, membranas e dispositivos semicondutores. Apresentam algumas vantagens em relação aos semicondutores tradicionais, como a flexibilidade e a facilidade de processamento ( VAN et al, 2018).…”

Evaluation of the Corrosion Inhibiting Capacity of Silica/Polypyrrole-Oxalate Nanocomposite in Epoxy Coatings

“…Among ICPs, polypyrrole (PPy) is widely used due to its unique properties such as environmental stability, high conductivity, and anticorrosion ability [12][13][14][15]. The researches in PPy's applications are focusing on the use of PPy film for a protective coating or anticorrosion additives organic coatings [13,[16][17][18][19][20]. Nanosilica particles are incorporated inside the matrix of conducting polymer in order to form a core-shell structure of ICPs-Silica, which results in the increase of the active area surface of the conducting polymer, compared to its bulk form.…”

“…On the whole, there are clear evidences that PPy provides corrosion protection for steel [13][14][15][16][17][18][19][20]. Besides this, several operating corrosion protection mechanisms have been proposed, such as barrier protection, corrosion inhibition, and anodic protection.…”

“…Besides this, several operating corrosion protection mechanisms have been proposed, such as barrier protection, corrosion inhibition, and anodic protection. It has been suggested that anodic protection, a shift in corrosion potential from the active region to passive one, can explain the protective capacity of PPy toward steel [18][19][20]. But the maintenance of PPy protective ability alone is limited.…”

The Role of Counter Anions in Anticorrosive Properties of Silica-Polypyrrole Composite

“…All in all, it is believed that PPy provides corrosion protection for steel [12][13], however to completely understand about the mechanism is still challenging because of different possible oxidation states and experimental parameters. It has been suggested that PPy can reduce the rate corrosion by forming a protective barrier layer and anodic protection, occurring a shift in corrosion potential to more positive values [14].…”