A Water-Triggered Highly Self-Healable Elastomer With Enhanced Mechanical Properties Achieved Using Localized Zwitterionic Assemblies

In this study, the synthesis of a water-triggered highly self-healable elastomer with excellent optical and mechanical properties through localized zwitterionic assemblies is demonstrated for the first time using a newly proposed blending method. The self-healable elastomer obtained by blending conventional polyol and zwitterionic polyol shows a high transmittance (-92%) and low yellow index value (1.9). The fabricated material with localized zwitterionic clusters shows superior self-healing efficiency (94-100%) under both dry and wet conditions compared with conventional nonionic elastomers (-69%) and ionic elastomers with randomly distributed ions (80-87%). This is attributed to the significantly higher probability of contact between the localized zwitterionic assemblies of this material in the damaged area. More importantly, conventional self-healing materials have obtained the self-healing properties of polymers at the expense of their mechanical properties. An elastomer with localized zwitterions eliminates this trade-off between self-healing and mechanical properties. These properties are attributed to the unique intermolecular network resulting from strong interactions between localized zwitterionic clusters. As a result, the zwitterionic self-healable elastomer, based on the blending system proposed in this study, can maximize its self-healing capabilities and overcome the limitations of conventional self-healing materials via the concentration of zwitterions into a local domain.