Amine Blush and Rustoleum Primer/Paint??

Having issues with amine blush, will it affect the bond with the Rustoleum primer? Here?s what happened, I rinsed the epoxy surface with a Scotchbrite pad and warm water. Wiped the damp surface with paper towels to dry then re-wiped with denatured alcohol. Sanded and repeated the cleaning procedure and I still have an amine blush film being wiped off from the epoxy surface?? Has anyone had this experience? Would it be okay to apply primer to this surface?

Re: Amine Blush and Rustoleum Primer/Paint??

It shouldn't do that if it's fully cured and the blush is not thick, it will just be a thin film on the surface that can easily be removed. There's some odd going on.

Re: Amine Blush and Rustoleum Primer/Paint??

pictures.....

Re: Amine Blush and Rustoleum Primer/Paint??

Have you put that epoxy coating out in the sun to see if that helps?

Re: Amine Blush and Rustoleum Primer/Paint??

Thanks for the replys.

bgc said:

pictures.....

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I'll try to get some tonight.

jigngrub said:

Have you put that epoxy coating out in the sun to see if that helps?

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Thought about it but it's raining too much over here in the islands and the UV's wouldn't be too good for the epoxy (maybe after the paint job).


In further researching my issue I’ve found out that I probably have “Amine Bloom”, which is hardener (amines) that has not chemically reacted with the resin in the mixture and will surface as free amines until the epoxy is fully cured. These “free amines” will remain “free” on the surface or react with CO2 or moisture in the air forming “Amine Blush”. So, I guess I’ll have to wait till the epoxy is fully cured at room temperature (about a month) or I can try “post curing” it with a heat source to speed up the process (it should also give the epoxy more strength) before I can do any final prep for priming.

Re: Amine Blush and Rustoleum Primer/Paint??

96720 said:

Thanks for the replys.



I'll try to get some tonight.



Thought about it but it's raining too much over here in the islands and the UV's wouldn't be too good for the epoxy (maybe after the paint job).


In further researching my issue I?ve found out that I probably have ?Amine Bloom?, which is hardener (amines) that has not chemically reacted with the resin in the mixture and will surface as free amines until the epoxy is fully cured. These ?free amines? will remain ?free? on the surface or react with CO2 or moisture in the air forming ?Amine Blush?. So, I guess I?ll have to wait till the epoxy is fully cured at room temperature (about a month) or I can try ?post curing? it with a heat source to speed up the process (it should also give the epoxy more strength) before I can do any final prep for priming.

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If you can catch a hot sunny day, take it outside and put another coat on it. You'll have to work quickly and mix smaller batches but it will quickly.

I've been waiting for the UVs to break down some epoxy I spilled and dripped on my patio last September, stuff is still hard as a rock and pulls up the concrete if you try to remove it. A day in the sun won't hurt your epoxy.

Re: Amine Blush and Rustoleum Primer/Paint??

Sorry bgc, no pics. There isn’t really much to see on the hulls surface. The epoxy surface is hard with very little haze that can only be seen at certain angles (wouldn’t show up or be recognizable in photos).

Hey jigngrub, guess I’m getting overly cautious on all the do's and don’ts with epoxy. If the weather clears over the weekend I’ll let the boat out to catch some sun.

I did a warm water wash, scrub and paper towel dry and there was amine blush residue again. So, I guess the amines are still permeating through the epoxy surface and creating the blush.

Re: Amine Blush and Rustoleum Primer/Paint??

The weather turned nice yesterday so I hope the curing process is stepping up. Did the scrub and wash again and there was residue but, less than the day before. Hope this means it'll be fully cured soon.

epoxy resin in a nutshell

epoxy resin in a nutshell

Here?s a really brief and simplistic over view of ?epoxy resins/hardeners? from what I?ve found doing some ?research?. Epoxy resins are relatively generic in make up. There are many variations to hardeners and their formulas. The main industrial concern is the formation of amine blush that forms on the surface of the epoxy and the negative effect it has on the secondary bond. Amine blush forms when the hardener reacts with the CO2 and moisture (humidity) in the environment. Amine blooms can compound the problem when hardener that has not reacted with the resin in the mixture keeps rising to the epoxy surface and forms an amine blush until it is fully cured. You can let the epoxy sit at room temperature or speed the process with an external heat source (post cure) to fully cure. When cured and preparing the surface to sand (or, testing whether or not the surface has cured) follow what your epoxy system suggests. A general cleaning method would be to use a bucket of warm water and a Scotchbrite pad to scrub and rinse the epoxy surface. And, before the surface dries use paper towels to dry it off. Some suggest the use of a little soap, ammonia or vinegar in the water. The reason for using paper towels and not rags is that it could introduce contaminants that could be in the material or from the laundry cycle. This procedure should have removed all the ?amine blush? and now you?re ready to sand your surface. Put enough bite on the surface by sanding and resist the temptation the feel the surface with your bare fingers and/or hand (you?ll be depositing oils and contaminants to the surface). When done lightly bush and/or vacuum off the dust, you don?t want to wipe the particles back into the surface. You should be ready to apply your next coat.

In conclusion, the more expensive the ?epoxy system? or ?blush free? the epoxy resin is the more refined the hardener is and it should be less prone to the formation of ?amine blush?. To avoid any bonding complications between epoxy layers ?wet on wet? application is advised. Work under ideal conditions as recommended by your epoxy system (avoid cold or humid days). Measure and mix resin and hardener thoroughly to instructed ratios. Use the fastest setting hardener to minimize environmental influences. Allow epoxy to fully cure, different systems have different rates of cure and environmental factors play a big role curing (7 days seems to be the general suggested waiting period). All epoxies, including blush free, recommend washing down and sanding before applying the next coat (when fully cured). These are just some stuff I?ve found that seem to be frequently mentioned in the discussion of epoxy resins.

