Aluminosilicate/Poly(ethylene glycol) Copolymers: A New Class of Polyelectrolytes

摘要

Solvent-free polymer electrolytes are currently under intense scrutiny for use inhigh-energy density batteries and other electrochemical devices. In the most common polymer electrolytes, i.e., polymer-salt complexes, high anion transport numbers and low conductivity result in cell polarization and low power density. In addition, the mobility of both ions complicates the investigation of transport mechanisms. For these reasons, our group and others have investigated polyelectrolytes such as modified poly(phosphazene) with covalently bound anions and poly(tetraalkoxy aluminate). These polyelectrolytes ensure unity transport number for the cation. However, results from these investigations and others indicate that ion pairing limits the performance of these materials. To address this issue, our group has explored the use of sequestering agents (cryptands) and the use of very weakly basic anions attached to the polymer to reduce contact ion pairing. Aluminosilicates are attractive as low-basicity anions that can be incorporated into a polymer by siloxy linkages. In the present research, we prepared several alkoxy aluminosilicate polyelectrolytes to examine the effects of anion basicity on conductivity and explored the influence of added cryptand. jg.