fundamentals - storage modulus

[Sneakers]

I am trying to better understand some fundamentals I am struggling with here, any help would be greatly appreciated...

In two phase polymers, how is phase mixing between domains indicated in a storage modulus-temperature sweep graph?

 

[Demon3]

Miscibility is often measured by DSC. A physical mixture will exhibit two distinct glass transition temperatures at the temperatures for the Tg of the separate polymers. A true molecular mixture will show one Tg, probably at a temperature inbetween the Tg of the two starting polymers.

DMTA can also be used to detect Tg and I think that is the answer to your question. In the DMTA sweep, if you see the Tg of two polymers (step drop in modulus with rising temperature for each polymer) then it's a physical mixture (drops of one polymer in the other). If you see one Tg then it's a molecular mixture.