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

Adv Mater. 2015 Nov 18;27(43):6990-8. doi: 10.1002/adma.201502967. Epub 2015 Oct 1.

Abstract

Novel, tough, strong, and self-healable poly-acrylamide (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 × 10(4) J m(-2)), while keeping a high solvent content (≈60 vol%).

Keywords: phase separation; polymer gels; sacrificial bonds; self-healing; toughening.