What happens when PVA glue sets? I am curious about the white PVA glue that is commonly used for bonding wood and paper. Although an Internet search find lots of articles they mostly seem to be near copies of one another and not even the Wikipedia article say much about the curing process.
As far as I could discover, the glue is an emulsion of the PVA polymer in water which sets as the water is drawn away into the materials being bonded, and ultimately evaporates, however, if there is no chemical change in the PVA then I would expect that this would be reversed by supplying enough water.
If it does change chemically then is there something in the environment that promotes the change?
Also, does the glue ever bond chemically to the materials being joined? If so then what types of material will it bond to, and if not then, presumably, it will only give a good bond between porous materials.