Utilization of reactive polymer for development of versatile antifouling coatings

Abstract

Antifouling polymer coatings have important implications for many industrial applications. The initial demand comes from marine vessels where bio-foulant buildup can reduce the life span and fuel efficiency of the ships. The second area of increasing demand is coatings for biomedical implants and biosensors, where surface treatments are necessary to counter contamination by proteins and cells. The most widely employed polymers as antifouling materials are polyethylene glycol (PEG) for its fouling-resistant property and polydimethylsiloxane (PDMS) for its fouling-release property. Recent reports suggest that copolymers containing both PEG and PDMS may show synergistic effects, and the performance depends on the copolymer composition. However, as the synthesis of copolymers with variable composition can be difficult and time-consuming, studies on the effect of copolymer composition on antifouling performance remain limited. In this study, we report the preparation of copolymers containing PEG and PDMS side-chains by utilizing poly(pentafluorophenyl acrylate) (PPFPA) as a reactive precursor polymer. The PPFPA polymer is first synthesized via reversible addition-fragmentation chain transfer (RAFT) polymerization. By utilizing the reactive PFP ester groups, amine-functionalized PEG and PDMS chains are then grafted onto the PPFPA backbone to yield copolymers of varied sidechain compositions. The resulting copolymers are spin-coated onto silicon wafer surfaces then tested against cells, proteins, and marine organisms. In all scenarios tested, the copolymers are found to show better antifouling performance than PEG or PDMS homopolymer. Moreover, optimized copolymer composition is determined depending on the nature of the fouling organism. Collectively, our study presents a versatile synthesis method to prepare copolymers of optimized composition to suit different antifouling application needs.