I've noticed that some organic chemicals are sold in HDPE containers despite compatibility charts indicating that such containers are not appropriate acetone.

Compatibility Chart

Acetone Listing

For example, this acetone listing from Walmart above uses an HDPE container, but when incompatible solvents are packaged in HDPE containers the containers can experience a relaxation in the polymer stress from blow molding causing the bottle to contract as shown below.

Shrunck Bottles

How can they use incompatible containers and still safely package solvent products?

  • $\begingroup$ This will never lead to the bottle or cannister breaking. Also I strongly suspect you only see the effect so clearly because the cannisters were half empty and temperature changes made the outside air pressure compress them. Also empty PE bottles deform permanently in this case. $\endgroup$ – Karl Aug 22 '18 at 5:48
  • $\begingroup$ @Karl, Break? Porbably not. But I have had full bottles of oleic acid and PEG 400 panel. Oleic acid will even diffuse to the outside and oxidized to form a viscous grease. but paneling has little to do with atmospheric pressure. If you look, the bottle in the left most image has no head space and atomospheric pressure does not swing that drastically in a single location. You can leave bottles closed through all kinds of weather and not get anything that looks like paneling. $\endgroup$ – A.K. Aug 22 '18 at 16:26

The shrinkage is called panelling and bottles that are otherwise incompatible are made compatible by a process called fluorination. In fluorination the HDPE is exposed to fluoride gas with precise control in time, temperature and pressure. This exposure converts the outer layers of polyethylene to a highly fluorinated polymer similar to teflon.

$$\ce{-(C2H2)_n-~+ 4 F2~~ \longrightarrow ~~-(C2F4)_n-~ + 4HF}$$

This fluoropolymer coating greatly reduces diffusion of the solvent into the plastic and thus the solvent is unable to soften the plastic, preventing paneling.


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