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The aluminum anti-seize (Permatex) that I have had for several years has suctioned the bottle (Sides bending in a lot). I haven't used it for over a year so I don't know when or how fast this happened.

Does anyone know why this happens and if the anti-seize is still good?

UPDATE: Reached out to Permatex and got the following response. They didn't know what caused the shrinkage, but did state that it has a "3 year shelf life" and that "If the product is still has good consistency then it is okay to use, if it has stiffened up, try adding a little mineral oil to it." I am going to continue to use what I have since mine still seems to have the same consistency.

Pᴀᴜʟsᴛᴇʀ2
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FreakyDan
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1 Answers1

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I'm no chemist, but the safety data sheet suggests the presence of 10-30 % calcium oxide by weight.

Calcium oxide appears to be hygroscopic, so just like old brake fluid in a bottle it absorbs moisture from the air present inside the container and creates a small suction effect.

I can't comment on the efficacy of old anti-seize, but it will likely depend on the role that the calcium oxide plays.

Zaid
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