Development of Polydimethylsiloxane and Polyurethane (PU/PDMS) Based Coating for Foul-Release Applications

The current research work deals with the development of environment-friendly coatings with fouling release ability based on polydimethylsiloxane (PDMS) and polyurethane (PU) for marine applications. PU was synthesized using isophorone diisocyanate (IPDI) and polyethyleneglycol (PEG) and blended with PDMS. FTIR spectroscopy confirms the synthesis of PU and the successful interaction of PDMS components with the PU domain. The properties of PU/PDMS based films were evaluated in terms of mechanical strength, solubility, chemical resistance, water absorption, thermal stability, glass transition temperature (Tg), and morphology. The NCO:OH ratio of 1.4:1 and PU:PDMS ratio of 85:15 was found to be the optimum composition. GPTMS-treated nanosilica was also incorporated at a loading of 2 wt% within the PU/PDMS system. Subsequently, the optimized formulation of PU/PDMS was coated on metal substrates and exposed to marine water containing algal colonies. The modification of the PU/PDMS blend with nanosilica was also investigated to evaluate the quality of the coating.