Wet Paint in Space - Scientific Discussion

[Electroman]

It makes me wonder, does paint dry in vacuum?

 

[GoTslaGo]

It makes me wonder, does paint dry in vacuum?

I think you need to propose that question to NASA, so they can set up an experiment for the next trip up to ISS. I think it’s a good question.

 

[macpacheco]

It makes me wonder, does paint dry in vacuum?

I don't think its a necessary experiment.
There are vacuum pumps that create a vacuum environment.
Chemical reactions that take place when paint dries are well known, and the effects of a vacuum on it are fairly easy for a chemist to predict.

My very basic chemistry knowledge suggests:
A vacuum should dry the paint faster, if the actual process is actually "drying", aka, loosing H2O or some other volatile chemical that evaporates. Vacuum is the lowest pressure state possible, accelerating the drying process.
For instance when aircraft accumulates frost, the higher the altitude, the faster the frost sublimates, as H2O wants to become a vapour and fill out the vacuum.

 

[jkn]

Liquids do not exists in vacuum. Not even for a short moment. Paint would explode into gas and solid.

Predicting next question: Human skin is strong enough to prevent blood from boiling.

 

[mongo]

Liquids do not exists in vacuum. Not even for a short moment. Paint would explode into gas and solid.

Predicting next question: Human skin is strong enough to prevent blood from boiling.

Mercury above ~225 K? Iron above 2000K? Are we talking space or a perfect vacuum?

 

[jkn]

Mercury above ~225 K? Iron above 2000K? Are we talking space or a perfect vacuum?

In perfect vacuum liquids do not exist. When temperature increases in vacuum solid sublimate directly into gas.
Triple point - Wikipedia
Phase diagram: Liquid does not exist when pressure is below triple point.

 

[mongo]

In perfect vacuum liquids do not exist. When temperature increases in vacuum solid sublimate directly into gas.
Triple point - Wikipedia
Phase diagram: Liquid does not exist when pressure is below triple point.

Yah, you are right, I picked up those temperatures from the phase diagrams, but they were not focused on the hard vacuum side. Triple point for Mercury is 234.3156 K, 1.65×10−7 kPa, which is three to four orders of magnitude above low earth orbit at 1-70×10-8 Pa.

 

[Ben W]

I think goal is land, quick check, refuel, fly again. No time to wait for paint to dry.

Transsonic airflow ought to dry that paint real quick.

 

[jkn]

Transsonic airflow ought to dry that paint real quick.

It would remove all wet paint. Supersonic air will remove even dry paint if it is not good enough:
XB-70 was painted so many times for VIP visits, the thick paint eventually cracked and was eroded off bit by bit due to its supersonic testing [1200x714] • r/MilitaryPorn

 

[Ben W]

It would remove all wet paint.

Pedantically, after the fuel is loaded, wouldn't it become frozen paint?

 

[jkn]

Pedantically, after the fuel is loaded, wouldn't it become frozen paint?

Yes, if it is water based paint. It would melt while coming down, if not earlier. I don't think result would look good.