Tannins are eco-friendly, bio-sourced, natural, and highly reactive polyphenols. In the past decades, the understanding of their versatile properties has grown substantially alongside a continuously broadening of the tannins’ application scope. In particular, recently, tannins have been increasingly investigated for their interaction with other species in order to obtain tannin-based hybrid systems that feature advanced and/or novel properties. Furthermore, in virtue of the tannins’ chemistry and their high reactivity, they either physicochemically or physically interact with a wide variety of different compounds, including metals and ceramics, as well as a number of organic species. Such hybrid or hybrid-like systems allow the preparation of various advanced nanomaterials, featuring improved performances compared to the current ones. Consequently, these diverse-shaped materials have potential use in wastewater treatment or catalysis, as well as in some novel fields such as UV-shielding, functional food packaging, and biomedicine. Since these kinds of tannin-based hybrids represent an emerging field, thus far no comprehensive overview concerning their potential as functional chemical building blocks is available. Hence, this review aims to provide a structured summary of the current state of research regarding tannin-based hybrids, detailed findings on the chemical mechanisms as well as their fields of application.

Selective removal of nanometer-sized compounds such as proteins from fluids is an often challenging task in many scientific and industrial areas. Addressing such tasks with highly efficient and selective membranes is desirable since commonly used chromatographic approaches are expensive and difficult to scale up. Nanomembranes, molecularly thin separation layers, have been predicted and shown to possess outstanding properties but in spite ultra-fast diffusion times and high-resolution separation, to date they generally lack either of two crucial characteristics: compatibility with biological fluids and low-cost production. Here we report the fast and easy fabrication of highly crosslinked polymer membranes based on a thermoset resin (poly[(o-cresyl glycidyl ether)-co-formaldehyde (PCGF) cured with branched polyethyleneimine (PEI)) with nanoscale perforations of 25 nm diameter. During spin casting, microphase separation of a polylactide-co-glycolide induces the formation of nanometer sized domains that serve as templates for perforations which penetrate the 80 nm thick membranes. Ultrathin perforated nanomembranes can be freely suspended on the cm scale, exhibit high mechanical strength, low surface energies and a sharp permeability cutoff at a hydrodynamic diameter of 10 nm suitable for protein separations.

In this paper the electrical package design for a 10 Gbps laser diode on a silicon optical bench will be presented. Specifically the wideband impedance matching is addressed. Simulated data will be compared to measurements.

Nanostructured metal assemblies on thin and ultrathin polymeric films enable state of the art technologies and have further potential in diverse fields. Rational design of the structure–function relationship is of critical importance but aggravated by the scarcity of systematic studies. Here, we studied the influence of the interplay between metal and polymer surface free energy and reactivity on the evolution of electric conductivity and the resulting morphologies. In situ resistance measurements during sputter deposition of Ag, Au, Cu and Ni films on ultrathin reticulated polymer films collectively reveal metal–insulator transitions characteristic for Volmer–Weber growth. The different onsets of percolation correlate with interfacial energy and energy of adhesion weakly but as expected from ordinary wetting theory. A more pronounced trend of lower percolation thickness for more reactive metals falls in line with reported correlations. Ex situ grazing incidence small angle X-ray scattering experiments were performed at various thicknesses to gain an insight into cluster and film morphology evolution. A novel approach to interpret the scattering data is used where simulated pair distance distributions of arbitrary shapes and arrangements can be fitted to experiments. Detailed approximations of cluster structures could be inferred and are discussed in view of the established parameters describing film growth behavior.

Alternative separation methods operating in an aqueous environment are of increasing importance for further progress of molecular separation in life sciences and other industrial sectors working towards a biobased economy. By spincoating, membranes with thicknesses under 100 nm and 20 cm(2) surface area were prepared from an epoxy based resin. For the first time such ultrathin epoxy films were used for the selective separation of small molecules and metabolites within an aqueous environment. Initially, selectivity is demonstrated by the separation of two dyes of similar size (0.7 and 1.4 nm diameter). By variation of the precursor concentrations, both mechanical stability and selectivity for molecular transport are shown to be tunable. The observed transport properties of the different membranes correlated with their biaxial moduli and ultimate tensile strengths which were in the range of 0.3-3.5 GPa and 10-44 MPa, respectively. These observations agreed with the conclusion drawn from FTIR analysis that variations in the covalent crosslinking density determine the emergent properties. Finally, permeation rates for small molecules of industrial relevance were assessed to confirm a size based diffusion cutoff for compounds with hydrodynamic diameters below 2 nm.

Ultrathin mesoporous membranes offer highly desirable characteristics for separation tasks regarding selectivity and mass transport of proteins. They have potential applications as separation devices in microfluidics, diagnostics, sensing, and high‐precision separations for pharmaceutical formulation. Especially for large‐scale and mass production, sophisticated production processes represent a barrier for wider application. A method is developed to produce nanomembranes with a thickness of 75 nm and 40 nm pores with an epoxy resin. The novolac resin is cured with branched polyethylenimine to form a covalently crosslinked polymer membrane with perforations spanning the entire thickness. Pore formation relies on micro‐phase separation of the curing agent during casting and the selective dissolution of the emergent nanodomains which thereby serve as pore templates. The resulting membranes are hydrophilic and therefore suitable for applications with biological fluids. Mechanical testing of the flexible but robust thin films reveals an ultimate tensile strength of 15 MPa and a biaxial modulus of 0.8 GPa. Proteins with a diameter of less than 12 nm can diffuse through the pores and permeation rates are pH dependent. The entire fabrication process is transferred to a dip‐coating approach, which is more suitable for a potential large‐scale production.