Dear All,
I added different amounts of nanoclay (e.g. wt% 1,3,5) in my polymer matrix. I couldn't observe any peaks related with my filler especially for 1 and 3 wt%. I tried to change slits, scan speed etc. and none of the parameters worked.
Operating conditions are; 45 kV 40 mA.
Any help will be appreciated.
Regards.
Yusuf Kahraman sir,
generally unmixed intercalated and exfoliated confirmed by XRD.
no peaks are observed for Exfoliated system.
@bhaskar you are right but in my case It is more likely to observe a shift in peaks position. It s unlikely to have exfoliation for most of the cases.
@ 5% wt sometimes is too much to achieve fully exfoliated system, However could be accrue depending on your preparation system: what you can do now is : 1- do the XRD again with different sample of 5% ( 2 or 3 samples from 5% sample) some times your clay platelets is moved only to one side of your samples, so your sample that you characterized by XRD has no any clay platelets.
2- you should do TEM to see your clay particles position inside your polymer matrix
3- you could play with Y and X scale when you draw your data
@Nagi I definetely need to take TEM images. XRD is also useful for interlayer distance. I thought that it might be related with operating conditions or decive equipments like slit size,mask number etc.
Generally, the lower wt% of clay particles in the polymer matrix provide good dispersion and lead to exfoliated structure. Absence of peak at small angles shows that the inter-layer distance between clay particles is more than 75 um.
To confirm the above argument, Small angle X-ray scattering (SAXS) and Transmission Electron Microscopy (TEM) techniques could be done for getting more insights.
The characteristic X-ray diffraction peak of the nanoclay cannot be seen in samples due to the exfoliation of the nanoclay in these vulcanizates.
I have added Cloisite 15A into epoxy by mechanical stirring in the range of 2.5 to 4.5 wt%. There were no sharp peaks observed in the range of 6o - 30o
AS OTHER COLLEGUES INDICATE AN EXPHOLIATION PROCESS MAY BE OCCURS, BUT ALSO ON DEPEND THE DIFFRATION RANGE OF MEASUREMENT, IF YOU MADE THE ANALYSIS AT SMALL ANGLES OR WIDE ANGLE, SOME MODIFIED CLOISITES PRESENT PEAKS UNDER 5 DEGREES, SO THAT COULD BE THE ANSWER
Je pense que le mélange de la nanocharge avec une matrice polymère a complètement détruit la sructure cristalline initialement presente dans la nanocharge. Ceci peut s'expliquer par une structure exfoliée du nanocomposite formé.
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