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Can someone reformulate an instant ice pack to be colder?

  1. Apr 1, 2016 #1
    I'm working on a new invention that requires a disposable instant ice pack using ammonium nitrate and water. I need the temperature of this new ice pack to get within the range of -15 deg F
    I have tried using larger quantities of ammonium nitrate but was only able to lower the temperature 6-8 degrees colder...nothing significant. Current disposable ice pack reach 30-40 deg F and are required by the EPA to maintain this temp for 20 minutes to qualify as an ice pack. Mine would only need to stay cold for a 2-3 minutes.

    I've read that most instant ice packs typically use less than 28% nitrogen in its formulation. Maybe increasing the nitrogen content would work?
  2. jcsd
  3. Apr 1, 2016 #2
    You want a more strongly endothermic reaction.

    Components in consumer ice packs are chosen for their safety and cost as well as their temperature properties.

    If you are not limited by safety or cost, you should consider other materials.

    Do some searches for most effective endothermic reactions.
  4. Apr 1, 2016 #3
    Thanks Dr. Courtney for your insight. Yes I need a stronger endothermic reaction. I was hoping to reformulate ammonium nitrate as it is safe for consumers (sealed in a thick poly bag) and a low cost material but I will look into other materials as well.
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