Epoxy eats Polycarbonate

[Dave Lesser]

I stored some WEST system epoxy resin and hardner in polycarbonate bottles (Cyclone bottles made by Outdoor Products).

A few days later, I found that the 206 Slow Hardener had eaten through the bottle and ran all over my workbench. There was no problem with the 105 Resin or the 205 Fast Hardener.

Hope this saves someone else from making a similar mistake.

[ 05-28-2005, 12:24 PM: Message edited by: Dave Lesser ]

[Bruce Hooke]

Thanks for the tip! I hope the mess you had to clean up wasn't too horrendous.

[Bruce Hooke]

BTW - Another reason to be careful about putting epoxy into clear bottles is that I believe UV does not do the stuff any good, so if it is stored in clear bottles those bottles should probably be stored someplace where they do not get a lot of light.

[Dave Carnell]

Polycarbonate is extremely susceptible to cracking by solvents. Low-density polyethylene (LDPE) is not very resistant. High-density polyethylene (HDPE)is used for detergent bottles because detergents are difficult to contain because they crack LDPE bottles. HDPE is not attacked by any common fluids. Polyethylene terephthalate (PETE) and PVC are attacked by many fluids. I use large detergent jugs to store epoxy resin and smaller detergent bottles to store and dispense hardeners and working quantities of resin.

Metal cans corrode; only glass and ceramics are forever resistant, but subject to breakage.

[Charles Neuman]

I have discovered that plastic containers are well-labelled on the bottom. Under the recycling symbol, it tells you what kind of plastic it is. You might need to look up the abbreviation. Here is a link to a site that lists many common abbreviations:
http://www.export911.com/ref/plasAbbr.htm

I have a question on two more materials: nylon and polypropylene.

Nylon is the material for the squeeze bottles from Lee Valley. Woodworker.com also sells empty glue bottles, but it doesn't list the material they are made of. (And by the way, my Titebond glue comes in a HDPE container.)

Polypropylene (PP) is the material for some nice screw-top food containers from the grocery store. I had stored resin in one, and there were no problems. But I'd like to be sure before I use them again, especially with hardener.

Anyone know about nylon or polypropylene?

Thanks,

Charles

[Frank Wentzel]

Not that I am suggesting using polycarbonate after this alert, but I have had System Three epoxy and medium hardener in polycarbonate bottles for over a year. I put some in "Nyquil" bottles to do a job (which never got done) at my brother's. System Three must use a much less aggressive hardener system.

/// Frank ///

[Bill Perkins]

I've been told that the 2 to 1 mixes in general have less dangerous , less reactive hardeners .

I've also been told that the hardeners of high ratio mixes are more negatively affected by the acidity of some oak .Maybe that's why I've had such good luck with T-88 (a one to one mix )bonding oak .

[martin schulz]

...start to learn proper planking & caulking :D

[Ken Hutchins]

These problems have been mentioned before, what I don't understand is why do people store things in containers other than what the manufacturers supply them in. They manufacturer knows what is the best storage container and the container is identified as to what it is. Putting anything in other containers leaves you liable to container and product failures and the possibility of you or someone else not knowing what is in the container which could result in a safety issue. Safety and medical personnel need to know what the chemicals are in the event of an emergency, so if you do use other containers make sure you identify the container with ALL the information on the original containers.

[Ken Hutchins]

Martin, :D :D :D :D

[igatenby]

the possibility of you or someone else not knowing what is in the container Agreed ..... I use a soft drink bottle on the boat as a pee bottle. I suppose I should re-label it?

Ian

[Frank E. Price]

All we need now is something that will eat epoxy, perhaps a relative of the polyestermite if not a chemical.

Frank

[pjwalsh]

A solvent is a relative thing - depends on the relative Cohesive Energy Density of the materials in question. If two liquids have similar CED's they will become a solution when mixed, if a liquid and thermoplastic solid (not crosslinked) have similar CED's the liquid will be very likely to dissolve the solid or at least cause crazing given enough time.

Would not surprise me to find that epoxy crosslinking agents are aggresive to polycarbonate considering that they are small molecules designed to be soluble in epoxy resins which are based on the same bisphenol-A monomer that polycarbonate is polymerized from. As previously mentioned polycarbonate is extremely susceptible to environmental stress cracking or crazing from a variety of solvents and near-solvents.

Two part epoxies with 2:1 or 1:1 ratios are likely to be less aggressive because the crosslinking agent has been diluted with nonyl phenol or other non-reactive diluents to give the easy mixing ratio and lower viscosity while maintaining the stoichiometric balance between epoxide end groups and reactive amines

I would recommend high density polyethylene containers as the best choice for repackaging resins and hardeners.

[ 07-25-2005, 01:30 PM: Message edited by: pjwalsh ]

[Dave Carnell]

HDPE solved the problem of solvent stress cracking with products such as laundry detergents. Polypropylene is equally good. Nylon bottles are not common and nylon's reactivity probably makes it unsuitable. Polycarbonate is attacked by many solvents and not a good material for storing epoxy. I have used dishwashing liquid bottles (HDPE) for storing working quantities of epoxy and hardener for years.