The superstructure of melt‐crystallized polyethylene. I. Screwlike orientation of unit cell in polyethylene spherulites with periodic extinction rings

摘要: The ringed structure in polyethylene spherulites was investigated by an x-ray microdiffraction method. A spherulite with extinction rings whose interval is about 50 μ observed when viewed under the polarization microscope. An asymmetric diffraction fibrous pattern b axis obtained for this specimen. This indicates that area of (several microns diameter) unit cells are never randomly oriented around a common but have nearly similar orientations. series micro-diffraction patterns at intervals 13 (about 1/4 fringe interval), and it shown screwlike orientations their along radius. distance corresponding to one-half pitch screw just accordance ring interval.