In this paper, the oxy-fluorination process and the influence of different concentrations of fluorine and oxygen in the gas phase on the physicochemical properties of polyacrylonitrile(PAN)-based carbon fibers are described. The properties of the treated carbon structures are determined by zeta potential and tensiometry measurements. In addition, changes in surface composition and morphology are investigated by X-ray photoelectron spectroscopy (XPS) and scanning electron microscopy (SEM). Adhesion properties are characterized by the single fiber pull-out (SFPO) test. Furthermore, changes in intrinsic properties are described by means of tensile and density measurements. After a primary desizing effect by oxy-fluorination, an increased number of oxygen-containing surface functional groups could be detected, which led to more debonding work in SFPOs with an epoxy-based matrix. It was also shown that the polar surface energy grows with rising fluorine concentration in the reaction gas mixture. In addition, a minor increase of ~10% in the maximum strength of PAN-based carbon fibers is detected by single fiber tensile measurements after oxy-fluorination with a fluorine content of 5% in the reaction mixture.

Ionic liquids offer alternative methods for the sustainable processing of natural biopolymers like chitosan. The ionic liquid 1-butyl-3-methylimidazolium acetate (BmimOAc) was successfully used for manufacturing of pure chitosan-based monofilaments by a wet spinning process at lab-scale. Commercial chitosan with 90% deacetylation degree was used for the preparation of spinning dopes with solids content of 4–8 wt.%. Rheology tests were carried out for the characterization of the viscometric properties. BmimOAc was used as a solvent and deionized water as coagulation and washing medium. Optical (scanning electron microscope (SEM), light microscope) and textile physical tests were used for the evaluation of the morphological and mechanical characteristics. The manufactured chitosan monofilaments a homogeneous structure with a diameter of ~150 μm and ~30 tex yarn count. The mechanical tests show tensile strengths of 8 cN/tex at Young’s modulus up to 4.5 GPa. This work represents a principal study for the manufacturing of pure chitosan fibers from ionic liquids and provides basic knowledge for the development of a wet spinning process.

The unique properties of silica, such as biocompatibility and the ability to promote cell growth, demonstrate favorable results in different applications such as drug delivery, biomedical applications, and tissue engineering (TE). Electrospinning has emerged as a method for creating a substrate with a high surface area and structural resemblance to natural extracellular matrices. A common method of fabricating silica nanofibers (SNFs) for TE involves hybrid silica/ polymer nanofibers, which require calcination to remove the polymer and obtain pure silica. This study aimed to use the sol‐gel precursor tetraethyl orthosilicate (TEOS) to fabricate pure SNFs through electrospinning and investigate calcination's effect on their morphology, thermal behavior, mechanical properties, wettability, and porosity. The findings indicated that the calcination process reduced Young's modulus, wettability, and porosity, which may influence the applications of SNFs in TE. Nanofibrous mats with high Young's modulus can play a crucial role in providing mechanical support for tissue repair. Additionally, high porosity and wettability can facilitate cell attachment and growth by improving nutrient and oxygen transport to the cells. This study provides valuable insights into the potential use of pure SNFs and highlighted the effects of heat treatment on their properties.