Measurement of orientation in uniaxially drawn polyacrylonitrile

In the literature, an estimate of the degree of orientation in drawn polyacrylonitrile (PAN) fibers is often inferred from the arc‐width of the strongest equatorial peak at 2ϑ = 16.8° in the wide angle X‐ray diffraction pattern. The absence of sharp meridional peaks in the diffraction pattern of oriented PAN means that chain orientation‐factors cannot be directly calculated. In this work, Wilchinsky's method for calculating the degree of chain orientation from the azimuthal intensity distribution of a strong equatorial peak has been adopted.