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In recent years, the interest of the scientific community has become focused on the integration of circular economy principles by eliminating end-of-life concepts and forming zero-waste strategies. The present paper suggests the possible application of innovative, eco-friendly, cost-effective, and highly efficient ceramic materials with the partial implementation of aluminosilicate-based waste in the form of wastewater sludge in advanced technology solutions. The specific objective was to demonstrate the effective utilization of the investigated waste in the production of refractory adhesives and/or sealants for Intermediate-Temperature Solid-Oxide Fuel Cells (IT-SOFCs). Different physical–mechanical and chemical properties were determined along with the performance of leaching tests, the thermal cycling procedure, and leakage tests in a single cell. Based on the maintenance of mechanical integrity after thermal cycling and satisfying crystal and microstructural stability after high-temperature treatment, it was concluded that the investigated materials may be considered promising candidates for application as heat-resistant adhesives for connecting components in heating systems. However, they were not found to be applicable as sealants for IT-SOFCs in raw form according to the failure of testing in a single cell. Still, requirements for this purpose could be met after certain modifications of the composition and synthesis methodology, which presents the major initiative for our further research in this field.

In the present study, supercritical solvent impregnation (SSI) has been applied to incorporate thymol into bio-composite polymers as a potential active packaging material. Thymol, a natural component with a proven antimicrobial activity, was successfully impregnated into starch-chitosan (SC) and starch-chitosan-zeolite (SCZ) films using supercritical carbon dioxide (scCO2) as a solvent. Experiments were performed at 35 °C, pressures of 15.5 and 30 MPa, and an impregnation time in the range of 4–24 h. The highest impregnation yields of SC films with starch to chitosan mass ratios of 1:1 and 1:2 were 10.80% and 6.48%, respectively. The addition of natural zeolite (15–60%) significantly increased the loading capacity of films enabling thymol incorporation in a quantity of 16.7–27.3%. FTIR and SEM analyses were applied for the characterization of the films. Mechanical properties and water vapor permeability of films before and after the impregnation were tested as well. Thymol release kinetics in deionized water was followed and modeled by the Korsmeyer-Peppas and Weibull model. SCZ films with thymol loading of approximately 24% exhibited strong antibacterial activity against E. coli and methicillin-resistant Staphylococcus (S.) aureus (MRSA).

The effect of edge interlaminar stresses on strength of carbon/epoxy laminates of different stacking geometry: cross-ply, quasi-isotropic and angle-ply laminates with additional 0º and 90º ply was studied. Coupons with two widths of laminates with an inverse stacking sequence were tested in static tensile tests. The effect of edge interlaminar stresses on strength was studied, by comparing the values of the tensile strength of laminate coupons of the same width with an inverse stacking sequence, as well as, by comparing the values of the tensile strength of the same lay-up laminate coupons but of different widths. The edge effects were analysed by observing failure, identifying the interlayer where axial cracks at the free edge were initiated or inhibited and by computing interlaminar stresses and strains in the interlayer near the free edge of the coupon. The established edge effect was first correlated to the sign of the normal edge interlaminar stress. The extent of the edge effect was then successfully correlated to the edge interlaminar normal stress normalized to the size of the edge boundary region in which the stress appeared.