Abstract
Polydimethylsiloxane (PDMS) could be used to improve the antifouling properties of the fouling release coatings based on polyurethane (PU). A series of polydimethylsiloxane-modified polyurethane coatings were synthesized with various PDMS contents, using the solvent-free method. The effects of PDMS content and seawater immersion on the chain structure and surface morphology were investigated by confocal laser scanning microscopy (CLSM), atomic force microscopy (AFM), Fourier transform infrared spectroscopy (FTIR), differential scanning calorimetry (DSC), thermogravimetric analysis (TGA) and X-ray diffraction (XRD). Based on the measurements of contact angles of deionized water and diiodomethane, surface free energies of the coatings were estimated according to the Owens two-liquid method. The PDMS-modified polyurethane exhibited lower surface free energy and a lower glass transition temperature than polyurethane. The presence of PDMS increased the degree of microphase separation, and enhanced the water resistance of the coatings. The optimum amount of PDMS reduced the elastic modulus and increased the ductility of the coating. The presence of PDMS benefited the removal of weakly attached organisms. Panel tests in the Yellow Sea demonstrated the antifouling activity of the PDMS-modified polyurethane.
Highlights
Biofouling is the undesirable growth of marine organisms on artificial structures immersed in the ocean
Traditional antifouling coatings often contained tin and copper species, which are or will be banned because of their environmental risks [5]. This has promoted the development of environmentally friendly antifouling coatings
Careful design of the silicone-polyurethane copolymer structure is important for obtaining a coating with favorable surface, mechanical, and adhesive properties
Summary
Biofouling is the undesirable growth of marine organisms on artificial structures immersed in the ocean. Ships hulls fouled by marine organisms experience frictional drag, increased fuel consumption, longer voyage times, higher dry-docking frequency, and increased fuel emissions [1,2]. Antifouling coatings are applied on ships’ hulls to act against biofouling. Traditional antifouling coatings often contained tin and copper species, which are or will be banned because of their environmental risks [5]. This has promoted the development of environmentally friendly antifouling coatings. Fouling-release coatings are a mature technology that has been commercialized. They do not necessarily inhibit the attachment of marine organisms, but allow only weak bonding between marine organisms and the surface. Most of investigations showed that there are currently two key types of fouling-release coatings, namely fluoropolymers and silicone-based polymer coatings [1,7]
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Free) 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call
