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Gewählte Doctoral Thesis:

Nora Odabas (2016): CHEMICAL MODIFICATION AND UTILIZATION OF PAPER GRADE PULP AND FRACTIONS THEREOF Chemische Modifizierung und Nutzung von Zellstoff in Papierqualität und Fraktionen daraus.
Doctoral Thesis - Abteilung für Chemie nachwachsender Rohstoffe, BOKU-Universität für Bodenkultur, pp 164. UB BOKU obvsg

Data Source: ZID Abstracts
Abstract:
Fibers based on cellulose are a starting material for many products, old and new, from writing paper to solar cells. New processes and products as well as modifications of existing ones are sought. The most important source for cellulose is wood from trees. Mechanical or chemical processes turn the wood into a pulp that is composed of fibers and fine particles (‘fines’). The pivotal topic of this thesis is the added value use of such wood pulps or fractions thereof. This thesis contains a compilation of previous research efforts on the characterization and utilization of pulp fines. The targeted utilization of fines is a potential control variable in papermaking applications in order to obtain desirable paper properties. Alternative applications for modified fines were studied. The interaction of fibers and fines with other components in a papermaking suspension or in a composite material is based on their shape, size, and chemistry, i.e. on their specific surface area and surface properties. Both fibers and fines are negatively charged by nature. This charge can be reversed by chemical modification of the cellulosic material for different applications. The ‘cationization’ is usually carried out by etherification; a popular agent used also in the present work is (2,3-epoxypropyl)trimethylammonium chloride. For this thesis, paper grade pulp was cationized in aqueous systems. The effect of different polar organic solvents on reaction efficiency and pulp properties was studied. Partially replacing water with tetrahydrofuran could simulate a higher reagent concentration while maintaining properties such as the extent of supramolecular order (‘crystallinity’) and molar mass distribution. The degree of substitution was determined using classical methods, mostly titration. These were complemented by fast quantification methods developed from observations on changes in the thermodegradation profile as well as in the infrared spectrum of cationized of pulp.

Betreuer: Henniges Ute
1. Berater: Rosenau Thomas
2. Berater: Potthast Antje

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