<i>In situ</i> formation of ultrahigh molecular weight polymers in highly concentrated electrolytes and their physicochemical properties

We developed a facile one-pot method for fabricating physical gels consisting of ultrahigh molecular weight (UHMW) polymers and highly concentrated lithium salt electrolytes. We previously reported physical gels formed from the entanglement of UHMW polymers by radical polymerisation in aprotic ionic liquids. In this study, we found that the molecular weight of methacrylate polymers formed by radical polymerisation increased with the concentration of lithium salts in the organic solvents. Consequently, the synthesis of UHMW polymers with a high monomer conversion was achieved at very low initiator concentrations, leading to the formation of physical gels in highly concentrated electrolytes by the chain entanglement of UHMW polymers. The viscoelastic and mechanical properties of the UHMW gel electrolytes and their self-healing properties were investigated in detail.