Smart and Covalently Cross-Linked: Hybrid Shape Memory Materials Reinforced through Covalent Bonds by Zirconium Oxoclusters.

The first examples of organic-inorganic hybrid materials reinforced by transition-metal oxoclusters that exhibit shape memory properties, based on the covalent incorporation of zirconium-based inorganic building blocks, are reported. Methacrylate-functionalized zirconium oxoclusters Zr O (OMc) and [Zr O (OH) (OOCCH CH ) {OOCC(CH )=CH } ] , with the covalent incorporation in a butyl acrylate (BA)/polycaprolactone dimethacrylate (PCLDMA) copolymer and the noncovalent incorporation of [Zr O (OH) (OOCCH CH ) ] are focused upon herein. Shape recovery and fixity rates are studied to observe if the shape memory properties are preserved upon going from a simple copolymer to noncovalent or covalent-based hybrids.