The anchorage of a supported copper Schiff base complex on SBA-15 materials provides highly efficient heterogeneous catalysts towards the solvent-free synthesis of dihydropyrimidinones derivatives via the Biginelli condensation reaction. The novel nanocatalysts exhibited a highly ordered mesostructure with a surface area of 346 m2g−1 and an average pore diameter of 8.6 nm. Additionally, the supported copper nanocatalysts were reused at least ten times, remaining almost unchanged from the initial activity. Both the mesoporous scaffold and the tridentate Schiff base ligand contributed to the stabilization of copper species.

In this study, 1,8-dioxo-octahydroxanthenes were prepared employing a simple, effective and environmentally sound approach utilizing an iron oxide nanocatalyst under solventless conditions. The proposed iron oxide nanomaterial exhibited high product yields, short reaction times and a facile work-up procedure. The synthesized catalyst was also found to be highly stable and reusable under the investigated conditions (up to twelve consecutive cycles) without any significant loss in its catalytic activity.

Flexible polyurethane nanocomposites (PUNCs) containing recycled polyether polyols received from chemical recycling of original corresponding foams were synthesized by the incorporation of organically functionalized Cloisite 30B montmorillonite (MMT). Different amounts of MMT (1-3%w) were added to the polyol mixture prior to introducing the isocyanate portion. Recycled polyol was ranged between 10 to 30% of total polyol and MMT was maximum 3%. Thermal, morphological and mechanical properties of prepared PUNCs were studied and the results demonstrated the improvement of properties.