The WAXS technique is used to determine the degree of crystallinity of polymer samples.3 It can also be used to determine the chemical composition or phase composition of a film, the texture of a film (preferred alignment of crystallites), the crystallite size and presence of film stress. As with other diffraction methods, the sample is scanned in a wide-angle X-ray goniometer, and the scattering intensity is plotted as a function of the 2θ angle.
X-ray diffraction is a non destructive method of characterization of solid materials. When X-rays are directed at solids they scatter in predictable patterns based on the internal structure of the solid. A crystalline solid consists of regularly spaced atoms (electrons) that can be described by imaginary planes. The distance between these planes is called the d-spacing.
The intensity of the d-space pattern is directly proportional to the number of electrons (atoms) in the imaginary planes. Every crystalline solid has a unique pattern of d-spacings (known as the powder pattern), which is a fingerprint for that solid. Solids with the same chemical composition but different phases can be identified by their pattern of d-spacings.
Podorov, S. G.; Faleev, N. N.; Pavlov, K. M.; Paganin, D. M.; Stepanov, S. A.; Förster, E. (2006-09-12). "A new approach to wide-angle dynamical X-ray diffraction by deformed crystals". Journal of Applied Crystallography. 39 (5). International Union of Crystallography (IUCr): 652–655. doi:10.1107/s0021889806025696. ISSN 0021-8898. /wiki/Doi_(identifier) ↩
"WIDE-ANGLE X-RAY DIFFRACTION THEORY VERSUS CLASSICAL DYNAMICAL THEORY" by S.G. Podorov, A. Nazarkin, Recent Res. Devel. Optics, 7 (2009) ISBN 978-81-308-0370-8 /wiki/ISBN_(identifier) ↩
Murthy, N. S.; Minor, H. (1990-06-01). "General procedure for evaluating amorphous scattering and crystallinity from X-ray diffraction scans of semicrystalline polymers". Polymer. 31 (6): 996–1002. doi:10.1016/0032-3861(90)90243-R. ISSN 0032-3861. /wiki/Doi_(identifier) ↩