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In the field of encapsulation, microcapsules containing perfume have emerged as effective vehicles for delivering active ingredients across various applications. The present study employed a multivariate analysis framework to examine polyacrylate microcapsules for household products synthesized using different acrylate monomers. The advanced multivariate approach allowed us to quantify critical properties such as the Molecular Weight between Cross-links (MWc), mechanical attributes, Encapsulation Efficiency (EE), and On-Fabric delivery. It is worth noting that the mechanical properties were gauged using a novel nanoindentation technique, which measures the Rupture Force per unit diameter (RFD). Both Encapsulation Efficiency and On-Fabric delivery were assessed using GC-MS. Our findings identified the optimal microcapsule system as one synthesized with 100% aromatic hexafunctional urethane acrylate, showcasing a 94.3% Encapsulation Efficiency and an optimal RFD of 85 N/mm. This system achieved an exemplary On-Fabric delivery rate of 307.5 nmol/L. In summary, this research provides crucial insights for customizing microcapsule design to achieve peak delivery efficiency. Furthermore, by designing acrylic monomers appropriately, there is potential to reduce the amount of active ingredients used, owing to enhanced delivery efficiency and the optimization of other microcapsule properties. Such advancements pave the way for more environmentally friendly and sustainable production processes in the fast-moving consumer goods industry.

Fire assay remains the most accurate and precise method for measuring the gold content in gold alloys. Scanning and transmission electron microscopy were used to study the changes in the microstructure of samples during the fire assay process. The results showed that the microstructure of the bead obtained during the cupellation stage was not a perfect Au-Ag binary alloy as expected, but also contained Cu-Ag oxides and other residual compounds. The cornet-shaped product obtained by treating the bead by hammering, flame annealing and rolling showed the presence of surface nano-voids created by dislocation coalescence during annealing. The parting stage in which the Au and Ag are separated to produce a cornet made only of Au appeared to involve a de-alloying process leading to the formation of a nanoporous Au nanostructure. The application of the results to improve the fire assay process is discussed, in particular to avoid cracks inside the cornet which may result in the loss of small pieces of material and errors in Au content measurement., Fire assay remains the most accurate and precise method for measuring the gold content in gold alloys. Scanning and transmission electron microscopy were used to study the changes in the microstructure of samples during the fire assay process. The results showed that the microstructure of the bead obtained during the cupellation stage was not a perfect Au-Ag binary alloy as expected, but also contained Cu-Ag oxides and other residual compounds. The cornet-shaped product obtained by treating the bead by hammering, flame annealing and rolling showed the presence of surface nano-voids created by dislocation coalescence during annealing. The parting stage in which the Au and Ag are separated to produce a cornet made only of Au appeared to involve a de-alloying process leading to the formation of a nanoporous Au nanostructure. The application of the results to improve the fire assay process is discussed, in particular to avoid cracks inside the cornet which may result in the loss of small pieces of material and errors in Au content measurement.