Oligo(2-alkyl-2-oxazoline)-based graft copolymers for marine antifouling coatings.

[Display omitted] • The combination of CROP and RAFT polymerization was applied to synthesize graft copolymers presenting oligosiloxane and oligoalkyloxazoline side chains with fully tunable composition. • Poly(oxazoline)-based graft copolymers were applied to fabricate PDMS-based antifouling coatings. • Graft copolymers featuring oligoalkyloxazoline side chains emerged as valid alternatives to PEG-based derivatives as surface-active additives to fabricate antibiofouling coatings. • Graft copolymers including oligoalkyloxazoline grafts proved more efficient than their PEG-containing counterparts in inhibiting the settlement and promoting the removal of marine macrofoulers. Poly(ethylene glycol) (PEG)-based graft copolymers have been widely applied for the modification of poly(dimethyl siloxane) (PDMS)-based coatings that resist marine biofouling. In this research, we synthesized oligo(2-alkyl-2-oxazoline) (OAOXA)-based graft copolymer analogues, and subsequently tested their applicability in the formulation of structurally similar coatings, aiming to highlight the influence of polymer composition on biopassive properties. In particular, poly(dimethyl siloxane methacrylate)- co -oligo(2-alkyl-2-oxazoline)methacrylate copolymers were synthesized by reversible addition fragmentation chain transfer (RAFT) polymerization, starting from oligo(2-ethyl-2-oxazoline)- and oligo(2-methyl-2-oxazoline)-methacrylate macromonomers (OEOXMA and OMOXMA, respectively). Amphiphilic copolymer films with OAOXA grafts were found to be more hydrophilic with respect to those obtained using PEG analogues. PDMS coatings containing the graft copolymers as surface additives were tested towards the settlement of the macrofouler Ficopomatus enigmaticus and the diatom Navicula salinicola. The biofouling experiments indicated that OAOXA-containing films showed a comparable and in some cases improved performance with respect to their PEG-based counterparts, thus highlighting how OAOXA-based graft copolymers represent a valid alternative to PEG derivatives as surface-active additives to design antibiofouling coatings. [ABSTRACT FROM AUTHOR]