Chemical Forums
Specialty Chemistry Forums => Materials and Nanochemistry forum => Topic started by: tone999 on August 06, 2009, 09:26:41 AM
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Q. Write the chemical formulae for polyethylene, polyproplylene, PVC and polystyrene and on the basis of their chemical features describe why they exhibit different glass-transition temperatures.
A. Polyethylene = (CH2)n
Polyproplylene = (C3 H6)n
PVC = (C2 H3 Cl)n
Polystyrene = (C8 H8)n
That bit is fine i think?
But why they exhibit different glass-transition temperatures?
Is this because of the different groups eg. aliphatic, side groups, polar groups etc.
Any help would be much appreciated
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I'd draw out the structures more clearly then think about what the structures mean in terms of packing amd movement of the different polymer chains.