Methods to Monitor and Quantify (Self‐) Healing in Polymers and Polymer Systems

Self‐healing polymeric materials towards non‐structural recovery of functional properties

“…Materials intended for various functional (non‐structural) purposes are widely used in modern society. With the recent development of the science and technology of self‐healing, research on imparting to functional materials the ability to mend and on the corresponding characterization techniques has started . Self‐healing exterior paint that reduces scratches on car surfaces as an aesthetic requirement by means of viscoelasticity driven plastic flow of base polymers (mostly polyurethanes), for example, was launched by the automotive industries .…”

“…With the recent development of the science and technology of self-healing, research on imparting to functional materials the ability to mend and on the corresponding characterization techniques has started. 18 Self-healing exterior paint that reduces scratches on car surfaces as an aesthetic requirement by means of viscoelasticity driven plastic flow of base polymers (mostly polyurethanes), for example, was launched by the automotive industries. 19 However, compared to self-healing structural materials that enable autonomic recovery of strength, 1 -17 functional materials capable of self-healing are relatively less reported on the whole in terms of materials species and functionalities involved.…”

A review of the recent development in self-healing rubbers and their quantification methods

“…The heat is used to convert the polymeric material to a viscoelastic melt state and heal the damage by reconstructing ionic interactions within the polymer system. 4,109 The local heat is said to approach the melting temperature; however, the extent of heat is not easy to measure. Rahman et al 56 reported the self-healing properties of ENR with two different epoxidation levels (25 and 50 mol % epoxidation, respectively) based on the ballistic puncture test.…”

“…Another advantage of this method is that the realignment of the geometry is relatively easy when a partial fracture occurs. 109 TDCB has been widely used to test extrinsic self-healing polymers such as the self-healing epoxy nanocomposites designed by Guadagno et al 110 In this study, they evaluated the healing efficiency of epoxy composites loaded with different types of carbon nanotubes. The composite samples were introduced with a pre-crack to sharpen the crack tip and subjected to displacement to propagate the crack along the centreline of the sample.…”

“…Thus, it is crucial to evaluate the fatigue lifespan and fatigue resistance of self-healing rubbers, which can potentially be exposed to high cyclic loading when in service. 102,109 The healing process occurs simultaneously when the energy accumulates within the material system during fatigue loading. Therefore, it is suggested that a faster healing rate is desired to enhance fatigue crack resistance.…”