• erodible coatings
• amphiphilic polymers
• polyethylene glycol
• microorganism
• self-polishing
• marine biofouling
• trialkylsilyl methacrylates
• hydrolyzable monomers

Amphiphilic hydrolyzable block copolymers composed of a polyethylene glycol (PEG) first block and a random poly(trialkylsilyl methacrylate (TRSiMA, R = butyl, isopropyl)-co methyl methacrylate (MMA)) second block were synthesized by RAFT polymerization. Two PEGs with different molecular weights (Mn = 750 g/mol (PEG1) and 2200 g/mol (PEG2)) were used as macroinitiators and the polymerization conditions were set in order to obtain copolymers with comparable mole content of trialkylsilyl methacrylate (30 mol%) and two different PEG mole percentages of 10 and 30 mol%. Block (PEG-b-MMA) and random (TRSiMA-co-MMA) copolymers were also synthesized as model polymers for comparison. The hydrolysis rates of PEG-b-(TRSiMA-co- MMA) in a THF/basic (pH = 10) water solution were shown by in situ 1H NMR to drastically depend on the nature of the trialkylsilyl groups and the mole content of PEG block. In particular, with TBSiMA based polymers underwent a much slower rate hydrolysis. Thermal analysis carried out by differential scanning calorimetry (DSC) revealed that PEG-b-(TRSiMA-co-MMA) copolymers were amorphous and characterized by two different glass transition temperatures (Tgs), one at  −45 mol%, typical of the PEG block, and the other above room temperature attributable to the TRSiMA-co-MMA second block, indicating the occurrence of a micro-phase separation in bulk of the copolymers. Copolymers were then used for the preparation of films by solution casting (100micron dry thickness) subjected to dynamic contact angle, surface erosion, topographical and morphological studies and biological assays against the diatom Navicula salinicola, taken as a model micro-organism. Measurements of advancing and receding contact angles with water confirmed the ability of the film surfaces to respond to the water environment, owing to a combination of hydrolysis of the silyl ester groups, especially TBSiMA, and a major exposure to water of the hydrophilic PEG units of the block copolymer. All the copolymer films tested were erodible in artificial seawater, with a wide range of erosion kinetics that could be modulated as a function of the copolymer design. Initial biological tests against N. salinicola indicate that the ability of PEG-b-(TRSiMA-co- MMA) copolymers to completely inhibit the settlement of diatoms is associated with a combination of two different mechanisms, namely the erosion of the film surface and its amphiphilicity and responsive character due to the incorporation of the trialkylsilyl methacrylate moieties and the hydrophilic PEG block, respectively.