Maximizing the symbiosis of static and dynamic bonds in self-healing boronic ester networks

Abstract

Networks that contain boronic ester crosslinks undergo dynamic bond exchange that enables self-healing behavior and reprocessing.

Dynamic Covalent Bonds in Polymeric Materials

“…Alternatively, some adducts undergo efficient exchange in the absence of stimulus (e.g. boronates, boronic esters, certain Diels–Alder adducts), and these materials can have enhanced mechanical stability when a nondynamic linker is incorporated . The choice of DCBs greatly depends on the intended application; for instance, a thermoresponsive bond could be well suited to a high‐temperature adhesive, coating, or sealant application, while a material responsive to mild pH may be better suited to biomaterials applications.…”

“…This broad pH range is useful in biomedical applications, as recently reported for 2‐APBA‐ and PVA‐linked hydrogels, which are self‐healing in cell culture media (Figure ) . Additionally, dynamic boronic ester formation can be extended to self‐healing bulk polymeric materials …”

Vitrimers: directing chemical reactivity to control material properties

“…A similar concept was in fact simultaneously reported by Sumerlin and co-workers in the context of self-healing boronic ester networks. 58 Recently, the idea was further taken up by Nicolaÿ and co-workers in polybutadiene vitrimers 59 and by our group in vinylogous urethane epoxy-based vitrimers. 60 While this concept represents an effective 'generic' strategy to suppress creep, the reprocessability also suffers qualitatively and quantitatively, and it seems hard to overcome this intrinsic limitation.…”

Bouncing and 3D printable hybrids with self-healing properties

“…Some self-healing materials have been found to be susceptible to creep and stress-relaxation and their mechanical stability was increased by the addition of permanent crosslinks at the expense of healing efficiency. 50 Stress-relaxation tests were performed on our Si0-CL (highest self-healing ability) and…”