Furan-Modified Spherosilicates as Building Blocks for Self-Healing Materials

Octafunctional spherosilicates were used to prepare self-healing hybrid materials. The hydrosilation of the octakis(hydridodimethylsiloxy)-substituted spherosilicate with furfuryl allyl ether generates an inorganic nano-building-block that is used to formulate various self-healing hybrid materials based on a reversible Diels-Alder reaction. Curing with a molecular bismaleimide results in a hard, glassy but reversibly cross-linkable hybrid material. The reversibility of the curing mechanism allows the preparation of films with a heated press, which also opens the possibility to process the materials by injection molding. Substitution of the molecular cross-linker with an oligomeric poly(dimethylsiloxane) bismaleimide results in an elastomeric material. The kinetics of the Diels-Alder reaction upon cooling after a retro-Diels-Alder reaction are mainly controlled by the mobility of the cross-linker within the system.