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HDPE bottle went from round to square?

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Rising Star
What the hell happened? SWIM left lye and naphtha in it overnight and the sides flattened out so it's square with rounded edges now. :shock:


Wouldn't know, but its not like it's going to affect SWIY much. Those things are supposed to be very durable... SWIM have used even 1lb+ of NaOH with no noticeable change in the jug.

On a lighter note, maybe its trying to self-replicate. :)
Are you sure it's not LDPE?

Also, did it ever get heated too much? HDPE has great chemical resistance at room temperature, but not when hot.
It was a #2 HDPE bottle of wiper fluid. It never got hot, if anything it was colder than room temp It was on its side most of the time.
Adding lye to water creates quite a bit of heat and a STB tek calls for A LOT of lye, that equates to a lot of heat. I've had jugs change shape from the heat before. Never from round to square, but you should be fine. I don't think it will affect your experiement at all.
yea, i've seen some crazy melting plastic too, but from the heat of the NaOH dissolving rather than any reaction.

But, round to square? as somone said, its against entropy, unless it was sitting with other things around it to allow it to go into that shape?
You probly absorbed some spice subcutaneously somehow or something. Wait until it wears off and see if the jug goes back to being round again.
He he... but seriously, that's weird. Got any pics?
Sorry no pics, it's been thrown out, it was getting even more square. It really didn't get very hot and if the deformation was caused by heat i would expect it to be instantaneous. This happened over night, it was sitting on it's side and it was rolled around periodically. If it happens again I'll get the dude to take pics
I think I know what he's talking about...

Did the pressure inside simply decrease while the cap was sealed? I've seen the round HDPE containers have the sides sucked in when pressure inside drops, and if it happens on all four sides it looks like a rounded-square type shape. I doubt the plastic melted and reformed or anything...
heh this happened to swim the other day

swim said it since added more vinegar soak to the base/naptha solution mayhaps neutralizing it somewhat swim didnt check ph however he noticed the bottle went back to round..... odd eh? done several naptha pulls from said bottle... it seems to be whats desired swim has no fear of shape shifting bottles they cant fool him


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