Production and characterization of functional regenerated cellulose fibers having enhanced thermal properties

In recent years, the number of researches on sustainability, renewable materials and recycling has been increasing in the textile sector as well as in many branches of the industry. Therefore, two significant topics that became important for textile industry namely 'providing sustainability by reusing of textile wastes' and 'developing high-valued new textile raw materials considering the innovations in fiber modification techniques'. In this context, the topic of this thesis is determined as production of thermally improved regenerated cellulose fibers with additives by using recycled cellulose from waste vegetable fibers and investigating the properties of obtained fibers. In the thesis, cellulose samples obtained from waste jute fibers released during the textile production process were used as raw materials. Commercial cellulose was also used in the fiber spinning. Both cellulose samples were dissolved in N-methylomorpholine-N-oxide and neat regenerated cellulose fibers were obtained by using solution spinning method. After then, composite regenerated fibers were produced by using different additives during fiber spinning. Graphene oxide and halloysite particles were used as additives in different ratios. Test results of neat and composite fiber samples, which were produced by using two cellulose samples, were investigated in three main topics: morphologically, structural and in terms of thermal properties. To investigate the surface and cross-sectional properties of fibers optical microscopy were used. Images have shown that the additive didn't cause any deterioration. FTIR analyses were carried on to investigate the structural properties of fibers have shown that all fiber samples have similar functional groups. This result arises from the similarity of elemental properties of all constituents that form the fiber structures. XRD analyses were carried on to investigate the fine structures of the fiber samples have shown that all samples present typical diffraction of cellulose I structure. In addition to this result, crystallization degree of fibers including additives increased a sum of due to nucleus effect of the additives at the crystal center. The moisture absorption capacity of the composite fibers is also quite high compared to the neat fibers. Thermal analysis results of neat and composite fibers, produced from different cellulose samples, have shown that increase in the parameters of degradation temperature and flame retardancy for composite fibers. For the fibers produced by using recycled cellulose; composite fibers, have shown enhanced thermal behavior with respect to neat fibers. Consequently, in this study sustainability of cellulose was accomplished by recycling a valuable polymer from waste vegetable fibers and re-submitted to the production process. As a result of regenerated cellulose fiber spinning trials in laboratory scale, composite regenerated cellulose fibers having enhanced thermal properties were also produced. The results of this thesis will both provide scientific, and social information on this topic to the researchers and will lead to plan following studies.