A Solvent Co-cross-linked Organogel with Fast Self-Healing Capability and Reversible Adhesiveness at Extreme Temperatures

ACS Appl Mater Interfaces. 2020 Jul 1;12(26):29757-29766. doi: 10.1021/acsami.0c04933. Epub 2020 Jun 21.

Abstract

Antifreezing gels are promising in diverse engineering applications such as structural soft matters, sensors, and wearable devices. However, the capability of fast self-healing and reversible adhesiveness still remain a huge challenge for gels at extreme temperatures. Here, we proposed a solvent-involved cross-linking system composed of polyacrylic acid, polyvinyl alcohol, borax, ethylene glycol, and water, capable of antifreezing below -90 °C. It was not only antifreezing, anticrystalline, and abundant in dynamic bonds but also highly transparent, stretchable (over 800%), and conductive over the scope of temperature from -60 to 60 °C. Moreover, this gel could self-heal within 1 min and repeatedly adhere to multiple substrates including glass, metal, and rubber with an adhesive strength greater than 18 kPa. These key functions of the gel could be mostly preserved after 5 days of storage at 70% relative humidity. It is anticipated that our research opens a new scope for high-performance extreme environment-tolerant adhesives or wearable devices.

Keywords: conductive; fast self-healing; repeatable adhesiveness; ultimate antifreezing; water-retaining.