Hey there!
POLYCARBONATE SHEET (http://www.polymerplastics.com/transparents_lexan.shtml)? Do you know about it? For your information, this Polycarbonate sheet is useful as bullet resistant. It’s also good for weather ability; Thermoform ability and UV resisting. Perfect for security; signage; guards; shelter and skylight. I am sure there are others same product out there. If you found one you may reply me.