The flatness of lignosulfonate macromolecules as demonstrated by electron microscopy



A high molecular weight lignosulfonate was examined in the electron microscope using three different methods of preparation. In all cases, the lignosulfonate macromolecules appeared on the photomicrographs as spots about 10 nm in diameter. From the molecular weight and the diameter of the spots, it was deduced that the lignosulfonate macromolecules were irregularly shaped disks lying flat on the carbon film with an average thickness of about 2 nm. This conformation was consistent with the lamellar structure previously proposed for the cell wall of wood.