For "sudden":
* rupt- (to break, burst): Think "rupture", "eruption"
* ex- (out of, from): Implies a sudden outward motion
* subit- (sudden): More about unexpectedness than force
* impet- (to attack, drive forward): Suggests a forceful, sudden action
For "burst" and "material":
* erupt- (to burst forth): Good for a volcanic eruption, or a sudden outpouring
* fund- (bottom, foundation): Could be used for a sudden release from a reservoir
* effus- (to pour out): Conveys a pouring out of something, but not necessarily sudden
* -ium (noun ending): Can be used to denote a substance or material
Possible combinations:
* ex-rupt-: A sudden bursting outwards (think "explosion")
* subit-fund-: A sudden release from a foundation (think "dam break")
* erupt-ium: A substance that bursts forth (think "lava")
Ultimately, the best Latin root for your purpose will depend on the specific context and the exact meaning you want to convey.
For example, if you're describing a sudden release of gas, "ex-rupt-ium" might be a good choice. But if you're talking about a sudden surge of creative ideas, "impet-fund-ium" might be more appropriate.