A study of diffractometer line shapes in melt crystallized polyethylene

Wide angle X-ray diffraction scans of isothermally crystallized samples of polyethylene containing known levels of chain defects have been investigated. An analysis of scattering curves using a powder diffractometer is reported. The analytical deconvolution of Lorentz and Lorentz squared profiles for the PE experimental scattering curve and the standard is performed to give the pure profile for the polymer. The separate contribution of paracrystalline lattice distortions and coherently diffracting domains, in different crystallographic directions, to the broadening of the diffraction profiles is discussed in the light of the level of defects present.