A Transparent, Healable and Recyclable Alicyclic Poly(ether-b-amide) Multiblock Copolymer with Ultrahigh Toughness

Self-healing polyamide multiblock copolymer with robust mechanical properties is highly desired. Here, an alicyclic diamine monomer, isophoronediamine (IPDA), with asymmetric structure and substantial steric hindrance was incorporated into the backbone of poly(ether-b-amide) multiblock copolymer. Based on the phase-lock effect, the mechanical properties and segmental mobility of copolymers can be modulated on a large scale via adjusting the molecular weight of hard segments. An extraordinary tensile strength of 32.0 MPa and an excellent elongation at break of 1881 % were simultaneously achieved, which leaded to a record-high toughness of 328.9 MJ m^-3 for self-healable polyamide elastomers. The synergism between the dynamic H-bonding networks and the diffusion of polymer chains contributed to a balance between the mechanical performance and self-healing efficiency of copolymers. Due to the adjustable mechanical performance, rapid scratch self-healing ability and superior impact resistance, the resultant copolymers showed great potential in the fields of protective coatings and soft electronics.