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Abstract: This feature article covers the recent developments of amyloid fibrils as templates for organic–inorganic hybrid aerogels. It aims at introducing the reader to amyloid fibril functional bio‐nanomaterials and to show how, building on the prior art of colloidal aerogels, these anisotropic colloids can be used to template inorganic particles and to form gels and aerogels. Specifically, hybrid organic–inorganic amyloid fibril templated gold, silver, and calcium aerogels are discussed focusing on their material synthesis and how the preparation conditions can be tuned to vary the final materials' optical, structural, and mechanical properties. The colloidal processing methodology offers a convenient route to form gels and aerogels that maintain the nanoscopic dispersion properties within the formed monoliths. These ultralight porous materials are appealing for a diverse set of applications within food, fine arts, jewelry, and biomedicine. Here their use as pressure sensor, catalysis membrane, and antibacterial material are described and further applications based on the properties of the specific inorganic particles and hybrid aerogels are discussed. [ABSTRACT FROM AUTHOR]

Through a straightforward approach, a new meltable, halogen-free, nitrogen-phosphorus-based flame retardant (FR), 6-(2-(4,6-diamino-1,3,5-triazin-2-yl)ethyl) dibenzo[c,e][1,2]oxaphosphinine 6-oxide (DTE-DOPO) was synthesized and incorporated in polyamide 6 (PA6). It was proved that a very low phosphorus content of 1.46 wt % for DTE-DOPO additive improved the flame retardancy of PA6, leading to a non-flammable material. The performance of the new additive was compared to that of the commercially-available Exolit® OP 1230. The PA6 formulations were evaluated by measuring the rheological, mechanical, and flammability behavior. Using compounding by melt extrusion, 17 wt % additives was introduced into PA6 matrix and the corresponding formulations were characterized. The results evidenced a higher homogeneity of DTE-DOPO with PA6, a high thermal stability with a catalyzing decomposition effect on PA6 caused by the presence of the new developed FR, enhanced elasticity for the PA6/DTE-DOPO formulation and a V0 rating for both formulations. Thermal and fire analysis indicated a primary gas-phase activity, combined with a complete suppression of the self-sustained burning for the PA6/DTE-DOPO formulation. [ABSTRACT FROM AUTHOR]

The use of oleoresin as natural colorant is widely used in daily food and beverages. However, there is still a lack of information about the solid-liquid extraction process to obtain this oily extract from sweet paprika. The effects of different operating variables, such as extraction technique, temperature, powder-to-solvent ratio and type of solvent on oleoresin extraction, were investigated through experiments and the leaching process was theoretically modeled. The results indicated that although extraction yields are not affected by the extraction technique, ultrasound-assisted extraction reduces the extraction time required to achieve them. Hexane as solvent and 298 K were the conditions to reach higher coloring capacities of the extracted oleoresins and, thus, they were selected to model the process. Calculations report a powder-to-solvent ratio of 1:4.3 to obtain the maximum oleoresin recovery (84 wt %) in one single contact stage. Practical Applications In this work, the results obtained from the detailed study about the effect of operating variables on the oleoresin extraction throw light on this process, enhancing the knowledge of the conventional production process and opening new possibilities to achieve the industrial extraction of sweet paprika. In this context, ultrasound-assisted extraction has been proved to be an efficient technique to obtain similar extraction yields to those from the conventional process, but reducing by a factor of at least 24 the extraction times. Furthermore, the modeled results can serve for further scale-up of paprika companies. [ABSTRACT FROM AUTHOR]