Preparation and Performance of a Photocurable Degradable Waterborne Boron-Containing Polyurethane Acrylate Anti-Fouling Coating

Biofouling has a detrimental effect on marine infrastructure and poses a severe challenge to the global marine industry. Therefore, developing efficient and environmentally friendly anti-fouling coatings to protect those facilities has become extremely necessary nowadays. To address marine biofouling, a series of photocurable degradable waterborne boron-containing polyurethane acrylate (WPU-PTPBx) anti-fouling coatings were prepared by grafting pyridine-triphenylborane (PTPB) onto polyurethane side chains and UV curing. FTIR and 1H NMR confirmed the successful grafting of PTPB. The WPU-PTPBx aqueous dispersions had a particle size of 30~75 nm with excellent thermal storage stability. DSC and XRD characterizations revealed the amorphous structure of the coatings, which favored biodegradation. All coatings exhibited adhesion strength over 2 MPa, meeting marine application requirements. Antibacterial and anti-algal tests showed that PTPB content positively correlated with anti-fouling performance: the coating achieved a 99.66% inhibition rate against Escherichia coli and reduced the adhesion density of Nitzschia closterium to only 36.9 cells/mm2. With favorable degradability and outstanding anti-fouling performance, WPU-PTPBx coatings are promising green anti-fouling materials for marine applications.