synthesis, characterization and hydrolysis behaviour of silyl acrylate terpolymers for use in self-polishing coatings

Self-polishing coatings (spcs) based on hydrolytically liable silyl (meth)acrylate polymers are among the most efficient marine antifouling coatings. in this study, terpolymers composed of triisopropylsilyl acrylate (sia), methyl methacrylate (mma) and n-butyl acrylate (ba) were synthesized as potential binders for use in spcs. free radical polymerization (frp) and the reversible addition-fragmentation transfer (raft) methods were employed for synthesis of the terpolymers at 45 wt% ratio of sia in feed. in the raft polymerization reactions, cyanoisopropyl dithiobenzoate (cdpd) was used as raft agent. all reactions were performed at 70°c in toluene and the terpolymers were characterized using ftir, 1h-nmr, gpc and dsc techniques. potential of the synthesized terpolymers for use in spcs was evaluated by measuring their accelerated hydrolysis rate in aqueous sodium hydroxide solution using inductively coupled plasma atomic emission spectroscopy (icp-aes). it was found that polymer molecular weight has a profound effect on its hydrolysis rate; such that terpolymers with mn of ~17,000 g/mol, synthesized via the raft method, hydrolyze extremely fast while those with mn of ~70,000 g/mol, synthesized via frp method, show a gradual slow progress in hydrolysis reaction. these results were attributed to the difference in mobility of the terpolymers, as estimated from reputation theory of de gennes. the results provide a promising route for tailoring polishing properties of silyl acrylate-based spcs.

Synthesis, characterization and hydrolysis behaviour of silyl acrylate terpolymers for use in self-polishing coatings

Self-Polishing Coatings (SPCs) based on hydrolytically liable silyl (meth)acrylate polymers are among the most efficient marine antifouling coatings. In this study, terpolymers composed of triisopropylsilyl acrylate (SiA), methyl methacrylate (MMA) and n-butyl acrylate (BA) were synthesized as potential binders for use in SPCs. Free radical polymerization (FRP) and the reversible addition-fragmentation transfer (RAFT) methods were employed for synthesis of the terpolymers at 45 wt% ratio of SiA in feed. In the RAFT polymerization reactions, cyanoisopropyl dithiobenzoate (CDPD) was used as RAFT agent. All reactions were performed at 70°C in toluene and the terpolymers were characterized using FTIR, 1H-NMR, GPC and DSC techniques. Potential of the synthesized terpolymers for use in SPCs was evaluated by measuring their accelerated hydrolysis rate in aqueous sodium hydroxide solution using Inductively Coupled Plasma Atomic Emission Spectroscopy (ICP-AES). It was found that polymer molecular weight has a profound effect on its hydrolysis rate; such that terpolymers with Mn of ~17,000 g/mol, synthesized via the RAFT method, hydrolyze extremely fast while those with Mn of ~70,000 g/mol, synthesized via FRP method, show a gradual slow progress in hydrolysis reaction. These results were attributed to the difference in mobility of the terpolymers, as estimated from reputation theory of De Gennes. The results provide a promising route for tailoring polishing properties of silyl acrylate-based SPCs.