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Antimicrobial finishes for textiles and other surfaces that act without the release of biocides to the environment (contact biocides) or by inhibiting microbial adhesion (antifouling action) are viewed as promising and environmentally friendly alternatives to current products. We have used polyvinylamine polymers that were functionalized with zwitterionic sulfobetaine side chains with different degrees of substitution (DS) for the finishing of poly(ethylene terephthalate) (PET) and cotton fabrics in a water-based pad-dry-cure process. After washing with different surfactants, a stable finish with total polymer add-ons of 0.2-0.5 wt% was achieved. The finished textiles efficiently inhibited the adhesion of proteins and bacteria to the surface even with a small DS as low as 20%. Textiles finished with polymers with a low DS also showed significant antibacterial activity, most notably against Staphylococcus aureus . Accordingly, textile finishes with either pure antiadhesive (DS > 50%) or combined antiadhesive and antibacterial properties (DS = 20-50%) are accessible using this approach., Competing Interests: There are no conflicts to declare., (This journal is © The Royal Society of Chemistry.)

A comprehensive study combining detailed computational analyses with temperature-variable FT-IR experiments was performed in order to elucidate the structure of the hydrogen-bonded liquid crystals based on phloroglucinol and azopyridine in their mesophase. Conformational analysis revealed three relevant conformers: star, λ- and E-shape. The results demonstrate an entropy-driven unfolding mechanism of the assembly. The stability of the conformers is given by intermolecular π-π and dispersion interactions of the azopyridine side chains. Correlating the calculated vibrational frequency with experimental FT-IR spectra suggests a λ-folded conformation of the assemblies as the predominant species in the mesophase., Competing Interests: The authors declare no conflict of interest., (This journal is © The Royal Society of Chemistry.)

In this work, a pioneering study on the electrical properties of composite carbon nanofibres (CNFs) using current-sensitive atomic force microscopy (CS-AFM) has been demonstrated. CNFs are highly interesting materials which are usable in a wide array of applications e.g. electrode materials for biosensors, lithium ion batteries, fuel cells and supercapacitors. CNFs offer a high specific surface area and thus have a high contact area for charge transfer. CNFs can be produced using spinnable polyacrylonitrile (PAN) as a precursor for carbonisation. For the purpose of developing efficient CNFs with high conductivity and power density, silver nanoparticle (AgNPs)-containing PAN solutions were electrospun to form composite nanofibres which was followed by heat treatment. The applied voltage of the spinning setup and the content of both PAN and the silver nanoparticles in the spinning solution were varied in order to study their influence on the morphology and the electrical properties of the nanofibres. The resultant morphologies and fibre diameters were determined by scanning electron microscopy (SEM). The formation of silver nanoparticles was characterised in solution by UV-visible absorption spectroscopy and dynamic light scattering (DLS), while energy-dispersive X-ray spectroscopy (EDX) and transmission electron microscopy (TEM) were carried out to investigate the presence as well as the average diameter of the AgNPs. The electrical properties of the CNFs were investigated using CS-AFM. This technique gives us the possibility to explore the electrical properties of single fibers and hence derive relationships between the structural features and the electrical properties. Our results show that the composite CNFs have a higher electrical conductivity than the neat CNFs and both the average diameter of the fibers and the electrical conductivity increase with an increasing AgNP content., Competing Interests: There are no conflicts to declare., (This journal is © The Royal Society of Chemistry.)