Sökning: "Cellulose II"
Visar resultat 1 - 5 av 85 avhandlingar innehållade orden Cellulose II.
1. Mercerization and Enzymatic Pretreatment of Cellulose in Dissolving Pulps
Sammanfattning : This thesis deals with the preparation of chemically and/or enzymatically modified cellulose. This modification can be either irreversible or reversible. Irreversible modification is used to prepare cellulose derivatives as end products, whereas reversible modification is used to enhance solubility in the preparation of regenerated cellulose. LÄS MER
2. Experimental study of alkalinisation of cellulose in industrial relevant conditions
Sammanfattning : Mercerisation of cellulose pulp with a solution of NaOH is the first step of manufacturing cellulose-based value-added products, e.g. viscose fibres and cellulose ethers. During this process, cellulose transforms into a swollen crystalline structure, alkali cellulose (Na-Cell). LÄS MER
3. Tailoring Cellulose Nanofibrils for Advanced Materials
Sammanfattning : Cellulose nanofibrils (CNFs) are nanoscale fibers of high aspect ratio that can be isolated from a wide variety of cellulosic sources, including wood and bacterial cellulose. With high strength despite of their low density, CNFs are a promising renewable building block for the preparation of nanostructured materials and composites. LÄS MER
4. Structural changes during cellulose composite processing
Sammanfattning : Two approaches for creating a new all-cellulose composite material have been studied: the biosynthesis of compartmentalised bacterial cellulose fibril aggregates and the compression moulding of commercial chemical wood pulps processed with only water. The objective was to study the structural changes during processing and the complexity of relating the mechanical properties of the final biocomposites to the nanoscale structure was highlighted. LÄS MER
5. Manufacturing and Characterization of Cellulose Nanofibers
Sammanfattning : The usage of wood has been a dominant driving force during the evolution of the human species. It allowed us to cook food, build tools, put roofs over our head and explore the world. The fibers making up the tree has been the most important way to store and transmit knowledge in the form of paper for centuries. LÄS MER