Self-Healing of Poly(vinyl Alcohol)/Poly(acrylic Acid)–Polytetrahydrofuran–Poly(acrylic Acid) Blend Boosted via Shape Memory

The self-healable polymers that can repair physical damage autonomously to extend their lifetime and reduce maintenance costs are promising intelligent materials. However, utilizing shape memory to facilitate self-repair is unusual at present. In this work, a series of poly(acrylic acid)–polytetrahydrofuran–poly(acrylic acid) polymers (PAA–PTMG–PAA, di PAA–PTMG) are synthesized as a switching phase and healing accelerator to blend into poly(vinyl alcohol) (PVA). The water swelling rate of the blend is up to 400.0% at 1/1 molecular weight ratio of PTMG/PAA and 20.0 wt % blend ratio of di PAA–PTMG to PVA, and its crystallization is changed significantly under wet conditions. The blend membrane exhibits not only a good hydrothermal-response shape memory effect but also a favorable self-healing behavior. The tensile strength and elongation at break are 12.4 MPa and 320.0% after healing at 25 °C, respectively. In particular, the wound membrane can achieve a better self-healing effect with the assistance of shape memory at 37 °C, and the elongation at the break increased to 515.9% after healing. The membrane is not cytotoxic, so it will be a promising biomedical material.