Enhanced antifouling property of polydimethylsiloxane-CuO nanocomposite in marine environment

Abstract

Increased adhesion and biofilm formation by marine microalgae as well as inhibition of settlement of invertebrate larval forms on polydimethylsiloxane (PDMS) foul release coatings is a challenge to overcome. Copper oxide nanoparticles (CuO-NP) were synthesized by a wet chemical precipitation route and incorporated into PDMS foul release surfaces to improve its anti-microfouling nature. In situ antifouling performance of PDMS-CuO nanocomposite (NC) was evaluated in coastal waters and compared with plain PDMS surface. Adhesion and settlement of microalgae and macrofoulers and their succession were monitored for 7 and 90 days respectively. Plain PDMS surfaces were abundantly colonized by microalgae (1.3 × 103 cm−2), wherein significant (p < 0.05) reduction (1.76 × 102) was observed with PDMS-CuO NC. In addition, CuO reinforcement significantly (p < 0.05) reduced the biofouling load and surface area coverage upto 1.6 ± 0.22 Kg m−2 90 day−1 and 27.5 ± 4.5% respectively, whereas plain PDMS surfaces experienced 10.6 ± 1.5 Kg m−2 90 day−1 and 89.6 ± 7.96% respectively. Incorporation of CuO nanoparticles as nanofillers into PDMS matrix offers a promising antifouling alternative to inhibit algal fouling as well as larval settlement by imparting toxicity at the surface through release of metal ions.