Xylose- and Nucleoside-Based Polymers via Thiol–ene Polymerization toward Sugar-Derived Solid Polymer Electrolytes

A series of copolymers
have been prepared via thiol–ene
polymerization of bioderived α,ω-unsaturated diene monomers
with dithiols toward application as solid polymer electrolytes (SPEs)
for Li+-ion conduction. Amorphous polyesters and polyethers
with low Tg’s (−31 to −11
°C) were first prepared from xylose-based monomers (with varying
lengths of fatty acid moiety) and 2,2′-(ethylenedioxy)diethanethiol
(EDT). Cross-linking by incorporation of a trifunctional monomer also
produced a series of SPEs with ionic conductivities up to 2.2 ×
10–5 S cm–1 at 60 °C and
electrochemical stability up to 5.08 V, a significant improvement
over previous xylose-derived materials. Furthermore, a series of copolymers
bearing nucleoside moieties were prepared to exploit the complementary
base-pairing interaction of nucleobases. Flexible, transparent, and
reprocessable SPE films were thus prepared with improved ionic conductivity
(up to 1.5 × 10–4 S cm–1 at
60 °C), hydrolytic degradability, and potential self-healing
capabilities.