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Antifouling coatingsSnake oil & commercial secrets

Patrick Cahill

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A challenging problem…

https://doi.org/10.1038/s41529-023-00370-5

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A challenging problem…

https://doi.org/10.1016/j.porgcoat.2007.01.017

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….for the ages

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Modern antifouling approaches

https://doi.org/10.1039/C5TB00232J

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Biocide-based coatings

https://doi.org/10.1155/2022/2435756

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Organic primary biocide

Organic booster biocide

Metallic primary biocides

Organic booster biocides

Metallic primary biocides

Organic booster biocide

Biocide-based coatings

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https://doi.org/10.1016/j.porgcoat.2007.01.017

Biocide-based coatings

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Biocide-based coatings

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Silicone-based foul-release

https://doi.org/10.1039/C5TB00232J

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Fluorine-based foul-release

https://doi.org/10.1021/cr200350v

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PEG-based attachment prevention

https://doi.org/10.1039/C5TB00232J

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Hybrid foul-release

https://doi.org/10.1021/cr200350v

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Some commercial foul-release

https://doi.org/10.1021/cr200350v

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Primers and tie coats

https://doi.org/10.1039/C5TB00232J

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Making sense of the options

Type

Sub-type

Relative cost

Lifespan

Vessel speed

Minimum operational profile

Biocidal

Soluble-matrix

Low

12 – 24 months

1 – 30 knots

Sporadic use

Self-polishing co-polymer

Medium

12 – 36 months

1 – 30 knots

Sporadic use

Insoluble-matrix/hard

Low

12 – 18 months

>10 knots

Sporadic use

Foul release

Silicone-based

High

24 – 60 months

>15 knots

Regular use

Fluoropolymer-based

High

24 – 180 months

>10 knots

Regular use

Other

Prevention (bubbles, UV)

Medium

Indefinite

Any

Any

Regular cleaning

Low-Medium

Indefinite

Any

Any

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Labels and MSDS

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Labels and MSDS

Primary biocide

Soluble matrix

Booster biocide

Solvents

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Some emerging technologies

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Further reading

Almeida, E., Diamantino, T. C., & De Sousa, O. (2007). Marine paints: the particular case of antifouling paints. Progress in Organic Coatings59(1), 2-20.

NZ EPA (2013). Application for the Reassessment of a Group of Hazardous Substances under Section 63 of the Hazardous Substances and New Organisms Act 1996 26 June 2013. https://www.epa.govt.nz/assets/FileAPI/hsno-ar/APP201051/720402e41b/APP201051-APP201051-Decision-Final.pdf

Lejars, M., Margaillan, A., & Bressy, C. (2012). Fouling release coatings: a nontoxic alternative to biocidal antifouling coatings. Chemical Reviews, 112(8), 4347-4390.

Nurioglu, A. G., & Esteves, A. C. C. (2015). Non-toxic, non-biocide-release antifouling coatings based on molecular structure design for marine applications. Journal of Materials Chemistry B, 3(32), 6547-6570.

Cahill, P. L., Moodie, L. W., Hertzer, C., Pinori, E., Pavia, H., Hellio, C., & Svenson, J. (2024). Creating new antifoulants using the tools and tactics of medicinal chemistry. Accounts of Chemical Research, 57(3), 399-412.

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Questions?