Effects of a Mechanically Interlocked Structure on Ionic Conductivity in Polyrotaxane-Based Polymer Electrolytes

Polyrotaxane (PR) is a mechanically interlocked polymer (MIP) utilized as an electrolyte because of its distinctive property of dynamic molecular mobility. While numerous studies have concentrated on modifying external properties to decrease high crystallinity, few have explored the control of intrinsic properties. This study examines the crystalline properties and molecular mobility of PR-based electrolytes, along with their effects on ionic conductivity, by manipulating intrinsic properties. By systematically varying the inclusion ratio, we demonstrate that lower inclusion ratios lead to reduced crystallinity, enhancing molecular mobility. Consequently, 100PRE exhibits decreased crystallinity due to lower aggregation probabilities of α-cyclodextrins (α-CDs), longer <i>T</i>₂ relaxation times (0.215 s), and higher ionic conductivity (3.4 × 10^-3 S cm^-1 at 25 °C).