The pressure isn't the problem. The vacuum is. Hard vacuum (10^-6 torr or greater) causes materials to outgas. This means the material weight is literally reduced by the vacuum. The seals of the zipper assembly are are elastomers, which are especially susceptible to outgassing.
You're not getting it.
The pressure isn't the problem. The vacuum is. Hard vacuum (10^-6 torr or greater) causes materials to outgas. This means the material weight is literally reduced by the vacuum. The seals of the zipper assembly are are elastomers, which are especially susceptible to outgassing.
There's a whole field of materials science related to using this to create thin coatings.
It's not just going underwater in reverse. The hard vacuum of space is a uniquely hostile environment to man-made materials.
Thanks for your opinion.
Now demonstrate that these zippers cannot withstand a vacuum.