Development of hydroxypropylated polyrotaxane networks with macromolecular PEG crosslinkers: Strategies for enhanced ionic conductivity

This work explores the design and optimization of polyrotaxane-based solid polymer electrolytes (SPEs) by adjusting crosslinker, composition, and polyrotaxane coverage ratio. By incorporating poly (ethylene glycol) (PEG) crosslinkers and refining their molecular weight and loading, we developed SPEs exhibiting high ionic conductivity (7.05 × 10⁻⁵ S/cm at 30 °C), excellent flexibility (elongation at break over 270 %) and thermal resistance above 150 °C. Investigations into polyrotaxane with reduced coverage ratios revealed limitations in mechanical properties and ionic conductivity, emphasizing the importance of PEG crosslinker and the need of a robust cross-linked network. This study underscores the potential of polyrotaxane cross-linked networks for advanced SPE applications and provides insights for future design strategies in the field.