Calculation of % crystallinity of composite polymer from DSC curve
Sophia Leimapokpam . You need to calculate the area under the melting temperature peak. and then use the following formula:
Xc(%) =[Delta Hm/ ((1-w) * Hm)] x 100
Delta Hm = area under Tm peak
w = weight fraction of component (like any fillers or modifiers, if any)
Hm = meting enthalpy at 100% crystallinity (from literature)
Hope this helps!
Dear Sophia,
The degree of crystallinity (Xc) can be calculated based on following equation
where DHm, DHcc, and W are the enthalpy of melting, enthalpy of cold crystallization, and the weight fraction of polymer in sample (maybe it is 100% or less than 100% if blend of polymers has been used in samples) respectively. DH0f is the enthalpy of fusion of complete crystalline polymer that can be find in handbook.
Xc(%)= (DHm-DHcc)*100 /(W* DH0)
DSC produces a heat flow (W/g or mcal/sec) vs temperature (K or Celsius) curve, see attached example.
Degree of crystallinity = ((Delta Hf - Delta Hc)/Delta Hf,100%) x 100%
where Delta Hf is the enthalpy of melting, Delta Hc is the enthalpy of crystallization, and Delta Hf,100% is the enthalpy of melting for a fully crystalline polymer which you will need to look up. Enthalpy is the area under each peak so to get enthalpy values for crystallization and melting you might be able to use a curve fitting software that comes with the DSC eqipment.
The degree of crystallinity is influenced by processing conditions and thermal history of the polymer so you need to consider your temperature ramping rates throughout the experiment which is how quickly the sample is heated and cooled.
http://pslc.ws/macrog/images/dsc08.gif
Kindly refer to these papers for the reference
https://www.scielo.br/j/mr/a/MYFx5qgLqnQVKKh5Wt54bJB/?lang=en
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