Silicone vs. carbon bond
characteristics
Bond energy – kJ/mole
Bond length – angstroms (Ǻ)
Bond angle – degrees, avg.
Barrier to rotation – kJ/mole
Barrier to rotation material comparison – kJ/mole
Long bond length combined with a wide bond angle, great freedom of rotation,
and large free volume give siloxane polymers:
-
The most open, flexible structure of any polymer
-
Incredible ease of orientation for their surface-active groups
-
A lower glass transition temperature (Tg) than any other
comparable polymer
Glass transition temperature (Tg)
comparison
Activation energy for viscous flow of linear polymers, showing the
dependence on energy for viscous flow.
PE = polyethylene, PB = polybutane, PP = polypropylene, PIB = polyisobutylene,
PET = polyethyleneterapthalate, PVAc = polyvinylacetate, PS =polystyrene, and
PVC = polyvinylchloride.
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