Can I Use A Glue Adhesive On Cardboard 2x2's?

I experimented once, using archive-safe acid-free glue tape on a 2x2. Held it down for a couple days with clamps to make sure the glue set. Came apart after about a month.

I use self-adhesives personally. Certain brands do run the risk of discoloring bronze or brass coins, like Canadian dollars, so keep that in mind. Other brands use flimsier plastic and are prone to tearing. I've tried out different brands and settled on one I trust. If you buy them in bulk they don't cost so much.

Self-adhesives look cleaner, they're easier to label, and on the whole more presentable.

Yes I have to use ebay because the nearest coin shop is in Perth 5 hours away.
I don't think that they are too expensive and the are realy easy to use.
Ive chuked all my plastic sleeve rubbish away.
You can get nice boxes to store these in as well

Basically as already noted if you try to glue a 2x2 flip you would be attempting to glue the maylar, or plastic, to another of the same type. Some glues work on that and some don't. Usually the glues that do work on plastics are the ones made for model building. Those basically work on the principle of sort of melting the plastics together. Similar to the PVC glue for piping.
The really scarry downside of gluing a 2x2 shut is glues all emit gasses as they dry. Watch as any glue, rubber cement, Silicon sealant, etc. drys and note the odor. That is the gasses emitted during curring. It is also what would attack your coins.
Summation is don't use glue to close a 2x2.

on wizard coin supply, Self Adhesive 2x2 Holders -- 20mm (Cents/Dimes) are 50 for $8.21

I don't use self adhesive 2x2's, so another person needs to comment.