Self-repairing silicone coatings with controlled release of organic antifoulants have excellent antifouling/fouling release performance even under static conditions.

Marine biofouling is a problem for marine industry and maritime activities. We have prepared polyurethane with poly(dimethylsiloxane) (PDMS) main chains and N-(2,4,6-trichlorophenyl) maleimide (TCM) pendant groups via a combination of a thiol-ene click reaction and a condensation reaction and studied its properties. The polymer has low surface energy and a high water contact angle. When TCM content in bulk is high enough, sufficient antifoulant groups can be exposed on the surface. Our study reveals that such polymeric surface can effectively inhibit the adhesion and colonization of marine organisms such as bacteria (Micrococcus luteus), diatom Navicula, and barnacle cyprids. Particularly, marine field tests demonstrate that the polymer has excellent antibiofouling performance in 110 days.

Polydimethylsiloxane (PDMS)-based coatings are environment-friendly systems for marine fouling release. However, they usually exhibit low adhesion to substrate and poor mechanical properties, which limits their applications. We have developed polyurea (PUa) with PDMS as soft segments and 1,6-hexanediamine as hard segments via a polycondensation reaction. Such polyurea (PDMS-PUa-x) is hydrophobic with water contact angle above 90° and has low surface energy (25–29 mJ·m–2). In particular, its adhesion to the substrate (>1.0 MPa) and modulus (>80.0 MPa) are significantly improved in comparison with those of PDMS coatings. Laboratory bioassay and marine field tests demonstrate that PDMS-PUa-x has good fouling release performance.

No abstract

Black liquor is an attractive option for the generation of biofuel and fine chemical intermediates.