[DarekN]

Hello,

Is it possible to manufacture (or buy) a liquid that has negative coefficient of thermal expansion (expands while cooled) ?

Thanks,
Darek

[Arkcon]

Yes.  Much of the planet Earth contains water, which is available at a reasonable price in most areas.  Water expands between the temperature of 3.98 °C down until 0 °C, when it freezes. https://en.wikipedia.org/wiki/Water#States

I'm going to assume you already knew about water.  But I bring it up because you didn't trouble yourself to mention: how much expansion, and over what temperature range do you mean.  The alloy called Wood's metal also expands when cooled.  And a number of other composite solids as well.  https://en.wikipedia.org/wiki/Negative_thermal_expansion#Materials

If water and these materials aren't what you're looking for, you have to tell us why.

[DarekN]

I am interested to have a "container" with water mixed with this negative thermal expansion liquid (in right proportions) to obtain a mix that has 0 thermal expansion coefficient (and still be a liquid). I would like to have it in "room temperature / conditions".

Is now everything okay?

[billnotgatez]

@DarekN
What did your GOOGLE search turn up for

zero thermal expansion liquid

[Enthalpy]

If you have such a solid, you can make a suspension of it in a liquid. Maybe the suspension fulfils your wishes?

And what if the expansion of the container matches that of the liquid? Solid polymers tend to expand much.