Hydrophobic coatings

I finally found a report on how super-hydrophobic materials affect bio-growth.

http://www.ornl.gov/adm/partnerships/tech/superhydrophobic/docs/ABCs_of_Superhydrophobic.pdf

The news is excellent. Go to page 27 in the report.

Results after 8 weeks of testing at the Battelle Florida Materials Research Facility:
– Quote by Dr. Henry Pate of Battelle: “In all the years that I have been testing material and
coatings, I have never seen anything that prevents biofouling this well”.

 

DDT is a tricky case. From one aspect it is most certainly a nasty chemical that can accumulate in humans and the food chain. From another aspect, the ban on DDT is probably responsible for hundreds of thousands of deaths in Africa and elsewhere.

 

Good find, reddwarf! Thanks.

 

Any update? Did you get a chance to test the coating?

 

Tom the rower - I just looked up the Everglades Challenge and I see it starts tomorrow. That is a very interesting and challenging race. Good luck, let us know how it goes.

 

Sorry to not respond right away, I was busy sailing in the contest. I finished my 60 miles at 11:30 pm. Great to have following winds ! As to the Ultra Ever Dry, I met with an engineer for the company, who said they had done controlled studies with a 35 ft powerboat before and after application and they had concluded that it actually slowed the boat down by about 1 knot. He said they are postulating that the nano particles act like hair and slow the boat down. Said I might be happier using rain x.

 

Rain X, interesting idea.

Is it okay on polyester gelcoat?

It's designed for silica glass, right?

Congratulations on finishing the race.

 

@red dwarf
i don't know if the question regarding barnacles has been answered yet...

i studied biology for some time and i know that these creatures produce some sort of biological glue to stick to their respective substrate.
this glue "cures" very much like blood and the proteins involved are similar or even the same, but comes as a fluid...
and even if the curing only takes fractions of a minute in an underwater environment - it should be repelled by this ever-dry stuff...

but consider that the coating must not have any, even the smallest microscopic leaks because the larvaes of barnacles are microscopic and they would definitely find this weak spots in the coating...

btw: epoxy is a quite similar substance than the barnacle glue - even if a lot weaker - but if epoxy is not adhering to a coated surface, then barnacles should also have it very difficult...

 

Thanks for the info. In my searching I have seen some theories that say not wetting the surface increases drag. Do you know how fast this 35 ft power boat was going? I don't care about losing 1 knot out of 40 knots (2.5%) but losing 1 knot out of 10 knots (10%) would not be so good.

My main interest is the possibility of long term resistance to bio-growth. I can live with a small loss in speed if it pays for itself in years of clean bottom. In fact if the loss in speed is just a few percent it will probably be the same loss as running a less effective bio resistant paint.

 

If you can get a small sample that you could adhere to you hull, let cure, then try to puncture it with a sharp stick that could tell you much about if it will resist wildlife growth.

 

My main interrogation is how this coatting will resist on sea water on the long term.
Secondly, Ultra Ever Dry is ultra ever expensive if you want to coat all your hull surface.

And as discuss previously, it is quite non eco-friendly