Unraveling the polishing processes and mechanisms of polyacrylate silyl ester based antifouling coating: A molecular dynamic study

Self-polishing coatings (SPCs) can renew its surface and consequently prevent the adhesion of marine fouling. In order to unravel the molecular mechanism, in this work, molecular dynamics (MD) simulations were conducted to simulate the polishing process of typical triisopropyl silyl acrylate (TIPSA). The results show that the poor static antifouling performance of TIPSA is due to the spontaneous adsorption of hydrolyzed side groups (silyl groups) onto the coating surface undertheir strong Van der Waals (vdW) nonbonding interactions. The infiltration of water molecules at the interface between hydrolyzed silyl groups and coating surface promotes the polishing process. However, when the number of permeated water molecules is not enough to screen the nonbonding interactions, the hydrolyzed silyl groups can be adsorbed on the resin matrix again. The formation of water channel in the hydrolyzed silyl layer further restrains the polishing process. In addition, the uneven distribution of hydrophilic groups in resin matrix surface also plays an important role in the polishing process of the TIPSA coating. This work deepens our understanding of the polishing process and mechanism of SPCs and might be able to open a new direction to further comprehend the antifouling mechanism.