Amphiphilic Polyphosphonate Copolymers as New Additives for PDMS-Based Antifouling Coatings

Abstract

Poly(ethyl ethylene phosphonate)-based methacrylic copolymers containing polysiloxane methacrylate (SiMA) co-units are proposed as surface-active additives as alternative solutions to the more investigated polyzwitterionic and polyethylene glycol counterparts for the fabrication of novel PDMS-based coatings for marine antifouling applications. In particular, the same hydrophobic SiMA macromonomer was copolymerized with a methacrylate carrying a poly(ethyl ethylene phosphonate) (PEtEPMA), a phosphorylcholine (MPC), and a poly(ethylene glycol) (PEGMA) side chain to obtain non-water soluble copolymers with similar mole content of the different hydrophilic units. The hydrolysis of poly(ethyl ethylene phosphonate)-based polymers was also studied in conditions similar to those of the marine environment to investigate their potential as erodible films. Copolymers of the three classes were blended into a condensation cure PDMS matrix in two different loadings (10 and 20 wt%) to prepare the top-coat of three-layer films to be subjected to wettability analysis and bioassays with marine model organisms. Water contact angle measurements showed that all of the films underwent surface reconstruction upon prolonged immersion in water, becoming much more hydrophilic. Interestingly, the extent of surface modification appeared to be affected by the type of hydrophilic units, showing a tendency to increase according to the order PEGMA < MPC < PEtEPMA. Biological tests showed that Ficopomatus enigmaticus release was maximized on the most hydrophilic film containing 10 wt% of the PEtEP-based copolymer. Moreover, coatings with a 10 wt% loading of the copolymer performed better than those containing 20 wt% for the removal of both Ficopomatus and Navicula, independent from the copolymer nature.

Fabrication of Poly(vinyl alcohol)/Chitosan Composite Films Strengthened with Titanium Dioxide and Polyphosphonate Additives for Packaging Applications

“…Thus, the co-existence of the hydroxyl groups in both PVA and CS, doubled by the presence of amino groups in CS, can produce intermolecular interactions, which may result in an improvement of performances of PVA composites. The use of polyphosphonate containing sulfur and phosphorus in the main chain and in the side chain in phosphaphenanthrene-type heterocycles is expected to induce thermal stability in the composite, then, to synergistically bring its own antimicrobial contribution to the composite, as was described in few studies in the recent past [ 39 ].…”

Nitroxide-Containing Amphiphilic Random Terpolymers for Marine Antifouling and Fouling-Release Coatings

“…44,47 Adults were collected in S. Rossore-Migliarino-Massaciuccoli Regional Park (Pisa, Italy) and acclimated in the laboratory to test conditions (temperature 20 ± 2 °C, water salinity 30 ppt, pH 8.12, 14 h light: 10 h dark photoperiod) prior to use. 44 Larval culture for the test setup was as follows: male and female gamete release was obtained by gently breaking the calcareous tubes, removing the serpulid worms and placing them singularly in the wells of 24-well plates filled with 0.45 μm filtered seawater (salinity 30 ppt). After gametes were released, sperms from different males were pooled, and the final concentration was measured with a Burker cell-counting chamber and an optical microscope.…”

Blood Compatibility of Hydrophilic Polyphosphoesters

“…Based on such results, PPEs have been proposed for different biomedical applications, for example, protein–polymer conjugates, − nanocarriers loaded with drugs, antimicrobial agents, gene vectors, or hydrogels for tissue engineering . In many applications, PPEs are proposed as biodegradable alternatives to poly­(ethylene glycol) (PEG), ,, which is nowadays the most used water-soluble polymer in nanomedicine to prolong the drug lifetime and efficiency . In this context, the evaluation of PPE blood compatibility is an important step to translate these in vitro results to in vivo applications.…”