For amorphous polymers such as polyethersulfone (PES), a relatively sharp peak can be observed at 2θ=18 degree in the XRD pattern (bellow figure) which is known as amorphous halo and represents amorphous structure of polymer.
However, the question to the fore is, why the second peak (hump) at 2θ around 45 degree is formed (bellow figure)? What can be understood from this peak?
Thanks for your attention.
Elmira, that is also part of the amorphous pattern from your material. You do not get just one peak (hump) for a phase.
I have added a very useful presentation from ICDD which may help you in your interpretation for polymer analysis by XRD.
I do not know what instrumental settings you have used, but in order to improve the quality of your data I would suggest that you use a slightly larger slit size, perhaps a larger step size and a little longer counting time - these will help to reduce the amount of noise in the pattern. Also I notice that you do not see the true low-angle background (the pattern is rising at 10 degrees). It would be better to start from a lower angle so that you see the air-scatter fall and the true baseline before the signal from your polymer.
http://www.icdd.com/resources/tutorials/pdf/How%20to%20analyze%20polymers.pdf
Elmira, that is also part of the amorphous pattern from your material. You do not get just one peak (hump) for a phase.
I have added a very useful presentation from ICDD which may help you in your interpretation for polymer analysis by XRD.
I do not know what instrumental settings you have used, but in order to improve the quality of your data I would suggest that you use a slightly larger slit size, perhaps a larger step size and a little longer counting time - these will help to reduce the amount of noise in the pattern. Also I notice that you do not see the true low-angle background (the pattern is rising at 10 degrees). It would be better to start from a lower angle so that you see the air-scatter fall and the true baseline before the signal from your polymer.
http://www.icdd.com/resources/tutorials/pdf/How%20to%20analyze%20polymers.pdf
Dear colleague Elmira Tavasoli
Have a nice time and good day
in addition to the post of professor "Ian J Slipper", Amorphous materials is a disordered or highly disordered materials so the broadening or a hump of XRD is an indication of amorphous state. the multi humps are an indication of high disorder material, according to Radial distribution function, RDF such this materials may have short or medium range order, SRO/MRO. in case of more hump the material is highly disordered and characterized by MRO.
I wish this issue is useful.
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