Hello mmerig, I am sure that some sort of solvent or some application of heat will weaken the bond between the two layers. Just be careful and make sure you only do one of the two at a time. If you use a solvent that is flammable and apply sufficient heat, you may reach the flashpoint of the solvent and it will self ignite without any open flame. This is what is referred to as the lower explosion limit (LEL) in the hazardous waste field.
So, if you try the solvent first and it doesn't work, rinse the solvent off with water and wait until it drys, then try the heat and see if that works. It's quite possible that you could put the whole thing in a container of water for a while (days) and it might loosen the adhesive that way.
Unfortunately, without knowing what kind of adhesive was used, it's hard to say what will or won't work. If I knew the adhesive, I could find people where I work with the information. The company I work for makes machines to bond semiconductor wafers together.
If you have a decent university in your area, you may be able to find a helpful person in the chemistry dept. that can help you do this safely. They tend to have a good supply of solvents, and they have a good collection of heating devices.
Peace,
Dave