Highly Stretchable, Elastic, Healable, and Ultra-Durable Polyvinyl Alcohol-Based Ionic Conductors Capable of Safe Disposal

Highly durable and stretchable ionic conductors are indispensable components of flexible electronics. However, fabricating such ionic conductors that are also non-toxic and biodegradable remains a challenge. In this study, highly stretchable, elastic, healable, and ultra-durable ionic conductors capable of non-hazardous disposal are conveniently fabricated by complexation of vanillin-grafted polyvinyl alcohol (VPVA) and ionic liquids (ILs) (denoted as VPVA-IL). No leakage of the loaded ILs occurs after repeatedly heating and pressing the ionic conductors. The VPVA-IL ionic conductor has an ionic conductivity of similar to 0.67 S m(-1), a tensile strength of similar to 2.01 MPa, and a strain at break of similar to 1231%. Meanwhile, the VPVA-IL ionic conductor shows a highly reproducible electrical response during 1100 uninterrupted extension-release cycles at a strain of 400%, demonstrating its excellent fatigue resistance and durability. Because of the reversibility of hydrogen bonds, the fractured ionic conductors can be easily healed at similar to 70 degrees C, restoring their original conductivity, stretchability, elasticity, and durability. Highly pure ILs can be easily separated from the VPVA-IL ionic conductors for reconstruction into new ionic conductors. The VPVA matrices, which are capable of completely degrading into non-toxic substances in soil, can be safely discarded without polluting the environment. [GRAPHICS]