I don't have that brand of cooler. But here is my $0.02, based on the following information from http://www.igloocoolers.com/FAQs
"Hard-side coolers: The exterior body of most Igloo hard-side coolers is made of high-density polyethylene, while the interior liner is made of FDA-grade polypropylene. The insulation is made of Ultratherm™ - a proprietary blend of polyurethane foam."
Polypropylene is good to 160 oC and is what my electric kettle is made of, the one that I bought from the hardware shop to boil water for tea.
HDPE is good to 130 oC. I have a 60 litre HDPE barrel that I have used to cook grain by steam injection at 95-100 oC for 2-3 hours with no ill effects. It is supposed to soften slightly at this temperature range but I have not noticed any warping or other problems.
The temperature range of polyurethane foam depends on its application (it is commonly used as a fire retardant) but it is good to 250 oF (120 oC) according to http://www.engineeringtoolbox.com/in...res-d_922.html
I suspect some of the problems people are reporting come from having used coolers with polystyrene insulation which melts at 100 oC.