How long would it take for plastic to melt if you put it in boiling water?

Question: How long would it take for plastic to melt if you put it in boiling water?
- Keywords:
- Royal Society of Chemistry: Find out more about:
  
  boil
  
  melt
  
  plastic
  
  water
Asked by Bethy Boo to Elizabeth, James, Martin, Martin, Rob on 17 Mar 2015.
- James Coombs OBrien answered on 17 Mar 2015:
  
  It depends on the plastic you use.
  
  There are loads of different plastics that we use such as polyethylene (PE), polypropylene (PP), Polyvinylchloride (PVC) and loads more!
  
  If you look on the label of the plastic you are using it will tell you what plastic it is.
  
  Boiling water is at 100 degrees centigrade which isn’t hot enough to make most plastics melt as they melt above 100 degrees centigrade. So if you put plastic into boiling water nothing will happen apart from it getting really hot!
  
  There are some plastics such as polylactic acid (PLA) which melt at around 70 degrees centigrade so if you put PLA in boiling water it will deform into a weird shape.
  
  thanks for your question!
- Elizabeth Cooper answered on 18 Mar 2015:
  
  Most plastic will not melt in boiling water. The melting point of a common plastic PET (plastic drink bottles) is 260°C. You would find it hard to find a plastic that will melt at 100°C.
  
  Some plastics however will become flexible and this temperature so you will be able to mold it into a different shape.

Question: How long would it take for plastic to melt if you put it in boiling water?