Date of Award


Degree Name

Bachelor of Science


Pulp and Paper Technology


The inability of fibers to swell to their original extent is probably the largest single factor contributing to strength losses of repulped fibers. This lack of swelling lessens the number and strength of fiber to fiber bonds in the sheet formed. It is this fact which leads to the decreased mullen, tensile and stretch of the sheet, and the increased tearing resistance. This paper is a study of the effects of temperature, pH and surfactants on the strength properties of secondary fibers. It was shown that a surfactant is very detrimental to strength properties. While not affecting some strength properties, pH affects mullen and fold strength, with a low pH giving a higher mullen and fold. The effect of temperature is less, affecting only the fold resistance. It is quite possible that other strength properties are affected by temperature and pH, but these differences, if present, are small and could not be detected by this experiment.