Re: Where can I find information on what makes a waterballoon fireproof?

The secret is in the water. Water is a very good absorber of heat, and 
carries the heat of the flame away from the rubber skin of the balloon 
before it has a chance to raise it to its melting point. Native people used 
this same idea to boil water in skin bags, and it's still a popular bonfire 
trick to put a paper cup full of water on a fire and amaze everyone that it 
doesn't burn.