Wax-protected catalyst microspheres for efficient self-healing materials

The microspheres of wax-protected catalyst which contains Grubbs' catalyst and poly(urea-formaldehyde) microcapsules containing liquid dicyclopentadiene (DCPD), for efficient self-healing materials were investigated. The DCPD mixes with the Grubbs' catalyst, which undergoes ring opening metathesis polymerization (ROMP), and cures to provide structural continuity. The reactivity of the wax-embbeded catalyst was quantified by using in-situ ¹H-NMR to measure the ROMP kinetics of endo-DCPD in the presence of microspheres. The results show that even with reduced catalyst concentrations, the use of microspheres produce healing efficiencies.