Sökning: "melt spinning"
Visar resultat 11 - 15 av 17 avhandlingar innehållade orden melt spinning.
11. Biobased carbon fibers from solution spun lignocellulosic precursors
Sammanfattning : Carbon fibers (CFs) have excellent mechanical properties and a low density, making themattractive as a reinforcing fiber in composites. The use of CFs is limited to high-end applications,since they are produced from an expensive fossil-based precursor via an energy-intensivemanufacturing process, explaining the need for cheaper CFs from renewables. LÄS MER
12. Processing of continuous fibers based on nanocellulose: Influence of dispersion and orientation on mechanical properties
Sammanfattning : The aim of the work was to prepare continuous bio-based fibers where nano-sized cellulose was used to improve the mechanical properties. Two different strategies were used to reach this aim, melt-spinning of thermoplastic fibers reinforced with nanocellulose and dry-spinning of cellulose nanofibers without solvent or chemicals. LÄS MER
13. Process and properties of continuous fibers based on cellulose nanocrystals and nanofibers
Sammanfattning : In recent years, composites made from natural fibers based on cellulose have received increasing attention since they have a low environmental impact and good mechanical properties. However, these fibers are short and discontinuous and the conventional spinning techniques used for these fibers results in continuous yarns with mechanical properties considerably lower than that of the single fibers. LÄS MER
14. Development of softwood kraft lignin based carbon fibers
Sammanfattning : The polymer composites designed for high-performance applications are mostly based on carbon fiber reinforcement. The two most common precursors used currently for carbon fiber production are poly(acrylonitrile) and pitch (petroleum- or coal- based). As of today, the most promising alternative to these fossil originated raw materials is lignin. LÄS MER
15. Composition-Structure Correlations of Bioactive Glasses Explored by Multinuclear Solid-state NMR Spectroscopy
Sammanfattning : This PhD thesis presents a study of structure-composition correlations of bioactive glasses (BGs) by employing solid-state Nuclear Magnetic Resonance (NMR) spectroscopy.Silicate-based Na2O−CaO−SiO2−P2O5 BGs are utilized clinically and are extensively investigated for bone regeneration purposes. LÄS MER