Fibre-fibre bond strength of once-dried pulps

We used the Page equation for tensile strength to determine the contributio n of the relative bonded area and the shear bond Strength to the loss of te nsile strength of a northern softwood unbleached kraft pulp when it is drie d. We found that the primary cause of tensile strength,reduction upon dryin g was the loss of shear bond strength, with a minor reduction caused by a l oss in the bonded al ea. The results suggest that, in order to enhance the strength propel-ties of recycled pulps, more emphasis should be placed on d er eloping treatments that enhance fibre-fibre bond strength.