Can a bag be considered the container for an Explosive Trap?
Explosive Trap
Explosive traps are the standard, bread-and-butter of traps. They cause large amounts of physical damage to any creature in their radius. Explosive traps can do from 4 to 60 points of damage. Explosive traps cannot be resisted by anything short of Ritual Magic or Racial Abilities. Each Trap Raw Material used in the creation of an explosive trap grants the trap 4 points of damage. Explosive trap containers must be at least 10 cubic inches for each point of damage the trap does. So a 4 point explosive trap must be at least 40 cubic inches (or 8”x5”x1”) but a 60 point explosive trap would be 600 cubic inches (12”x10”x5”). Explosive traps are Area of Effect and damage everyone within 5 feet from the center of the container. Explosive traps and triggers are destroyed upon detonation.
I don't see why not - but it will still need to meet the volume requirements, so it can't just be a bag that could hold that volume. It must remain at least that volume in expansion.