Hello. As you can see, I'm new here. I have a little experience in physics and I've taken through Calc 2 in college. I'm trying to build a portable air conditioning unit. My current design consists of a tub of water with a 6" cube-shaped container of some kind submerged in it containing dry ice, then pumping the water through a used heater core and using a fan to move air from around the core. My problem is what material to use for the container for the dry ice - I need to pick one with the highest possible thermal conductivity without allowing the water to freeze. (Also it has to be one I can buy online or in a store for relatively cheap and manipulate easily) I don't know how to manipulate thermal conductivity data to determine which material will work best here. Any help would be greatly appreciated.