In the present study, the overall economic impact of hull fouling on a mid-sized naval surface ship (Arleigh Burke-class destroyer DDG-51) has been analyzed. A range of costs associated with hull fouling was examined, including expenditures for fuel, hull coatings, hull coating application and removal, and hull cleaning. The results indicate that the primary cost associated with fouling is due to increased fuel consumption attributable to increased frictional drag. The costs related to hull cleaning and painting are much lower than the fuel costs. The overall cost associated with hull fouling for the Navy's present coating, cleaning, and fouling level is estimated to be $56M per year for the entire DDG-51 class or $1B over 15 years. The results of this study provide guidance as to the amount of money that can be reasonably spent for research, development, acquisition, and implementation of new technologies or management strategies to combat hull fouling.

Economic impact of biofouling on a naval surface ship

'Marine biofouling', the undesired growth of marine organisms such as microorganisms, barnacles and seaweeds on submerged surfaces, is a global problem for maritime industries, with both economic and environmental penalties. The primary strategy for combating marine fouling is to use biocide-containing paints, but environmental concerns and legislation are driving science and technology towards non-biocidal solutions based solely on physico-chemical and materials properties of coatings. Advances in nanotechnology and polymer science, and the development of novel surface designs 'bioinspired' by nature, are expected to have a significant impact on the development of a new generation of environmentally friendly marine coatings.

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Trends in the development of environmentally friendly fouling-resistant marine coatings

Fouling release coatings: a nontoxic alternative to biocidal antifouling coatings.

Polymer brush coatings for combating marine biofouling

Silicone containing copolymers: Synthesis, properties and applications

Paint and Coatings Technology for the Control of Marine Fouling

Amphiphilic copolymers containing different amounts of poly(ethylene glycol)-fluoroalkyl acrylate and polysiloxane methacrylate units were blended with a poly(dimethyl siloxane) (PDMS) matrix in different proportions to investigate the effect of both copolymer composition and loading on the biological performance of the coatings. Laboratory bioassays revealed optimal compositions for the release of sporelings of Ulva linza, and the settlement of cypris larvae of Balanus amphitrite. The best-performing coatings were subjected to field immersion tests. Experimental coatings containing copolymer showed significantly reduced levels of hard fouling compared to the control coatings (PDMS without copolymer), their performance being equivalent to a coating based on Intersleek 700™. XPS analysis showed that only small amounts of fluorine at the coating surface were sufficient for good antifouling/fouling-release properties. AFM analyses of coatings under immersion showed that the presence of a regular surface stru...

https://www.tandfonline.com/doi/pdf/10.1080/08927014.2012.697897

Poly(dimethyl siloxane) (PDMS) network blends of amphiphilic acrylic copolymers with poly(ethylene glycol)-fluoroalkyl side chains for fouling-release coatings. II. Laboratory assays and field immersion trials.

Dynamic mechanical analysis was used to record the behaviour of hydrated and dehydrated byssal threads under tensile stress and during dynamic thermal cycling. Fresh byssi, and byssi aged two weeks prior to testing, were used to further study the effects of age on the mechanical properties of this material. It was found that while older threads demonstrated increased stiffness, age did not necessarily affect their ultimate tensile strength. Dehydration had a more pronounced effect on thread stiffness and also increased the ultimate strength of the material. In their dry state, byssal threads displayed multiple yield points under tension and these, it is suggested, could equate to different phases within the bulk of the material. Dynamic analysis revealed glass transition (Tg) and ecologically relevant operational temperatures for byssi, where their modulus (E') remained constant. These discoveries are related to the ecological function of byssal threads and to the emerging field of biomimetics.

/pdf/tensile-and-dynamic-mechanical-analysis-of-the-distal-hk477huhey.pdf

Tensile and dynamic mechanical analysis of the distal portion of mussel ( Mytilus edulis ) byssal threads

A process to physically deter fouling from a substrate in an aquatic fouling environment, which process comprises forming on the substrate, before exposure to the said environment, a coating composition comprising (i) a curable polyorganosiloxane polyoxyalkylene block copolymer having at least two reactive groups X situated on the copolymer chain and (ii) an organosilicon crosslinking agent and/or a catalyst.

Antifouling coating composition based on curable polyorganosiloxane polyoxyalkylene copolymers

The invention pertains to an anti-fouling composition which comprises a cured or cross-linked polymer free of perfluoropolyether moieties and a fluid fluorinated alkyl- or alkoxy-containing polymer or oligomer. Preferably, the fluorinated alkyl- or alkoxy-containing polymer or oligomer comprises a repeating unit of the general formula: -{[CFR-(CFR)m-(O)n]p-[CFR-O]q]}-wherein n is 0 or 1, m is an integer from 0 to 4, R independently is H, F, CI, Br, or CF3, and the ratio q/p is 0 - 10, and the fluorine-free polymer is an organosiloxane-containing polymer comprising a repeating unit of the general structure -[SiR1R2-O]-, wherein R1 and R2 are independently selected from hydrogen, alkyl, aryl, aralkyl, and a vinyl group.

David Neil Williams

Papers

Paint and Coatings Technology for the Control of Marine Fouling

Poly(dimethyl siloxane) (PDMS) network blends of amphiphilic acrylic copolymers with poly(ethylene glycol)-fluoroalkyl side chains for fouling-release coatings. II. Laboratory assays and field immersion trials.

Tensile and dynamic mechanical analysis of the distal portion of mussel ( Mytilus edulis ) byssal threads

Antifouling coating composition based on curable polyorganosiloxane polyoxyalkylene copolymers

Anti-fouling compositions with a fluorinated alkyl- or alkoxy-containing polymer or oligomer