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A new technique for measuring the water content of fiber is presented. Tritiated water is added to a pulp/water suspension whereupon the tritium partitions between the bulk water and the pulp. Through this technique a fiber:water partition coefficient is developed, Kpw. This thesis will cover the development of the Kpw procedure and three different case studies. The first study involves comparing Kpw to traditional methods of fiber water content. The procedure provides a value of ten percent for the tightly bound water content of unrefined hardwood or softwood kraft fiber, either bleached or unbleached. If this water is assumed to cover the fiber surface as a monolayer, then an estimate of the wet surface area of fiber can be obtained. This estimate compares well to independent measurements of surface area. Kpw has also been found to be valuable in furthering the understanding of refining. Based on the study, it is proposed that refining occurs in three discrete stages. First, refining removes the primary cell wall and S1 layer while beginning to swell the S2 layer. Next, internal delamination occurs within the S2 layer. Finally, fiber destruction occurs at high refining levels. By using Kpw, the three stages of refining are clearly recognized. Lastly, Kpw is used to study the effect of hornification on bleached softwood kraft fiber. The recycling effects at three refining levels were characterized by Kpw and followed closely the findings of the refining study. At low and high refining levels, the impact of recycling was minimal according to Kpw results, but at 400 mL csf the impact of recycling was much more pronounced. This could be attributed to the closing of internal delaminations within the fiber.

Non-ionic copolymers, such as poly(1-vinylpyrrolidone-co-styrene), are used in the production of filtration membranes and fibers because of their ability to provide both hydrophilic and hydrophobic character. However, their non-ionic character and solubility in water prevents inexpensive recovery from waste streams. Wood fibers show potential as recovery agents because they are inexpensive, environmentally friendly, and have a large surface area per unit mass (200 m2/g). However, due to the anionic nature of the fiber surface, their adsorptive behavior is often limited to cationic species. We have shown that low-dosage application of a cationic polyamide epichlorohydrin resin, Kymene 557H®, using a sequential adsorption process can alter the fiber surface charge so as to provide more neutral surface area for the non-ionic polymer to adsorb; furthermore, the adsorbed Kymene 557H® does not block the approach of poly(1-vinylpyrrolidone-co-styrene). Single-component adsorption of poly(1-vinylpyrrolidone-co-styrene) was on the order of 10-3 g/g; with Kymene 557H® adsorbed on the fiber, the adsorption increased one order of magnitude to 10-2 g/g. This significant increase is caused by neutralization of fiber surface charge via Kymene 557H® adsorption, creating a surface more favorable for adsorption and recovery of non-ionic species.

Thesis (Ph. D.)--Institute of Paper Chemistry, 1942. / Includes bibliographical references (p. 106-107).

Thesis (Ph. D.)--Institute of Paper Chemistry, 1949. / Includes bibliographical references (p. 118-120).

Thesis (Ph. D.)--Institute of Paper Chemistry, 1940. / Includes bibliographical references (p. 87-88).