Multifunctional Polymers and Composites for Self-Healing Applications

Mechanical deformation can be used to activate specific reaction pathways in mechanochemical triggers designed to harness the energy in a polymer under stress. Since activation of these triggers occurs before chain scission, we feel that they will be useful for the development of self-toughening polymeric materials. Upon activation, the oQDM intermediates could react with pendant dienophiles to form new crosslinks. The formation of crosslinks would be directly coupled and tailored to the stress field in a failing polymer. We also feel, with slight modification, that mechanochemical triggers could be useful for the stress-induced formation of new chromophores. The newly formed chromophores could then signal that some critical load has been reached, or perhaps signal the presence of microcracks. We expect that the procedures reported here will be generally useful for the development of utilizing mechanical energy to activate specific chemical pathways, and help shift the major focus of mechanochemical studies from bond-breaking to bond-making transformations.