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Catching up on my science reading I found this this morning.

 

https://www.pnas.org/content/116/10/4297.abstract?etoc

 

Macrostomum lignano - free-living, hermaphroditic flatworm of the intertidal sand in the Adriatic Sea.is a well known lab animal. It has a duo-gland adhesive system that allows it to repeatedly attach to and release from substrates in seawater within a minute. We propose an attachment–release model where Mlig-ap2 attaches to the substrate and Mlig-ap1 exhibits a cohesive function. A small negatively charged molecule is secreted that interferes with Mlig-ap1, inducing detachment. These findings are of relevance for fundamental adhesion science and efforts to mitigate biofouling.

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Somewhat related: Many years of marine biology research resulted in finding a substance that 'tells' barnacles "not here" without harming them (it is claimed). Now this substance is used in at least two brands of antifouling paint. The Danes have just started marketing their paint to the pleassure boating market -- at least here in Sweden.

 

The substance they use is marketed by this company by the name Selektope: https://selektope.com/

 

/Martin

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I have been looking into antifouling chemicals for some time and have concluded that Selektope is our best bet for an effective additive that may be acceptable to our regulators, supposedly very effective against Barnacles and Tube worms. 

A number of currently used additives are no longer approved for inclusion in a couple of years, quite a few are already banned.

Maybe 10 or 15 years ago I saw two posters on a yacht club notice board, one government agency announcing their desire to remove all toxic chemicals from the marine antifouling market, another government agency announcing their concern about the spread of foreign marine organisms. They obviously weren't working together.

I have had some correspondence with Hempel, I used two different paints as a side by side experiment this season, one was a Hempel product. Hempel have a product that includes it but are not planning on bringing it in, short sighted I feel as I think they could corner the market if it was available:

"Yes, Hempel does use Selektope as an additive in Globic 9500. This product is not available in NZ currently."

see https://selektope.com/ for some interesting reading.

The additive has been through a number of approval processes world wide and should be relatively easily introduced here.

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Reason Hempel are not using it here is that Globic is for Commercial Shipping. They use a slightly different chemistry for Commercial applications. It is easy to forget just how fast a ships hull is traveling though the water and often a large surface area of AF maybe above water for extended times. Globic is not available in smaller than 44Gal drums.

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It's not quite as straight forward as it sounds.

If you want to spray on AF, you can only do that with High pressure airless. It goes on real quick and a small Hull would not warrant to cost of equipment, the speed it applies at and the thinners required for the clean up at the end.

You cannot spray AF without thinning and you must not thin AF.

 

For top coats, air would be best for small boats up to say 35ft. Airless once again, is used on very large area's.

The benefit of roll and brush is that you do not need thinners, which is a saving and if you are using two pot paints, it tends to be far safer to apply. If you spray, you need all sorts of safety gear and you need to think about where over spray may go. And yep, you lose about 10% of paint to over spray. Possibly a lot more if you are not experienced.

 

A 2mm nozzle will be far too big for a beginner. It throws the paint at the surface. 2mm is usually used for high build products.

 

Forget the Wagner home handyman airless machines. IMO, they don't produce a nice finish.

This one has me scratching my head too. A German fella at Norsand was going to try to import Selektope which uses ivermectin to drive the barnies larva crazy so they cant stick, 10 years service life!! He said he was told it would need to be submitted for testing and approval in NZ even though Europe has done all the testing! Ivermectin is a stock remedy and restricted medicine so he seems to think that's their concern. Rediculous. It should be here now!

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I have been looking into antifouling chemicals for some time and have concluded that Selektope is our best bet for an effective additive that may be acceptable to our regulators, supposedly very effective against Barnacles and Tube worms. 

A number of currently used additives are no longer approved for inclusion in a couple of years, quite a few are already banned.

Maybe 10 or 15 years ago I saw two posters on a yacht club notice board, one government agency announcing their desire to remove all toxic chemicals from the marine antifouling market, another government agency announcing their concern about the spread of foreign marine organisms. They obviously weren't working together.

I have had some correspondence with Hempel, I used two different paints as a side by side experiment this season, one was a Hempel product. Hempel have a product that includes it but are not planning on bringing it in, short sighted I feel as I think they could corner the market if it was available:

"Yes, Hempel does use Selektope as an additive in Globic 9500. This product is not available in NZ currently."[/size]

see https://selektope.com/ for some interesting reading.

The additive has been through a number of approval processes world wide and should be relatively easily introduced here.

My neighbour contacted altex coatings about Selektope and I have a copy of the email I will quote a paragraph here .

 

“We have been aware of Selektope for some years and have carried out some research with varying results . This additive is still under investigation as a consequence to more recent international and does have potential. However , and this is a Hazchem problem , Selektope is not registered for use in Australia or New Zealand at present and there is little likelihood of registration in the near future .”

 

So what the feck is the issue ? Are the paint companies waiting for a competitor to pay for registration and all the pokery jiggery to get it approved ? .

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This one has me scratching my head too. A German fella at Norsand was going to try to import Selektope which uses ivermectin to drive the barnies larva crazy so they cant stick, 10 years service life!! He said he was told it would need to be submitted for testing and approval in NZ even though Europe has done all the testing! Ivermectin is a stock remedy and restricted medicine so he seems to think that's their concern. Rediculous. It should be here now!

Ha that’s my neighbour

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