Reply To: Staining & Gluing

The chemistry of PVA glues are a bit more complex than just dissipating water. The poly Vinyl Acetate is an emulsion in water, which greatly slows down its ability to polymerize, or form long acetate strands. When water leaves, the chemistry of the glue is different, and not readily reversible. And for this reason PVA doesn’t adhere well to dry PVA, and it’s fairly resistant to water, oil, or greases.

Hide and animal glues are mostly reversible, but PVA and it’s ilk can’t be readily reversed.

It’s also why PVA has a shelf life. Even when mixed with water in the sealed tube, the glue will eventually form long stringy molecular chains.