Incorporating allylated lignin-derivatives in thiol-ene gel-polymer electrolytes

Growing environmental and economic concerns as well as the uncertainty that accompanies finite petrochemical resources contributes to the increase in research and development of bio-based, renewable polymers. Concurrently, industrial and consumer demand for smaller, safer, and more flexible technologies motivates a global research effort to improve electrolytic polymer separators in lithium-ion batteries. To incorporate the aromatic structural advantages of lignin, a highly abundant and renewable resource, into gel-polymer electrolytes, lignin-derived molecules, vanillyl alcohol and gastrodigenin are functionalized and UV-polymerized with multifunctional thiol monomers. The resulting thin, flexible, polymer films possess glass transition temperatures ranging from -42.1 degrees C to 03 degrees C and storage moduli at 25 degrees C ranging from 1.90 MPa to 10.08 MPa. The crosslinked polymer films swollen with electrolyte solution impart conductivities in the range of 7.04 x 10(-7) to 102.73 x 10(-7) S cm(-1). Thiol molecular weight has the most impact on the thermo-mechanical properties of the resulting films while polymer crosslink density has the largest effect on conductivity. The conducting abilities of the bio-based gel-polymer electrolytes in this study prove the viability of lignin-derived feedstock for use in lithium-ion battery applications and reveal structurally and thermally desirable traits for future work (C) 2018 Elsevier B.V. All rights reserved.