One-pot synthesis of self-healable and recyclable ionogels based on polyamidoamine (PAMAM) dendrimers via Schiff base reaction

Abstract

Novel ionogels with covalent polymeric networks based on polyamidoamine (PAMAM) dendrimers have been synthesized by the in situ crosslinking of amines via Schiff base reaction in the ionic liquid 1-ethyl-3-methylimidazolium acetate ([EMIM][OAc]). The obtained ionogels have excellent self-healing ability and recyclability. Rheological measurements revealed that the plateau modulus in storage modulus increases with increasing dendrimer content, and increasing generation of dendrimers results in the decrease of the plateau modulus due to geometrical reasons. The ionogels are very stable, and the reversible covalent networks are not destroyed at temperatures up to 160 °C, as indicated by dynamic temperature sweep measurements. Remarkably, the ionogels exhibit high ionic conductivity, and room-temperature ionic conductivity can reach 10⁻² S cm⁻¹. These self-healable and recyclable ionogels with high conductivity, good mechanical properties, and easy processability are desirable for flexible electronic devices with superior lifespans.