Cryofracturation can show phases in polymers compound if they have a contrast in mechanical properties, even in presence of compatibilizer. If they have the same mechanical behavior, you can try to solubilise one of the phase, i did it for sample of epoxy with polystyrene inclusions. High quality cryogénique cutting can even reveal crystallite morphology. If it's not enough, it exist some methods to engraft heavy atoms on specific molecular function, like osmium tetroxyde in order to see them as a white pattern in backscattered electron mode.

Dear Chandan,

FESEM images are usualy used for morphological studies.Example to relate the following things in a polymer composite:-

a) Attachment of filler and matrix

b) Ductile of brittle behavior of the composite

c) Agglomeration presence( if poor results was indicated)

FESEM will not revile much info on nano particles, such as exfolialtion or Intercalation, you may try TEM ....for beter finding. Pls feel free to email me if u need and assistance. Good luck.....