The processing of cellulose dissolved in ionic liquids (ILs) enables the development of new materials. Besides the established production of cellulosic fiber products, interesting technical applications are developed like super micro filament fibers, cellulose/chitin blend fibers, precursors for carbon fibers, and all‐cellulose composites. This review provides a detailed summary of these new developments and describes how ILs are selected for the processing of cellulose with a particular emphasis on industrial realization. State‐of‐the‐art spinning processes are reviewed and it is illustrated how uniquely selected ILs can be used not only for established fiber spinning but for the development of new cellulose‐based materials.

We report on a new process for the spinning of high-performance cellulosic fibers. For the first time, cellulose has been dissolved in the ionic liquid (IL) 1-ethyl-3-methylimidazolium octanoate ([C2C1im][Oc]) via a thin film evaporator in a continuous process. Compared to other ILs, [C2C1im][Oc] shows no signs of hydrolysis with water. For dope preparation the degree of polymerization of the pulp was adjusted by electron beam irradiation and determined by viscosimetry. In addition, the quality of the pulp was evaluated by means of alkali resistance. Endless filament fibers have been spun using dry-jet wet spinning and an extruder instead of a spinning pump, which significantly increases productivity. By this approach, more than 1000 m of continuous multifilament fibers have been spun. The novel approach allows for preparing cellulose fibers with high Young's modulus (33 GPa) and unprecedented high tensile strengths up to 45 cN/tex. The high performance of the obtained fibers provides a promising outlook for their application as replacement material for rayon-based tire cord fibers.

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We present a new continuous stabilization process for cellulose-derived carbon fibers (CFs) with mechanical properties rivaling those of polyacrylonitrilederived CFs. The novel process enables optimum control over the stabilization process. The effects of process temperature and dwell time on the structure and mechanical properties of the stabilized fibers were investigated by elemental analysis, wide-angle Xray scattering, infrared spectroscopy, scanning electron microscopy, and tensile testing. Laboratory-scale carbonization trials of the stabilized fibers were accomplished in a continuous process at 1400 °C. Received CFs had tensile strengths up to 2.8 GPa and Young's moduli up to 112 GPa. By adjusting the stabilization conditions, the mechanical properties of the resulting CFs can be tuned.

Poly(ethyleneimine) (PEI) immobilized on support materials are valuable alternatives to aqueous amine solutions for carbon dioxide (CO 2 ) capture from the atmosphere since the thermal desorption of CO 2 from these materials usually requires less energy. Herein, fibrous PEI-functionalized carrier systems based on cellulose, cellulose tosylate (CT), and cellulose carbamate (CC) are described. Branched PEI is used for functionalization since higher CO 2 sorption capacities compared to linear PEIs can be achieved. Under wet conditions, a PEI-functionalized nonwoven material has a sorption capacity of 0.026 mg CO 2 /mg adsorbent; complete and reversible CO 2 desorption is accomplished at 80 °C. IntroductionCarbon dioxide (CO 2 ) is a climate-damaging exhaust gas. It can, however, also be used as a resource for plastics or renewable fuels, and thus potentially replace fossil natural gas and crude oil. Adsorption of CO 2 from air is currently under consideration for combating climate change in several respects: it can reduce the amount of the greenhouse gas in the atmosphere, make it usable for the chemical industry and thus enable a reduction in future emissions. Therefore, it is necessary to identify methods for reducing and using the CO 2 being produced and emitted into the