Orientation analysis
Orientation analysis,
what is measured?
The information obtained here is the orientation of a scattering structure, such as crystalline lamellae or fiber axis with regards to a sample plane of reference (or machine direction for processed samples). Orientation parameters are extracted from the azimuthal distribution of intensities of a specific Bragg peak. In the case of a tensor approach method extracted parameters are the mean orientation angle and the degree of orientation obtained.
![Orientation analysis](https://www.xenocs.com/wp-content/uploads/2020/10/Orientation-analysis-SAXS-data.jpg.webp)
Figure 1. Azimuthal profile of the Q = 0.27 nm-1 Bragg reflection of a high density polyethylene. The mean orientation is found at 39.9° for a rate of 17% oriented scatterers.
Alternatively, Herman’s orientation factor, which is a moment of the complete orientation distribution function, can be calculated to access the orientation of the scattering plane.
Samples
Typical samples for this measurement are:
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Textured materials
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Nanostructured materials
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Semi-crystalline polymers
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Fibers
Methods & standards
Standards & methods used for tensor approach:
- David K. Cinader, Wesley R. Burghardt, “X-ray scattering studies of orientation in channel flows of a lyotropic liquid crystalline polymer”, Polymer, Volume 40, Issue 15, 1999, p. 4169-4180
Standards & methods used for Herman’s Orientation Factor:
- J.J. Hermans, P.H. Hermans, D. Vermaas, A. Weidinger, Quantitative evaluation of orientation in cellulose fibers from the X-ray fiber diagram, Recl. Trav. Chim. Pays- Bas 65 (1946) 427–447.
XSACT analysis software implements the above methods.
![SAXS Data Analysis](https://www.xenocs.com/wp-content/uploads/2019/02/Xenocs-XSACT-Laptop.png)
Why use SAXS or WAXS for nanostructure or molecular orientation analyses ?
Advantages of SAXS or WAXS for nanostructure or molecular orientation analyses:
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SAXS or WAXS are non-invasive measurements
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SAXS or WAXS can measure in opaque sample environments or probe all the volume within the X-ray beam
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One can conduct dynamic studies in order to probe changes in orientation (direction and degree) induced by temperature and strain
![](https://www.xenocs.com/wp-content/uploads/2022/07/Saxs-application-overview-scaled.jpg.webp)
Products
All these measurements are possible directly in your lab.
Xeuss Pro
The Ultimate Solution for Nanoscale Characterization using SAXS/WAXS/GISAXS/USAXS/Imaging
![Xeuss Pro The Ultimate Laboratory SAXS/WAXS/GISAXS/USAXS Beamline](https://www.xenocs.com/wp-content/uploads/2024/06/Xeuss-pro-vBigger.jpg)