Adding three-dimensional printed objects on existing surfaces enables creation of multi-material objects with tailored mechanical properties. Especially, the tensile strength of a textile fabric is advantageous in comparison with threedimensional printed polymeric parts, while the latter can increase the stiffness of the composite. The adhesion forces between both material partners, however, are crucial for the reliability of the multi-material object. While several printing and material properties have been shown to influence the adhesion previously, this article concentrates on the possible pretreatment methods for three-dimensional printing on a cotton fabric. In our experiments, we have shown that especially pretreatments which made the textile surface more hydrophobic or more hydrophilic resulted in significant modifications of the adhesion forces. In addition, the adhesion is influenced by the infill orientation, with an orientation of 90°being significantly advantageous compared to 0°. While surface roughness was also shown to depend on the infill angle, no significant differences of the tensile strength or the elongation at break were measured.

Electrospun nanofiber mats may serve as new hardware for neuromorphic computing. To enable data storage and transfer in them, they should be magnetic, possibly electrically conductive and able to respond to further external impulses. Here we report on creating magnetic nanofiber mats, consisting of magnetically doped polymer nanofibers for data transfer and polymer beads containing larger amounts of magnetic nanoparticles for storage purposes. Using magnetite and iron nickel oxide nanoparticles, a broad range of doping ratios could be electrospun with a needleless technique, resulting in magnetic nanofiber mats with varying morphologies and different amounts of magnetically doped beads.

Magnetic nanofibers are of great interest in basic research, as well as for possible applications in spintronics and neuromorphic computing. Here we report on the preparation of magnetic nanofiber mats by electrospinning polyacrylonitrile (PAN)/nanoparticle solutions, creating a network of arbitrarily oriented nanofibers with a high aspect ratio. Since PAN is a typical precursor for carbon, the magnetic nanofiber mats were stabilized and carbonized after electrospinning. The magnetic properties of nanofiber mats containing magnetite or nickel ferrite nanoparticles were found to depend on the nanoparticle diameters and the potential after-treatment, as compared with raw nanofiber mats. Micromagnetic simulations underlined the different properties of both magnetic materials. Atomic force microscopy and scanning electron microscopy images revealed nearly unchanged morphologies after stabilization without mechanical fixation, which is in strong contrast to pure PAN nanofiber mats. While carbonization at 500 °C left the morphology unaltered, as compared with the stabilized samples, stronger connections between adjacent fibers were formed during carbonization at 800 °C, which may be supportive of magnetic data transmission.

Three-dimensional printing belongs to the emerging technologies of our time. Still being relatively time-consuming and suffering from low mechanical properties, three-dimensional printing can be combined with other production technologies to overcome these problems. Three-dimensional printing on textile fabrics, for example, allows for creating large areas with sufficient lateral mechanical properties in a reasonable time on which three-dimensional printed parts give additional functionalities or laterally selective mechanical rigidity and so on. To create three-dimensional printed personalized knee joint support bandages, however, the adhesion between textile fabric and polymeric parts needs to be further increased. Here, we report on the influence of a polymer coating on different textile fabrics on the adhesion of three-dimensional printed elements from hard and soft poly(lactic acid). Surprisingly, the coating increases the adhesion significantly for the hard poly(lactic acid), while the soft poly(lactic acid) sticks better on some materials without additional coating. Maximum separation forces are measured for linen which can be attributed to the relatively long linen fibers with uneven surface, increasing the fiber-fiber friction inside the fabric and the adhesion to the polymer.

Pleurotus ostreatus is a well-known edible mushroom species which shows fast growth. The fungus can be used for medical, nutritional, filter, or packaging purposes. In this study, cultivation experiments were carried out with Pleurotus ostreatus growing on polyacrylonitrile (PAN) nanofiber mats in the presence of saccharose and Lutrol F68. The aim of this study was to find out whether modified PAN nanofiber mats are well suited for the growth of fungal mycelium, to increase growth rates and to affect mycelium fiber morphologies. Our results show that Pleurotus ostreatus mycelium grows on nanofiber mats in different morphologies, depending on the specific substrate, and can be used to produce a composite from fungal mycelium and nanofiber mats for biomedical and biotechnological applications.