Talk:Epoxy/Archive 2018

Latest comment: 5 years ago by Bruce L. Burton in topic Epoxy


Krazy Glue

I Heard Krazy Glue Will Melth Through Epoxy. I Put Krazy Glue On My Surfboard Which Has An Epoxy Covering And It Turned White. It Is One Of The Aviso Boards That Are Made Of Carbon And It Costy Me About $1220 So I'm Pretty Worried About It —The preceding unsigned comment was added by 67.169.154.107 (talk) 23:10:00, August 18, 2007 (UTC)

   Gosh, and i had heard that those surfin' dudes were highly skilled and really cautious!
--Jerzyt 03:40, 2 August 2018 (UTC)

Epoxy Removal

I believe Epoxy is also used in electronics for security, making the electronic component under a dob of epoxy very difficult to get to and be tampered with. Can anyone else vouch for this? And, how does one remove epoxy? Or is it not possible? Matejhowell 17:39, 31 January 2006 (UTC)

In the pipe coating industry, the applied epoxy coating (rejected during QA/QC) is removed by burn-off at a temperature of 700 to 750° F for about 6 hours in an air circulating oven. Another method of removing epoxy coatings from small aras is by soaking the area in a suitable solvent such as Methyl Ethyl Ketone (MEK) or Xylene. ~~ Penguine_s February 5, 2006

For larger areas, such as in decorative collector's displays of coins or other objects embedded in clear epoxy resins, one will find MEK, Xylene and most organic solvents completely ineffective in dissolution of epoxy. <Ken Forbes April 13, 2006>

Air temperature cured epoxy can be "melted" by applying heat. Michael

Crosslinked epoxies are not soluble in any solvent, they only swell depending on the solvent used. Amine-cured epoxies may be destroyed by acetic or formic acid, pure or diluted by a suitable solvent (dichloromethane e.g.). I don't exspect vinegar to be suitable for removing epoxy mixtures, because epoxy resins are insoluble in water. It only may dissolve amine hardeners by forming a salt with the amines. On the other hand, acetone dissolves epoxy resins but often forms insoluble compounds with amines... I recommend alcohols (ethanol, isopropanol). --FK1954 (talk) 15:16, 14 January 2009 (UTC)

   Thanks for your attempt to clarify. Readers should bear in mind that the vinegar (which you dismiss as probaby unsuitable) is a solution of acetic acid in water. "Dammit, i'm a physicist, not a chemist", but our discussion of the glacial form at Acetic acid suggests that how much dilution by water is likely to be problematic will depend more on thoroughness of curing, and on which epoxy compound is under discussion.

Anecdotal testimony has a solution of triethanolamine in CHCl3 and I think it was N-MePyrrolidone being used by military contractors during the 60's to dissolve the potting around Soviet chips for reverse engineering. Please do not do this at home -chlorinated solvents may attack metal. I believe in a pressure vessel but temperatures were not (too) extreme.71.31.152.220 (talk) 20:21, 23 August 2012 (UTC)

   We do discuss triethanolamine; your trichloromethane solvent for it is much clearer if you mark up the formula as CHCl3 (tho i wish it were more clearly distinct, at least on my screen from CHCI3; hmm, IlI).
--Jerzyt 03:31, 2 August 2018 (UTC)
   Oh, yeah, hmm; do we distinguish e.g. pressure cooker, pressure vessel, and i think autoclave?? Yeah, DON'T TRY IT AT HOME.
--Jerzyt 03:31, 2 August 2018 (UTC)

Indeed, don't try these at home either, read the safety data sheets, etc. Depending upon the glass transition temperature of the epoxy formulation (if known), and the substrate and component types (wood? electronics to be looked at, etc.) warming to about ten degrees C above the glass transition temperature will often allow one to mechanically abrade, cut, or otherwise remove much of the cured epoxy resin. Such bulk removal can be helpful prior to applying other methods (following). Methylene dichloride (chloroform has already been mentioned) is particularly good at swelling and softening cured epoxy resin and in some cases will cause spontaneous spallation, given enough time. Doing this in a kettle or flask with a reflux condenser will speed things along. Similarly, benzyl alcohol (arguably safer to use than the chlorinated solvents) is quite good at swelling amine-cured epoxy resins. The swelling reduces the glass transition temperature, often below room temperature, and the modulus drops a couple of orders of magnitude, making the cured resin "cheesy" and much more easily removable. The two methods, heat and solvents, may be used together for optimal effect. Filled or composite systems may take longer to remove. Bruce L. Burton (talk) 20:19, 4 September 2018 (UTC)

Epoxy

How does Epoxy hold up when it comes in contact with Gasoline or Ethanol? —Preceding unsigned comment added by 64.203.237.78 (talk) 16:06, 29 January 2009 (UTC)

This depends on the composition of the resin, but usually nearly nothing will happen. --FK1954 (talk) 17:47, 29 January 2009 (UTC)
  The more cautious among interested readers will want to read carefully our articles on Usuality, Nearly nothing, and Barely anything.
--Jerzyt 00:50, 2 August 2018 (UTC)

As noted results may vary widely depending upon the structure of the polymer network formed. I've found that most systems, when fully cured at a one to one stoichiometry, will be quite resistant to gasoline but may succumb to ethanol and, more so methanol. Bruce L. Burton (talk) 20:24, 4 September 2018 (UTC)