Phase-Separation-Induced Anomalous Stiffening, Toughening, and Self-Healing of Polyacrylamide Gels

Novel, tough, strong, and self-healable polyacrylamide (PAAm) gels are fabricated by inducing an appropriate phase-separation structure using a poor solvent. The phase separation induces a gel-glass-like transition of the PAAm gels, providing the gels an anomalously high modulus (211 MPa), fracture stress (7.13 MPa), and fracture energy (4.16 x 10(4) J m(-2)), while keeping a high solvent content (approximate to 60 vol%).