'Cellulose nitrate was used to make dice from the late 1860s until the mid twentieth century, and remains stable for decades. Nitric acid is released in a process called outgassing. The dice cleave, crumble, and then implode.'
Deception, Fate & Rotten Luck by Ricky Jay and Rosamond Purcell
I have bags of the stuff in my desk (celluloid is still the king of materials for guitar picks). Not really explosive in the huge kaboom sense but burns readily if you set fire to it (how fast depends on the form, as thin fibers it was a replacement for gunpowder, called gun cotton).