UV-Initiated Frontal Polymerization for the Fast Synthesis of Bubble-Free, Self-Propagating Hydrogel Anticorrosive Coatings

Hydrogels are formed through the cross-linking of hydrophilicpolymerchains within an aqueous microenvironment. A novel synthesis strategy,UV-initiated frontal polymerization to quickly synthesize bubble-free,self-propagating hydrogel anticorrosive coatings in aqueous conditions,was presented, in which the self-propagating polymerization rate reached16.7 mm min(-1). SEM, AFM, FTIR, EIS, IC, XPS, andultra-depth-of-field microscopy were used to characterize the surfacemorphology and anti-corrosion properties of the hydrogel coating.The addition of nano-SiO2 formed dense hydrogen bonds,and the stability of the three-dimensional network was enhanced. Underwater,the hydrogel coating could physically block corrosive media from reachingsteel surfaces, and it was 75% effective at blocking chloride ionsafter 7 days under osmotic pressure. In addition, 1,2,4-triazole accumulatedon the steel surface, and then the active anti-corrosion functiontook effect. This paper provides the basis for the in situ synthesisof hydrogel anticorrosive coatings on the surface of mild steel ina wet or underwater state.