Can resin displace water in chipboard?

[MarkJ]

I am just gathering background knowledge so please help with this information.

Will epoxy resin displace water in damp expanded non-structural chipboard?
Or will the water stop resin from adhering to the wood fibre.
If water is left in the wood and the resin infiltrates around it stopping it from evaporating what will happen?

Thanks

[JeffBurright]

When you say displace, what role does gravity take? Does the water have a low point to escape from? My understanding has always been that epoxy will not displace water in wood fibers, and like you said it would prevent saturation into wood and overall adherence.

It was explained to me that epoxy makes a mechanical bond -- like microscopic velcro -- and the degree to which it's able to sink into pores will determine the strength of the bond. This is why it's recommended to rough up a surface with 40-grit before coating with epoxy. The "Git Rot" type products try to seep deeper into wood by mixing epoxy with a solvent thinner, but again I'm doubtful that it can displace water.

One way I've heard about to get water out of wood is to soak the wood in denatured alcohol multiple times. The alcohol binds to the water molecules, and apparently when the alcohol evaporates with its low flash point it can take the water with it. Similarly, the more airflow you can get over the wood, or the more heat you can introduce to encourage evaporation, the better chance you'll get back to dry wood. I used the alcohol method when we had a keel smile that let water into the wood hull, and I was happy with the results. I sprayed it on with a weed sprayer, then sealed the area with visqueen and duct tape and put a shop vac on it to suck the water out.

Big disclaimer here that I'm not an expert, but I have done my fair share of wet/rotten cold molded repair under people who I think knew their stuff. I hope any of this helps.

[Grateful]

Mark,

Moisture will inhibit or stop the cure of most off the shelf epoxy systems.

[MarkJ]

Thanks Jeff. Gives me terrific food for thought.
Its aa bit like a Sherlock Hills 3 pipe problem. I will mull it over a few days

Mark

[GordMay]

Probably not ➥ Penetrating Epoxy Resin - Facts - Test Results

[Snore]

Originally Posted by MarkJ

Thanks Jeff. Gives me terrific food for thought.

Its aa bit like a Sherlock Hills 3 pipe problem. I will mull it over a few days



Mark

You see Watson I have not conducted personal experiments and therefore must rely on empirical data and research by others.

Given that organic material such as you describe is used as core material in decks. And that when repairing areas with sodden core material said is must be removed and replaced. I therefore deduce that the epoxy will not displace the water and water will prevent a proper bonding.

No where did you place my jar of 7% solution???


Sent from my iPhone- please forgive autocorrect errors.

[chris95040]

Originally Posted by Grateful

Mark,

Moisture will inhibit or stop the cure of most off the shelf epoxy systems.

Actually I don't think it will!!

It can certainly interfere with bonding, like others have described, but the epoxy cure itself should be largely unaffected. Maybe the kinetics of it will change a bit.

[MarkJ]

I am grateful to Greatful, Thanking to Gord and can sleep assuring Snore that its not a deck problem.

It's behind the sink where the faucet farrahs. (Boom-tish).
I am trying to replace the tap - a 10 minute job - and the timber under the laminate is damp, and it can not be replaced easily.

So I am thinking things out slowly.

I have just bypassed the sink by removing the faucet and will not use the sink (yippee!) and will work on drying the timber pending the next (miserable) step.

Mark

[JPA Cate]

Mark,

Check out Smith & Co. Penetrating Tropical Epoxy. May no longer be in business. But they did fabricate penetrating epoxy, which Jim once did a take off on, thinning it with acetone. Sorry, I don't remember the results of this experiment.

Ann

[Grateful]

Originally Posted by chris95040

Actually I don't think it will!!

It can certainly interfere with bonding, like others have described, but the epoxy cure itself should be largely unaffected. Maybe the kinetics of it will change a bit.

Chris - I believe I stand corrected. Intrigued, I just read a couple of technical papers on the subject and while, as you stated, the kinetics are adversely affected, there is no other inhibition to curing. There appears to be a consensus that epoxy cured in high humidity will be slightly weaker than epoxy cured in a dryer environment, with more microscopic fractures in the matrix.

I based my original comment on a recommendation from an epoxy manufacturer that stressed the need to keep all components, including wood flour, as dry as possible to facilitate curing.

I guess you learn something every day.

Mark, carry on with your soggy sink.

[Wotname]

Hey Mark,

Some more mulling points , based on 25 plus years of observation of owning wooden boats and using epoxies but not a heck of a lot of formal reading .

All wood has water in it. Dry wood might have 10% or more water in it (by weight).

After encapsulating with epoxy, whatever water that was in it, will remain in it forever or until the epoxy coating is removed.

The epoxy will cure but some strength is lost, not a problem in non structural applications.

Wet wood is weaker than dry wood.

Regarding your wet chipboard tap hole, my suggestion (FWIW), remove all hardware, dry the area as much as you can. Air movement is way better than heat but air movement plus heat is best. When it seems dry, repeat drying process for the same amount of time!!!

Wack some epoxy on, watch carefully and before it starts to cure, hit it with some warm air (not too hot). It should thin out a little with the heat and you should see air bubbles in it from the warmed air in the chipboard expanding . Remove the warm air and if possible, blow cold air. The bubbles should cease and the now thin epoxy should be drawn into the chipboard. Now it the time to apply freshly mixed epoxy so that it chemically cures to the first coat.

This is a bit of an an artform to get it just right and in your application, it won't matter if it doesn't play out according Hoyle.

I believe but I don't know that it there is fungual growth (rot) in wood before encapsulation with epoxy, the rot will continue to spread inside the encapsulated piece (assuming enough moisture and air was also encapsulated). But it won't spread to ajoining pieces.

[model 10]

No one seems to be considering the esters which do react to moisture.

[reed1v]

Depends on what type of resin your talking about. Also the method of application and also the ambient temperature. Epoxies could care less about moisture but may trap it.

[Scout 30]

According to CPES acetone will remove the moisture. Saturate it with acetone & then try CPES which also has a high solvent content. A heat gun will also help remove the moisture.

[a64pilot]

If you can dry the wood thoroughly first then take thin epoxy and thin it even more with alcohol or maybe acetone, it will penetrate wood, sound silly, but every one who built fuel powered model airplanes used this method to "fuel proof" the wooden firewalls of models and it works.
Model airplane stuff I know, but get some, try it out first on something else first to see if you like the results, I used to use the high purity alcohol content stuff you get at paint stores, rubbing alcohol has a lot of water in it

http://www.amazon.com/Finish-cure-20.../dp/B001NIC3VW