33—preparation Techniques for Studying Voids in Cellulose Fibres From Viscose

An outstanding feature of some viscose rayon fibres is the appearance of voids in their transverse1 and longitudinal sections2. As many of these voids are of the order of 0·2 μ in diameter and smaller, it is necessary to use an electron microscope to investigate them. Two different techniques were used: ultra-thin sectioning, where embedding in methacrylate, which is not very satisfactory, was replaced by embedding in Araldite; replication, the replicas being made of thick transverse and longitudinal sections, which appear to give more information about the depth and shape of the voids than do ultra-thin sections.