Actually it's not really a food item, but I have a plastic (Rubbermaid)
livestock tank that has a hole in it from the tank heater melting thru
it. I'm thinking about using a piece of tin, putting 100% pure silicone
on the tin, and bolting it thru the plastic. But is silicone safe for
this sort of use? I dont want to make my horses sick.

Or, has anyone used something else for this type of repair? I was
wondering about using fiberglass autobody matting and the fiberglass
liquid, but question if that will adhere to the plastic. I'm not sure
what type of plastic is used on these tanks, and not sure how to find
out.

Another thought is gluing the tin on with JB-Weld, but again, will it
adhere to the plastic?

Then too, is fiberglass and JB-Weld safe on food items?

I was looking for the MSDS sheets for silicone, but google has 3.6
million possibilities and seems to refer to OSHA, but they dont seem to
have the sheets on their HUGE website that would take days to hunt thru
all of it. Then there's http://www.msdsonline.com, which wants us to
pay $499.00 for the data. Screw that! This should be free to the
public.
I'm at a loss where to find these sheets online.