WAXS - XRD, calculating the degree of crystalinity

[Sancho Panza]

Homework Statement

Hello, I have done WAXS measurement on 3 samples of PP(Polypropylene). These samples are from plates processed by hydraulic pressing, it is the exact same material and the only difference is in postprocessing.
1st. Was immediately cooled in water
2 nd. Was put into another hydraulic press for 5 hrs at 80 °C
3 rd. Was put into dryer for 24 hrs at 140°C
This should lead to the different degrees of crystalinity, which is to be examined from measured data.
I have used program "PeakFit" to analyze, first i subtracted baseline and then created another baseline on 2nd derivation, (1st was linear) and substracted it also. After each subtraction area under curve changed, i used this to calculate degree of crystalinity with equation:

X% crystalinity = (area of peaks / whole area)*100
[area of peaks = area after 2nd baseline subtraction; whole area = area after 1st linear baseline substraction]
I determined that the angle from 7° to 30° is relevant for my calculation

This is graph showing measured data:

Blue is water
Balck is hydraulic press
Red is dryer
Number behind X is crystalinity i have caculated.

I will also upload *.ASC data files, because my question is "Have I done this right, can someone check after me?" I have a feeling that I have missed something.

I know this can be also calculated in Origin, but i am completely lost in that program ( so far i can only make graphs in it ) so if someone would be kind enough to explain to me the calculation in it i would be thankful.

Homework Equations

The Attempt at a Solution

 

[Valkarie]

I believe you've calculated the crystalinity correctly. In Origin, you can calculate the crystalinity in a few ways. My preferred approach would be to use the Fit Peaks function (under the Fitting menu) to determine the areas of each peak. You could also just measure the area directly by selecting the data points (using the Data Cursor tool under the Tools menu) and using the Statistics tool (under the Analysis menu) to measure the area.Once you have the areas of each peak, you can then calculate the percentage crystalinity as you have done before.