Biomass polyamide elastomers based on hydrogen bonds with rapid self-healing properties

By the polycondensation reaction of high-purity dimer acid (DA) and diethylene triamine (DETA), a polyamide elastomer (DPE) with rapid self-healing ability was successfully prepared. In the DPE networks, long polymer chains are physically entangled with each other. Chemical crosslink also occurred between amide groups and secondary amine structures. Besides, numerous hydrogen bonds formed among the amide bonds of different segments endowed the DPE with self-healing ability at room temperature. As a result, triple effects of cross-linking, physical entanglement and hydrogen bonding improve the mechanical properties of DPE. The tensile strength and elongation at break reached 4.5 MPa and 1700%, respectively. Self-healing efficiency of DPE can reach 80% within 2 h. This material can be utilized for many practical applications, such as smart wearable devices, e-skins and so on.