Abstract
The scattering of x-rays at small angles by various rayons of high orientation was investi gated at various degrees of swelling. The occurrence of inflection points or maxima-minima in the scattering curves of these fibers at certain degrees of swelling is explained by interparticle interference in the densely packed condition. The experimental conditions necessary for a reliable determination of particle size (diameter of microcrystallites) for these fibers are derived from the results obtained, and particle sizes determined by this method are given.