Plasmating
this was a process developed by the Trade Federation, during the last decades of the Old Republic, in which materials were created in such a way that they were reduced to their constituent atoms when damaged. In this way, special diplomatic packages and delivery vessels could be formed to open only with the proper identification - keycodes, biometrics, etc. - and if the package was ruptured or forced open, the contents would plasmate, rendering them useless.