Is´t possible to see the peak of mixing of two amorphous phases in DTA? For example, i know that we can see an exothermic peak of transition of amorphous to crystalline phase and subsequent melting (endothermic peak) of the formed crystalline phase.
For crystalline peaks, deconvulation can be done to isolate the peak. But for amorphous polymers, there will be only base line shifting. Two amorphous polymers can be compatible, semicompatible or non compatible. Except the first case the different Tg base line shifting can be located. If not, run the DSC with low heating rate (preferably) or expand the curve at temperature of interest.
Many many thanks for your response Asit Baran Samui. Yes is true that in case of two amorphous phases, if the composition is different we can observe two Tg(s) for both. However, i have a situation whereby one glass composition phase separate into two amorphous phases by spinodal decomposition. Note that the glass phase separate upon heating at temperatures above Tg (lower critical temp) and thereafter i observe an endothermic peak just near the upper critical temperarure (mixing of phases occur to form again single phase) of this glass. There was no crystalline peak and i observed only one Tg. Now my worry is that, i have never seen any literature refereing to such an endotherm as mixing of two amorphous phases, is mostly associated with melting of the material or melting of crystals. Do you think we can obsereve such an endotherm due to mixing of two amorphous phases?
Yet, it is possible, check my article 10.1016/j.jnoncrysol.2019.119849
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