Polyurethane Plastic
Polyurethane is thermoplastic, and is usually made
into a foam form. It retards the passage of heat very
well, and is used widely today as insulation in
refrigerators and freezers. It's also used as upholstery
cushions, mattresses and pillows, and carpet pads. It's
flammable unless specially treated.
Avoid contact with flame for cushions, mattresses,
etc.