The influence of molecular structure on the mechanical properties of self-assembled 1,3,5-benzenetrisamide nanofibers is investigated. Three compounds with different amide connectivity and different alkyl substituents are compared. All the trisamides form well-defined fibers and exhibit significant differences in diameters of up to one order of magnitude. Using nanomechanical bending experiments, the rigidity of the nanofibers shows a difference of up to three orders of magnitude. Calculation of Young's modulus reveals that these differences are a size effect and that the moduli of all systems are similar and in the lower GPa range. This demonstrates that variation of the molecular structure allows changing of the fibers' morphology, whereas it has a minor influence on their modulus. Consequently, the stiffness of the self-assembled nanofibers can be tuned over a wide range--a crucial property for applications as versatile nano- and micromechanical components.

Self-assembling small molecules is considered a promising technology for fabricating micro-and nanosized features. Utilization of typical top-down approaches, such as electrospinning, is rare in combination with self-assembly. Here we report for the first time on melt electrospinning of 1,3,5-cyclohexane-and 1,3,5-benzenetrisamides into fibres. The fibre spinning conditions were investigated with respect to the type of mesophase and applied field strength. It is possible to electrospin fibres from the nematic liquid crystalline phase and, most surprisingly, also from the optical isotropic state slightly above the clearing temperature, but not from columnar LC phases. Under optimized conditions it is possible to prepare homogeneous fibres with diameters below 1 mm.

Electrospinning is an attractive way to prepare nano‐ and macrofibers. It was demonstrated by our group that trisamides can be melt electrospun into supramolecular fibers. To establish structure–property relationships regarding spinnability and morphology, melt electrospinning experiments were conducted using several classes of compounds. The number of hydrogen bonds was systematically decreased from three for trisamides, to two for bisamide and sorbitols, and to zero for perylene bisimides and tertiary trisamides. As a result, trisamides are readily spun into fibers, whereas for bisamides and sorbitols mainly electrospraying into spheres is observed. Perylene bisimides form well‐defined fibers due to strong π–π interactions. This supramolecular fiber is interesting for many scientific disciplines.

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Front Cover: Electrospinning is an attractive technique to generate supramolecular macro‐ and nanofibers. Here, a comprehensive structure‐property relationship between chemical structure, spinnability, and fiber morphology is presented for several classes of small molecules. For the characterization of electrospun morphologies, scanning electron microscopy (SEM) is the tool of choice. Among thousands of images taken in the course of a project, some pictures reveal very peculiar and curious details, with Pinocchio shown as the center piece. To discover such images during hours of tedious SEM work demonstrates that science can be a lot of fun. Further details can be found in the article by J. C. Singer, A. Ringk, R. Giesa, and H.‐W. Schmidt* http://doi.wiley.com/10.1002/mame.201400296.