The most critical factors affecting runnability of paper machines are the tension and relaxation properties of wet paper. In this study, the effect of electrolytes, pH and surface tension on dry and wet web properties was investigated. Addition of a non-ionic surfactant at pH 6.5 and conductivity level of 1 mS/cm, achieved by addition of CaCl2, decreased surface tension and increased dry content. Density, air permeability and tensile strength increased for dry sheets. Tensile strength and residual tension at 2% strain of the wet web increased until a concentration of 0.25 g of surfactant/L of water, primarily due to the increased dry content. Lowering of pH from 6.5 to 5, decreased dry content after wet pressing and air permeability of dry sheets. Adjustment of conductivity with NaCl caused a decrease in both tensile strength and residual tension for wet sheets.
|Number of pages||7|
|Journal||Journal of Pulp and Paper Science|
|Publication status||Published - 2009|
|MoE publication type||A1 Journal article-refereed|