Polystyrene and Ether

Name: Anjil
Status: student
Grade: other
Location: ID

Question: When polystyrene is dissolved in ether, it shrinks but does not 
dissolve. Can you please tell me why this happens?
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The Polystyrene does in fact dissolve.

What is more important in the spectacular nature of the activity is that the 
dissolved polystyrene allows the gas to escape from the bubbles that make up 
the Polystyrene Foam, which is what you are usually dissolving - that is why it 
shrinks.
As the ether evaporates, the styrene is recovered from solution, but without the 
bubbles. It becomes a firm, rigid plastic - exactly the same stuff that plastic 
model aircraft is made from.
I have a friend who uses polystyrene foam to create model landscapes for train 
sets and 'Dungeons and Dragons' by carefully painting acetone to dissolve away 
portions of the foam to create mountain slopes and river channels. etc.

Nigel Skelton
Tennant Creek Australia
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