Nordic Pulp Paper Research Journal Issn Is Man Responsible For Climate Change Essay
The fiber surfaces, consisting of cellulose, hemicelluloses and lignin in varying compositions, form stable bonds thus creating a composite material with remarkable strength per square meter.
The water is removed through the mesh and the remaining fiber mat is pressed and dried.Interdiffusion refers to the migration of these molecules, usually polymers, from one fiber into the other.Interdiffusion is believed to be a key mechanism of fiber-fiber bonding.The fibers in paper bond to each other by six different mechanisms: interdiffusion, mechanical interlocking, capillary forces, Coulomb forces, hydrogen bonding and Van der Waals forces.Reviews on fiber-fiber bonding and its mechanisms are given by numerous authors. paper, depends on the strength of these component fibers and the strength of the bond between these fibers.Here we show the first approach to quantify the bonding energies contributed by the individual bonding mechanisms.We calculated the impact of the following mechanisms necessary for paper formation: mechanical interlocking, interdiffusion, capillary bridges, hydrogen bonding, Van der Waals forces, and Coulomb forces on the bonding energy.Contact depends on a highly deformable fiber surface in the elastic (low E-modulus) and plastic (low indentation hardness) regime.Recently, a quantitative contact mechanics model describing the development of molecular contact for soft surfaces due to capillary forces was reported we previously found that the area in molecular contact in dry paper is close to full contact (about 90% of the optically bonded area).Experimental results quantify the area in molecular contact necessary for bonding.Atomic force microscopy experiments derive the impact of mechanical interlocking. A model based on the crystal structure of cellulose leads to values for the chemical bonds.