Room-temperature healable, recyclable and mechanically super-strong poly(urea-urethane)s cross-linked with nitrogen-coordinated boroxines

A strong poly(urea-urethane) cross-linked by boroxines shows a high mechanical strength of ∼47 MPa and toughness of ∼190 MJ m⁻³ and it can be healed and recycled at room temperature with the assistance of ethanol or a water/ethanol mixture.