Structure and inter-phase stability in solvent-free low-dimensional polymer electrolytes with high lithium...

Area of Science:

• Polymer Chemistry
• Materials Science
• Electrochemistry

Background:

• Amphiphilic polymers are essential for developing advanced materials.
• The synthesis of poly[2,5,8,11,14-pentaoxapentadecamethylene(5-alkyloxy-1,3-phenylene)] (CmO5) is key for electrolyte applications.
• Understanding synthesis impacts on polymer properties is critical for performance.

Purpose of the Study:

• To compare two Williamson synthesis procedures for CmO5 polymers.
• To evaluate the influence of synthesis method on polymer structure and properties.
• To investigate the performance of CmO5-based polymer electrolytes.

Main Methods:

• Two distinct Williamson ether synthesis methods (Method X and Method Y) were employed.
• Dehydration reactions were used to form CmO5-CmO1 copolymers.
• Two-phase polymer electrolyte systems incorporating CmO5, other copolymers, and LiBF4 were prepared.

Main Results:

• Method X produced polyether-esters, while Method Y yielded pure polyethers.
• Polymer electrolytes containing CmO5 synthesized via Method Y exhibited a tendency for phase separation.
• The addition of an interfacial stabilizer copolymer (III) significantly enhanced conductivity (>5 x 10(-4) S cm(-1)) and stability.

Conclusions:

• The choice of synthesis method critically affects the resulting polymer structure and electrolyte phase behavior.
• Pure polyethers (from Method Y) are prone to phase separation in polymer electrolytes.
• Interfacial stabilization is vital for achieving high and stable ionic conductivity in these polymer systems.