Re: epoxy resin in a nutshell

Re: epoxy resin in a nutshell

I went with a "blush free" and it still did a bit from the high humidity.

Re: epoxy resin in a nutshell

Re: epoxy resin in a nutshell

The weather has been nice the last couple of days and I let the hull out to catch some sun. Seems like the heat (85+ degrees F) and relatively low humidity (upper 50%) has given the epoxy some badly needed curing help. The surface has become clear of blush. I'll give it one more check this morning, if it's good I'll give it a sand and lay a coat of primer on since the weather is still holding.

Re: epoxy resin in a nutshell

Re: epoxy resin in a nutshell

I figured that would help.

I mix my epoxy in the garage and take it out into 90* heat and apply it, the epoxy outside goes like lightning without a hint of blush and when I go back into the garage my stir stick will have the amine blush. The epoxy will be hard but it will have a sticky film on it, put stick out in the sun and the blush goes away.

Re: epoxy resin in a nutshell

Re: epoxy resin in a nutshell

jigngrub said:

I figured that would help.

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Yeah, jigngrub, thanks for the tip.

Really wanted to sand and prime today but I still have some blush coming through. No sense in rushing the process so, I'll let the hull catch a little more rays today hope it'll do the trick.

Re: epoxy resin in a nutshell

Re: epoxy resin in a nutshell

Your gonna have to Grind .. not sand .. but Grind until you have it down to NO Shiny spots.

Forget about wiping..Grind ..then layup.

YD.

Re: epoxy resin in a nutshell

Re: epoxy resin in a nutshell

Yacht Dr. said:

Your gonna have to Grind .. not sand .. but Grind until you have it down to NO Shiny spots.

Forget about wiping..Grind ..then layup.

YD.

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YD wish I could grind, it would be better than having to wait for this layer to cure. What's curing is just a "barrier coat" I applied to the vinylester hull that I want to prime and paint with Rustoleum. When I sand I'm able to get a dull finish but, when I wash the area to be certain I don't have any "blush" resurfacing I get some residue. So, I'm waiting for the epoxy to totally cure and won't have an amine interface with my primer coat.

Re: epoxy resin in a nutshell

Re: epoxy resin in a nutshell

What kind of epoxy did you use ? ..

It should have cured way before now..

Sure you mixed it right ? ..

Something is just not right here .. you should have been able to de-blush and move on the next day ..

I still suggest grinding it for prep.

YD.

Re: epoxy resin in a nutshell

Re: epoxy resin in a nutshell

You have an odd combination of products being used, VE, Epoxy and Rustoleum.

VE is great for a hull and doesn't really need a barrier coat of epoxy, but if you planned to leave in it the water all the time it wouldn't hurt. One coat of epoxy won't help much though, you typically need several coats to build up a layer thick enough to prevent water from passing through it.

Then the Rustoleum, for a low cost cheap paint it works OK, but it's not designed or recommended for continuous immersion in water, day use seems to be OK though.

So you have VE (great resin), Epoxy (even better), then Rustoleum (the cheapest thing around), I'm a little confused.

What size is this boat and how do you plan to use it?

Re: epoxy resin in a nutshell

Re: epoxy resin in a nutshell

Yacht Dr. said:

What kind of epoxy did you use ? ..

It should have cured way before now..

Sure you mixed it right ? ..

Something is just not right here .. you should have been able to de-blush and move on the next day ..

I still suggest grinding it for prep.

YD.

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YD, The epoxy system I’m using is Fiberglass Hawaii 4:1 Multi Epoxy Resin. The resin is made by DOW, D.E.R.*324 Epoxy Resin and the hardener is made by Air Products, Ancamine 1796 Curing Agent.

Yes, I’m sure I measured and mixed the epoxy correctly. The humidity was a little high during application but less than 85% (I did have some “cloudiness” when mixing).

ondarvr said:

You have an odd combination of products being used, VE, Epoxy and Rustoleum.

VE is great for a hull and doesn't really need a barrier coat of epoxy, but if you planned to leave in it the water all the time it wouldn't hurt. One coat of epoxy won't help much though, you typically need several coats to build up a layer thick enough to prevent water from passing through it.

Then the Rustoleum, for a low cost cheap paint it works OK, but it's not designed or recommended for continuous immersion in water, day use seems to be OK though.

So you have VE (great resin), Epoxy (even better), then Rustoleum (they cheapest thing around), I'm a little confused.

What size is this boat and how do you plan to use it?

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ondarvr, First off the boat is 1962 16’ Glasspar Avalon that I’m trying to restore as a fishing boat and will only be in the water for day use. The reason for applying the “barrier coat” was to fill very fine imperfections and pin holes in the hull (the hull seems to have been repaired a few times before) and to put a uniform seal to the surface for the Rustoleum primer to adhere to.

My intention was to use “marine epoxy” paint on the hull but, after researching products and listening to debates on which one to get and which not to get I finally threw in the towel. Not to mention I have very limited access to these products on my island and hazmat restrictions compound issues. So, Rustoleum seems to be the only product that’s readily available (but, not always in stock) for me.

still on hold

still on hold

Well,,,,, same old weather for the past week..... the best it gets is the mid 70's F and RH is between 85&90%. And, the only serious work I can do on the weekends??? Hopefully, I'll get a break soon. Take some vacation time when the weather becomes stable. Another minus for living on the windward side of an island in the middle of the Pacific.

Re: still on hold

Re: still on hold

I dunno man .. If it was mixed properly and both parts are for the same system .. then it should have cured without having any more blush surfacing.

Have you tried soap and water scrubbing on a spot or two ?

YD.