Pumukli - 2-10-2018 at 09:30
Dear All,
A few days ago I was asked a strange question:
There is a museum of "modern arts" where one of my friends work and they acquired a very neat handmade backpack which was made from a used fertilizer
bag.
These bags deteriorate over time as most of us well aware of so this backpack is expected to expire maybe within years.
Obviously they want to save it for future generations so they are after some sort of conservation technique.
Do anyone know anything about the possible techs?
I pondered that the deterioration of such a polypropylene (or polyethylene?) bag can't be stopped so the best approach might be to apply a thin layer
of transparent non-deteriorating layer of something like poly-vinyl-acetate glue and let it slowly dry (to prevent miniature bubbles to appear in the
coating). This cover would eventually hold together the falling apart bag chips/scales.
Better options?
Thanks in advance!
wg48 - 2-10-2018 at 10:25
I would think sun light would be the main culprit in normal use.
So protect it from sun light and bright lights, UV in particular and stored in a controlled low humidity atmosphere.
macckone - 2-10-2018 at 20:06
UV is the worst for plastics.
Oxygen is also bad.
Cooler is always better as long as it isn't too cold.
Plastics get brittle at low temps.
So low intensity light with UV filters, oxygen scavengers in the case.
Plasticizers will evaporate to some extent and that can't be avoided.
If it is an art piece, applying a coating may help preserve it.
Any flexible coating will lose flexibility over time.
A polymer chemist may have some ideas beyond that.
Heptylene - 3-10-2018 at 11:22
I second what has been said: UV and oxygen are bad for plastics. Humidity I don't know, it could play a role for certain biodegradable plastics?
They could put the plastic bag in an hermetic transparent plastic case filled with nitrogen. The plastic could block UV light with another coating or
if dyed. I know yellow plastic is used for some clean rooms to block blue and UV light that could interfere with photolithography.